Re: [ccp4bb] heavyatom soaking problem

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

Previous message:
Subject: Re: heavyatom soaking problem
From: Raji Edayathumangalam redayath {- at -} MAIL {- dot -} ROCKEFELLER {- dot -} EDU
Date: 2007-06-28

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Subject: Re: compiling problems ccp4-6.0.2 and gcc-4.1.2
From: Tim Grune tim {- dot -} grune {- at -} SYNCHROTRON {- dot -} VIC {- dot -} GOV {- dot -} AU
Date: 2007-06-28

Subject: Re: heavyatom soaking problem
From: Melanie Adams madams {- at -} SCRIPPS {- dot -} EDU
Date: 2007-06-28

Hi,

In addition to selenomet and various cocrystallization attempts, directed iodination of specific Tyr residues prior to crystallization may also be helpful.

Cheers,
Melanie

-----Original Message-----
From: CCP4 bulletin board on behalf of Priyank Maindola
Sent: Thu 6/28/2007 10:28 AM
To: CCP4BB@JISCMAIL.AC.UK
Subject: [ccp4bb] heavyatom soaking problem

Hello all,
I am struggling with getting the phases out for my protein. Heavyatom
database shows that only mercury and samarium have the binding motifs in it.

Sodium iodide soak is killing the crystal even as less as 0.2 Molar
concentration for 30sec.
With Potassium iodide crystal is okay upto 0.75M for 1 & a half min but the
incorporation is not at relevent sites.(Iodide signal is not distinct and
is weak)
Hg & Au salts precipitate it.
With Pt signal is weak.
Somewhere I read that high salt causes problems for heavy atom to bind to
protein.My protein needs high salt for stability (750mM NaCl)

Please help with some suggestion!!

CCP4bb navigation

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

Previous message:
Subject: Re: heavyatom soaking problem
From: Raji Edayathumangalam redayath {- at -} MAIL {- dot -} ROCKEFELLER {- dot -} EDU
Date: 2007-06-28

Next message:
Subject: Re: compiling problems ccp4-6.0.2 and gcc-4.1.2
From: Tim Grune tim {- dot -} grune {- at -} SYNCHROTRON {- dot -} VIC {- dot -} GOV {- dot -} AU
Date: 2007-06-28