| X-RAY DIFFRACTION |
5.5 |
281 |
HmdII from Methanocaldococcus jannaschii reconstituted with Fe-guanylylpyridinol cofactor was cocrystallized with methenyl-tetrahydromethanopterin using the sitting drop vapor diffusion method under N2/H2 (95%/5%) in red light condition. 20 mg/ml of reconstituted enzyme in 25 mM Tris pH 7.5, 5% glycerol, 150 mM NaCl, 2 mM DTT and 3 mM methenyl-tetrahydromethanopterin was spotted on a 96-well 2-drop MRC Crystallization Plates (Molecular Dimensions, Suffolk, UK) with a ratio of 0.7 ul of protein and 0.7 ul of reservoir solution. After several weeks, crystals appeared in 2 M LiSO4, 100 mM Sodium acetate pH 5.5, 100 mM MgSO4 and 5% v/v PEG 400. jHmdII crystal was cryoprotected in its mother liquor supplemented with 30% ethylene glycol before freezing in liquid nitrogen. |
