摘要：铜是常见的有毒污染物质，对生态环境有很大的危害。课题组在青年基金项目执行过程中发现，苜蓿中华根瘤菌CCNWSX0020对Cu2+具有较强耐受性，菌株通过Cop和Cue系统将细胞内Cu2+排出细胞，同时细胞表面的官能团也参与了铜的结合；在分子水平上，CutEC、CueR、CopB、CusC等基因也参与了细胞内Cu2+的平衡；菌株CCNWSX0020可提高共生植物天蓝苜蓿对Cu2+的吸收。这些研究结果分别发表在《Journal of Bacteriology》、《Bioresource Technology》和《农业环境科学学报》等刊物。但是根瘤菌促进共生固氮体系对铜污染土壤的生物修复作用机理是什么？共生固氮体系对根际土壤微生物群落结构组成和土壤理化性质等生态响应的影响如何？拟申报的连续资助项目将围绕这两个关键科学问题开展研究，以期揭示苜蓿中华根瘤菌及其共生固氮体系对铜污染土壤的生态修复

Abstract: Copper is toxic and harmful to the environment. Through the study supported by the State Natural Sciences Youth Fund Program , we found S. meliloti CCNWSX0020 had a strong resistance to Cd2+、Zn2+、Cu2+、Pb2+. Moreover, this strain could efflux Cu2+ to reduce Cu concentration in intracellular by Cop and Cue system. CutEC、CueR、CopB、CusC were predicted to involved into Cu homeostasis. In addition, S. meliloti CCNWSX0020 could improve the symbiotic plant Medicago lupulina absorb Cu2+. All these results have been published on <<Journal of Bacteriology>>, <<Bioresource Technology >>and <<Journal of Agro-Environment Science>>. But what is the promotion mechanism of bioremediation using the symbiosis under copper contaminated soil? How affect the ecological response of the copper-contaminated soil, including rhizosphere soil microbial community structure and soil physical chemical properties, induced by the symbiosis ? The continuous funding will focus on these two key scientific issues. The mechanism of bioremediation by Sinorhizobium-Medicago lupulina symbiosis under copper contaminated environment will be revealed finally.