Hi Ho--
We have had lots of success using the Hampton Research Crystal Screens 1 &
2 as additives. Sometimes these improve the crystal quality whereas the
96 Additive Screen does not. Whenever I screen for additives, I include
Crystal Screen 1 & 2. What I have NOT had a great deal of success with is
determining which component of the Crystal Screen reagent is responsible
for improving the crystal quality. Does not appear that it is just one
component in many cases.
I generally use 5% of the sparse matrix screen added to the well. When I
get a hit, then I further optimize the concentration of the reagent to add
to the well.
HTH!
annie
Annie Hassell
Glaxo Smithkline
5 Moore Drive
RTP, NC 27709
919/483-3228
919/483-0368 (FAX)
annie.m.hass...@gsk.com
"Ho-Leung Ng" <hole...@berkeley.edu>
Sent by: holeung...@gmail.com
20-May-2009 18:39
To
"CCP4 bulletin board" <CCP4BB@jiscmail.ac.uk>, annie.m.hass...@gsk.com
cc
Subject
Re: How to improve crystal which is twinning?
Hello Annie,
How effective have you found using sparse matrix screens as
additives vs. traditional additive screens? I've tried this only a few
times without success and would like to hear from someone with more
experience.
Thanks!
Ho
UC Berkeley
------------------------------------------------------------------------------
Date: Mon, 18 May 2009 09:34:12 -0400
From: Annie Hassell <annie.m.hass...@gsk.com>
Subject: Re: How to improve crystal which is twinning?
Heng--
Two things you might want to try:
1. Drop ratios with your current conditions and DMSO additive. Use=20
different concentrations of DMSO too.=20
2. Try using Hampton Crystal Screen and Crystal Screen 2 as additives. I
=
generally do this by adding 5% of XS 1 & 2 to the wells. Once I find
one=20
of these reagents that improves crystal quality/diffraction, I
optimize=20
the concentration for that. You can do this with the Mosquito robot
for=20
96 well format....or in the 24 well VDX trays.=20
Hope this helps!
annie
Annie Hassell
Glaxo Smithkline
5 Moore Drive
RTP, NC 27709
919/483-3228
919/483-0368 (FAX)
annie.m.hass...@gsk.com
