|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 18.104.22.168
Enzymes and Genes:
phytase / 4-phytase ( Triticum aestivum )
inositol monophosphatase 3 : IMPAD1 ( Homo sapiens )
myo-inositol monophosphatase 2 : IMPA2 ( Homo sapiens )
inositol monophosphatase 1 : IMPA1 ( Homo sapiens )
In Pathway: phytate degradation I
Note that this reaction equation differs from the official Enzyme Commission reaction equation for this EC number, which can be found here .
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Mass balance status: Balanced.
Direct generic reaction:
a myo-inositol monophosphate + H2O → myo-inositol + phosphate (22.214.171.124)
Enzyme Commission Primary Name: inositol-phosphate phosphatase
Enzyme Commission Synonyms: 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
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): 7.2170105 [Latendresse13]
Enzyme Commission Summary:
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 [Yoshikawa97].
Instance reaction of [1D-myo-inositol 1,2,3,4,5,6-hexakisphosphate + H2O → a D myo-inositol penta kis phosphate + phosphate] (126.96.36.199):
i7: 1D-myo-inositol 1,2,3,4,5,6-hexakisphosphate + H2O → D-myo-inositol (1,2,3,5,6) pentakisphosphate + phosphate (188.8.131.52)
Instance reactions of [a myo-inositol monophosphate + H2O → myo-inositol + phosphate] (184.108.40.206):
i14: 1D-myo-inositol 3-monophosphate + H2O → myo-inositol + phosphate (220.127.116.11)
i15: 1D-myo-inositol 5-monophosphate + H2O → myo-inositol + phosphate (18.104.22.168)
i16: 1D-myo-inositol 6-monophosphate + H2O → myo-inositol + phosphate (22.214.171.124)
i17: 1D-myo-inositol 2-monophosphate + H2O → myo-inositol + phosphate (126.96.36.199)
i18: 1D-myo-inositol 1-monophosphate + H2O → myo-inositol + phosphate (188.8.131.52)
i19: 1D-myo-inositol 4-monophosphate + H2O → myo-inositol + phosphate (184.108.40.206)
Ackermann87: Ackermann KE, Gish BG, Honchar MP, Sherman WR (1987). "Evidence that inositol 1-phosphate in brain of lithium-treated rats results mainly from phosphatidylinositol metabolism." Biochem J 242(2);517-24. PMID: 3036092
Eisenberg67: Eisenberg F (1967). "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(7);1375-82. PMID: 4290245
Gee88: Gee NS, Ragan CI, Watling KJ, Aspley S, Jackson RG, Reid GG, Gani D, Shute JK (1988). "The purification and properties of myo-inositol monophosphatase from bovine brain." Biochem J 249(3);883-9. PMID: 2833231
Woscholski00: Woscholski, R., Parker, P.J (2000). "Inositol phosphatases: constructive destruction of phosphoinositides and inositol phosphates. In: Cockcroft, S. (Ed.),." Biology of Phosphoinositides, Biology of Phosphoinositides, Oxford,.
Yoshikawa97: Yoshikawa T, Turner G, Esterling LE, Sanders AR, Detera-Wadleigh SD (1997). "A novel human myo-inositol monophosphatase gene, IMP.18p, maps to a susceptibility region for bipolar disorder." Mol Psychiatry 2(5);393-7. PMID: 9322233
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