2G6I

Structure of rat nNOS heme domain (BH2-bound) in the reduced form

2G6I の概要

• エントリーDOI: 10.2210/pdb2g6i/pdb
• 分子名称: Nitric-oxide synthase, brain, ACETATE ION, ZINC ION, ... (7 entities in total)
• 機能のキーワード: nitric oxide synthase, heme protein, diatomic ligand, oxidoreductase
• 由来する生物種: Rattus norvegicus (Norway rat)
• 細胞内の位置: Cell membrane, sarcolemma; Peripheral membrane protein (By similarity): P29476
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 99469.88

構造登録者

Li, H.,Igarashi, J.,Jamal, J.,Yang, W.,Poulos, T.L. (登録日: 2006-02-24, 公開日: 2006-08-08, 最終更新日: 2023-08-30)

主引用文献

Li, H.,Igarashi, J.,Jamal, J.,Yang, W.,Poulos, T.L.
Structural studies of constitutive nitric oxide synthases with diatomic ligands bound.
J.Biol.Inorg.Chem., 11:753-768, 2006

PubMed Abstract: Crystal structures are reported for the endothelial nitric oxide synthase (eNOS)-arginine-CO ternary complex as well as the neuronal nitric oxide synthase (nNOS) heme domain complexed with L: -arginine and diatomic ligands, CO or NO, in the presence of the native cofactor, tetrahydrobiopterin, or its oxidized analogs, dihydrobiopterin and 4-aminobiopterin. The nature of the biopterin has no influence on the diatomic ligand binding. The binding geometries of diatomic ligands to nitric oxide synthase (NOS) follow the {MXY}(n) formalism developed from the inorganic diatomic-metal complexes. The structures reveal some subtle structural differences between eNOS and nNOS when CO is bound to the heme which correlate well with the differences in CO stretching frequencies observed by resonance Raman techniques. The detailed hydrogen-bonding geometries depicted in the active site of nNOS structures indicate that it is the ordered active-site water molecule rather than the substrate itself that would most likely serve as a direct proton donor to the diatomic ligands (CO, NO, as well as O(2)) bound to the heme. This has important implications for the oxygen activation mechanism critical to NOS catalysis.

PubMed: 16804678
DOI: 10.1007/s00775-006-0123-8

実験手法

X-RAY DIFFRACTION (1.9 Å)