Studies on sulphatases. 5. The determination of inorganic sulphate in the study of sulphatases

Abstract

An adaptation of the benzidine method for determining small amts. of enzymically liberated sulfuric acid in the presence of acetate-buffered biological material is descr. Using this method K sulfate can be recovered quantitatively from tissue suspensions of different organisms under varying conditions of pH and buffer molarity and after incubation for 1 hr. at 37.5[degree]. With the exception of Ba, recoveries of sulfate are unaffected by presence of small amts. of certain inorganic ions. Within certain limits K p-acetylphenylsulfate, K glucose 6-sulfate, K myronate and chondroitinsulfuric acid are without effect on the method. The method was checked under conditions of enzyme expt. by measuring the sulfate liberated from K p-acetylphenylsulfate by rat arylsulfatase. Values obtained were in good agreement with those obtained by calculation after spectrophotometric measurement of the liberated p-hydroxyacetophenone.