Aono Riyo, Emi Shogo, Okabe-Watanabe Kanako, Nariya Hirofumi, Matsunaga Nozomu, Hitsumoto Yasuo, Katayama Seiichi
Department of Material Science, School of Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan.
Department of Life Science, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama-shi, Okayama, 700-0005, Japan.
Anaerobe. 2023 Oct;83:102769. doi: 10.1016/j.anaerobe.2023.102769. Epub 2023 Aug 6.
Clostridium perfringens causes food poisoning and gas gangrene, a serious wound-associated infection. C. perfringens cells adhere to collagen via fibronectin (Fn). We investigated whether the peptidoglycan hydrolase of C. perfringens, i.e., autolysin (Acp), is implicated in Fn binding to C. perfringens cells.
This study used recombinant Acp fragments, human Fn and knockout mutants (C. perfringens 13 acp::erm and HN13 ΔfbpC ΔfbpD). Ligand blotting, Western blotting analysis, and complementation tests were performed. The Fn-binding activity of each mutant was evaluated by ELISA.
From an Fn-binding assay using recombinant Acp fragments, Fn was found to bind to the catalytic domain of Acp. In mutant cells lacking Acp, Fn binding was significantly decreased, but was restored by the complementation of the acp gene. There are three known kinds of Fn-binding proteins in C. perfringens: FbpC, FbpD, and glyceraldehyde-3-phosphate dehydrogenase. We found no difference in Fn-binding activity between the mutant cells lacking both FbpC and FbpD (SAK3 cells) and the wild-type cells, indicating that these Fn-binding proteins are not involved in Fn binding to C. perfringens cells.
We found that the Acp is an Fn-binding protein that acts as an Fn receptor on the surface of C. perfringens cells.
产气荚膜梭菌可引起食物中毒和气性坏疽，后者是一种与伤口相关的严重感染。产气荚膜梭菌细胞通过纤连蛋白（Fn）黏附于胶原蛋白。我们研究了产气荚膜梭菌的肽聚糖水解酶即自溶素（Acp）是否参与Fn与产气荚膜梭菌细胞的结合。
本研究使用重组Acp片段、人Fn和基因敲除突变体（产气荚膜梭菌13 acp::erm和HN13 ΔfbpC ΔfbpD）。进行了配体印迹、蛋白质印迹分析和互补试验。通过酶联免疫吸附测定（ELISA）评估每个突变体的Fn结合活性。
通过使用重组Acp片段的Fn结合试验发现，Fn可与Acp的催化结构域结合。在缺乏Acp的突变体细胞中，Fn结合显著降低，但通过acp基因的互补得以恢复。产气荚膜梭菌中有三种已知的Fn结合蛋白：FbpC、FbpD和甘油醛-3-磷酸脱氢酶。我们发现同时缺乏FbpC和FbpD的突变体细胞（SAK3细胞）与野生型细胞之间的Fn结合活性没有差异，这表明这些Fn结合蛋白不参与Fn与产气荚膜梭菌细胞的结合。
我们发现Acp是一种Fn结合蛋白，在产气荚膜梭菌细胞表面充当Fn受体。
