Message-Id: <v01540b22af0d2a72492b@[207.41.61.83]>
Date: Thu, 23 Jan 1997 10:11:59 -0500
From: jcrabb@northnet.org (John W Crabb)
Subject: Re: keratin
To: Recipients of ABRF List <abrf@aecom.yu.edu>
Steve
Many of us see human keratin sequences from time to time, particularly from
electrophoretically purified samples. My best guess is that it comes from
dandruff and probably introduced into one or more of the electrophoresis
reagents during manufacturing and/or packaging. Who knows where it really
came from but obviously it can't be introduced by either the "customer' or
the sequencing facility. Try not to waste too much time arguing about
it-suggest that the investigator change his reagent supplier and go on with
life.
John W Crabb
>I just seqenced a couple of peptides from a tryptic digest of a PVDF blot. The
>sequences the "customer" wanted were at about the 10-15 pmole level. In one of
>the peptides a second sequence starting at about the 3 pmole level was easily
>read out to twelve amino acids. This second sequence turned out to be a
>tryptic peptide from keratin. So my question is where did it come from, skin?
>As I told the customer "I wore gloves".
>I recall seeing this a couple of years ago and chalked it up to someone's poor
>technique and forgot about it.
>I wonder how often this happens?
>Has any one sniped off a chunk of skin and processed it for internal
>sequencing?
>
>Steve