Partial purification and some biochemical properties of acid phosphatase in germinating chickpea (Cicer arietinum) seeds

An acid phosphatase (EC 3.1.3.2.) from the embryonic axes of chickpea seeds (Cicer arietinum L. cv. Castellana) was purified by ammonium sulphate precipitation, chromatography on Sephacryl S-200 and polyacrylamide gel electrophoresis. The preparation has an apparent molecular weight of 39 kDa, pH optimum for p-nitrophenylphosphate hydrolysis of 5.25, and Km of 0.57 mM. The enzyme hydrolyzed all the mono- and di-phosphorylated sugars tested, but had no effect on ATP, ADP, AMP and phosphoenolpyruvate. Phosphate was a competitive inhibitor. Mg2+. Ca2+, Hg2+, Fe3+, arsenate, K+ and Zn2+ were inhibitory. Mn2+, dithiothreitol and EDTA had no effect, and polyamines were activators.