Enzymes 



189 



pier phosphodiesters (p. 177), the distribution of activity is 

 identical with that of alkaline phosphatase. It appears very 

 likely that the nonspecific enzyme is responsible for the histo- 

 chemical reactions obtained with the use of phosphodiester 

 substrates. 



Acid Phosphatase 



Phosphatases with very low pH optima have been de- 

 scribed in fungi and in higher plants. A phosphatase with a 

 pH optimum of ±: 5 was found in the spleen and liver by 

 Davies^^ and later in the prostate by Kutscher.^^ Acid phos- 

 phatases, as a rule, are not activated by Mg and almost in- 

 variably are greatly inhibited by fluoride. Enzymes of animal 

 origin may show considerable differences in respect to their 

 behavior toward inhibitors, as shown in Table 4. 



TABLE 4 



The Inhibition of Acid Phosphatases by Various Substances* 



*0 indicates no inhibition; 4, maximum inhibition; 1-3, intermediate degrees; — indicates no 

 data available. 



a Gutman, E. B., and Gutman, A. B.: J. Clin. Investigation, 17:473, 1938. 



b Abul-Fadl, M. A. M., and King, E. J.: J. Clin. Path., 1:80, 1948. 



Herbert, F. K.: Biochem. J., 38:23, 1944. 



d Abul-Fadl, M. A. M., and King, E. J.: Biochem. J., 42:28, 1948. 



e Abul-Fadl, M. A. M., and King, E. J.: Biochem. J., 45:51, 1949. 



f Gutman, E. B., and Gutman, A. B.: Proc. Soc. Exper. Biol. & Med., 47:513, 1941. 



8 Behrendt, H.: Proc. Soc. Exper. Biol. & Med., 54:268, 1943. 



h King, E. J., Wood, E. J., and Delory, G. E.: Biochem. J., 39:24, 1945. 



> Abul-Fadl, M. A. M., and King, E. J.: J. Path. & Bact., 60: 149, 1948. 



i Seligman, A. M., and Manheimer, L. H.: J. Nat. Cancer Inst., 9:427, 1949; Seligman, A. M., 

 Nachlas, M. M., Manheimer, L. H., Friedman, O. M., and Wolf, G.: Ann. Surg., 130:333, 1949. 



62. Davies, D. R.: Biochem. J., 28:529, 1934. 



63. Kutscher, W., and Wolbergs, H.: Ztschr. f. physiol. Chem., 236:237, 

 1935. 



