| X-RAY DIFFRACTION |
7.0 |
? |
THROMBIN WAS PURCHASED FROM HAEMATOLOGIC TECHNOLOGIES, INC. AND ACETYL-HIRUDIN
FROM BACHEM. THROMBIN WAS PREPARED AS DESCRIBED (SKRZPCZAK-JANKUN ET AL., 1991)
.THROMBIN (1.0 MG/ML IN 50 MM HEPES, 50 % GLYCEROL, PH 7.0) WAS INCUBATED
WITH 1.0 MM ACETYL-HIRUDIN, 1.0 MM BABIM, 1.0 MM ZN+2 FOR 1 HR AT 4 DEG C.
GLYCEROL WAS REMOVED AND THE COMPLEX CONCENTRATED WITH A CENTRICON 10 (AMICON)
TO 8.6 MG/ML AS DETERMINED BY THE BIORAD PROTEIN ASSAY KIT USING BOVINE SERUM
ALBUMIN. CRYSTALS OF THROMBIN-ACETYL-HIRUDIN-BABIM-ZN+2 WERE GROWN IN HANGING
DROPS BY VAPOR DIFFUSION AFTER STREAK SEEDING. THE DROPS WERE MADE FROM 5
MICROLITERS OF COMPLEX AND 5 MICROLITERS OF RESERVOIR SOLUTION (0.10 M TRIS,
0.50 M NACL, 22 % (BY VOLUME) PEG 4K, PH 7.00). A CO-CRYSTAL WAS SOAKED IN 30 %
PEG 4K,0.50 M NACL, 0.10 M TRIS, 46 MM ZN+2, PH 7.00, SATURATED IN BABIM AND
CONTAINING 2 % DMSO. |
