Correlation between medium acidification and pathogenicity in environmental halophilic non-cholera vibrios

Aims: The metabolic characterization and pathogenicity of vibrios isolated from seafood were studied. Methods and Results: Strains of halophilic vibrios, grown in the presence o f 0.5% glucose, induced high medium acidification and were non-culturable a fter 24 h, while moderately acidifying strains were culturable, produced cy totoxins, and remained lethal when inoculated intraperitoneally in mice. Hi ghly acidifying strains failed to elicit pathogenicity in vivo and in vitro . Conclusions: The high acidification of the medium and the self-killing acti vity of NCVs might be considered a significant phenotypic marker of virulen ce and/or cytotoxicity. Significance and Impact of the Study: We suggest the medium acidification t est as possible screening method for pathogenic NCVs in food microbiology.