TY  - CONF
AU  - Novović, Katarina
AU  - Jovčić, Branko
PY  - 2024
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2385
AB  - Acinetobacter baumannii is considered one of
the greatest threats to public health on a global
scale. This Gram-negative pathogen causes
severe infections, mostly of nosocomial origin,
with a high mortality rate. In recent years, the
rapid increase in the emergence and spread of
antibiotic resistance in A. baumannii has significantly
limited the effective therapeutic options
against infections caused by this bacterium.
The last-line antibiotics used in the treatment
of multidrug-resistant (MDR) A. baumannii
are carbapenems, tigecycline and polymyxins.
However, resistance to these antibiotics is
steadily increasing, especially to carbapenems,
leading to an extensively drug-resistant (XDR)
and even pandrug-resistant (PDR) phenotype
of A. baumannii. In 2021, the European Centre
for Disease Prevention and Control (ECDC) reported
that resistance of Acinetobacter spp. to
carbapenems reached 50% or more, mostly in
Southern and Eastern European countries. Although
the Western Balkans is a part of this region,
detailed studies on the epidemiology and
antibiotic resistance of A. baumannii are mainly
limited to Serbia and Croatia. In most cases, carbapenem
resistance in A. baumannii is due to
the production of carbapenemases, in particular
b-lactamases belonging to the class D known
as oxacillinases. The studies from the Western
Balkan countries revealed that besides the intrinsic
blaOXA-51-like gene, the most prevalent
acquired oxacillinase gene was the blaOXA-
24-like followed by the blaOXA-23-like, while
the blaOXA-58-like and metallo- b-lactamase
blaNDM-1 genes were less common. Although
significantly lower compared to carbapenem-resistant,
the number of A. baumannii isolates resistant
to tigecycline and colistin is on a continual
rise in the Western Balkans. As worldwide,
the main mechanism conferring tigecycline resistance
to A. baumannii from the Western Balkans
was overexpression of efflux pumps. Also,
the majority of reported alternations leading to
colistin resistance in A. baumannii were found in
the pmrCAB operon, which is responsible for the
modification of the colistin target, LPS.
PB  - Serbian Society for Microbiology
C3  - XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health
T1  - ACINETOBACTER BAUMANNII RESISTANT TO LAST-LINE ANTIBIOTICS: AN EMERGING THREAT IN THE WESTERN BALKANS
EP  - 174
SP  - 174
UR  - https://hdl.handle.net/21.15107/rcub_imagine_2385
ER  - 

@conference{
author = "Novović, Katarina and Jovčić, Branko",
year = "2024",
abstract = "Acinetobacter baumannii is considered one of
the greatest threats to public health on a global
scale. This Gram-negative pathogen causes
severe infections, mostly of nosocomial origin,
with a high mortality rate. In recent years, the
rapid increase in the emergence and spread of
antibiotic resistance in A. baumannii has significantly
limited the effective therapeutic options
against infections caused by this bacterium.
The last-line antibiotics used in the treatment
of multidrug-resistant (MDR) A. baumannii
are carbapenems, tigecycline and polymyxins.
However, resistance to these antibiotics is
steadily increasing, especially to carbapenems,
leading to an extensively drug-resistant (XDR)
and even pandrug-resistant (PDR) phenotype
of A. baumannii. In 2021, the European Centre
for Disease Prevention and Control (ECDC) reported
that resistance of Acinetobacter spp. to
carbapenems reached 50% or more, mostly in
Southern and Eastern European countries. Although
the Western Balkans is a part of this region,
detailed studies on the epidemiology and
antibiotic resistance of A. baumannii are mainly
limited to Serbia and Croatia. In most cases, carbapenem
resistance in A. baumannii is due to
the production of carbapenemases, in particular
b-lactamases belonging to the class D known
as oxacillinases. The studies from the Western
Balkan countries revealed that besides the intrinsic
blaOXA-51-like gene, the most prevalent
acquired oxacillinase gene was the blaOXA-
24-like followed by the blaOXA-23-like, while
the blaOXA-58-like and metallo- b-lactamase
blaNDM-1 genes were less common. Although
significantly lower compared to carbapenem-resistant,
the number of A. baumannii isolates resistant
to tigecycline and colistin is on a continual
rise in the Western Balkans. As worldwide,
the main mechanism conferring tigecycline resistance
to A. baumannii from the Western Balkans
was overexpression of efflux pumps. Also,
the majority of reported alternations leading to
colistin resistance in A. baumannii were found in
the pmrCAB operon, which is responsible for the
modification of the colistin target, LPS.",
publisher = "Serbian Society for Microbiology",
journal = "XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health",
title = "ACINETOBACTER BAUMANNII RESISTANT TO LAST-LINE ANTIBIOTICS: AN EMERGING THREAT IN THE WESTERN BALKANS",
pages = "174-174",
url = "https://hdl.handle.net/21.15107/rcub_imagine_2385"
}

Novović, K.,& Jovčić, B.. (2024). ACINETOBACTER BAUMANNII RESISTANT TO LAST-LINE ANTIBIOTICS: AN EMERGING THREAT IN THE WESTERN BALKANS. in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health
Serbian Society for Microbiology., 174-174.
https://hdl.handle.net/21.15107/rcub_imagine_2385

Novović K, Jovčić B. ACINETOBACTER BAUMANNII RESISTANT TO LAST-LINE ANTIBIOTICS: AN EMERGING THREAT IN THE WESTERN BALKANS. in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health. 2024;:174-174.
https://hdl.handle.net/21.15107/rcub_imagine_2385 .

Novović, Katarina, Jovčić, Branko, "ACINETOBACTER BAUMANNII RESISTANT TO LAST-LINE ANTIBIOTICS: AN EMERGING THREAT IN THE WESTERN BALKANS" in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health (2024):174-174,
https://hdl.handle.net/21.15107/rcub_imagine_2385 .

TY  - CONF
AU  - Ćurčić, Jovana
AU  - Malešević, Milka
AU  - Dinić, Miroslav
AU  - Novović, Katarina
AU  - Vasiljević, Zorica
AU  - Stanisavljević, Nemanja
AU  - Jovčić, Branko
PY  - 2024
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2380
AB  - Pseudomonas aeruginosa is a Gram-negative
pathogen responsible for frequent hospital-acquired
infections of the bloodstream, the respiratory
tract, and the urinary tract. Quorum
quenching enzymes are recognized as an alternative
antivirulence approach targeting pathogenic
bacteria. The efficacy of YtnP lactonase in
reducing the virulence of P. aeruginosa MMA83
in vivo using Caenorhabditis elegans as a model
system was investigated. The recombinant YtnP
lactonase exhibits no cytotoxicity, demonstrated
by its lack of harmful effects on both the
immortalized human HaCaT cell line and two
strains of C. elegans (AU37 and N2 wild-type). In
a toxin-mediated killing liquid assay, the survival
rates of C. elegans AU37 mutant and N2 wildtype
strains infected with the clinical isolate P.
aeruginosa MMA83 significantly increased when
pre-treated with YtnP lactonase, compared to
untreated controls. Considering that virulence
factors expression is regulated by quorum sensing
(QS) signaling it is hypothesized that YtnP
lactonase prolongs the life span of C. elegans
by downregulating the QS and expression of
virulence factors of MMA83. The protective effects
of YtnP lactonase against MMA83-induced
pathogenicity in C. elegans, coupled with its absence
of cytotoxicity, position YtnP lactonase as
a promising prophylactic agent with antivirulence
properties.
PB  - Serbian Society for Microbiology
C3  - XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health
T1  - YTNP LACTONASE IMPROVES THE ABILITY OF CAENORHABDITIS ELEGANS TO SURVIVE PSEUDOMONAS AERUGINOSA MMA83 INFECTION
EP  - 143
SP  - 143
UR  - https://hdl.handle.net/21.15107/rcub_imagine_2380
ER  - 

@conference{
author = "Ćurčić, Jovana and Malešević, Milka and Dinić, Miroslav and Novović, Katarina and Vasiljević, Zorica and Stanisavljević, Nemanja and Jovčić, Branko",
year = "2024",
abstract = "Pseudomonas aeruginosa is a Gram-negative
pathogen responsible for frequent hospital-acquired
infections of the bloodstream, the respiratory
tract, and the urinary tract. Quorum
quenching enzymes are recognized as an alternative
antivirulence approach targeting pathogenic
bacteria. The efficacy of YtnP lactonase in
reducing the virulence of P. aeruginosa MMA83
in vivo using Caenorhabditis elegans as a model
system was investigated. The recombinant YtnP
lactonase exhibits no cytotoxicity, demonstrated
by its lack of harmful effects on both the
immortalized human HaCaT cell line and two
strains of C. elegans (AU37 and N2 wild-type). In
a toxin-mediated killing liquid assay, the survival
rates of C. elegans AU37 mutant and N2 wildtype
strains infected with the clinical isolate P.
aeruginosa MMA83 significantly increased when
pre-treated with YtnP lactonase, compared to
untreated controls. Considering that virulence
factors expression is regulated by quorum sensing
(QS) signaling it is hypothesized that YtnP
lactonase prolongs the life span of C. elegans
by downregulating the QS and expression of
virulence factors of MMA83. The protective effects
of YtnP lactonase against MMA83-induced
pathogenicity in C. elegans, coupled with its absence
of cytotoxicity, position YtnP lactonase as
a promising prophylactic agent with antivirulence
properties.",
publisher = "Serbian Society for Microbiology",
journal = "XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health",
title = "YTNP LACTONASE IMPROVES THE ABILITY OF CAENORHABDITIS ELEGANS TO SURVIVE PSEUDOMONAS AERUGINOSA MMA83 INFECTION",
pages = "143-143",
url = "https://hdl.handle.net/21.15107/rcub_imagine_2380"
}

Ćurčić, J., Malešević, M., Dinić, M., Novović, K., Vasiljević, Z., Stanisavljević, N.,& Jovčić, B.. (2024). YTNP LACTONASE IMPROVES THE ABILITY OF CAENORHABDITIS ELEGANS TO SURVIVE PSEUDOMONAS AERUGINOSA MMA83 INFECTION. in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health
Serbian Society for Microbiology., 143-143.
https://hdl.handle.net/21.15107/rcub_imagine_2380

Ćurčić J, Malešević M, Dinić M, Novović K, Vasiljević Z, Stanisavljević N, Jovčić B. YTNP LACTONASE IMPROVES THE ABILITY OF CAENORHABDITIS ELEGANS TO SURVIVE PSEUDOMONAS AERUGINOSA MMA83 INFECTION. in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health. 2024;:143-143.
https://hdl.handle.net/21.15107/rcub_imagine_2380 .

Ćurčić, Jovana, Malešević, Milka, Dinić, Miroslav, Novović, Katarina, Vasiljević, Zorica, Stanisavljević, Nemanja, Jovčić, Branko, "YTNP LACTONASE IMPROVES THE ABILITY OF CAENORHABDITIS ELEGANS TO SURVIVE PSEUDOMONAS AERUGINOSA MMA83 INFECTION" in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health (2024):143-143,
https://hdl.handle.net/21.15107/rcub_imagine_2380 .

TY  - CONF
AU  - Šapić, Katarina
AU  - Novović, Katarina
AU  - Radovanović, Milica
AU  - Gajić, Ina
AU  - Vasiljević, Zorica
AU  - Malešević, Milka
AU  - Jovčić, Branko
PY  - 2024
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2386
AB  - The increasing prevalence of multidrug-resistant
(MDR) Acinetobacter baumannii limits effective
therapeutic options, and tigecycline has been
considered one of the last resort therapies for
MDR A. baumannii infections. Nevertheless, A.
baumannii isolates resistant to tigecycline are
becoming increasingly reported, mostly due to
overexpression of efflux pumps. The three major
RND efflux systems conferring tigecycline resistance
in A. baumannii are AdeABC, AdeFGH, and
AdeIJK, and their expression is regulated by the
two-component system AdeRS, the LysR-type
regulator AdeL, and the TetR-type regulator AdeN,
respectively. Following the above, we aimed
to determine the role of efflux pumps in tigecycline
resistance of thirty-seven A. baumannii isolates
collected from Western Balkan healthcare
settings (Serbia, Bosnia and Herzegovina and
Montenegro) in 2016 and 2022. The majority of
isolates belonged to the most prevalent international
clonal lineage IC2 (n = 32), four isolates are
members of IC1, while only one isolate is identified
as IC3. All tested isolates demonstrated a
significant decrease in tigecycline MIC in presence
of efflux pump inhibitor CCCP (≥16-fold reduction)
indicating that mechanism responsible
for tigecycline resistance is antibiotic efflux. The
comparison of target efflux pump regulatory
proteins, translated from nucleotide sequences,
to reference strains ATCC19606 and ATCC17978
revealed that most of the isolates have G186V
and N268H alternations in AdeS (n = 32), while
most common changes in AdeR were V120I and
A136V (n = 29) as described in previous studies.
Substitution Q262R was detected exclusively in
AdeL proteins of IC1 isolates, while no mutations
were observed within AdeN regulators. Expression
of the adeB, adeG, and adeJ genes in six selected
isolates was upregulated in four (1,4- to
3-fold), six (1,6- to 2,6-fold), and three isolates
(1,7- to 4-fold), respectively. This study confirmed
that overexpression of efflux pump encoding
genes enables tigecycline resistance in clinical
A. baumannii isolates.
PB  - Serbian Society for Microbiology
C3  - XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health
T1  - THE ROLE OF EFFLUX PUMPS IN TIGECYCLINE RESISTANCE OF ACINETOBACTER BAUMANNII ISOLATES FROM WESTERN BALKAN HOSPITALS
EP  - 187
SP  - 187
UR  - https://hdl.handle.net/21.15107/rcub_imagine_2386
ER  - 

