1ED8

STRUCTURE OF E. COLI ALKALINE PHOSPHATASE INHIBITED BY THE INORGANIC PHOSPHATE AT 1.75A RESOLUTION

1ED8 の概要

• エントリーDOI: 10.2210/pdb1ed8/pdb
• 関連するPDBエントリー: 1ALK 1ED9
• 分子名称: ALKALINE PHOSPHATASE, ZINC ION, MAGNESIUM ION, ... (6 entities in total)
• 機能のキーワード: wild type, inhibited by phosphate, hydrolase
• 由来する生物種: Escherichia coli
• 細胞内の位置: Periplasm: P00634
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 95011.93

構造登録者

Stec, B.,Holtz, K.M.,Kantrowitz, E.R. (登録日: 2000-01-27, 公開日: 2000-09-20, 最終更新日: 2024-12-25)

主引用文献

Stec, B.,Holtz, K.M.,Kantrowitz, E.R.
A revised mechanism for the alkaline phosphatase reaction involving three metal ions.
J.Mol.Biol., 299:1303-1311, 2000

PubMed Abstract: Here, X-ray crystallography has been used to investigate the proposed double in-line displacement mechanism of Escherichia coli alkaline phosphatase in which two of the three active-site metal ions have a direct role in catalysis. Two new X-ray crystal structures of the wild-type enzyme in the absence and presence of inorganic phosphate have been refined at 1.75 A to final working R-factors of 15.4% and 16.4%, respectively. In the refinement of both structures, residues in the active sites were treated anisotropically. The ellipsoids resulting from the partial anisotropic refinement show a clear route for the binding and release of substrate/product. In addition, a direct comparison of the refined structures with and without phosphate reveal a strong correlation between the occupancy of the third metal-binding site and the conformation of the Ser102 nucleophile. These findings clarify two important and unresolved aspects of the previously proposed catalytic mechanism, how Ser102 is activated for nucleophilic attack and why a magnesium ion in the third metal site is required for catalysis. Analysis of these results suggest that three metal-ion assisted catalysis is a more accurate description of the mechanism of the alkaline phosphatase reaction. A revised mechanism for the catalytic reaction of alkaline phosphatase is proposed on the basis of the two new X-ray crystal structures reported.

PubMed: 10873454
DOI: 10.1006/jmbi.2000.3799

実験手法

X-RAY DIFFRACTION (1.75 Å)