Complexity of temperature dependence in methanogenic microbial environments

作者：Ralf Conrad · 发表于：Frontiers in Microbiology · 年份：2023 · DOI：10.3389/fmicb.2023.1232946 · 被引用次数：80 · 研究领域：Anaerobic Digestion and Biogas Production、Methane Hydrates and Related Phenomena、Atmospheric and Environmental Gas Dynamics

There is virtually no environmental process that is not dependent on temperature. This includes the microbial processes that result in the production of CH 4 , an important greenhouse gas. Microbial CH 4 production is the result of a combination of many different microorganisms and microbial processes, which together achieve the mineralization of organic matter to CO 2 and CH 4 . Temperature dependence applies to each individual step and each individual microbe. This review will discuss the different aspects of temperature dependence including temperature affecting the kinetics and thermodynamics of the various microbial processes, affecting the pathways of organic matter degradation and CH 4 production, and affecting the composition of the microbial communities involved. For example, it was found that increasing temperature results in a change of the methanogenic pathway with increasing contribution from mainly acetate to mainly H 2 /CO 2 as immediate CH 4 precursor, and with replacement of aceticlastic methanogenic archaea by thermophilic syntrophic acetate-oxidizing bacteria plus thermophilic hydrogenotrophic methanogenic archaea. This shift is consistent with reaction energetics, but it is not obligatory, since high temperature environments exist in which acetate is consumed by thermophilic aceticlastic archaea. Many studies have shown that CH 4 production rates increase with temperature displaying a temperature optimum and a characteristic apparent activation energy ( E ...