@conference{
author = "Šapić, Katarina and Novović, Katarina and Radovanović, Milica and Gajić, Ina and Vasiljević, Zorica and Malešević, Milka and Jovčić, Branko",
year = "2024",
abstract = "The increasing prevalence of multidrug-resistant
(MDR) Acinetobacter baumannii limits effective
therapeutic options, and tigecycline has been
considered one of the last resort therapies for
MDR A. baumannii infections. Nevertheless, A.
baumannii isolates resistant to tigecycline are
becoming increasingly reported, mostly due to
overexpression of efflux pumps. The three major
RND efflux systems conferring tigecycline resistance
in A. baumannii are AdeABC, AdeFGH, and
AdeIJK, and their expression is regulated by the
two-component system AdeRS, the LysR-type
regulator AdeL, and the TetR-type regulator AdeN,
respectively. Following the above, we aimed
to determine the role of efflux pumps in tigecycline
resistance of thirty-seven A. baumannii isolates
collected from Western Balkan healthcare
settings (Serbia, Bosnia and Herzegovina and
Montenegro) in 2016 and 2022. The majority of
isolates belonged to the most prevalent international
clonal lineage IC2 (n = 32), four isolates are
members of IC1, while only one isolate is identified
as IC3. All tested isolates demonstrated a
significant decrease in tigecycline MIC in presence
of efflux pump inhibitor CCCP (≥16-fold reduction)
indicating that mechanism responsible
for tigecycline resistance is antibiotic efflux. The
comparison of target efflux pump regulatory
proteins, translated from nucleotide sequences,
to reference strains ATCC19606 and ATCC17978
revealed that most of the isolates have G186V
and N268H alternations in AdeS (n = 32), while
most common changes in AdeR were V120I and
A136V (n = 29) as described in previous studies.
Substitution Q262R was detected exclusively in
AdeL proteins of IC1 isolates, while no mutations
were observed within AdeN regulators. Expression
of the adeB, adeG, and adeJ genes in six selected
isolates was upregulated in four (1,4- to
3-fold), six (1,6- to 2,6-fold), and three isolates
(1,7- to 4-fold), respectively. This study confirmed
that overexpression of efflux pump encoding
genes enables tigecycline resistance in clinical
A. baumannii isolates.",
publisher = "Serbian Society for Microbiology",
journal = "XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health",
title = "THE ROLE OF EFFLUX PUMPS IN TIGECYCLINE RESISTANCE OF ACINETOBACTER BAUMANNII ISOLATES FROM WESTERN BALKAN HOSPITALS",
pages = "187-187",
url = "https://hdl.handle.net/21.15107/rcub_imagine_2386"
}

Šapić, K., Novović, K., Radovanović, M., Gajić, I., Vasiljević, Z., Malešević, M.,& Jovčić, B.. (2024). THE ROLE OF EFFLUX PUMPS IN TIGECYCLINE RESISTANCE OF ACINETOBACTER BAUMANNII ISOLATES FROM WESTERN BALKAN HOSPITALS. in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health
Serbian Society for Microbiology., 187-187.
https://hdl.handle.net/21.15107/rcub_imagine_2386

Šapić K, Novović K, Radovanović M, Gajić I, Vasiljević Z, Malešević M, Jovčić B. THE ROLE OF EFFLUX PUMPS IN TIGECYCLINE RESISTANCE OF ACINETOBACTER BAUMANNII ISOLATES FROM WESTERN BALKAN HOSPITALS. in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health. 2024;:187-187.
https://hdl.handle.net/21.15107/rcub_imagine_2386 .

Šapić, Katarina, Novović, Katarina, Radovanović, Milica, Gajić, Ina, Vasiljević, Zorica, Malešević, Milka, Jovčić, Branko, "THE ROLE OF EFFLUX PUMPS IN TIGECYCLINE RESISTANCE OF ACINETOBACTER BAUMANNII ISOLATES FROM WESTERN BALKAN HOSPITALS" in XIII Congress of microbiologists of Serbia: From biotechnology to human and planetary health (2024):187-187,
https://hdl.handle.net/21.15107/rcub_imagine_2386 .

TY  - JOUR
AU  - Ćurčić, Jovana
AU  - Dinić, Miroslav
AU  - Novović, Katarina
AU  - Vasiljević, Zorica
AU  - Kojić, Milan
AU  - Jovčić, Branko
AU  - Malešević, Milka
PY  - 2024
UR  - https://www.sciencedirect.com/science/article/pii/S0141813024012248
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2326
AB  - Infections caused by multidrug-resistant pathogens are one of the biggest challenges facing the healthcare system today. Quorum quenching (QQ) enzymes have the potential to be used as innovative enzyme-based antivirulence therapeutics to combat infections caused by multidrug-resistant pathogens. The main objective of this research was to describe the novel YtnP lactonase derived from the clinical isolate Stenotrophomonas maltophilia and to investigate its antivirulence potential against multidrug-resistant Pseudomonas aeruginosa MMA83. YtnP lactonase, the QQ enzyme, belongs to the family of metallo-β-lactamases. The recombinant enzyme has several advantageous biotechnological properties, such as high thermostability, activity in a wide pH range, and no cytotoxic effect. High-performance liquid chromatography analysis revealed the activity of recombinant YtnP lactonase toward a wide range of N-acyl-homoserine lactones (AHLs), quorum sensing signaling molecules, with a higher preference for long-chain AHLs. Recombinant YtnP lactonase was shown to inhibit P. aeruginosa MMA83 biofilm formation, induce biofilm decomposition, and reduce extracellular virulence factors production. Moreover, the lifespan of MMA83-infected Caenorhabditis elegans was prolonged with YtnP lactonase treatment. YtnP lactonase showed synergistic inhibitory activity in combination with gentamicin and acted additively with meropenem against MMA83. The described properties make YtnP lactonase a promising therapeutic candidate for the development of next-generation antivirulence agents.
PB  - Elsevier
T2  - International Journal of Biological Macromolecules
T2  - International Journal of Biological MacromoleculesInternational Journal of Biological Macromolecules
T1  - A novel thermostable YtnP lactonase from Stenotrophomonas maltophilia inhibits Pseudomonas aeruginosa virulence in vitro and in vivo
SP  - 130421
DO  - 10.1016/j.ijbiomac.2024.130421
ER  - 

@article{
author = "Ćurčić, Jovana and Dinić, Miroslav and Novović, Katarina and Vasiljević, Zorica and Kojić, Milan and Jovčić, Branko and Malešević, Milka",
year = "2024",
abstract = "Infections caused by multidrug-resistant pathogens are one of the biggest challenges facing the healthcare system today. Quorum quenching (QQ) enzymes have the potential to be used as innovative enzyme-based antivirulence therapeutics to combat infections caused by multidrug-resistant pathogens. The main objective of this research was to describe the novel YtnP lactonase derived from the clinical isolate Stenotrophomonas maltophilia and to investigate its antivirulence potential against multidrug-resistant Pseudomonas aeruginosa MMA83. YtnP lactonase, the QQ enzyme, belongs to the family of metallo-β-lactamases. The recombinant enzyme has several advantageous biotechnological properties, such as high thermostability, activity in a wide pH range, and no cytotoxic effect. High-performance liquid chromatography analysis revealed the activity of recombinant YtnP lactonase toward a wide range of N-acyl-homoserine lactones (AHLs), quorum sensing signaling molecules, with a higher preference for long-chain AHLs. Recombinant YtnP lactonase was shown to inhibit P. aeruginosa MMA83 biofilm formation, induce biofilm decomposition, and reduce extracellular virulence factors production. Moreover, the lifespan of MMA83-infected Caenorhabditis elegans was prolonged with YtnP lactonase treatment. YtnP lactonase showed synergistic inhibitory activity in combination with gentamicin and acted additively with meropenem against MMA83. The described properties make YtnP lactonase a promising therapeutic candidate for the development of next-generation antivirulence agents.",
publisher = "Elsevier",
journal = "International Journal of Biological Macromolecules, International Journal of Biological MacromoleculesInternational Journal of Biological Macromolecules",
title = "A novel thermostable YtnP lactonase from Stenotrophomonas maltophilia inhibits Pseudomonas aeruginosa virulence in vitro and in vivo",
pages = "130421",
doi = "10.1016/j.ijbiomac.2024.130421"
}

Ćurčić, J., Dinić, M., Novović, K., Vasiljević, Z., Kojić, M., Jovčić, B.,& Malešević, M.. (2024). A novel thermostable YtnP lactonase from Stenotrophomonas maltophilia inhibits Pseudomonas aeruginosa virulence in vitro and in vivo. in International Journal of Biological Macromolecules
Elsevier., 130421.
https://doi.org/10.1016/j.ijbiomac.2024.130421

Ćurčić J, Dinić M, Novović K, Vasiljević Z, Kojić M, Jovčić B, Malešević M. A novel thermostable YtnP lactonase from Stenotrophomonas maltophilia inhibits Pseudomonas aeruginosa virulence in vitro and in vivo. in International Journal of Biological Macromolecules. 2024;:130421.
doi:10.1016/j.ijbiomac.2024.130421 .

Ćurčić, Jovana, Dinić, Miroslav, Novović, Katarina, Vasiljević, Zorica, Kojić, Milan, Jovčić, Branko, Malešević, Milka, "A novel thermostable YtnP lactonase from Stenotrophomonas maltophilia inhibits Pseudomonas aeruginosa virulence in vitro and in vivo" in International Journal of Biological Macromolecules (2024):130421,
https://doi.org/10.1016/j.ijbiomac.2024.130421 . .

TY  - CONF
AU  - Novović, Katarina
AU  - Radovanović, Milica
AU  - Milić, Vukašin
AU  - Gajić, Ina
AU  - Vasiljević, Zorica
AU  - Jovčić, Branko
PY  - 2023
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2134
AB  - Introduction: Multidrug-resistant (MDR) Acinetobacter baumannii has been recognized as one of the
most serious healthcare challenges worldwide. Although tigecycline represents one of the last resort
therapies for MDR A. baumannii, resistance to this antibiotic has been reported and mostly is mediated
by AdeABC efflux pump. The aim of our study was to investigate the molecular mechanism responsible
for tigecycline resistance of thirty-seven A. baumannii isolates from Balkan medical settings (Serbia,
Bosnia and Herzegovina and Montenegro) gathered in 2016 and 2022.
Methods: Minimal inhibitory concentration (MIC) values for tigecycline were determined using microdilution method according to EUCAST guidelines. Inhibition of the efflux of tigecycline wastested by
the same method using a combination of antibiotic and efflux pump inhibitor (CCCP). Amino acid alternations within AdeS and AdeR proteins were detected by comparing to sequences of referent isolates
ATCC19606 and ATCC17978. Expression of the adeB gene ofselected isolates was monitored by RT-qPCR.
Results: All tested isolates were resistant to tigecycline and showed significant decrease in tigecycline
MIC values in presence of CCCP (≥16-fold reduction) indicating that antibiotic efflux is responsible for
tigecycline resistance. The analysis of two-component system AdeRS, regulatory system of RND efflux
pump AdeABC, revealed that most of the isolates have G186V and N268H alternations in AdeS (n=32),
while most common changes in AdeR were V120I and A136V (n=29). In addition, RT-qPCR showed that
selected isolates upregulate expression of the adeB gene (from 1,13- to 3-fold).
Conclusion: This study revealed that AdeABC overexpression is the main mechanism of tigecycline resistance in A. baumannii isolated in Balkan hospitals.
PB  - Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade
C3  - CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia
T1  - AdeABC efflux pump-mediated resistance to tigecycline in Acinetobacter baumannii isolates from Balkan hospitals
EP  - 154
SP  - 154
UR  - https://hdl.handle.net/21.15107/rcub_imagine_2134
ER  - 

@conference{
author = "Novović, Katarina and Radovanović, Milica and Milić, Vukašin and Gajić, Ina and Vasiljević, Zorica and Jovčić, Branko",
year = "2023",
abstract = "Introduction: Multidrug-resistant (MDR) Acinetobacter baumannii has been recognized as one of the
most serious healthcare challenges worldwide. Although tigecycline represents one of the last resort
therapies for MDR A. baumannii, resistance to this antibiotic has been reported and mostly is mediated
by AdeABC efflux pump. The aim of our study was to investigate the molecular mechanism responsible
for tigecycline resistance of thirty-seven A. baumannii isolates from Balkan medical settings (Serbia,
Bosnia and Herzegovina and Montenegro) gathered in 2016 and 2022.
Methods: Minimal inhibitory concentration (MIC) values for tigecycline were determined using microdilution method according to EUCAST guidelines. Inhibition of the efflux of tigecycline wastested by
the same method using a combination of antibiotic and efflux pump inhibitor (CCCP). Amino acid alternations within AdeS and AdeR proteins were detected by comparing to sequences of referent isolates
ATCC19606 and ATCC17978. Expression of the adeB gene ofselected isolates was monitored by RT-qPCR.
Results: All tested isolates were resistant to tigecycline and showed significant decrease in tigecycline
MIC values in presence of CCCP (≥16-fold reduction) indicating that antibiotic efflux is responsible for
tigecycline resistance. The analysis of two-component system AdeRS, regulatory system of RND efflux
pump AdeABC, revealed that most of the isolates have G186V and N268H alternations in AdeS (n=32),
while most common changes in AdeR were V120I and A136V (n=29). In addition, RT-qPCR showed that
selected isolates upregulate expression of the adeB gene (from 1,13- to 3-fold).
Conclusion: This study revealed that AdeABC overexpression is the main mechanism of tigecycline resistance in A. baumannii isolated in Balkan hospitals.",
publisher = "Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade",
journal = "CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia",
title = "AdeABC efflux pump-mediated resistance to tigecycline in Acinetobacter baumannii isolates from Balkan hospitals",
pages = "154-154",
url = "https://hdl.handle.net/21.15107/rcub_imagine_2134"
}

Novović, K., Radovanović, M., Milić, V., Gajić, I., Vasiljević, Z.,& Jovčić, B.. (2023). AdeABC efflux pump-mediated resistance to tigecycline in Acinetobacter baumannii isolates from Balkan hospitals. in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia
Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade., 154-154.
https://hdl.handle.net/21.15107/rcub_imagine_2134

Novović K, Radovanović M, Milić V, Gajić I, Vasiljević Z, Jovčić B. AdeABC efflux pump-mediated resistance to tigecycline in Acinetobacter baumannii isolates from Balkan hospitals. in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia. 2023;:154-154.
https://hdl.handle.net/21.15107/rcub_imagine_2134 .

Novović, Katarina, Radovanović, Milica, Milić, Vukašin, Gajić, Ina, Vasiljević, Zorica, Jovčić, Branko, "AdeABC efflux pump-mediated resistance to tigecycline in Acinetobacter baumannii isolates from Balkan hospitals" in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia (2023):154-154,
https://hdl.handle.net/21.15107/rcub_imagine_2134 .

