Plasmid DNA Extraction

[Lixin Zhou]

In article <92364.221112U09723 at uicvm.uic.edu>, Lixin Zhou <U09723 at uicvm.uic.edu>
says:
>
>I got troubles in extracting plasmid DNA from Streptococcus
>pneumoniae (Gram-positive).  The plasmid is about 15 kb.
>Pneumococcal chromosomal DNA and plasmid DNA are AT rich (about
>62%).  The method I used is a modified alkali lysis protocol.
>Solution II contains 1% SDS and 0.175 N NaOH instead of 0.2 N NaOH.
>Solution III contains 50 mM Tris.Cl-pH8.0 in addition to 0.1 M
>NaAc-pH4.8.
> ....

I have found a mistake in the modified protocol.  0.1 M NaAc-pH4.8
in Solution III should be 3 M.  I misunderstood the modified protocol
which was not mine.

I appreciate the suggestions appearing in Bionet and delivered in my
personal mailbox.

With apologies,

Lixin Zhou
Laboratory for Molecular Biology, University of Illinois at Chicago