1e0t

R292D mutant of E. coli pyruvate kinase

spinqualitylabelsall models 1e0t, resolution 1.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1e0t is a 4 chain structure with sequence from Ecobb. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: SO4 Related: 1pky, 1e0u Activity: Pyruvate kinase, with EC number 2.7.1.40 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT 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 Pyruvate kinase (PK) is critical for the regulation of the glycolytic pathway. The regulatory properties of Escherichia coli were investigated by mutating six charged residues involved in interdomain salt bridges (Arg(271), Arg(292), Asp(297), and Lys(413)) and in the binding of the allosteric activator (Lys(382) and Arg(431)). Arg(271) and Lys(413) are located at the interface between A and C domains within one subunit. The R271L and K413Q mutant enzymes exhibit altered kinetic properties. In K413Q, there is partial enzyme activation, whereas R271L is characterized by a bias toward the T-state in the allosteric equilibrium. In the T-state, Arg(292) and Asp(297) form an intersubunit salt bridge. The mutants R292D and D297R are totally inactive. The crystal structure of R292D reveals that the mutant enzyme retains the T-state quaternary structure. However, the mutation induces a reorganization of the interface with the creation of a network of interactions similar to that observed in the crystal structures of R-state yeast and M1 PK proteins. Furthermore, in the R292D structure, two loops that are part of the active site are disordered. The K382Q and R431E mutations were designed to probe the binding site for fructose 1, 6-bisphosphate, the allosteric activator. R431E exhibits only slight changes in the regulatory properties. Conversely, K382Q displays a highly altered responsiveness to the activator, suggesting that Lys(382) is involved in both activator binding and allosteric transition mechanism. Taken together, these results support the notion that domain interfaces are critical for the allosteric transition. They couple changes in the tertiary and quaternary structures to alterations in the geometry of the fructose 1, 6-bisphosphate and substrate binding sites. These site-directed mutagenesis data are discussed in the light of the molecular basis for the hereditary nonspherocytic hemolytic anemia, which is caused by mutations in human erythrocyte PK gene. The allosteric regulation of pyruvate kinase.,Valentini G, Chiarelli L, Fortin R, Speranza ML, Galizzi A, Mattevi A J Biol Chem. 2000 Jun 16;275(24):18145-52. PMID:10751408 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Pyruvate Kinase

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