Promega magic lambda preps

[Martin Kennedy]

In article <23m0lh$3f6 at usenet.INS.CWRU.Edu>, jjc4 at po.CWRU.Edu (James J. Campanella) writes:
> 
> Dear netters,
> 
> we seem to be having some problems with Promega's Magic Lambda Prep
> kit to purify lambda DNA. We have consistently been getting degraded
> DNA, despite treatment of the preps with proteinase K. Has anyone else
> been having this problem? Have you solved it. Promega's technical
> assistance was not very helpful-- they simply suggested that our
> enzyme buffers had nucleases in them (that was not the case since we
> have been using those same buffers on other DNA preps w/o degradation).
> We would be grateful for any suggestions. Thanks.
> -- 
> Jim Campanella | Vila: This is stupid, Avon

Quite often the degraded DNA in lambda preps is from bacterial chromosomal DNA
released during lysis, precipitated in the PEG step, and not removed by DNase
treatment.  Maybe you should check to see if this is the problem.  Perhaps your
lambda preps are ok, but the DNA is obscured by host chromosomal DNA.

Cheers,

Martin

NNNN   NN  Martin A Kennedy (E-mail = mkennedy at chmeds.ac.nz)  ZZZZZZZ  
NN NN  NN       Cytogenetic and Molecular Oncology Unit          ZZZ
NN  NN NN           Christchurch School of Medicine            ZZZ
NN   NNNN              Christchurch, New Zealand              ZZZZZZZ
		Phone (64-3)364-0880  Fax (64-3)364-750