Bacterial conjugation - Conjugation between F+ and F- cell

Bacterial conjugation is the unidirectional transfer of genetic material from a donor cell to a recipient by cell to cell contact or through conjugation tube. The process is first described by Lederberg, Hayes and Woolman in E.coli.


Sex in Bacteria?
The bacterium with F plasmid is the donor, F+ve or male. Fertility factor genes confer bacteria with the ability to transfer genetic material to the recipient cell. The bacterium without F factor is the recipient or F-ve strain or recipient.  In E.coli, both these strains are present, one with F factor, F+ve or male and other without F plasmid, F-ve or female.
Remember, in bacterial conjugation, F plasmids are generally transferred, not the entire bacterial genome.
Case I: Conjugation between F+ and F- cell
Conjugation between F+ and F- cell
Conjugation between Fand F- cell
Step 1: F+ cells produces hair like appendenges called sex pili which facilitates cell to cell contact with F- strain by forming a conjugation tube. The formation of sex pili is governed by genes of F factor.
Step 2: Replication of F factor making a copy
Step 3: Transfer of copy of F plasmid to the recipient cell via conjugation tube.
Step 4: Conjugation tube dissolves
Now the F- strain is also F+. Remember, here bacterial genome is not involved.
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