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1w85
From Proteopedia
THE CRYSTAL STRUCTURE OF PYRUVATE DEHYDROGENASE E1 BOUND TO THE PERIPHERAL SUBUNIT BINDING DOMAIN OF E2
Overview
Thiamine diphosphate (ThDP) is used as a cofactor in many key metabolic enzymes. We present evidence that the ThDPs in the two active sites of the E1 (EC 1.2.4.1) component of the pyruvate dehydrogenase complex communicate over a distance of 20 angstroms by reversibly shuttling a proton through an acidic tunnel in the protein. This "proton wire" permits the co-factors to serve reciprocally as general acid/base in catalysis and to switch the conformation of crucial active-site peptide loops. This synchronizes the progression of chemical events and can account for the oligomeric organization, conformational asymmetry, and "ping-pong" kinetic properties of E1 and other thiamine-dependent enzymes.
About this Structure
1W85 is a Protein complex structure of sequences from Geobacillus stearothermophilus. Full crystallographic information is available from OCA.
Reference
A molecular switch and proton wire synchronize the active sites in thiamine enzymes., Frank RA, Titman CM, Pratap JV, Luisi BF, Perham RN, Science. 2004 Oct 29;306(5697):872-6. PMID:15514159 Page seeded by OCA on Sat May 3 13:17:26 2008
