3.4.17.13 | purified recombinant wild-type enzyme and mutants S115A and H285A, sitting drop vapour diffusion method, 0.004 ml of 6 mg/ml protein containing solution is mixed with an equal volume of reservoir solution containing 20 mM CaCl2 dihydrate, 0.1 M sodium acetate trihydrate, pH 4.6, and 30% v/v 2-methyl-2,4-pentanediol, room temperature, 6 mg/ml selenomethionine-labeled enzyme from 50 mM citric acid, pH 4.5, 21°C, X-ray diffraction structure determination and analysis at 1.5-2.4 A resolution |