Rather difficult to decide. It depends on whether BME was present during
all protein purification steps. Also, BME is somewhat short lived. You
have to add new BME every few days or so. At least one looks like it
could be oxidized, a process that cannot be reversed by BME....
J.
Artem Evdokimov wrote:
>
> Hi,
>
> They’re likely both BME adducts, just in the first case the CH2CH2OH
> portion is way more disordered.
>
> Artem
>
> ------------------------------------------------------------------------
>
> *From:* CCP4 bulletin board [mailto:[log in to unmask]] *On Behalf
> Of *[log in to unmask]
> *Sent:* Monday, August 13, 2007 9:59 PM
> *To:* [log in to unmask]
> *Subject:* [ccp4bb] extra density on Cysteine
>
>
> 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
>
--
Jeroen Raymundus Mesters, Ph.D.
Institut fuer Biochemie, Universitaet zu Luebeck
Zentrum fuer Medizinische Struktur und Zellbiologie
Ratzeburger Allee 160, D-23538 Luebeck
Tel: +49-451-5004070, Fax: +49-451-5004068
E-mail: [log in to unmask]
Http://www.biochem.uni-luebeck.de
Http://www.iobcr.org
Http://www.opticryst.org
--
If you can look into the seeds of time and say
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