Purification and properties of an acid phosphatase from Entamoeba histolytica HM-1 : IMSS

Entamoeba histolytica contains and secretes acid phosphatase, which has bee n proposed as a virulence factor in some pathogenic microorganisms. In this work, we purified and characterised a membrane-bound acid phosphatase (MAP ) from E. histolytica HM-1:IMSS and studied the effect of different chemica l compounds on the secreted acid phosphatase and MAP activities. MAP purifi cation was accomplished by detergent solubilisation, and affinity and ion e xchange chromatographies. The enzyme showed a pi of 5.5-6.2, an optimum pH of 5.5, and a Km value of 1.14 mM with p-nitrophenyl phosphate. (C) 2000 Pu blished by Elsevier Science Ltd on behalf of the Australian Society for Par asitology Inc. All rights reserved.