Dynamics of Carbon Monoxide Binding by Heme Proteins

Science  10 Aug 1973:
Vol. 181, Issue 4099, pp. 541-543
DOI: 10.1126/science.181.4099.541


Rebinding of carbon monoxide to myoglobin and to cytochrome P-450 after removal by a light flash occurs down to 50°K for myoglobin and 25°K for cytochrome P-450 in glycerol-water solution. Above 240°K the reaction is second order; between 240° and 200°K the rebinding becomes exponential and independent of the carbon monoxide concentration. Below 150°K the reaction follows a power law and is approximately 103 times faster for cytochrome P-450 than for myoglobin.