Klaus,
You say "that crystallises readily"
So you have solved your own problem. You need to control the rate at which
the crystals grow.
Among all the things you have tried already, you may have the answer
regarding how you can
control the crystal growth rate so as to slow it down enough as to have
large single crystals that
are not intertwinned. This is achievable unless your sample has impurities
or aggregates.
Enrico.
On Wed, 22 Jan 2014 16:01:44 +0100, Klaus Fütterer <[email protected]>
wrote:
Dear ccp4bb contributors,
We are dealing with the problem of a protein (~ 50 kDa) that
crystallises readily, but has an annoying habit of forming highly
intergrown rods or needles.
Even when the crystals look optically homogenous under the microcsope,
diffraction is so so (3.5 Å or so on the synchrotron), but patterns
reflect several crystal lattices that the processing software cannot
resolve properly.
We have tried this:
- additive screens
- switching the His-tag from N- to C-terminus
- cutting the tag
- thermal stability screens in a variety of buffers
- growth in the presence of potential ligands/substrates
Any suggestions for tricks that we haven't thought of so far?
Thank you.
Klaus
=======================================================================
Dr. Klaus Fütterer
School of Biosciences P: +44-(0)-121-414 5895
University of Birmingham F: +44-(0)-121-414 5925
Edgbaston E: [email protected]
Birmingham, B15 2TT, UK W: http://tinyurl.com/futterer-lab
=======================================================================
--
Enrico A. Stura D.Phil. (Oxon) , Tel: 33 (0)1 69 08 4302 Office
Room 19, Bat.152, Tel: 33 (0)1 69 08 9449 Lab
http://www-dsv.cea.fr/ibitecs/simopro/ltmb/cristallogenese
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http://scholar.google.com/citations?hl=en&user=Kvm06WIoPAsC&pagesize=100&sortby=pubdate
http://www.chem.gla.ac.uk/protein/mirror/stura/index2.html
e-mail: [email protected] Fax: 33 (0)1 69 08 90 71
