TY  - JOUR
AU  - Mirković, Nemanja
AU  - Polović, Natalija
AU  - Vukotić, Goran
AU  - Jovcić, Branko
AU  - Miljković, Marija
AU  - Radulović, Zorica
AU  - Diep, Dzung B.
AU  - Kojić, Milan
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4208
AB  - Bacteriocin producers normally possess dedicated immunity systems to protect themselves from their own bacteriocins. Lactococcus lactis strains LMG2081 and BGBM50 are known as lactococcin G producers. However, BGBM50 was sensitive to LMG2081, which indicated that LMG2081 might produce additional bacteriocins that are not present in BGBM50. Therefore, whole-genome sequencing of the two strains was performed, and a lantibiotic operon (called lctLMG) was identified in LMG2081 but not in BGBM50. The lctLMG operon contains six open reading frames; the first three genes, lmgA, lmgM, and lmgT, are involved in the biosynthesis and export of bacteriocin, while the other three genes, lmgF, lmgE, and lmgG, are involved in lantibiotic immunity. Mutational analysis confirmed that the lctLMG operon is responsible for the additional antimicrobial activity. Specifically, site-directed mutation within this operon rendered LMG2081 inactive toward BGBM50. Subsequent purification and electrospray ionization-time of flight mass spectrometric analysis confirmed that the lantibiotic bacteriocin called lacticin LMG is exported as a 25-amino-acid peptide. Lacticin LMG is highly similar to the lacticin 481 group. It is interesting that a bacteriocin producer produces two different classes of bacteriocins, whose operons are located in the chromosome and a plasmid.
PB  - Amer Soc Microbiology, Washington
T2  - Applied and Environmental Microbiology
T1  - Lactococcus lactis LMG2081 Produces Two Bacteriocins, a Nonlantibiotic and a Novel Lantibiotic
EP  - 2562
IS  - 8
SP  - 2555
VL  - 82
DO  - 10.1128/AEM.03988-15
ER  - 

@article{
author = "Mirković, Nemanja and Polović, Natalija and Vukotić, Goran and Jovcić, Branko and Miljković, Marija and Radulović, Zorica and Diep, Dzung B. and Kojić, Milan",
year = "2016",
abstract = "Bacteriocin producers normally possess dedicated immunity systems to protect themselves from their own bacteriocins. Lactococcus lactis strains LMG2081 and BGBM50 are known as lactococcin G producers. However, BGBM50 was sensitive to LMG2081, which indicated that LMG2081 might produce additional bacteriocins that are not present in BGBM50. Therefore, whole-genome sequencing of the two strains was performed, and a lantibiotic operon (called lctLMG) was identified in LMG2081 but not in BGBM50. The lctLMG operon contains six open reading frames; the first three genes, lmgA, lmgM, and lmgT, are involved in the biosynthesis and export of bacteriocin, while the other three genes, lmgF, lmgE, and lmgG, are involved in lantibiotic immunity. Mutational analysis confirmed that the lctLMG operon is responsible for the additional antimicrobial activity. Specifically, site-directed mutation within this operon rendered LMG2081 inactive toward BGBM50. Subsequent purification and electrospray ionization-time of flight mass spectrometric analysis confirmed that the lantibiotic bacteriocin called lacticin LMG is exported as a 25-amino-acid peptide. Lacticin LMG is highly similar to the lacticin 481 group. It is interesting that a bacteriocin producer produces two different classes of bacteriocins, whose operons are located in the chromosome and a plasmid.",
publisher = "Amer Soc Microbiology, Washington",
journal = "Applied and Environmental Microbiology",
title = "Lactococcus lactis LMG2081 Produces Two Bacteriocins, a Nonlantibiotic and a Novel Lantibiotic",
pages = "2562-2555",
number = "8",
volume = "82",
doi = "10.1128/AEM.03988-15"
}

