Hi Fred and Zhiyi,
the EMBL and ESRF have also developed a dehydration device that can
also be used for room temperature data collection, see the website here:
http://www.esrf.fr/UsersAndScience/Experiments/MX/About_our_beamlines/ID14-2/HC1b
http://scripts.iucr.org/cgi-bin/paper?S0907444909037822
Cheers, Matt.
Frederic VELLIEUX wrote:
Hi Zhiyi,
There are two ways you can go about this (RT data collection). Either mount the
crystals in capillaries (not all beam lines at synchrotrons have sufficient
space on the goniometer setup to allow data collection on capillary-mounted
crystals) or use a Humidifier (the latter is briefly discussed, for example, on
web page
http://www.esrf.eu/UsersAndScience/Experiments/MX/Cryobench/Instruments/microspec
).
If nothing is done, the crystals will rapidly dry up and "die".
Fred.
Message du 27/01/10 08:53
De : "Zhiyi Wei"
A : CCP4BB@JISCMAIL.AC.UK
Copie à :
Objet : Re: [ccp4bb] Crystal rescue
Thanks for so many quick responses!
Actually, I have test several different cryo-protectants, including
glycerol, EG, and PEG400. I did not see much differences between these
cryo conditions. So, I choose glycerol.
I would like to test my crystals in RT. But I don't know how to do
this. Just mount crystal to the X-ray machine without cryo stream? Or
I should use capillaries?
Zhiyi
On Wed, Jan 27, 2010 at 5:45 AM, Kelly Daughtry wrote:
Tascimate can be used as the cryo as well. I have had experience with
crystals in similar condition and moved the crystals to a 20%
increased Tascimate solution and they froze well.
I agree with Ezra, room temperature mount your crystal before
freezing. It is the only way to know the true problem.
Kelly
*******************************************************
Kelly Daughtry
PhD Candidate
Department of Physiology and Biophysics
Boston University School of Medicine
590 Commonwealth Ave
R 390
Boston MA, 02215
(P) 617-358-5548
*******************************************************
On Tue, Jan 26, 2010 at 1:25 PM, Marcus Winter
wrote:
Dear Zhiyi,
Ezra is exactly right, of course. The Oxford Diffraction PX Scanner
system can assess the diffraction qualities of (putative) protein
crystals in situ - in the crystallisation plate. So, directly, you
would discover if your 'big and beautiful' crystals actually diffract
well... in their mother liquor under ambient conditions and before the
addition of any cryo-protect. Do you have a friend or neighbour with
a PX Scanner ? If not, please feel most welcome to contact
Oxford Diffraction: we would be pleased to assist if at all possible.
Good Luck and Best Wishes,
Marcus Winter.
www.oxford-diffraction.com
-----Original Message-----
From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of
Ezra Peisach
Sent: 26 January 2010 16:01
To: CCP4BB@JISCMAIL.AC.UK
Subject: Re: [ccp4bb] Crystal rescue
First you need to establish if it is your cryo conditions or the
crystals. Depending where you are - they might have the equipment to do
a wet mount - without freezing. Yes the crystal will not last - but
then you know if the problem is in the
crystal. If it is - you need better crystals. If it is the cryo - you
need to work on that. Tacsimate is mixture of alot of different
compounds - but the smears are too close together to be a small salt
crystal on top...
Good luck,
Ezra
On 1/26/2010 10:42 AM, Zhiyi Wei wrote:
Dear all,
I got a problem with my crystals. I have two total different proteins
that both can be crystallized in the condition with PEG3350 and
Tacsimate
(although the concentrations are different) with different shapes. The
crystals look big and beautiful. However, when I test them in
synchrotron,
both of these two types of crystals showed poor diffractions. As
showed in
the attached diffraction image, the diffraction is up to ~4 A but
smear in
one direction while<8 A in the other direction. The interesting thing
is
that the diffraction pattern is similar for all crystals (from two
different
proteins) that I tested without exception although they belong to
different
space groups. So, I wonder whether these kind of pattern is caused by
Tacsimate (I don't know what it is) and how to rescue these crystals.
Any
suggestions or comments?
Thanks a lot!
Best,
Zhiyi
--
Matthew Bowler
Structural Biology Group
European Synchrotron Radiation Facility
B.P. 220, 6 rue Jules Horowitz
F-38043 GRENOBLE CEDEX
FRANCE
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Tel: +33 (0) 4.76.88.29.28
Fax: +33 (0) 4.76.88.29.04
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