2ffr

Crystallographic studies on N-azido-beta-D-glucopyranosylamine, an inhibitor of glycogen phosphorylase: comparison with N-acetyl-beta-D-glucopyranosylamineCrystallographic studies on N-azido-beta-D-glucopyranosylamine, an inhibitor of glycogen phosphorylase: comparison with N-acetyl-beta-D-glucopyranosylamine

Structural highlights 2ffr is a 1 chain structure with sequence from Oryctolagus cuniculus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.03Å Ligands: , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function PYGM_RABIT Phosphorylase is an important allosteric enzyme in carbohydrate metabolism. Enzymes from different sources differ in their regulatory mechanisms and in their natural substrates. However, all known phosphorylases share catalytic and structural properties. 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 N-acetyl-beta-D-glucopyranosylamine (NAG) is a potent inhibitor (Ki=32 microM) of glycogen phosphorylase b (GPb), and has been employed as a lead compound for the structure-based design of new analogues, in an effort to utilize its potential as a hypoglycaemic agent. Replacement of the acetamido group by azidoacetamido group resulted in an inhibitor, N-azidoacetyl-beta-D-glucopyranosylamine (azido-NAG), with a Ki value of 48.7 microM, in the direction of glycogen synthesis. In order to elucidate the mechanism of inhibition, we determined the ligand structure in complex with GPb at 2.03 A resolution, and the structure of the fully acetylated derivative in the free form. The molecular packing of the latter is stabilized by a number of bifurcated hydrogen bonds of which the one involving a bifurcated C-H...N...H-C type hydrogen bonding is rather unique in organic azides. Azido-NAG can be accommodated in the catalytic site of T-state GPb at approximately the same position as that of NAG and stabilizes the T-state conformation of the 280 s loop by making several favourable contacts to residues of this loop. The difference observed in the Ki values of the two analogues can be interpreted in terms of desolvation effects, subtle structural changes of protein residues and changes in water structure. Crystallographic studies on N-azidoacetyl-beta-D-glucopyranosylamine, an inhibitor of glycogen phosphorylase: comparison with N-acetyl-beta-D-glucopyranosylamine.,Petsalakis EI, Chrysina ED, Tiraidis C, Hadjiloi T, Leonidas DD, Oikonomakos NG, Aich U, Varghese B, Loganathan D Bioorg Med Chem. 2006 Aug 1;14(15):5316-24. Epub 2006 Apr 17. PMID:16616506 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Glycogen phosphorylase 3D structures

spinqualitylabelsall models 2ffr, resolution 2.03Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image