Dear Klaus, Using 250-500 miL of AL's oil ( 1:1 mixture of paraffin and silicone oil) to cover your well solution (in case u are using vapor diffusion) or even ~10 miL of oil on top of your drop can help to reduce nucleation rate and provide single crystals of higher diffraction quality.
My two cents, cheers! Arka Chakraborty On Wed, Jan 22, 2014 at 4:57 PM, Enrico Stura <[email protected]> wrote: > 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 > LTMB, SIMOPRO, IBiTec-S, CE Saclay, 91191 Gif-sur-Yvette, FRANCE > 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 > -- *Arka Chakraborty* *ibmb (Institut de Biologia Molecular de Barcelona)* *BARCELONA, SPAIN*
