Purification of cosmid DNA

[Mr. O.Coutelle NIMR]

In article <1994Nov18.182357.78048 at kuhub.cc.ukans.edu>, kannan at kuhub.cc.ukans.edu writes:
> I would like to know what's the best way to purify cosmid DNA.  the average 
> insert size in the cosmid library is about 40 kb.  i am interested in both 
> good quality DNA and high yield.  Could someone familiar with this give some
> suggestions.
> Is there any kit available.  Will th Wizard plasmid prep kit work for such 
> a ig size of DNA.
> 
> Thanks in advance.
> Kannan Thiru.  University of Kansas.

I have had extremely good results with the quiagen Midi-kit. From 250mls of o/n culture
I obtained about 40ug of DNA, which I used for dirtect cycle sequencing with the ABI
Taq terminator kit, and walking primers, which gave about 550bp of excellent sequence.
For quick digests, I found the wizard miniprep most convenient, but it  yields only
about 1-3ug from 3ml culture.