Purification and characterization of a heat-stable acid phosphatase from chickpea

Abstract

Acid phosphatases (APases) form a group of enzymes catalyzing hydrolysis of avariety of phosphate esters in the acidic environments. APases are believed to increaseorthophosphate (Pi) availability under phosphorous deficient conditions. The APase fromchickpea was purified by ethanol precipitation, followed by successive chromatographies onDEAE-Cellulose and Sephadex G-150. The enzyme was purified 73-folds. The optimumtemperature and pH for enzyme activity were 50 °C and 5.5, respectively. All metal saltsexcept ZnCl2 and HgCl2 were tolerated and did not adversely affect APase activity. Thepurified enzyme had a lower Km (0.25 mM) and higher Vmax (9 mM) for PNPP. The APase hadbroad substrate specificity with PNPP and natural substrates.