Enzymes 199 



indoxyl,^- phenols,^^ estrogens,^^ sugars,^^ and thiogluco- 

 sides.^^ There seem to be four different enzymes involved, 

 v^ith rather sharp substrate specificities. For further details 

 the reader is referred to Fromageot's excellent review ar- 

 ticle.^^ 



Sulfatases hydolyzing sulfates of phenols^^ and of thioglu- 

 cosides^^ have been demonstrated in the tissues of higher 

 animal species. The enzymes are quite resistant to dehydra- 

 tion by acetone.^^ The concentration of enzyme is very low 

 (maximum, 50-60 ^M of substrate hydrolyzed per gram of 

 tissue and per hour;^^ in most cases activity is very much 



lower, usually around 1 per cent of the phosphatase activ- 

 ity) loo 



Theoretically, either the sulfate or the phenolic component 

 could be demonstrated by histochemical methods. The sul- 

 fate method was tried with nitrophenyl sulfate as a sub- 

 strate,^^^ without any success, although this compound is 

 hydrolyzed at a much higher rate than other esters. Ohara 

 and Kurata^^^ have reported positive results by the lead sul- 

 fate technique, using phenyl sulfate or 8-hydroxyquinoline 

 sulfate as substrates. Another method by the same authors 

 demonstrates the sulfate ion by precipitating it with benzi- 

 dine; the latter is then demonstrated with y8-naphthoquinone 

 sulfonate. These methods seem to work with acetone-fixed, 



92. Derrien, M.: Bull. Soc. chim. France, ser. IV, 9:110, 1911. 



93. Neuberg, C, and Kurono, K.: Biochem. Ztschr., 140:295, 1923. 



94. Cohen, H., and Bates, R. W.: Endocrinology, 44:317, 1949. 



95. Soda, T., and Hattori, C: Proc. Imp. Acad. Tokyo, 7:269, 1931. 



96. Neuberg, C, and Wagner, J.: Ztschr. f. d. ges. exper. Med., 56:334, 

 1927. 



97. Fromageot, C: Ergebn. d. Enzymforsch., 7:50, 1938. 



98. Neuberg, C, and Simon, E.: Biochem. Ztschr., 156:365, 1925. 



99. Huggins, C, and Smith, D. R.: J. Biol. Chem., 170:391, 1947. 



100. Rosenfeld, L.: Biochem. Ztschr., 157:434, 1925; Hommerberg, C: 

 Ztschr. f. biol. Chem., 200:69, 1931. 



101. Gomori, G.: Unpublished. 



102. Ohara, M., and Kurata, Y.: Igaku to Seibutsugaku, 16:213, 1950. 



