2cystein.jpeg looks just like oxidation of cysteine to
S-hydroxy-cysteine (a.k.a. cysteine sulfenic acid). I have seen this
repeatedly in one of my structures (E. coli aminopeptidase P, see 1WL9
for an example). We discuss this a bit in Graham et al (2005)
Biochemistry 44: 13820-36 - see Figure 2 and surrounding text.
Cheers,
Stephen
On 8/14/07, [log in to unmask] <[log in to unmask]> wrote:
>
> Dear all,
>
> I am refining a 2.0A structure. I found that there were some extra density
> on two cysteines, even though I have added 5mM BME in the protein buffer.
>
> I am wondering whether the first one (Cys292) is a bme and the second one is
> an oxidized cysteine. Any suggestion?
>
> I attached the images for your reference. thanks
>
> Regards
> _________________________________________
> Xu Ting ,Ph.D
> 10 Biopolis Road
> Singapore 138670
> Fax: +65 6722 2916
> Phone: +65 6722 2980
>
--
Dr Stephen Graham
Nuffield Medical Fellow
Division of Structural Biology
Wellcome Trust Centre for Human Genetics
Roosevelt Drive
Oxford OX3 7BN
United Kingdom
Phone: +44 1865 287 549
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