4.1.3.38 purified recombinant detagged enzyme, hanging drop vapour diffusion method, mixing of 0.001 ml of 33 mg/mL prrotein in 100 mM HEPES, pH 7.5, 500 mM NaCl, 0.1 mM pyridoxal 5'-phosphate, and 10 mM 4-aminobenzoate, with 0001 ml of reservoir solution containing 10% w/v PEG 400, 1.8 M ammonium sulfate and 100 mM MES, pH 6.5, 20°C, 1 week, X-ray diffraction structure dtermination and analysis at 1.75 A resolution 4.1.3.38 purified recombinant selenomethionine-labeled enzyme and of purified recombinant wild-type enzyme in complex with cofactor pyridoxal 5'-phosphate, hanging drop vapor diffusion method, mixing of 0.001 ml of 10 mg/ml protein in 100 mM NaCl, 20 mM Tris-Cl, pH 8.0, with an equal volume of reservoir solution containing 20% w/v PEG monomethyl ether 5000, 0.1 M Bis-Tris, pH 6.2, 1-2 days to 1 week, 16°C, X-ray diffraction structure determination and analysis at 1.90-2.20 A resolution 4.1.3.38 sitting drop vapor diffusion method, using 0.1 M HEPES buffer pH 8.0 containing 1.3 M Li2SO4 and 2% (v/v) PEG 200 4.1.3.38 small yellow prisms crystals in the unliganded form obtained using the sparse-matrix method along with the hanging-drop vapor-difussion method