1q5z | pdb_00001q5z
Crystal Structure of the C-terminal Actin Binding Domain of Salmonella Invasion Protein A (SipA)
Overview
Like many bacterial pathogens, Salmonella spp. use a type III secretion system to inject virulence proteins into host cells. The Salmonella invasion protein A (SipA) binds host actin, enhances its polymerization near adherent extracellular bacteria, and contributes to cytoskeletal rearrangements that internalize the pathogen. By combining x-ray crystallography of SipA with electron microscopy and image analysis of SipA-actin filaments, we show that SipA functions as a "molecular staple," in which a globular domain and two nonglobular "arms" mechanically stabilize the filament by tethering actin subunits in opposing strands. Deletion analysis of the tethering arms provides strong support for this model.
About this Structure
1Q5Z is a Single protein structure of sequence from Salmonella typhimurium. Full crystallographic information is available from OCA.
Reference
Salmonella SipA polymerizes actin by stapling filaments with nonglobular protein arms., Lilic M, Galkin VE, Orlova A, VanLoock MS, Egelman EH, Stebbins CE, Science. 2003 Sep 26;301(5641):1918-21. PMID:14512630 Page seeded by OCA on Sat May 3 05:54:26 2008
