Production, purification, sequencing and activity spectra of mutacins D-123.1 and F-59.1
1 Département de Biochimie Microbiologie et Bioinformatique, Faculté des Sciences et Génie, Université Laval, Québec (Québec), G1K 7P4, Canada
2 Centre de Recherche en Sciences et Technologie du Lait (STELA), Institut des Nutraceutiques et des Aliments Fonctionnels (INAF), Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Québec (Québec), G1V 0A6, Canada
3 Département de Stomatologie, Faculté de Médecine Dentaire, Université de Montréal, Montréal (Québec), H3C 3J7, Canada
4 Department of Biological and Chemical Sciences, Faculty of Pure and Applied Sciences, The University of the West Indies, Cave Hill Campus, P.O. Box 64 Bridgetown, BB11000, Barbados
BMC Microbiology 2011, 11:69 doi:10.1186/1471-2180-11-69Published: 10 April 2011
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.
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.
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.