Hfr conjugation and exconjugant detection

An Hfr chromosome fragment transferred during interrupted mating between an Hfr donor cell to an F  recipient cell can undergo homologous recombination with the recipient chromosome. Exconjugants are detected on selective growth media, such as the minimal medium shown here An Hfr chromosome fragment transferred during interrupted mating between an Hfr donor cell to an F  recipient cell can undergo homologous recombination with the recipient chromosome. Exconjugants are detected on selective growth media, such as the minimal medium shown here

Mix in conjugation culture. Hfr donor thr' IeU' str‘ F' recipient thr Iew str“ ' 7 \ R plasmid Conjugation and partial T strand transfer due to interrupted mating. _ F factor segment Crossover srtes chromosomal fragment Enzymatic degradation One kind of exconjugant cell: thr leu‘ str" ,r _ ~5- Minimal medium lus streptomycin Only thr‘ leu‘ strR exconjugants grow.