Publication Date:
2003-09-27
Description:
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.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lilic, Mirjana -- Galkin, Vitold E -- Orlova, Albina -- VanLoock, Margaret S -- Egelman, Edward H -- Stebbins, C Erec -- New York, N.Y. -- Science. 2003 Sep 26;301(5641):1918-21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Structural Microbiology, Rockefeller University, New York, NY 10021, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/14512630" target="_blank"〉PubMed〈/a〉
Keywords:
Actin Cytoskeleton/metabolism
;
Actins/*metabolism
;
Bacterial Proteins/*chemistry/genetics/*metabolism
;
Binding Sites
;
Crystallography, X-Ray
;
Image Processing, Computer-Assisted
;
Microfilament Proteins/*chemistry/genetics/*metabolism
;
Microscopy, Electron
;
Models, Molecular
;
Protein Binding
;
Protein Conformation
;
Protein Folding
;
Protein Structure, Secondary
;
Protein Structure, Tertiary
;
Recombinant Proteins/chemistry/metabolism
;
Salmonella typhimurium/chemistry/*metabolism
;
Sequence Deletion
;
Subtilisin/metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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