Electron transfer in ruthenium-modified proteins

Morten J. Bjerrum; Danilo R. Casimiro; I. Jy Chang; Angel J. Di Bilio; Harry B. Gray; Michael G. Hill; Ralf Langen; Gary A. Mines; Lars K. Skov; Jay R. Winkler; Deborah S. Wuttke

doi:10.1007/BF02110099

Electron transfer in ruthenium-modified proteins

Morten J. Bjerrum, Danilo R. Casimiro, I. Jy Chang, Angel J. Di Bilio, Harry B. Gray^*, Michael G. Hill, Ralf Langen, Gary A. Mines, Lars K. Skov, Jay R. Winkler, Deborah S. Wuttke

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

120 Citations (Scopus)

Abstract

Photochemical techniques have been used to measure the kinetics of intramolecular electron transfer in Ru(bpy)₂(im)(His)²⁺-modified (bpy = 2,2′-bipyridine; im = imidazole) cytochrome c and azurin. A driving-force study with the His33 derivatives of cytochrome c indicates that the reorganization energy (γ) for Fe²⁺→Ru³⁺ ET reactions is 0.8 eV. Reductions of the ferriheme by either an excited complex,^*Ru²⁺, or a reduced complex, Ru⁺, are anomalously fast and may involve formation of an electronically excited ferroheme. The distance dependence of Fe²⁺→Ru³⁺ and Cu⁺→Ru³⁺ electron transfer in 12 different Ru-modified cytochromes and azurins has been analyzed using a tunneling-pathway model. The ET rates in 10 of the 12 systems exhibit an exponential dependence on metal-metal separation (decay constant of 1.06 å^-1) that is consistent with predictions of the pathway model.

Original language	English
Pages (from-to)	295-302
Number of pages	8
Journal	Journal of Bioenergetics and Biomembranes
Volume	27
Issue number	3
DOIs	https://doi.org/10.1007/BF02110099
Publication status	Published - 1995 Jun
Externally published	Yes

Keywords

Electron transfer
azurin
cytochrome c
driving-force dependence
electronic coupling
ruthenium

ASJC Scopus subject areas

Physiology
Cell Biology

Access to Document

10.1007/BF02110099

Cite this

@article{15909341a89e4d4a835e4d04cedd37b4,

title = "Electron transfer in ruthenium-modified proteins",

abstract = "Photochemical techniques have been used to measure the kinetics of intramolecular electron transfer in Ru(bpy)2(im)(His)2+-modified (bpy = 2,2′-bipyridine; im = imidazole) cytochrome c and azurin. A driving-force study with the His33 derivatives of cytochrome c indicates that the reorganization energy (γ) for Fe2+→Ru3+ ET reactions is 0.8 eV. Reductions of the ferriheme by either an excited complex,*Ru2+, or a reduced complex, Ru+, are anomalously fast and may involve formation of an electronically excited ferroheme. The distance dependence of Fe2+→Ru3+ and Cu+→Ru3+ electron transfer in 12 different Ru-modified cytochromes and azurins has been analyzed using a tunneling-pathway model. The ET rates in 10 of the 12 systems exhibit an exponential dependence on metal-metal separation (decay constant of 1.06 {\aa}-1) that is consistent with predictions of the pathway model.",

keywords = "Electron transfer, azurin, cytochrome c, driving-force dependence, electronic coupling, ruthenium",

author = "Bjerrum, {Morten J.} and Casimiro, {Danilo R.} and Chang, {I. Jy} and {Di Bilio}, {Angel J.} and Gray, {Harry B.} and Hill, {Michael G.} and Ralf Langen and Mines, {Gary A.} and Skov, {Lars K.} and Winkler, {Jay R.} and Wuttke, {Deborah S.}",

year = "1995",

month = jun,

doi = "10.1007/BF02110099",

language = "English",

volume = "27",

pages = "295--302",

journal = "Journal of Bioenergetics and Biomembranes",

issn = "0145-479X",

publisher = "Springer New York",

number = "3",

}

TY - JOUR

T1 - Electron transfer in ruthenium-modified proteins

AU - Bjerrum, Morten J.

AU - Casimiro, Danilo R.

AU - Chang, I. Jy

AU - Di Bilio, Angel J.

AU - Gray, Harry B.

AU - Hill, Michael G.

AU - Langen, Ralf

AU - Mines, Gary A.

AU - Skov, Lars K.

AU - Winkler, Jay R.

AU - Wuttke, Deborah S.

PY - 1995/6

Y1 - 1995/6

N2 - Photochemical techniques have been used to measure the kinetics of intramolecular electron transfer in Ru(bpy)2(im)(His)2+-modified (bpy = 2,2′-bipyridine; im = imidazole) cytochrome c and azurin. A driving-force study with the His33 derivatives of cytochrome c indicates that the reorganization energy (γ) for Fe2+→Ru3+ ET reactions is 0.8 eV. Reductions of the ferriheme by either an excited complex,*Ru2+, or a reduced complex, Ru+, are anomalously fast and may involve formation of an electronically excited ferroheme. The distance dependence of Fe2+→Ru3+ and Cu+→Ru3+ electron transfer in 12 different Ru-modified cytochromes and azurins has been analyzed using a tunneling-pathway model. The ET rates in 10 of the 12 systems exhibit an exponential dependence on metal-metal separation (decay constant of 1.06 å-1) that is consistent with predictions of the pathway model.

AB - Photochemical techniques have been used to measure the kinetics of intramolecular electron transfer in Ru(bpy)2(im)(His)2+-modified (bpy = 2,2′-bipyridine; im = imidazole) cytochrome c and azurin. A driving-force study with the His33 derivatives of cytochrome c indicates that the reorganization energy (γ) for Fe2+→Ru3+ ET reactions is 0.8 eV. Reductions of the ferriheme by either an excited complex,*Ru2+, or a reduced complex, Ru+, are anomalously fast and may involve formation of an electronically excited ferroheme. The distance dependence of Fe2+→Ru3+ and Cu+→Ru3+ electron transfer in 12 different Ru-modified cytochromes and azurins has been analyzed using a tunneling-pathway model. The ET rates in 10 of the 12 systems exhibit an exponential dependence on metal-metal separation (decay constant of 1.06 å-1) that is consistent with predictions of the pathway model.

KW - Electron transfer

KW - azurin

KW - cytochrome c

KW - driving-force dependence

KW - electronic coupling

KW - ruthenium

UR - http://www.scopus.com/inward/record.url?scp=0028787957&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028787957&partnerID=8YFLogxK

U2 - 10.1007/BF02110099

DO - 10.1007/BF02110099

M3 - Article

C2 - 8847343

AN - SCOPUS:0028787957

SN - 0145-479X

VL - 27

SP - 295

EP - 302

JO - Journal of Bioenergetics and Biomembranes

JF - Journal of Bioenergetics and Biomembranes

IS - 3

ER -

Electron transfer in ruthenium-modified proteins

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this