EC Number   |
|---|
    6.3.5.5 | - |
| 6.3.5.5 | C248D mutant of small subunit, crystals are grown at 4°C by batch from 8% poly(ethylene glycol) 8000, 0.65 M tetraethylammonium chloride, 0.5 mM MnCl2, 100 mM KCl, 1.5 mM ADP, 25 mM GEPES, pH 7.4, 0.5 mM L-Orn. The crystals belong to the space group P2(1)2(1)2(1) with unit cell dimensions of a = 151.1 A, b = 164.2 A, and c = 331.5A and one complete (alphabeta)4-heeterotetramer per asymmetric unit |
| 6.3.5.5 | in presence of both IMP and ornithine, structural analysis of the nucleotide monophosphate allosteric binding site for enzyme |
| 6.3.5.5 | molecular dynamics simulation. Carbamate, the product of the reaction involving ATP, bicarbonate, and ammonia, must be delivered from the site of formation to the site of utilization by traveling nearly 40 A within the enzyme. The tunnel is composed of three continuous water pockets and two narrow connecting parts, near residues A23 and G575. The two narrow parts render two free energy barriers of 6.7 and 8.4 kcal/mol, respectively. Three water pockets are filled with about 21, 9, and 9 waters, respectively, and the corresponding relative free energies of carbamate residing in these free energy minima are 5.8, 0, and 1.6 kcal/mol, respectively. The release of phosphate into solution at the site for the formation of carbamate allows the side chain of R306 to rotate toward E25, E383, and E604. This rotation is virtually prohibited by a barrier of at least 23 kcal/mol when phosphate remains bound. This conformational change not only opens the entrance of the tunnel but also shields the charge-charge repulsion from the three glutamate residues when carbamate passes through the tunnel |
| 6.3.5.5 | the structure of enzyme cocrystallized in the presence of the 5-adenylylimidodiphosphate, is determined to 2.1 A by X-ray crystallographic analysis, the three active sites of enzyme communicate via domain movements, the first example of such a domain movement is described |
| 6.3.5.5 | the three active sites within the alpha,beta heterodimer are separated by a linear distance of nearly 100 A and are interconnected by two molecular tunnels |
| 6.3.5.5 | X-ray crystallographic analysis, the three active sites on the protein are widely separated from one another |
| 6.3.5.5 | X-ray crystallographic structure |
