Transient kinetic studies of Neurospora crassa cytochrome c oxidase.
The reaction of Neurospora crassa cytochrome c oxidase with CO was studied by flash-photolysis and rapid-mixing experiments, leading to the determination of the association and dissociation rate constants (7 X 10(4) M-1 X s-1 and 0.02s-1 respectively). Pre-steady-state kinetic investigations of the catalytic properties of the enzyme showed that under proper conditions Neurospora cytochrome c oxidase can be 'pulsed', i.e. activated, like the mammalian enzyme. The 'pulsed' species is spectroscopically different from the 'resting' one, and the decay into the 'resting' state is fast (t1/2 approx. 3 min).
D002248:Carbon Monoxide / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism*; D007700:Kinetics; D009491:Neurospora / Q000201:enzymology*; D009492:Neurospora crassa / Q000201:enzymology*; D010084:Oxidation-Reduction; D013053:Spectrophotometry
D002248:Carbon Monoxide; D003576:Electron Transport Complex IV