Re: [ccp4bb]: questions on dimers in crystal packing

[Ricardo Aparicio <aparicio@if.sc.usp.br>]

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Actually, you can form different dimers depending on your crystallographic symmetry. To
decide which dimer is functional in solution is a different issue.
I have seen cases where Small-Angle X-ray Scattering (SAXS) was able to determine which
dimer was functional in solution, what was not clear from the crystal only.

Cheers,


Ricardo Aparicio
USP/Brazil


PS: A good site for SAXS is
http://www.embl-hamburg.de/ExternalInfo/Research/Sax/




Rongjin Guan wrote:
> Sorry this is not a ccp4 question.
> Can anybody give some hints on the following questions?
> 
>             1. Can one molecule form more than 1 kind of dimers
>                in different crystallization conditions?
> 
>             2. If the answer is "yes", is there any possibilities
>                that there is a dynamic equilibruim between them, and
>                what we see in the crystal structure is the main
>                dimeric form or the favorite dimer form?
> 
>             3. what are the main factors controling the dimer formation?
> 
>             4. Can the dimer formed in crystals reflect the situation in 
> body
>                 if it is known to function as dimers biologically?
>  
> 
>             any hints and clues will be greatly appreciated.
> 
>             Rongjin
> 
> -- 
> Rongjin Guan, Ph.D.
> Center for Advanced Research in Biotechnology
> 9600 Gudelsky Drive
> Rockville MD, 20850
> Tel: 301-738-6210
> Fax: 301-738-6255
> 
>