Catenanes (was Re: Gentle Plasmid prep protocol needed)

Peter Wang plw at
Wed Jul 15 09:26:30 EST 1998

Frank O. Fackelmayer wrote:
> ... The longer the
> incubation time, to more catenanes (interconnected supercoiled circles) you
> get, especially with very high copy number plasmids like bluescript. If you
> want to have a very high proportion of only formI-DNA, grow for the shortest
> time possible. Do not use overnight cultures, but inoculate you culture in the
> morning and let it grow to OD=1 (1.5maximum).....

That's interesting, I didn't know that there was significant catenane
production in vivo; shouldn't gyrase disconnect these?  Do you have any
more information or a reference on this phenomenon?  Thanks.

- Peter
Peter Wang, M.D., Ph.D.
MRC Centre for Protein Engineering,
Hills Road, Cambridge, CB2 2QH, England

Tel (01223) 402104  (international calls +44-1223-402104)
Fax (01223) 402140  (     "          "   +44-1223-402140)

More information about the Methods mailing list