| X-RAY DIFFRACTION |
7.50 |
293 |
A THREE-FOLD EXCESS OF A
PROPRIETARY FACTOR XA INHIBITOR WITH PICOMOLAR AFFINITY WAS
ADDED TO THE DES-GLA-FACTOR XA. THIS INHIBITOR IS BASED
ON THE SAME TEMPLATE AS XLC IN 1MQ5. THE PROTEIN WAS THEN
CONCENTRATED TO 12-17 MG/ML. CRYSTALS WERE GROWN USING 2 UL
OF COMPLEX WITH 2 UL OF RESERVOIR CONTAINING 15-21% PEG1500
AND 10 MM CACL2. 30-40 UL SITTING DROPS CONTAINING
SATURATED INHIBITOR (5 MM) IN 21% PEG1500, 5 MM CACL2, 50
MM NACL, 50 MM TRIS PH 7.5 (CRYSTAL SOAKING SOLUTION)
WERE EQUILIBRATED OVER A 1 ML RESERVOIR CONTAINING THE
CRYSTAL SOAKING SOLUTION FOR 1 TO 2 DAYS. A SINGLE FACTOR
XA CRYSTAL WAS TRANSFERRED USING A MOUNTED CRYOLOOP INTO ONE
OF THESE SITTING DROPS AND ALLOWED TO SOAK FOR THREE OR MORE
Days. AFTER THE INITIAL SOAK, EACH CRYSTAL WAS THEN
TRANSFERRED TO AN UNUSED DROP AND ALLOWED TO SOAK FOR SECOND
PERIOD OF THREE OR MORE DAYS. pH 7.50, VAPOR DIFFUSION, HANGING DROP, temperature 293K |
