Isatin enzyme interactions. V. Activation of rat liver acid phosphatase

Influence of Isatin on rat tissue acid phosphatase has been studied. It has an organ-specific effect, the liver enzyme is activated, the brain enzyme is inhibited while those of kidney and intestine are not affected. Isatin activation of the liver enzyme is of mixed type and pH dependent. Rat liver enzyme appears to require intact amino and sulfhydryl groups for activity. Isatin seems to combine with the enzyme through the sulfhydryl group of the latter.