| X-RAY DIFFRACTION |
6.5 |
277 |
MAVDHFR (15 MG/ML) IN 20 MM HEPES (PH 7.0), 1 MM DTT, 0.1 MM EDTA, 1.5 MM NAN3 WAS MIXED WITH NADPH (3 MM, 15 MIN AT ROOM TEMPERATURE) AND THEN TRIMETHOPRIM (2 MM, 15 MIN ON ICE). CRYSTALLIZATION (HANGING DROP VAPOR PHASE EQUILIBRATION) WAS ACHIEVED BY MIXING WITH AN EQUAL VOLUME OF THE PROTEIN COMPLEX WITH A RESERVOIR SOLUTION CONSISTING OF 70% 2-METHYL-2, 4-PENTANEDIOL (MPD) AND 100 MM HEPES (PH 6.5), AND SUSPENDING THE MIXTURE OVER THE RESERVOIR AT 277 K. SMALL ROD-LIKE CRYSTALS (0.01 X 0.01 X 0.05 MM) GREW WITHIN 2 DAYS. CRYSTALS WERE FLASH-COOLED DIRECTLY FROM THE DROP IN LIQUID N2. |
