海洋沉积物中细菌DNA和RNA水平群落差异  

Differences Between DNA- and RNA-Based Bacterial Communities in Marine Sediments

作　　者：李明月 杨雨虹 米铁柱[1,2,3] 贺惠 甄毓[1,2,3] LI Ming-yue;YANG Yu-hong;MI Tie-zhu;HE Hui;ZHEN Yu(College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China;Laboratory for Marine Ecology and Environmental Science,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266071,China;Key Laboratory of Marine Environment and Ecology,Ministry of Education,Qingdao 266100,China;College of Marine Life Science,Ocean University of China,Qingdao 266003,China)

机构地区：[1]中国海洋大学环境科学与工程学院,青岛266100 [2]青岛海洋科学技术国家实验室海洋生态与环境科学功能实验室,青岛266071 [3]海洋环境与生态教育部重点实验室,青岛266100 [4]中国海洋大学海洋生命学院,青岛266003

出　　处：《环境科学》2020年第5期2485-2495,共11页Environmental Science

基　　金：国家重点研发计划项目(2017YFC1404402,2017YFC1404404);国家自然科学基金项目(41806131);中国博士后科学基金项目(2018M632722);青岛海洋科学与技术国家实验室鳌山科技创新计划项目(2016ASKJ02)。

摘　　要：海洋沉积物中的微生物在生物地球化学循环中具有重要作用.目前,细菌群落的研究多基于16S rRNA基因(DNA)展开,但DNA不仅包括活性微生物DNA也包括非活性微生物DNA,而RNA水平则可表征环境中具有活性的微生物种群.本研究采用荧光定量PCR和Illumina高通量测序技术,在DNA和RNA水平上研究了渤海和南黄海表层沉积物中细菌群落结构.结果表明,细菌DNA基因丰度比RNA基因丰度高1~2个数量级,DNA水平群落多样性高于RNA水平,二者群落结构差异显著.沉积物中的细菌具有活跃的化能异养、硫酸盐还原和硝化作用.基于16S rRNA基因的测序在探索微生物群落功能时可能会误判重要的功能微生物,总细菌群落中的"稀有生物圈"可能包含转录活跃者,发挥着重要的生物地球化学作用.总体而言,在分析来自稳定沉积环境的细菌群落结构时,基于16S rRNA的研究更能反映真实的生态状况.Microorganisms in marine sediments play crucial roles in biogeochemical processes. Currently, 16 S rRNA gene-based sequencing is popular for studying bacterial communities;however, the DNA used in analysis can include not only that from active microorganisms but also that from inactive microorganisms, while the RNA can represent active microorganisms and more recent activity in the environment;therefore, a study of the difference between the total bacterial community based on the 16 S rRNA gene and the active bacterial community based on 16 S rRNA will support a better understanding of bacterial community structure and function in marine sediments. In this study, the total and active bacterial community structures in surface sediments from the Bohai Sea and South Yellow Sea were investigated at DNA and RNA level using quantitative real-time polymerase chain reaction and Illumina high-throughput sequencing, respectively. The results show that the 16 S rRNA gene abundances of bacterial communities are 1-2 orders of magnitude higher than the transcript abundances. The total bacterial community is more diverse compared to the active bacterial community, and there are distinct differences between them. The bacteria in the sediments take part in active chemoheterotrophy, sulfate reduction, and nitrification. Moreover, 16 S rRNA gene-based sequencing misestimates some important functional microbiota when exploring bacterial community functions. The ‘rare biosphere’ in the total bacterial communities consists of actively transcriptional players, which could play key roles in biogeochemistry cycles. Overall, in the analysis of bacterial communities in marine sediments from a stable sedimentary environment, it is beneficial to use the 16 S rRNA sequencing to reflect the true ecological status.

关 键 词：沉积物 细菌群落 活性 DNA RNA 

分 类 号：X172[环境科学与工程—环境科学]