library screening

Steven Russell Genetics sr120 at
Fri Nov 26 12:13:09 EST 1993

> In article <9311251954.AA09492 at> , suisheng at writes:
> > I have a question about a cDNA library screen. I don't know why there
> > are a few big round(2-4 mm diameter) clear plaques among those normal
> > size plaques in the plates.

If the library is really valuable it is possible to try and streak out E.coli 
from the middle of the offending plaques and thus isolate a strain resistant 
to the contaminating phage.  Then titre your library on several different 
single colony isolates and use the one which gives you the highest titre. I
have done this and it seems to be ok.

Steve Russell
Dept of Genetics
University of Cambridge

SR120 at 

More information about the Methods mailing list