5.4.99.18	hanging-drop method, crystals grow best at 295 K with the optimized mother-liquor conditions of 21-23% PEG 4K, 0.19 M ammonium acetate and 90 mM citrate, pH 5.25-5.5. Crystals belong to space group I422, with unit-cell parameters a = 99.25, c = 164.81 A	660590	
5.4.99.18	hanging-drop vapor-diffusion method, crystals grown in the presence of 4-carboxaminoimidazole ribonucleotide belong to space group P2(1)2(1)2(1), with unit cell parameters a = 86.92, b = 94.55 and c = 149.96 A. The 1.5 A crystal structure reveals an octameric structure with 422 symmetry	663416	
5.4.99.18	multiple REDOR NMR studies of a 151000 Da complex of uniformly 15N-labeled enzyme and the active site ligand [6-13C]-citrate show a single ionization equilibrium associated with the key histidine H59. H59 exists in approximately equimolar amounts of an Ndelta-unprotonated pyridine-like form and an Ndelta-protonated pyrrole-like form. Proton transfer mechanism involves H59 Ndelta	678322	
5.4.99.18	mutant H59N soaked in 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate, protonation of 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate C4 may occur in absence of H59	678203	
5.4.99.18	nanodroplet vapor diffusion method, 1.77 A resolution, unit cell parameters: a = b = 103.25 A, c = 65.45 A, alpha = beta = 90°	663353	
5.4.99.18	purified recombinant detagged enzyme, crystallization at room temperature, 10 mg/ml protein is mixed with a reservoir solution consisting of 0.1 M sodium acetate trihydrate, pH 4.5, and 2 M ammonium sulfate, 24 h, X-ray diffraction structure determination and analysis at 1.45 Aresolution, molecular replacement using the structure of Bacillus anthracis PurE, PDB ID 1xmp, as template	726578	
5.4.99.18	wild-type cocrystallized with 4-nitroaminoimidazole ribonucleotide and mutants H45N and H45Q soaked with 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate	678260