I have always wondered what the contribution is from the pH-ing
counter-ions, because the buffers are always, e.g., Tris-Cl or
Na-HEPES. I have often thought it might be more ideal to screen with
TRIS-HEPES as the protein buffer, but probably over the years these
counter-ions have fortuitously aide
Shankar,
I would suggest to also set up a few plates with your protein in HEPES
instead of Tris. I once worked for months trying to improve tiny crystals
while my protein was in Tris, pH 7.4, to no avail. I got beautiful
crystals when I purified my protein in HEPES, pH 7.4, with everything else
Dear all,
Thank you very much for all your helpful comments. I will try them and post
on the BB my results.
Best regards
Shankar
On Wed, Jan 2, 2013 at 11:59 AM, Sankaranarayanan Srinivasan <
texs...@gmail.com> wrote:
> Dear all,
>
> A very happy new year to all.
>
> I would appreciate some ex
Dear Shankar,
I once got crystals with Ethylene glycol as precipitant but at low
concentration (8-14%) and there always had been spots right from the beginning.
It sometimes happens that you get nice looking crystals but they do not
diffract. If you have hits from other conditions may be you sh
Hi Shankar,
I don't claim to be an expert, but I've used ethylene glycol as a
cryoprotectant many times, and 30% (v/v) would probably be sufficient for
proper freezing without any further addition.
Did you try and shoot a crystal at room temperature?
Hth,
Dave
On Jan 2, 2013 5:59 PM, "Sankaranar
Dear Sankaranarayanan Srinivasan
Try replacing both glycerol and ethylene glycol by propylene glycol in part
or completely.
Enrico.
On Wed, 02 Jan 2013 18:59:21 +0100, Sankaranarayanan Srinivasan
wrote:
Dear all,
A very happy new year to all.
I would appreciate some expert advice on op
Dear all,
A very happy new year to all.
I would appreciate some expert advice on optimizing a crystallization
condition in which the initial hits were obtained with ethylene glycol as
the main precipitant. Here is the summary of things tried.
We have a protein, size (31Kda) and the starting prot
