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Sexduction or F-duction - Conjugation between F’ cell and F- cell

Case III:  Sexduction or F-duction: Conjugation between F’ cell and F- cell
What is F cell?
F cell: The integration of F plasmid in the formation of Hfr strains is reversible process. At times, detached F factor contains one or more bacterial genes that were close to the integrated F factor. Such a cell is referred as F (F dash cell)
F cell has an independent detached F plasmid with some bacterial genes attached to it. Then plasmid is called F plasmid.

Sexduction: is the conjugation between F cell with F- recipients. Sexduction offers high rate of recombination. After conjugation, F- cell receive f plasmid along with few bacterial genes. Thus F- cell becomes diploid for few genes (partial diploids).


Sexduction
Sexduction or F- duction: Transfer of F factors to receipt occur in mating between F1 and F. The transfer of Fto receipient produce partial diploids or heterogenotes. Recombination may occur between the recipient’s chromosome and F1, producing recombinants. Recombination of this type, mediated by F1 factors, is called sexduction or F-duction. (Here a, b and c are representative genes)
Step 1: Formation of F cells or F plasmids
Step 1: F plasmid detaches from the parent chromosome. During this release, genes that are close to integrated F plasmid may attach to the detached F plasmid. Such a cell that has a detached F plasmid with some bacterial genes attached to it is referred as F’ cells
Step 2: F cells produces hair like appendages 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 3: Replication of F plasmid making a copy
Step 4: Transfer of copy of Fplasmid to the recipient cell via conjugation tube.
Step 5: Conjugation tube dissolves. Now F- cell is diploid for few bacterial genes (or partial diploid).
Step 6: The transferred F plasmid has some bacterial genes attached to it. This brings about genetic variability.
In short: Fcell + F- cell = F cell + F cell

To conclude, bacterial gene transfer is not like sexual reproduction in higher organisms. Only a few genes or F plasmid is transferred from donor bacterium to recipient bacterium in the process.
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