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Nep1样蛋白的膜相互作用机制

Mechanism of membrane interactions of Nep1-like proteins
课程网址: http://videolectures.net/biophysics2018_anderluh_membrane_interac...  
主讲教师: Gregor Anderluh
开课单位: 卢布尔雅那化学研究所
开课时间: 2018-07-09
课程语种: 英语
中文简介:
坏死和乙烯诱导肽1(Nep1)样蛋白(NLPs)是由多种植物病原菌分泌的毒力因子的大蛋白家族,可在细菌、真菌和卵菌中发现。在各种双子叶植物中,膜相互作用能够触发植物组织坏死和免疫相关反应。其细胞溶解机制的分子细节尚不十分清楚。最近,我们已经确定糖基肌醇磷酸神经酰胺(GIPC),植物相关的鞘脂,作为NLP与植物膜结合的靶分子。表面等离子体共振表明NLP蛋白可以通过毫摩尔亲和力结合糖氨基葡萄糖和甘露糖胺,它们通常作为GIPC中的末端糖存在。卵子菌无核腐霉与糖复合物中NLP蛋白的结构分析表明,糖结合诱导蛋白质发生结构变化,从而阐明金属离子配位对结合的重要性。此外,来自卵菌纲Hyaloperonospora arabidopsidis的NLP无毒代表性HaNLP3的结构表明,对细胞毒性起重要作用的蛋白质之间存在差异。总之,我们对有毒NLP蛋白对植物质膜的细胞溶解活性机制提供了重要的分子见解。
课程简介: Necrosis and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs) are large protein family of virulence factors that are secreted by various plant pathogens and can be found in bacteria, fungi and oomycetes. Upon membrane interactions they are able to trigger plant tissue necrosis and immunity-associated responses in various dicotyledonous plants. The molecular details of their cytolytic mechanism are not known in a great detail. Recently we have identified glycosyl inositol phospho ceramides (GIPC), plant-related sphingolipids, as a target molecule for NLPs binding to plant membranes. Surface plasmon resonance showed that NLP proteins can bind sugars glucosamine and mannosamine, which are often present as the terminal sugars in GIPCs, by millimolar affinity. Structural analysis of NLP protein from oomycete Pythium aphanidermatum in complex with the sugar have indicated structural changes in the protein induced by sugar binding and allow to elucidate the importance of the metal ion coordination for binding. Furthermore, the structure of the non-toxic representative of NLPs, HaNLP3, from oomycete Hyaloperonospora arabidopsidis indicated differences between the proteins that are important for the cytotoxicity. Collectively, we have provided important molecular insights into the mechanisms of cytolytic activity of toxic NLP proteins towards plant plasma membranes.  
关 键 词: 坏死和乙烯诱导肽1(Nep1)样蛋白(NLPs); 金属离子配位对结合; 蛋白质发生结构变化
课程来源: 视频讲座网
数据采集: 2021-11-05:zkj
最后编审: 2021-11-05:zkj
阅读次数: 120