title: Production, purification, sequencing and activity spectra of mutacins D-123.1 and F-59.1.
abstract: BACKGROUND
  The increase in bacterial resistance to antibiotics impels the development of new anti-bacterial substances. Mutacins (bacteriocins) are small antibacterial peptides produced by Streptococcus mutans showing activity against bacterial pathogens. The objective of the study was to produce and characterise additional mutacins in order to find new useful antibacterial substances.
  
  
  RESULTS
  Mutacin F-59.1 was produced in liquid media by S. mutans 59.1 while production of mutacin D-123.1 by S. mutans 123.1 was obtained in semi-solid media. Mutacins were purified by hydrophobic chromatography. The amino acid sequences of the mutacins were obtained by Edman degradation and their molecular mass was determined by mass spectrometry. Mutacin F-59.1 consists of 25 amino acids, containing the YGNGV consensus sequence of pediocin-like bacteriocins with a molecular mass calculated at 2719 Da. Mutacin D-123.1 has an identical molecular mass (2364 Da) with the same first 9 amino acids as mutacin I. Mutacins D-123.1 and F-59.1 have wide activity spectra inhibiting human and food-borne pathogens. The lantibiotic mutacin D-123.1 possesses a broader activity spectrum than mutacin F-59.1 against the bacterial strains tested.
  
  
  CONCLUSIONS
  Mutacin F-59.1 is the first pediocin-like bacteriocin identified and characterised that is produced by Streptococcus mutans. Mutacin D-123.1 appears to be identical to mutacin I previously identified in different strains of S. mutans.
authors.affiliation: Département de Biochimie Microbiologie et Bioinformatique, Faculté des Sciences et Génie, Université Laval, Québec (Québec), G1K 7P4, Canada. gui0me.nicolas@gmail.com
authors.forename: Guillaume G
authors.initials: GG
authors.lastname: Nicolas
authors.forename: Gisèle
authors.initials: G
authors.lastname: LaPointe
authors.forename: Marc C
authors.initials: MC
authors.lastname: Lavoie
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001430:Bacteriocins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000494:pharmacology*; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D013295:Streptococcus mutans / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins