[Properties and isoenzymes of acid phosphatase in erythrocytes and various tissues (kidney, liver, spleen, small intestine mucosa, testis, myocardial and skeletal musculature) of cattle].

The substrate that was split most rapidly by acid phosphatase was p-nitrophenylphosphate. Two peaks of activity were obtained at pH 4.6-4.8 and 5.1-5.4. The enzyme remained stable for a long time when refrigerated. It was inhibited strongly by urea and tartrate, and slightly by fluoride and L-phenylalanine. Mercaptoethanol elicited pronounced activation of the enzyme. Four different forms of isoenzyme, giving rise to 11 phenotypes, were identified. A suitable analytical technique was electrophoresis on polyacrylamide gel with phosphate-citrate buffer. Mean activity was 3.15 +/- 0.41 units per gramme of haemoglobin haemolysate. Some of the isoenzyme preparations showed considerable variation in activity. There was no change in enzyme activity after temporary hypomagnesaemia. Acid phosphatase activity was high in testis, kidney and intestinal mucosa; myocardium, liver and spleen showed moderate activity. Five isoenzymes were demonstrable in a starch column and six in PAA gel.