EC Number   |
Reference |
|---|
   2.3.1.4 | crystal structures of HsGNA1 in its apo form, complexed with GlcN6P, and the E156A mutant are solved and refined to 2.7 A, 2.3 A and 2.0 A resolution, respectively. Results reveal new features of the GlcN6P binding in HsGNA1. The conserved charge distribution at the GlcN6P binding pocket is important for the acceptor substrate affinity. Glu156, a conserved residue present in GNA1 from various eukaryotic organisms, plays an important role in both the catalytic reaction and substrate affinity. Moreover, the GlcN6P binds to GNA1 without the help of AcCoA binding, suggesting that a pseudo-substrate could bind GNA1 as an inhibitor without the help of AcCoA |
686767 |
| 2.3.1.4 | crystal structures of human and Aspergillus fumigatus GNA1 are determined: structural differences between the two enzymes are mostly located to the sugar-binding site, whereas the AcCoA-binding site is more conserved. These changes affect not only the electrostatics, but also reveal a more spacious sugar binding site in the Aspergillus fumigatus GNA1 enzyme, whereas large side chains at these positions create a tighter pocket in the HsGNA1 enzyme |
685012 |
| 2.3.1.4 | hanging-drop vapour-diffusion method. The crystal diffract to better than 2.6 A resolution and belong to space group P4(1)2(1)2 or P4(3)2(1)2. The unit-cell parameters are a = b = 50.08, c = 142.88 A |
671094 |
| 2.3.1.4 | to 1.5 A resolution. The centre of the protein is a five-stranded beta-sheet, of which four strands are antiparallel-oriented |
718794 |
| 2.3.1.4 | to 1.86 A resolution |
719382 |
| 2.3.1.4 | using the pseudo-substrate glucose-6-phosphate as a probe with GNA1 crystals, the first GNAT (pseudo-)Michaelis complex is trapped. The complex shows optimal alignment under the ideal Burgi-Dunitz angle for direct nucleophilic attack of the sugar amine, and suggests protonation of the tetrahedral intermediate may proceed through intramolecular proton transfer facilitated by a favourably positioned backbone carbonyl. The hydrogen bond established between the hydroxyl group of Tyr174 and the thioester sulfur increase the electrophilic character of the carbonyl group, favouring the direct nucleophilic attack by the glucosamine 6-phosphate, explaining the 500fold decrease in the turnover when Tyr174 is mutated to Phe, providing direct evidence for the nucleophilic attack of the substrate amine, and giving insight into the protonation of the thiolate leaving group |
686750 |
