Formation of Methane from Acetate

Many methanogens like Methanosarcina sp. and Methanothrix thermophila ALS-1 produce methane from acetate (Ferry, 1992). 

This reaction releases the free energy enough for the biosynthesis of ATP. 

In the formation of methane from acetate, acetate is first changed to acetyl CoA and then methyl CoM is formed from this compound [reactions (6.5M6.7)] (Ragsdale et al., 1983a,b Grahame and Stadtman, 1987 Fischer and Thauer, 1988 Harder et al., 1989 Allen and Zinder, 1996). 

CH3C00P03H2+CoASH Phosphate acetytoansferase CH3COSC0A + H3P04 (6.6) 

CH3C0SC0A+C0MSH+H20 CODH-corrinoidenzyme complex CH3SCoM+ (6.7) 

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