[Determination of the correlation time of the lysozyme molecule and lysozyme-inhibitor complex using a spin-label...

Temperature relationships of rotational correlation times (tau M) of lysozyme molecules were studied using viscosity method based on the model of slow feebly anisotropic rotation of label N-O-group. Protein is mainly associated in 0.01 phosphate buffer (pH 7.3) at 5-30 degrees C. Formation of the complex of lysozyme with competitive inhibitor (3-N-AGA) leads to changes of tau M. It may be due to a decrease of polymerization degree and increase of the protein packing. It is suggested that two-component form of ESR spectra of different spin labeled proteins reflects their common ability for pulsations between more and less compact conformers due to the thermal relative movements of domains and subunits.