dam- e.coli

[Ashok Aiyar]

In article <9209171348.AA21614 at phobos.med.pitt.edu> bsh at MED.PITT.EDU (Basavaraju Shankarappa) writes:
>
>This question is for people who have worked with dam- E.coli.
>I was given a dam- strain called GM33.  When I attempted to make competent
>cells by the CaCl2 procedure, the cells would aggregate kind of precipitate
>the moment 100 mM CaCl2 solution is added.

We use a strain called GM161.  It seems to transform reasonably well with 
supercoiled DNA.  We do use a standard CaCl2 procedure.  With ligated DNA, 
you are better off transforming another strain and then moving supercoiled 
DNA back into the dam- strain.

Electroporation doesn't seem to work too well with this strain.

Ashok
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                             Ashok A. Aiyar
                       Department of Biochemistry
                         CWRU School of Medicine
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