TY  - JOUR
AU  - Novović, Katarina
AU  - Jovčić, Branko
PY  - 2023
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1786
AB  - : Acinetobacter baumannii is recognized as a clinically significant pathogen causing a wide
spectrum of nosocomial infections. Colistin was considered a last-resort antibiotic for the treatment of
infections caused by multidrug-resistant A. baumannii. Since the reintroduction of colistin, a number
of mechanisms of colistin resistance in A. baumannii have been reported, including complete loss of
LPS by inactivation of the biosynthetic pathway, modifications of target LPS driven by the addition
of phosphoethanolamine (PEtN) moieties to lipid A mediated by the chromosomal pmrCAB operon
and eptA gene-encoded enzymes or plasmid-encoded mcr genes and efflux of colistin from the cell.
In addition to resistance to colistin, widespread heteroresistance is another feature of A. baumannii
that leads to colistin treatment failure. This review aims to present a critical assessment of relevant
published (>50 experimental papers) up-to-date knowledge on the molecular mechanisms of colistin
resistance in A. baumannii with a detailed review of implicated mutations and the global distribution
of colistin-resistant strains.
PB  - MDPI
T2  - Antibiotics
T1  - Colistin resistance in acinetobacter baumannii: Molecular mechanisms and epidemiology
IS  - 3
SP  - 516
VL  - 12
DO  - 10.3390/antibiotics12030516
ER  - 

@article{
author = "Novović, Katarina and Jovčić, Branko",
year = "2023",
abstract = ": Acinetobacter baumannii is recognized as a clinically significant pathogen causing a wide
spectrum of nosocomial infections. Colistin was considered a last-resort antibiotic for the treatment of
infections caused by multidrug-resistant A. baumannii. Since the reintroduction of colistin, a number
of mechanisms of colistin resistance in A. baumannii have been reported, including complete loss of
LPS by inactivation of the biosynthetic pathway, modifications of target LPS driven by the addition
of phosphoethanolamine (PEtN) moieties to lipid A mediated by the chromosomal pmrCAB operon
and eptA gene-encoded enzymes or plasmid-encoded mcr genes and efflux of colistin from the cell.
In addition to resistance to colistin, widespread heteroresistance is another feature of A. baumannii
that leads to colistin treatment failure. This review aims to present a critical assessment of relevant
published (>50 experimental papers) up-to-date knowledge on the molecular mechanisms of colistin
resistance in A. baumannii with a detailed review of implicated mutations and the global distribution
of colistin-resistant strains.",
publisher = "MDPI",
journal = "Antibiotics",
title = "Colistin resistance in acinetobacter baumannii: Molecular mechanisms and epidemiology",
number = "3",
pages = "516",
volume = "12",
doi = "10.3390/antibiotics12030516"
}

Novović, K.,& Jovčić, B.. (2023). Colistin resistance in acinetobacter baumannii: Molecular mechanisms and epidemiology. in Antibiotics
MDPI., 12(3), 516.
https://doi.org/10.3390/antibiotics12030516

Novović K, Jovčić B. Colistin resistance in acinetobacter baumannii: Molecular mechanisms and epidemiology. in Antibiotics. 2023;12(3):516.
doi:10.3390/antibiotics12030516 .

Novović, Katarina, Jovčić, Branko, "Colistin resistance in acinetobacter baumannii: Molecular mechanisms and epidemiology" in Antibiotics, 12, no. 3 (2023):516,
https://doi.org/10.3390/antibiotics12030516 . .

TY  - DATA
AU  - Kabić, Jovana
AU  - Novović, Katarina
AU  - Kekić, Dušan
AU  - Trudić, Anika
AU  - Opavski, Nataša
AU  - Dimkić, Ivica
AU  - Jovčić, Branko
AU  - Gajić, Ina
PY  - 2023
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1785
T2  - Computational and Structural Biotechnology Journal
T2  - Computational and Structural Biotechnology JournalComputational and Structural Biotechnology Journal
T1  - Supplementary information for the article: Kabic, J., Novovic, K., Kekic, D., Trudic, A., Opavski, N., Dimkic, I., Jovcic, B., & Gajic, I. (2023). Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. Computational and Structural Biotechnology Journal, 21, 574–585. https://doi.org/10.1016/j.csbj.2022.12.045
UR  - https://hdl.handle.net/21.15107/rcub_imagine_1785
ER  - 

@misc{
author = "Kabić, Jovana and Novović, Katarina and Kekić, Dušan and Trudić, Anika and Opavski, Nataša and Dimkić, Ivica and Jovčić, Branko and Gajić, Ina",
year = "2023",
journal = "Computational and Structural Biotechnology Journal, Computational and Structural Biotechnology JournalComputational and Structural Biotechnology Journal",
title = "Supplementary information for the article: Kabic, J., Novovic, K., Kekic, D., Trudic, A., Opavski, N., Dimkic, I., Jovcic, B., & Gajic, I. (2023). Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. Computational and Structural Biotechnology Journal, 21, 574–585. https://doi.org/10.1016/j.csbj.2022.12.045",
url = "https://hdl.handle.net/21.15107/rcub_imagine_1785"
}

Kabić, J., Novović, K., Kekić, D., Trudić, A., Opavski, N., Dimkić, I., Jovčić, B.,& Gajić, I.. (2023). Supplementary information for the article: Kabic, J., Novovic, K., Kekic, D., Trudic, A., Opavski, N., Dimkic, I., Jovcic, B., & Gajic, I. (2023). Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. Computational and Structural Biotechnology Journal, 21, 574–585. https://doi.org/10.1016/j.csbj.2022.12.045. in Computational and Structural Biotechnology Journal.
https://hdl.handle.net/21.15107/rcub_imagine_1785

Kabić J, Novović K, Kekić D, Trudić A, Opavski N, Dimkić I, Jovčić B, Gajić I. Supplementary information for the article: Kabic, J., Novovic, K., Kekic, D., Trudic, A., Opavski, N., Dimkic, I., Jovcic, B., & Gajic, I. (2023). Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. Computational and Structural Biotechnology Journal, 21, 574–585. https://doi.org/10.1016/j.csbj.2022.12.045. in Computational and Structural Biotechnology Journal. 2023;.
https://hdl.handle.net/21.15107/rcub_imagine_1785 .

Kabić, Jovana, Novović, Katarina, Kekić, Dušan, Trudić, Anika, Opavski, Nataša, Dimkić, Ivica, Jovčić, Branko, Gajić, Ina, "Supplementary information for the article: Kabic, J., Novovic, K., Kekic, D., Trudic, A., Opavski, N., Dimkic, I., Jovcic, B., & Gajic, I. (2023). Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. Computational and Structural Biotechnology Journal, 21, 574–585. https://doi.org/10.1016/j.csbj.2022.12.045" in Computational and Structural Biotechnology Journal (2023),
https://hdl.handle.net/21.15107/rcub_imagine_1785 .

TY  - CONF
AU  - Carević, Tamara
AU  - Novović, Katarina
AU  - Ivanov, Marija
PY  - 2023
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2115
AB  - Introduction: Differentsugars are commonly used in the diet, but little is understood about the various
effects of human health that they can affect. Hence, the impact of sugars and their substitutes used in
diet on the development of virulence in Pseudomonas aeruginosa PAO1 was investigated. Sugars (fructose, demerara, coconut sugar, and cane sugar) and sugar substitutes (erythritol and stevia) were selected. The genes from three P. aeruginosa QS networks (las - lasI, lasR; rhl - rhlI, rhlR; PQS - pqsA, mvfR)
were used for RT-qPCR analysis in order to investigate whether the expression of these genes changes.
In this work, the focusis on the expression of genesinvolved in QS and the ability to form biofilms(a type
of structured community of microorganisms that is attached to the surface and connected by an exopolysaccharide matrix), as well as determining minimal inhibitory concentration of antibiotics in presence of tested compounds.
Methods: Microdiltuion assay, Antibiofilm assay, RT- qPCR
Results: In the presence of tested sugars and theirsubstitutes, the minimum inhibitory concentration of
commercial antibiotics increased, as well as the percentages of biofilm formation (for instance, the percentage of biofilm formation is 171% in the presence of coconut sugar). Furthermore, exposure of P.
aeruginosa to tested compounds caused the greatest increase in expression of virulence associated with
the lasI and pvdF genes.
Conclusion: More awareness and research is needed to highlight the effectssugars can have on P. aeruginosa and to propose new strategies to reduce this negative aspect.
PB  - Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade
C3  - CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia
T1  - Sugars and their substitutes increase pathogenicity of Pseudomonas aeruginosa
EP  - 48
SP  - 48
UR  - https://hdl.handle.net/21.15107/rcub_imagine_2115
ER  - 

@conference{
author = "Carević, Tamara and Novović, Katarina and Ivanov, Marija",
year = "2023",
abstract = "Introduction: Differentsugars are commonly used in the diet, but little is understood about the various
effects of human health that they can affect. Hence, the impact of sugars and their substitutes used in
diet on the development of virulence in Pseudomonas aeruginosa PAO1 was investigated. Sugars (fructose, demerara, coconut sugar, and cane sugar) and sugar substitutes (erythritol and stevia) were selected. The genes from three P. aeruginosa QS networks (las - lasI, lasR; rhl - rhlI, rhlR; PQS - pqsA, mvfR)
were used for RT-qPCR analysis in order to investigate whether the expression of these genes changes.
In this work, the focusis on the expression of genesinvolved in QS and the ability to form biofilms(a type
of structured community of microorganisms that is attached to the surface and connected by an exopolysaccharide matrix), as well as determining minimal inhibitory concentration of antibiotics in presence of tested compounds.
Methods: Microdiltuion assay, Antibiofilm assay, RT- qPCR
Results: In the presence of tested sugars and theirsubstitutes, the minimum inhibitory concentration of
commercial antibiotics increased, as well as the percentages of biofilm formation (for instance, the percentage of biofilm formation is 171% in the presence of coconut sugar). Furthermore, exposure of P.
aeruginosa to tested compounds caused the greatest increase in expression of virulence associated with
the lasI and pvdF genes.
Conclusion: More awareness and research is needed to highlight the effectssugars can have on P. aeruginosa and to propose new strategies to reduce this negative aspect.",
publisher = "Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade",
journal = "CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia",
title = "Sugars and their substitutes increase pathogenicity of Pseudomonas aeruginosa",
pages = "48-48",
url = "https://hdl.handle.net/21.15107/rcub_imagine_2115"
}

Carević, T., Novović, K.,& Ivanov, M.. (2023). Sugars and their substitutes increase pathogenicity of Pseudomonas aeruginosa. in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia
Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade., 48-48.
https://hdl.handle.net/21.15107/rcub_imagine_2115

Carević T, Novović K, Ivanov M. Sugars and their substitutes increase pathogenicity of Pseudomonas aeruginosa. in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia. 2023;:48-48.
https://hdl.handle.net/21.15107/rcub_imagine_2115 .

Carević, Tamara, Novović, Katarina, Ivanov, Marija, "Sugars and their substitutes increase pathogenicity of Pseudomonas aeruginosa" in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia (2023):48-48,
https://hdl.handle.net/21.15107/rcub_imagine_2115 .

TY  - JOUR
AU  - Kabić, Jovana
AU  - Novović, Katarina
AU  - Kekić, Dušan
AU  - Trudić, Anika
AU  - Opavski, Nataša
AU  - Dimkić, Ivica
AU  - Jovčić, Branko
AU  - Gajić, Ina
PY  - 2023
UR  - https://www.sciencedirect.com/science/article/pii/S200103702200602X
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1784
AB  - This study aimed to investigate the prevalence and resistance mechanisms of colistin-resistant Acinetobacter baumannii (ColRAB) isolates in Serbia, assess their genetic relatedness to other circulating A. baumannii isolates in the neighbouring European countries, and analyse the global genomic epidemiology of ColRAB isolates. A total of 784 isolates of A. baumannii were recovered from hospitalised patients in Serbia between 2018 and 2021. The antimicrobial susceptibility testing was performed using disk diffusion and broth microdilution. All ColRAB isolates were subjected to DNA isolation and whole-genome sequencing (WGS). Overall, 3.94 % (n = 30) isolates were confirmed as ColRAB. Results of mutational and transcriptional analysis of genes associated with colistin resistance indicate the central role of the two-component regulating system, PmrAB, and increased expression of the pmrC gene in ColRAB. Most of the isolates (n = 29, 96.6 %) belonged to international clone II, with the most common sequence type being STPas2 (n = 23, 76.6 %). Based on the WGS analysis, ColRAB isolates belonging to the same ST isolated in various countries were grouped into the same clusters, indicating the global dissemination of several high-risk clonal lineages. Phylogenomic analysis of ColRAB isolates, together with all previously published A. baumannii genomes from South-Eastern European countries, showed that colistin resistance arose independently in several clonal lineages. Comparative genomic analysis revealed multiple genes with various roles (transcriptional regulation, transmembrane transport, outer membrane assembly, etc.), which might be associated with colistin resistance in A. baumannii. The obtained findings serve as the basis for further studies, contributing to a better understanding of colistin resistance mechanisms in A. baumannii.
T2  - Computational and Structural Biotechnology Journal
T2  - Computational and Structural Biotechnology JournalComputational and Structural Biotechnology Journal
T1  - Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii
EP  - 585
SP  - 574
VL  - 21
DO  - 10.1016/j.csbj.2022.12.045
DO  - 10.1016/j.csbj.2022.12.045
ER  - 

@article{
author = "Kabić, Jovana and Novović, Katarina and Kekić, Dušan and Trudić, Anika and Opavski, Nataša and Dimkić, Ivica and Jovčić, Branko and Gajić, Ina",
year = "2023",
abstract = "This study aimed to investigate the prevalence and resistance mechanisms of colistin-resistant Acinetobacter baumannii (ColRAB) isolates in Serbia, assess their genetic relatedness to other circulating A. baumannii isolates in the neighbouring European countries, and analyse the global genomic epidemiology of ColRAB isolates. A total of 784 isolates of A. baumannii were recovered from hospitalised patients in Serbia between 2018 and 2021. The antimicrobial susceptibility testing was performed using disk diffusion and broth microdilution. All ColRAB isolates were subjected to DNA isolation and whole-genome sequencing (WGS). Overall, 3.94 % (n = 30) isolates were confirmed as ColRAB. Results of mutational and transcriptional analysis of genes associated with colistin resistance indicate the central role of the two-component regulating system, PmrAB, and increased expression of the pmrC gene in ColRAB. Most of the isolates (n = 29, 96.6 %) belonged to international clone II, with the most common sequence type being STPas2 (n = 23, 76.6 %). Based on the WGS analysis, ColRAB isolates belonging to the same ST isolated in various countries were grouped into the same clusters, indicating the global dissemination of several high-risk clonal lineages. Phylogenomic analysis of ColRAB isolates, together with all previously published A. baumannii genomes from South-Eastern European countries, showed that colistin resistance arose independently in several clonal lineages. Comparative genomic analysis revealed multiple genes with various roles (transcriptional regulation, transmembrane transport, outer membrane assembly, etc.), which might be associated with colistin resistance in A. baumannii. The obtained findings serve as the basis for further studies, contributing to a better understanding of colistin resistance mechanisms in A. baumannii.",
journal = "Computational and Structural Biotechnology Journal, Computational and Structural Biotechnology JournalComputational and Structural Biotechnology Journal",
title = "Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii",
pages = "585-574",
volume = "21",
doi = "10.1016/j.csbj.2022.12.045, 10.1016/j.csbj.2022.12.045"
}

Kabić, J., Novović, K., Kekić, D., Trudić, A., Opavski, N., Dimkić, I., Jovčić, B.,& Gajić, I.. (2023). Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. in Computational and Structural Biotechnology Journal, 21, 574-585.
https://doi.org/10.1016/j.csbj.2022.12.045

Kabić J, Novović K, Kekić D, Trudić A, Opavski N, Dimkić I, Jovčić B, Gajić I. Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii. in Computational and Structural Biotechnology Journal. 2023;21:574-585.
doi:10.1016/j.csbj.2022.12.045 .

