利用节杆菌B4胞外多糖研究多糖抑制铜绿假单胞菌生物膜形成的关键机制

项目名称： 利用节杆菌B4胞外多糖研究多糖抑制铜绿假单胞菌生物膜形成的关键机制

项目编号： No.31300045

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 李玉梅

作者单位： 济南大学

项目金额： 23万元

中文摘要： 针对多糖抑制铜绿假单胞菌生物膜形成作用机制尚不明确，极大限制了其医药开发与应用的研究现状。前期工作中我们发现节杆菌B4胞外多糖可高效抑制铜绿假单胞菌PAO1生物膜形成，抑制率达81%；它与同类报道多糖均具有半乳糖或甘露糖等组分，且它们都不杀菌而抑制生物膜形成，据此我们认为深入探索B4多糖抑制PAO1生物膜形成原因，将揭示多糖抑制铜绿假单胞菌生物膜形成的关键机制。本课题以B4多糖和PAO1为研究对象， 假设B4多糖抑制PAO1生物膜形成的作用靶位是其凝集素，拟采用红细胞凝集抑制试验、Western blotting研究B4多糖对PAO1凝集素的体外封闭作用，再利用框内缺失突变、荧光标记、共聚焦激光显微镜等技术研究B4多糖抑制PAO1凝集素缺失突变株、野生株生物膜体外形成的差异，阐明B4多糖靶向封闭凝集素是抑制PAO1生物膜形成的关键机制，为研究多糖抑制其它细菌生物膜形成作用机制提供理论参考。

中文关键词： 多糖；铜绿假单胞菌；抑制；生物膜；凝集素

英文摘要： The mechanism for polysaccharide inhibition of Pseudomonas aeruginosa biofilms is yet to be unclear, which limits the further development and application of these polysaccharides as antibiofilm drugs. In our previous study, an exopolysaccharide with the high antibiofilm activity against P. aeruginosa PAO1 was discovered from Arthrobacter sp.B4,whose inhibition rate was about 81%. Furthermore,it was observed that galactosyl and fucosyl were involved in the constituents of B4 and other antibiofilm polysaccharides, and their inhibitions of biofilms were achieved by non-biocidal modes of action. Thus elucidation of the cause for B4 polysaccharide of inhibition of biofilm will reveal the mechanism for polysaccharide inhibition of biofilm. In this study, B4 polysaccharide and P. aeruginosa PAO1 will be selected as the object of research, according to our previous results and other relative references, it will be hypothesized that polysaccharide inhibition of biofilm is achieved by targeting bacterial lectins. Firstly, Blocking of P. aeruginosa PAO1 lectins will be analyzed by hemagglutination inhibition test and western blotting. Secondly, the difference of biofilms between P. aeruginosa PAO1 wild stain and deletion mutants lacking lectin genes will be investigated in a static model of biofilm formation in vitro and

英文关键词： polysaccharide；Pseudomonas aeruginosa；inhibition；biofilm；lectin