Acid phosphatase synthesis inAspergillus flavus

Abstract

Proteins with phosphatase activity were produced during the growth of Aspergillus flavus in a phosphate-supplemented liquid synthetic medium. The best carbon and nitrogen sources for the synthesis of phosphatase were glucose and ammonium sulfate, respectively. The proteins were separated by molecular exclusion and ion exclusion chromatography (IEC) into three components one of which showed phosphatase activity. The molar mass of the enzyme was approximately 62 kDa. The purified enzyme exhibited an optimum activity at pH 4.0 and at 45 degrees C. The activity of the enzyme was stimulated by Ca2+ and Mg2+ but inhibited by fluoride, iodoacetic acid, ethylenediaminetetraacetic acid and 2,4-dinitrophenol, and exhibited an apparent KM of approximately 420 mumol/L.

Yeast Acid Phosphatases and Phytases: Production, Characterization and Commercial Prospects

“…They are able to perform transphosphorylation reactions from phosphoesters of phenol, p -nitrophenylphosphate and others to various receptors such as glucose and pyridoxine (Guimaraes et al, 2004 ). They have been implicated in translocation mechanisms and regulatory processes involved in sugar metabolism, which may enhance growth (Famurewa and Olutiola, 1994 ). Acid phosphatases are also reported to be involved in signal transduction mediated by phospholipase-D and cell regulation such as the de novo synthesis of glycerolipids, in which a phosphatidic acid phosphatase converts phosphatidic acid into diacylglycerol (Guimaraes et al, 2004 ).…”