Mirković, N., Polović, N., Vukotić, G., Jovcić, B., Miljković, M., Radulović, Z., Diep, D. B.,& Kojić, M.. (2016). Lactococcus lactis LMG2081 Produces Two Bacteriocins, a Nonlantibiotic and a Novel Lantibiotic. in Applied and Environmental Microbiology
Amer Soc Microbiology, Washington., 82(8), 2555-2562.
https://doi.org/10.1128/AEM.03988-15

Mirković N, Polović N, Vukotić G, Jovcić B, Miljković M, Radulović Z, Diep DB, Kojić M. Lactococcus lactis LMG2081 Produces Two Bacteriocins, a Nonlantibiotic and a Novel Lantibiotic. in Applied and Environmental Microbiology. 2016;82(8):2555-2562.
doi:10.1128/AEM.03988-15 .

Mirković, Nemanja, Polović, Natalija, Vukotić, Goran, Jovcić, Branko, Miljković, Marija, Radulović, Zorica, Diep, Dzung B., Kojić, Milan, "Lactococcus lactis LMG2081 Produces Two Bacteriocins, a Nonlantibiotic and a Novel Lantibiotic" in Applied and Environmental Microbiology, 82, no. 8 (2016):2555-2562,
https://doi.org/10.1128/AEM.03988-15 . .

TY  - JOUR
AU  - Miljković, Marija
AU  - Uzelac, Gordana
AU  - Mirković, Nemanja
AU  - Devescovi, Giulia
AU  - Diep, Dzung B.
AU  - Venturi, Vittorio
AU  - Kojić, Milan
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4029
AB  - The Zn-dependent membrane-located protease YvjB has previously been shown to serve as a target receptor for LsbB, a class II leaderless lactococcal bacteriocin. Although yvjB is highly conserved in the genus Lactococcus, the bacteriocin appears to be active only against the subspecies L. lactis subsp. lactis. Comparative analysis of the YvjB proteins of a sensitive strain (YvjB(MN)) and a resistant strain (YvjB(MG)) showed that they differ from each other in 31 positions. In this study, we applied site-directed mutagenesis and performed directed binding studies to provide biochemical evidence that LsbB interacts with the third transmembrane helix of YvjB in susceptible cells. The site-directed mutagenesis of LsbB and YvjB proteins showed that certain amino acids and the length of LsbB are responsible for the bacteriocin activity, most probably through adequate interaction of these two proteins; the essential amino acids in LsbB responsible for the activity are tryptophan (Trp(25)) and terminal alanine (Ala(30)). It was also shown that the distance between Trp(25) and terminal alanine is crucial for LsbB activity. The crucial region in YvjB for the interaction with LsbB is the beginning of the third transmembrane helix, particularly amino acids tyrosine (Tyr(356)) and alanine (Ala(353)). In vitro experiments showed that LsbB could interact with both YvjB(MN) and YvjB(MG), but the strength of interaction is significantly less with YvjB(MG). In vivo experiments with immunofluorescently labeled antibody demonstrated that LsbB specifically interacts only with cells carrying YvjB(MN). IMPORTANCE The antimicrobial activity of LsbB bacteriocin depends on the correct interaction with the corresponding receptor in the bacterial membrane of sensitive cells. Membrane-located bacteriocin receptors have essential primary functions, such as cell wall synthesis or sugar transport, and it seems that interaction with bacteriocins is suicidal for cells. This study showed that the C-terminal part of LsbB is crucial for the bacteriocin activity, most probably through adequate interaction with the third transmembrane domain of the YvjB receptor. The conserved Tyr(356) and Ala(353) residues of YvjB are essential for the function of this Zn-dependent membrane-located protease as a bacteriocin receptor.
PB  - Amer Soc Microbiology, Washington
T2  - Applied and Environmental Microbiology
T1  - LsbB Bacteriocin Interacts with the Third Transmembrane Domain of the YvjB Receptor
EP  - 5374
IS  - 17
SP  - 5364
VL  - 82
DO  - 10.1128/AEM.01293-16
ER  - 

