Annealing of two complementary circular SS DNAs

[Ned Mantei]

In article <DwFoKI.Lxw at cf.ac.uk>, Joe Boutell <boutell at cf.ac.uk> wrote:

All i had done with the colony preps after heating was pop them in 
> an ice bucket, so i think it is just a case of heating up and cooling 
> down, and they will anneal.

However, you were starting with closed-circular and double-stranded DNA,
so the strands were "pre-wound", so to speak. The original question
appeared to imply that the two closed circular *single* strands would be
present. These can't wind up completely as mentioned before, unless at
least one strand has a break.

-- 
Ned Mantei
Dept. of Neurobiology, Swiss Federal Institute of Technology
CH-8093 Zurich, Switzerland
mantei at neuro.biol.ethz.ch   Fax: +41-1-633-1046