Might be worth trying to see if your protein will still crystallize in a mixture of tris and TAPS buffer? The pKa of the latter is very close to tris, but goes in the opposite direction with temperature - a roughly 3:2 TAPS:tris mix should have minimal pH change on freezing.
Tristan Croll Lecturer Faculty of Health School of Biomedical Sciences Institute of Health and Biomedical Engineering Queensland University of Technology 60 Musk Ave Kelvin Grove QLD 4059 Australia +61 7 3138 6443 This email and its attachments (if any) contain confidential information intended for use by the addressee and may be privileged. We do not waive any confidentiality, privilege or copyright associated with the email or the attachments. If you are not the intended addressee, you must not use, transmit, disclose or copy the email or any attachments. If you receive this email by mistake, please notify the sender immediately and delete the original email. > On 13 Jun 2015, at 6:49 am, Ursula Schulze-Gahmen <uschulze-gah...@lbl.gov> > wrote: > > Does anyone have experience with Tris buffer in cryo protectants? I would > expect the pH of the cryosolution to increase a lot during flash freezing > which could perhaps destroy the diffraction. I rarely use Tris for > crystallization but the current protein really prefers Tris. I would > appreciate any comments. > > Ursula > > -- > Ursula Schulze-Gahmen, Ph.D. > Project Scientist > UC Berkeley, QB3 > 360 Stanley Hall #3220 > Berkeley, CA 94720-3220 > (510) 643 9491
