TY  - JOUR
AU  - Lazić, Jelena
AU  - Spasić, Jelena
AU  - Francuski, Djordje
AU  - Tokić-Vujosević, Zorana
AU  - Nikodinović-Runić, Jasmina
AU  - Maslak, Veselin
AU  - Đokić, Lidija
PY  - 2016
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/929
AB  - Michael addition of aldehydes to nitro-olefins is an effective method to obtain useful chiral gamma-nitroaldehydes. gamma-Nitroaldehydes are precursors for chiral gamma-aminobutyric acid analogues, which have numerous pharmacological activities and are used for the treatment of neurological disorders. A whole-cell system based on recombinantly expressed 4-oxalocrotonate tautomerase (4-OT) was developed and shown to be an effective biocatalyst for the Michael addition of branched aldehydes to beta-nitrostyrenes. The aim of this study was to investigate the influence of the substitution of the N-terminal proline with lysine and arginine, both containing a reactive epsilon-amino group, on the Michael addition catalyzed by 4-OT. First, the effects of these mutations were examined by in silico analysis, followed by the generation of three terminal lysine mutants. The generated mutants, 4-OT_K, 4-OT_PK and 4-OT_KK were tested for their ability to utilise beta-nitrostyrene (1), (E)-1-nitro-2-(2-thienyl)ethene (2) and trans-p-chloro-beta-nitrostyrene (3) as Michael acceptors with isobutanal (2-methylpropanal) as the donor. For comparison, the lithium salt of lysine was used in the same organocatalytic reactions. In general, the introduction of lysine had a negative effect on Michael additions based on overall product yields. However, additional lysine residues at the N-terminus of the protein resulted in structural changes that enhanced the activity towards 2 and 3. Therefore, the N-terminal proline is important for 4-OT-catalysed Michael-additions, but it is not essential.
PB  - Srpsko hemijsko društvo, Beograd
T2  - Journal of the Serbian Chemical Society
T1  - Importance of N-terminal proline for the promiscuous activity of 4-oxalocrotonate tautomerase (4-OT)
EP  - 881
IS  - 8
SP  - 871
VL  - 81
DO  - 10.2298/JSC160222053L
ER  - 

@article{
author = "Lazić, Jelena and Spasić, Jelena and Francuski, Djordje and Tokić-Vujosević, Zorana and Nikodinović-Runić, Jasmina and Maslak, Veselin and Đokić, Lidija",
year = "2016",
abstract = "Michael addition of aldehydes to nitro-olefins is an effective method to obtain useful chiral gamma-nitroaldehydes. gamma-Nitroaldehydes are precursors for chiral gamma-aminobutyric acid analogues, which have numerous pharmacological activities and are used for the treatment of neurological disorders. A whole-cell system based on recombinantly expressed 4-oxalocrotonate tautomerase (4-OT) was developed and shown to be an effective biocatalyst for the Michael addition of branched aldehydes to beta-nitrostyrenes. The aim of this study was to investigate the influence of the substitution of the N-terminal proline with lysine and arginine, both containing a reactive epsilon-amino group, on the Michael addition catalyzed by 4-OT. First, the effects of these mutations were examined by in silico analysis, followed by the generation of three terminal lysine mutants. The generated mutants, 4-OT_K, 4-OT_PK and 4-OT_KK were tested for their ability to utilise beta-nitrostyrene (1), (E)-1-nitro-2-(2-thienyl)ethene (2) and trans-p-chloro-beta-nitrostyrene (3) as Michael acceptors with isobutanal (2-methylpropanal) as the donor. For comparison, the lithium salt of lysine was used in the same organocatalytic reactions. In general, the introduction of lysine had a negative effect on Michael additions based on overall product yields. However, additional lysine residues at the N-terminus of the protein resulted in structural changes that enhanced the activity towards 2 and 3. Therefore, the N-terminal proline is important for 4-OT-catalysed Michael-additions, but it is not essential.",
publisher = "Srpsko hemijsko društvo, Beograd",
journal = "Journal of the Serbian Chemical Society",
title = "Importance of N-terminal proline for the promiscuous activity of 4-oxalocrotonate tautomerase (4-OT)",
pages = "881-871",
number = "8",
volume = "81",
doi = "10.2298/JSC160222053L"
}

Lazić, J., Spasić, J., Francuski, D., Tokić-Vujosević, Z., Nikodinović-Runić, J., Maslak, V.,& Đokić, L.. (2016). Importance of N-terminal proline for the promiscuous activity of 4-oxalocrotonate tautomerase (4-OT). in Journal of the Serbian Chemical Society
Srpsko hemijsko društvo, Beograd., 81(8), 871-881.
https://doi.org/10.2298/JSC160222053L

Lazić J, Spasić J, Francuski D, Tokić-Vujosević Z, Nikodinović-Runić J, Maslak V, Đokić L. Importance of N-terminal proline for the promiscuous activity of 4-oxalocrotonate tautomerase (4-OT). in Journal of the Serbian Chemical Society. 2016;81(8):871-881.
doi:10.2298/JSC160222053L .

