298 



2. ANALOGS OF ENZYME REACTION COMPONENTS 



were observed later (Warner, 1951), with K^ 2.5 mM for the potato en- 

 zyme and 0.6 mM for the mushroom enzyme. An excellent investigation 

 by Kuttner and Wagreich (1953) of the inhibition of a catechol oxidase 

 from Psalliota campestris provides data from which some ideas of the me- 

 chanism may be obtained. Some of the inhibition data are presented in 

 Table 2-6, and have been used to calculate the apparent relative binding 

 energies. However, these inhibitors are mostly weak acids and the degree 



Table 2-6 



Inhibition of a Phenol Oxidase from Psalliota campestris with Catechol ( 1 .82 mM) 

 AS Substrate (at pH 5.2 and 25°) 



" The relative energies of binding to the enzyme were calculated assuming competi- 

 tive inhibition and without taking into account the state of ionization. (Data from 

 Kuttner and Wagreich, 1953.) 



