Malešević, Milka

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  • Malešević, Milka (12)

Author's Bibliography

A novel thermostable YtnP lactonase from Stenotrophomonas maltophilia inhibits Pseudomonas aeruginosa virulence in vitro and in vivo

Ćurčić, Jovana; Dinić, Miroslav; Novović, Katarina; Vasiljević, Zorica; Kojić, Milan; Jovčić, Branko; Malešević, Milka

(2024)

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  - http://intor.torlakinstitut.com/handle/123456789/864
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.
T2  - International 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.",
journal = "International 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, 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 . .

A novel YtnP lactonase reduces the expression of p. aeruginosa MMA83 quorum sensing andvirulence factors gene expression

Ćurčić, Jovana; Jakovljević, Stefan; Novović, Katarina; Vasiljević, Zorica; Kojić, Milan; Jovčić, Branko; Malešević, Milka

(Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade, 2023)

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
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 the
protocol. Quantitative reverse transcription-polymerase chain reaction (RT-qPCR), was used to analyze
the 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 endogenous
control 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. aeruginosa
MMA83 treated with YtnP lactonase were significantly downregulated. The RT -qPCR results show that
treatment with YtnP-lactonase decreased the relative mRNA levels of genes involved in the production
of 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_intor_803
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 the
protocol. Quantitative reverse transcription-polymerase chain reaction (RT-qPCR), was used to analyze
the 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 endogenous
control 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. aeruginosa
MMA83 treated with YtnP lactonase were significantly downregulated. The RT -qPCR results show that
treatment with YtnP-lactonase decreased the relative mRNA levels of genes involved in the production
of 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_intor_803"
}
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_intor_803
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_intor_803 .
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_intor_803 .

Influence of amino acid substitution on the antimicrobial activity of bacteriocin lactolisterin BU

Gardijan, Lazar; Kojić, Milan; Jovanović, Goran; Malešević, Milka

(Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade, 2023)

TY  - CONF
AU  - Gardijan, Lazar
AU  - Kojić, Milan
AU  - Jovanović, Goran
AU  - Malešević, Milka
PY  - 2023
UR  - http://intor.torlakinstitut.com/handle/123456789/804
AB  - Introduction: Lactolisterin BU (LBU) is a potent bacteriocin derived from Lactococcuslactis subsp. lactis
bv. diacetylactis BGBU1-4. It exhibits antimicrobial properties against Gram-positive food spoilage and
foodborne pathogens. This research aimed to explore the impact of amino acid substitution in LBU on
its antimicrobial activity by utilizing in silico prediction of LBU’ssecondary structure and amino acid substitutions.
Methods: The secondary structure of LBU was predicted using Phyre2 software. Five variants of LBU
were selected and chemically synthesized, along with unaltered LBU and BHT-B,serving as controls. Peptides were twofold diluted in distilled water, resulting in final concentrations ranging from 1000 µg/ml
to 0.5 µg/ml. An agarspot test, employing 5 µl of the dilution, was conducted on three indicatorstrains:
Lactococcus lactis BGMN1-596, Listeria monocytogenes ATCC19111, and Staphylococcus aureus
ATCC25923. The presence of inhibition zones was analyzed after overnight incubation at 37°C (S. aureus)
and 30°C (L. lactis and L. monocytogenes).
Results: Phyre2 analysis unveiled the presence of two α-helices in LBU’s structure. The majority of LBU
variants displayed altered antimicrobial activity, with some changes being genusspecific, potentially attributable to variances in cell wall composition. Some variants completely lost their activity, underscoring the significance of native amino acids or their physicochemical properties in the corresponding
positions within LBU’s structure. Furthermore, it was confirmed that chemically synthesized LBU effectively retains its antimicrobial activity.
Conclusion: Changesin amino acid composition give insight on structure-function relationship of LBU.
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  - Influence of amino acid substitution on the antimicrobial activity of bacteriocin lactolisterin BU
EP  - 123
SP  - 123
UR  - https://hdl.handle.net/21.15107/rcub_intor_804
ER  - 
@conference{
author = "Gardijan, Lazar and Kojić, Milan and Jovanović, Goran and Malešević, Milka",
year = "2023",
abstract = "Introduction: Lactolisterin BU (LBU) is a potent bacteriocin derived from Lactococcuslactis subsp. lactis
bv. diacetylactis BGBU1-4. It exhibits antimicrobial properties against Gram-positive food spoilage and
foodborne pathogens. This research aimed to explore the impact of amino acid substitution in LBU on
its antimicrobial activity by utilizing in silico prediction of LBU’ssecondary structure and amino acid substitutions.
Methods: The secondary structure of LBU was predicted using Phyre2 software. Five variants of LBU
were selected and chemically synthesized, along with unaltered LBU and BHT-B,serving as controls. Peptides were twofold diluted in distilled water, resulting in final concentrations ranging from 1000 µg/ml
to 0.5 µg/ml. An agarspot test, employing 5 µl of the dilution, was conducted on three indicatorstrains:
Lactococcus lactis BGMN1-596, Listeria monocytogenes ATCC19111, and Staphylococcus aureus
ATCC25923. The presence of inhibition zones was analyzed after overnight incubation at 37°C (S. aureus)
and 30°C (L. lactis and L. monocytogenes).
Results: Phyre2 analysis unveiled the presence of two α-helices in LBU’s structure. The majority of LBU
variants displayed altered antimicrobial activity, with some changes being genusspecific, potentially attributable to variances in cell wall composition. Some variants completely lost their activity, underscoring the significance of native amino acids or their physicochemical properties in the corresponding
positions within LBU’s structure. Furthermore, it was confirmed that chemically synthesized LBU effectively retains its antimicrobial activity.
Conclusion: Changesin amino acid composition give insight on structure-function relationship of LBU.",
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 = "Influence of amino acid substitution on the antimicrobial activity of bacteriocin lactolisterin BU",
pages = "123-123",
url = "https://hdl.handle.net/21.15107/rcub_intor_804"
}
Gardijan, L., Kojić, M., Jovanović, G.,& Malešević, M.. (2023). Influence of amino acid substitution on the antimicrobial activity of bacteriocin lactolisterin BU. 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., 123-123.
https://hdl.handle.net/21.15107/rcub_intor_804
Gardijan L, Kojić M, Jovanović G, Malešević M. Influence of amino acid substitution on the antimicrobial activity of bacteriocin lactolisterin BU. 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;:123-123.
https://hdl.handle.net/21.15107/rcub_intor_804 .
Gardijan, Lazar, Kojić, Milan, Jovanović, Goran, Malešević, Milka, "Influence of amino acid substitution on the antimicrobial activity of bacteriocin lactolisterin BU" 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):123-123,
https://hdl.handle.net/21.15107/rcub_intor_804 .

