1KQB

Structure of Nitroreductase from E. cloacae complex with inhibitor benzoate

1KQB の概要

• エントリーDOI: 10.2210/pdb1kqb/pdb
• 関連するPDBエントリー: 1KQC 1KQD
• 分子名称: OXYGEN-INSENSITIVE NAD(P)H NITROREDUCTASE, FLAVIN MONONUCLEOTIDE, BENZOIC ACID, ... (4 entities in total)
• 機能のキーワード: nitroreductase, flavin, benzoate, oxidoreductase
• 由来する生物種: Enterobacter cloacae
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 98242.57

構造登録者

Haynes, C.A.,Koder, R.L.,Miller, A.F.,Rodgers, D.W. (登録日: 2002-01-04, 公開日: 2002-02-13, 最終更新日: 2024-02-14)

主引用文献

Haynes, C.A.,Koder, R.L.,Miller, A.F.,Rodgers, D.W.
Structures of nitroreductase in three states: effects of inhibitor binding and reduction.
J.Biol.Chem., 277:11513-11520, 2002

PubMed Abstract: The crystal structure of the nitroreductase enzyme from Enterobacter cloacae has been determined for the oxidized form in separate complexes with benzoate and acetate inhibitors and for the two-electron reduced form. Nitroreductase is a member of a group of enzymes that reduce a broad range of nitroaromatic compounds and has potential uses in chemotherapy and bioremediation. The monomers of the nitroreductase dimer adopt an alpha+beta fold and together bind two flavin mononucleotide prosthetic groups at the dimer interface. In the oxidized enzyme, the flavin ring system adopts a strongly bent (16 degrees ) conformation, and the bend increases (25 degrees ) in the reduced form of the enzyme, roughly the conformation predicted for reduced flavin free in solution. Because free oxidized flavin is planar, the induced bend in the oxidized enzyme may favor reduction, and it may also account for the characteristic inability of the enzyme to stabilize the one electron-reduced semiquinone flavin, which is also planar. Both inhibitors bind over the pyrimidine and central rings of the flavin in partially overlapping sites. Comparison of the two inhibitor complexes shows that a portion of helix H6 can flex to accommodate the differently sized inhibitors suggesting a mechanism for accommodating varied substrates.

PubMed: 11805110
DOI: 10.1074/jbc.M111334200

実験手法

X-RAY DIFFRACTION (1.8 Å)