Kabić, Jovana, Novović, Katarina, Kekić, Dušan, Trudić, Anika, Opavski, Nataša, Dimkić, Ivica, Jovčić, Branko, Gajić, Ina, "Comparative genomics and molecular epidemiology of colistin-resistant Acinetobacter baumannii" in Computational and Structural Biotechnology Journal, 21 (2023):574-585,
https://doi.org/10.1016/j.csbj.2022.12.045 . .

TY  - DATA
AU  - Novović, Katarina
AU  - Kuzmanović Nedeljković, Snežana
AU  - Poledica, Mirjana
AU  - Nikolić, Gordana
AU  - Grujić, Bojana
AU  - Jovčić, Branko
AU  - Kojić, Milan
AU  - Filipić, Brankica
PY  - 2023
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1783
T2  - Frontiers in Microbiology
T2  - Frontiers in Microbiology
T1  - Supplementary information for the article: Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M., & Filipić, B. (2023). Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. Frontiers in Microbiology, 14. https://www.frontiersin.org/articles/10.3389/fmicb.2023.1094184
UR  - https://hdl.handle.net/21.15107/rcub_imagine_1783
ER  - 

@misc{
author = "Novović, Katarina and Kuzmanović Nedeljković, Snežana and Poledica, Mirjana and Nikolić, Gordana and Grujić, Bojana and Jovčić, Branko and Kojić, Milan and Filipić, Brankica",
year = "2023",
journal = "Frontiers in Microbiology, Frontiers in Microbiology",
title = "Supplementary information for the article: Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M., & Filipić, B. (2023). Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. Frontiers in Microbiology, 14. https://www.frontiersin.org/articles/10.3389/fmicb.2023.1094184",
url = "https://hdl.handle.net/21.15107/rcub_imagine_1783"
}

Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M.,& Filipić, B.. (2023). Supplementary information for the article: Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M., & Filipić, B. (2023). Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. Frontiers in Microbiology, 14. https://www.frontiersin.org/articles/10.3389/fmicb.2023.1094184. in Frontiers in Microbiology.
https://hdl.handle.net/21.15107/rcub_imagine_1783

Novović K, Kuzmanović Nedeljković S, Poledica M, Nikolić G, Grujić B, Jovčić B, Kojić M, Filipić B. Supplementary information for the article: Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M., & Filipić, B. (2023). Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. Frontiers in Microbiology, 14. https://www.frontiersin.org/articles/10.3389/fmicb.2023.1094184. in Frontiers in Microbiology. 2023;.
https://hdl.handle.net/21.15107/rcub_imagine_1783 .

Novović, Katarina, Kuzmanović Nedeljković, Snežana, Poledica, Mirjana, Nikolić, Gordana, Grujić, Bojana, Jovčić, Branko, Kojić, Milan, Filipić, Brankica, "Supplementary information for the article: Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M., & Filipić, B. (2023). Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. Frontiers in Microbiology, 14. https://www.frontiersin.org/articles/10.3389/fmicb.2023.1094184" in Frontiers in Microbiology (2023),
https://hdl.handle.net/21.15107/rcub_imagine_1783 .

TY  - CONF
AU  - Ćurčić, Jovana
AU  - Jakovljević, Stefan
AU  - Novović, Katarina
AU  - Vasiljević, Zorica
AU  - Kojić, Milan
AU  - Jovčić, Branko
AU  - Malešević, Milka
PY  - 2023
UR  - http://intor.torlakinstitut.com/handle/123456789/803
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/2124
AB  - Introduction: Quorum quenching (QQ) isthe enzymatic degradation of cell-to-cellsignaling molecules.In this study, the potential of the novel YtnP lactonase, the quorum quenching enzyme derived from S.maltophilia, to reduce P. aeruginosa quorum sensing and virulence factor gene expression was investigated.Methods: MMA83 culture (adjusted to 1.5x105 CFU/ml) was treated with recombinant YtnP lactonase(final concentration 50 μg/ml) at 37°C for 12 hours under aeration. RNA isolation of the treated and untreated MMA83 culture was performed using the RNeasy Mini Kit (Qiagen, Germany) according to theprotocol. Quantitative reverse transcription-polymerase chain reaction (RT-qPCR), was used to analyzethe effect ofYtnP lactonase on the relative mRNA levels of the LasI/LasR, RhiI/RhiR, and PQS signaling network genes of P. aeruginosa MMA83 and virulence factor genes. The rpsL was used as an endogenouscontrol to normalize obtained data following the 2-ΔΔCt method.Results: The QS genes belonging to three QS networks – LasI/LasR, RhiI/RhiR, and PQS of P. aeruginosaMMA83 treated with YtnP lactonase were significantly downregulated. The RT -qPCR results show thattreatment with YtnP-lactonase decreased the relative mRNA levels of genes involved in the productionof elastase (lasB approximately 2-fold), alginate (algK approximately 2.2-fold), pyocyanin (phzM approximately 3.5-fold), pyoverdin (pvdS approximately 2-fold), and rhamnolipid (rhlC approximately 4-fold).These results suggest that YtnP lactonase exerts an antivirulence effect at the transcription level.Conclusion: YtnP lactonase, a quorum quenching (QQ) enzyme, has the potential to be used as an innovative enzyme-based antivirulence therapeutic to combat infections caused by P. aeruginosa.
PB  - Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade
C3  - CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia
T1  - A novel YtnP lactonase reduces the expression of p. aeruginosa MMA83 quorum sensing andvirulence factors gene expression
EP  - 121
SP  - 121
UR  - https://hdl.handle.net/21.15107/rcub_imagine_2124
ER  - 

@conference{
author = "Ćurčić, Jovana and Jakovljević, Stefan and Novović, Katarina and Vasiljević, Zorica and Kojić, Milan and Jovčić, Branko and Malešević, Milka",
year = "2023",
abstract = "Introduction: Quorum quenching (QQ) isthe enzymatic degradation of cell-to-cellsignaling molecules.In this study, the potential of the novel YtnP lactonase, the quorum quenching enzyme derived from S.maltophilia, to reduce P. aeruginosa quorum sensing and virulence factor gene expression was investigated.Methods: MMA83 culture (adjusted to 1.5x105 CFU/ml) was treated with recombinant YtnP lactonase(final concentration 50 μg/ml) at 37°C for 12 hours under aeration. RNA isolation of the treated and untreated MMA83 culture was performed using the RNeasy Mini Kit (Qiagen, Germany) according to theprotocol. Quantitative reverse transcription-polymerase chain reaction (RT-qPCR), was used to analyzethe effect ofYtnP lactonase on the relative mRNA levels of the LasI/LasR, RhiI/RhiR, and PQS signaling network genes of P. aeruginosa MMA83 and virulence factor genes. The rpsL was used as an endogenouscontrol to normalize obtained data following the 2-ΔΔCt method.Results: The QS genes belonging to three QS networks – LasI/LasR, RhiI/RhiR, and PQS of P. aeruginosaMMA83 treated with YtnP lactonase were significantly downregulated. The RT -qPCR results show thattreatment with YtnP-lactonase decreased the relative mRNA levels of genes involved in the productionof elastase (lasB approximately 2-fold), alginate (algK approximately 2.2-fold), pyocyanin (phzM approximately 3.5-fold), pyoverdin (pvdS approximately 2-fold), and rhamnolipid (rhlC approximately 4-fold).These results suggest that YtnP lactonase exerts an antivirulence effect at the transcription level.Conclusion: YtnP lactonase, a quorum quenching (QQ) enzyme, has the potential to be used as an innovative enzyme-based antivirulence therapeutic to combat infections caused by P. aeruginosa.",
publisher = "Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade",
journal = "CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia",
title = "A novel YtnP lactonase reduces the expression of p. aeruginosa MMA83 quorum sensing andvirulence factors gene expression",
pages = "121-121",
url = "https://hdl.handle.net/21.15107/rcub_imagine_2124"
}

Ćurčić, J., Jakovljević, S., Novović, K., Vasiljević, Z., Kojić, M., Jovčić, B.,& Malešević, M.. (2023). A novel YtnP lactonase reduces the expression of p. aeruginosa MMA83 quorum sensing andvirulence factors gene expression. in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia
Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade., 121-121.
https://hdl.handle.net/21.15107/rcub_imagine_2124

Ćurčić J, Jakovljević S, Novović K, Vasiljević Z, Kojić M, Jovčić B, Malešević M. A novel YtnP lactonase reduces the expression of p. aeruginosa MMA83 quorum sensing andvirulence factors gene expression. in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia. 2023;:121-121.
https://hdl.handle.net/21.15107/rcub_imagine_2124 .

Ćurčić, Jovana, Jakovljević, Stefan, Novović, Katarina, Vasiljević, Zorica, Kojić, Milan, Jovčić, Branko, Malešević, Milka, "A novel YtnP lactonase reduces the expression of p. aeruginosa MMA83 quorum sensing andvirulence factors gene expression" in CoMBoS2 – the Second Congress of Molecular Biologists of Serbia, Abstract Book – Trends in Molecular Biology, Special issue 06-08 October 2023, Belgrade, Serbia (2023):121-121,
https://hdl.handle.net/21.15107/rcub_imagine_2124 .

TY  - JOUR
AU  - Novović, Katarina
AU  - Kuzmanović Nedeljković, Snežana
AU  - Poledica, Mirjana
AU  - Nikolić, Gordana
AU  - Grujić, Bojana
AU  - Jovčić, Branko
AU  - Kojić, Milan
AU  - Filipić, Brankica
PY  - 2023
UR  - https://www.frontiersin.org/articles/10.3389/fmicb.2023.1094184
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1782
AB  - Since the WHO declared the COVID-19 pandemic in March 2020, the disease has spread rapidly leading to overload of the health system and many of the patients infected with SARS-CoV-2 needed to be admitted to the intensive care unit (ICU). Around 10% of patients with the severe manifestation of COVID-19 need noninvasive or invasive mechanical ventilation, which represent a risk factor for Acinetobacter baumannii superinfection. The 64 A. baumannii isolates were recovered from COVID-19 patients admitted to ICU at General Hospital “Dr Laza K. Lazarević” Šabac, Serbia, during the period from December 2020 to February 2021. All patients required mechanical ventilation and mortality rate was 100%. The goal of this study was to evaluate antibiotic resistance profiles and virulence potential of A. baumannii isolates recovered from patients with severe form of COVID-19 who had a need for mechanical ventilation. All tested A. baumannii isolates (n = 64) were sensitive to colistin, while resistant to meropenem, imipenem, gentamicin, tobramycin, and levofloxacin according to the broth microdilution method and MDR phenotype was confirmed. In all tested isolates, representatives of international clone 2 (IC2) classified by multiplex PCR for clonal lineage identification, blaAmpC, blaOXA-51, and blaOXA-23 genes were present, as well as ISAba1 insertion sequence upstream of blaOXA-23. Clonal distribution of one dominant strain was found, but individual strains showed phenotypic differences in the level of antibiotic resistance, biofilm formation, and binding to mucin and motility. According to PFGE, four isolates were sequenced and antibiotic resistance genes as well as virulence factors genes were analyzed in these genomes. The results of this study represent the first report on virulence potential of MDR A. baumannii from hospital in Serbia.
T2  - Frontiers in Microbiology
T2  - Frontiers in Microbiology
T1  - Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia
VL  - 14
DO  - 10.3389/fmicb.2023.1094184
ER  - 

@article{
author = "Novović, Katarina and Kuzmanović Nedeljković, Snežana and Poledica, Mirjana and Nikolić, Gordana and Grujić, Bojana and Jovčić, Branko and Kojić, Milan and Filipić, Brankica",
year = "2023",
abstract = "Since the WHO declared the COVID-19 pandemic in March 2020, the disease has spread rapidly leading to overload of the health system and many of the patients infected with SARS-CoV-2 needed to be admitted to the intensive care unit (ICU). Around 10% of patients with the severe manifestation of COVID-19 need noninvasive or invasive mechanical ventilation, which represent a risk factor for Acinetobacter baumannii superinfection. The 64 A. baumannii isolates were recovered from COVID-19 patients admitted to ICU at General Hospital “Dr Laza K. Lazarević” Šabac, Serbia, during the period from December 2020 to February 2021. All patients required mechanical ventilation and mortality rate was 100%. The goal of this study was to evaluate antibiotic resistance profiles and virulence potential of A. baumannii isolates recovered from patients with severe form of COVID-19 who had a need for mechanical ventilation. All tested A. baumannii isolates (n = 64) were sensitive to colistin, while resistant to meropenem, imipenem, gentamicin, tobramycin, and levofloxacin according to the broth microdilution method and MDR phenotype was confirmed. In all tested isolates, representatives of international clone 2 (IC2) classified by multiplex PCR for clonal lineage identification, blaAmpC, blaOXA-51, and blaOXA-23 genes were present, as well as ISAba1 insertion sequence upstream of blaOXA-23. Clonal distribution of one dominant strain was found, but individual strains showed phenotypic differences in the level of antibiotic resistance, biofilm formation, and binding to mucin and motility. According to PFGE, four isolates were sequenced and antibiotic resistance genes as well as virulence factors genes were analyzed in these genomes. The results of this study represent the first report on virulence potential of MDR A. baumannii from hospital in Serbia.",
journal = "Frontiers in Microbiology, Frontiers in Microbiology",
title = "Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia",
volume = "14",
doi = "10.3389/fmicb.2023.1094184"
}

Novović, K., Kuzmanović Nedeljković, S., Poledica, M., Nikolić, G., Grujić, B., Jovčić, B., Kojić, M.,& Filipić, B.. (2023). Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. in Frontiers in Microbiology, 14.
https://doi.org/10.3389/fmicb.2023.1094184

Novović K, Kuzmanović Nedeljković S, Poledica M, Nikolić G, Grujić B, Jovčić B, Kojić M, Filipić B. Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia. in Frontiers in Microbiology. 2023;14.
doi:10.3389/fmicb.2023.1094184 .

