Literature summary for 2.8.4.1 extracted from

Lyu, Z.; Chou, C.W.; Shi, H.; Wang, L.; Ghebreab, R.; Phillips, D.; Yan, Y.; Duin, E.C.; Whitman, W.B.
Assembly of methyl coenzyme M reductase in the methanogenic archaeon Methanococcus maripaludis (2018), J. Bacteriol., 200, e00746-17 .

Cloned(Commentary)

Cloned (Comment)	Organism
mcrBDCGA operon, genes Metok_0956, Metok_0960, and Metok_0957, recombinant expression of His-tagged MCRok from thermophile Methanothermococcus okinawensis (rMCRok) in mesophile Methanococcus maripaludis	Methanothermococcus okinawensis

General Stability

General Stability	Organism
enzyme MCR is notoriously unstable in its purified form	Methanothermococcus okinawensis

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Ni2+	contained in the prosthetic group cofactor coenzyme F430	Methanothermococcus okinawensis

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.
methyl-CoM + CoB	Methanothermococcus okinawensis	-	CoM-S-S-CoB + methane	-	?
methyl-CoM + CoB	Methanothermococcus okinawensis JCM 11175	-	CoM-S-S-CoB + methane	-	?
methyl-CoM + CoB	Methanothermococcus okinawensis IH1	-	CoM-S-S-CoB + methane	-	?
methyl-CoM + CoB	Methanothermococcus okinawensis DSM 14208	-	CoM-S-S-CoB + methane	-	?

Organism

Organism	UniProt	Comment	Textmining
Methanothermococcus okinawensis	F8AMU0 AND F8AMU4 AND F8AMU1	subunits alpha, beta, and gamma encoded by genes Metok_0956, Metok_0960, and Metok_0957	-
Methanothermococcus okinawensis DSM 14208	F8AMU0 AND F8AMU4 AND F8AMU1	subunits alpha, beta, and gamma encoded by genes Metok_0956, Metok_0960, and Metok_0957	-
Methanothermococcus okinawensis IH1	F8AMU0 AND F8AMU4 AND F8AMU1	subunits alpha, beta, and gamma encoded by genes Metok_0956, Metok_0960, and Metok_0957	-
Methanothermococcus okinawensis JCM 11175	F8AMU0 AND F8AMU4 AND F8AMU1	subunits alpha, beta, and gamma encoded by genes Metok_0956, Metok_0960, and Metok_0957	-

Purification (Commentary)

Purification (Comment)	Organism
recombinant His-tagged MCRok from Methanococcus maripaludis by nickel affinity chromatography, further purification by ion-exchange chromatography, and separation into two fraction, one with cofactor F430 and one without. Subunits of the native enzyme from Methanothermococcus maripaludis (or MCRmar) do not copurify with the rMCRok enzyme. The subunit stoichiometry of the rMCRok expressed in Methanococcus maripaludis is the same as the purified native enzyme, significant amounts of the coenzyme F430 are bound, and all of the posttranslational modifications of the native enzyme are present. Only negligible activity is observed for the purified rMCRok	Methanothermococcus okinawensis

Purification (Comment)

Organism

recombinant His-tagged MCRok from Methanococcus maripaludis by nickel affinity chromatography, further purification by ion-exchange chromatography, and separation into two fraction, one with cofactor F430 and one without. Subunits of the native enzyme from Methanothermococcus maripaludis (or MCRmar) do not copurify with the rMCRok enzyme. The subunit stoichiometry of the rMCRok expressed in Methanococcus maripaludis is the same as the purified native enzyme, significant amounts of the coenzyme F430 are bound, and all of the posttranslational modifications of the native enzyme are present. Only negligible activity is observed for the purified rMCRok

Methanothermococcus okinawensis

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
methyl-CoM + CoB	-	Methanothermococcus okinawensis	CoM-S-S-CoB + methane	-	?
methyl-CoM + CoB	-	Methanothermococcus okinawensis JCM 11175	CoM-S-S-CoB + methane	-	?
methyl-CoM + CoB	-	Methanothermococcus okinawensis IH1	CoM-S-S-CoB + methane	-	?
methyl-CoM + CoB	-	Methanothermococcus okinawensis DSM 14208	CoM-S-S-CoB + methane	-	?

Subunits

Subunits	Comment	Organism
heterotrimer	subunits alpha, beta, and gamma encoded by genes Metok_0956, Metok_0960, and Metok_0957	Methanothermococcus okinawensis

Synonyms

Synonyms	Comment	Organism
MCR	-	Methanothermococcus okinawensis
MCRok	-	Methanothermococcus okinawensis
methyl coenzyme M reductase	-	Methanothermococcus okinawensis
methyl-coenzyme M reductase	UniProt	Methanothermococcus okinawensis

Cofactor

Cofactor	Comment	Organism	Structure
F-430	coenzyme F430, MCR is a unique enzyme and of great intrinsic interest. The prosthetic group is the first known naturally occurring nickel tetrapyrrole, coenzyme F430. For the enzyme to be active, the metal must be in the Ni(I) oxidation state. Because the redox potential of the F430Ni(II)/F430Ni(I) couple is near -650 mV, the stability of the Ni(I) prosthetic group is critical for maintaining enzyme activity	Methanothermococcus okinawensis

General Information

General Information	Comment	Organism
metabolism	methyl coenzyme M reductase (MCR) is a complex enzyme that catalyzes the final step in biological methanogenesis. The methyl coenzyme M reductase (MCR) is central to all methanogenic pathways. Whether or not methane is formed from CO2, methyl groups, or acetate, the final step is catalyzed by MCR. In this reaction, methyl coenzyme M (CH3-S-CoM) is reduced by the thiol coenzyme B (HS-CoB) to form methane and the mixed disulfide (also called heterodisulfide, CoM-S-S-CoB). MCR is also involved in the anaerobic oxidation of methane	Methanothermococcus okinawensis
additional information	ordered assembly model for MCR expression	Methanothermococcus okinawensis
physiological function	methyl coenzyme M reductase (MCR) is a complex enzyme that catalyzes the final step in biological methanogenesis. The methyl coenzyme M reductase (MCR) is central to all methanogenic pathways. Whether or not methane is formed from CO2, methyl groups, or acetate, the final step is catalyzed by MCR. In this reaction, methyl coenzyme M (CH3-S-CoM) is reduced by the thiol coenzyme B (HS-CoB) to form methane and the mixed disulfide (also called heterodisulfide, CoM-S-S-CoB). MCR is also involved in the anaerobic oxidation of methane	Methanothermococcus okinawensis