A novel. bronectin type III module binding motif identified on C-terminus of Leptospira immunoglobulin-like protein, LigB
A novel. bronectin type III module binding motif identified on C-terminus of Leptospira immunoglobulin-like protein, LigB
复制标题
DOI：
10.1016/j.bbrc.2009.08.089
复制
发表时间：
2009-11-06
影响因子：
3.1
通讯作者：
Chang, Yung-Fu
中科院分区：
文献类型：
--
作者：
Lin, Yi-Pin;Greenwood, Alex;Chang, Yung-Fu
钩端螺旋体致病菌株的感染取决于病原体通过细胞外基质粘附于宿主细胞的能力，例如。连接蛋白（Fn）。以前，钩端螺旋体Lig蛋白的免疫球蛋白样结构域被认为是与Fn的N-末端结构域（NTD）和明胶结合结构域（GBD）结合的粘附素。在这项研究中，我们确定了钩端螺旋体粘附素LigB（LigBCtv）的C-末端上的另一个Fn结合基序，残基1708-1712包含具有β链和新生螺旋结构的序列LIPAD。该基序与第15个III型模块（15 F（3））结合（K-D = 10.70 μ M），结合（k（on）= 600 M-1 s（-1））和解离（k（off）= 0.0129 s（-1））速率常数代表了这种相互作用中的缓慢结合动力学。此外，用LigB（1706-1716）预处理MDCK细胞可将钩端螺旋体的结合阻断39%，表明LigB（1706-1716）在细胞粘附中发挥重要作用。这些数据表明问号钩端螺旋体LigB蛋白的LIPAD残基（LigB（1708-1712））在新的结合位点结合Fn的15 F（3），并且这种相互作用有助于粘附到宿主细胞。(C)2009 Elsevier Inc. All rights reserved.
Infection by pathogenic strains of Leptospira hinges on the pathogen's ability to adhere to host cells via extracellular matrix such as. bronectin (Fn). Previously, the immunoglobulin-like domains of Leptospira Lig proteins were recognized as adhesins binding to N-terminal domain (NTD) and gelatin binding domain (GBD) of Fn. In this study, we identified another Fn-binding motif on the C-terminus of the Leptospira adhesin LigB (LigBCtv), residues 1708-1712 containing sequence LIPAD with a beta-strand and nascent helical structure. This motif binds to 15th type III modules (15F(3)) (K-D = 10.70 mu M), and association (k(on) = 600 M-1 s(-1)) and dissociation (k(off) = 0.0129 s(-1)) rate constants represents a slow binding kinetics in this interaction. Moreover, pretreatment of MDCK cells with LigB(1706-1716) blocked the binding of Leptospira by 39%, demonstrating a significant role of LigB(1706-1716) in cellular adhesion. These data indicate that the LIPAD residues (LigB(1708-1712)) of the Leptospira interrogans LigB protein bind 15F(3) of Fn at a novel binding site, and this interaction contributes to adhesion to host cells. (C) 2009 Elsevier Inc. All rights reserved.