Incoherent control of protein conformational state

The peaks in the temperature-derivative spectra of horse myoglobin-CO are simulated for two cooling protocols: in the dark and under illumination. The appropriate Smoluchowski equations for both cooling/preparation and heating/monitoring steps are solved for parameters previously obtained by fitting the transient isothermal binding kinetics. The qualitative agreement with experiment suggests that the new peak observed after slow cooling under illumination arises from population which relaxes in the deoxy state during both cooling and heating steps. The analysis shows how temperature and light allow one to control the inhomogeneous conformational distribution in myoglobin.