Veränderungen derp-Nitrophenylphosphataseaktivität aus Lymphozyten durch Concanavalin A

Abstract

The effect of K+, Na+, Mg2+ and ATP on p-nitrophenylphosphatase activity was investigated. As an enzyme preparation, a microsomal fraction of sheep lymphocytes was used. Low concentrations of Mg2+, K+ and Na+ increased, but high concentrations decreased the enzyme activity. There was an inhibition of activity by ATP without Na+ in the incubation medium and an increase of enzyme activity at low K:Na-ratio. Concanavalin A in a concentration of 15 .mu.g/ml caused increased p-nitrophenylphosphatase activity in intact cells and the microsomal fraction for 30-40%. The activation was not Na+, K+, Mg2+, p-nitrophenylphosphate or ATP dependent.