Hi Morgan Elizabeth, In some cases adding 1-2% of cryoprotectant into crystallization drop during setting those drops up helps to introduce 25-30% of the same cryoprotectant during harvest, provided you still can get those crystals to grow. Worked for me in several cases.
Vaheh From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> On Behalf Of Blake, Morgan Elizabeth Sent: Wednesday, November 22, 2023 11:44 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] Fragile Crystals Hello! I am a PhD student working on a crystallography project to wrap up my dissertation research. I have purified a complex of two proteins, and I can consistently grow crystals in 10% PEG3350, 0.2M KSCN, 0.1M BIS-TRIS propane pH 7.5. These crystals have sharp edges and can grow to a large size (greater than 0.5 mm), but the crystals seem to be very fragile. When we open the drops to harvest the crystals, we have little time to harvest the crystals before they crack. When we move the crystals to a cryoprotectant, over time they start fracturing. We've tried using different percentages of glycerol, ethylene glycol, PEG400, and oil for cryoprotectants with no success. Needless to say, the crystals do not diffract well, with spot patterns that look very streaky/mosaic, which I presume is due to the defects that we see in harvesting/handling. We have screened for alternate crystallization conditions, but we seem to get the same morphology in other conditions. Does anyone have suggestions for additives we could use post-crystallization to help stabilize our crystals? Thanks for your advice! ________________________________ To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1<https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1> ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
