基于多组学的腾冲酸性温泉铁、砷氧化菌群协同除砷机制研究

Major sources of human-related arsenic pollution in China include mining and metallurgical wastewater. Both arsenite and arsenate, which are highly toxic inorganic arsenic forms, coexist in many acid mine drainage localities. Biomineralization is a promising approach for treatment of arsenic pollution in AMD. Acidophilic Fe-oxidizing microorganisms in the AMD catalyze rapid oxidation of ferrous iron to ferric iron, mediating the formation of secondary iron minerals, and arsenic gets naturally attenuated by adsorption and co-precipitation. In this process, microbial oxidation of arsenite to arsenate will be beneficial to the detoxification of arsenic in the AMD environment. Obtaining high-performing arsenic-removing microbial consortia capable of oxidizing ferrous iron as well as trivalent arsenic, clarifying the synergistic interactions among microbial species and elucidating their responses to environmental changes are the keys to achieving sustainable bioremediation of AMD arsenic pollution. These are also the research goals of this study. Tengchong acid hot spring is a treasure trove of iron metabolizing microorganisms and arsenic-transforming microbes which have great potential to remediate As-contaminated AMD. Here we propose to carry out bioremoval of arsenic by arsenic- and iron-oxidizing microbial consortia from acidic hot springs of Tengchong, and to have a deep understanding of structure and function of high-performing microbial consortia and also the synergistic interactions among microbial species using multi-omic approach, and to construct functional molecular ecological networks related to arsenic removal. The main aim of this study is to provide a basis for biofortification and developing bioremediation strategy.

人为的砷污染在我国的主要来源是采矿及冶金业废水。无机态的三价砷和五价砷共存于许多酸性矿山排水（AMD）中，无机砷有剧毒。利用生物矿化实现AMD中砷污染的治理十分有应用前景。嗜酸铁氧化菌驱动亚铁的快速氧化介导次生铁矿物形成，砷则通过次生矿物吸附和共沉淀被去除。在此过程中砷氧化菌将三价砷转化为五价砷有利于AMD环境的砷解毒。获得既可以氧化亚铁又可以氧化三价砷的高效除砷菌群，阐明微生物类群之间的协同作用机制及除砷过程中环境因素的影响，是实现AMD砷污染可持续生物修复的关键。这也正是本课题的研究目标。腾冲酸性温泉蕴藏着大量铁、砷代谢功能微生物，有修复AMD砷污染的应用潜力。本课题拟开展腾冲酸性温泉菌群除砷的研究，并通过宏基因组学、转录组学等手段深入揭示高效菌群的结构、功能及协同机制，构建砷去除相关的微生物分子生态网络，为微生物修复AMD砷污染时选择生物强化手段及修复策略提供依据。

人为的砷污染在我国的主要来源是采矿及冶金业废水。无机态的三价砷和五价砷共存于许多酸性矿山排水（AMD）中，无机砷有剧毒。利用生物矿化实现AMD中砷污染的治理十分有应用前景。嗜酸铁氧化菌驱动亚铁的快速氧化介导次生铁矿物形成，砷则通过次生矿物吸附和共沉淀被去除。在此过程中砷氧化菌将三价砷转化为五价砷有利于AMD环境的砷解毒。腾冲酸性温泉蕴藏着大量铁、砷代谢功能微生物，有修复AMD砷污染的应用潜力。有关亚铁氧化的微生物的研究十分丰富，而关于稻田等生态环境的砷氧化的微生物也有充分的研究，而有关酸性环境下的砷氧化微生物的研究则十分缺乏。在此背景下，本课题开展了腾冲酸性温泉菌群除砷的研究，并通过宏基因组学、全基因组学等手段系统揭示了腾冲温泉中砷抗性及砷转化微生物的种类、系统发育关系及分布情况，明确了不同来源的高效除砷菌群的共有、特有微生物及核心菌群，构建了砷去除相关功能微生物分子生态网络，揭示了主要微生物及参与砷去除的基因和代谢途径。本项目的研究可以为进一步开发利用腾冲温泉的砷氧化微生物资源和采用微生物修复AMD砷污染时选择生物强化手段及修复策略提供依据。