Mg2+ and ampicillin stimulons, and VP1649 and VPA0733 regulons

Vibrio parahaemolyticus RIMD 2210633 and its derivatives (VP1649- and VPA0733-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 1.4). Gene expression variations in VP1649 or VPA0733 mutant were compared with those in the wild-type strain. For indentification of ampicillin and Mg2+ regulons, RIMD 2210633 was grown in HI broth or HI broth supplemented with 400 microgram per milliliter ampicillin or 55 mM MgCl2, and cultured at 37 degrees with shaking at 200 rpm. Bacterial cells were harvested at the absorbance value at a wavelength of 600 nm was equal to 1.4.