IUBMB Enzyme Nomenclature


Accepted name: inositol-phosphate phosphatase

Reaction: myo-inositol phosphate + H2O = myo-inositol + phosphate

For diagram click here.

Other name(s): myo-inositol-1(or 4)-monophosphatase; inositol 1-phosphatase; L-myo-inositol-1-phosphate phosphatase; myo-inositol 1-phosphatase; inositol phosphatase; inositol monophosphate phosphatase; inositol-1(or 4)-monophosphatase; myo-inositol-1(or 4)-phosphate phosphohydrolase; myo-inositol monophosphatase; myo-inositol-1-phosphatase

Systematic name: myo-inositol-phosphate phosphohydrolase

Comments: Acts on five of the six isomers of myo-inositol phosphate, all except myo-inositol 2-phosphate, but does not act on myo-inositol bearing more than one phosphate group. It also acts on adenosine 2'-phosphate (but not the 3'- or 5'- phosphates), sn-glycerol 3-phosphate and glycerol 2-phosphate. Two isoforms are known [4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37184-63-7


1. Eisenberg, F., Jr. D-Myoinositol 1-phosphate as product of cyclization of glucose 6-phosphate and substrate for a specific phosphatase in rat testis. J. Biol. Chem. 242 (1967) 1375-1382. [PMID: 4290245]

2. Gee, N.S., Ragan, C.I., Watling, K.J., Aspley, S., Jackson, R.G., Reid, G.G., Gani, D. and Shute, J.K. The purification and properties of myo-inositol monophosphatase from bovine brain. Biochem. J. 249 (1988) 883-889. [PMID: 2833231]

3. Hallcher, L.M. and Sherman, W.R. The effects of lithium ion and other agents on the activity of myo-inositol-1-phosphatase from bovine brain. J. Biol. Chem. 255 (1980) 10896-10901. [PMID: 6253491]

4. Yoshikawa, T., Turner, G., Esterling, L.E., Sanders, A.R. and Detera-Wadleigh, S.D. A novel human myo-inositol monophosphatase gene, IMP.18p, maps to a susceptibility region for bipolar disorder. Mol. Psychiatry 2 (1997) 393-397. [PMID: 9322233]

5. Woscholski, R. and Parker, P.J. Inositol phosphatases: constructive destruction of phosphoinositides and inositol phosphates. In: Cockcroft, S. (Ed.), Biology of Phosphoinositides, Oxford University Press, Oxford, 2000, pp. 320-338.

6. Ackermann, K.E., Gish, B.G., Honchar, M.P. and Sherman, W.R. Evidence that inositol 1-phosphate in brain of lithium-treated rats results mainly from phosphatidylinositol metabolism. Biochem. J. 242 (1987) 517-524. [PMID: 3036092]

[EC created 1972, modified 1990, modified 2002, modified 2004]

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