4E4Z

Oxidized (Cu2+) peptidylglycine alpha-hydroxylating monooxygenase (PHM) in complex with hydrogen peroxide (1.98 A)

4E4Z の概要

• エントリーDOI: 10.2210/pdb4e4z/pdb
• 関連するPDBエントリー: 1OPM 1PHM 1SDW 3MIB 3MIK 3MLK
• 分子名称: Peptidyl-glycine alpha-amidating monooxygenase, COPPER (II) ION, NICKEL (II) ION, ... (6 entities in total)
• 機能のキーワード: catalysis, mixed function oxygenases, multienzyme complexes, stereoisomerism, oxidoreductase
• 由来する生物種: Rattus norvegicus (brown rat,rat,rats)
• 細胞内の位置: Cytoplasmic vesicle, secretory vesicle membrane; Single-pass membrane protein: P14925
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 35362.06

構造登録者

Rudzka, K.,Amzel, L.M. (登録日: 2012-03-13, 公開日: 2013-01-23, 最終更新日: 2024-10-30)

主引用文献

Rudzka, K.,Moreno, D.M.,Eipper, B.,Mains, R.,Estrin, D.A.,Amzel, L.M.
Coordination of peroxide to the Cu(M) center of peptidylglycine alpha-hydroxylating monooxygenase (PHM): structural and computational study.
J.Biol.Inorg.Chem., 18:223-232, 2013

PubMed Abstract: Many bioactive peptides, such as hormones and neuropeptides, require amidation at the C terminus for their full biological activity. Peptidylglycine α-hydroxylating monooxygenase (PHM) performs the first step of the amidation reaction-the hydroxylation of peptidylglycine substrates at the Cα position of the terminal glycine. The hydroxylation reaction is copper- and O(2)-dependent and requires 2 equiv of exogenous reductant. The proposed mechanism suggests that O(2) is reduced by two electrons, each provided by one of two nonequivalent copper sites in PHM (Cu(H) and Cu(M)). The characteristics of the reduced oxygen species in the PHM reaction and the identity of the reactive intermediate remain uncertain. To further investigate the nature of the key intermediates in the PHM cycle, we determined the structure of the oxidized form of PHM complexed with hydrogen peroxide. In this 1.98-Å-resolution structure (hydro)peroxide binds solely to Cu(M) in a slightly asymmetric side-on mode. The O-O interatomic distance of the copper-bound ligand is 1.5 Å, characteristic of peroxide/hydroperoxide species, and the Cu-O distances are 2.0 and 2.1 Å. Density functional theory calculations using the first coordination sphere of the Cu(M) active site as a model system show that the computed energies of the side-on L(3)Cu(M)(II)-O(2) (2-) species and its isomeric, end-on structure L(3)Cu(M)(I)-O(2) (·-) are similar, suggesting that both these intermediates are significantly populated within the protein environment. This observation has important mechanistic implications. The geometry of the observed side-on coordinated peroxide ligand in L(3)Cu(M)(II)O(2) (2-) is in good agreement with the results of a hybrid quantum mechanical-molecular mechanical optimization of this species.

PubMed: 23247335
DOI: 10.1007/s00775-012-0967-z

実験手法

X-RAY DIFFRACTION (1.98 Å)