1uhd
From Proteopedia
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Crystal structure of aspartate decarboxylase, pyruvoly group bound form
Overview
l-Aspartate alpha-decarboxylase (ADC), encoded by the panD gene, catalyzes, the conversion of l-aspartate into beta-alanine. In the microorganisms, beta-alanine is required for the synthesis of pantothenate (vitamin B(5)), which is the precursor of 4'-phosphopantetheine and coenzyme A. We have, determined the crystal structure of Helicobacter pylori ADC, a tetrameric, enzyme, in two forms: the apo structure at 2.0 A resolution and the, isoasparagine complex structure at 1.55 A resolution. All subunits of the, tetramer are self-processed at the Gly24-Ser25 linkage, producing the, smaller beta chain (residues 1-24) and the larger alpha chain (residues, 25-117). Each subunit contains nine beta-strands and three alpha-helices;, it is folded into the double-psi beta-barrel structure. In the apo, structure, the new amino terminus of the alpha chain, Ser25, is converted, into a pyruvoyl group. In the isoasparagine complex structure, the, substrate analog is covalently attached to the pyruvoyl group. This, structure represents the enzyme-substrate Schiff base intermediate that, was proposed to form prior to the decarboxylation step in the catalytic, cycle of ADC. Thus our study provides direct structural evidence for the, reaction mechanism of ADC.
About this Structure
1UHD is a Protein complex structure of sequences from Helicobacter pylori. Active as Aspartate 1-decarboxylase, with EC number 4.1.1.11 Full crystallographic information is available from OCA.
Reference
Crystal structure of the schiff base intermediate prior to decarboxylation in the catalytic cycle of aspartate alpha-decarboxylase., Lee BI, Suh SW, J Mol Biol. 2004 Jun 25;340(1):1-7. PMID:15184017
Page seeded by OCA on Wed Nov 21 04:07:40 2007
