Isolation of a viable but non-culturable suppression mutant of Vibrio vulnificus: role of antioxidant enzymes in surviving stationary phase and low temperatures

ABSTRACT:   The viable but non-culturable (VBNC) suppression mutant was isolated. Suppression subtractive hybridization was used to identify differentially expressed genes among cDNA of the VBNC suppression mutant and the wild-type strain. RpoS-dependent catalase was highly expressed from the VBNC suppression mutant during oxidative stress in the stationary phase and at low temperatures. In experiments of H₂O₂ sensitivity, the VBNC suppression mutant showed a peroxide-resistant phenotype in the stationary phase and at low temperatures. These results suggest that VBNC suppression mutant cells use catalase for protection against oxidative stress in the stationary phase and at low temperatures.