I'm almost sure that there is a formation of an aspartimide in
Asp-Gly position. If you are synthesizing the peptide in a Fmoc mode,
you can solve this problem adding 0,1 M of HOBt in your deprotection
solution. (check Lauer et al, Letters in Peptide Science, I (1994),
197-205).
Janelle Lauer helped me greatly when i had this problem
before.
Leo
> Date: Wed, 25 Feb 1998 13:52:47 -0500
> From: Mary Bower <bower@biochem.purdue.edu>
> Subject: Peptide Synthesis
> To: Recipients of ABRF List <abrf@aecom.yu.edu>
> Hello everyone,
>
> I have synthesized a peptide with the sequence CDGSVWAQSESFPELK. The HPLC
> shows two major peaks adjacent to each other with the major peak being a
> dehydrated (-18) species of the peptide as shown by mass spec. I suspect
> pyroglu. formation, but I'm not sure where. Can anyone comment on what
> might have happened here and what I can do to prevent this if I need to
> resynthesize??
>
> Thanks in advance!
>
> Mary
>
> Mary Bower
> Instrument Specialist
> Purdue University
> Department of Biochemistry
> West Lafayette, IN 47907
>
> Phone (765)494-6540
> Fax (765)494-7897
> email; Bower@Biochem.purdue.edu
>
>
>
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Leo Kei Iwai - Chemist
Dept of Biophysics
Escola Paulista de Medicina - EPM - UNIFESP
Lab of Transplant Immunology
Instituto do Coracao - Incor - FMUSP
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