Spectrophotometric characterization of intermediate redox states of cytochrome oxidase.
The spectrophotometric characteristics of hemes a and a3 in cytochrome oxidase have been examined over the range 380 nm to 900 nm. Difference spectra (relative to the oxidized form) are presented for ferrous, high-spin oxidized, low-spin oxidized, early "pulsed," late "pulsed," and two-peroxide-treated states of the enzyme. Comparisons indicate that the decay product of the initial peroxide complex of the enzyme is identical to a low-spin pulsed form of the enzyme. A high-spin pulsed form of the enzyme persists for several hours to days after preparation.
Wrigglesworth
J M
JM
Department of Biochemistry, Kings College, London University, England.
Ioannidis
N
N
Nicholls
P
P
D003486:Cyanides / Q000494:pharmacology; D004227:Dithionite / Q000494:pharmacology; D003576:Electron Transport Complex IV / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007700:Kinetics; D010084:Oxidation-Reduction; D010545:Peroxides / Q000378:metabolism; D013053:Spectrophotometry / Q000379:methods
D003486:Cyanides; D010545:Peroxides; D004227:Dithionite; D006861:Hydrogen Peroxide; D003576:Electron Transport Complex IV