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


  • 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


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


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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