Identification of fibronectin-binding proteins in Mycoplasma gallisepticum strain R
Identification of fibronectin-binding proteins in Mycoplasma gallisepticum strain R
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DOI：
10.1128/iai.74.3.1777-1785.2006
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发表时间：
2006-03-01
影响因子：
3.1
通讯作者：
Geary, SJ
中科院分区：
文献类型：
--
作者：
May, M;Papazisi, L;Geary, SJ
我们已经确定鸡毒支原体强毒株R-low能够与细胞外基质蛋白纤维连接蛋白结合。通过Western blotting和多肽测序发现鸡败血杆菌R-低蛋白提取物中存在纤维连接蛋白。鸡毒支原体R-High是R-low的弱化、高传代衍生物，但缺乏这种能力。肺炎支原体细胞黏附相关蛋白P65的同源物MGA_1199和肺炎支原体细胞骨架蛋白HMW3的同源物MGA_0928被鉴定为纤维连接蛋白结合蛋白。与已知纤维连接蛋白结合蛋白同源性最高的MGA_1199和MGA_0928区域的多肽与纤维连接蛋白的明胶/肝素结合区结合。MGA_1199和MGA_0928在R-HIGH中分别缺失和异常，说明其缺乏与纤维连接蛋白结合的能力。与肺炎支原体相同的是，MGA_1199(更名为PLPA)被证明是暴露在表面的，尽管缺乏典型的跨膜结构域。由于PLPA的拓扑结构和其结合肽与纤维连接蛋白之间的相互作用强度，我们认为PLPA在体内是一种纤维连接蛋白结合蛋白，可能具有非典型的跨膜区。
We have determined that virulent Mycoplasma gallisepticum strain R-low is capable of binding the extracellullar matrix protein fibronectin. Fibronectin was found to be present in M. gallisepticum R-low protein extracts by Western blotting and peptide sequencing. Mycoplasma gallisepticum R-high, the attenuated, high-passage derivative of R-low, is deficient in this ability. MGA_1199, the M. gallisepticum homologue of the cytadherence-associated protein P65 from Mycoplasma pneumoniae, and MGA_0928, the M. gallisepticum homologue of the M. pneumoniae cytoskeletal protein HMW3, were identified as fibronectin-binding proteins. Peptides from the regions of MGA_1199 and MGA_0928 exhibiting the highest degree of homology with known fibronectin-binding proteins were shown to bind the gelatin/heparin-binding domain of fibronectin. MGA_1199 and MGA_0928 were shown to be absent and aberrant, respectively, in R-high, explaining its lack of fibronectin-binding capability. Consistent with its M. pneumoniae counterpart, MGA_1199 (renamed PlpA) was demonstrated to be surface exposed, despite a lack of classical membrane-spanning domains. Due to its demonstrated topology and the strength of interaction between its binding peptide and fibronectin, we propose that PlpA functions as a fibronectin-binding protein in vivo and may possess atypical transmembrane domains.