Kinetics of conformational changes in the globular head of calf thymus H1 upon tryptic digestion.

The influence of the N- and C-terminal tails on the conformation of the globular domain of histone H1 from calf thymus has been investigated by monitoring the changes in absorption far UV circular dichroism and fluorescence spectra due to the tryptic digestion of the molecule. The values of kinetic constants obtained for the time course of the reaction followed by different above mentioned techniques seem to indicate that whereas the relaxation in the tyrosine environment occurs due to the digestion of the polar tails, the alpha-helix content increases in the earlier phase of the digestion.