Structure and Methylation of Coenzyme M (HSCH2CH2SO3)

Coenzyme M is a recently discovered cofactor which is involved in methyl transfer reactions in Methanobacterium. Information derived from infrared, proton NMR, and ultraviolet spectroscopy as well as from chemical tests and quantitative elemental analysis reveals that the coenzyme is 2,2′-dithiodiethanesulfonic acid. Verification of this structure resides in the comparison of authentic with chemically synthesized 2,2′-dithiodiethanesulfonic acid. Evidence indicates that an active form of this cofactor is 2-mercaptoethanesulfonic acid which is methylated producing 2-(methylthio) ethanesulfonic acid; this derivative is subsequently reductively demethylated, yielding methane.