Re: [ccp4bb] heavy atom derivative choice

- Protein crystallography

Main steps:

- Protein purification
- Crystallisation

Special:

- Programs for crystallography
- X-ray detectors

Basic tutorials:

   - Chemistry
   - Protein
   - Peptide
   - Amino Acids

Xtal community:

- CCP4BB

CCP4bb navigation

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

Previous message:
Subject: Re: heavy atom derivative choice
From: Miguel Ortiz Lombardia miguel {- dot -} ortiz-lombardia {- at -} AFMB {- dot -} UNIV-MRS {- dot -} FR
Date: 2009-07-15

Next message:
Subject: Re: heavy atom derivative choice
From: Savvas Savvides savvas {- dot -} savvides {- at -} UGENT {- dot -} BE
Date: 2009-07-15

Subject: Re: heavy atom derivative choice
From: David Briggs drdavidcbriggs {- at -} GMAIL {- dot -} COM
Date: 2009-07-15

Hi Sebastiano,

Free Cys' are crying out for Mercury derivatives. Try 2-3 with varying
sizes of additional groups - HgCl2, K2HgI4, PCMB, from the "Magic
seven" would be a good place to start.

Watch out for problems with your low pH, though. Some salts will form
insoluble hydroxide salts at pH 8.8. (HgCl2 & K2HgI4 should be okay)

Bart Hazes used to have an excellent set of notes online about heavy
atom derivatisation - I can't seem to find the URL right now...

HTH,

David

2009/7/15 Sebastiano Pasqualato :
> Hi all,
> I've got crystals of a protein of ca 200 residues, with 2 free cysteines, 5
> histidines, 2 methionines.
> We have nice diffraction for the native crystals, that grow in 150 mM KSCN,
> 17% PEG 3350, bis tris propane pH 8.8.
> We are crystallising the SeMet derivative, but I'm not completely sure I
> will be able to have nice crystals by saturday, when we have tunable time at
> the ESRF.
> I was thinking of trying with some heavy atom soaks, but only have like 30
> crystals, so limited trials allowed!
> Which compound would you advice as more likely to work, and thus worth
> testing?
> Thanks in advance for the suggestions,
> ciao
> s
>
>
>
> --
> Sebastiano Pasqualato, PhD
> IFOM-IEO Campus
> Dipartimento di Oncologia Sperimentale
> Istituto Europeo di Oncologia
> via Adamello, 16
> 20139 - Milano
> Italy
>
> tel +39 02 9437 5094
>

--
============================
David C. Briggs PhD
Father & Crystallographer
http://drdavidcbriggs.googlepages.com/home
Skype: DocDCB
============================

CCP4bb navigation

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

Previous message:
Subject: Re: heavy atom derivative choice
From: Miguel Ortiz Lombardia miguel {- dot -} ortiz-lombardia {- at -} AFMB {- dot -} UNIV-MRS {- dot -} FR
Date: 2009-07-15

Next message:
Subject: Re: heavy atom derivative choice
From: Savvas Savvides savvas {- dot -} savvides {- at -} UGENT {- dot -} BE
Date: 2009-07-15