Do you have any Trp in your sequences?
We have found that on cleavage, Trp can pick up a CO2
(mw. 44) but upon standing in solution for a while
i.e. TFA buffers for HPLC, it goes away. It is also
stable enough at the outset that you'll get a second
significant peak on HPLC...which if you run it an hour
or two later, you should find that it's gone. The
same for Mass Spec.
Regards,
Steven Johnson
Research Associate, B.S.Chem
Process Development
Biomeasure, Inc.
--- mraida@gmx.de wrote:
> Hi all,
> we observe a number of peaks in MALDI-MS having a 44
> mass difference, but
> only up appr. MW 1400, the rest looks good and we
> could identify the
> protein. Other spots are also fine. Has anybody seen
> the same and knows what this
> is.
> Thanks a lot in advance
> Manfred Raida
> APB Proteomics
>
> --
> Dr. Manfred Raida
> European Proteomics Lab
> Amersham Pharmacia Biotech
> Munzingerstrasse 9
> D-79111 Freiburg
> Germany
> Email: Manfred.Raida@eu.apbiotech.com
>
__________________________________________________
Do You Yahoo!?
Send instant messages & get email alerts with Yahoo! Messenger.
http://im.yahoo.com/
This archive was generated by hypermail 2b29 : Mon Jun 12 2000 - 13:09:41 EDT