1AS7

STRUCTURE OF ALCALIGENES FAECALIS NITRITE REDUCTASE AT CRYO TEMPERATURE

1AS7 の概要

• エントリーDOI: 10.2210/pdb1as7/pdb
• 分子名称: NITRITE REDUCTASE, COPPER (II) ION (3 entities in total)
• 機能のキーワード: oxidoreductase, nitrite, copper, denitrification
• 由来する生物種: Alcaligenes faecalis
• 細胞内の位置: Periplasm: P38501
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 111572.94

構造登録者

Murphy, M.E.P.,Adman, E.T.,Turley, S. (登録日: 1997-08-13, 公開日: 1998-02-25, 最終更新日: 2024-05-22)

主引用文献

Murphy, M.E.,Turley, S.,Adman, E.T.
Structure of nitrite bound to copper-containing nitrite reductase from Alcaligenes faecalis. Mechanistic implications.
J.Biol.Chem., 272:28455-28460, 1997

PubMed Abstract: The structures of oxidized, reduced, nitrite-soaked oxidized and nitrite-soaked reduced nitrite reductase from Alcaligenes faecalis have been determined at 1.8-2.0 A resolution using data collected at -160 degrees C. The active site at cryogenic temperature, as at room temperature, contains a tetrahedral type II copper site liganded by three histidines and a water molecule. The solvent site is empty when crystals are reduced with ascorbate. A fully occupied oxygen-coordinate nitrite occupies the solvent site in crystals soaked in nitrite. Ascorbate-reduced crystals soaked in a glycerol-methanol solution and nitrite at -40 degrees C remain colorless at -160 degrees C but turn amber-brown when warmed, suggesting that NO is released. Nitrite is found at one-half occupancy. Five new solvent sites in the oxidized nitrite bound form exhibit defined but different occupancies in the other three forms. These results support a previously proposed mechanism by which nitrite is bound primarily by a single oxygen atom that is protonable, and after reduction and cleavage of that N-O bond, NO is released leaving the oxygen atom bound to the Cu site as hydroxide or water.

PubMed: 9353305
DOI: 10.1074/jbc.272.45.28455

実験手法

X-RAY DIFFRACTION (2 Å)