The influence of urea and guanidine chloride on the binding of the binding of the bacterial substrate and inhibitors to hen lysozyme at physiological temperature (40 degrees) (*).

The influence of urea and of guanidine chloride on the binding of the bacterial substrate and of inhibitors such as N-acetylglucosamine or chitotetraose to hen lysozyme were studied at 20 degrees and at 40 degrees C (physiological temperature). The action of urea did not prevent a certain degree of organization of the enzyme compatible with its usual behaviour in the presence of some inhibitors and with its crystallization ; guanidine chloride, already at low concentrations, seemed to have a more severe effect on lysozyme.