phosphoethanolamine/phosphocholine phosphatase (PHOSPHO1)

Function

• phosphatase (phosphomonoesterase)
• high activity toward phosphoethanolamine & phosphocholine
• generation of inorganic phosphate for bone mineralization

O-phosphoethanolamine + H2O <--> ethanolamine + phosphate

Phosphocholine + H2O <--> choline + phosphate

Cofactor: Mg+2

Kinetic parameters:

• KM=3 uM for phosphoethanolamine;
• KM=11.4 uM for phosphocholine
• Optimum pH is 6.7

Expression

• expressed at sites of mineralization in bone & cartilage
• highly expressed in osteoblast cell line SaOS-2 which produces a mineralized matrix, but not in MG-63 cell line, which do not mineralize

More general terms

• phosphomonoesterase

Database

• UniProt: http://www.uniprot.org/uniprot/Q8TCT1.html