328 H. B. TAYLOR. 
values of A;, the rate of inactivation of the enzyme, can be 
calculated from the initial velocity A. This formula is as 
follows :— 
Kab 
a—2x 
] 
K Ks 
3 et teres (IR ESE 
ots Te. | 5 ) 
where a and a — x have the usual meanings, and E is the 
initial concentration of the enzyme. 
If in this formula, t is put equal to 2, a—x becomes 
equal to the concentration of hydrogen peroxide at the end 
of the reaction, and the equation then takes the form, 
ao K 
log - = 1 = || 
The values of A used for the calculation of A; according 
to Tammann’s formula must be those which are obtained by 
taking into consideration the end point of the reaction. 
The values for A are shown under 4A, in Tables [IX and X. 
(1) Effect of hydrogen peroarde on value of Kg. 
Since the rate of decomposition of hydrogen peroxide 
decreases with increase of hydrogen peroxide concentration 
as Shown under A in Table VI, it would be expected that 
the rate of destruction of the enzyme A, would increase as 
the values of A decrease. That this is the case is seen 
from Table IX. 
Table IX, 
Temperature 25° C. 
Concentration | Concentration KX104 | K.X104 Ke X104 
of enzyme. of hyd. peroxide. 5 ; 
1 |  ™M/500 53 122 446 
M/160 42 216 1893 
M/120 36 227 2465 
M/80 a 257 3609 
(2) Effect of Temperature. 
The rate of destruction of the enzyme, as will be seen 
from the following figures, is very greatly increased by the 
rise of temperature. 
