Sci. Signal., 25 May 2010
Microbiology Cytosol, Salmonella, and pH
Stella M. Hurtley
Science, AAAS, Cambridge CB2 1LQ, UK
Salmonella and other bacterial pathogens grow inside animal host cells within intracellular vacuoles. The bacteria secrete effector proteins across the vacuole membrane, altering the host-cell physiology to the pathogens advantage. The secretion process involves a specialized secretory apparatus, the type III secretion system, whose assembly is triggered by the low pH within the host-cell vacuole. Now, Yu et al. (see the Perspective by Collier) have identified neutral pH as a physiological signal for effector translocation by intracellular Salmonella. The process involves the disassembly of a membrane-bound regulatory complex that is also found in other animal pathogens. Thus, Salmonella exploit the low pH of the vacuole as a signal to induce assembly of the secretion system, and then the neutral pH of the cytoplasm to trigger effector translocation.
Citation: S. M. Hurtley, Cytosol, Salmonella, and pH. Sci. Signal. 3, ec156 (2010).
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