1fpe
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STRUCTURAL ASPECTS OF THE ALLOSTERIC INHIBITION OF FRUCTOSE-1,6-BISPHOSPHATASE BY AMP: THE BINDING OF BOTH THE SUBSTRATE ANALOGUE 2,5-ANHYDRO-D-GLUCITOL-1,6-BISPHOSPHATE AND CATALYTIC METAL IONS MONITORED BY X-RAY CRYSTALLOGRAPHY
OverviewOverview
The crystal structures of the T form pig kidney, fructose-1,6-bisphosphatase (EC 3.1.3.11) complexed with AMP, the, substrate analogue 2,5-anhydro-D-glucitol 1,6-bisphosphate (AhG-1,6-P2), and Mn2+ at concentrations of 5, 15, 100, and 300 microM have been, determined and refined at resolutions of 2.1-2.3 A to R factors which, range from 0.180 to 0.195, respectively. Two metal ions per active site, have been identified, one at a binding site of high affinity (metal site, 1'), the second in a low affinity site (metal site 2'). The 1-phosphate, group of the substrate analogue coordinates to the metal ion at site 1', but not at site 2'. In these four complexes, the distances between the two, metal ions are all within 0.2 A of 4.3 A. In the previously determined R, form structure of Fru-1,6-Pase complexed with AhG-1,6-P2 and Mn2+, there, are also two metal ions in the active site at metal sites 1 and 2. The, metal ion at site 1 is only 0.6 A displaced from the metal ion at site 1', in the T form and is also coordinated to the 1-phosphate group of, AhG-1,6-P2. However, the second metal ion is located in two distinct sites, which are 1.4 A apart in the T and R form structures. In the R form the, Mn2+ at site 2 is coordinated to the 1-phosphate group of the substrate, analogue. This metal ion is apparently required to orient the phosphate, group for nucleophilic attack at the phosphorus center.(ABSTRACT TRUNCATED, AT 250 WORDS)
About this StructureAbout this Structure
1FPE is a Single protein structure of sequence from Sus scrofa with MN, AHG and AMP as ligands. Active as Fructose-bisphosphatase, with EC number 3.1.3.11 Full crystallographic information is available from OCA.
ReferenceReference
Structural aspects of the allosteric inhibition of fructose-1,6-bisphosphatase by AMP: the binding of both the substrate analogue 2,5-anhydro-D-glucitol 1,6-bisphosphate and catalytic metal ions monitored by X-ray crystallography., Villeret V, Huang S, Zhang Y, Lipscomb WN, Biochemistry. 1995 Apr 4;34(13):4307-15. PMID:7703244
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