Ursula,
After extensive testing, I have found out that in most cases pH changes
during flash freezing does
not pose a problem. In some cases it can be beneficial. I encourage you
to try +/- 2 pH units
from your crystallization pH.
Sometimes a sub-optimal pH is chosen just because the cryst
Von: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] Im Auftrag von Ursula
Schulze-Gahmen
Gesendet: Freitag, 12. Juni 2015 22:47
An: CCP4BB@JISCMAIL.AC.UK
Betreff: [ccp4bb] Tris buffer in cryo protectant
Does anyone have experience with Tris buffer in cryo protectants? I would
expect the pH
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
L
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
