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  - Milenković, Jelena
AU  - Hrenović, Jasna
AU  - Matijašević, Danka
AU  - Nikšić, Miomir
AU  - Rajić, Nevenka
PY  - 2017
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1002
AB  - Two types of zeolites-natural clinoptilolite (NZ) and synthetic zeolite A (A)-were enriched with approx. 0.25 mmol of Cu(II), Zn(II), or Ag(I) ions, and the obtained materials (M-Z) were tested against three different isolates of Escherichia coli. Two isolates were environmental isolates from waters in Serbia whereas the third one was DSM 498. Antibacterial activity was studied in different water media-nutrient-rich media (peptone water), water from Sava Lake, and commercially available spring water. The Ag-containing zeolites showed bactericidal activity in the nutrient-rich peptone water after 1 h of contact. Cu- and Zn-containing zeolites showed bactericidal activity in real water samples. Antibacterial activity of the M-Z decreases in all three examined water media in the following order: Ag-NZ ae Ag-A  gt  Cu-NZ ae Cu-A  gt  Zn-NZ  gt  gt  gt  Zn-A, suggesting that mainly the metal type and not the zeolite type have a role in the antibacterial activity. Leaching experiments showed small amounts of the leached Cu(II) and Zn(II) ions, indicating that the antibacterial activity is not due to the metal ions but should be attributed to the M-Z itself. However, leached amounts of Ag(I) from Ag-NZ and Ag-A in peptone water indicate that the released Ag(I) could be mainly responsible for the bactericidal effect of the Ag(I)-containing zeolites. Since no loss of cellular material was found, the antibacterial activity is not attributed to cytoplasmic membrane damage.
PB  - Springer Heidelberg, Heidelberg
T2  - Environmental Science and Pollution Research
T1  - Bactericidal activity of Cu-, Zn-, and Ag-containing zeolites toward Escherichia coli isolates
EP  - 20281
IS  - 25
SP  - 20273
VL  - 24
DO  - 10.1007/s11356-017-9643-8
ER  - 

@article{
author = "Milenković, Jelena and Hrenović, Jasna and Matijašević, Danka and Nikšić, Miomir and Rajić, Nevenka",
year = "2017",
abstract = "Two types of zeolites-natural clinoptilolite (NZ) and synthetic zeolite A (A)-were enriched with approx. 0.25 mmol of Cu(II), Zn(II), or Ag(I) ions, and the obtained materials (M-Z) were tested against three different isolates of Escherichia coli. Two isolates were environmental isolates from waters in Serbia whereas the third one was DSM 498. Antibacterial activity was studied in different water media-nutrient-rich media (peptone water), water from Sava Lake, and commercially available spring water. The Ag-containing zeolites showed bactericidal activity in the nutrient-rich peptone water after 1 h of contact. Cu- and Zn-containing zeolites showed bactericidal activity in real water samples. Antibacterial activity of the M-Z decreases in all three examined water media in the following order: Ag-NZ ae Ag-A  gt  Cu-NZ ae Cu-A  gt  Zn-NZ  gt  gt  gt  Zn-A, suggesting that mainly the metal type and not the zeolite type have a role in the antibacterial activity. Leaching experiments showed small amounts of the leached Cu(II) and Zn(II) ions, indicating that the antibacterial activity is not due to the metal ions but should be attributed to the M-Z itself. However, leached amounts of Ag(I) from Ag-NZ and Ag-A in peptone water indicate that the released Ag(I) could be mainly responsible for the bactericidal effect of the Ag(I)-containing zeolites. Since no loss of cellular material was found, the antibacterial activity is not attributed to cytoplasmic membrane damage.",
publisher = "Springer Heidelberg, Heidelberg",
journal = "Environmental Science and Pollution Research",
title = "Bactericidal activity of Cu-, Zn-, and Ag-containing zeolites toward Escherichia coli isolates",
pages = "20281-20273",
number = "25",
volume = "24",
doi = "10.1007/s11356-017-9643-8"
}

Milenković, J., Hrenović, J., Matijašević, D., Nikšić, M.,& Rajić, N.. (2017). Bactericidal activity of Cu-, Zn-, and Ag-containing zeolites toward Escherichia coli isolates. in Environmental Science and Pollution Research
Springer Heidelberg, Heidelberg., 24(25), 20273-20281.
https://doi.org/10.1007/s11356-017-9643-8

Milenković J, Hrenović J, Matijašević D, Nikšić M, Rajić N. Bactericidal activity of Cu-, Zn-, and Ag-containing zeolites toward Escherichia coli isolates. in Environmental Science and Pollution Research. 2017;24(25):20273-20281.
doi:10.1007/s11356-017-9643-8 .

Milenković, Jelena, Hrenović, Jasna, Matijašević, Danka, Nikšić, Miomir, Rajić, Nevenka, "Bactericidal activity of Cu-, Zn-, and Ag-containing zeolites toward Escherichia coli isolates" in Environmental Science and Pollution Research, 24, no. 25 (2017):20273-20281,
https://doi.org/10.1007/s11356-017-9643-8 . .