Microsecond Laser Flash Photolysis of the CO-Complex of Bovine Heart Cytochrome c Oxidase

Authors

  • Abubakar M.K. Department of Biochemistry, Usmanu Danfodiyo University, Sokoto, Nigeria Author
  • Bilbis L.S. Department of Biochemistry, Usmanu Danfodiyo University, Sokoto, Nigeria Author
  • Shehu R.A. Department of Biochemistry, Usmanu Danfodiyo University, Sokoto, Nigeria. Author

Abstract

Bovine heart cytochrome c oxidase was prepared accordinq to the method of Yonetani (1961), the COcomplex
of the fully reduced and mixed valence enzyme was prepared as described by Bicker et al. (1984). Kinetics of
CO rebinding subsequent to Laser photolysis was studied at 430nm by using a 20ns pulsed at 532nm vertically polarized
Laser beam of 2mJ energy. The results suggest differences in photodynamic behaviour of the fully reduced and mixed
valence forms of the enzyme. The most important implication of this, is at the conformational changes associated with
the reduction of the low spin cytochrome a affects the ligation dynamic of the oxygen reduction site via heterotropic
interaction.

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References

Abubakar,M.K. (1994) Studies of the structural and functional dynamics of cytochrome c oxidase. Ph.D.Thesis,Universityof Essex.

Bickar, D.; Bonavenlure, C. and Bonaventure, J. (1984). Carbon rnonoxide-drlvenreduction of ferric heme and heme proteins. J. BioI. Chem. 259(17), 10777-83.

Brunorl, M.; Colosimo, A.; Wilson, M.T.; Sarti, P. and Antonini, E. (1983). Interconversion between states In cytochrome oxidase: Interpretation of kinetic data on mixed-valence oxidase. FEBS lells. 152(1),75 - 78.

Brunori, M.; Antonini, G.; Guiffre, A.; Malatesta, F.; Nicholelle, F.; Sarti, P. and Wilson, M.T. (1994).

Electron transfer and ligand binding In terminal oxidase: Impact of recent structural information. FEBS Lells. 350, 164 - 168.

Greenwood, C.; Wilson, M.T. and Brunori, M. (1974). Studies on partially reduced mammalian cytochrome oxidase: Reaction with carbon monoxide and oxygen. Biochem. J. 137, 205-215.

Hosler, J.P.; Ferguson-Miller,S.; Calhoun, M.W.; Thomas, J.W.; Hill, J.; Lemieux, l.; Ma, J.; Georgiou, G.; Fetter, J.; Shapleigh, J.;

Teclenburq, M.M.J.; Babcock, G.T. and Gennis, R.B. (1993). Insight into the active site structure and function of cytochrome oxidase by analysis of site-directed mutants of bacterial cytochrome aa3 and cytochrome boo J. Bioenerg. Bicmember. 25, 121 - 135.

Lou, B.S.; Larsen, RW.; Chan, 5.1. and Ondrias, RM. (1993). Conformational dependence of carbon monoxide ligallon dynamics In cytochrome coxidase. J. Amer. Chem. Soc. 115, 403 -.407.

Rich, P.R (1995). Towards an understanding of the chemistry of oxygen reduction and proton translocation In the iron-copper respiratory oxidases. Austr. J. Plant Physlol. 22, 479-486.

Wikstrom, M. (1977). Proton pump coupled to cytochrome c oxidase In mitochondria. Nature 266, 271 - 273.

Wilson, M.T.; Antonini, G.; Malatesta, F.; Sarti, P. and Brunori, M. (1994). Probing the oxygen binding site of cytochrome c oxidase by cyanide. J. BioI. Chem. 269(39),24114 - 9.

Woodruff, W.H. (1993). Coordination dynamics of heme-copper oxidases. The ligand shutlle and the control and coupling of electron transfer and proton translocation. J. Bioenerg. Biomembr. 23(5), 177 - 185.

Yonetanf, T. (1960). Studies on cytochrome oxidase. I. Absolute. and difference absorpllon spectra. J. BioI. Chem. 235(3), 845 - 852.

Yonetani, T. (1961). Studies on cytochrome c oxidase III. Improved preparation and properties. J. BioI. Chem. 236, 1680 - 1688.

Published

1999-06-30

How to Cite

Microsecond Laser Flash Photolysis of the CO-Complex of Bovine Heart Cytochrome c Oxidase. (1999). Nigerian Journal of Biochemistry and Molecular Biology, 14, 49-54. https://www.nsbmb.org.ng/journals/index.php/njbmb/article/view/340