Myoglobin recombination at low temperature: Exponential and non exponential phases revealed by FTIR spectroscopy.
01 January 1987
The low temperature recombination of CO with myoglobin was studied using Fourier transform infrared spectroscopy. The bound state of MbCO has two distinct conformers observed at 1926 and 1945cm sup(-1) with an intensity ratio of 1 to 8. The recombination of these bands after complete photolysis at 10K followed by a temperature jump shows distinct kinetics for the two bands. The 1945cm sup (-1) band apparently follows the non-exponential kinetics originally described by Frauenfelder et. al. (Austin et. al., Biochemistry, 1975, v.14, p.5355- 5373.) But, the 1926cm sup (-1) band does not appear appreciably below 70K and appears with simple exponential kinetics at 80K and above.