Novović, Katarina, Kuzmanović Nedeljković, Snežana, Poledica, Mirjana, Nikolić, Gordana, Grujić, Bojana, Jovčić, Branko, Kojić, Milan, Filipić, Brankica, "Virulence potential of multidrug-resistant Acinetobacter baumannii isolates from COVID-19 patients on mechanical ventilation: The first report from Serbia" in Frontiers in Microbiology, 14 (2023),
https://doi.org/10.3389/fmicb.2023.1094184 . .

TY  - JOUR
AU  - Ušjak, Dušan
AU  - Novović, Katarina
AU  - Ivković, Branka
AU  - Tomić, Branko
AU  - Đorđević, Valentina
AU  - Milenković, Marina
PY  - 2023
UR  - https://doi.org/10.1080/08927014.2023.2215693
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1896
AB  - Biofilm production facilitates microbial colonization of wounds and catheters. Acinetobacter baumannii produces high levels of biofilm and causes difficult-to-treat nosocomial infections. Candida albicans is another strong biofilm producer which may facilitate A. baumannii adhesion by providing hyphae-mediated OmpA-binding sites. Here we tested the potential of 2′-hydroxychalcones to inhibit dual-species biofilm production of A. baumannii and Candida spp., and further predicted the mechanism of structure-related difference in activity. The results suggest that 2′-hydroxychalcones exhibit potent activity against Candida spp./A. baumannii dual-species biofilm production. Particularly active was trifluoromethyl-substituted derivative (p-CF3), which decreased C. albicans/A. baumannii biomass produced on vein-indwelling parts of the central venous catheterization set by up to 99%. Further, higher OmpA-binding affinity was also calculated for p-CF3, which together with demonstrated significant ompA-downregulating activity, suggests that superior antibiofilm activity of this chalcone against the tested dual-species community of A. baumannii is mediated through the OmpA.
T2  - Biofouling
T2  - Biofouling
T1  - Targeting outer membrane protein A (OmpA) – inhibitory effect of 2′-hydroxychalcone derivatives on Acinetobacter baumannii and Candida albicans dual-species biofilm formation
EP  - 11
SP  - 1
DO  - 10.1080/08927014.2023.2215693
ER  - 

@article{
author = "Ušjak, Dušan and Novović, Katarina and Ivković, Branka and Tomić, Branko and Đorđević, Valentina and Milenković, Marina",
year = "2023",
abstract = "Biofilm production facilitates microbial colonization of wounds and catheters. Acinetobacter baumannii produces high levels of biofilm and causes difficult-to-treat nosocomial infections. Candida albicans is another strong biofilm producer which may facilitate A. baumannii adhesion by providing hyphae-mediated OmpA-binding sites. Here we tested the potential of 2′-hydroxychalcones to inhibit dual-species biofilm production of A. baumannii and Candida spp., and further predicted the mechanism of structure-related difference in activity. The results suggest that 2′-hydroxychalcones exhibit potent activity against Candida spp./A. baumannii dual-species biofilm production. Particularly active was trifluoromethyl-substituted derivative (p-CF3), which decreased C. albicans/A. baumannii biomass produced on vein-indwelling parts of the central venous catheterization set by up to 99%. Further, higher OmpA-binding affinity was also calculated for p-CF3, which together with demonstrated significant ompA-downregulating activity, suggests that superior antibiofilm activity of this chalcone against the tested dual-species community of A. baumannii is mediated through the OmpA.",
journal = "Biofouling, Biofouling",
title = "Targeting outer membrane protein A (OmpA) – inhibitory effect of 2′-hydroxychalcone derivatives on Acinetobacter baumannii and Candida albicans dual-species biofilm formation",
pages = "11-1",
doi = "10.1080/08927014.2023.2215693"
}

Ušjak, D., Novović, K., Ivković, B., Tomić, B., Đorđević, V.,& Milenković, M.. (2023). Targeting outer membrane protein A (OmpA) – inhibitory effect of 2′-hydroxychalcone derivatives on Acinetobacter baumannii and Candida albicans dual-species biofilm formation. in Biofouling, 1-11.
https://doi.org/10.1080/08927014.2023.2215693

Ušjak D, Novović K, Ivković B, Tomić B, Đorđević V, Milenković M. Targeting outer membrane protein A (OmpA) – inhibitory effect of 2′-hydroxychalcone derivatives on Acinetobacter baumannii and Candida albicans dual-species biofilm formation. in Biofouling. 2023;:1-11.
doi:10.1080/08927014.2023.2215693 .

Ušjak, Dušan, Novović, Katarina, Ivković, Branka, Tomić, Branko, Đorđević, Valentina, Milenković, Marina, "Targeting outer membrane protein A (OmpA) – inhibitory effect of 2′-hydroxychalcone derivatives on Acinetobacter baumannii and Candida albicans dual-species biofilm formation" in Biofouling (2023):1-11,
https://doi.org/10.1080/08927014.2023.2215693 . .

TY  - JOUR
AU  - Novović, Katarina
AU  - Malešević, Milka
AU  - Dinić, Miroslav
AU  - Gardijan, Lazar
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1525
AB  - Signal transduction systems are the key players of bacterial adaptation and survival. The orthodox two-component signal transduction systems perceive diverse environmental stimuli and their regulatory response leads to cellular changes. Although rarely described, the unorthodox three-component systems are also implemented in the regulation of major bacterial behavior such as the virulence of clinically relevant pathogen P. aeruginosa. Previously, we described a novel three-component system in P. capeferrum WCS358 (RclSAR) where the sensor kinase RclS stimulates the intI1 transcription in stationary growth phase. In this study, using rclS knock-out mutant, we identified RclSAR regulon in P. capeferrum WCS358. The RNA sequencing revealed that activity of RclSAR signal transduction system is growth phase dependent with more pronounced regulatory potential in early stages of growth. Transcriptional analysis emphasized the role of RclSAR in global regulation and indicated the involvement of this system in regulation of diverse cellular activities such as RNA binding and metabolic and biocontrol processes. Importantly, phenotypic comparison of WCS358 wild type and Delta rclS mutant showed that RclS sensor kinase contributes to modulation of antibiotic resistance, production of AHLs and siderophore as well as host cell adherence and cytotoxicity. Finally, we proposed the improved model of interplay between RclSAR, RpoS and LasIR regulatory systems in P. capeferrum WCS358.
PB  - MDPI, Basel
T2  - International Journal of Molecular Sciences
T1  - RclS Sensor Kinase Modulates Virulence of Pseudomonas capeferrum
IS  - 15
VL  - 23
DO  - 10.3390/ijms23158232
ER  - 

@article{
author = "Novović, Katarina and Malešević, Milka and Dinić, Miroslav and Gardijan, Lazar and Kojić, Milan and Jovčić, Branko",
year = "2022",
abstract = "Signal transduction systems are the key players of bacterial adaptation and survival. The orthodox two-component signal transduction systems perceive diverse environmental stimuli and their regulatory response leads to cellular changes. Although rarely described, the unorthodox three-component systems are also implemented in the regulation of major bacterial behavior such as the virulence of clinically relevant pathogen P. aeruginosa. Previously, we described a novel three-component system in P. capeferrum WCS358 (RclSAR) where the sensor kinase RclS stimulates the intI1 transcription in stationary growth phase. In this study, using rclS knock-out mutant, we identified RclSAR regulon in P. capeferrum WCS358. The RNA sequencing revealed that activity of RclSAR signal transduction system is growth phase dependent with more pronounced regulatory potential in early stages of growth. Transcriptional analysis emphasized the role of RclSAR in global regulation and indicated the involvement of this system in regulation of diverse cellular activities such as RNA binding and metabolic and biocontrol processes. Importantly, phenotypic comparison of WCS358 wild type and Delta rclS mutant showed that RclS sensor kinase contributes to modulation of antibiotic resistance, production of AHLs and siderophore as well as host cell adherence and cytotoxicity. Finally, we proposed the improved model of interplay between RclSAR, RpoS and LasIR regulatory systems in P. capeferrum WCS358.",
publisher = "MDPI, Basel",
journal = "International Journal of Molecular Sciences",
title = "RclS Sensor Kinase Modulates Virulence of Pseudomonas capeferrum",
number = "15",
volume = "23",
doi = "10.3390/ijms23158232"
}

Novović, K., Malešević, M., Dinić, M., Gardijan, L., Kojić, M.,& Jovčić, B.. (2022). RclS Sensor Kinase Modulates Virulence of Pseudomonas capeferrum. in International Journal of Molecular Sciences
MDPI, Basel., 23(15).
https://doi.org/10.3390/ijms23158232

Novović K, Malešević M, Dinić M, Gardijan L, Kojić M, Jovčić B. RclS Sensor Kinase Modulates Virulence of Pseudomonas capeferrum. in International Journal of Molecular Sciences. 2022;23(15).
doi:10.3390/ijms23158232 .

Novović, Katarina, Malešević, Milka, Dinić, Miroslav, Gardijan, Lazar, Kojić, Milan, Jovčić, Branko, "RclS Sensor Kinase Modulates Virulence of Pseudomonas capeferrum" in International Journal of Molecular Sciences, 23, no. 15 (2022),
https://doi.org/10.3390/ijms23158232 . .

TY  - JOUR
AU  - Ivanov, Marija
AU  - Novović, Katarina
AU  - Malešević, Milka
AU  - Dinić, Miroslav
AU  - Stojković, Dejan
AU  - Jovčić, Branko
AU  - Soković, Marina
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1566
AB  - The rising incidence of antibiotic resistant microorganisms urges novel antimicrobials development with polyphenols as appealing potential therapeutics. We aimed to reveal the most promising polyphenols among hesperetin, hesperidin, naringenin, naringin, taxifolin, rutin, isoquercitrin, morin, chlorogenic acid, ferulic acid, p-coumaric acid, and gallic acid based on antimicrobial capacity, antibiofilm potential, and lack of cytotoxicity towards HaCaT, and to further test its antivirulence mechanisms. Although the majority of studied polyphenols were able to inhibit bacterial growth and biofilm formation, the most promising activities were observed for rutin. Further investigation proved rutin's ability to prevent/eradicate Pseudomonas aeruginosa and MRSA urinary catheter biofilms. Besides reduction of biofilm biomass, rutin antibiofilm mechanisms included reduction of cell viability, exopolysaccharide, and extracellular DNA levels. Moderate reduction of bacterial adhesion to human keratinocytes upon treatment was observed. Rutin antivirulence mechanisms included an impact on P. aeruginosa protease, pyocyanin, rhamnolipid, and elastase production and the downregulation of the lasI, lasR, rhlI, rhlR, pqsA and mvfR genes. Rutin also interfered with membrane permeability. Polyphenols could repress antibiotic resistant bacteria. Rutin has shown wide antimicrobial and antibiofilm capacity employing a range of mechanisms that might be used for the development of novel antimicrobials.
PB  - MDPI, Basel
T2  - Pharmaceuticals
T1  - Polyphenols as Inhibitors of Antibiotic Resistant Bacteria-Mechanisms Underlying Rutin Interference with Bacterial Virulence
IS  - 3
VL  - 15
DO  - 10.3390/ph15030385
ER  - 

@article{
author = "Ivanov, Marija and Novović, Katarina and Malešević, Milka and Dinić, Miroslav and Stojković, Dejan and Jovčić, Branko and Soković, Marina",
year = "2022",
abstract = "The rising incidence of antibiotic resistant microorganisms urges novel antimicrobials development with polyphenols as appealing potential therapeutics. We aimed to reveal the most promising polyphenols among hesperetin, hesperidin, naringenin, naringin, taxifolin, rutin, isoquercitrin, morin, chlorogenic acid, ferulic acid, p-coumaric acid, and gallic acid based on antimicrobial capacity, antibiofilm potential, and lack of cytotoxicity towards HaCaT, and to further test its antivirulence mechanisms. Although the majority of studied polyphenols were able to inhibit bacterial growth and biofilm formation, the most promising activities were observed for rutin. Further investigation proved rutin's ability to prevent/eradicate Pseudomonas aeruginosa and MRSA urinary catheter biofilms. Besides reduction of biofilm biomass, rutin antibiofilm mechanisms included reduction of cell viability, exopolysaccharide, and extracellular DNA levels. Moderate reduction of bacterial adhesion to human keratinocytes upon treatment was observed. Rutin antivirulence mechanisms included an impact on P. aeruginosa protease, pyocyanin, rhamnolipid, and elastase production and the downregulation of the lasI, lasR, rhlI, rhlR, pqsA and mvfR genes. Rutin also interfered with membrane permeability. Polyphenols could repress antibiotic resistant bacteria. Rutin has shown wide antimicrobial and antibiofilm capacity employing a range of mechanisms that might be used for the development of novel antimicrobials.",
publisher = "MDPI, Basel",
journal = "Pharmaceuticals",
title = "Polyphenols as Inhibitors of Antibiotic Resistant Bacteria-Mechanisms Underlying Rutin Interference with Bacterial Virulence",
number = "3",
volume = "15",
doi = "10.3390/ph15030385"
}

Ivanov, M., Novović, K., Malešević, M., Dinić, M., Stojković, D., Jovčić, B.,& Soković, M.. (2022). Polyphenols as Inhibitors of Antibiotic Resistant Bacteria-Mechanisms Underlying Rutin Interference with Bacterial Virulence. in Pharmaceuticals
MDPI, Basel., 15(3).
https://doi.org/10.3390/ph15030385

Ivanov M, Novović K, Malešević M, Dinić M, Stojković D, Jovčić B, Soković M. Polyphenols as Inhibitors of Antibiotic Resistant Bacteria-Mechanisms Underlying Rutin Interference with Bacterial Virulence. in Pharmaceuticals. 2022;15(3).
doi:10.3390/ph15030385 .

