Methane, an even more serious greenhouse gas than carbon dioxide, could be reduced effectively via anaerobic oxidation. According to standard Gibbs energies, it can be oxidized into carbon dioxide under anaerobic condition, when oxides e.g. SO42-, Mn4+, Fe3+, NO3- act as the electron acceptors. This paper focus on the mechanism, characteristics of methanotrophic bacteria and reaction condition of anaerobic oxidation driven by sulfate or nitrate. The problems and prospect of the research are also indicated. Reverse methanogenesis, acetogenesis and methylogenesis are three possible pathways in anaerobic oxidation driven by sulfate, whereas aerobic or anaerobic methane oxidation coupled to denitrification are probably the pathways when N(V serves as the electron acceptor. The concentrations of methane, SO42- or NO3- and organic content, as well as environmental conditions will dramatically affect anaerobic methane oxidation.%甲烷属于温室气体,厌氧氧化甲烷有效地减少了大气环境中甲烷的含量.依据吉布斯自由能变,以SO42-、Mn4+、Fe3+、NO3-等作为电子受体,厌氧条件下甲烷可以转化为CO2.重点阐述以SO42-和NO3-为电子受体时甲烷厌氧氧化的机理、反应发生的环境条件以及甲烷厌氧氧化菌的特点.针对目前研究存在的主要问题,提出了今后的发展方向.SO42-为电子受体时,甲烷厌氧氧化的可能途径包括:逆甲烷生成途径、乙酰生成途径以及甲基生成途径.甲烷的好氧或厌氧氧化协同反硝化是以NO3-为电子受体的甲烷氧化的可能途径.环境中的甲烷、硫酸盐或硝酸盐的浓度,有机质的数量,以及环境条件对甲烷的厌氧氧化有显著影响.
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