EC 3.1.3.74     
Accepted name: pyridoxal phosphatase
Reaction: pyridoxal 5′-phosphate + H2O = pyridoxal + phosphate
Other name(s): vitamine B6 (pyridoxine) phosphatase; PLP phosphatase; vitamin B6-phosphate phosphatase; PNP phosphatase
Systematic name: pyridoxal-5′-phosphate phosphohydrolase
Comments: Requires Mg2+. This enzyme is specific for phosphorylated vitamin B6 compounds: it acts not only on pyridoxal phosphate (PLP), but also on pyridoxine phosphate (PNP), pyridoxamine phosphate (PMP), 4-pyridoxic acid phosphate and 4-deoxypyridoxine phosphate. This reaction can also be carried out by EC 3.1.3.1 (alkaline phosphatase) and EC 3.1.3.2 (acid phosphatase), but these enzymes have very broad substrate specificities.
References:
1.  Fonda, M.L. Purification and characterization of vitamin B6-phosphate phosphatase from human erythrocytes. J. Biol. Chem. 267 (1992) 15978–15983. [PMID: 1322411]
2.  Fonda, M.L. and Zhang, Y.N. Kinetic mechanism and divalent metal activation of human erythrocyte pyridoxal phosphatase. Arch. Biochem. Biophys. 320 (1995) 345–352. [PMID: 7625842]
3.  Jang, Y.M., Kim, D.W., Kang, T.C., Won, M.H., Baek, N.I., Moon, B.J., Choi, S.Y. and Kwon, O.S. Human pyridoxal phosphatase. Molecular cloning, functional expression, and tissue distribution. J. Biol. Chem. 278 (2003) 50040–50046. [PMID: 14522954]
[EC 3.1.3.74 created 2004]