title: Isolation and Structural Elucidation of Brevibacillin, an Antimicrobial Lipopeptide from Brevibacillus laterosporus That Combats Drug-Resistant Gram-Positive Bacteria.
abstract: A new environmental bacterial strain exhibited strong antimicrobial characteristics against methicillin-resistant Staphylococcus aureus, vancomycin-resistant strains of Enterococcus faecalis and Lactobacillus plantarum, and other Gram-positive bacteria. The producer strain, designated OSY-I1, was determined to be Brevibacillus laterosporusvia morphological, biochemical, and genetic analyses. The antimicrobial agent was extracted from cells of OSY-I1 with isopropanol, purified by high-performance liquid chromatography, and structurally analyzed using mass spectrometry (MS) and nuclear magnetic resonance (NMR). The MS and NMR results, taken together, uncovered a linear lipopeptide consisting of 13 amino acids and an N-terminal C6 fatty acid (FA) chain, 2-hydroxy-3-methylpentanoic acid. The lipopeptide (FA-Dhb-Leu-Orn-Ile-Ile-Val-Lys-Val-Val-Lys-Tyr-Leu-valinol, where Dhb is α,β-didehydrobutyric acid and valinol is 2-amino-3-methyl-1-butanol) has a molecular mass of 1,583.0794 Da and contains three modified amino acid residues: α,β-didehydrobutyric acid, ornithine, and valinol. The compound, designated brevibacillin, was determined to be a member of a cationic lipopeptide antibiotic family. In addition to its potency against drug-resistant bacteria, brevibacillin also exhibited low MICs (1 to 8 μg/ml) against selected foodborne pathogenic and spoilage bacteria, such as Listeria monocytogenes,Bacillus cereus, and Alicyclobacillus acidoterrestris Purified brevibacillin showed no sign of degradation when it was held at 80 °C for 60 min, and it retained at least 50% of its antimicrobial activity when it was held for 22 h under acidic or alkaline conditions. On the basis of these findings, brevibacillin is a potent antimicrobial lipopeptide which is potentially useful to combat drug-resistant bacterial pathogens and foodborne pathogenic and spoilage bacteria.
authors.affiliation: Department of Food Science and Technology, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Xu
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Food Science and Technology, The Ohio State University, Columbus, Ohio, USA.
authors.forename: En
authors.identifier: http://orcid.org/0000-0002-6386-2156
authors.initials: E
authors.lastname: Huang
authors.affiliation: Nuclear Magnetic Resonance Facility, Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Yuan
authors.affiliation: Mass Spectrometry and Proteomics Facility, Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Liwen
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Food Science and Technology, The Ohio State University, Columbus, Ohio, USA yousef.1@osu.edu.|Department of Microbiology, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Ahmed E
authors.initials: AE
authors.lastname: Yousef
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D058675:Brevibacillus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D013293:Enterococcus faecalis / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D048191:Lactiplantibacillus plantarum / Q000187:drug effects; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010421:Pentanoic Acids / Q000737:chemistry; D014633:Valine / Q000031:analogs & derivatives / Q000737:chemistry; D065507:Vancomycin-Resistant Enterococci / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D010421:Pentanoic Acids; C040994:valinol; C035865:2-hydroxy-3-methylvaleric acid; D014633:Valine