title: Mutacin H-29B is identical to mutacin II (J-T8).
abstract: BACKGROUND
  Streptococcus mutans produces bacteriocins named mutacins. Studies of mutacins have always been hampered by the difficulties in obtaining active liquid preparations of these substances. Some of them were found to be lantibiotics, defined as bacterial ribosomally synthesised lanthionine-containing peptides with antimicrobial activity. The goal of this study was to produce and characterize a new mutacin from S. mutans strain 29B, as it shows a promising activity spectrum against current human pathogens.
  
  
  RESULTS
  Mutacin H-29B, produced by S. mutans strain 29B, was purified by successive hydrophobic chromatography from a liquid preparation consisting of cheese whey permeate (6% w/v) supplemented with yeast extract (2%) and CaCO3 (1%). Edman degradation revealed 24 amino acids identical to those of mutacin II (also known as J-T8). The molecular mass of the purified peptide was evaluated at 3246.08 +/- 0.1 Da by MALDI-TOF MS.
  
  
  CONCLUSIONS
  A simple procedure for production and purification of mutacins along with its characterization is presented. Our results show that the amino acid sequence of mutacin H-29B is identical to the already known mutacin II (J-T8) over the first 24 residues. S. mutans strains of widely different origins may thus produce very similar bacteriocins.
authors.affiliation: Département de Biochimie et Microbiologie, Faculté des Sciences et Génie, Université Laval, Quebec, Quebec, G1K 7P4, Canada. guillaume.nicolas.1@ulaval.ca
authors.forename: Guillaume
authors.initials: G
authors.lastname: Nicolas
authors.forename: Hélène
authors.initials: H
authors.lastname: Morency
authors.forename: Gisèle
authors.initials: G
authors.lastname: LaPointe
authors.forename: Marc C
authors.initials: MC
authors.lastname: Lavoie
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D001430:Bacteriocins / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013295:Streptococcus mutans / Q000145:classification / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; C069066:mutacin II