replication of plasmids

[Frank O. Fackelmayer]

Robert Whittier wrote:

> >Susanne Rohrer wrote:
> >>
> >>My question: can a plasmid containing 2 identical origins replicate,
> >
> >No, it can't.
> >
> >>i.e. could pUC be ligated with itself?
> >
> >Yes, it can, but the product will not replicate.
> >
> >-Rafa
>
> Whoa . . .
> not so fast there pardner!
>
> Plasmids transformed into recA+ strains naturally form dimers
> and trimers, and I have a vague recollection of some paper
> in the late 70's that showed you could isolate the monomer
> band or the dimer band. Transformed back into a recA- strain,
> each would replicate faithfully in whichever form (monomer or
> dimer) was used to transform. Transformed back into a recA+
> strain, the same spectrum of monomer, dimer, trimer, etc. forms
> would reappear.
>

could you try to dig out the reference? That sounds interesting and I
would like to see the original data...

Frank