Phosphatase, Acid from sweet potato

Potato acid phosphatase is used as a dephosphorylating reagent in thiochrome assays for the detection of thiamin in biological samples. In this assay, it was shown to be more effective than acid phosphatases from wheat germ or α-amylase.

Sweet potato acid phosphatase has been used in a study as a pre-column enzyme reactor via a covalent bond with glutaraldehyde and aminopropyl controlled-pore glass. It has also been used in a study to investigate the use of tyrosine, histidine, and cysteine as ligands for Mn(III) in sweet potato phosphatase.

Acid phosphatases (APase) are a family of enzymes that non-specifically catalyze the hydrolysis of monoesters and anhydrides of phosphoric acid to produce inorganic phosphate at an optimum pH of 4 to 7 by the following reaction: APaseR-PO₄ + H₂O --------------- R-OH + HOPO₃ ²⁺Their function in the production, transport, and recycling of phosphate is critical for the metabolic and energy transduction processes of the cell. As a group, Apases may be as important as kinases in regulatory processes.

Acid phosphatase from sweet potato is a phosphomonoesterase, which can appear in multiple molecular forms of similar molecular mass but with different isoelectric points.

One unit will hydrolyze 1.0 μmole of p-nitrophenyl phosphate per min at pH 4.8 at 37 °C.

Suspension in 1.8 M (NH₄)₂SO₄, 10 mM MgCl₂, pH 5.3