In article <306tcc$9ah at netnews.upenn.edu>, ljohnson at udcemail.udc.upenn.edu (Lois C. Johnson) writes:
> martin et.al.
> Just read you notice on miniprep dna and sequencing. Thanks!! I
> just had one question. Do you save the snotty part or not? ARe you adding
> the isoprop &/or NH4Ac & isoprop to the snotty part or the remainder in
> the tube if there is any!!??
> It may be obvious but of course I didn't get it!!
>> Thanks a bunch
The snotty stuff is pelleted, lysed cells and chromosomal DNA all gunked
together; i.e. it is garbage - but if you can think of a use for it, maybe we
can make some money out of it!!! The plasmids, because they are much smaller
molecules than the chromosomal DNA, sneak out into the supernatant as the
cells are lysing, so it is the supernatant you keep. You can either tip that
off into another tube into which you've already added isoprop, or just pick
out the gunk with a toothpick. I changed from the latter method to the
former, cos I think it gives slightly cleaner preps, but the latter method
uses only one tube per prep. Oh, and don't bother adding any more salt -
there is enough in the STET, and enough RNA to cause all the nucleic acid to
crash out. Don't freeze the isoprop/DNA mix either, as this is likely to
cause more crud to crash out - just spin immediately.
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)364-0750