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2e7z
From Proteopedia
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Acetylene Hydratase from Pelobacter acetylenicus
Overview
The tungsten-iron-sulfur enzyme acetylene hydratase stands out from its class because it catalyzes a nonredox reaction, the hydration of acetylene to acetaldehyde. Sequence comparisons group the protein into the dimethyl sulfoxide reductase family, and it contains a bis-molybdopterin guanine dinucleotide-ligated tungsten atom and a cubane-type [4Fe:4S] cluster. The crystal structure of acetylene hydratase at 1.26 A now shows that the tungsten center binds a water molecule that is activated by an adjacent aspartate residue, enabling it to attack acetylene bound in a distinct, hydrophobic pocket. This mechanism requires a strong shift of pK(a) of the aspartate, caused by a nearby low-potential [4Fe:4S] cluster. To access this previously unrecognized W-Asp active site, the protein evolved a new substrate channel distant from where it is found in other molybdenum and tungsten enzymes.
About this Structure
2E7Z is a Single protein structure of sequence from Pelobacter acetylenicus with , , , , and as ligands. Active as Deleted entry, with EC number 4.2.1.71 Full crystallographic information is available from OCA.
Reference
Structure of the non-redox-active tungsten/[4Fe:4S] enzyme acetylene hydratase., Seiffert GB, Ullmann GM, Messerschmidt A, Schink B, Kroneck PM, Einsle O, Proc Natl Acad Sci U S A. 2007 Feb 27;104(9):3073-7. PMID:17360611
Page seeded by OCA on Thu Feb 21 17:07:04 2008
Categories: Deleted entry | Pelobacter acetylenicus | Single protein | Einsle, O. | Kroneck, P M.H. | Messerschmidt, A. | Seiffert, G B. | ACT | MGD | MPD | NA | SF4 | W | Dmso reductase family | Iron-sulfur-cluster | Tungstoprotein
