Darren Stauth stauth at
Thu Dec 8 15:27:09 EST 1994

We recently started making competent cells using DMSO and PEG3350 and we
were excited at its ease and efficiency.  We are using DH5-alpha cells and
transforming TA ligations.  However, we are now running into the problem of
cell lawns appearing on our transformation plates containing amp.  First
the transformants appear and then a few hours later the lawn becomes
visible.  We have tested the amp and the cells both are fine.  Is the
treating of the cells to make them competent somehow causing them to be
resistant to amp?  Has anybody experienced this problem?   Any suggestions

"Life's a journey, not a destination...", Aerosmith

Darren M. Stauth -- stauth at

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