The Impact of Vp-porin, an Outer Membrane Protein, on the Biological Characteristics and Virulence of Vibrio parahaemolyticus

Porins are crucial proteins located in the outer membrane that directly influence antimicrobial resistance mechanisms and virulence in bacteria. In this study, a porin gene (Vp-porin) was cloned in V. parahaemolyticus, and the function of Vp-porin on biological characteristics and virulence was investigated. The results of sequence analysis showed that Vp-porin is highly conserved in Vibrio spp. and the predicted 3D structure showed it could form a transmembrane channel with 20 β barrel. Membrane permeabilization provides evidence that membrane integrity of ∆Vp-porin was damaged and the sensitivity to tetracycline, polymyxin B, rifampicin and cephalothin of ∆Vp-porin obvious increased. In addition, loss of Vp-porin damaged motility due to down-regulated flagellar synthesis. Besides, ∆Vp-porin exhibited attenuated cytotoxicity to Tetra-hymena. The relative survival rate of Tetrahymena infection with ∆Vp-porin was 86%, which is much high than that with WT (49%). Take together, Vp-porin in V. parahaemolyticus plays various roles in biological characteristics in membrane integrity, antimicrobial resistance and motility, and contributes to virulence.