From: JCaplan339@aol.com
Date: Mon, 20 Jan 1997 19:05:01 -0500 (EST)
Subject: Unknown peak during Prot. Seq.
To: Recipients of ABRF List <abrf@aecom.yu.edu>
Hello to the ABRF world,
I am a first time participant in this discussion group. Many thanks to Ruth
and Audree for their prompt answer to my eMail sent on 1/13/97 (received
answers on 1/14/97).
I have an unknown peak that elutes approx. 0.2 min after PTH-Glu and just
before DMPTU. The peak is the predominant peak and is the first residue in
the sequence of a native OMP. We are using a ABI 477A with A3/Premix and B2
buffer system.
Our initial thought was a derivative (of some sort) of cysteine, however, no
chemical modifications (alkylations) have been done to the protein. We were
thinking of the derivative formed by acrylamide, however, the same peak
appears from sequencing a direct polybrene treated glass filter spot as from
sequencing the PVDF band from an SDS-PAGE transfer (the protein has not come
into contact with acrylamide).
Any suggestions?
Thank you,
Jeff
The accompanying eMail address is my home eMail address. My work eMail
address is Jeffrey_Caplan@Internetmail.PR.Cyanamid.com.