   5.1.1.21 | purified recombinant detagged enzyme in apoform, in complex with pyridoxal 5'-phosphate, in complex with N-(5'-phosphopyridoxyl)-L-isoleucine, and in complex with N-(5'-phosphopyridoxyl)-D-allo-isoleucine. By sitting drop vapour diffusion method, for crystals of PLP-bound enzyme, mixing of 0.002 ml enzyme solution containing 0.05 mM PLP 33% 2-propanol, 0.2 M magnesium acetate, 0.1 M cacodylate buffer pH 6.5, for crystals of the apoenzyme mixing of 0.001 ml enzyme solution containing 2 mM D-tert-Leu and 0.1 mM PLP with 0.001 ml of 0.5 M NaCl, 10 mM MgCl2, 10mM hexadecyltrimethylammonium bromide, for crystals of the PLP-L-Ile-bound enzyme, mixing of 0.001 ml protein solution with 0.001 ml of PLP-L-Ile, 20% PEG 3000, 0.2 M NaCl, 0.1 M HEPES, pH 7.5, and for crystals of the PLP-D-allo-Ile-bound enzyme are grown in sitting drops composed of 0.001 ml enzyme solution containing 1 mM PLP-D-allo-Ile mixed with an equal volume of 50 mM cadmium sulfate hydrate, 0.76 M sodium acetate trihydrate, and 0.1 M HEPES, pH 7.5. In all cases, drops are equilibrated against 0.1 ml mother liquor at 20°C, X-ray diffraction structure determination and analysis at resolutions of 2.77 A, 1.94 A, 2.65 A, and 2.12 A, respectively, molecular replacement using with the tetrameric structure of GABA-AT from Sulfolobus tokodaii (PDB ID 2eo5) |
| 5.1.1.21 | purified recombinant His-tagged enzyme alone or in complex with pyridoxal 5'-phosphate, hanging drop vapour diffusion technique, mixing of 0.002 ml of 2-8 mg/ml protein in 50 mM Na-phosphate, pH 7.2, and 0.1 mM 2-mercaptoethanol, with 0.002 ml of reservoir solution containing 12-18% PEG 3350 and 100 mM lithium citrate, 20°C, several weeks, for complex crystals soaking in pyridoxal 5'-phosphate containing mother liquor, X-ray diffraction structure determination and analysis at 2.6 A and 2.15 A resolution, respectively |
