title: Comparative study of two bacteriocins produced by representative indigenous soil bacteria.
abstract: The aim of this research work was to identify and characterized the bacteriocins produced by soil-associated bacteria. Bacillocin from Bacillus brevis Bb and pyocin from Pseudomonas aeruginosa Pa were found bioactive only against gram-positive bacteria tested. Maximum production of both the bacteriocins was observed at 32 degrees C in BHI medium. Production of both the bacteriocins started in the early exponential growth phase while the maximum production was observed during the stationary phase. Bacillocin Bb remained stable during 1-9 pH while pyocin Pa remained stable at pH 1-11. Both of the bacterocins were found resistant to high temperature (100 degrees C for 30 min), detergents (1% solutions of EDTA, Tween 20, Tween 80 and SDS) and organic solvents (1% solutions of Ethanol, Butanol, Methanol, Propanol, Chloroform, and Acetone). Activity of both was completely lost after proteinase K treatment suggesting their protein nature. Titre of bacillocin Bb was estimated to be 5280 AU/mL while the titre for pyocin Pa was calculated as 640 AU/mL. Both of the bacteriocins showed bacteriolytic mode of action against the indicator Bacillus strain BC31 and were found <10 KDa in their molecular mass.
authors: Department of Microbiology, University of Karachi, Karachi-75270, Pakistan.
authors: Farah
authors: F
authors: Saleem
authors: Samia
authors: S
authors: Ahmad
authors: Zobia
authors: Z
authors: Yaqoob
authors: Sheikh Ajaz
authors: SA
authors: Rasool
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000494:pharmacology; D001407:Bacillus / Q000254:growth & development / Q000378:metabolism*; D001430:Bacteriocins / Q000096:biosynthesis* / Q000494:pharmacology; D015169:Colony Count, Microbial; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000254:growth & development / Q000378:metabolism*; D012988:Soil Microbiology
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins