The quorum sensing regulator OpaR is a repressor of polar flagellum genes in Vibrio parahaemolyticus

J Microbiol. 2021 Jul;59(7):651-657. doi: 10.1007/s12275-021-0629-3. Epub 2021 Jun 1.


Vibrio parahaemolyticus possesses two types of flagella: a single polar flagellum (Pof) for swimming and the peritrichous lateral flagella (Laf) for swarming. Expression of Laf genes has previously been reported to be regulated by the quorum sensing (QS) regulators AphA and OpaR. In the present study, we showed that OpaR, the QS regulator at high cell density (HCD), acted as a negative regulator of swimming motility and the transcription of Pof genes in V. parahaemolyticus. OpaR bound to the promoter-proximal DNA regions of flgAMN, flgMN, and flgBCDEFGHIJ within the Pof gene loci to repress their transcription, whereas it negatively regulates the transcription of flgKL-flaC in an indirect manner. Thus, this work investigated how QS regulated the swimming motility via direct action of its master regulator OpaR on the transcription of Pof genes in V. parahaemolyticus.

Keywords: OpaR; Vibrio parahaemolyticus; polar flagellum; quorum sensing.

MeSH terms

  • Flagella / genetics*
  • Gene Expression Regulation, Bacterial*
  • Genes, Bacterial
  • Movement
  • Promoter Regions, Genetic
  • Quorum Sensing*
  • Regulatory Sequences, Nucleic Acid
  • Transcription Factors / metabolism*
  • Transcription, Genetic
  • Vibrio parahaemolyticus / genetics*
  • Vibrio parahaemolyticus / growth & development
  • Vibrio parahaemolyticus / physiology


  • OpaR protein, Vibrio parahaemolyticus
  • Transcription Factors