Amp-r plasmids with defective lacZ gene

[Basavaraju Shankarappa]

> dear netters
> I wonder whether there is anyone aroung that has a mutated ampicillin
> resistance gene with internal tga stop codons? Any hints or helps
> would be appreciated because then I would not have to carry out
> site-directed mutagenesis myself.
> thanks in advance
> Josephine Stiebler
> Institute of Biochemistry
> University of Munich
> Am Klopferspitz 18a
> 8033 Martinsried

Hi Josephine:
	Check the pAlter vector and the mutagenesis system from Promega.
This vector has a defective amp-r gene which can be corrected for and
used along with the introduction of other oligo-mediated site directed
mutagenesis.  Hope you are not very particular about the kind of mutation
that is present in the lacZ gene because although I assume the mutation
in pAlter is the stop codon, I am not sure.
Hope it helps.
Raj Shankarappa
bsh at med.pitt.edu
Univ of Pittsburgh