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transformation - Possible to get two diff. plasmids? (Aug/14/2004 )

Hi peeps,

Is it possible for heat-shocked-transformed E.Coli cells to take up two different plasmids from a ligation reaction?

I did miniprep of uncut plasmid from a colony and initial data (sizes of supercoiled DNA) seem to indicate that they've taken up a circular vector and a circular vector+insert.


Yes, that can happen.

It's (even) less likely than the takeup of one plasmid (transformation is a very ineffective process - but we beat the statistics with billions of bugs and copys of plasmids), but it can happen and will happen sometimes.

So, just bad luck.

But you can always take the mini prep of your mixed plasmids and transform that again - you should get about a 50/50 ratio of "goods" and "bads" .