The review cited below is a great source of ideas to help you get your
ligand in your crystals
Hassell, A et al
Acta Crystallogr D Biol Crystallogr. 2007 Jan;63(Pt 1):72-9.
Crystallization of protein-ligand complexes.
Hopefully it may help you!
Dave
On 11/12/2007, Schubert, Carsten [PRDUS] <[log in to unmask]> wrote:
> Simon,
>
> solubilize your ligand in DMSO so it is maximally concentrated, 100mM works fine. Add enough compound to achieve 2-3 fold excess to your protein, mix and set up. Make sure your final DMSO concentration is ~3%, otherwise chances are you might harm your protein. If you cannot achieve a high enough stock concentration of DMSO to be below the 3% threshold, dilute you protein in the storage buffer to ~1mg/ml. Add compound to 2-3 fold access, incubate and co-concentrate to the desired concentration. That way you avoid the DMSO shock.
>
> Alternatively you could incubate the concentrated protein with the compound solubilized in water for 24-48hr and hope it is soluble and potent enough to get taken up by the protein and then set up your trays.
>
> HTH
>
> Carsten
>
>
>
> > -----Original Message-----
> > From: CCP4 bulletin board [mailto:[log in to unmask]]On
> > Behalf Of Yue Li
> > Sent: Tuesday, December 11, 2007 11:55 AM
> > To: [log in to unmask]
> > Subject: [ccp4bb] insoluble ligand
> >
> >
> > Hi all,
> >
> > I have one ligand which is insoluble in water, and I would like to
> > co-crystallize it with my protein. Is there any other method
> > except for
> > dissolving it in DMSO ?
> >
> > Thanks
> >
> > Simon
> >
> >
>
--
============================
David C. Briggs PhD
Father & Crystallographer
http://personalpages.manchester.ac.uk/staff/David.C.Briggs/
AIM ID: dbassophile
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