ACPP, also known as Acid phosphatase, prostate. ACPP is a non-specific tyrosine phosphatase that dephosphorylates a diverse number of ubstrates under acidic conditions (pH 4-6) including alkyl, aryl, and acyl orthophosphate monoesters and phosphorylated proteins. It has lipid phosphatase activity and inactivates lysophosphatidic acid in seminal plasma. Recombinant human ACPP, fused to His-tag at N-terminus, was expressed in E.coli.