Dioxygen activation at non-heme diiron centers:: Characterization of intermediates in a mutant form of toluene/o-xylene monooxygenase hydroxylase

被引：44

作者：

Murray, Leslie J. ^{[1
]}

Garcia-Serres, Ricardo

Naik, Sunil

Huynh, Boi Hanh

Lippard, Stephen J.

机构：

[1] Emory Univ, Dept Phys, Atlanta, GA 30322 USA

[2] MIT, Dept Chem, Cambridge, MA 02139 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2006年 / 128卷 / 23期

关键词：

D O I：

10.1021/ja062762l

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

We report the generation and characterization of an intermediate in a mutant form of the toluene/o-xylene monooxygenase hydroxylase component from Pseudomonas stutzeri OX1. The reaction of chemically reduced I100W variant in the presence of the coupling protein, ToMOD, with dioxygen was monitored by stopped-flow UV/visible spectroscopy. Rapid-freeze quench (RFQ) samples were also generated for EPR and Mössbauer spectroscopy. A transient species is observed in the UV/visible spectrum with an absorption maximum at 500 nm. EPR and Mössbauer spectra of RFQ samples identified this species as a diiron(III,IV) cluster spin-coupled to a neutral W radical. A diamagnetic precursor to the mixed-valent diiron(III,IV) was also observed at an earlier time point, with Mössbauer parameters typical of high-spin FeIII. We have tentatively assigned this antiferromagnetically coupled diiron(III) intermediate as a peroxo-bridged cluster, and this complex has also been observed in preliminary studies of the wild-type hydroxylase. Copyright © 2006 American Chemical Society.

引用

页码：7458 / 7459

页数：2

共 37 条

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ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 2004, 43 (07) : 834 - 838
[32] X-ray crystal structures of manganese(II)-reconstituted and native toluene/o-xylene monooxygenase hydroxylase reveal rotamer shifts in conserved residues and an enhanced view of the protein interior
McCormick, Michael S.
Sazinsky, Matthew H.
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Lippard, Stephen J.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2006, 128 (47) : 15108 - 15110
[33] Crystal structure of the toluene/o-xylene monooxygenase hydroxylase from Pseudomonas stutzeri OX1 -: Insight into the substrate specificity, substrate channeling, and active site tuning of multicomponent monooxygenases
Sazinsky, MH
Bard, J
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Lippard, SJ
JOURNAL OF BIOLOGICAL CHEMISTRY, 2004, 279 (29) : 30600 - 30610
[34] X-ray crystal structures of manganese(II)-reconstituted and native toluene/o-xylene monooxygenase hydroxylase reveal rotamer shifts in conserved residues and an enhanced view of the protein interior
McCormick, Michael S.
Sazinsky, Matthew H.
Condon, Karen L.
Lippard, Stephen J.
Journal of the American Chemical Society, 2006, 128 (47): : 15108 - 15110
[35] Modeling features of the non-heme diiron cores in O2-activating enzymes through the synthesis, characterization, and oxidation of 1,8-naphthyridine-based complexes
Kuzelka, J
Mukhopadhyay, S
Spingler, B
Lippard, SJ
INORGANIC CHEMISTRY, 2003, 42 (20) : 6447 - 6457
[36] Synthesis and characterization of {Fe2(Yi-OH)2(Yi-O2Cr)}3+ and {Fe2(Yi-O)(Yi-O2Cr)}3+ complexes with a carboxylate-rich metal coordination environment as models for diiron centers in dioxygen-dependent non-heme enzymes.
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Lippard, S
ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 2004, 227 : U1544 - U1544
[37] A density functional study of possible intermediates of the reaction of dioxygen molecule with non-heme iron complexes. 1. N-side versus O-side mechanism with water-free model
Torrent, M
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JOURNAL OF PHYSICAL CHEMISTRY B, 2001, 105 (36): : 8616 - 8628

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