Dear Martin,
The original procedure with polyethylene glycol comes from:
Stura, E.A. (1998) Strategy 3: Reverse Screening. In "Crystallization of
Proteins: Techniques, Strategies and Tips. A laboratory manual" (Bergfors,
T., ed) International University Line. pp. 113-124.
If you follow the procedure described within you should not have problems
in getting crystals in 15 mins
unless there is a problem with your hen egg white lysozyme.
The method given on the Rigaku site proposes 25% (v/v) ethylene glycol
instead of polyethylene glycol (2K-10K).
This would slow down the crystallization rate. You are better off using
polyethylene glycol 4K and then
transfer the crystals for freezing into 15% polyethylene glycol 4K, 25%
(v/v) ethylene glycol, 1M NaCl, pH 4.5
as your cryo-solution. Why wait 2 days when you can do it in 1 hour?
Enrico.
On Mon, 21 Dec 2009 17:12:48 +0100, MARTYN SYMMONS
<[log in to unmask]> wrote:
> Dear All
> checking out the Lysozyme crystallization methods on the web I
> liked the Rigaku Instructions that I found:
> (http://www.rigaku.com/protein/crystallization.html)
>
> "...create a drop of 3ul lysozyme solution, and 3 ul of well solution,
> respectfully, for a total drop size of 6ul..."
>
> So perhaps sometimes I am just not respectful enough to deserve crystals
> ?
>
> good wishes to all
> regards,
> Martyn
> -----------------------
> Martyn Symmons
> MRC-MBU Cambridge UK
> 'Chan fhiosrach mur feòraich.'
> Gaelic proverb -
> Nothing asked, nothing learned.
--
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
LTMB, SIMOPRO, IBiTec-S, CEA Saclay, 91191 Gif-sur-Yvette
Cedex FRANCE http://www-dsv.cea.fr/en/ibitecs/82
http://www.chem.gla.ac.uk/protein/mirror/stura/index2.html
e-mail: [log in to unmask] Fax: 33 (0)1 69 08 90 71
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