1.14.13.61	purified enzyme, hanging drop vapour diffusion method, 50 mg/ml protein in 10 mM Tris-HCl, pH 8.0, is mixed with reservoir solution, containing 33–35% PEG 400, 200 mM ammonium tartrate, pH 6.5, in a 3:2 ratio with a resulting pH of 7.0, at aerobic conditions, 3 days at 17°C, under anaerobic conditions a reservoir solution containing 29–30% PEG 400, 200 mM ammonium tartrate, 5 mM Na-dithionite, pH 6.5, is mixed with protein reduced by 5 mM Na-dithionite in a ratio of 2:2 at 15°C, X-ray diffraction structure determination and analysis at 2.5 A resolution	677152