Re: [ccp4bb] How to dissolve a hydrophobic peptide?

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: refmac5
From: sajid akthar b_sajid_ali {- at -} YAHOO {- dot -} CO {- dot -} IN
Date: 2008-04-16

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Subject: Re: How to dissolve a hydrophobic peptide?
From: David Briggs drdavidcbriggs {- at -} GMAIL {- dot -} COM
Date: 2008-04-17

Subject: Re: How to dissolve a hydrophobic peptide?
From: Chavas Leo ccp4hnaalas {- at -} GMAIL {- dot -} COM
Date: 2008-04-16

Dear Jiamu Du --

> I want to crystallize a mAb Fab in complex with a hydrophobic
> cyclic peptide. The peptide contains 1 hydrophilic residue, 2 Cys,
> and 9 hydrophobic residues. The problem is that I can not dissolve
> this peptide in common buffers. I think it is need to dissolve it
> in some organic solvent, such as DMSO. But organic solvent is
> harmful to protein.
> Is there any sugestions for this situation?

This has been addressed before. If I recall quote the previous answer
properly:
" In the case of insoluble ligands, solubilize the ligand in DMSO so
it is maximally concentrated, 100mM works fine. Add enough compound
to achieve 2-3 fold excess to the protein, mix and set up. Make sure
the final DMSO concentration is ~3%, otherwise chances are it harms
the protein. If one cannot achieve a high enough stock concentration
of DMSO to be below the 3% threshold, dilute the 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 it avoids
the DMSO shock. Alternatively one 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 the trays."

Please note here I'm only referring to a previous e-mail from the bb.
Never tried it myself.

HTH

Kind regards.

Leo
------------------------------------------------------------
Chavas Leonard, Ph.D.
Research Associate
------------------------------------------------------------
Faculty of Life Sciences
The University of Manchester
The Michael Smith Building
Oxford Road
Manchester Lancashire
M13 9PT
------------------------------------------------------------
Tel: +44(0)161-275-1586
e-mail: Leonard.Chavas@manchester.ac.uk

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: refmac5
From: sajid akthar b_sajid_ali {- at -} YAHOO {- dot -} CO {- dot -} IN
Date: 2008-04-16

Next message:
Subject: Re: How to dissolve a hydrophobic peptide?
From: David Briggs drdavidcbriggs {- at -} GMAIL {- dot -} COM
Date: 2008-04-17