水圈微生物驱动碳氮硫循环的代谢新机制

碳、氮、硫是生命体最主要的组成元素，具有复杂多样的赋存形态，其循环影响并决定地球环境复杂性和生物圈多样性。水圈微生物获取能量和营养以维持生命活动，这一过程产生和消耗有机物，介导元素赋存形态的改变，驱动生物地球化学循环。在研究团队前期工作基础上，拟揭示细胞层次感受碳氮水平并调控其代谢网络的分子机制，以及对生态链的反馈作用；解析滨海湿地微生物协同促进碳氮转化的耦联关系；探究近海海底沉积物中零价硫驱动的细菌碳氮硫代谢过程与机理；剖析固氮微生物驱动的碳氮硫耦合作用及甲烷生物合成新途径；揭示深海矿物热能驱动的微生物电子传递新机制，解析矿物能量转化效率与微生物功能代谢之间的关联规律；阐明胞外电子驱动的微生物碳氮固定及其生物被膜的形成机制。本研究拟在细胞-群落-典型生态等不同水平上揭示水圈微生物驱动生物地球化学循环的新途径、新机制，阐释水圈微生物在碳氮源和汇上的贡献，服务于“双碳”管理与决策。

Carbon (C), nitrogen (N), and sulfur (S) are the most important compositions of living organisms, with complex and diverse forms for function or storage, and their cycling influences and even determines the complexity of the Earth's environment and the diversity of biosphere. Hydrosphere microorganisms obtain energy and nutrients to sustain their life activities, and this process produces and consumes organic matter, which mediates the change of C, N and S forms and drives the global biogeochemical cycle. Based on progress made during the last few years on the understanding of the mechanism of element cycles of C, N, and S, driven by microorganisms in the hydrosphere, the research teams involved in this project will focus on several research topics, which will aim to: reveal the molecular mechanism on the environmental sensing of the different elements, the regulation on bacterial metabolic network, and the feedback effect on food chain; to dissect the coordinated actions of microorganisms on the coupled assimilation of carbon/nitrogen at the coast wetland; to study the process and mechanism of C/N/S metabolism driven by °S in bacteria in coast water sediments; to understand the coupling mechanism of C/N/S metabolic balance, the new methane biosynthetic pathway in diazotrophic bacteria; to uncover new mechanism of microbial electron transfer powered by mineral thermal energy in deep sea, and the rules of mineral energy governing microbial metabolism; to elucidate the mechanism on extracellular-electron-driven C/N fixation and biofilm formation in microorganisms. Through the above research work at multiple levels from cell to community to representative ecosystems, we intend to reveal the new pathways and mechanisms of the hydrosphere microorganisms driving the Earth's elemental cycle, and explain the contribution of hydrosphere microorganisms as carbon and nitrogen sources and sinks, so as to serve the management and decision-making of the “dual carbon" strategy.