A Vibrio Effector Protein Is an Inositol Phosphatase and Disrupts Host Cell Membrane Integrity

Mr. Blebby Vibrio parahaemolyticus , an important cause of contaminated fish-associated food poisoning, kills infected host cells within hours, using three sequential mechanisms: autophagy, cell rounding, and cell lysis. Broberg et al. (p. 1660 , published online 19 August) now describe a molecular mechanism of a bacterial effector protein that facilitates cell lysis by disrupting a target involved in regulating membrane dynamics and the actin cytoskeleton. The Vibrio effector, VPA0450, causes target cell membrane blebbing. The protein acts as an inositol polyphosphate 5-phosphatase and disrupts cytoskeletal binding sites on the inner surface of the plasma membrane of infected cells by hydrolyzing phosphatidylinositol 4,5-bisphosphate.