IUBMB Enzyme Nomenclature


Accepted name: dihydromethanophenazine:CoB-CoM heterodisulfide reductase

Reaction: CoB + CoM + methanophenazine = CoM-S-S-CoB + dihydromethanophenazine

For diagram of reaction click here

Glossary: CoB = coenzyme B = N-(7-mercaptoheptanoyl)threonine 3-O-phosphate
CoB = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)
methanophenazine = 2-{[(6E,10E,14E)-3,7,11,15,19-pentamethylicosa-6,10,14,18-tetraen-1-yl]oxy}phenazine
CoM-S-S-CoB = CoB-CoM heterodisulfide = N-{7-[(2-sulfoethyl)dithio]heptanoyl}-O3-phospho-L-threonine

Other name(s): hdrDE (gene names); CoB–CoM heterodisulfide reductase (ambiguous); heterodisulfide reductase (ambiguous); coenzyme B:coenzyme M:methanophenazine oxidoreductase

Systematic name: CoB:CoM:methanophenazine oxidoreductase

Comments: This enzyme, found in methanogenic archaea that belong to the Methanosarcinales order, regenerates CoM and CoB after the action of EC, coenzyme-B sulfoethylthiotransferase. It is a membrane-bound enzyme that contains (per heterodimeric unit) two distinct b-type hemes and two [4Fe-4S] clusters. cf. EC, ferredoxin:CoB-CoM heterodisulfide reductase, EC, H2:CoB-CoM heterodisulfide,ferredoxin reductase, EC, formate:CoB-CoM heterodisulfide,ferredoxin reductase and EC, coenzyme F420:CoB-CoM heterodisulfide,ferredoxin reductase.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:


1. Hedderich, R., Berkessel, A. and Thauer, R.K. Purification and properties of heterodisulfide reductase from Methanobacterium thermoautotrophicum (strain Marburg). Eur. J. Biochem. 193 (1990) 255-261. [PMID: 2121478]

2. Abken, H.J., Tietze, M., Brodersen, J., Bäumer, S., Beifuss, U. and Deppenmeier, U. Isolation and characterization of methanophenazine and function of phenazines in membrane-bound electron transport of Methanosarcina mazei gol. J. Bacteriol. 180 (1998) 2027-2032. [PMID: 9555882]

3. Simianu, M., Murakami, E., Brewer, J.M. and Ragsdale, S.W. Purification and properties of the heme- and iron-sulfur-containing heterodisulfide reductase from Methanosarcina thermophila. Biochemistry 37 (1998) 10027-10039. [PMID: 9665708]

4. Murakami, E., Deppenmeier, U. and Ragsdale, S.W. Characterization of the intramolecular electron transfer pathway from 2-hydroxyphenazine to the heterodisulfide reductase from Methanosarcina thermophila. J. Biol. Chem. 276 (2001) 2432-2439. [PMID: 11034998]

[EC created 2003, modified 2017]

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