- Coenzyme M
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Coenzyme M is a coenzyme required for methyl-transfer reactions in the metabolism of methanogens.[1][2] The coenzyme is an anion with the formula HSCH2CH2SO−
3. It is named 2-mercaptoethanesulfonate and abbreviated HS–CoM. The cation is unimportant, but the sodium salt is most available. Mercaptoethanesulfonate contains both a thiol, which is the main site of reactivity, and a sulfonate group, which confers solubility in aqueous media.Biochemical role
The coenzyme is the C1 carrier in methanogenesis. It is converted to methyl coenzyme M, the thioether CH3SCH2CH2SO−
3, in the penultimate step to methane formation.[3] Coenzyme M reacts with coenzyme B, 7-thioheptanoylthreoninephosphate, to give a heterodisulfide, releasing methane:- CH3–S–CoM + HS–CoB → CH4 + CoB–S–S–CoM
This conversion is catalyzed by the enzyme methyl coenzyme M reductase, which contains cofactor F430 as the prosthetic group.
References
- ^ Balch WE, Wolfe RS (1979). "Specificity and biological distribution of coenzyme M (2-mercaptoethanesulfonic acid)". J. Bacteriol. 137 (1): 256–63. PMC 218444. PMID 104960. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=218444.
- ^ Taylor CD, Wolfe RS (10 August 1974). "Structure and methylation of coenzyme M(HSCH2CH2SO3)". J. Biol. Chem. 249 (15): 4879–85. PMID 4367810. http://www.jbc.org/cgi/reprint/249/15/4879.
- ^ Thauer RK (1998). "Biochemistry of Methanogenesis: a Tribute to Marjory Stephenson". Microbiology 144 (9): 2377–2406. doi:10.1099/00221287-144-9-2377. PMID 9782487. http://mic.sgmjournals.org/cgi/pmidlookup?view=long&pmid=9782487.
Enzyme cofactors Active forms TPP / ThDP (B1) · FMN, FAD (B2) · NAD+, NADH, NADP+, NADPH (B3) · Coenzyme A (B5) · PLP / P5P (B6) · Biotin (B7) · THFA / H4FA, DHFA / H2FA, MTHF (B9) · AdoCbl, MeCbl (B12) · Ascorbic Acid (C) · Phylloquinone (K1), Menaquinone (K2) · Coenzyme F420ATP · CTP · SAMe · PAPS · GSH · Coenzyme B · Cofactor F430 · Coenzyme M · Coenzyme Q · Heme / Haem (A, B, C, O) · Lipoic Acid · Methanofuran · Molybdopterin/Molybdenum cofactor · PQQ · THB / BH4 · THMPT / H4MPTBase forms M: NUT
cof, enz, met
noco, nuvi, sysi/epon, met
drug(A8/11/12)
Categories:- Coenzymes
- Thiols
- Sulfonates
- Biochemistry stubs
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