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Publication Abstract from PubMed

Ni-dependent carbon monoxide dehydrogenases (Ni-CODHs) are a diverse family of enzymes that catalyze reversible CO:CO(2) oxidoreductase activity in acetogens, methanogens, and some CO-using bacteria. Crystallography of Ni-CODHs from CO-using bacteria and acetogens has revealed the overall fold of the Ni-CODH core and has suggested structures for the C cluster that mediates CO:CO(2) interconversion. Despite these advances, the mechanism of CO oxidation has remained elusive. Herein, we report the structure of a distinct class of Ni-CODH from methanogenic archaea: the alpha(2)epsilon(2) component from the alpha(8)beta(8)gamma(8)delta(8)epsilon(8) CODH/acetyl-CoA decarbonylase/synthase complex, an enzyme responsible for the majority of biogenic methane production on Earth. The structure of this Ni-CODH component provides support for a hitherto unobserved state in which both CO and H(2)O/OH(-) bind to the Ni and the exogenous FCII iron of the C cluster, respectively, and offers insight into the structures and functional roles of the epsilon-subunit and FeS domain not present in nonmethanogenic Ni-CODHs.

Structure of the alpha2epsilon2 Ni-dependent CO dehydrogenase component of the Methanosarcina barkeri acetyl-CoA decarbonylase/synthase complex.,Gong W, Hao B, Wei Z, Ferguson DJ Jr, Tallant T, Krzycki JA, Chan MK Proc Natl Acad Sci U S A. 2008 Jul 15;105(28):9558-63. Epub 2008 Jul 9. PMID:18621675^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.