Pseudomonas putida Strain FStm2 Isolated from Shark Skin: A Potential Source of Bacteriocin

• Published in: Probiotics and antimicrobial proteins 2013-09, Vol.5 (3), p.165-175
• Main Authors: Ahmad, Asmat, Hamid, Rahimi, Dada, Ayokunle Christopher, Usup, Gires
• Format: Article
• Language: English
• Subjects: Aeromonas hydrophila; alpha-amylase; ammonium sulfate; antibacterial properties; Applied Microbiology; Bacillus subtilis; bacteriocins; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; culture media; deoxyribonucleases; detergents; EDTA (chelating agent); Enterococcus faecalis; gel chromatography; glucose; heat stability; Microbiology; molecular weight; Nutrition; pathogens; peptidase K; polyacrylamide gel electrophoresis; polysorbates; Protein Science; Proteus mirabilis; Pseudomonas putida; ribonucleases; Salmonella Typhimurium; salt concentration; Serratia marcescens; sharks; sodium chloride; sodium dodecyl sulfate; temperature; tryptones; yeast extract
• ISSN: 1867-1306; 1867-1314
• DOI: 10.1007/s12602-013-9140-4

Bacteriocin-producing Pseudomonas putida strain FStm2 isolated from shark showed broad range of antibacterial activity against all pathogens tested except Bacillus subtilis ATCC11774, MRSA N32064, Proteus mirabilis ATCC12453, Enterococcus faecalis ATCC14506, Salmonella typhimurium ATCC51312, Salmonella mutan ATCC25175, and Aeromonas hydrophila Wbf314. Of the three growth media tested in this study, TSB was observed to support the bacteriocin activity the most. While the highest bacteriocin activity was observed for media supplemented with 1 % NaCl, there was an observed reduction in bacteriocin activity with increasing salt concentration. Although the least bacteriocin activity was observed for marine broth, addition of increasing amounts of tryptone, glucose, or yeast extract increased bacteriocin activity. This was, however, contrary to the effect observed when MgSO₄and MnSO₄were added as supplements. In the presence of α-amylase, lipase, DNase, and RNase, a positive effect on bacteriocin production was observed. Proteinase K strongly inhibited bacteriocin production. Furthermore, the bacteriocins produced were heat stable within the temperature range of 30–70 °C. Bacteriocin activity also was not affected within a wide pH range of 3–9. Exposure to detergents did not inhibit the activity of the bacteriocin at the concentrations tested. Instead, a positive effect on the relative activity of produced bacteriocin was observed as sodium dodecyl sulfate (SDS), EDTA, and Tween 20 at 1 % concentration all improved bacteriocin activity when the cell-free supernatant was tested against Serratia marcescens ATCC 13880. The bacteriocin was purified by ammonium sulfate precipitation and gel filtration on a Superdex-200 column. SDS-PAGE analysis of the partially purified bacteriocin revealed an apparent molecular weight of ~32 kDa.