-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Dear Ursula,
unless it is too long a list, maybe you could list the cryo-protectants you have used so far? Did you try sugars (e.g. glucose), or Na Malonate, or Butanediol (either 2,5 or 1,6, I don't remember exactly)? You could also increase the protein or NaCl concentration a little and decrease the temperature to 10 degrees, say, for crystallisation, then to 4 degrees to harvesting. But first I would try as Jacob suggested, collect at room temperature in a capillary. It's a very gentle treatment for crystals (except for the X-rays ;-) ). When you transfer the crystal with a pipet and the capillary, it is never exposed to air and you can work in the cold room to stabilise the temperature. Regards, Tim On 03/02/2015 07:49 PM, Ursula Schulze-Gahmen wrote: > I know there was jut recently a discussion about cryoconditions > for crystals, but I am still hoping for some new ideas for my > crystals that grow from HEPES buffer pH 7.3, 0.2 M NaCl by slowly > lowering the temperature from 20 to 4 degrees. > > These crystals are easy to grow but extremely sensitive to > temperature change, and any of the usual cryo reagents tested so > far simply dissolve the crystals. I am n ot sure how I could > counteract the solubilizing effect of glycerol or ethylen glycol, > since there is no precipitant concentration that I could increase > to stabilize the crystals. Paratone didn't work either so far. > > Any other ideas for these low salt crystals? > > Ursula > - -- - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iD8DBQFU9LrfUxlJ7aRr7hoRAg0UAJ0fZJScgnGNWNOAHS00ec4f6kJmIACffBQB Vm/WTDjFC5J+OKtGPfEYbpo= =lw4r -----END PGP SIGNATURE-----
