Biophysical characterization of SipA, an actin‐binding protein from Salmonella enterica

FEBS Letters

Mitra, Kakoli¹  Zhou, Daoguo²  Galán, Jorge E.² 

[1] Department of Cell Biology, Yale University, New Haven, CT 06510, USA;Section of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, CT 06536, USA

关键词: Actin-binding protein;    Cytoskeleton;    Actin dynamics;    Salmonella enterica;    MALLS;    multiangle laser light scattering;    SAXS;    small angle X-ray scattering;    CD;    circular dichroism;    GST;    glutathione-S-transferase;   

DOI  :  10.1016/S0014-5793(00)02040-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

An essential step in the pathogenesis of Salmonella enterica infections is bacterial entry into non-phagocytic cells of the intestinal epithelium. Proteins injected by Salmonella into host cells stimulate cellular responses that lead to extensive actin cytoskeleton reorganization and subsequent bacterial uptake. One of these proteins, SipA, modulates actin dynamics by directly binding to F-actin. We have biophysically characterized a C-terminal fragment, SipA^446–684, which has previously been shown to retain activity. Our results show that SipA^446–684 exhibits an elongated shape with a predominantly helical conformation and predict the existence of a coiled-coil domain. We suggest that the protein is able to span two adjacent actin monomers in a filament and propose a model that is consistent with the observed effects of SipA^446–684 on actin dynamics and F-actin stability and morphology.

【 授权许可】

Unknown