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Manuel A Ortega, Dillon P Cogan, Subha Mukherjee, Neha Garg, Bo Li, Gabrielle N Thibodeaux, Sonia I Maffioli, Stefano Donadio, Margherita Sosio, Jerome Escano, Leif Smith, Satish K Nair, Wilfred A van der Donk
Lantibiotics are ribosomally synthesized and post-translationally modified antimicrobial peptides containing thioether rings. In addition to these cross-links, the clinical candidate lantibiotic NAI-107 also possesses a C-terminal S-[(Z)-2-aminovinyl]-d-cysteine (AviCys) and a unique 5-chloro-l-tryptophan (ClTrp) moiety linked to its potent bioactivity. Bioinformatic and genetic analyses on the NAI-107 biosynthetic gene cluster identified mibH and mibD as genes encoding flavoenzymes responsible for the formation of ClTrp and AviCys, respectively...
January 13, 2017: ACS Chemical Biology
Ammar Algburi, Saskia Zehm, Victoria Netrebov, Anzhelica B Bren, Vladimir Chistyakov, Michael L Chikindas
Subtilosin, the cyclic lantibiotic protein produced by Bacillus subtilis KATMIRA1933, targets the surface receptor and electrostatically binds to the bacterial cell membrane. In this study, subtilosin was purified using ammonium sulfate ((NH4)2SO4) precipitation and purified via column chromatography. Subtilosin's antibacterial minimum and sub-minimum inhibitory concentrations (MIC and sub-MIC) and anti-biofilm activity (biofilm prevention) were established. Subtilosin was evaluated as a quorum sensing (QS) inhibitor in Gram-positive bacteria using Fe(III) reduction assay...
December 2, 2016: Probiotics and Antimicrobial Proteins
Karen Gomes, Rafael Silva Duarte, Maria do Carmo de Freire Bastos
The phylum Actinobacteria, which comprises a great variety of Gram-positive bacteria with a high G+C content in their genomes, is known for its large production of bioactive compounds, including those with antimicrobial activity. Among the antimicrobials, bacteriocins, ribosomally-synthesized peptides, represent an important arsenal of potential new drugs to face the increasing prevalence of resistance to antibiotics among microbial pathogens. The actinobacterial bacteriocins form a heterogeneous group of substances that is difficult to adapt to most proposed classification schemes...
November 22, 2016: Microbiology
Liujie Huo, Ayşe Ökesli, Ming Zhao, Wilfred A van der Donk
: Lantibiotics are ribosomally synthesized and post-translationally modified antimicrobial peptides that are characterized by the thioether cross-linked bisamino acids lanthionine (Lan) and methyllanthionine (MeLan). Duramycin contains 19 amino acids including one Lan and two MeLan, an unusual lysinoalanine (Lal) bridge formed from the ϵ-amino group of lysine 19 and a serine residue at position 6, and an erythro-3-hydroxy-L-aspartic acid at position 15. These modifications are important for the interactions of duramycin with its biological target phosphatidylethanolamine (PE)...
November 18, 2016: Applied and Environmental Microbiology
Sean O'Rourke, David Widdick, Mervyn Bibb
Streptomyces cinnamoneus DSM 40646 produces the Class II lantibiotic cinnamycin which possesses an unusual mechanism of action, binding to the membrane lipid phosphatidylethanolamine (PE) to elicit its antimicrobial activity. A comprehensive analysis of the cinnamycin biosynthetic gene cluster has unveiled a novel mechanism of immunity in which the producing organism methylates its entire complement of PE prior to the onset of cinnamycin production. Deletion of the PE methyl transferase gene cinorf10, or the two-component regulatory system (cinKR) that controls its expression, leads not only to sensitivity to the closely related lantibiotic duramycin, but also abolishes cinnamycin production, presumably reflecting a fail-safe mechanism that serves to ensure that biosynthesis does not occur until immunity has been established...
November 17, 2016: Journal of Industrial Microbiology & Biotechnology
Khaled M Elsayed, Mohammad R Islam, Abdullah-Al-Mahin, Jun-Ichi Nagao, Takeshi Zendo, Kenji Sonomoto
Binding to lipid II is an important step in the mode of action of most lantibiotics targeting the bacterial cell wall. We applied the Bacillus subtilis two-component system, LiaRS, that is known to respond to antibiotics interfering with lipid II cycle, in order to evaluate lipid II binding activity of known bacteriocins and also to identify lipid II binding moieties in lantibiotic nukacin ISK-1. Using this method, we confirmed that the methyllanthionine ring in nukacin ISK-1 is crucial for lipid II binding as previously indicated...