Short-term effect of Brevibacillus laterosporus supplemented diet on worker honey bee microbiome

Malešević, Milka; Stanisavljević, Nemanja; Rašić, Slađan; Vukotić, Goran; Gardijan, Lazar; Obradović, Mina; Kojić, Milan

(Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade, 2023)

TY  - CONF
AU  - Malešević, Milka
AU  - Stanisavljević, Nemanja
AU  - Rašić, Slađan
AU  - Vukotić, Goran
AU  - Gardijan, Lazar
AU  - Obradović, Mina
AU  - Kojić, Milan
PY  - 2023
UR  - http://intor.torlakinstitut.com/handle/123456789/823
AB  - Introduction: Brevibacillus laterosporus is a promising microbiological agent that can be used to prevent and control destructive diseases affecting honey bee colonies. In the presentstudy, the short-termeffect of the B. laterosporus BGSP11 bee diet on microbiota and mycobiota was investigated.Methods: The honey bee diet was supplemented with spores of B. laterosporus BGSP11 at a concentration of 1×108 CFU/mL in sucrose solution. Metabarcoding analysis of the bee microbial community profile was performed based on 16S RNA (bacteriobiota) and Internally Transcribes Spacer (ITS) region(mycobiota) obtained using MiSeq Illumina sequencing. The QIIME2 v2021.4 pipeline was used to analyze the obtained amplicon data library.Results: The results show that the BGSP11 bee diet slightly altered the bee microbiota and did not leadto potentially harmful changes in the bacterial microbiota. Moreover, it can potentially induce positivechanges, mainly reflected in the reduction of opportunistic bacteria. On the other hand, the treatmenthad a greater effect on mycobiota. However, the changesin the bee mycobiome caused by the treatmentcannot be considered a priori as beneficial or harmful,since the interaction between the bee and its mycobiome is not sufficiently studied. The observed positive changes in the bee mycobiome are mainlyreflected in the reduction of phytopathogenic fungi that may affect the organoleptic and techno-functional properties of honey.Conclusion: This pilot study suggests that the introduction of BGSP11 in beekeeping practice as a biological agent could be considered due to no harmful effects observed on the microbiota of bees.
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  - Short-term effect of Brevibacillus laterosporus supplemented diet on worker honey bee microbiome
EP  - 112
SP  - 112
UR  - https://hdl.handle.net/21.15107/rcub_intor_823
ER  - 
@conference{
author = "Malešević, Milka and Stanisavljević, Nemanja and Rašić, Slađan and Vukotić, Goran and Gardijan, Lazar and Obradović, Mina and Kojić, Milan",
year = "2023",
abstract = "Introduction: Brevibacillus laterosporus is a promising microbiological agent that can be used to prevent and control destructive diseases affecting honey bee colonies. In the presentstudy, the short-termeffect of the B. laterosporus BGSP11 bee diet on microbiota and mycobiota was investigated.Methods: The honey bee diet was supplemented with spores of B. laterosporus BGSP11 at a concentration of 1×108 CFU/mL in sucrose solution. Metabarcoding analysis of the bee microbial community profile was performed based on 16S RNA (bacteriobiota) and Internally Transcribes Spacer (ITS) region(mycobiota) obtained using MiSeq Illumina sequencing. The QIIME2 v2021.4 pipeline was used to analyze the obtained amplicon data library.Results: The results show that the BGSP11 bee diet slightly altered the bee microbiota and did not leadto potentially harmful changes in the bacterial microbiota. Moreover, it can potentially induce positivechanges, mainly reflected in the reduction of opportunistic bacteria. On the other hand, the treatmenthad a greater effect on mycobiota. However, the changesin the bee mycobiome caused by the treatmentcannot be considered a priori as beneficial or harmful,since the interaction between the bee and its mycobiome is not sufficiently studied. The observed positive changes in the bee mycobiome are mainlyreflected in the reduction of phytopathogenic fungi that may affect the organoleptic and techno-functional properties of honey.Conclusion: This pilot study suggests that the introduction of BGSP11 in beekeeping practice as a biological agent could be considered due to no harmful effects observed on the microbiota of bees.",
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 = "Short-term effect of Brevibacillus laterosporus supplemented diet on worker honey bee microbiome",
pages = "112-112",
url = "https://hdl.handle.net/21.15107/rcub_intor_823"
}
Malešević, M., Stanisavljević, N., Rašić, S., Vukotić, G., Gardijan, L., Obradović, M.,& Kojić, M.. (2023). Short-term effect of Brevibacillus laterosporus supplemented diet on worker honey bee microbiome. 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., 112-112.
https://hdl.handle.net/21.15107/rcub_intor_823
Malešević M, Stanisavljević N, Rašić S, Vukotić G, Gardijan L, Obradović M, Kojić M. Short-term effect of Brevibacillus laterosporus supplemented diet on worker honey bee microbiome. 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;:112-112.
https://hdl.handle.net/21.15107/rcub_intor_823 .
Malešević, Milka, Stanisavljević, Nemanja, Rašić, Slađan, Vukotić, Goran, Gardijan, Lazar, Obradović, Mina, Kojić, Milan, "Short-term effect of Brevibacillus laterosporus supplemented diet on worker honey bee microbiome" 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):112-112,
https://hdl.handle.net/21.15107/rcub_intor_823 .

Exploring the antibacterial potential of Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 by genome mining, bacteriocin gene overexpression, and chemical protein synthesis of lactolisterin BU variants

Malešević, Milka; Gardijan, Lazar; Miljković, Marija; O'Connor, Paula M; Mirković, Nemanja; Jovčić, Branko; Cotter, Paul D; Jovanovic, Goran; Kojić, Milan

(2023)

