Bacteriostatic effects of benzyl isothiocyanate on Vibrio parahaemolyticus: Transcriptomic analysis and morphological verification
We investigated antibacterial activities of benzyl isothiocyanate (BITC) against V. parahaemolyticus by transcriptomic analysis and morphological verification. Treatment with 1/8MIC BITC resulted in 234 up-regulated genes and 273 down-regulated genes. In V. parahaemolyticus, we selected six genes that were significantly down-regulated from the transcriptome results and verified them using quantitative Real-time Polymerase Chain Reaction (qRT-PCR). The verification experiments indicated that the relative expressions of the six virulence genes VP0820, VP0548, VP2233, VPA2362, fliA and fliG were only 31.0%, 31.1%, 55.8%, 57.0%, 75.3%, and 79.9% of the control group, respectively. Among them, VP2233, fliA and fliG are related to flagella, and VP2362 can regulate a protein related to biofilm formation. From the morphological aspect, we verified that under the action of 1/8 MIC BITC, the swimming diffusion diameter of V. parahaemolyticus was significantly reduced by 14.9%, and biofilm formation was significantly inhibited. These results indicate that 1/8 MIC BITC can reduce the pathogenicity of V. parahaemolyticus by inhibiting virulence gene expression related to flagella and biofilm, which is helpful for further understanding of bacteriostatic mechanism of BITC on V. parahaemolyticus and other food-borne pathogens. Overall design: Analysis of genetic changes in Vibrio parahaemolyticus after BITC addition