480 



EFFECT OF ENZYME ON DIGESTION OF PROTEINS 



value of X therefore in the first 10 per cent of the reaction will 

 increase from to 1 .0. The percentage decrease in Q (the concen- 

 tration of active pepsin) will depend to some extent on the concentra- 

 tion of peptone {d) present at the beginning of the reaction. That 

 this is actually so is shown by the fact that the relative rates of diges- 

 tion of two solutions containing the same amount of pepsin but very 



TABLE III. 

 Enzyme Concentration and Rate of Digestion. 

 Pepsin solution. 1 per cent active pepsin + 10 per cent egg albumin, pH 2.0. 

 Digested 24 hrs. at 37°C. Diluted as below + HCl, pH 2.0. 



19.2 

 K = 8.5 d =^^^ 



different amounts of peptone vary, depending on what stage of the 

 reaction is compared. This is due to the fact that the rate of digestion 

 of the solution containing the peptone decreases more slowly than 

 that of the solution containing no peptone. This is in agreement 

 with the formula. The differences in the percentage decrease in the 

 rates of digestion of two solutions during the first 10 per cent hy- 

 drolysis, due to variations in the relative values of E and d, were found 

 to be too small to effect the results within the range of values of E 

 and d used in these experiments. The relative mean rate for the 

 first 10 per cent hydrolysis may therefore be considered proportional 



