| X-RAY DIFFRACTION |
5.5 |
293.15 |
The purified enzyme in 50 mM Tris/HCl pH 8.0, 300 mM NaCl, 2 mM dithionite was crystallized at 8 mg.ml-1. Crystallization was performed anaerobically in a tent containing 100 % N2 atmosphere. Crystals were obtained by initial screening at 20 degree Celsius on 96-Well MRC 2-drop crystallization plates in polystyrene (SWISSCI) containing 90 ul of crystallization solution in the reservoir. The protein sample (0.5 ul) was mixed with 0.5 ul reservoir solution. The reservoir solution contained 25 % w/v Polyethylene glycol 3,350, 100 mM BIS-TRIS at pH 5.5, and 200 mM Lithium sulfate. The plate was then incubated in a Coy tent (N2/H2, 97:3) at 20 degree Celsius. Crystals appeared after a few weeks and were soaked in the crystallization solution supplemented with 15 % v/v glycerol as a cryo-protectant before being frozen in liquid nitrogen. |