ENERGY SUPPLY OF THE CELL 127 



when ko is the reaction constant at the standard temperature To, 

 recorded as absolute temperature. T is the experimental tempera- 

 ture, ^ is a constant characterizing the process involved. 

 Thus, the equation: 



— -Tj- = k^e E{a — x) 



expresses the rate of enzyme action at any temperature. 

 For simpler calculation, we substitute 



A{T-To) 

 T'To 



q = e 

 k = koq 



—^ = koqE{a - x) 



This would be a simple formula if the amount of enzyme remained 

 constant during the experiment. But this is not the case. Enzymes 

 are unstable compounds, readily decomposed in watery solution, and, 

 therefore, decrease during the experiment. In most cases, their 

 deterioration follows the monomolecular reaction 



-I = /..(.-,) 



where b is the original enzyme concentration, y the amount of 

 enzyme decomposed. Here again, K is a function of the tempera- 

 ture, following the same law, but with a different constant. 



K=Koe ^^° 

 For easier calculation, we introduce again the temperature coefficient. 



Q = e^ 

 K = K,Q 



-^ = KoQib - y) 



