2uwj
Structure of the heterotrimeric complex which regulates type III secretion needle formationStructure of the heterotrimeric complex which regulates type III secretion needle formation
Structural highlights
FunctionPSCF_PSEAE Major component of the type III secretion needle structure. Required for cytotoxicity on macrophages.[1] [2] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedType III secretion systems (T3SS), found in several Gram-negative pathogens, are nanomachines involved in the transport of virulence effectors directly into the cytoplasm of target cells. T3SS are essentially composed of basal membrane-embedded ring-like structures and a hollow needle formed by a single polymerized protein. Within the bacterial cytoplasm, the T3SS needle protein requires two distinct chaperones for stabilization before its secretion, without which the entire T3SS is nonfunctional. The 2.0-A x-ray crystal structure of the PscE-PscF(55-85)-PscG heterotrimeric complex from Pseudomonas aeruginosa reveals that the C terminus of the needle protein PscF is engulfed within the hydrophobic groove of the tetratricopeptide-like molecule PscG, indicating that the macromolecular scaffold necessary to stabilize the T3SS needle is totally distinct from chaperoned complexes between pilus- or flagellum-forming molecules. Disruption of specific PscG-PscF interactions leads to impairment of bacterial cytotoxicity toward macrophages, indicating that this essential heterotrimer, which possesses homologs in a wide variety of pathogens, is a unique attractive target for the development of novel antibacterials. Structure of the heterotrimeric complex that regulates type III secretion needle formation.,Quinaud M, Ple S, Job V, Contreras-Martel C, Simorre JP, Attree I, Dessen A Proc Natl Acad Sci U S A. 2007 May 8;104(19):7803-8. Epub 2007 Apr 30. PMID:17470796[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
| ||||||||||||||||||