1PVD

CRYSTAL STRUCTURE OF THE THIAMIN DIPHOSPHATE DEPENDENT ENZYME PYRUVATE DECARBOXYLASE FROM THE YEAST SACCHAROMYCES CEREVISIAE AT 2.3 ANGSTROMS RESOLUTION

1PVD の概要

• エントリーDOI: 10.2210/pdb1pvd/pdb
• 分子名称: PYRUVATE DECARBOXYLASE, MAGNESIUM ION, THIAMINE DIPHOSPHATE, ... (4 entities in total)
• 機能のキーワード: lyase (carbon-carbon)
• 由来する生物種: Saccharomyces cerevisiae (baker's yeast)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 122381.53

構造登録者

Furey, W.,Arjunan, P. (登録日: 1995-04-20, 公開日: 1995-07-31, 最終更新日: 2024-02-21)

主引用文献

Arjunan, P.,Umland, T.,Dyda, F.,Swaminathan, S.,Furey, W.,Sax, M.,Farrenkopf, B.,Gao, Y.,Zhang, D.,Jordan, F.
Crystal structure of the thiamin diphosphate-dependent enzyme pyruvate decarboxylase from the yeast Saccharomyces cerevisiae at 2.3 A resolution.
J.Mol.Biol., 256:590-600, 1996

PubMed Abstract: The crystal structure of pyruvate decarboxylase (EC 4.1.1.1), a thiamin diphosphate-dependent enzyme isolated from Saccharomyces cerevisiae, has been determined and refined to a resolution of 2.3 A. Pyruvate decarboxylase is a homotetrameric enzyme which crystallizes with two subunits in an asymmetric unit. The structure has been refined by a combination of simulated annealing and restrained least squares to an R factor of 0.165 for 46,787 reflections. As in the corresponding enzyme from Saccharomyces uvarum, the homotetrameric holoenzyme assembly has approximate 222 symmetry. In addition to providing more accurate atomic parameters and certainty in the sequence assignments, the high resolution and extensive refinement resulted in the identification of several tightly bound water molecules in key structural positions. These water molecules have low temperature factors and make several hydrogen bonds with protein residues. There are six such water molecules in each cofactor binding site, and one of them is involved in coordination with the required magnesium ion. Another may be involved in the catalytic reaction mechanism. The refined model includes 1074 amino acid residues (two subunits), two thiamin diphosphate cofactors, two magnesium ions associated with cofactor binding and 440 water molecules. From the refined model we conclude that the resting state of the enzyme-cofactor complex is such that the cofactor is already deprotonated at the N4' position of the pyrimidine ring, and is poised to accept a proton from the C2 position of the thiazolium ring.

PubMed: 8604141
DOI: 10.1006/jmbi.1996.0111

実験手法

X-RAY DIFFRACTION (2.3 Å)