Consider conjugation in Escherichia coli. In which of the following matings would chromosomal genes be transferred most frequently?
A) F⁺ × F⁻
B) F⁻ × F⁻
C) Hfr × F⁻
D) F⁺ ˣ F⁺

Question

Quizplus · Accepted Answer

In an Hfr × F⁻ mating, the Hfr (high-frequency recombination) strain (with the F plasmid integrated into the chromosome) will transfer chromosomal genes to the F⁻ recipient cell more frequently than in other matings. This is because the entire bacterial chromosome is replicated and transferred linearly into the F⁻ cell before the F plasmid. Therefore, genes located closest to the origin of replication will be transferred first, followed by genes farther away. However, the transfer of chromosomal genes in other matings (A, B, D) is limited by the presence of the F plasmid, which is not integrated into the chromosome and transfers independently.

Consider Conjugation in Escherichia Coli