外生菌根分泌耐热蛋白的特性及其对过量重金属的固持作用和机制

项目名称： 外生菌根分泌耐热蛋白的特性及其对过量重金属的固持作用和机制

项目编号： No.41271325

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 黄艺

作者单位： 北京大学

项目金额： 75万元

中文摘要： 根据本实验室在外生菌根真菌对过量重金属的细胞外抗性机理的研究成果，该项目提出，在重金属胁迫下，外生菌根真菌能够分泌对重金属具有高固持能力的类球囊霉素耐热蛋白的假设。拟通过特殊热提取方法提取菌根真菌和菌根分泌物中的耐热蛋白，利用分子生物学和蛋白免疫反应等技术手段，证明该提取物是与类球囊霉素相似的耐热蛋白。在此基础上，将测定分析该种耐热蛋白的分子量、氨基酸序列、蛋白质类型和对特异蛋白的免疫反应，以及过量重金属胁迫下该类蛋白中重金属的含量和分布，探索外生菌根真菌和菌根分泌物对重金属的固持能力和作用机制。研究菌根根际土壤中，土壤团聚体的形成、稳定性、团聚体种重金属固持量和形态与菌根分泌耐热蛋白的关系，探索菌根真菌通过影响土壤团聚体进而影响金属生物有效性，减少重金属生物毒害的机理。

中文关键词： 外生菌根；重金属；耐热蛋白；球囊霉素；分子生物学

英文摘要： Based on research results from this lab. on ecto-cell resistance mechanisms of ectomycorrhiza against heavy metal stress, the proposed study intended to provide sufficient evidences to approve a scientific hypothesis that, under heavy metal stress, ectomycorrhizal fungus may secrete glomalin-related protein, a kind of hot-resistant protein, to sequestrate heavy metal ions. Special extraction methods under high temperature will be installed to separate hot-resistant proteins from ectomycorrhizal fungus and their secretions, and further analysis will be done to determine the similarity of the extractions to glomalin-related protein by means of molecular biology and the protein's immunological response etc. The study will then test the characteristics of the extractions (molecular weight, sequence of ammonia acids, immunological responses to special proteins), and the content and distribution of heavy metal ions in the extractions under heavy metal stress. These studies will contribute to evaluate the mechanism and capacity of ectomycorrhizal fungus in sequestration of heavy metals through the secretions. Furthermore, characteristics of soil granular structure of the ecotomycorrhizal-rhizosphere will be tested on their formulation, stability, heavy metal contents and species in relation to the hot-resistant prot

英文关键词： Ectomycorrhiza；heavy metal；thermostable protein；glomalin；molecular biology