Bacteriocin production by Pseudomonas spp.: spite and virulence

This study was done on Pseudomonas sp. to find out their antagonistic ability against other closely related strains through bacteriocin production. Pseudomonas strains were identified through higly selective medium Centrimide Agar (CA). Screening for bacteriocin production was carried out on three different media Lauria Bertani (LB), King’s B (KB) and Nutrient Broth Yeast (NBY), but the best results were obtained on NBY medium. Nine strains of Pseudomonas were found to produce anti-microbial activity, which inhibited the growth of related strains on agar medium. Among all the strains of Pseudomonas tested for bacteriocin production, strain 96-51 and AS1 were the most interesting strain on account of the number of strains inhibited and its weak cross resistance pattern when assayed against other strains. The bacteriocin protein was isolated from AS1, AS2, AP6 and 96-51. The bacteriocinogenic activity of isolated protein was done through bioassay. SDS-PAGE was also done to find out the molecular weight of the bacteriocin protein. The PGPR activity of the isolated strains was checked through pot experimentation.