| X-RAY DIFFRACTION |
6 |
293 |
Mpro was thawed and diluted to 6 mg/ml using 20 mM Hepes pH 7.5, 50 mM NaCl. GM4 was diluted into the protein solution to a final concentration of 10 mM and allowed to incubate for two hours at room temperature prior to dispensing plates. The drop composition was 0.15 ul protein ligand solution, 0.3 ul 11% (v/v) PEG 4K, 0.1 M MES pH 6.5, and 0.05 ul Mpro crystal seed stock. The Mpro crystal seed stock was prepared by crushing Mpro crystals with a pipette tip, suspending them in 30% PEG 4K, 5% (v/v) DMSO, 0.1 M MES pH 6.5, and vortexing for 60 s with approximately 10 glass beads (1.0 mm diameter, BioSpec products). Reservoir solution was 11% (v/v) PEG 4K, 5% (v/v) DMSO, 0.1 M MES pH 6.5. Crystals were grown using the sitting drop vapor diffusion method at 20 C and appeared within 24 hours, reaching full size within 36 hours. Crystals were looped after one week. |
