Re: [ccp4bb]: Disulfide bridge

[Laurence Pearl <laurence@icr.ac.uk>]

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You could have a metal bound into the disulphide - this has been done 
intentionally in the past by reacting disuphide-bonded protein with Hg1+ 
which opens the disulphide, gets oxidised to Hg2+ and remains bound 
between the two sulphurs. More prosaically it could be a iron, zinc or 
even nickel from a metal chelate column. If you put ? into the structure 
what would the S-?-S angle be ?

Laurence Pearl

On Wednesday, September 11, 2002, at 03:08 , <deh22@cornell.edu> wrote:

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>
> Dear all,
>
> Has anyone ever seen a disulfide bridge that looks something like this:
>
> Cys-S-?-S-Cys
>
> If I force the disulfide bridge, the geometry does not fit the density
> at all.  If I let the sulfurs fit into the density correctly, the
> geometry does not work for a disulfide, although there is very clear
> density between the sulfurs.
>
> Any suggestions?
>
> Thanks,
> Darrell Hurt
>
>

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   Laurence H. Pearl

   Section of Structural Biology, Institute of Cancer Research
   Chester Beatty Laboratories,  237 Fulham Road
   London SW3 6JB, UK

   Phone +44-207-970 6045 : Secretary +44-207-970 6046
   FAX   +44-207-970 6051 : E-Mail l.pearl@icr.ac.uk
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