| X-RAY DIFFRACTION |
4.5 |
293 |
CTX-M-14 was produced, purified and crystallized as before, with a slight modification in crystallization conditions to obtain slightly bigger crystals which roughly match the X-ray focal spot. For this purpose, a 50% CTX-M-14 solution (22 mg/ml) was mixed with a 45% precipitant solution (40% PEG8000, 200 mM lithium sulfate, 100 mM sodium acetate, pH 4.5) and with a 5% undiluted seed stock in batch crystallization setups, resulting in crystals with a homogeneous size distribution of 11-15 um after 90 minutes. The crystals were centrifuged at 200xg for 5 min and the supernatant was replaced with a stabilization buffer (28% PEG8000, 140 mM lithium sulfate, 70 mM sodium acetate, pH 4.5) to stop further crystal growth. |
