Spectroscopic evidence for a heme-superoxide/Cu(I) intermediate in a functional model of cytochrome C oxidase

被引：53

作者：

Collman, JP ^{[1
]}

Sunderland, CJ ^{[1
]}

Berg, KE ^{[1
]}

Vance, MA ^{[1
]}

Solomon, EI ^{[1
]}

机构：

[1] Stanford Univ, Dept Chem, Stanford, CA 94305 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2003年 / 125卷 / 22期

关键词：

D O I：

10.1021/ja034382v

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A superstructured tetraphenylporphyrin with a covalently attached proximal imidazole axial base and three distal imidazole pickets has been developed as a model for the active site of terminal oxidases such as cytochrome c oxidase. The oxygen adduct of the Fe-only heme (at low temperature) has a diamagnetic NMR and is EPR silent, which taken together with a resonance Raman oxygen isotope sensitive band (νFe-O) at 575/554 cm-1 (16O2/18O2) indicates formation of a six-coordinate heme-superoxide complex. Unexpectedly, the Fe/Cu complex, where the copper is in a trisimidazole environment ∼5 Å above the heme plane, displays similar characteristics: a diamagnetic NMR, EPR silence, and νFe-O at 570/544 cm-1. This indicates the dioxygen adduct of this Fe/Cu system is also a superoxide. This contrasts with previously characterized partially reduced dioxygen intermediates of binuclear heme/copper complexes that form Fe/Cu μ-peroxo complexes. Copyright © 2003 American Chemical Society.

引用

页码：6648 / 6649

页数：2

共 18 条

[1] Functional analogues of the dioxygen reduction site in cytochrome oxidase:: Mechanistic aspects and possible effects of CuB
Boulatov, R
Collman, JP
Shiryaeva, IM
Sunderland, CJ
[J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2002, 124 (40) : 11923 - 11935
[2] STRUCTURE-SENSITIVE RESONANCE RAMAN BANDS OF TETRAPHENYL AND PICKET FENCE PORPHYRIN-IRON COMPLEXES, INCLUDING AN OXYHEMOGLOBIN ANALOG
BURKE, JM
KINCAID, JR
PETERS, S
GAGNE, RR
COLLMAN, JP
SPIRO, TG
[J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1978, 100 (19) : 6083 - 6088
[3] Distal metal effects in cobalt porphyrins related to CcO
Collman, JP
Berg, KE
Sunderland, CJ
Aukauloo, A
Vance, MA
Solomon, EI
[J]. INORGANIC CHEMISTRY, 2002, 41 (25) : 6583 - 6596
[4] Biomimetic studies of terminal oxidases: Trisimidazole picket metalloporphyrins
Collman, JP
Sunderland, CJ
Boulatov, R
[J]. INORGANIC CHEMISTRY, 2002, 41 (08) : 2282 - 2291
[5] A functional model related to cytochrome c oxidase and its electrocatalytic four-electron reduction of O-2
Collman, JP
Fu, L
Herrmann, PC
Zhang, XM
[J]. SCIENCE, 1997, 275 (5302) : 949 - 951
[6] A SYNTHETIC ANALOG FOR THE OXYGEN-BINDING SITE IN CYTOCHROME-C-OXIDASE
COLLMAN, JP
HERRMANN, PC
BOITREL, B
ZHANG, XM
EBERSPACHER, TA
FU, L
WANG, JL
ROUSSEAU, DL
WILLIAMS, ER
[J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1994, 116 (21) : 9783 - 9784
[7] Collman JP, 1998, ANGEW CHEM INT EDIT, V37, P3397, DOI 10.1002/(SICI)1521-3773(19981231)37:24<3397::AID-ANIE3397>3.0.CO
[8] 2-N
[9] COLLMAN JP, 2003, PORPHYRIN HDB, V11
[10] Mass spectrometric determination of dioxygen bond splitting in the "peroxy" intermediate of cytochrome c oxidase
Fabian, M
Wong, WW
Gennis, RB
Palmer, G
[J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1999, 96 (23) : 13114 - 13117

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