TY  - JOUR
AU  - Malešević, Milka
AU  - Gardijan, Lazar
AU  - Miljković, Marija
AU  - O'Connor, Paula M
AU  - Mirković, Nemanja
AU  - Jovčić, Branko
AU  - Cotter, Paul D
AU  - Jovanovic, Goran
AU  - Kojić, Milan
PY  - 2023
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1828
UR  - http://intor.torlakinstitut.com/handle/123456789/740
AB  - Lactic acid bacterium Lactococcus lactis BGBU1-4 produces 43 amino acids (aa) long bacteriocin, lactolisterin BU (LBU), a 5.161 kDa peptide with potent antibacterial activity against many Gram-positive pathogens. In addition, BGBU1-4 produces an additional unknown product of 3.642 kDa with antibacterial activity. Here, we determined that the significant amount of naturally produced LBU breaks down to create a 3.642 kDa truncated form of LBU bacteriocin consisting of 31 N-terminal aa (LBU1-31) that exhibits 12.5% the antibacterial activity of the full-length LBU. We showed that chemically synthesized LBU is stable and 50% less active than native LBU, and so we used the synthetic peptides of LBU and its variants to further study their activities and antibacterial potential. Deletion analysis of LBU revealed that the 24 N-terminal aa of LBU (LBU1-24) are responsible for antibacterial activity, while downstream aa (25–43) determine the species-specific effectiveness of LBU. Although LBU1-31 contains aa 1–24, the truncation at position 31 is predicted to change the structure within aa 15–31 and might impact on antibacterial activity. Intriguingly, whole genome sequencing and genome mining established that BGBU1-4 is abundant in genes that encode potential antibacterials, but produces LBU and its breakdown product LBU1-31 exclusively.
T2  - Letters in Applied Microbiology
T2  - Letters in Applied MicrobiologyLetters in Applied Microbiology
T1  - Exploring the antibacterial potential of Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 by genome mining, bacteriocin gene overexpression, and chemical protein synthesis of lactolisterin BU variants
IS  - 2
SP  - ovad004
VL  - 76
DO  - 10.1093/lambio/ovad004
ER  - 
@article{
author = "Malešević, Milka and Gardijan, Lazar and Miljković, Marija and O'Connor, Paula M and Mirković, Nemanja and Jovčić, Branko and Cotter, Paul D and Jovanovic, Goran and Kojić, Milan",
year = "2023",
abstract = "Lactic acid bacterium Lactococcus lactis BGBU1-4 produces 43 amino acids (aa) long bacteriocin, lactolisterin BU (LBU), a 5.161 kDa peptide with potent antibacterial activity against many Gram-positive pathogens. In addition, BGBU1-4 produces an additional unknown product of 3.642 kDa with antibacterial activity. Here, we determined that the significant amount of naturally produced LBU breaks down to create a 3.642 kDa truncated form of LBU bacteriocin consisting of 31 N-terminal aa (LBU1-31) that exhibits 12.5% the antibacterial activity of the full-length LBU. We showed that chemically synthesized LBU is stable and 50% less active than native LBU, and so we used the synthetic peptides of LBU and its variants to further study their activities and antibacterial potential. Deletion analysis of LBU revealed that the 24 N-terminal aa of LBU (LBU1-24) are responsible for antibacterial activity, while downstream aa (25–43) determine the species-specific effectiveness of LBU. Although LBU1-31 contains aa 1–24, the truncation at position 31 is predicted to change the structure within aa 15–31 and might impact on antibacterial activity. Intriguingly, whole genome sequencing and genome mining established that BGBU1-4 is abundant in genes that encode potential antibacterials, but produces LBU and its breakdown product LBU1-31 exclusively.",
journal = "Letters in Applied Microbiology, Letters in Applied MicrobiologyLetters in Applied Microbiology",
title = "Exploring the antibacterial potential of Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 by genome mining, bacteriocin gene overexpression, and chemical protein synthesis of lactolisterin BU variants",
number = "2",
pages = "ovad004",
volume = "76",
doi = "10.1093/lambio/ovad004"
}
Malešević, M., Gardijan, L., Miljković, M., O'Connor, P. M., Mirković, N., Jovčić, B., Cotter, P. D., Jovanovic, G.,& Kojić, M.. (2023). Exploring the antibacterial potential of Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 by genome mining, bacteriocin gene overexpression, and chemical protein synthesis of lactolisterin BU variants. in Letters in Applied Microbiology, 76(2), ovad004.
https://doi.org/10.1093/lambio/ovad004
Malešević M, Gardijan L, Miljković M, O'Connor PM, Mirković N, Jovčić B, Cotter PD, Jovanovic G, Kojić M. Exploring the antibacterial potential of Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 by genome mining, bacteriocin gene overexpression, and chemical protein synthesis of lactolisterin BU variants. in Letters in Applied Microbiology. 2023;76(2):ovad004.
doi:10.1093/lambio/ovad004 .
Malešević, Milka, Gardijan, Lazar, Miljković, Marija, O'Connor, Paula M, Mirković, Nemanja, Jovčić, Branko, Cotter, Paul D, Jovanovic, Goran, Kojić, Milan, "Exploring the antibacterial potential of Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 by genome mining, bacteriocin gene overexpression, and chemical protein synthesis of lactolisterin BU variants" in Letters in Applied Microbiology, 76, no. 2 (2023):ovad004,
https://doi.org/10.1093/lambio/ovad004 . .
1
2
2

Comparative genomics of trimethoprim-sulfamethoxazole-resistant Achromobacter xylosoxidans clinical isolates from Serbia reveals shortened variant of class 1 integron integrase gene

Filipić, Brankica; Malešević, Milka; Vasiljević, Zorica; Novović, Katarina; Kojić, Milan; Jovčić, Branko

(Springer Science and Business Media B.V., 2022)

TY  - JOUR
AU  - Filipić, Brankica
AU  - Malešević, Milka
AU  - Vasiljević, Zorica
AU  - Novović, Katarina
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2022
UR  - http://intor.torlakinstitut.com/handle/123456789/724
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 . .
2
2
1

Brevibacillus laterosporus supplementation diet modulates honey bee microbiome

Malešević, Milka; Rašić, Slađan; Santra, Violeta; Kojić, Milan; Stanisavljević, Nemanja

(Novi Sad : Faculty of Sciences, Department of Biology and Ecology, 2021)

