Pyridoxal phosphate phosphatase PHOSPHO2， orphan 2（PHOSPHO2) is a member of the haloacid dehalogenase（HAD) superfamily. Phosphatase has an elevated activity toward phosphoethanolamine（PEA) and phosphocholine（PCho). PHOSPHO 1， a phosphoethanolamine/phosphocholine phosphatase， is upregulated in mineralizing cells and is believed to be implicated in the production of inorganic phosphate for bone mineralization. PHOSPHO2 is a recognized phosphatase sharing a 42% sequence identity with PHOSPHO1. PHOSPHO1 and PHOSPHO2 are especially similar， however surprisingly recombinant PHOSPHO2 hydrolyses phosphoethanolamine and phosphocholine comparatively inadequately.