November 14, 2016: Journal of Bioscience and Bioengineering
Annechien Plat, Anneke Kuipers, Joe Crabb, Rick Rink, Gert N Moll
The lantibiotic nisin is produced by Lactococcus lactis as a precursor peptide comprising a 23 amino acid leader peptide and a 34 amino acid post-translationally modifiable core peptide. We previously demonstrated that the conserved FNLD part of the leader is essential for intracellular enzyme-catalyzed introduction of lanthionines in the core peptide and also for transporter-mediated export, whereas other positions are subject to large mutational freedom. We here demonstrate that, in the absence of the extracellular leader peptidase, NisP, export of precursor nisin via the modification and transporter enzymes, NisBTC, is strongly affected by multiple substitutions of the leader residue at position -2, but not by substitution of positions in the vicinity of this site...
November 10, 2016: Antonie Van Leeuwenhoek
Srinivas Suda, Des Field, Niall Barron
Antimicrobial peptides (AMPs) are natural defense compounds which are synthesized as ribosomal gene-encoded pre-peptides and produced by all living organisms. AMPs are small peptides, usually cationic and typically have hydrophobic residues which interact with cell membranes and have either a narrow or broad spectrum of biological activity. AMPs are isolated from the natural host or heterologously expressed in other hosts such as Escherichia coli. The proto-typical lantibiotic Nisin is a widely used AMP that is produced by the food-grade organism Lactococcus lactis...
2017: Methods in Molecular Biology
Marcus Lívio Varella Coelho, Andreza Freitas de Souza Duarte, Maria do Carmo de Freire Bastos
One of the biggest challenges faced presently by clinicians is the emergence of multi drug--resistant pathogens that can infect humans and animals.To control the infections caused by such pathogens the development of new drugs is required. Bacteria are a rich source of ribosomally-synthesized antimicrobial peptides known as bacteriocins, which are characterized by the presence of a self-defense immunity system. Labionin-containing lantibiotics and sactibiotics are post-translationally modified bacteriocins with peculiar features...
September 30, 2016: Current Topics in Medicinal Chemistry
Françoise Hullin-Matsuda, Asami Makino, Motohide Murate, Toshihide Kobayashi
In this mini-review, we summarize current knowledge about the lipid-binding characteristics of two types of toxins used to visualize the membrane distribution of phosphoethanolamine-containing lipid species: the glycerophospholipid, phosphatidylethanolamine (PE) and the sphingolipid, ceramide phosphoethanolamine (CPE). The lantibiotic cinnamycin and the structurally-related peptide duramycin produced by some Gram-positive bacteria were among the first toxins characterized by their specificity for PE which is widely present in animal kingdoms from bacteria to mammals...
November 2016: Biochimie
Josephine C Moran, Emma L Crank, Hanaa A Ghabban, Malcolm J Horsburgh
Competitive exclusion can occur in microbial communities when, for example, an inhibitor-producing strain outcompetes its competitor for an essential nutrient or produces antimicrobial compounds that its competitor is not resistant to. Here we describe a deferred growth inhibition assay, a method for assessing the ability of one bacterium to inhibit the growth of another through the production of antimicrobial compounds or through competition for nutrients. This technique has been used to investigate the correlation of nasal isolates with the exclusion of particular species from a community...
September 3, 2016: Journal of Visualized Experiments: JoVE
Juan M Palazzini, Christopher A Dunlap, Michael J Bowman, Sofía N Chulze
Bacillus subtilis RC 218 was originally isolated from wheat anthers as a potential antagonist of Fusarium graminearum, the causal agent of Fusarium head blight (FHB). It was demonstrated to have antagonist activity against the plant pathogen under in vitro and greenhouse assays. The current study extends characterizing B. subtilis RC 218 with a field study and genome sequencing. The field study demonstrated that B. subtilis RC 218 could reduce disease severity and the associated mycotoxin (deoxynivalenol) accumulation, under field conditions...
November 2016: Microbiological Research
Anja Kuthning, Patrick Durkin, Stefan Oehm, Michael G Hoesl, Nediljko Budisa, Roderich D Süssmuth
Genetic code engineering that enables reassignment of genetic codons to non-canonical amino acids (ncAAs) is a powerful strategy for enhancing ribosomally synthesized peptides and proteins with functions not commonly found in Nature. Here we report the expression of a ribosomally synthesized and post-translationally modified peptide (RiPP), the 32-mer lantibiotic lichenicidin with a canonical tryptophan (Trp) residue replaced by the ncAA L-β-(thieno[3,2-b]pyrrolyl)alanine ([3,2]Tpa) which does not sustain cell growth in the culture...
