Olive Andrew J, Kenjale Roma, Espina Marianela, Moore David S, Picking Wendy L, Picking William D
Department of Molecular Biosciences, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA.
Infect Immun. 2007 May;75(5):2626-9. doi: 10.1128/IAI.01599-06. Epub 2007 Feb 12.
Shigella flexneri uses its type III secretion apparatus (TTSA) to deliver invasins into human cells. This TTSA possesses an external needle with IpaD at its tip. We now show that deoxycholate promotes the stable recruitment of IpaB to the needle tip without inducing a rapid burst of type III secretion. The maintenance of IpaB at the needle tip requires a stable association of IpaD with the Shigella surface. This is the first demonstration of a translocator protein being stably associated with the TTSA needle.
福氏志贺菌利用其三型分泌装置(TTSA)将侵袭素输送到人体细胞中。这种TTSA有一个外部针状结构,其尖端是IpaD。我们现在表明,脱氧胆酸盐可促进IpaB稳定募集到针状结构尖端,而不会引发三型分泌的快速爆发。IpaB在针状结构尖端的维持需要IpaD与志贺菌表面稳定结合。这是首次证明转运蛋白与TTSA针状结构稳定结合。