1bw9
From Proteopedia
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PHENYLALANINE DEHYDROGENASE STRUCTURE IN TERNARY COMPLEX WITH NAD+ AND PHENYLPYRUVATE
Overview
The molecular structures of recombinant L-phenylalanine dehydrogenase from, Rhodococcus sp. M4 in two different inhibitory ternary complexes have been, determined by X-ray crystallographic analyses to high resolution. Both, structures show that L-phenylalanine dehydrogenase is a homodimeric enzyme, with each monomer composed of distinct globular N- and C-terminal domains, separated by a deep cleft containing the active site. The N-terminal, domain binds the amino acid substrate and contributes to the interactions, at the subunit:subunit interface. The C-terminal domain contains a typical, Rossmann fold and orients the dinucleotide. The dimer has overall, dimensions of approximately 82 A x 75 A x 75 A, with roughly 50 A, separating the two active sites. The structures described here, namely the, enzyme.NAD+.phenylpyruvate, and enzyme. NAD+.beta-phenylpropionate, species, represent the first models for any amino acid dehydrogenase in a, ternary complex. By analysis of the active-site interactions in these, models, along with the currently available kinetic data, a detailed, chemical mechanism has been proposed. This mechanism differs from those, proposed to date in that it accounts for the inability of the amino acid, dehydrogenases, in general, to function as hydroxy acid dehydrogenases.
About this Structure
1BW9 is a Protein complex structure of sequences from Rhodococcus sp. with K, NA, PO4, NAD, PPY, EDO and IPA as ligands. Active as Phenylalanine dehydrogenase, with EC number 1.4.1.20 Full crystallographic information is available from OCA.
Reference
Phenylalanine dehydrogenase from Rhodococcus sp. M4: high-resolution X-ray analyses of inhibitory ternary complexes reveal key features in the oxidative deamination mechanism., Vanhooke JL, Thoden JB, Brunhuber NM, Blanchard JS, Holden HM, Biochemistry. 1999 Feb 23;38(8):2326-39. PMID:10029526
Page seeded by OCA on Sun Nov 25 00:41:27 2007
