ZntA maintains zinc and cadmium homeostasis and promotes oxidative stress resistance and virulence in Vibrio parahaemolyticus

Although metals are essential for life, they are toxic to bacteria in excessive amounts. Therefore, the maintenance of metal homeostasis is critical for bacterial physiology and pathogenesis. is a significant food-borne pathogen that mainly causes acute gastroenteritis in humans and acute hepatopancreatic necrosis disease in shrimp. Herein, we report that ZntA functions as a zinc (Zn) and cadmium (Cd) homeostasis mechanism and contributes to oxidative stress resistance and virulence in . is remarkably induced by Zn, copper, cobalt, nickel (Ni), and Cd, while ZntA promotes growth under excess Zn/Ni and Cd conditions via maintaining Zn and Cd homeostasis, respectively. The growth of Δ was inhibited under iron (Fe)-restricted conditions, and the inhibition was associated with Zn homeostasis disturbance. Ferrous iron supplementation improved the growth of Δ under excess Zn, Ni or Cd conditions. The resistance of Δ to H O -induced oxidative stress also decreased, and its virulence was attenuated in zebrafish models. Quantitative real-time PCR, mutagenesis, and β-galactosidase activity assays revealed that ZntR positively regulates expression by binding to its promoter. Collectively, the ZntR-regulated ZntA is crucial for Zn and Cd homeostasis and contributes to oxidative stress resistance and virulence in .