Article

Role of Pseudomonas aeruginosa type III effectors in disease

Departments of Microbiology/Immunology and Medicine, Microbial Pathogenesis and Host Defense Program, Box 0654 UCSF, 513 Parnassus Ave, San Francisco, CA 94143, USA.
Current opinion in microbiology (Impact Factor: 5.9). 02/2009; 12(1):61-6. DOI: 10.1016/j.mib.2008.12.007
Source: PubMed

ABSTRACT

Pseudomonas aeruginosa uses a type III secretion system (T3SS) to directly inject four known effectors into host cells. ExoU is a potent cytotoxin with phospholipase A2 activity that causes rapid necrotic death in many cell types. The biological function of ExoY, an adenylate cyclase, remains incompletely defined. ExoS and ExoT are closely related bifunctional proteins with N-terminal GTPase activating protein (GAP) activity toward Rho family proteins and C-terminal ADP ribosylase (ADPRT) activity toward distinct and non-overlapping set of targets. While almost no strain encodes or secretes all four effectors, the commonly found combinations of ExoU/ExoT or ExoS/ExoT provides redundant and failsafe mechanisms to cause mucosal barrier injury, inhibit many arms of the innate immune response, and prevent wound repair.

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    • "The T3SS is a proteinaeous needle which translocates proteins, known as effectors, directly from the bacterial cytoplasm into the host cell (Hayes et al., 2010). The effectors secreted by the T3SS of P. aeruginosa – exoenzymes S, T, Y and U – are the major contributors to acute toxicity during the course of an infection (Barbieri & Sun, 2004; Engel & Balachandran, 2009; Hauser, 2009). The majority of P. aeruginosa isolates encode three of the four type III effectors, either STY or UTY (Feltman et al., 2001). "

    Full-text · Dataset · Oct 2014
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    • "The T3SS is a proteinaeous needle which translocates proteins, known as effectors, directly from the bacterial cytoplasm into the host cell (Hayes et al., 2010). The effectors secreted by the T3SS of P. aeruginosa – exoenzymes S, T, Y and U – are the major contributors to acute toxicity during the course of an infection (Barbieri & Sun, 2004; Engel & Balachandran, 2009; Hauser, 2009). The majority of P. aeruginosa isolates encode three of the four type III effectors, either STY or UTY (Feltman et al., 2001). "

    Full-text · Dataset · Sep 2014
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