Effects of the critical gene luxS related to synthesis of AI-2 on biological characteristics of Vibrio parahaemolyticus

Abstract:

[Background] Vibrio parahaemolyticus is an important foodborne pathogen worldwide, which can cause gastroenteritis. Quorum sensing system LuxS/AI-2 can regulate the biological characteristics of bacteria, which provides a new pathway to study the dissemination mechanism and control techniques of V. parahaemolytics. [Objective] To study the effect of quorum sensing signaling molecule autoinducer-2 (AI-2) on the biological characteristics of V. parahaemolyticus Vp2009027 from seafood. [Methods] The critical gene luxS related to the synthesis of AI-2 was knocked out, and the luxS-knockout mutant of V. parahaemolytics Vp2009027 was constructed by homologous recombination with suicide plasmid. The effect of LuxS/AI-2 on the biological characteristics of V. parahaemolyticus was determined by comparing the growth, AI-2 activity, motility, biofilm formation ability, and antibiotic resistance between the wildtype strain and the mutant. [Results] The mutant was constructed successfully, which showed no significant difference in growth compared with the wildtype strain. The deletion of luxS led to the failure of AI-2 synthesis, increase in motility and biofilm formation ability, and weakening of tetracycline resistance. [Conclusion] luxS gene could regulate the biological characteristics of V. parahaemolyticus, which provided a reference for further research on the dissemination mechanism and development of control techniques of V. parahaemolyticus.