3EUB

Crystal Structure of Desulfo-Xanthine Oxidase with Xanthine

3EUB の概要

• エントリーDOI: 10.2210/pdb3eub/pdb
• 分子名称: Xanthine dehydrogenase/oxidase, FE2/S2 (INORGANIC) CLUSTER, FLAVIN-ADENINE DINUCLEOTIDE, ... (8 entities in total)
• 機能のキーワード: enzyme catalysis, desulfo, substrate orientation, xanthine, fad, flavoprotein, iron, iron-sulfur, metal-binding, molybdenum, nad, oxidoreductase, peroxisome
• 由来する生物種: Bos taurus (bovine); 詳細
• 細胞内の位置: Cytoplasm (By similarity): P80457 P80457 P80457
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 551294.16

構造登録者

Pauff, J.M.,Cao, H.,Hille, R. (登録日: 2008-10-09, 公開日: 2009-01-27, 最終更新日: 2023-09-06)

主引用文献

Pauff, J.M.,Cao, H.,Hille, R.
Substrate Orientation and Catalysis at the Molybdenum Site in Xanthine Oxidase: CRYSTAL STRUCTURES IN COMPLEX WITH XANTHINE AND LUMAZINE.
J.Biol.Chem., 284:8760-8767, 2009

PubMed Abstract: Xanthine oxidoreductase is a ubiquitous cytoplasmic protein that catalyzes the final two steps in purine catabolism. We have previously investigated the catalytic mechanism of the enzyme by rapid reaction kinetics and x-ray crystallography using the poor substrate 2-hydroxy-6-methylpurine, focusing our attention on the orientation of substrate in the active site and the role of Arg-880 in catalysis. Here we report additional crystal structures of as-isolated, functional xanthine oxidase in the course of reaction with the pterin substrate lumazine at 2.2 A resolution and of the nonfunctional desulfo form of the enzyme in complex with xanthine at 2.6 A resolution. In both cases the orientation of substrate is such that the pyrimidine subnucleus is oriented opposite to that seen with the slow substrate 2-hydroxy-6-methylpurine. The mechanistic implications as to how the ensemble of active site functional groups in the active site work to accelerate reaction rate are discussed.

PubMed: 19109252
DOI: 10.1074/jbc.M804517200

実験手法

X-RAY DIFFRACTION (2.6 Å)