The role of dctP gene in regulating colonization, adhesion and pathogenicity of Vibrio alginolyticus strain HY9901

Vibriosis caused by Vibrio alginolyticus has severely affected the development of mariculture industry in recent decades. DctP, a tripartite ATP-independent periplasmic transporter solute-binding subunit, is thought to be one of the virulence factors in Vibrio. In this study, the results displayed no difference in morphological characteristics and growth between Delta dctP (dctP mutant strain) and WT (wild-type strain). Nevertheless, the ability of swarming motility, biofilm formation, ECPase formation, cell adhesion and colonized ability of Delta dctP significantly decreased compared to those of WT. The LD50 of Delta dctP significantly increased by 40-fold compared to that of WT. The transcriptome analysis demonstrated the deletion mutation of dctP could regulate the expression levels of 22 genes related to colonization, adhesion and pathogenicity in V. alginolyticus. The analysis of qRT-PCR showed the transcriptome data were reliable. These results reveal the effect of attenuated function of DctP on colonization, adherence and pathogenicity by controlling the expression of related gene.

Automated summary

This study found that attenuated function of DctP in V. alginolyticus leads to significant decreases in swarming motility, biofilm formation, ECPase formation, cell adhesion, and colonization ability, and a 40-fold increase in LD50 for the Delta dctP strain compared to the WT strain. Transcriptome analysis demonstrated that the deletion mutation of dctP could regulate the expression levels of 22 genes related to colonization, adhesion, and pathogenicity.