Ivanov, Marija, Novović, Katarina, Malešević, Milka, Dinić, Miroslav, Stojković, Dejan, Jovčić, Branko, Soković, Marina, "Polyphenols as Inhibitors of Antibiotic Resistant Bacteria-Mechanisms Underlying Rutin Interference with Bacterial Virulence" in Pharmaceuticals, 15, no. 3 (2022),
https://doi.org/10.3390/ph15030385 . .

TY  - JOUR
AU  - Novović, Katarina
AU  - Malešević, Milka
AU  - Gardijan, Lazar
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1572
AB  - The rapid and appropriate response of Pseudomonas spp. to environmental fluctuations has been enabled by numerous signal transduction regulatory systems. Regulatory systems in Pseudomonas aeruginosa are organized in a complex network which provides quick and fine-tuned cellular response through regulation of virulence and antibiotic resistance determinants production. Mobile integrons represent genetic elements included in the rapid dissemination of multiple antibiotic resistance determinants. The key factor of integron dynamics is enzyme integrase. So far, global regulators LexA, RpoS and PsrA have been recognized as regulators of the intI1 transcription. In this study, we discovered novel activator of the intI1 transcription, sensor kinase RclS, in Pseudomonas putida WCS358. This regulation is limited to stationary growth phase and appears to be indirect, at least through regulation of the rpoS expression. Sensor kinase RclS is a part of novel three-component system Rcl (Roc-like) together with two response regulators, RclR and RclA. RclS acted as a negative regulator of the rclA transcription, while the role in the rclR transcription regulation could not be defined. The RclSAR regulatory system seems to be a part of complex intI1 regulatory network which includes major stress response (SOS and RpoS) regulons.
PB  - Elsevier, Amsterdam
T2  - Research in Microbiology
T1  - Novel RclSAR three-component system regulates expression of the intI1 gene in the stationary growth phase
IS  - 1-2
VL  - 173
DO  - 10.1016/j.resmic.2021.103885
ER  - 

@article{
author = "Novović, Katarina and Malešević, Milka and Gardijan, Lazar and Kojić, Milan and Jovčić, Branko",
year = "2022",
abstract = "The rapid and appropriate response of Pseudomonas spp. to environmental fluctuations has been enabled by numerous signal transduction regulatory systems. Regulatory systems in Pseudomonas aeruginosa are organized in a complex network which provides quick and fine-tuned cellular response through regulation of virulence and antibiotic resistance determinants production. Mobile integrons represent genetic elements included in the rapid dissemination of multiple antibiotic resistance determinants. The key factor of integron dynamics is enzyme integrase. So far, global regulators LexA, RpoS and PsrA have been recognized as regulators of the intI1 transcription. In this study, we discovered novel activator of the intI1 transcription, sensor kinase RclS, in Pseudomonas putida WCS358. This regulation is limited to stationary growth phase and appears to be indirect, at least through regulation of the rpoS expression. Sensor kinase RclS is a part of novel three-component system Rcl (Roc-like) together with two response regulators, RclR and RclA. RclS acted as a negative regulator of the rclA transcription, while the role in the rclR transcription regulation could not be defined. The RclSAR regulatory system seems to be a part of complex intI1 regulatory network which includes major stress response (SOS and RpoS) regulons.",
publisher = "Elsevier, Amsterdam",
journal = "Research in Microbiology",
title = "Novel RclSAR three-component system regulates expression of the intI1 gene in the stationary growth phase",
number = "1-2",
volume = "173",
doi = "10.1016/j.resmic.2021.103885"
}

Novović, K., Malešević, M., Gardijan, L., Kojić, M.,& Jovčić, B.. (2022). Novel RclSAR three-component system regulates expression of the intI1 gene in the stationary growth phase. in Research in Microbiology
Elsevier, Amsterdam., 173(1-2).
https://doi.org/10.1016/j.resmic.2021.103885

Novović K, Malešević M, Gardijan L, Kojić M, Jovčić B. Novel RclSAR three-component system regulates expression of the intI1 gene in the stationary growth phase. in Research in Microbiology. 2022;173(1-2).
doi:10.1016/j.resmic.2021.103885 .

Novović, Katarina, Malešević, Milka, Gardijan, Lazar, Kojić, Milan, Jovčić, Branko, "Novel RclSAR three-component system regulates expression of the intI1 gene in the stationary growth phase" in Research in Microbiology, 173, no. 1-2 (2022),
https://doi.org/10.1016/j.resmic.2021.103885 . .

TY  - JOUR
AU  - Filipić, Brankica
AU  - Malešević, Milka
AU  - Vasiljević, Zorica
AU  - Novović, Katarina
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1778
AB  - Trimethoprim-sulfamethoxazole (SXT) is the preferable treatment option of the infections caused by Achromobacter spp. Our study aimed to analyze the SXT resistance of 98 Achromobacter spp. isolates from pediatric patients, among which 33 isolates were SXT-resistant. The presence of intI1 was screened by PCR and genome sequence analyses. The intI1 gene was detected in 10 of SXT-resistant isolates that had shorter intI1 PCR fragments named intI1S. Structural changes in intI1S were confirmed by genome sequencing and analyses which revealed 86 amino acids deletion in IntI1S protein compared to canonical IntI1 protein. All IntI1S isolates were of non-CF origin. Pan-genome analysis of intI1S bearing A. xylosoxidans isolates comprised 9052 genes, with the core genome consisting of 5455 protein-coding genes. Results in this study indicate that IntI1S isolates were derived from clinical settings and that cystic fibrosis (CF) patients were potential reservoirs for healthcare-associated infections that occurred in non-CF patients.
PB  - Springer Science and Business Media B.V.
T2  - Folia Microbiologica
T1  - Comparative genomics of trimethoprim-sulfamethoxazole-resistant Achromobacter xylosoxidans clinical isolates from Serbia reveals shortened variant of class 1 integron integrase gene
DO  - 10.1007/s12223-022-01026-8
ER  - 

@article{
author = "Filipić, Brankica and Malešević, Milka and Vasiljević, Zorica and Novović, Katarina and Kojić, Milan and Jovčić, Branko",
year = "2022",
abstract = "Trimethoprim-sulfamethoxazole (SXT) is the preferable treatment option of the infections caused by Achromobacter spp. Our study aimed to analyze the SXT resistance of 98 Achromobacter spp. isolates from pediatric patients, among which 33 isolates were SXT-resistant. The presence of intI1 was screened by PCR and genome sequence analyses. The intI1 gene was detected in 10 of SXT-resistant isolates that had shorter intI1 PCR fragments named intI1S. Structural changes in intI1S were confirmed by genome sequencing and analyses which revealed 86 amino acids deletion in IntI1S protein compared to canonical IntI1 protein. All IntI1S isolates were of non-CF origin. Pan-genome analysis of intI1S bearing A. xylosoxidans isolates comprised 9052 genes, with the core genome consisting of 5455 protein-coding genes. Results in this study indicate that IntI1S isolates were derived from clinical settings and that cystic fibrosis (CF) patients were potential reservoirs for healthcare-associated infections that occurred in non-CF patients.",
publisher = "Springer Science and Business Media B.V.",
journal = "Folia Microbiologica",
title = "Comparative genomics of trimethoprim-sulfamethoxazole-resistant Achromobacter xylosoxidans clinical isolates from Serbia reveals shortened variant of class 1 integron integrase gene",
doi = "10.1007/s12223-022-01026-8"
}

Filipić, B., Malešević, M., Vasiljević, Z., Novović, K., Kojić, M.,& Jovčić, B.. (2022). Comparative genomics of trimethoprim-sulfamethoxazole-resistant Achromobacter xylosoxidans clinical isolates from Serbia reveals shortened variant of class 1 integron integrase gene. in Folia Microbiologica
Springer Science and Business Media B.V...
https://doi.org/10.1007/s12223-022-01026-8

Filipić B, Malešević M, Vasiljević Z, Novović K, Kojić M, Jovčić B. Comparative genomics of trimethoprim-sulfamethoxazole-resistant Achromobacter xylosoxidans clinical isolates from Serbia reveals shortened variant of class 1 integron integrase gene. in Folia Microbiologica. 2022;.
doi:10.1007/s12223-022-01026-8 .

Filipić, Brankica, Malešević, Milka, Vasiljević, Zorica, Novović, Katarina, Kojić, Milan, Jovčić, Branko, "Comparative genomics of trimethoprim-sulfamethoxazole-resistant Achromobacter xylosoxidans clinical isolates from Serbia reveals shortened variant of class 1 integron integrase gene" in Folia Microbiologica (2022),
https://doi.org/10.1007/s12223-022-01026-8 . .

TY  - JOUR
AU  - Đorđević, Neda O.
AU  - Stanisavljević, Nemanja
AU  - Todorovic Vukotić, Nevena
AU  - Novović, Katarina
AU  - Zakula, Jelena J.
AU  - Stanković, Dalibor
AU  - Pajović, Snežana B.
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1584
AB  - The beneficial effect of moderate wine consumption is attributed to its micronutrients, especially polyphenols and largely depends on the digestion process. This work aimed to examine the influence of in vitro simulated digestion in the presence of complex food matrix on antioxidant and cytotoxic activity of red wine. The obtained results showed that total phenolic content of wine sample after in vitro digestion was higher compared to undigested wine, while the antioxidant activity of these samples was similar before and after digestion. Furthermore, it has been noticed that digested wine showed cytotoxic activity on SKBR3 breast adenocarcinoma cells near 20% after 72 h of treatment. This pioneering study that examined biological potential of in vitro digested wine in the presence of complex food matrix indicate that antioxidant and cytotoxic activity of red wine is preserved after digestion.
PB  - Taylor & Francis Ltd, Abingdon
T2  - Natural Product Research
T1  - Antioxidant and cytotoxic activity of red wine after in vitro simulated digestion in the presence of complex food matrix
DO  - 10.1080/14786419.2022.2095380
ER  - 

@article{
author = "Đorđević, Neda O. and Stanisavljević, Nemanja and Todorovic Vukotić, Nevena and Novović, Katarina and Zakula, Jelena J. and Stanković, Dalibor and Pajović, Snežana B.",
year = "2022",
abstract = "The beneficial effect of moderate wine consumption is attributed to its micronutrients, especially polyphenols and largely depends on the digestion process. This work aimed to examine the influence of in vitro simulated digestion in the presence of complex food matrix on antioxidant and cytotoxic activity of red wine. The obtained results showed that total phenolic content of wine sample after in vitro digestion was higher compared to undigested wine, while the antioxidant activity of these samples was similar before and after digestion. Furthermore, it has been noticed that digested wine showed cytotoxic activity on SKBR3 breast adenocarcinoma cells near 20% after 72 h of treatment. This pioneering study that examined biological potential of in vitro digested wine in the presence of complex food matrix indicate that antioxidant and cytotoxic activity of red wine is preserved after digestion.",
publisher = "Taylor & Francis Ltd, Abingdon",
journal = "Natural Product Research",
title = "Antioxidant and cytotoxic activity of red wine after in vitro simulated digestion in the presence of complex food matrix",
doi = "10.1080/14786419.2022.2095380"
}

Đorđević, N. O., Stanisavljević, N., Todorovic Vukotić, N., Novović, K., Zakula, J. J., Stanković, D.,& Pajović, S. B.. (2022). Antioxidant and cytotoxic activity of red wine after in vitro simulated digestion in the presence of complex food matrix. in Natural Product Research
Taylor & Francis Ltd, Abingdon..
https://doi.org/10.1080/14786419.2022.2095380

Đorđević NO, Stanisavljević N, Todorovic Vukotić N, Novović K, Zakula JJ, Stanković D, Pajović SB. Antioxidant and cytotoxic activity of red wine after in vitro simulated digestion in the presence of complex food matrix. in Natural Product Research. 2022;.
doi:10.1080/14786419.2022.2095380 .

Đorđević, Neda O., Stanisavljević, Nemanja, Todorovic Vukotić, Nevena, Novović, Katarina, Zakula, Jelena J., Stanković, Dalibor, Pajović, Snežana B., "Antioxidant and cytotoxic activity of red wine after in vitro simulated digestion in the presence of complex food matrix" in Natural Product Research (2022),
https://doi.org/10.1080/14786419.2022.2095380 . .

