Plasmid F′128 was formed by an exchange between chromosomal Rep sequences that placed lac near dinB between many pairs of Rep sequences. Plasmid F′128 is critical for selection-enhanced lac reversion (adaptive mutation), which requires prior lac amplification. The structure of F′128 supports the idea that amplification is initiated by Rep-Rep recombination and that general mutagenesis requires coamplification of dinB (error-prone polymerase) with lac.
ASJC Scopus subject areas
- Applied Microbiology and Biotechnology