I was searching for a plasmid in bacteria isolated from mice feces.
Therefore I diluted feces and spread them on LB plates containing
Ampicillin. I got some colonies, but I didn`t get any amplification
product using whole bacteria in a PCR with primers for the Amp.-gene.
I tested the bacs on LB Amp. plates with Aztreonam discs, no growing
near discs, so only Gramneg. bacs....Are there any Gramn. bacs Amp.
resistent without a plasmid or are there other Genes making resistent
than the betaLactamase Gene from pBR322 or are there inhibitors of PCR
in Enterobacteriaceae or is a 10min 95C -step not sufficient to lyse the
bacs....
TIA,
Chris