1mro
From Proteopedia
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METHYL-COENZYME M REDUCTASE
Overview
Methyl-coenzyme M reductase (MCR), the enzyme responsible for the, microbial formation of methane, is a 300-kilodalton protein organized as a, hexamer in an alpha2beta2gamma2 arrangement. The crystal structure of the, enzyme from Methanobacterium thermoautotrophicum, determined at 1.45, angstrom resolution for the inactive enzyme state MCRox1-silent, reveals, that two molecules of the nickel porphinoid coenzyme F430 are embedded, between the subunits alpha, alpha', beta, and gamma and alpha', alpha, beta', and gamma', forming two identical active sites. Each site is, accessible for the substrate methyl-coenzyme M through a narrow channel, locked after binding of the second substrate coenzyme B. Together with a, second structurally characterized enzyme state (MCRsilent) containing the, heterodisulfide of coenzymes M and B, a reaction mechanism is proposed, that uses a radical intermediate and a nickel organic compound.
About this Structure
1MRO is a Protein complex structure of sequences from Methanothermobacter thermautotrophicus with ZN, NA, F43, TP7, COM and GOL as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Crystal structure of methyl-coenzyme M reductase: the key enzyme of biological methane formation., Ermler U, Grabarse W, Shima S, Goubeaud M, Thauer RK, Science. 1997 Nov 21;278(5342):1457-62. PMID:9367957
Page seeded by OCA on Tue Dec 18 16:46:02 2007
Categories: Methanothermobacter thermautotrophicus | Protein complex | Ermler, U. | Grabarse, W. | COM | F43 | GOL | NA | TP7 | ZN | Biological methanogenesis | Ni-enzyme | Oxidoreductase
