Properties of Acetone Insensitive Phosphatase from Ascites Hepatoma of Rat

Abstract

1. The properties of the enzymatic hydrolysis of phosphoethanolamine were examined with the enzyme partially purified from AH 130 ascites hepatoma of rat.
2. From its pH optimum and experiments on various activators and inhibitors, it was concluded that the enzyme is the same as non-specific alkaline phosphatase.
3. The effect of various organic solvents on the activity was investigated. It was found that the hydrolysis of phosphoethanolamine was activated by several organic solvents, but that the hydrolysis of β-glycerophosphate was markedly suppressed by all solvents examined.
4. Partially purified alkaline phosphatases from regenerating liver and normal liver of rat behaved similarly to enzyme from hepatoma cells in the presence of acetone.
5. The difference between normal liver, and regenerating liver and tumour cells of rat in the, reaction of formation of ethanolamine (1-3) was discussed from the results described above.
The authors wish to thank Prof. S. Akabori of the Institute for Protein Research, Osaka University, and Prof. Y. Sakamoto of this Institute and Drs. A. Oikawa and T. Matsushima of National Cancer Center Research Institute for their continuous encouragement and sympathetic interest in this work. Thanks are also due to Miss T. Miyaji for her skilled technical assistance.