State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, PR China.
Environ Sci Technol. 2011 Jan 15;45(2):508-13. doi: 10.1021/es102228v. Epub 2010 Dec 16.
To quantify the contribution of syntrophic acetate oxidation to thermophilic anaerobic methanogenesis under the stressed condition induced by acidification, the methanogenic conversion process of 100 mmol/L acetate was monitored simultaneously by using isotopic tracing and selective inhibition techniques, supplemented with the analysis of unculturable microorganisms. Both quantitative methods demonstrated that, in the presence of aceticlastic and hydrogenotrophic methanogens, a large percentage of methane (up to 89%) was initially derived from CO(2) reduction, indicating the predominant contribution of the syntrophic acetate oxidation pathway to acetate degradation at high acid concentrations. A temporal decrease of the fraction of hydrogenotrophic methanogenesis from more than 60% to less than 40% reflected the gradual prevalence of the aceticlastic methanogenesis pathway along with the reduction of acetate. This apparent discrimination of acetate methanization pathways highlighted the importance of the syntrophic acetate-oxidizing bacteria to initialize methanogenesis from high organic loadings.
为了量化在酸化诱导的应激条件下，协同乙酸氧化作用对嗜热厌氧产甲烷作用的贡献，采用同位素示踪和选择性抑制技术，同时辅以不可培养微生物分析，监测了 100mmol/L 乙酸的产甲烷转化过程。两种定量方法均表明，在乙酸营养型和氢营养型产甲烷菌存在的情况下，最初有很大一部分甲烷（高达 89%）来源于 CO2 还原，这表明在高酸浓度下，协同乙酸氧化途径对乙酸降解的贡献很大。氢营养型产甲烷作用的比例从最初的 60%以上逐渐降低到 40%以下，这反映了随着乙酸的减少，乙酸营养型产甲烷途径逐渐占主导地位。这种对乙酸甲烷化途径的明显区分突出了协同乙酸氧化细菌对从高有机负荷初始启动产甲烷作用的重要性。
