6BZ5

Structure and mechanism of salicylate hydroxylase from Pseudomonas putida G7

6BZ5 の概要

• エントリーDOI: 10.2210/pdb6bz5/pdb
• 分子名称: Salicylate hydroxylase, IODIDE ION, GLYCEROL, ... (6 entities in total)
• 機能のキーワード: aromatic hydrocarbons catabolism, salicylate hydroxylase, flavoprotein, oxidoreductase
• 由来する生物種: Pseudomonas putida (Arthrobacter siderocapsulatus)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 101360.44

構造登録者

Nagem, R.A.P.,Costa, D.M.A. (登録日: 2017-12-22, 公開日: 2018-12-26, 最終更新日: 2024-03-13)

主引用文献

Costa, D.M.A.,Gomez, S.V.,de Araujo, S.S.,Pereira, M.S.,Alves, R.B.,Favaro, D.C.,Hengge, A.C.,Nagem, R.A.P.,Brandao, T.A.S.
Catalytic mechanism for the conversion of salicylate into catechol by the flavin-dependent monooxygenase salicylate hydroxylase.
Int.J.Biol.Macromol., 129:588-600, 2019

PubMed Abstract: Salicylate hydroxylase (NahG) is a flavin-dependent monooxygenase that catalyzes the decarboxylative hydroxylation of salicylate into catechol in the naphthalene degradation pathway in Pseudomonas putida G7. We explored the mechanism of action of this enzyme in detail using a combination of structural and biophysical methods. NahG shares many structural and mechanistic features with other versatile flavin-dependent monooxygenases, with potential biocatalytic applications. The crystal structure at 2.0 Å resolution for the apo form of NahG adds a new snapshot preceding the FAD binding in flavin-dependent monooxygenases. The k/K for the salicylate reaction catalyzed by the holo form is >10 M s at pH 8.5 and 25 °C. Hammett plots for K and k using substituted salicylates indicate change in rate-limiting step. Electron-donating groups favor the hydroxylation of salicylate by a peroxyflavin to yield a Wheland-like intermediate, whereas the decarboxylation of this intermediate is faster for electron-withdrawing groups. The mechanism is supported by structural data and kinetic studies at different pHs. The salicylate carboxyl group lies near a hydrophobic region that aids decarboxylation. A conserved histidine residue is proposed to assist the reaction by general base/general acid catalysis.

PubMed: 30703421
DOI: 10.1016/j.ijbiomac.2019.01.135

実験手法

X-RAY DIFFRACTION (2.006 Å)