bluescript

[Animesh Ray]

Date: Tue, 17 May 94 18:07:37 -0500
From: Animesh Ray <ray at ar.biology.rochester.edu>
Subject: bluescript
To: pstaswick at crcvms.unl.edu
X-Mailer: LeeMail 2.0.2
Message-Id: <A9FEB86A at ar.biology.rochester.edu>

I have never done this but let me try one explanation: perhaps your probe was 
made from a vector with homology to the bluescript vector and there is a slight 
contamination of the vector DNA in the probe preparation, and perhaps in the 
primary screen the bluescript vector plus insert may excise at a certain 
frequency spontaneously thus building up its copy number in the lysed cells 
within the plaque. So you will see a strong signal in those plaques but the 
signal actually comes due to hybridization of the contaminating vector DNA in 
the probe to the amplified bluescript DNA in these rare plaques. So, why not try 
to purify the probe fragment extensively before labelling? Oh well, may be I am 
wrong.

--
Animesh Ray
Dept of Biology
University of Rochester
Rochester, NY 14627
ray at ar.biology.rochester.edu
anmr1 at bphvax.biophysics.rochester.edu
Phone:(716)275-8986
FAX:(716)275-2070