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
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> On 13 Jun 2015, at 6:49 am, Ursula Schulze-Gahmen <[log in to unmask]> 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
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