TY  - CONF
AU  - Malešević, Milka
AU  - Rašić, Slađan
AU  - Santra, Violeta
AU  - Kojić, Milan
AU  - Stanisavljević, Nemanja
PY  - 2021
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1871
UR  - http://intor.torlakinstitut.com/handle/123456789/703
AB  - Among them, bacterial and fungal pathogens Paenibacillus larvae, Melissococcus pluton, Ascosphera apis andNosema ceranae play a major impact on honey bees colonies. Thus, developing alternative prophylactic andcurative strategies are urgently needed. The use of probiotic bacteria in honey bee supplemental feeding istherefore promising to treat or prevent diseases. Brevibacillus laterosporus, Gram-positive endospore formingbacilli, is recognised as one of the promising antibacterial and antifungal agents producer.The aim of this study was to examine the short-therm effects of B. laterosporus supplemented diet on workerhoney bee microbiome.Dry spores of B. laterosporus strain BGSP11 have been administrated through a sugar syrup diet to tencolonies and a representative specimen of worker honey bees was taken before the start of the treatmentand immediately after the syrup was consumed. The microbial diversity was assessed before and after thetreatment using Illumina MiSeq sequencing platforms (ID Genomics service, Seattle, WA, USA). 16s rRNAsequencing for bacterial community profiling and fungal Internally Transcribes Spacer for mycological taxaprofiling were used. The next-generation microbiome bioinformatics platform QIIME2 v 2021.4 was used forfiltering and denoising obtained sequences, calculation of diversity metrics and taxonomy assignment. Thefeature classifier was trained using the Greengenes v 13_8 for bacterial taxa and fungal UNITE database v 8.3.The results obtained in this study indicated statisticaly significant alfa diversity between control and experimentalgroup honey bee microbiota composition. The diversity abundance was higher in control comparingto the group treated with B. laterosporus strain BGSP11 spores. There was no significant diference in Bray-Curtis distance among two groups of analysed samples. Regarding to mycological abundance, compositionwas completely different between two groups; control group had Claviceps as predominant genus, while intreated group of honey bee microbiome Metschnikowia genus was prevalent, indicating that the presence offungal pathogens in treated group is highly diminished.
PB  - Novi Sad : Faculty of Sciences, Department of Biology and Ecology
C3  - Biologia Serbica
T1  - Brevibacillus laterosporus supplementation diet modulates honey bee microbiome
IS  - 1 (Special Edition)
SP  - 113
VL  - 43
UR  - https://hdl.handle.net/21.15107/rcub_intor_703
ER  - 
@conference{
author = "Malešević, Milka and Rašić, Slađan and Santra, Violeta and Kojić, Milan and Stanisavljević, Nemanja",
year = "2021",
abstract = "Among them, bacterial and fungal pathogens Paenibacillus larvae, Melissococcus pluton, Ascosphera apis andNosema ceranae play a major impact on honey bees colonies. Thus, developing alternative prophylactic andcurative strategies are urgently needed. The use of probiotic bacteria in honey bee supplemental feeding istherefore promising to treat or prevent diseases. Brevibacillus laterosporus, Gram-positive endospore formingbacilli, is recognised as one of the promising antibacterial and antifungal agents producer.The aim of this study was to examine the short-therm effects of B. laterosporus supplemented diet on workerhoney bee microbiome.Dry spores of B. laterosporus strain BGSP11 have been administrated through a sugar syrup diet to tencolonies and a representative specimen of worker honey bees was taken before the start of the treatmentand immediately after the syrup was consumed. The microbial diversity was assessed before and after thetreatment using Illumina MiSeq sequencing platforms (ID Genomics service, Seattle, WA, USA). 16s rRNAsequencing for bacterial community profiling and fungal Internally Transcribes Spacer for mycological taxaprofiling were used. The next-generation microbiome bioinformatics platform QIIME2 v 2021.4 was used forfiltering and denoising obtained sequences, calculation of diversity metrics and taxonomy assignment. Thefeature classifier was trained using the Greengenes v 13_8 for bacterial taxa and fungal UNITE database v 8.3.The results obtained in this study indicated statisticaly significant alfa diversity between control and experimentalgroup honey bee microbiota composition. The diversity abundance was higher in control comparingto the group treated with B. laterosporus strain BGSP11 spores. There was no significant diference in Bray-Curtis distance among two groups of analysed samples. Regarding to mycological abundance, compositionwas completely different between two groups; control group had Claviceps as predominant genus, while intreated group of honey bee microbiome Metschnikowia genus was prevalent, indicating that the presence offungal pathogens in treated group is highly diminished.",
publisher = "Novi Sad : Faculty of Sciences, Department of Biology and Ecology",
journal = "Biologia Serbica",
title = "Brevibacillus laterosporus supplementation diet modulates honey bee microbiome",
number = "1 (Special Edition)",
pages = "113",
volume = "43",
url = "https://hdl.handle.net/21.15107/rcub_intor_703"
}
Malešević, M., Rašić, S., Santra, V., Kojić, M.,& Stanisavljević, N.. (2021). Brevibacillus laterosporus supplementation diet modulates honey bee microbiome. in Biologia Serbica
Novi Sad : Faculty of Sciences, Department of Biology and Ecology., 43(1 (Special Edition)), 113.
https://hdl.handle.net/21.15107/rcub_intor_703
Malešević M, Rašić S, Santra V, Kojić M, Stanisavljević N. Brevibacillus laterosporus supplementation diet modulates honey bee microbiome. in Biologia Serbica. 2021;43(1 (Special Edition)):113.
https://hdl.handle.net/21.15107/rcub_intor_703 .
Malešević, Milka, Rašić, Slađan, Santra, Violeta, Kojić, Milan, Stanisavljević, Nemanja, "Brevibacillus laterosporus supplementation diet modulates honey bee microbiome" in Biologia Serbica, 43, no. 1 (Special Edition) (2021):113,
https://hdl.handle.net/21.15107/rcub_intor_703 .

Burkholderia cepacia YtnP and Y2-aiiA lactonases inhibit virulence of Pseudomonas aeruginosa via quorum quenching activity

Malešević, Milka; Stanisavljević, Nemanja; Novović, Katarina; Polović, Natalija; Vasiljević, Zorica; Kojić, Milan; Jovčić, Branko

(Academic Press Ltd- Elsevier Science Ltd, London, 2020)

