title: Characterization and application of enterocin RM6, a bacteriocin from Enterococcus faecalis.
abstract: Use of bacteriocins in food preservation has received great attention in recent years. The goal of this study is to characterize enterocin RM6 from Enterococcus faecalis OSY-RM6 and investigate its efficacy against Listeria monocytogenes in cottage cheese. Enterocin RM6 was purified from E. faecalis culture supernatant using ion exchange column, multiple C18-silica cartridges, followed by reverse-phase high-performance liquid chromatography. The molecular weight of enterocin RM6 is 7145.0823 as determined by mass spectrometry (MS). Tandem mass spectrometry (MS/MS) analysis revealed that enterocin RM6 is a 70-residue cyclic peptide with a head-to-tail linkage between methionine and tryptophan residues. The peptide sequence of enterocin RM6 was further confirmed by sequencing the structural gene of the peptide. Enterocin RM6 is active against Gram-positive bacteria, including L. monocytogenes, Bacillus cereus, and methicillin-resistant Staphylococcus aureus (MRSA). Enterocin RM6 (final concentration in cottage cheese, 80 AU/mL) caused a 4-log reduction in population of L. monocytogenes inoculated in cottage cheese within 30 min of treatment. Therefore, enterocin RM6 has potential applications as a potent antimicrobial peptide against foodborne pathogens in food.
authors.affiliation: Department of Food Science and Technology, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: En
authors.initials: E
authors.lastname: Huang
authors.forename: Liwen
authors.initials: L
authors.lastname: Zhang
authors.forename: Yoon-Kyung
authors.initials: YK
authors.lastname: Chung
authors.forename: Zuoxing
authors.initials: Z
authors.lastname: Zheng
authors.forename: Ahmed E
authors.initials: AE
authors.lastname: Yousef
mesh_terms: D000595:Amino Acid Sequence; D000890:Anti-Infective Agents / Q000494:pharmacology; D001430:Bacteriocins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D001483:Base Sequence; D002611:Cheese / Q000382:microbiology; D002851:Chromatography, High Pressure Liquid; D045424:Complex Mixtures; D013293:Enterococcus faecalis / Q000378:metabolism*; D008089:Listeria monocytogenes / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D000890:Anti-Infective Agents; D001430:Bacteriocins; D045424:Complex Mixtures; D010455:Peptides; C571347:enterocin S37, Enterococcus faecalis