Insert instability

Jim Gale jim at AUDREY.LMF.ORG
Wed Mar 24 15:19:34 EST 1993

Greetings net-folks

I have two questions. First, I have a cDNA clone in pBluescript II which is 
unstable. That is when I grow this clone up from the glycerol stock, 
the majority of plasmid DNA I isolate has lost the insert. These Ecoli cells]
are rec-  but the insert is still being lost (deleted, recombined etc...)
I have re-transfected this plasmid into Stratagenes' SURE cells, which
are deletion mutants for a whole host of Ecoli evils, but the plasmid insert
is still not stable. For all you cloners out there, what tricks have you used
when you find your insert is not stable????

My second question is does anyone know of a vendor for homoginizing 
pestles that fit 1.5 eppendorff tubes. I saw a sample of these at a meeting
but I have lost the name of the supplier


Jim Gale
Lovelace Medical foundation
Albuquerque, NM
jim at

More information about the Methods mailing list