Characteristics of viable-but-nonculturable Vibrio parahaemolyticus induced by nutrient-deficiency at cold temperature

Vibrio parahaemolyticus has been consistently found to be involved in the food-borne disease outbreaks every year. Particularly, V. parahaemolyticus can be induced into a viable but nonculturable (VBNC) state under cold-starvation conditions. In this physiological state, V. parahaemolyticus losses its colony-forming ability and shows reduced metabolic activities. The subsequent failure of its detection may threaten public health-hygiene practices. Until now, evident information on physiological properties of VBNC V. parahaemolyticus and its underlying mechanism remains unclear and unorganized. Therefore, this review summarized survival behavior, persistence, and entry of pathogenic microorganisms into a VBNC state in response to various environmental conditions and discussed distinctive characteristics of VBNC cells. To survive under unfavorable environments, VBNC V. parahaemolyticus shows marked modifications in cell membrane composition, fatty acid synthesis, morphology, metabolism, gene expression, and capability of adhesion and virulence. These physiological modifications might be closely associated with an imbalance in maintaining essential biological processes within VBNC cells, thereby causing a decrease in cell membrane fluidity. To develop an efficient surveillance method and to prevent the recovery of VBNC cells in food, the induction of a VBNC state needs to be profoundly understood.