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1gyx
From Proteopedia
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THE CRYSTAL STRUCTURE OF YDCE, A 4-OXALOCROTONATE TAUTOMERASE HOMOLOGUE FROM ESCHERICHIA COLI, CONFIRMS THE STRUCTURAL BASIS FOR OLIGOMER DIVERSITY
Overview
The tautomerase superfamily consists of three major families represented, by 4-oxalocrotonate tautomerase (4-OT), 5-(carboxymethyl)-2-hydroxymuconate isomerase (CHMI), and macrophage, migration inhibitory factor (MIF). The members of this superfamily are, structurally homologous proteins constructed from a simple beta-alpha-beta, fold that share a key mechanistic feature; they use an amino-terminal, proline, which has an unusually low pK(a), as the general base in a, keto-enol tautomerization. Several new members of the 4-OT family have now, been identified using PSI-BLAST and categorized into five subfamilies on, the basis of multiple-sequence alignments and the conservation of key, catalytic and structural residues. The members of subfamily 5, which, includes a hypothetical protein designated YdcE from Escherichia coli, are, predicted not to form hexamers. The crystal structure of YdcE has been, determined to 1.35 A resolution and confirms that it is a dimer. In, addition, YdcE complexed with (E)-2-fluoro-p-hydroxycinnamate, identified, as a potent competitive inhibitor of this enzyme, as well as, N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid (HEPES) and benzoate, are also presented. These latter crystal structures reveal the location of, the active site and suggest a mechanism for the observed YdcE-catalyzed, tautomerization reaction. The dimeric arrangement of YdcE represents a new, structure in the 4-OT family and demonstrates structural diversity within, the 4-OT family not previously reported.
About this Structure
1GYX is a Single protein structure of sequence from Escherichia coli with and as ligands. Active as Phenylpyruvate tautomerase, with EC number 5.3.2.1 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
The crystal structure of YdcE, a 4-oxalocrotonate tautomerase homologue from Escherichia coli, confirms the structural basis for oligomer diversity., Almrud JJ, Kern AD, Wang SC, Czerwinski RM, Johnson WH Jr, Murzin AG, Hackert ML, Whitman CP, Biochemistry. 2002 Oct 8;41(40):12010-24. PMID:12356301
Page seeded by OCA on Sun Feb 3 09:44:08 2008
