Spin label detection of intermolecular interactions in carbonmonoxy sickle hemoglobin

With recently developed spin label techniques for monitoring macromolecular rotational motion, heme-liganded sickle cell hemoglobin in the presence of inositol hexaphosphate is shown to exhibit restricted motional freedom as compared to liganded normal adult human hemoglobin. This motional restriction is dependent on both hemoglobin concentration and temperature.