Hi all, A non CCP4 question, the cryo diffraction without protein crystal had absolutely no ice ring. But when I transferred protein crystal from the sitting drop to the cryo, there was ice ring in diffraction pattern.
My doubt is whether water shelled around the crystal led to this ice ring, and how to remove it? Actually siiting drop was set in microbatch plate layered with around 2.5 ml paraffin oil. Was this oil anyway responsible for this water shell to be kapt on the crystal? Crystallization condition: 20% Jeffamine M-600, 0.1M HEPES (pH 7.5). Cryo condition: 20% Jeffamine M-600, 0.1M HEPES (pH 7.5), 15% glycerol. Regards, Arpita. --- Arpita Goswami Junior Research Fellow Structural Biology Laboratory Centre for DNA Fingerprinting and Diagnostics (CDFD) Hyderabad