TY  - JOUR
AU  - Ljubić, Verica
AU  - Milosević, Milena
AU  - Cvetković, Slobodan
AU  - Stojanović, Marijana
AU  - Novović, Katarina
AU  - Dinić, Miroslav
AU  - Popović, Mina
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1523
AB  - As one of the most promising groups of microbes, lactic acid bacteria (LAB) can synthesize metabolites that can be used in different industries over the world, mainly in the pharmaceutical, food, and dairy industries. In this study, a novel exopolysaccharide was extracted and isolated from the probiotic strain Lactobacillus reuteri B2, and assessed on biological activity and its possible application as a biosorbent for the removal of Ni2+ ions from contaminated water. New exopolysaccharide was characterized using FTIR, SEM, XRD, NMR, MALDI-TOF MS, and TGA/DTG analysis. Biological assays included antioxidative activity, cytotoxic assay, and adhesion assay of L. reuteri B2 to HT29 cells. Our hypothesis was that if this exopolysaccharide is nontoxic, it can be used as a novel biomaterial for the possible application of the removal of Ni2+ ions from contaminated water. The scavenging effect of nontoxic exopolysaccharide was 76% at 2 mg/mL using ABTS assay, in biological assays, while the removal efficiency of nickel from the aqueous solution was 92.96% in biosorption study. According to these results, this exopolysaccharide can be considered a very promising biomaterial for potential application in different industries, from pharmacy to wastewater treatments.
PB  - Springer Heidelberg, Heidelberg
T2  - Biomass Conversion and Biorefinery
T1  - The new exopolysaccharide produced by the probiotic strain L. reuteri B2: extraction, biological properties, and possible application for Ni2+ ion removal from the contaminated water
DO  - 10.1007/s13399-022-03292-5
ER  - 

@article{
author = "Ljubić, Verica and Milosević, Milena and Cvetković, Slobodan and Stojanović, Marijana and Novović, Katarina and Dinić, Miroslav and Popović, Mina",
year = "2022",
abstract = "As one of the most promising groups of microbes, lactic acid bacteria (LAB) can synthesize metabolites that can be used in different industries over the world, mainly in the pharmaceutical, food, and dairy industries. In this study, a novel exopolysaccharide was extracted and isolated from the probiotic strain Lactobacillus reuteri B2, and assessed on biological activity and its possible application as a biosorbent for the removal of Ni2+ ions from contaminated water. New exopolysaccharide was characterized using FTIR, SEM, XRD, NMR, MALDI-TOF MS, and TGA/DTG analysis. Biological assays included antioxidative activity, cytotoxic assay, and adhesion assay of L. reuteri B2 to HT29 cells. Our hypothesis was that if this exopolysaccharide is nontoxic, it can be used as a novel biomaterial for the possible application of the removal of Ni2+ ions from contaminated water. The scavenging effect of nontoxic exopolysaccharide was 76% at 2 mg/mL using ABTS assay, in biological assays, while the removal efficiency of nickel from the aqueous solution was 92.96% in biosorption study. According to these results, this exopolysaccharide can be considered a very promising biomaterial for potential application in different industries, from pharmacy to wastewater treatments.",
publisher = "Springer Heidelberg, Heidelberg",
journal = "Biomass Conversion and Biorefinery",
title = "The new exopolysaccharide produced by the probiotic strain L. reuteri B2: extraction, biological properties, and possible application for Ni2+ ion removal from the contaminated water",
doi = "10.1007/s13399-022-03292-5"
}

Ljubić, V., Milosević, M., Cvetković, S., Stojanović, M., Novović, K., Dinić, M.,& Popović, M.. (2022). The new exopolysaccharide produced by the probiotic strain L. reuteri B2: extraction, biological properties, and possible application for Ni2+ ion removal from the contaminated water. in Biomass Conversion and Biorefinery
Springer Heidelberg, Heidelberg..
https://doi.org/10.1007/s13399-022-03292-5

Ljubić V, Milosević M, Cvetković S, Stojanović M, Novović K, Dinić M, Popović M. The new exopolysaccharide produced by the probiotic strain L. reuteri B2: extraction, biological properties, and possible application for Ni2+ ion removal from the contaminated water. in Biomass Conversion and Biorefinery. 2022;.
doi:10.1007/s13399-022-03292-5 .

Ljubić, Verica, Milosević, Milena, Cvetković, Slobodan, Stojanović, Marijana, Novović, Katarina, Dinić, Miroslav, Popović, Mina, "The new exopolysaccharide produced by the probiotic strain L. reuteri B2: extraction, biological properties, and possible application for Ni2+ ion removal from the contaminated water" in Biomass Conversion and Biorefinery (2022),
https://doi.org/10.1007/s13399-022-03292-5 . .

TY  - JOUR
AU  - Ušjak, Dušan
AU  - Novović, Katarina
AU  - Filipić, Brankica
AU  - Kojić, Milan
AU  - Filipović, Nenad
AU  - Stevanović, Magdalena
AU  - Milenković, Marina T.
PY  - 2022
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1600
AB  - Aims To investigate the synergistic activity of colistin and selenium nanoparticles (SeNPs) against pandrug-resistant (PDR) Ac. baumannii. Methods and Results Chequerboard and time-kill assays were employed to explore the potential synergistic interactions between colistin and SeNPs against Ac. baumannii isolates (8), previously determined as colistin-resistant (MIC range 16-256 mu g ml(-1)). Also, whole-genome sequencing (WGS) and gene expression analyses were used to elucidate the mechanisms of colistin resistance. Exceptionally strong synergistic activity (FICI range 0.004-0.035) of colistin and SeNPs against colistin-resistant isolates was revealed. Colistin (0.5 or 1 mu g ml(-1)) used in combination with SeNPs (0.5 mu g ml(-1)) was able to reduce initial inoculum during the first 4 h of incubation, in contrast to colistin (0.5, 1 or 2 mu g ml(-1)) alone. Conclusions These findings propose colistin/SeNPs combination as a new option to fight PDR Ac. baumannii, the therapeutic possibilities of which should be proved in future in vivo studies. Significance and Impact of Study Here we present the first evidence of synergy between colistin and selenium compounds against bacteria in general. Also, WGS and gene expression analyses provide some new insights into Ac. baumannii colistin resistance mechanisms.
PB  - Wiley, Hoboken
T2  - Journal of Applied Microbiology
T1  - In vitro colistin susceptibility of pandrug-resistant Ac. baumannii is restored in the presence of selenium nanoparticles
EP  - 1206
IS  - 3
SP  - 1197
VL  - 133
DO  - 10.1111/jam.15638
ER  - 

@article{
author = "Ušjak, Dušan and Novović, Katarina and Filipić, Brankica and Kojić, Milan and Filipović, Nenad and Stevanović, Magdalena and Milenković, Marina T.",
year = "2022",
abstract = "Aims To investigate the synergistic activity of colistin and selenium nanoparticles (SeNPs) against pandrug-resistant (PDR) Ac. baumannii. Methods and Results Chequerboard and time-kill assays were employed to explore the potential synergistic interactions between colistin and SeNPs against Ac. baumannii isolates (8), previously determined as colistin-resistant (MIC range 16-256 mu g ml(-1)). Also, whole-genome sequencing (WGS) and gene expression analyses were used to elucidate the mechanisms of colistin resistance. Exceptionally strong synergistic activity (FICI range 0.004-0.035) of colistin and SeNPs against colistin-resistant isolates was revealed. Colistin (0.5 or 1 mu g ml(-1)) used in combination with SeNPs (0.5 mu g ml(-1)) was able to reduce initial inoculum during the first 4 h of incubation, in contrast to colistin (0.5, 1 or 2 mu g ml(-1)) alone. Conclusions These findings propose colistin/SeNPs combination as a new option to fight PDR Ac. baumannii, the therapeutic possibilities of which should be proved in future in vivo studies. Significance and Impact of Study Here we present the first evidence of synergy between colistin and selenium compounds against bacteria in general. Also, WGS and gene expression analyses provide some new insights into Ac. baumannii colistin resistance mechanisms.",
publisher = "Wiley, Hoboken",
journal = "Journal of Applied Microbiology",
title = "In vitro colistin susceptibility of pandrug-resistant Ac. baumannii is restored in the presence of selenium nanoparticles",
pages = "1206-1197",
number = "3",
volume = "133",
doi = "10.1111/jam.15638"
}

Ušjak, D., Novović, K., Filipić, B., Kojić, M., Filipović, N., Stevanović, M.,& Milenković, M. T.. (2022). In vitro colistin susceptibility of pandrug-resistant Ac. baumannii is restored in the presence of selenium nanoparticles. in Journal of Applied Microbiology
Wiley, Hoboken., 133(3), 1197-1206.
https://doi.org/10.1111/jam.15638

Ušjak D, Novović K, Filipić B, Kojić M, Filipović N, Stevanović M, Milenković MT. In vitro colistin susceptibility of pandrug-resistant Ac. baumannii is restored in the presence of selenium nanoparticles. in Journal of Applied Microbiology. 2022;133(3):1197-1206.
doi:10.1111/jam.15638 .

Ušjak, Dušan, Novović, Katarina, Filipić, Brankica, Kojić, Milan, Filipović, Nenad, Stevanović, Magdalena, Milenković, Marina T., "In vitro colistin susceptibility of pandrug-resistant Ac. baumannii is restored in the presence of selenium nanoparticles" in Journal of Applied Microbiology, 133, no. 3 (2022):1197-1206,
https://doi.org/10.1111/jam.15638 . .

TY  - JOUR
AU  - Dinić, Miroslav
AU  - Herholz, Marija
AU  - Kacarević, Uros
AU  - Radojević, Dušan
AU  - Novović, Katarina
AU  - Đokić, Jelena
AU  - Trifunović, Aleksandra
AU  - Golić, Nataša
PY  - 2021
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1431
AB  - Gut homeostasis is maintained by the close interaction between commensal intestinal microbiota and the host, affecting the most complex physiological processes, such as aging. Some commensal bacteria with the potential to promote healthy aging arise as attractive candidates for the development of pro-longevity probiotics. Here, we showed that heat-inactivated human commensal Lactobacillus fermentum BGHV110 (BGHV110) extends the lifespan of Caenorhabditis elegans and improves age-related physiological features, including locomotor function and lipid metabolism. Mechanistically, we found that BGHV110 promotes HLH30/TFEB-dependent autophagy to delay aging, as longevity assurance was completely abolished in the mutant lacking HLH-30, a major autophagy regulator in C. elegans. Moreover, we observed that BGHV110 partially decreased the content of lipid droplets in an HLH-30-dependent manner and, at the same time, slightly increased mitochondrial activity. In summary, this study demonstrates that specific factors from commensal bacteria can be used to exploit HLH-30/TFEB-mediated autophagy in order to promote longevity and fitness of the host.
PB  - Impact Journals LLC
T2  - Aging
T1  - Host-commensal interaction promotes health and lifespan in Caenorhabditis elegans through the activation of HLH-30/TFEB-mediated autophagy
EP  - 8054
IS  - 6
SP  - 8040
VL  - 13
DO  - 10.18632/aging.202885
ER  - 

@article{
author = "Dinić, Miroslav and Herholz, Marija and Kacarević, Uros and Radojević, Dušan and Novović, Katarina and Đokić, Jelena and Trifunović, Aleksandra and Golić, Nataša",
year = "2021",
abstract = "Gut homeostasis is maintained by the close interaction between commensal intestinal microbiota and the host, affecting the most complex physiological processes, such as aging. Some commensal bacteria with the potential to promote healthy aging arise as attractive candidates for the development of pro-longevity probiotics. Here, we showed that heat-inactivated human commensal Lactobacillus fermentum BGHV110 (BGHV110) extends the lifespan of Caenorhabditis elegans and improves age-related physiological features, including locomotor function and lipid metabolism. Mechanistically, we found that BGHV110 promotes HLH30/TFEB-dependent autophagy to delay aging, as longevity assurance was completely abolished in the mutant lacking HLH-30, a major autophagy regulator in C. elegans. Moreover, we observed that BGHV110 partially decreased the content of lipid droplets in an HLH-30-dependent manner and, at the same time, slightly increased mitochondrial activity. In summary, this study demonstrates that specific factors from commensal bacteria can be used to exploit HLH-30/TFEB-mediated autophagy in order to promote longevity and fitness of the host.",
publisher = "Impact Journals LLC",
journal = "Aging",
title = "Host-commensal interaction promotes health and lifespan in Caenorhabditis elegans through the activation of HLH-30/TFEB-mediated autophagy",
pages = "8054-8040",
number = "6",
volume = "13",
doi = "10.18632/aging.202885"
}

Dinić, M., Herholz, M., Kacarević, U., Radojević, D., Novović, K., Đokić, J., Trifunović, A.,& Golić, N.. (2021). Host-commensal interaction promotes health and lifespan in Caenorhabditis elegans through the activation of HLH-30/TFEB-mediated autophagy. in Aging
Impact Journals LLC., 13(6), 8040-8054.
https://doi.org/10.18632/aging.202885

Dinić M, Herholz M, Kacarević U, Radojević D, Novović K, Đokić J, Trifunović A, Golić N. Host-commensal interaction promotes health and lifespan in Caenorhabditis elegans through the activation of HLH-30/TFEB-mediated autophagy. in Aging. 2021;13(6):8040-8054.
doi:10.18632/aging.202885 .

Dinić, Miroslav, Herholz, Marija, Kacarević, Uros, Radojević, Dušan, Novović, Katarina, Đokić, Jelena, Trifunović, Aleksandra, Golić, Nataša, "Host-commensal interaction promotes health and lifespan in Caenorhabditis elegans through the activation of HLH-30/TFEB-mediated autophagy" in Aging, 13, no. 6 (2021):8040-8054,
https://doi.org/10.18632/aging.202885 . .

TY  - JOUR
AU  - Velhner, Maja
AU  - Todorović, Dalibor
AU  - Novović, Katarina
AU  - Jovčić, Branko
AU  - Lazić, Gospava
AU  - Kojić, Milan
AU  - Kehrenberg, Corinna
PY  - 2021
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1445
AB  - Despite common resistance to antimicrobials in Escherichia coli isolates from farm animals in Serbia, no data are currently accessible on its occurrence in E. coli isolated from gulls. Therefore, 67 cloacal swabs and 70 fecal samples from black-headed gulls were investigated for the presence of antibiotic-resistant E. coli isolates. Ninety-nine isolates were obtained during the study. Resistotyping and resistance gene typing has shown that 44 isolates harbor resistance to one or more antibiotics. Multidrug resistance was detected in 24 E. coli isolates. Ten isolates were resistant to extended-spectrum cephalosporin antibiotics and were studied in detail including virulence gene typing, phylogenetic and multilocus sequence typing, and mating. These ten isolates belonged to phylogenetic groups B2 (five isolates), D (four isolates) and B1 (one isolate). Five different sequence types (ST38, ST2307, ST224, ST162 and ST34) were detected in E. coli isolates with AmpC phenotype and genotype. One isolate carried the Inc I2/FIB replicon type plasmid with the bla(CTX-M-1) gene. Nine isolates had bla(CMY-2) genes, which were detected on conjugative plasmids in seven isolates. The virulence genes hly, iroN, iss, ompT and cvaC were detected in one transconjugant. Ten isolates were found to be resistant to ciprofloxacin, whose MIC ranged from 4 to 32 mg/L. Genotyping revealed single or double mutations in the quinolone resistance determining region (QRDR) of the gyrA or gyrA, parC and parE genes, respectively. So, Black-headed gulls from Serbia may be colonized by multidrug-resistant E. coli, some of which are resistant to critically important antibiotics in medicine.
PB  - Springer, Dordrecht
T2  - Veterinary Research Communications
T1  - Characterization of antibiotic resistance in Escherichia coli isolates from Black-headed gulls (Larus ridibundus) present in the city of Novi Sad, Serbia
EP  - 209
IS  - 4
SP  - 199
VL  - 45
DO  - 10.1007/s11259-021-09801-7
ER  - 

