1c8l

SYNERGISTIC INHIBITION OF GLYCOGEN PHOSPHORYLASE A BY A POTENTIAL ANTIDIABETIC DRUG AND CAFFEINESYNERGISTIC INHIBITION OF GLYCOGEN PHOSPHORYLASE A BY A POTENTIAL ANTIDIABETIC DRUG AND CAFFEINE

Structural highlights 1c8l 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 2.3Å 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 Caffeine, an allosteric inhibitor of glycogen phosphorylase a (GPa), has been shown to act synergistically with the potential antidiabetic drug (-)(S)-3-isopropyl 4-(2-chlorophenyl)-1,4-dihydro-1-ethyl-2-methyl-pyridine-3,5,6-tricarboxyl ate (W1807). The structure of GPa complexed with caffeine and W1807 has been determined at 100K to 2.3 A resolution, and refined to a crystallographic R value of 0.210 (Rfree = 0.257). The complex structure provides a rationale to understand the structural basis of the synergistic inhibition between W1807 and caffeine. W1807 binds tightly at the allosteric site, and induces substantial conformational changes both in the vicinity of the allosteric site and the subunit interface which transform GPa to the T'-like state conformation already observed with GPa-glucose-W1807 complex. A disordering of the N-terminal tail occurs, while the loop of polypeptide chain containing residues 192-196 and residues 43'-49', from the symmetry related subunit, shift to accommodate W1807. Caffeine binds at the purine inhibitor site by intercalating between the two aromatic rings of Phe285 and Tyr613 and stabilises the location of the 280s loop in the T state conformation. Structural basis of the synergistic inhibition of glycogen phosphorylase a by caffeine and a potential antidiabetic drug.,Tsitsanou KE, Skamnaki VT, Oikonomakos NG Arch Biochem Biophys. 2000 Dec 15;384(2):245-54. PMID:11368311 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Glycogen phosphorylase 3D structures

spinqualitylabelsall models 1c8l, resolution 2.30Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image