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Identification of an Enzyme Catalyzing the Conversion of Sulfoacetaldehyde to 2‑Mercaptoethanesulfonic Acid in Methanogens
journal contribution
posted on 2019-04-01, 00:00 authored by Robert H. WhiteCoenzyme M is an
essential coenzyme for the biochemical production
of methane. This Communication reports on the identification of an
enzyme catalyzing the last step in the biosynthesis of coenzyme M
in methanogens. Data presented here show that the enzyme, derived
from mj1681, catalyzes the conversion of the aldehyde functional group
of sulfoacetaldehyde into the thiol group of 2-mercaptoethanesulfonic
acid. Thus, a putative coenzyme M synthase (comF) has similarities
in sequence with both MJ0100 and MJ0099 proteins previously shown
to be involved in the biosynthesis of homocysteine [Allen, K. D.,
et al. (2015) Biochemistry 54, 3129–3132],
and both reactions likely proceed by the same mechanism. In the MJ0100-catalyzed
reaction, Rauch has proposed [Rauch, B. L. (2017) Biochemistry
56, 1051–1061] that MJ1526 and its homologues in other
methanogens likely supply the sulfane sulfur required for the reaction.