长线状电活性微生物在地球元素循环和微生物群落互作中发挥重要作用。缺少可纯培养的长线状电活性微生物限制了对其生态功能及其作用机制的深入阐明。申请人所在团队前期从电子垃圾污染沉积物分离纯化了一株长线状变形赖氨酸芽孢杆菌新种Lysinibacillus varians GY32。该菌可双向胞外电子传递和加速沉积物中的硝酸盐还原。本项目拟以GY32为实验菌株在黑臭河流沉积物构建生物电化学系统，综合利用生物地球化学、生物电化学、环境微生物学、生物信息学等多学科分析手段，探究GY32对沉积物微生物群落的电子传递、结构与功能特点的影响，求证氮硫循环关键功能微生物能否借助GY32实现高效传递电子而耦合硝酸盐还原与硫氧化过程以调控氮硫循环，进而阐明GY32与氮硫循环关键功能微生物的协同工作机制。本项目有望发现长线状电活性微生物介导元素循环和微生物群落互作的新机制，为污染水环境的原位生物修复提供科学指导。

Filamentous electroactive microorganisms (EAM) play important roles in element cycling and in the syntrophy of microbial communities on the earth. The lack of purified culturable filamentous EAM has limited the understanding of the mechanism of their ecological function. Lysinibacillus varians GY32, which is a novel species of filamentous microorganisms, has been isolated and purified from electronic waste sediments by our group. GY32, which is capable of bidirectional electron transfer, can accelerate the nitrate reduction in sediments. In this project, GY32 will be used as the testing strain in bioelectrochemical systems which will be constructed in black-odors river sediments. This project intends to synthetically use multidisciplinary analysis methods from biogeochemistry, bioelectrochemistry, environmental microbiology and bioinformatics, to investigate the effect of GY32 on the electron transfer, the structure and the function of microbial communities in sediments, and to verify whether key functional microorganisms in the nitrogen and sulfur cycling couple nitrate reduction with sulfur oxidation for regulating the nitrogen and sulfur cycling by efficient electron transfer with the help of GY32. Thereby, the cooperation mechanism of GY32 and key functional microorganisms in the nitrogen and sulfur cycling will be demonstrated. The applicant presumes that the results of this project will provide novel understandings in the function and the mechanism of the filamentous EAM in element cycling and in the syntrophy of microbial communities, and will provide scientific guidance in the in-situ bioremediation of the contaminated water environment.