THE KINETICS OF TRYPSIN DIGESTION : V. SCHUTZ'S RULE.

The rate of digestion of concentrated casein solutions by low concentrations of trypsin at 0° has been followed. Under these conditions the enzyme is inhibited by the product of the reaction and under certain conditions this effect should lead to Schütz's rule, i.e. the amount of hydrolysis should be proportional to the square root of the product of the time into the enzyme concentration. This is the result obtained. Both Schütz's rule and Arrhenius' equation fail to hold accurately owing to the incorrect relation assumed to hold between the rate of hydrolysis and the substrate concentration.