Abstract
We have observed the rate of oxymyoglobin (MbO2) photodissociation at room temperature and carboxymyoglobin (MbCO) photodissociation as a function of temperature (260-10 K) by means of picosecond spectroscopy. The Mb + O2 and Mb + CO photodissociated states have also been characterized. Based on the picosecond experimental data, we postulate that the photodissociation of ligated myoglobin is a nonactivitated process, and the mechanism involves either a small enthalpy barrier or none at all.
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Selected References
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