副溶血弧菌Ⅲ型分泌系统vscH基因生物学功能分析OA北大核心

Vibrio parahaemolyticus is an important food-borne pathogen,and type Ⅲ secretion system 1(T3SS1)plays a major role in its pathogenic process.vscH gene is correlated with T3SS1,and its effects on the pathogenesis of Vibrio parahaemolyticus have not been clarified.To investigate the biological functions of the vscH gene in Vibrio parahaemolyticus.vscH gene deletion strains ΔvscH and vscH gene compensa-tion strain CΔvscH were constructed here based on POR-1 strains using the homologous recombination technology.The biological characteris-tics,such as biofilm formation and cytotoxicity,of the different strains were compared.The secretion of effector proteins and their transloca-tion in HeLa cells were detected by Western blot.The potential proteins interacting with vscH were identified by GST-Pull Down.The results showed that vscH deletion did not affect the growth of the mutant,compared with its parent strain;but it inhibited biofilm formation and re-duced toxicity to HeLa cells and CaCo-2 cells.Meanwhile,vscH deletion greatly reduced the secretion of effector proteins VopR and VopS,the extracellular needle structure protein Vsci,and it markedly suppressed the translocation of VopR and VopS in the HeLa cells.Moreover,there was a potential interaction between vscH and vscN with an ATPase located at T3SS1.The present study indicated that the vscH gene had effect on the biofilm formation of Vibrio parahaemolyticus,participated in T3SS1-mediated cytotoxicity,and was essential for the secretion and translocation of T3SS1 effector proteins.