Lazić, Jelena, Spasić, Jelena, Francuski, Djordje, Tokić-Vujosević, Zorana, Nikodinović-Runić, Jasmina, Maslak, Veselin, Đokić, Lidija, "Importance of N-terminal proline for the promiscuous activity of 4-oxalocrotonate tautomerase (4-OT)" in Journal of the Serbian Chemical Society, 81, no. 8 (2016):871-881,
https://doi.org/10.2298/JSC160222053L . .

TY  - JOUR
AU  - Milovanović, Jelena
AU  - Minovska, Gordana
AU  - Šenerović, Lidija
AU  - O'Connor, Kevin
AU  - Jovanović, Predrag
AU  - Savić, Vladimir
AU  - Tokić-Vujosević, Zorana
AU  - Nikodinović-Runić, Jasmina
AU  - Maslak, Veselin
PY  - 2014
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/759
AB  - Synthesis of gamma-nitroaldehydes from branched chain aldehydes and a range of alpha,beta-unsaturated nitroalkenes was achieved by a whole-cell biocatalytic reaction using 4-oxalocrotonate tautomerase as catalyst. Under mild conditions, cyclic and acyclic branched aldehydes were converted into synthetically valuable quaternary carbon containing gamma-nitroaldehydes. The yields of the desired products were influenced by reaction condition parameters such as organic solvent, temperature and pH. The whole-cell biocatalytic approach to the generation of alpha,alpha-substituted gamma-nitroaldehydes was compared to the organocatalytic approach involving the lithium salt of phenylalanine as a catalyst. As the resulting gamma-nitroaldehydes exhibited moderate antifungal activity and mild in vitro cytotoxicity against human fibroblasts (0.2-0.4 mM) they could further be examined as potentially useful pharmaceutical synthons.
PB  - Royal Soc Chemistry, Cambridge
T2  - RSC Advances
T1  - Synthesis of gamma-nitroaldehydes containing quaternary carbon in the alpha-position using a 4-oxalocrotonate tautomerase whole-cell biocatalyst
EP  - 60510
IS  - 105
SP  - 60502
VL  - 4
DO  - 10.1039/c4ra05517a
ER  - 

@article{
author = "Milovanović, Jelena and Minovska, Gordana and Šenerović, Lidija and O'Connor, Kevin and Jovanović, Predrag and Savić, Vladimir and Tokić-Vujosević, Zorana and Nikodinović-Runić, Jasmina and Maslak, Veselin",
year = "2014",
abstract = "Synthesis of gamma-nitroaldehydes from branched chain aldehydes and a range of alpha,beta-unsaturated nitroalkenes was achieved by a whole-cell biocatalytic reaction using 4-oxalocrotonate tautomerase as catalyst. Under mild conditions, cyclic and acyclic branched aldehydes were converted into synthetically valuable quaternary carbon containing gamma-nitroaldehydes. The yields of the desired products were influenced by reaction condition parameters such as organic solvent, temperature and pH. The whole-cell biocatalytic approach to the generation of alpha,alpha-substituted gamma-nitroaldehydes was compared to the organocatalytic approach involving the lithium salt of phenylalanine as a catalyst. As the resulting gamma-nitroaldehydes exhibited moderate antifungal activity and mild in vitro cytotoxicity against human fibroblasts (0.2-0.4 mM) they could further be examined as potentially useful pharmaceutical synthons.",
publisher = "Royal Soc Chemistry, Cambridge",
journal = "RSC Advances",
title = "Synthesis of gamma-nitroaldehydes containing quaternary carbon in the alpha-position using a 4-oxalocrotonate tautomerase whole-cell biocatalyst",
pages = "60510-60502",
number = "105",
volume = "4",
doi = "10.1039/c4ra05517a"
}

Milovanović, J., Minovska, G., Šenerović, L., O'Connor, K., Jovanović, P., Savić, V., Tokić-Vujosević, Z., Nikodinović-Runić, J.,& Maslak, V.. (2014). Synthesis of gamma-nitroaldehydes containing quaternary carbon in the alpha-position using a 4-oxalocrotonate tautomerase whole-cell biocatalyst. in RSC Advances
Royal Soc Chemistry, Cambridge., 4(105), 60502-60510.
https://doi.org/10.1039/c4ra05517a

Milovanović J, Minovska G, Šenerović L, O'Connor K, Jovanović P, Savić V, Tokić-Vujosević Z, Nikodinović-Runić J, Maslak V. Synthesis of gamma-nitroaldehydes containing quaternary carbon in the alpha-position using a 4-oxalocrotonate tautomerase whole-cell biocatalyst. in RSC Advances. 2014;4(105):60502-60510.
doi:10.1039/c4ra05517a .

Milovanović, Jelena, Minovska, Gordana, Šenerović, Lidija, O'Connor, Kevin, Jovanović, Predrag, Savić, Vladimir, Tokić-Vujosević, Zorana, Nikodinović-Runić, Jasmina, Maslak, Veselin, "Synthesis of gamma-nitroaldehydes containing quaternary carbon in the alpha-position using a 4-oxalocrotonate tautomerase whole-cell biocatalyst" in RSC Advances, 4, no. 105 (2014):60502-60510,
https://doi.org/10.1039/c4ra05517a . .