The kinetics of carbon monoxide binding to partially reduced methemoglobin

Abstract

The pulse radiolysis technique has been used to study the kinetics of the CO binding to partially reduced methemoglobin. Experiments with horse heart metmyoglobin show that this technique gives results which are in good agreement with those obtained by other methods. The kinetics of the CO binding to partially reduced methemoglobin show two phases, whose amplitudes appear to depend on the degree of reduction in such a way that they can be attributed to methemoglobin molecules with one or two reduced heme groups. In the presence of inositol hexaphosphate the rate of CO binding to partially reduced methemoglobin decreases strongly. With inositol hexaphosphate a slight biphasic behavior is observed independent of the degree of reduction.