1.3.7.3 | purified substrate-free and -bound wild-type, selenomethionine-labeled enzyme PebB, hanging drop vapor diffusion method, mixing of 0.001 ml of 7 mg/ml protein solution with or without substrate, and 0.001 ml of reservoir solution containing 0.1 M Tris, pH 8.5, 34.5% PEG 3350, and 0.15 M ammonium sulfate, 4 days, 4°C, method optimization, X-ray diffraction structure determination and analysis at 1.90 A and 1.65 A, respectively |