TY  - JOUR
AU  - Malešević, Milka
AU  - Stanisavljević, Nemanja
AU  - Novović, Katarina
AU  - Polović, Natalija
AU  - Vasiljević, Zorica
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2020
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1338
UR  - http://intor.torlakinstitut.com/handle/123456789/705
AB  - Burkholderia cepacia is well known as the causative agent of infections in humans where often shares niche with other pathogens, like Pseudomonas aeruginosa. Clinical isolate Burkholderia sp. BCC4135 was selected due to its strong quorum quenching (QQ) activity. Whole genome sequencing unveiled this isolate as B. cepacia with unique sequence type ST1485 and a myriad of genes belonging to resistome and virulome. Two QQ lactonases YtnP and Y2-aiiA originated from B. cepacia BCC4135 were cloned, expressed, and functionally characterized. They were active against a broad substrate spectrum of the N-acyl-homoserine lactones (AHLs). The YtnP lactonase was inactive, while Y2-aiiA was active against N-tetradecanoyl-DL-homoserine lactone (C14-HSL) which could imply the difference in their biological roles from the aspect of its quorum sensing (QS) autoregulation and interference with the QS systems of bacteria residing within the same niche. Both YtnP and Y2-aiiA were able to attenuate virulence potential of P. aeruginosa MMA83 clinical isolate declining its biofilm formation and virulence factors production. B. cepacia BCC4135 lactonases interfered with the las, rhl, and even pqs QS circuit of P. aeruginosa MMA83 transcription and the effect of combined enzymes was even more prominent. B. cepacia BCC4135 also employs the CepI/R QS system for governing its own virulence traits and possibly self-regulates the QQ/QS network through the different expression and activity of YtnP and/or Y2-aiiA. Our findings pointed out that BCC4135 lactonases could be exploited as an effective antivirulence drugs against P. aeruginosa and gave us a new insight into B. cepacia QQ/QS machinery.
PB  - Academic Press Ltd- Elsevier Science Ltd, London
T2  - Microbial Pathogenesis
T1  - Burkholderia cepacia YtnP and Y2-aiiA lactonases inhibit virulence of Pseudomonas aeruginosa via quorum quenching activity
VL  - 149
DO  - 10.1016/j.micpath.2020.104561
ER  - 
@article{
author = "Malešević, Milka and Stanisavljević, Nemanja and Novović, Katarina and Polović, Natalija and Vasiljević, Zorica and Kojić, Milan and Jovčić, Branko",
year = "2020",
abstract = "Burkholderia cepacia is well known as the causative agent of infections in humans where often shares niche with other pathogens, like Pseudomonas aeruginosa. Clinical isolate Burkholderia sp. BCC4135 was selected due to its strong quorum quenching (QQ) activity. Whole genome sequencing unveiled this isolate as B. cepacia with unique sequence type ST1485 and a myriad of genes belonging to resistome and virulome. Two QQ lactonases YtnP and Y2-aiiA originated from B. cepacia BCC4135 were cloned, expressed, and functionally characterized. They were active against a broad substrate spectrum of the N-acyl-homoserine lactones (AHLs). The YtnP lactonase was inactive, while Y2-aiiA was active against N-tetradecanoyl-DL-homoserine lactone (C14-HSL) which could imply the difference in their biological roles from the aspect of its quorum sensing (QS) autoregulation and interference with the QS systems of bacteria residing within the same niche. Both YtnP and Y2-aiiA were able to attenuate virulence potential of P. aeruginosa MMA83 clinical isolate declining its biofilm formation and virulence factors production. B. cepacia BCC4135 lactonases interfered with the las, rhl, and even pqs QS circuit of P. aeruginosa MMA83 transcription and the effect of combined enzymes was even more prominent. B. cepacia BCC4135 also employs the CepI/R QS system for governing its own virulence traits and possibly self-regulates the QQ/QS network through the different expression and activity of YtnP and/or Y2-aiiA. Our findings pointed out that BCC4135 lactonases could be exploited as an effective antivirulence drugs against P. aeruginosa and gave us a new insight into B. cepacia QQ/QS machinery.",
publisher = "Academic Press Ltd- Elsevier Science Ltd, London",
journal = "Microbial Pathogenesis",
title = "Burkholderia cepacia YtnP and Y2-aiiA lactonases inhibit virulence of Pseudomonas aeruginosa via quorum quenching activity",
volume = "149",
doi = "10.1016/j.micpath.2020.104561"
}
Malešević, M., Stanisavljević, N., Novović, K., Polović, N., Vasiljević, Z., Kojić, M.,& Jovčić, B.. (2020). Burkholderia cepacia YtnP and Y2-aiiA lactonases inhibit virulence of Pseudomonas aeruginosa via quorum quenching activity. in Microbial Pathogenesis
Academic Press Ltd- Elsevier Science Ltd, London., 149.
https://doi.org/10.1016/j.micpath.2020.104561
Malešević M, Stanisavljević N, Novović K, Polović N, Vasiljević Z, Kojić M, Jovčić B. Burkholderia cepacia YtnP and Y2-aiiA lactonases inhibit virulence of Pseudomonas aeruginosa via quorum quenching activity. in Microbial Pathogenesis. 2020;149.
doi:10.1016/j.micpath.2020.104561 .
Malešević, Milka, Stanisavljević, Nemanja, Novović, Katarina, Polović, Natalija, Vasiljević, Zorica, Kojić, Milan, Jovčić, Branko, "Burkholderia cepacia YtnP and Y2-aiiA lactonases inhibit virulence of Pseudomonas aeruginosa via quorum quenching activity" in Microbial Pathogenesis, 149 (2020),
https://doi.org/10.1016/j.micpath.2020.104561 . .
1
14
3
14

Fluoroquinolone-resistant Achromobacter xylosoxidans clinical isolates from Serbia: high prevalence of the aac-(6)-Ib-cr gene among resistant isolates

Lilić, Branislav; Filipić, Brankica; Malešević, Milka; Novović, Katarina; Vasiljević, Zorica; Kojić, Milan; Jovčić, Branko

(Springer, Dordrecht, 2019)

