Structural highlights
Function
[BSUHB_THEMA] Phosphatase with broad specificity; it can dephosphorylate fructose 1,6-bisphosphate, both D and L isomers of inositol-1-phosphate (I-1-P) but displaying a 20-fold higher rate of hydrolysis of D-I-1-P than of the L isomer, 2'-AMP, pNPP, inositol-2-phosphate, beta-glycerol phosphate, and alpha-D-glucose-1-phosphate. Cannot hydrolyze glucose-6-phosphate, fructose-6-phosphate, 5'-AMP and NAD(+). May be involved in the biosynthesis of a unique osmolyte, di-myo-inositol 1,1-phosphate.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The structure of the first tetrameric inositol monophosphatase (IMPase) has been solved. This enzyme, from the eubacterium Thermotoga maritima, similarly to its archaeal homologs exhibits dual specificity with both IMPase and fructose-1,6-bisphosphatase activities. The tetrameric structure of this unregulated enzyme is similar, in its quaternary assembly, to the allosterically regulated tetramer of fructose-1,6-bisphosphatase. The individual dimers are similar to the human IMPase. Additionally, the structures of two crystal forms of IMPase show significant differences. In the first crystal form, the tetrameric structure is symmetrical, with the active site loop in each subunit folded into a beta-hairpin conformation. The second form is asymmetrical and shows an unusual structural change. Two of the subunits have the active site loop folded into a beta-hairpin structure, whereas in the remaining two subunits the same loop adopts an alpha-helical conformation.
Crystal structure of the tetrameric inositol 1-phosphate phosphatase (TM1415) from the hyperthermophile, Thermotoga maritima.,Stieglitz KA, Roberts MF, Li W, Stec B FEBS J. 2007 May;274(10):2461-9. Epub 2007 Apr 10. PMID:17419729[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Chen L, Roberts MF. Characterization of a tetrameric inositol monophosphatase from the hyperthermophilic bacterium Thermotoga maritima. Appl Environ Microbiol. 1999 Oct;65(10):4559-67. PMID:10508089
- ↑ Stec B, Yang H, Johnson KA, Chen L, Roberts MF. MJ0109 is an enzyme that is both an inositol monophosphatase and the 'missing' archaeal fructose-1,6-bisphosphatase. Nat Struct Biol. 2000 Nov;7(11):1046-50. PMID:11062561 doi:10.1038/80968
- ↑ Stieglitz KA, Roberts MF, Li W, Stec B. Crystal structure of the tetrameric inositol 1-phosphate phosphatase (TM1415) from the hyperthermophile, Thermotoga maritima. FEBS J. 2007 May;274(10):2461-9. Epub 2007 Apr 10. PMID:17419729 doi:http://dx.doi.org/10.1111/j.0014-2956.2007.05779.x
