Vibrio parahaemolyticus RIMD 2210633 and its derivatives (VP0877-, VP1993- and VPA0388-single gene mutant) were grown in 2.5% (w/v) Bacto heart infusion (HI) broth (BD Biosciences, USA) at 37 degrees with shaking at 200 rpm. Bacterial cells were harvested at the mid-log phase (the absorbance value at a wavelength of 600 nm was equal to 0.8). Gene expression variations in VP0877, VP1993 or VPA0388 mutant were compared with those in the wild-type strain.