The asymmetric distribution of charges on the surface of horse cytochrome c. Functional implications.

Koppenol, Willem H.; Margoliash, E.

doi:10.1016/s0021-9258(18)34740-9

Cited by 372 publications

(163 citation statements)

References 63 publications

Supporting

Mentioning

159

Contrasting

Order By: Relevance

“…cytochrome c1, cytochrome oxidase and cytochrome peroxidase), as well as with low molecular weight metal complexes. For the binding of the latter in the precursor complex, NMR and kinetic measurements, as a function of ionic strength and chemical modifications of the surface residues of the protein, have allowed researchers to determine three generally reactive areas (Brautigan et al 1978;König et al 1980;Webb et al 1980;Ahmed & Millett 1981;Butler et al 1981Butler et al , 1983Boswell et al 1982;Eley et al 1982;Koppenol & Margoliash 1982;Williams et al 1982;Moore et al 1984;Armstrong et al 1986;Drake et al 1989). These areas, located on both sides of the haem, are found to react preferentially either with anionic or cationic species.…”

Section: Discussionmentioning

confidence: 99%

Electron-transfer‐mediated binding of optically active cobalt(III) complexes to horse heart cytochromec

Scholten

Merchán

Bernauer

2005

J. R. Soc. Interface.

View full text Add to dashboard Cite

Optically active cobalt(II) complexes are used as reducing agents in the electron-transfer reaction involving horse heart cytochrome c. Analysis of the circular dichroism (CD) spectra of reaction products indicates that the corresponding cobalt(III) species of both enantiomers of [Co) are partly attached to the protein during electron transfer by coordination to an imidazole unit of one of the histidine residues. His-26 and His-33 are both solvent exposed, and the results suggest that one of these histidine residues acts as a bridge in the electron transfer to and from the haem iron of cytochrome c. The reaction is enantioselective: the ratio of the relative reactivity at 15 8C is 2.9 in favour of the R,R-enantiomer. A small induced CD activity in the haem chromophore reveals that some structural changes in the protein occur consecutively with the binding of the cobalt(III) complex.

show abstract

Section: Discussionmentioning

confidence: 99%

Electron-transfer‐mediated binding of optically active cobalt(III) complexes to horse heart cytochromec

Scholten

Merchán

Bernauer

2005

J. R. Soc. Interface.

View full text Add to dashboard Cite

show abstract

“…In another approach to ionic strength effects [172][173][174][175], it is assumed that the transition state of the reaction (denoted by AB*) can be regarded as a single body rather than a pair of reactants. The rate constant can then be written as in Eqn.…”

Section: Ivd Work Terms For Bimolecular Reactions Involving Metalloproteinsmentioning

confidence: 99%

Electron transfers in chemistry and biology

Marcus

Sutin

1985

Biochimica et Biophysica Acta (BBA) - Reviews on Bioenergetics

8,233

230

7,865

View full text Add to dashboard Cite

show abstract

“…•and N 3 • , we propose that CO 3 •reacts with iron(II) cytochrome c at the solvent-accessible haem edge. This area occupies approximately 1% of the surface of cytochrome c, is more easily oxidized than an amino acid, and negatively charged reactants are guided towards it by the electric potential field generated by the asymmetric charge distribution of the protein [46,47].…”

Section: Comentioning

confidence: 99%

Oxidation-state-dependent reactions of cytochrome c with the trioxidocarbonate(•1−) radical: a pulse radiolysis study

Domazou

Koppenol

2006

J Biol Inorg Chem

View full text Add to dashboard Cite

The reaction of the trioxidocarbonate(*1-) radical (CO (3) (*-) , "carbonate radical anion") with cytochrome c was studied by pulse radiolysis at alkaline pH and room temperature. With iron(III) cytochrome c, CO (3) (*-) reacts with the protein moiety with rate constants of (5.1 +/- 0.6) x 10(7) M(-1) s(-1) (pH 8.4, I approximately 0.27 M) and (1.0 +/- 0.2) x 10(8) M(-1) s(-1) (pH 10, I = 0.5 M). The absorption spectrum of the haem moiety was not changed, thus, amino acid radicals produced on the protein do not reduce the haem. The pH-dependent difference in rate constants may be attributed to differences in ionization states of amino acids and to the change in the conformation of the protein. With iron(II) cytochrome c, CO (3) (*-) oxidizes the haem quantitatively, presumably via electrostatic guidance of the radical to the solvent-accessible haem edge, with a different pH dependence: at pH 8.4, the rate constant is (1.1 +/- 0.1) x 10(9) M(-1) s(-1) and, at pH 10, (7.6 +/- 0.6) x 10(8) M(-1) s(-1). We propose that CO (3) (*-) oxidizes the iron center directly, and that the lower rate observed at pH 10 is due to the different charge distribution of iron(II) cytochrome c.

show abstract

The asymmetric distribution of charges on the surface of horse cytochrome c. Functional implications.

Cited by 372 publications

References 63 publications

Electron-transfer‐mediated binding of optically active cobalt(III) complexes to horse heart cytochromec

Electron-transfer‐mediated binding of optically active cobalt(III) complexes to horse heart cytochromec

Electron transfers in chemistry and biology

Oxidation-state-dependent reactions of cytochrome c with the trioxidocarbonate(•1−) radical: a pulse radiolysis study

Contact Info

Product

Resources

About