2016: Scientific Reports
Manuel Montalbán-López, Auke J van Heel, Oscar P Kuipers
As the number of new antibiotics that reach the market is decreasing and the demand for them is rising, alternative sources of novel antimicrobials are needed. Lantibiotics are potent peptide antimicrobials that are ribosomally synthesized and stabilized by post-translationally introduced lanthionine rings. Their ribosomal synthesis and enzymatic modifications provide excellent opportunities to design and engineer a large variety of novel antimicrobial compounds. The research conducted in this area demonstrates that the modularity present in both the peptidic rings as well as in the combination of promiscuous modification enzymes can be exploited to further increase the diversity of lantibiotics...
September 2, 2016: FEMS Microbiology Reviews
Abdelahhad Barbour, John Tagg, Osama K Abou-Zied, Koshy Philip
Salivaricin B is a 25 amino acid polycyclic peptide belonging to the type AII lantibiotics and first shown to be produced by Streptococcus salivarius. In this study we describe the bactericidal mode of action of salivaricin B against susceptible Gram-positive bacteria. The killing action of salivaricin B required micro-molar concentrations of lantibiotic whereas the prototype lantibiotic nisin A was shown to be potent at nano-molar levels. Unlike nisin A, salivaricin B did not induce pore formation or dissipate the membrane potential in susceptible cells...
2016: Scientific Reports
Min-Jung Kwak, Soon-Kyeong Kwon, Jae-Kyung Yoon, Ju Yeon Song, Jae-Gu Seo, Myung Jun Chung, Jihyun F Kim
Bifidobacteria, often associated with the gastrointestinal tract of animals, are well known for their roles as probiotics. Among the dozens of Bifidobacterium species, Bifidobacterium bifidum, B. breve, and B. longum are the ones most frequently isolated from the feces of infants and known to help the digestion of human milk oligosaccharides. To investigate the correlation between the metabolic properties of bifidobacteria and their phylogeny, we performed a phylogenomic analysis based on 452 core genes of forty-four completely sequenced Bifidobacterium species...
October 2016: Systematic and Applied Microbiology
Bingyue Xin, Jinshui Zheng, Hualin Liu, Junhua Li, Lifang Ruan, Donghai Peng, Muhammad Sajid, Ming Sun
Due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. Bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. Among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant Gram-positive pathogens and have potential applications in the pharmaceutical industry...
2016: Frontiers in Microbiology
Miki Kawada-Matsuo, Ichiro Tatsuno, Kaoru Arii, Takeshi Zendo, Yuichi Oogai, Kazuyuki Noguchi, Tadao Hasegawa, Kenji Sonomoto, Hitoshi Komatsuzawa
UNLABELLED: Two-component systems (TCSs) are regulatory systems in bacteria that play important roles in sensing and adapting to the environment. In this study, we systematically evaluated the roles of TCSs in the susceptibility of the group A Streptococcus (GAS; Streptococcus pyogenes) SF370 strain to several types of lantibiotics. Using individual TCS deletion mutants, we found that the deletion of srtRK (spy_1081-spy_1082) in SF370 increased the susceptibility to nisin A, which is produced by Lactococcus lactis ATCC 11454, but susceptibility to other types of lantibiotics (nukacin ISK-1, produced by Staphylococcus warneri, and staphylococcin C55, produced by Staphylococcus aureus) was not altered in the TCS mutants tested...
October 1, 2016: Applied and Environmental Microbiology
Muhammad Imran, Anne-Marie Revol-Junelles, Grégory Francius, Stéphane Desobry
Application of nano-biotechnology to improve the controlled release of drugs or functional agents is widely anticipated to transform the biomedical, pharmaceutical, and food safety trends. The purpose of the current study was to assess and compare the release rates of fluorescently labeled antimicrobial peptide nisin (lantibiotic/biopreservative) from liposomal nanocarriers. The elevated temperature, high electrostatic attraction between anionic bilayers and cationic nisin, larger size, and higher encapsulation efficiency resulted in rapid and elevated release through pore formation...
August 24, 2016: ACS Applied Materials & Interfaces
Fergus W J Collins, Paula M O'Connor, Orla O'Sullivan, Mary C Rea, Colin Hill, R Paul Ross
Bacteriocins represent a rather underutilized class of antimicrobials despite often displaying activity against many drug-resistant pathogens. Lantibiotics are a post-translationally modified class of bacteriocins, characterized by the presence of lanthionine and methyllanthionine bridges. In this study, a novel two-peptide lantibiotic was isolated and characterized. Formicin was isolated from Bacillus paralicheniformis APC 1576, an antimicrobial-producing strain originally isolated from the intestine of a mackerel...
September 2016: Microbiology
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