| X-RAY DIFFRACTION |
8.5 |
291 |
Proteins were dialyzed in a buffer of 10 mM Tris-HCl, pH 8.5, 1 mM DTT and concentrated to 10 mg/mL. Inhibitor, Ac-DEVD-CMK reconstituted in DMSO, was then added at a 5:1 inhibitor:peptide ratio (w/w). The protein was diluted to a concentration of 8 mg/mL by adding 10 mM Tris-HCl, pH 8.5, concentrated DTT, and concentrated NaN3 so that the final buffer consisted of 10 mM Tris-HCl, pH 8.5, 10 mM DTT, and 3 mM NaN3. Crystals were obtained at 291K by the hanging drop vapor diffusion method using 4 uL drops that contained equal volumes of protein and reservoir solutions over a 0.5 mL reservoir. The reservoir solutions for optimal crystal growth consisted of 100 mM sodium citrate, pH 5.0, 3 mM NaN3, 10 mM DTT, and 10% 16% PEG 6000 (w/v). Crystals appeared within 3.5 to 6 weeks for all mutants, VAPOR DIFFUSION, HANGING DROP |