@article{
author = "Velhner, Maja and Todorović, Dalibor and Novović, Katarina and Jovčić, Branko and Lazić, Gospava and Kojić, Milan and Kehrenberg, Corinna",
year = "2021",
abstract = "Despite common resistance to antimicrobials in Escherichia coli isolates from farm animals in Serbia, no data are currently accessible on its occurrence in E. coli isolated from gulls. Therefore, 67 cloacal swabs and 70 fecal samples from black-headed gulls were investigated for the presence of antibiotic-resistant E. coli isolates. Ninety-nine isolates were obtained during the study. Resistotyping and resistance gene typing has shown that 44 isolates harbor resistance to one or more antibiotics. Multidrug resistance was detected in 24 E. coli isolates. Ten isolates were resistant to extended-spectrum cephalosporin antibiotics and were studied in detail including virulence gene typing, phylogenetic and multilocus sequence typing, and mating. These ten isolates belonged to phylogenetic groups B2 (five isolates), D (four isolates) and B1 (one isolate). Five different sequence types (ST38, ST2307, ST224, ST162 and ST34) were detected in E. coli isolates with AmpC phenotype and genotype. One isolate carried the Inc I2/FIB replicon type plasmid with the bla(CTX-M-1) gene. Nine isolates had bla(CMY-2) genes, which were detected on conjugative plasmids in seven isolates. The virulence genes hly, iroN, iss, ompT and cvaC were detected in one transconjugant. Ten isolates were found to be resistant to ciprofloxacin, whose MIC ranged from 4 to 32 mg/L. Genotyping revealed single or double mutations in the quinolone resistance determining region (QRDR) of the gyrA or gyrA, parC and parE genes, respectively. So, Black-headed gulls from Serbia may be colonized by multidrug-resistant E. coli, some of which are resistant to critically important antibiotics in medicine.",
publisher = "Springer, Dordrecht",
journal = "Veterinary Research Communications",
title = "Characterization of antibiotic resistance in Escherichia coli isolates from Black-headed gulls (Larus ridibundus) present in the city of Novi Sad, Serbia",
pages = "209-199",
number = "4",
volume = "45",
doi = "10.1007/s11259-021-09801-7"
}

Velhner, M., Todorović, D., Novović, K., Jovčić, B., Lazić, G., Kojić, M.,& Kehrenberg, C.. (2021). Characterization of antibiotic resistance in Escherichia coli isolates from Black-headed gulls (Larus ridibundus) present in the city of Novi Sad, Serbia. in Veterinary Research Communications
Springer, Dordrecht., 45(4), 199-209.
https://doi.org/10.1007/s11259-021-09801-7

Velhner M, Todorović D, Novović K, Jovčić B, Lazić G, Kojić M, Kehrenberg C. Characterization of antibiotic resistance in Escherichia coli isolates from Black-headed gulls (Larus ridibundus) present in the city of Novi Sad, Serbia. in Veterinary Research Communications. 2021;45(4):199-209.
doi:10.1007/s11259-021-09801-7 .

Velhner, Maja, Todorović, Dalibor, Novović, Katarina, Jovčić, Branko, Lazić, Gospava, Kojić, Milan, Kehrenberg, Corinna, "Characterization of antibiotic resistance in Escherichia coli isolates from Black-headed gulls (Larus ridibundus) present in the city of Novi Sad, Serbia" in Veterinary Research Communications, 45, no. 4 (2021):199-209,
https://doi.org/10.1007/s11259-021-09801-7 . .

TY  - JOUR
AU  - Jovčić, Branko
AU  - Novović, Katarina
AU  - Dekić, Svjetlana
AU  - Hrenović, Jasna
PY  - 2021
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1485
AB  - Although the molecular mechanisms of carbapenem resistance of environmental isolates ofAcinetobacter baumanniiare well described, data on the mechanisms of colistin resistance are scarce. In this study, we report the molecular mechanisms of colistin resistance in environmental isolates ofA. baumannii. Seven clinically relevant isolates ofA. baumanniibelonging to ST-2(Pasteur)were recovered from hospital wastewater and wastewater treatment plant. The phenotypic resistance to colistin was confirmed by broth microdilution with minimum inhibitory concentration values ranging from 20 to 160 mg/L. Colistin sulfate and colistimethate sodium showed bactericidal activity against two colistin-heteroresistant isolatesin vitro, but substantially recovery of population was observed after prolonged incubation.In silicogenome analysis revealed nucleotide variations resulting in amino acid changes in LpxC (N286D), LpxD (E117K), PmrB (A138T, R263S, L267W, Q309P, and A444V), and EptA (F166L, I228V, R348K, A370S, and K531T). According to reverse transcription quantitative PCR, all isolates had increased levels ofeptAmRNA and decreased levels oflpxAandlpxDmRNA. Isolates expressed low hydrophobicity, biofilm, and pellicle formation, but showed excellent survival in river water during 50 days of monitoring. Colistin- and pandrug-resistantA. baumanniidisseminated in the environment could represent the source for the occurrence of serious community-acquired infections.
PB  - Mary Ann Liebert, Inc, New Rochelle
T2  - Microbial Drug Resistance
T1  - Colistin Resistance in Environmental Isolates ofAcinetobacter baumannii
EP  - 336
IS  - 3
SP  - 328
VL  - 27
DO  - 10.1089/mdr.2020.0188
ER  - 

@article{
author = "Jovčić, Branko and Novović, Katarina and Dekić, Svjetlana and Hrenović, Jasna",
year = "2021",
abstract = "Although the molecular mechanisms of carbapenem resistance of environmental isolates ofAcinetobacter baumanniiare well described, data on the mechanisms of colistin resistance are scarce. In this study, we report the molecular mechanisms of colistin resistance in environmental isolates ofA. baumannii. Seven clinically relevant isolates ofA. baumanniibelonging to ST-2(Pasteur)were recovered from hospital wastewater and wastewater treatment plant. The phenotypic resistance to colistin was confirmed by broth microdilution with minimum inhibitory concentration values ranging from 20 to 160 mg/L. Colistin sulfate and colistimethate sodium showed bactericidal activity against two colistin-heteroresistant isolatesin vitro, but substantially recovery of population was observed after prolonged incubation.In silicogenome analysis revealed nucleotide variations resulting in amino acid changes in LpxC (N286D), LpxD (E117K), PmrB (A138T, R263S, L267W, Q309P, and A444V), and EptA (F166L, I228V, R348K, A370S, and K531T). According to reverse transcription quantitative PCR, all isolates had increased levels ofeptAmRNA and decreased levels oflpxAandlpxDmRNA. Isolates expressed low hydrophobicity, biofilm, and pellicle formation, but showed excellent survival in river water during 50 days of monitoring. Colistin- and pandrug-resistantA. baumanniidisseminated in the environment could represent the source for the occurrence of serious community-acquired infections.",
publisher = "Mary Ann Liebert, Inc, New Rochelle",
journal = "Microbial Drug Resistance",
title = "Colistin Resistance in Environmental Isolates ofAcinetobacter baumannii",
pages = "336-328",
number = "3",
volume = "27",
doi = "10.1089/mdr.2020.0188"
}

Jovčić, B., Novović, K., Dekić, S.,& Hrenović, J.. (2021). Colistin Resistance in Environmental Isolates ofAcinetobacter baumannii. in Microbial Drug Resistance
Mary Ann Liebert, Inc, New Rochelle., 27(3), 328-336.
https://doi.org/10.1089/mdr.2020.0188

Jovčić B, Novović K, Dekić S, Hrenović J. Colistin Resistance in Environmental Isolates ofAcinetobacter baumannii. in Microbial Drug Resistance. 2021;27(3):328-336.
doi:10.1089/mdr.2020.0188 .

Jovčić, Branko, Novović, Katarina, Dekić, Svjetlana, Hrenović, Jasna, "Colistin Resistance in Environmental Isolates ofAcinetobacter baumannii" in Microbial Drug Resistance, 27, no. 3 (2021):328-336,
https://doi.org/10.1089/mdr.2020.0188 . .

TY  - JOUR
AU  - Ušjak, Dušan
AU  - Dinić, Miroslav
AU  - Novović, Katarina
AU  - Ivković, Branka
AU  - Filipović, Nenad
AU  - Stevanović, Magdalena
AU  - Milenković, Marina T.
PY  - 2021
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1509
AB  - An increasing lack of available therapeutic options against Acinetobacter baumannii urged researchers to seek alternative ways to fight this extremely resistant nosocomial pathogen. Targeting its virulence appears to be a promising strategy, as it offers considerably reduced selection of resistant mutants. In this study, we tested antibiofilm potential of four synthetic chalcone derivatives against A. baumannii. Compound that showed the greatest activity was selected for further evaluation of its antivirulence properties. Real-time PCR was used to evaluate mRNA expression of biofilm-associated virulence factor genes (ompA, bap, abaI) in treated A. baumannii strains. Also, we examined virulence properties related to the expression of these genes, such as fibronectin- and collagen-mediated adhesion, surface motility, and quorum-sensing activity. The results revealed that the expression of all tested genes is downregulated together with the reduction of adhesion and motility. The conclusion is that 2 '-hydroxy-2-methoxychalcone exhibits antivirulence activity against A. baumannii by inhibiting the expression of ompA and bap genes, which is reflected in reduced biofilm formation, adhesion, and surface motility.
PB  - Wiley-V C H Verlag Gmbh, Weinheim
T2  - Chemistry & Biodiversity
T1  - Methoxy-Substituted Hydroxychalcone Reduces Biofilm Production, Adhesion and Surface Motility of Acinetobacter baumannii by Inhibiting ompA Gene Expression
IS  - 1
VL  - 18
DO  - 10.1002/cbdv.202000786
ER  - 

@article{
author = "Ušjak, Dušan and Dinić, Miroslav and Novović, Katarina and Ivković, Branka and Filipović, Nenad and Stevanović, Magdalena and Milenković, Marina T.",
year = "2021",
abstract = "An increasing lack of available therapeutic options against Acinetobacter baumannii urged researchers to seek alternative ways to fight this extremely resistant nosocomial pathogen. Targeting its virulence appears to be a promising strategy, as it offers considerably reduced selection of resistant mutants. In this study, we tested antibiofilm potential of four synthetic chalcone derivatives against A. baumannii. Compound that showed the greatest activity was selected for further evaluation of its antivirulence properties. Real-time PCR was used to evaluate mRNA expression of biofilm-associated virulence factor genes (ompA, bap, abaI) in treated A. baumannii strains. Also, we examined virulence properties related to the expression of these genes, such as fibronectin- and collagen-mediated adhesion, surface motility, and quorum-sensing activity. The results revealed that the expression of all tested genes is downregulated together with the reduction of adhesion and motility. The conclusion is that 2 '-hydroxy-2-methoxychalcone exhibits antivirulence activity against A. baumannii by inhibiting the expression of ompA and bap genes, which is reflected in reduced biofilm formation, adhesion, and surface motility.",
publisher = "Wiley-V C H Verlag Gmbh, Weinheim",
journal = "Chemistry & Biodiversity",
title = "Methoxy-Substituted Hydroxychalcone Reduces Biofilm Production, Adhesion and Surface Motility of Acinetobacter baumannii by Inhibiting ompA Gene Expression",
number = "1",
volume = "18",
doi = "10.1002/cbdv.202000786"
}

Ušjak, D., Dinić, M., Novović, K., Ivković, B., Filipović, N., Stevanović, M.,& Milenković, M. T.. (2021). Methoxy-Substituted Hydroxychalcone Reduces Biofilm Production, Adhesion and Surface Motility of Acinetobacter baumannii by Inhibiting ompA Gene Expression. in Chemistry & Biodiversity
Wiley-V C H Verlag Gmbh, Weinheim., 18(1).
https://doi.org/10.1002/cbdv.202000786

Ušjak D, Dinić M, Novović K, Ivković B, Filipović N, Stevanović M, Milenković MT. Methoxy-Substituted Hydroxychalcone Reduces Biofilm Production, Adhesion and Surface Motility of Acinetobacter baumannii by Inhibiting ompA Gene Expression. in Chemistry & Biodiversity. 2021;18(1).
doi:10.1002/cbdv.202000786 .

Ušjak, Dušan, Dinić, Miroslav, Novović, Katarina, Ivković, Branka, Filipović, Nenad, Stevanović, Magdalena, Milenković, Marina T., "Methoxy-Substituted Hydroxychalcone Reduces Biofilm Production, Adhesion and Surface Motility of Acinetobacter baumannii by Inhibiting ompA Gene Expression" in Chemistry & Biodiversity, 18, no. 1 (2021),
https://doi.org/10.1002/cbdv.202000786 . .

TY  - CONF
AU  - Novović, Katarina
AU  - Jovičić, Branko
PY  - 2021
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1650
PB  - Portugal, Caparica
C3  - 4th International Caparica Congress in antibiotic resistance
T1  - Resolving the hierarchy of class 1 integron integrase gene expression regulation in Pseudomonas spp
EP  - 119
SP  - 119
UR  - https://hdl.handle.net/21.15107/rcub_imagine_1650
ER  - 

@conference{
author = "Novović, Katarina and Jovičić, Branko",
year = "2021",
publisher = "Portugal, Caparica",
journal = "4th International Caparica Congress in antibiotic resistance",
title = "Resolving the hierarchy of class 1 integron integrase gene expression regulation in Pseudomonas spp",
pages = "119-119",
url = "https://hdl.handle.net/21.15107/rcub_imagine_1650"
}

Novović, K.,& Jovičić, B.. (2021). Resolving the hierarchy of class 1 integron integrase gene expression regulation in Pseudomonas spp. in 4th International Caparica Congress in antibiotic resistance
Portugal, Caparica., 119-119.
https://hdl.handle.net/21.15107/rcub_imagine_1650

Novović K, Jovičić B. Resolving the hierarchy of class 1 integron integrase gene expression regulation in Pseudomonas spp. in 4th International Caparica Congress in antibiotic resistance. 2021;:119-119.
https://hdl.handle.net/21.15107/rcub_imagine_1650 .

Novović, Katarina, Jovičić, Branko, "Resolving the hierarchy of class 1 integron integrase gene expression regulation in Pseudomonas spp" in 4th International Caparica Congress in antibiotic resistance (2021):119-119,
https://hdl.handle.net/21.15107/rcub_imagine_1650 .