1NDT

NITRITE REDUCTASE FROM ALCALIGENES XYLOSOXIDANS

1NDT の概要

• エントリーDOI: 10.2210/pdb1ndt/pdb
• 分子名称: PROTEIN (NITRITE REDUCTASE), COPPER (II) ION, CHLORIDE ION, ... (4 entities in total)
• 機能のキーワード: nitrite reductase, blue copper, oxidoreductase
• 由来する生物種: Achromobacter xylosoxidans
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 36208.18

構造登録者

Dodd, F.E.,Vanbeeumen, J.,Eady, R.R.,Hasnain, S.S. (登録日: 1998-10-28, 公開日: 1998-11-04, 最終更新日: 2023-08-16)

主引用文献

Dodd, F.E.,Van Beeumen, J.,Eady, R.R.,Hasnain, S.S.
X-ray structure of a blue-copper nitrite reductase in two crystal forms. The nature of the copper sites, mode of substrate binding and recognition by redox partner.
J.Mol.Biol., 282:369-382, 1998

PubMed Abstract: Denitrification is one of the main steps of the global nitrogen cycle that is sustained by prokaryotic organisms. Denitrifying bacteria use two entirely different enzymes in this process, one based on haem cd1 prosthetic groups and the other on type 1-type 2 Cu centres. Copper-containing nitrite reductases (NiRs) are sub-divided into blue and green NiRs, which are respectively thought to be redox partners of azurins and pseudo-azurins. Crystallographic structures of the blue nitrite reductase from Alcaligenes xylosoxidans (AxNiR) are presented in the oxidised hexagonal form and the substrate-bound orthorhombic form to 2.1 A and 2.8 A resolution, respectively. The complete amino acid sequence of AxNiR has been determined by conventional chemical analysis. A 3 A structure of AxNiR has been published where the modelling was based on the sequence of another blue NiR. The higher resolution of the hexagonal form together with the correct sequence allows a detailed comparison with the crystallographic structures of the green NiRs. There is a striking difference in the overall surface charge distribution between the two sub-groups, providing a neat structural explanation for their different reactivities to pseudoazurin or azurin and supporting the view that electron transfer proceeds via complex formation. A detailed examination of the type-1 Cu site, the site responsible for the colour, reveals several subtle differences, including a lateral displacement of 0.7 A for Smet. The structure of the type-2 Cu site, and changes that occur upon substrate binding are discussed in terms of the catalytic mechanism. The similarity of the type 2 Cu site to the catalytic Zn site in carbonic anhydrase and the catalytic Cu site of superoxide dismutase is re-examined in view of the high-resolution (2.1 A) structure.

PubMed: 9735294
DOI: 10.1006/jmbi.1998.2007

実験手法

X-RAY DIFFRACTION (2.1 Å)