Re: Peptide Synthesis

Haaseth@brcf.med.umich.edu
Wed, 25 Feb 98 17:01:48 EST

Mary, you have Asp-Gly problems! You will probably need to
resynthesize the peptide. When you incorporate your Asp, you
need to have HOBt or p-nitrophenol in the piperidine to reduce
aspartimide formation. We use 0.1 M HOBt in the pip and get
much improved results. The famous Greg and Cynthia Fields paper
is cited here, if I had the reference handy. This problem usually
elicts several responses from this list, so more and more
detailed information will probably be on the way.

Ron Haaseth
U of Mich
verdin@umich.edu

______________________________ Reply Separator _________________________________
Subject: Peptide Synthesis
Author: Mary Bower <bower@biochem.purdue.edu> at Internet
Date: 2/25/98 3:01 PM

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