1cdo
From Proteopedia
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ALCOHOL DEHYDROGENASE (E.C.1.1.1.1) (EE ISOZYME) COMPLEXED WITH NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD), AND ZINC
Overview
The structural framework of cod liver alcohol dehydrogenase is similar to, that of horse and human alcohol dehydrogenases. In contrast, the substrate, pocket differs significantly, and main differences are located in three, loops. Nevertheless, the substrate pocket is hydrophobic like that of the, mammalian class I enzymes and has a similar topography in spite of many, main-chain and side-chain differences. The structural framework of alcohol, dehydrogenase is also present in a number of related enzymes like glucose, dehydrogenase and quinone oxidoreductase. These enzymes have completely, different substrate specificity, but also for these enzymes, the, corresponding loops of the substrate pocket have significantly different, structures. The domains of the two subunits in the crystals of the cod, enzyme further differ by a rotation of the catalytic domains by about 6, degrees. In one subunit, they close around the coenzyme similarly as in, coenzyme complexes of the horse enzyme, but form a more open cleft in the, other subunit, similar to the situation in coenzyme-free structures of the, horse enzyme. The proton relay system differs from the mammalian class I, alcohol dehydrogenases. His 51, which has been implicated in mammalian, enzymes to be important for proton transfer from the buried active site to, the surface is not present in the cod enzyme. A tyrosine in the, corresponding position is turned into the substrate pocket and a water, molecule occupies the same position in space as the His side chain, forming a shorter proton relay system.
About this Structure
1CDO is a Single protein structure of sequence from Gadus callarias with ZN and NAD as ligands. Active as Alcohol dehydrogenase, with EC number 1.1.1.1 Full crystallographic information is available from OCA.
Reference
Crystal structure of cod liver class I alcohol dehydrogenase: substrate pocket and structurally variable segments., Ramaswamy S, el Ahmad M, Danielsson O, Jornvall H, Eklund H, Protein Sci. 1996 Apr;5(4):663-71. PMID:8845755
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