Entry of Vibrio cincinnatiensis into viable but nonculturable state and its resuscitation.

AIMS

The aim was to characterize the viable but nonculturable (VBNC) state of Vibrio cincinnatiensis and its resuscitation.

METHODS AND RESULTS

Vibrio cincinnatiensis VIB287 was cultured in sterilized seawater microcosms at 4 degrees C. Plate counts, direct viable counts and total counts were used. A large population of the V. cincinnatiensis became nonculturable after approx. 50 day at 4 degrees C. Electron microscopy revealed that the VBNC cells changed from rod to coccoid and decreased in size. Resuscitation of VBNC cells was achieved by temperature upshift in nutrition of yeast extract and peptone by addition of catalase or compound vitamin B. The VBNC and resuscitative cells were intraperitoneally injected into zebra fish separately. No death was observed in the group inoculated with the VBNC cells.

CONCLUSIONS

Vibrio cincinnatiensis VIB287 could enter VBNC state in adverse environments. Resuscitation of VBNC cells occurred by addition of compound vitamin B or catalase to VBNC cells containing nutrient. The resuscitative cells might retain their pathogenicity.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study confirmed that V. cincinnatiensis could enter into VBNC state in seawater at low temperature and resuscitated. The resuscitative cells retained their pathogenicity, which may be important in future studies of ecology of V. cincinnatiensis.