Methanogenesis and Methylotrophy: Pathways and Mechanisms

This lecture covers the biochemical pathways of methanogenesis and methylotrophy, focusing on the three main pathways of methanogenesis: hydrogenotrophic, methylotrophic, and aceticlastic. The instructor explains how each pathway utilizes different substrates, such as CO2, methanol, and acetate, to produce methane. The lecture details the enzymatic processes involved, including the roles of methyl-CoM and methyl reductase complexes in the reduction of substrates to methane. Additionally, the energy generation mechanisms associated with these pathways are discussed, highlighting the importance of proton motive force in ATP production. The lecture transitions to methylotrophy, explaining how methylotrophs oxidize C1 compounds like methane and methanol, and the differences between type I and type II methylotrophs. The instructor also addresses anaerobic oxidation of methane (AOM) and its significance in carbon cycling, emphasizing the symbiotic relationships between methanotrophic archaea and sulfate-reducing bacteria. The session concludes with an overview of fermentation processes and their relevance in biofuel production.