氢营养型产甲烷代谢途径研究进展

Recent advances in hydrogenotrophic methanogenesis

产甲烷古菌是一类极端厌氧的古菌域微生物,可以利用CO2、甲醇、乙酸等简单化合物产甲烷并获得能量。目前能够培养的氢营养型(CO2/H2)产甲烷古菌的种类较多,而且在三类产甲烷代谢类型中,氢营养型产甲烷途径的产能效率最高,并具有多种模式的特殊能量利用系统。近年来,随着质谱、光谱和晶体技术的发展与运用,人们对产甲烷代谢途径的研究进一步深入,尤其是对氢营养型产甲烷途径的生化机制有了新的认识,揭示了产甲烷古菌在能量极限条件下独特、高效的能量利用模式。本文从能量储存、代谢途径、蛋白功能与催化机制等方面概述产甲烷古菌利用CO2/H2产甲烷的详细过程,并对产甲烷古菌代谢途径的研究方向与技术发展进行展望。

Methanogens are a group of extremely anaerobic microorganisms affiliated with the archaeal domain. They use simple compounds such as carbon dioxide, acetate and methyl compounds as substrate to grow. Hydrogenotrophic methanogens is the main type in all the cultured species. Among the three major methanogenic pathways, the hydrogenotrophic methanogenesis shows the highest energy productivity and includes a special energy metabolism system. In recent years, with the development and application of mass spectrum, spectroscopy and crystallization technology, the research on the methanogenic pathway has been further studied, especially in the biochemical mechanism of hydrogenotrophic methanogenesis, which revealing a unique and efficient way of energy conversation under extreme environment. Based on the massive research results, this review summarizes the details of hydrogenotrophic methanogenesis from the aspects of energy storage, metabolic pathways, enzyme structures and catalytic mechanism of enzymatic reactions. The prospect for the future research and technological development in the field of methanogenesis is also proposed in this review.