TY  - JOUR
AU  - Lilić, Branislav
AU  - Filipić, Brankica
AU  - Malešević, Milka
AU  - Novović, Katarina
AU  - Vasiljević, Zorica
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2019
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1278
UR  - http://intor.torlakinstitut.com/handle/123456789/742
AB  - The aim of this study was to evaluate the contribution of plasmid-mediated genes and efflux to fluoroquinolone resistance in collection of Achromobacter spp. gathered during a 3-year period. Susceptibility to ciprofloxacin and levofloxacin was tested by disk diffusion and microdilution tests for a collection of 98 Achromobacter spp. clinical isolates. Identification of fluoroquinolone-resistant isolates was performed by sequencing and phylogenetic analyses of the nrdA gene. Genetic relatedness among resistant isolates was determined by pulsed-field gel electrophoresis (PFGE) analysis. The influence of an H+ conductor cyanide m-chlorophenyl hydrazone (CCCP) and a resistance-nodulation-division-type efflux pump inhibitor phenylalanine-arginine beta-naphthylamide (PAN) on minimal inhibitory concentration (MIC) value was evaluated by broth microdilution. The presence of the plasmid-mediated qnrA, qnrB, qnrC, qnrS, and aac-(6)-Ib-cr genes was investigated by PCR and sequencing. Achromobacter spp. isolates that were resistant or intermediately resistant to fluoroquinolones in disk diffusion tests (44/98) were subjected to microdilution. As a result, 20/98 isolates were confirmed to be resistant to ciprofloxacin while 10/98 was resistant to levofloxacin. CCCP decreased twofold MIC value for ciprofloxacin in six isolates and more than 16 times in one isolate, while MIC value for levofloxacin was decreased in all isolates (twofold to more than eightfold). Fluoroquinolone-resistant isolates were identified as A. xylosoxidans with the nrdA gene sequencing. PFGE revealed that resistant isolates belonged to seven different genotypes. Ten isolates belonging to four genotypes were positive for the aac-(6)-Ib-cr gene. Although resistance to fluoroquinolones was not widespread among analyzed isolates, detected contribution of efflux pumps and the presence of the aac-(6)-Ib-cr gene present a platform for emergence of more resistant strains.
PB  - Springer, Dordrecht
T2  - Folia Microbiologica
T1  - Fluoroquinolone-resistant Achromobacter xylosoxidans clinical isolates from Serbia: high prevalence of the aac-(6)-Ib-cr gene among resistant isolates
EP  - 159
IS  - 2
SP  - 153
VL  - 64
DO  - 10.1007/s12223-018-0639-7
ER  - 
@article{
author = "Lilić, Branislav and Filipić, Brankica and Malešević, Milka and Novović, Katarina and Vasiljević, Zorica and Kojić, Milan and Jovčić, Branko",
year = "2019",
abstract = "The aim of this study was to evaluate the contribution of plasmid-mediated genes and efflux to fluoroquinolone resistance in collection of Achromobacter spp. gathered during a 3-year period. Susceptibility to ciprofloxacin and levofloxacin was tested by disk diffusion and microdilution tests for a collection of 98 Achromobacter spp. clinical isolates. Identification of fluoroquinolone-resistant isolates was performed by sequencing and phylogenetic analyses of the nrdA gene. Genetic relatedness among resistant isolates was determined by pulsed-field gel electrophoresis (PFGE) analysis. The influence of an H+ conductor cyanide m-chlorophenyl hydrazone (CCCP) and a resistance-nodulation-division-type efflux pump inhibitor phenylalanine-arginine beta-naphthylamide (PAN) on minimal inhibitory concentration (MIC) value was evaluated by broth microdilution. The presence of the plasmid-mediated qnrA, qnrB, qnrC, qnrS, and aac-(6)-Ib-cr genes was investigated by PCR and sequencing. Achromobacter spp. isolates that were resistant or intermediately resistant to fluoroquinolones in disk diffusion tests (44/98) were subjected to microdilution. As a result, 20/98 isolates were confirmed to be resistant to ciprofloxacin while 10/98 was resistant to levofloxacin. CCCP decreased twofold MIC value for ciprofloxacin in six isolates and more than 16 times in one isolate, while MIC value for levofloxacin was decreased in all isolates (twofold to more than eightfold). Fluoroquinolone-resistant isolates were identified as A. xylosoxidans with the nrdA gene sequencing. PFGE revealed that resistant isolates belonged to seven different genotypes. Ten isolates belonging to four genotypes were positive for the aac-(6)-Ib-cr gene. Although resistance to fluoroquinolones was not widespread among analyzed isolates, detected contribution of efflux pumps and the presence of the aac-(6)-Ib-cr gene present a platform for emergence of more resistant strains.",
publisher = "Springer, Dordrecht",
journal = "Folia Microbiologica",
title = "Fluoroquinolone-resistant Achromobacter xylosoxidans clinical isolates from Serbia: high prevalence of the aac-(6)-Ib-cr gene among resistant isolates",
pages = "159-153",
number = "2",
volume = "64",
doi = "10.1007/s12223-018-0639-7"
}
Lilić, B., Filipić, B., Malešević, M., Novović, K., Vasiljević, Z., Kojić, M.,& Jovčić, B.. (2019). Fluoroquinolone-resistant Achromobacter xylosoxidans clinical isolates from Serbia: high prevalence of the aac-(6)-Ib-cr gene among resistant isolates. in Folia Microbiologica
Springer, Dordrecht., 64(2), 153-159.
https://doi.org/10.1007/s12223-018-0639-7
Lilić B, Filipić B, Malešević M, Novović K, Vasiljević Z, Kojić M, Jovčić B. Fluoroquinolone-resistant Achromobacter xylosoxidans clinical isolates from Serbia: high prevalence of the aac-(6)-Ib-cr gene among resistant isolates. in Folia Microbiologica. 2019;64(2):153-159.
doi:10.1007/s12223-018-0639-7 .
Lilić, Branislav, Filipić, Brankica, Malešević, Milka, Novović, Katarina, Vasiljević, Zorica, Kojić, Milan, Jovčić, Branko, "Fluoroquinolone-resistant Achromobacter xylosoxidans clinical isolates from Serbia: high prevalence of the aac-(6)-Ib-cr gene among resistant isolates" in Folia Microbiologica, 64, no. 2 (2019):153-159,
https://doi.org/10.1007/s12223-018-0639-7 . .
1
2
2
3

Bacterial Diversity among the Sediments of Glacial Lakes in the Western Balkans: Exploring the Impact of Human Population

Malešević, Milka; Mirković, Nemanja; Lozo, Jelena; Novović, Katarina; Filipić, Brankica; Kojić, Milan; Jovčić, Branko

(Taylor & Francis, 2019)