@article{
author = "Miljković, Marija and Uzelac, Gordana and Mirković, Nemanja and Devescovi, Giulia and Diep, Dzung B. and Venturi, Vittorio and Kojić, Milan",
year = "2016",
abstract = "The Zn-dependent membrane-located protease YvjB has previously been shown to serve as a target receptor for LsbB, a class II leaderless lactococcal bacteriocin. Although yvjB is highly conserved in the genus Lactococcus, the bacteriocin appears to be active only against the subspecies L. lactis subsp. lactis. Comparative analysis of the YvjB proteins of a sensitive strain (YvjB(MN)) and a resistant strain (YvjB(MG)) showed that they differ from each other in 31 positions. In this study, we applied site-directed mutagenesis and performed directed binding studies to provide biochemical evidence that LsbB interacts with the third transmembrane helix of YvjB in susceptible cells. The site-directed mutagenesis of LsbB and YvjB proteins showed that certain amino acids and the length of LsbB are responsible for the bacteriocin activity, most probably through adequate interaction of these two proteins; the essential amino acids in LsbB responsible for the activity are tryptophan (Trp(25)) and terminal alanine (Ala(30)). It was also shown that the distance between Trp(25) and terminal alanine is crucial for LsbB activity. The crucial region in YvjB for the interaction with LsbB is the beginning of the third transmembrane helix, particularly amino acids tyrosine (Tyr(356)) and alanine (Ala(353)). In vitro experiments showed that LsbB could interact with both YvjB(MN) and YvjB(MG), but the strength of interaction is significantly less with YvjB(MG). In vivo experiments with immunofluorescently labeled antibody demonstrated that LsbB specifically interacts only with cells carrying YvjB(MN). IMPORTANCE The antimicrobial activity of LsbB bacteriocin depends on the correct interaction with the corresponding receptor in the bacterial membrane of sensitive cells. Membrane-located bacteriocin receptors have essential primary functions, such as cell wall synthesis or sugar transport, and it seems that interaction with bacteriocins is suicidal for cells. This study showed that the C-terminal part of LsbB is crucial for the bacteriocin activity, most probably through adequate interaction with the third transmembrane domain of the YvjB receptor. The conserved Tyr(356) and Ala(353) residues of YvjB are essential for the function of this Zn-dependent membrane-located protease as a bacteriocin receptor.",
publisher = "Amer Soc Microbiology, Washington",
journal = "Applied and Environmental Microbiology",
title = "LsbB Bacteriocin Interacts with the Third Transmembrane Domain of the YvjB Receptor",
pages = "5374-5364",
number = "17",
volume = "82",
doi = "10.1128/AEM.01293-16"
}

Miljković, M., Uzelac, G., Mirković, N., Devescovi, G., Diep, D. B., Venturi, V.,& Kojić, M.. (2016). LsbB Bacteriocin Interacts with the Third Transmembrane Domain of the YvjB Receptor. in Applied and Environmental Microbiology
Amer Soc Microbiology, Washington., 82(17), 5364-5374.
https://doi.org/10.1128/AEM.01293-16

Miljković M, Uzelac G, Mirković N, Devescovi G, Diep DB, Venturi V, Kojić M. LsbB Bacteriocin Interacts with the Third Transmembrane Domain of the YvjB Receptor. in Applied and Environmental Microbiology. 2016;82(17):5364-5374.
doi:10.1128/AEM.01293-16 .

Miljković, Marija, Uzelac, Gordana, Mirković, Nemanja, Devescovi, Giulia, Diep, Dzung B., Venturi, Vittorio, Kojić, Milan, "LsbB Bacteriocin Interacts with the Third Transmembrane Domain of the YvjB Receptor" in Applied and Environmental Microbiology, 82, no. 17 (2016):5364-5374,
https://doi.org/10.1128/AEM.01293-16 . .