*** For details on how to be removed from this list visit the ***
*** CCP4 home page http://www.ccp4.ac.uk ***
Of course MS is possible (plenty of material is available from a
crystal) but may not give you the answer - fingerprinting might miss the
region in question, the entire (truncated) beta chain may not fly
(especially when it comes from an SDS gel; of course you can try washing
and dissolving the x-tals without going via SDS PAGE).
Definite answer: SDS gel - blot - N-terminally sequence the (truncated)
beta chain.
Jinkwang wrote:
Hi all,
Routine MR solution of a mutant structure was an easy task until I
found a clear cleavage within the polypeptide chain. This cleavage is
reproducible only in crystal structure, and biochemical studies such
as SDS-PAGE, N-terminal sequencing or Mass spectra never indicate any
cleavage in the chain.
The protein has about 700 amino acids, divided into alpha (200 a.a)
and beta (500) chains. The cleavage is found at 28-29 of the beta
chain in the crystal. Wondering whether this could occur only in
crystal states, the crystals were dissolved, but the biochemical
studies did not show any cleavage, but crystal structure once again shows.
Any comments are highly appreciated.
Regards,
Jin Kwang
--
PD Markus Wahl, Ph.D.
Max-Planck-Institut fuer Biophysikalische Chemie
Abteilung Zellulaere Biochemie/Roentgenkristallographie
Am Fassberg 11
D-37077 Goettingen
Germany
Phone: +49 (0)551-201-1046
Fax: +49 (0)551-201-1197
eMail: [EMAIL PROTECTED]
Homepage: http://www.mpibpc.mpg.de/groups/wahl
