Message-Id: <9701232231.AA0991@pho903.sbphrd.com>
From: Jacek Mozdzanowski-1
Date: 23 Jan 97 12:00:03 EDT
Subject: keratin
To: Recipients of ABRF List <abrf@aecom.yu.edu>
One of the most common sources of keratin(?) contamination is buffer B (1M
tris, pH 6.7) used for the preparation of stacking gel of the standard
tris/glycine polyacrylamide gels. We routinely keep the buffer refrigerated
for no longer then 4 weeks - then discard it and prepare fresh. Our buffer B
contains 0.05% azide. If the buffer goes wrong then there is a double band
across the gel visible after silver staing of the gel or colloidal gold
(AuroDye) staining of the membrane. Seeing the same band after CB staining (or
amido black on the membrane) indicates severe contamination, usually not _only_
buffer B related. The molecular weight suggests keratin, but I have never
attempted to identify it by sequencing. Has anybody?
Jacek Mozdzanowski
Analytical Sciences
SmithKline Beecham