Purification, characterization, and biological effects of a second bacteriocin from Enterococcus faecalis ssp. liquefaciens S-48 and its mutant strain B-48-28. |
| |
Authors: | I López-Lara A Gálvez M Martínez-Bueno M Maqueda E Valdivia |
| |
Institution: | Departamento de Microbiología, Universidad de Granada, Facultad de Ciencias, Spain. |
| |
Abstract: | Enterococcus faecalis ssp. liquefaciens S-48 (producer of the peptide antibiotic AS-48) and its mutant B-48-28 (AS-48-) secrete the bacteriocin Bc-48. This substance has been purified to homogeneity from culture supernatants of strain B-48-28; it consists of a protein (80 kDa) stable from pH. 5.5 to 9.0 and sensitive to temperatures above 45 degrees C and to proteases. Its inhibitory spectrum is restricted to strains of Enterococcus faecalis. Bc-48 inhibits protein synthesis but does not affect amino acid uptake. A partial reduction of cell viability, together with autolysis, is also observed. Bc-48 differs from peptide AS-48 in both its molecular properties and mode of action. |
| |
Keywords: | |
|
|