title: Ruminococcin C, a new anti-Clostridium perfringens bacteriocin produced in the gut by the commensal bacterium Ruminococcus gnavus E1.
abstract: When colonizing the digestive tract of mono-associated rats, Ruminococcus gnavus E1 - a bacterium isolated from human faeces - produced a trypsin-dependent anti-Clostridium perfringens substance collectively named Ruminococcin C (RumC). RumC was isolated from the caecal contents of E1-monocontaminated rats and found to consist of two antimicrobial fractions: a single peptide (RumCsp) of 4235 Da, and a mixture of two other peptides (RumCdp) with distinct molecular masses of 4324 Da and 4456 Da. Both RumCsp and RumCdp were as effective as metronidazole in combating C. perfringens and their activity spectra against different pathogens were established. Even if devoid of synergistic activity, the combination of RumCsp and RumCdp was observed to be much more resistant to acidic pH and high temperature than each fraction tested individually. N-terminal sequence analysis showed that the primary structures of these three peptides shared a high degree of homology, but were clearly distinct from previously reported amino acid sequences. Amino acid composition of the three RumC peptides did not highlight the presence of any Lanthionine residue. However, Edman degradation could not run beyond the 11th amino acid residue. Five genes encoding putative pre-RumC-like peptides were identified in the genome of strain E1, confirming that RumC was a bacteriocin. This is the first time that a bacteriocin produced in vivo by a human commensal bacterium was purified and characterized.
authors.affiliation: ISM2/BiosCiences UMR CNRS 6263, Interactions Moléculaires Microbiote - Muqueuse Intestinale, Service 342, Faculté des Sciences et Techniques de St Jérôme, Université Paul Cézanne Aix-Marseille III, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France.
authors.forename: E H
authors.initials: EH
authors.lastname: Crost
authors.forename: E H
authors.initials: EH
authors.lastname: Ajandouz
authors.forename: C
authors.initials: C
authors.lastname: Villard
authors.forename: P A
authors.initials: PA
authors.lastname: Geraert
authors.forename: A
authors.initials: A
authors.lastname: Puigserver
authors.forename: M
authors.initials: M
authors.lastname: Fons
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry; D001430:Bacteriocins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D002432:Cecum / Q000382:microbiology; D003016:Clostridium perfringens / Q000254:growth & development / Q000378:metabolism*; D005798:Genes, Bacterial; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007422:Intestines / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D051381:Rats; D045857:Ruminococcus / Q000378:metabolism*; D013440:Sulfides / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D001430:Bacteriocins; D013440:Sulfides; C001520:lanthionine; D000409:Alanine