贵州阿哈湖水库沉积物中甲烷氧化菌分布与功能  

Distribution and functions of methanotrophs in the sediments of Aha Lake Reservoir,Guizhou Province

作　　者：赵若男 艾佳 李彦澄 王乐乐 李江[1,2] ZHAO Ruonan;AI Jia;LI Yancheng;WANG Lele;LI Jiang(Key Laboratory of Karst Georesources and Environment,Ministry of Education,College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,Guizhou,China;Guizhou Karst Environment Ecosystems Observation and Research Station,Ministry of Education,Guiyang 550025,Guizhou,China;Qiannan Ecological Environment Monitoring Center,Duyun 558013,Guizhou,China)

机构地区：[1]贵州大学资源与环境工程学院喀斯特地质资源与环境教育部重点实验室,贵州贵阳550025 [2]贵州喀斯特环境生态系统教育部野外科学观测研究站,贵州贵阳550025 [3]黔南生态环境监测中心,贵州都匀558013

出　　处：《微生物学报》2024年第3期809-825,共17页Acta Microbiologica Sinica

基　　金：国家自然科学基金(42267064);贵州省科技计划(黔科中引地[2022]4022);贵州省教育厅高等学校科技创新团队(黔教技[2023]056)。

摘　　要：甲烷氧化菌是一类能够以甲烷作为唯一碳源和能量维持生存的微生物,其活动与生态系统中物质循环及能量流动密切相关。【目的】了解阿哈湖水库沉积物中甲烷氧化菌群落结构及代谢功能。【方法】采用宏基因组技术对环湖沉积物和湖心沉积物进行研究。【结果】水库沉积物中主要的好氧甲烷氧化菌是甲基杆菌属(Methylobacter)(0.37%)和甲基单胞菌属(Methylomonas)(0.12%),主要的厌氧甲烷氧化菌是Candidatus_Methylomirabilis(0.12%),属于NC10门细菌中的亚硝酸盐反硝化型厌氧甲烷氧化菌,其中好氧甲烷氧化菌的pmoA基因为6.16×10^(7)copies/g,反硝化型厌氧甲烷氧化菌的16S rRNA基因为2.84×10^(7)copies/g。4种代谢的功能基因多样性表现为氮代谢>碳代谢>硫代谢>甲烷代谢,基于京都基因和基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)基因库进行注释得到6大类功能,发现18条与碳(包括甲烷)、氮、硫代谢有关的完整代谢途径。主坐标分析(principal coordinates analysis,PCoA)显示环湖沉积物与湖心沉积物之间的甲烷氧化菌种类和功能存在显著差异。影响甲烷氧化菌分布的主要环境因子为氧化还原电位、电导率和硫酸根。【结论】阿哈湖水库甲烷氧化菌以Ⅰ型好氧甲烷氧化菌为主,甲烷氧化菌群落代谢途径丰富,Ⅰ型和Ⅱ型甲烷氧化菌在对O2的适应性上有显著差异。相关研究可为湖泊水生态环境的保护和微生物资源的开发利用等方面提供一定的理论支撑。Methanotrophs can utilize methane as the only carbon source and energy,and they can survive and participate in material circulation and energy flow in ecosystems.[Objective]To unveil the structure and functions of methanotrophs community in the sediments from the Aha Lake Reservoir(referred to as the Reservoir),a typical karst lake reservoir in Guiyang City,Guizhou Province.[Methods]We used metagenomics to analyze the sediments collected from the edge and the center of the Reservoir.[Results]The dominant aerobic methanotrophs were Methylobacter(0.37%)and Methylomonas(0.12%),and the dominant anaerobic methanotrophs were Candidatus_Methylomirabilis(0.12%),being NC10 denitrifying anaerobic methanotrophs.The gene pmoA encoding particulate methane monooxygenase of aerobic methanotrophs had the relative abundance of 6.16×10^(7) copies/g and the 16S rRNA gene had the relative abundance of 2.84×10^(7) copies/g in denitrifying anaerobic methanotrophs.The diversity of four metabolic functional genes followed a trend of nitrogen metabolism>carbon metabolism>sulfur metabolism>methane metabolism.Kyoto encyclopedia of genes and genomes(KEGG)annotation revealed six functions and 18 complete pathways involving carbon(including methane),nitrogen,and sulfur metabolism.The results of principal coordinate analysis(PCoA)showed huge discrepancies in the distribution and functions of methanotrophs between sediments from the edge and the center of the Reservoir.Moreover,redox potential,conductivity,and sulfate were primary environmental factors affecting methanotroph distribution.[Conclusion]Type I aerobic methanotrophs dominated the Reservoir with abundant metabolic pathways.Types I and II methanotrophs exhibited huge discrepancies in terms of their adaptability to O2.All these fundings are expected to provide theoretical support for lake water environment conservation and microbial utilizationation.

关 键 词：甲烷氧化菌 阿哈湖 群落结构 功能基因 代谢途径 

分 类 号：X524[环境科学与工程—环境工程]