Ferreira Thais Gonçalves, Moura Hercules, Barr John R, Pilotto Domingues Regina M C, Ferreira Eliane de Oliveira
Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, Brazil.
Centers for Disease Control and Prevention - CDC, Division of Laboratory Sciences, Atlanta, GA, USA.
Anaerobe. 2017 Jun;45:120-128. doi: 10.1016/j.anaerobe.2017.04.001. Epub 2017 Apr 21.
Clostridium difficile is a spore-forming anaerobic intestinal pathogen that causes Clostridium difficile infection (CDI). C. difficile is the leading cause of toxin-mediated nosocomial antibiotic-associated diarrhea. The pathogenesis of CDI is attributed to two major virulence factors, TcdA and TcdB toxins, that cause the symptomatic infection. C. difficile also expresses a number of key proteins, including cell wall proteins (CWPs). S-layer proteins (SLPs) are CWPs that form a paracrystalline surface array that coats the surface of the bacterium. SLPs have a role in C. difficile binding to the gastrointestinal tract, but their importance in virulence need to be better elucidated. Here, we describe bottom-up proteomics analysis of surface-enriched proteins fractions obtained through glycine extraction of five C. difficile clinical isolates from Brazil using gel-based and gel-free approaches. We were able to identify approximately 250 proteins for each strain, among them SlpA, Cwp2, Cwp6, CwpV and Cwp84. Identified CWPs presented different amino acid coverage, which might suggest differences in post-translational modifications. Proteomic analysis of SLPs from ribotype 133, agent of C. difficile outbreaks in Brazil, revealed unique proteins and provided additional information towards in depth characterization of the strains causing CDI in Brazil.
艰难梭菌是一种形成孢子的厌氧肠道病原体，可引起艰难梭菌感染（CDI）。艰难梭菌是毒素介导的医院内抗生素相关性腹泻的主要病因。CDI的发病机制归因于两种主要毒力因子，即导致症状性感染的TcdA和TcdB毒素。艰难梭菌还表达多种关键蛋白，包括细胞壁蛋白（CWP）。S层蛋白（SLP）是一种CWP，可形成覆盖细菌表面的准晶体表面阵列。SLP在艰难梭菌与胃肠道的结合中起作用，但其在毒力方面的重要性尚需进一步阐明。在此，我们描述了通过基于凝胶和无凝胶方法，对从巴西的五株艰难梭菌临床分离株进行甘氨酸提取所获得的表面富集蛋白组分进行的自下而上的蛋白质组学分析。我们能够为每个菌株鉴定出约250种蛋白质，其中包括SlpA、Cwp2、Cwp6、CwpV和Cwp84。鉴定出的CWP呈现出不同的氨基酸覆盖率，这可能表明翻译后修饰存在差异。对巴西艰难梭菌暴发流行株核糖体分型133的SLP进行蛋白质组学分析，揭示了独特的蛋白质，并为深入表征巴西引起CDI的菌株提供了更多信息。