TY  - JOUR
AU  - Malešević, Milka
AU  - Mirković, Nemanja
AU  - Lozo, Jelena
AU  - Novović, Katarina
AU  - Filipić, Brankica
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2019
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1297
UR  - http://intor.torlakinstitut.com/handle/123456789/696
AB  - 16S rRNA gene-based metagenomic approach was used to assess the biodiversity of bacterial communities in the sediments of selected glacial lakes in the Western Balkans and to assess the impact of human population on these microbial communities. Sediment samples were collected from three glacial lakes, viz., Plav Lake (in a zone of the highest impact of human population), Black Lake (a zone of medium impact of human population), and Donje Bare Lake (a remote lake with minimal impact of human population). Canonical correlation analysis analysis indicated correlation between the distance of the lake from urbanized population and bacterial diversity in Donje Bare Lake sediment. Bacterial diversity of Black Lake sediment was correlated with high content of phosphorous and pH value. Chemical compounds exhibiting the most prominent correlation with bacterial diversity of Plav Lake were NH4-N, K2O, CaCo3, and total nitrogen . Additionally, CCA analysis indicated that population density was correlated with biodiversity of bacterial communities in Plav Lake sediment, which is the most exposed to human population. Multivariate regression revealed the highest correlation between the presence of Proteobacteria classes and population density and levels of NH4-N. The influence of human population was observed to be important for shaping the sediment communities in addition to biological and chemical factors.
PB  - Taylor & Francis
T2  - Geomicrobiology Journal
T1  - Bacterial Diversity among the Sediments of Glacial Lakes in the Western Balkans: Exploring the Impact of Human Population
EP  - 270
IS  - 3
SP  - 261
VL  - 36
DO  - 10.1080/01490451.2018.1550128
ER  - 
@article{
author = "Malešević, Milka and Mirković, Nemanja and Lozo, Jelena and Novović, Katarina and Filipić, Brankica and Kojić, Milan and Jovčić, Branko",
year = "2019",
abstract = "16S rRNA gene-based metagenomic approach was used to assess the biodiversity of bacterial communities in the sediments of selected glacial lakes in the Western Balkans and to assess the impact of human population on these microbial communities. Sediment samples were collected from three glacial lakes, viz., Plav Lake (in a zone of the highest impact of human population), Black Lake (a zone of medium impact of human population), and Donje Bare Lake (a remote lake with minimal impact of human population). Canonical correlation analysis analysis indicated correlation between the distance of the lake from urbanized population and bacterial diversity in Donje Bare Lake sediment. Bacterial diversity of Black Lake sediment was correlated with high content of phosphorous and pH value. Chemical compounds exhibiting the most prominent correlation with bacterial diversity of Plav Lake were NH4-N, K2O, CaCo3, and total nitrogen . Additionally, CCA analysis indicated that population density was correlated with biodiversity of bacterial communities in Plav Lake sediment, which is the most exposed to human population. Multivariate regression revealed the highest correlation between the presence of Proteobacteria classes and population density and levels of NH4-N. The influence of human population was observed to be important for shaping the sediment communities in addition to biological and chemical factors.",
publisher = "Taylor & Francis",
journal = "Geomicrobiology Journal",
title = "Bacterial Diversity among the Sediments of Glacial Lakes in the Western Balkans: Exploring the Impact of Human Population",
pages = "270-261",
number = "3",
volume = "36",
doi = "10.1080/01490451.2018.1550128"
}
Malešević, M., Mirković, N., Lozo, J., Novović, K., Filipić, B., Kojić, M.,& Jovčić, B.. (2019). Bacterial Diversity among the Sediments of Glacial Lakes in the Western Balkans: Exploring the Impact of Human Population. in Geomicrobiology Journal
Taylor & Francis., 36(3), 261-270.
https://doi.org/10.1080/01490451.2018.1550128
Malešević M, Mirković N, Lozo J, Novović K, Filipić B, Kojić M, Jovčić B. Bacterial Diversity among the Sediments of Glacial Lakes in the Western Balkans: Exploring the Impact of Human Population. in Geomicrobiology Journal. 2019;36(3):261-270.
doi:10.1080/01490451.2018.1550128 .
Malešević, Milka, Mirković, Nemanja, Lozo, Jelena, Novović, Katarina, Filipić, Brankica, Kojić, Milan, Jovčić, Branko, "Bacterial Diversity among the Sediments of Glacial Lakes in the Western Balkans: Exploring the Impact of Human Population" in Geomicrobiology Journal, 36, no. 3 (2019):261-270,
https://doi.org/10.1080/01490451.2018.1550128 . .
6
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Functional Characterization of the Lactolisterin BU Gene Cluster of Lactococcus lactis subsp. lactis BGBU1-4

Miljković, Manja; Lozo, Jelena; Mirković, Nemanja; O'Connor, Paula M.; Malešević, Milka; Jovčić, Branko; Cotter, Paul D.; Kojić, Milan

(Frontiers Media Sa, Lausanne, 2018)

TY  - JOUR
AU  - Miljković, Manja
AU  - Lozo, Jelena
AU  - Mirković, Nemanja
AU  - O'Connor, Paula M.
AU  - Malešević, Milka
AU  - Jovčić, Branko
AU  - Cotter, Paul D.
AU  - Kojić, Milan
PY  - 2018
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1124
UR  - http://intor.torlakinstitut.com/handle/123456789/743
AB  - The gene cluster responsible for the production of the aureocin A53-like bacteriocin, lactolisterin BU, is located on plasmid pBU6 in Lactococcus lactis subsp. lactis BGBU1-4. Heterologous expression of pBU6 confirmed that production and limited immunity to lactolisterin BU were provided by the plasmid. Comparative analysis of aureocin A53-like operons revealed that the structural genes shared a low level of identity, while other genes were without homology, indicating a different origin. Subcloning and expression of genes located downstream of the structural gene, IliBU, revealed that the lactolisterin BU cluster consists of four genes: the structural gene IliBU, the abcT gene encoding an ABC transporter, the accL gene encoding an accessory protein and the immL gene which provides limited immunity to lactolisterin BU. Reverse transcription analysis revealed that all genes were transcribed as one polycistronic mRNA. Attempts to split the lactolisterin BU operon, even when both parts were under control of the PlliBU promoter, were unsuccessful indicating that expression of lactolisterin BU is probably precisely regulated at the translational level by translational coupling and is possible only when all genes of the operon are in cis constellation. Two rho-independent transcription terminators were detected in the lactolisterin BU operon: the first in the intergenic region of the IliBU and abcT genes and the second at the end of operon. Deletion of the second transcription terminator did not influence production of the bacteriocin in lactococci.
PB  - Frontiers Media Sa, Lausanne
T2  - Frontiers in Microbiology
T1  - Functional Characterization of the Lactolisterin BU Gene Cluster of Lactococcus lactis subsp. lactis BGBU1-4
VL  - 9
DO  - 10.3389/fmicb.2018.02774
ER  - 
@article{
author = "Miljković, Manja and Lozo, Jelena and Mirković, Nemanja and O'Connor, Paula M. and Malešević, Milka and Jovčić, Branko and Cotter, Paul D. and Kojić, Milan",
year = "2018",
abstract = "The gene cluster responsible for the production of the aureocin A53-like bacteriocin, lactolisterin BU, is located on plasmid pBU6 in Lactococcus lactis subsp. lactis BGBU1-4. Heterologous expression of pBU6 confirmed that production and limited immunity to lactolisterin BU were provided by the plasmid. Comparative analysis of aureocin A53-like operons revealed that the structural genes shared a low level of identity, while other genes were without homology, indicating a different origin. Subcloning and expression of genes located downstream of the structural gene, IliBU, revealed that the lactolisterin BU cluster consists of four genes: the structural gene IliBU, the abcT gene encoding an ABC transporter, the accL gene encoding an accessory protein and the immL gene which provides limited immunity to lactolisterin BU. Reverse transcription analysis revealed that all genes were transcribed as one polycistronic mRNA. Attempts to split the lactolisterin BU operon, even when both parts were under control of the PlliBU promoter, were unsuccessful indicating that expression of lactolisterin BU is probably precisely regulated at the translational level by translational coupling and is possible only when all genes of the operon are in cis constellation. Two rho-independent transcription terminators were detected in the lactolisterin BU operon: the first in the intergenic region of the IliBU and abcT genes and the second at the end of operon. Deletion of the second transcription terminator did not influence production of the bacteriocin in lactococci.",
publisher = "Frontiers Media Sa, Lausanne",
journal = "Frontiers in Microbiology",
title = "Functional Characterization of the Lactolisterin BU Gene Cluster of Lactococcus lactis subsp. lactis BGBU1-4",
volume = "9",
doi = "10.3389/fmicb.2018.02774"
}
Miljković, M., Lozo, J., Mirković, N., O'Connor, P. M., Malešević, M., Jovčić, B., Cotter, P. D.,& Kojić, M.. (2018). Functional Characterization of the Lactolisterin BU Gene Cluster of Lactococcus lactis subsp. lactis BGBU1-4. in Frontiers in Microbiology
Frontiers Media Sa, Lausanne., 9.
https://doi.org/10.3389/fmicb.2018.02774
Miljković M, Lozo J, Mirković N, O'Connor PM, Malešević M, Jovčić B, Cotter PD, Kojić M. Functional Characterization of the Lactolisterin BU Gene Cluster of Lactococcus lactis subsp. lactis BGBU1-4. in Frontiers in Microbiology. 2018;9.
doi:10.3389/fmicb.2018.02774 .
Miljković, Manja, Lozo, Jelena, Mirković, Nemanja, O'Connor, Paula M., Malešević, Milka, Jovčić, Branko, Cotter, Paul D., Kojić, Milan, "Functional Characterization of the Lactolisterin BU Gene Cluster of Lactococcus lactis subsp. lactis BGBU1-4" in Frontiers in Microbiology, 9 (2018),
https://doi.org/10.3389/fmicb.2018.02774 . .
2
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9

Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells

Novović, Katarina; Mihajlović, Sanja; Dinić, Miroslav; Malešević, Milka; Miljković, Marija; Kojić, Milan; Jovčić, Branko

(Public Library Science, San Francisco, 2018)

TY  - JOUR
AU  - Novović, Katarina
AU  - Mihajlović, Sanja
AU  - Dinić, Miroslav
AU  - Malešević, Milka
AU  - Miljković, Marija
AU  - Kojić, Milan
AU  - Jovčić, Branko
PY  - 2018
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/1119
UR  - http://intor.torlakinstitut.com/handle/123456789/684
AB  - Acinetobacter baumannii has been recognized as one of the most challeging pathogens in clinical settings worldwide. Outer membrane porins play a significant role in Acinetobacter antibiotic resistance and virulence. A. baumannii carbapenem resistance and virulence factor porin Omp33-36 was the subject of this study. We investigated the omp33-36 gene transcriptional response in the growth phase, its response to carbapenems, and the effect of contact with host cells. Additionally, the cytotoxic effect of A. baumannii towards keratinocytes was assessed, as well as correlation between omp33-36 gene transcription and cytotoxicity. Further, Acinetobacter spp. Omp33-36 was classified and its characteristics relevant for vaccine candidature were determined. The level of the omp33-36 gene transcription varied between growth phases, but a common pattern could not be established among different strains. Treatment with subinhibitory concentrations of carbapenems decreased, while contact with keratinocytes increased omp33-36 expression in the analysed A. baumannii strains. Variations in omp33-36 mRNA levels did not correlate with cytotoxicity levels. Decrease of omp33-36 mRNA during treatment with subinhibitory concentrations of carbapenems, indicated the importance of transcriptional changes in reversible resistance to carbapenems due to the absence of Omp33-36. The transcription of omp33-36 increased after contact with keratinocytes, indicating the important role of de novo transcription during the initial phase of A. baumannii infection. Primary structural analysis of Acinetobacter spp. Omp33-36 revealed three distinct groups (among four A. baumannii variants). Although we have shown that Omp33-36 was highly polymorphic, we propose a potential antigen (PLAEAAFL motif) for vaccine development. According to PROVEAN analysis, the highly polymorphic structure of Omp33-36 porin should not influence its function significantly.
PB  - Public Library Science, San Francisco
T2  - PLoS One
T1  - Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells
IS  - 8
VL  - 13
DO  - 10.1371/journal.pone.0201608
ER  - 
@article{
author = "Novović, Katarina and Mihajlović, Sanja and Dinić, Miroslav and Malešević, Milka and Miljković, Marija and Kojić, Milan and Jovčić, Branko",
year = "2018",
abstract = "Acinetobacter baumannii has been recognized as one of the most challeging pathogens in clinical settings worldwide. Outer membrane porins play a significant role in Acinetobacter antibiotic resistance and virulence. A. baumannii carbapenem resistance and virulence factor porin Omp33-36 was the subject of this study. We investigated the omp33-36 gene transcriptional response in the growth phase, its response to carbapenems, and the effect of contact with host cells. Additionally, the cytotoxic effect of A. baumannii towards keratinocytes was assessed, as well as correlation between omp33-36 gene transcription and cytotoxicity. Further, Acinetobacter spp. Omp33-36 was classified and its characteristics relevant for vaccine candidature were determined. The level of the omp33-36 gene transcription varied between growth phases, but a common pattern could not be established among different strains. Treatment with subinhibitory concentrations of carbapenems decreased, while contact with keratinocytes increased omp33-36 expression in the analysed A. baumannii strains. Variations in omp33-36 mRNA levels did not correlate with cytotoxicity levels. Decrease of omp33-36 mRNA during treatment with subinhibitory concentrations of carbapenems, indicated the importance of transcriptional changes in reversible resistance to carbapenems due to the absence of Omp33-36. The transcription of omp33-36 increased after contact with keratinocytes, indicating the important role of de novo transcription during the initial phase of A. baumannii infection. Primary structural analysis of Acinetobacter spp. Omp33-36 revealed three distinct groups (among four A. baumannii variants). Although we have shown that Omp33-36 was highly polymorphic, we propose a potential antigen (PLAEAAFL motif) for vaccine development. According to PROVEAN analysis, the highly polymorphic structure of Omp33-36 porin should not influence its function significantly.",
publisher = "Public Library Science, San Francisco",
journal = "PLoS One",
title = "Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells",
number = "8",
volume = "13",
doi = "10.1371/journal.pone.0201608"
}
Novović, K., Mihajlović, S., Dinić, M., Malešević, M., Miljković, M., Kojić, M.,& Jovčić, B.. (2018). Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells. in PLoS One
Public Library Science, San Francisco., 13(8).
https://doi.org/10.1371/journal.pone.0201608
Novović K, Mihajlović S, Dinić M, Malešević M, Miljković M, Kojić M, Jovčić B. Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells. in PLoS One. 2018;13(8).
doi:10.1371/journal.pone.0201608 .
Novović, Katarina, Mihajlović, Sanja, Dinić, Miroslav, Malešević, Milka, Miljković, Marija, Kojić, Milan, Jovčić, Branko, "Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells" in PLoS One, 13, no. 8 (2018),
https://doi.org/10.1371/journal.pone.0201608 . .
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