Isolation and preliminary characterization of bacteriocins produced by Vibrio vulnificus.
OBJECTIVE
The aim of this work was to isolate bacteriocins from the environment that would be effective in neutralizing Vibrio vulnificus in seafood.


RESULTS
Water samples from Wilmington (NC, USA) were plated to determine total viable counts and to isolate presumptive Vibrio spp. Isolates containing plasmids were checked for antimicrobial activity which was not due to lytic bacteriophage or small, non-specific molecules. Three bacteriocin producers were detected and their inhibitory spectra determined: IW1 inhibited few strains of V. vulnificus; BC1 inhibited several strains of V. vulnificus, V. cholerae and V. parahaemolyticus and BC2 inhibited all tested Vibrio spp., Plesiomonas shigelloides and Escherichia coli. Loss of inhibitory activity coincided with loss of the bacteriocinogenic plasmid. The bacteriocins were found to be between 1.3 and 9.0 kDa. IW1 was heat labile, while BC1 was moderately stable except at extreme temperatures. BC2 was very stable and maintained its activity when frozen, autoclaved or exposed to extreme pH values.


CONCLUSIONS
Bacteriocins have been isolated from environmental isolates of V. vulnificus and V. cholerae. BC2, with its broad spectrum and stability, may be useful in neutralizing V. vulnificus.


CONCLUSIONS
The results have significance in relation to reducing the occurrence of food poisoning caused by V. vulnificus.
Shehane
S D
SD
Department of Biological Sciences, University of North Carolina at Wilmington, Wilmington, NC 28403, USA.
Sizemore
R K
RK
D001430:Bacteriocins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D004798:Enzymes / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D009657:North Carolina; D010957:Plasmids / Q000302:isolation & purification; D017747:Seafood / Q000382:microbiology; D014733:Vibrio / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
D001430:Bacteriocins; D004798:Enzymes