Production of bacteriocin by Bacteroides fragilis and partial characterization

The ability of Bacteroides fragilis strains, isolated from various sources, to produce bacteriocin was evaluated. All strains isolated from intestinal infections were producers in high levels and less susceptible to the other s. Strains from other origins were found to produce bacteriocin at a medium level and they were variably susceptible. Some properties of one bacterioc in produced by the Bact. fragilis 079298-3 strain were analysed, providing evidence of its protein nature, with stability over a wide range of pH and retained inhibitory activity after heating. This variability seems to sugge st that bacteriocin typing is a good method for this species.