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.
NNNN NN Martin A Kennedy (E-mail = mkennedy at chmeds.ac.nz) ZZZZZZZ
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