Re: [ccp4bb] Halide soaking

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

Previous message:
Subject: Halide soaking
From: tat cheung cheng theifire {- at -} YAHOO {- dot -} COM {- dot -} HK
Date: 2009-03-31

Next message:
Subject: Re: Halide soaking
From: Ethan Merritt merritt {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2009-03-31

Subject: Re: Halide soaking
From: Jose Antonio Cuesta-Seijo jcuesta {- at -} UHNRES {- dot -} UTORONTO {- dot -} CA
Date: 2009-03-31

Hi!

Normally the cell parameters, etc change very very little. You'll
only know if the bromides got in at the synchrotron by looking at the
fluorescence spectrum and at the anomalous signal. Normally some will
make it in and some will be in ordered sites, then it becomes mostly
a question of data quality to detect it.
You could also try the equivalent iodide soak. Iodine has a decent
anomalous signal at the copper wavenght and thus the anomalous signal
can be detected at your home source and many times the structure can
be solved by SAD or SIRAS. I would also thing that conditions that
give ordered iodide sites are likely to result in ordered bromide
sites, although the ions are not identical.

Jose.

**************************************
Jose Antonio Cuesta-Seijo
Cancer Genomics and Proteomics
Ontario Cancer Institute, UHN
MaRS TMDT Room 4-902M
101 College Street
M5G 1L7 Toronto, ON, Canada
Phone: (416)581-7544
Fax: (416)581-7562
email: jcuesta@uhnres.utoronto.ca
**************************************

On Mar 31, 2009, at 12:19 PM, tat cheung cheng wrote:

> Hi all
>
> I am now trying to do bromide soaking, but i am not really sure
> does the bromide atom enter my crystal. So is there any signs that
> indicate the entry of bromide atom? e.g. does the space group, cell
> dimension change? or just nothing change, and the bromide atom just
> get in?
> Thanks very much.
>
> T.C. Cheng
>
>
> Yahoo!»´ä´£¨Ñºô¤W¦w¥þ§ð²¤¡A±Ð§A¦p¦ó¨¾½d¶Â«È! ½Ð«e©¹ http://
> hk.promo.yahoo.com/security/ ¤F¸Ñ§ó¦h!
>

CCP4bb navigation

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

Previous message:
Subject: Halide soaking
From: tat cheung cheng theifire {- at -} YAHOO {- dot -} COM {- dot -} HK
Date: 2009-03-31

Next message:
Subject: Re: Halide soaking
From: Ethan Merritt merritt {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2009-03-31