The F plasmid is a circular DNA molecule around 100 kilobase pairs that contains genes allowing it to transfer chromosomal genes from an F plasmid-containing cell to one that does not. It contains an IS element that acts as a transposable element and helps the plasmid move. The F plasmid contains an origin of transfer (oriT) that initiates transfer within a cis-acting site, as well as an origin of replication (oriV) that allows the plasmid to reproduce. It also contains a tra region with pilin and regulatory genes that form pili on the surface of F bacteria to initiate conjugation. The F plasmid is able to self-transfer through these pili and replicate independently or integrate into the bacterial chromosome

1. F Plasmid
Dr. P. Suganya
Asssitant Professor
Departemnt of Biotechnology
Sri Kaliswari College ((Autonomous), Sivakasi

2. The F plasmid Is a double – stranded circular DNA molecules of
about 100 kpb.
F = Fertility Factor Or Sex Plasmid
Its Ability to transfer chromosomal genes from a cell containing F
Plasmid to one that does not.
INTRODUCTION:

4. IS ELEMENT:
• Is an insertion sequence element or IS element.
• Is act as a simple transposable element.
• Is help to moment with the help of transposase enzyme.
Tn 1000 :
Is Transposed to several site.
This leads to the appearance of donors transferring their
chromosome from several fixed point oriT and in opposite directions.
The location of these point and the direction of transfer are
determined by Tn 1000 insertion site and their orientation.

5. Ori T :
 Origin of transfer (ori T)
 On transmissible plasmid DNA transfer initiate with in a cis actin
Site , the origin of conjugal transfer
 Is a nucleotide sequence (~40 - ~500 bp length )
Ori V :
 The replicon is comprised of the origin of replication (ori) and all Of its
control elements.
 The ori is the place where DNA replication begins, enabling a plasmid to
Reproduce itself as it must to survive within cells

6. Tra region :
 The Tra locus include the pilin gene and regulatory genes,
which together form pili on the cell surface of F – bacteria
and initiate the conjugation.
 The existence of the tra region of a plasmid genome was
first discovery in 197 by David H

8. Mechanisms:
1. F+ Bacterial Cell have surface appendage called F – pili or sex sex. Which are coded by the F Plasmid. An
F= Cell has 23 pili. They are hair like structure about 2-3um length and appear as extension from the bacterial
Cell wall. A single subunit protein ‘Pili’ coded by genes Tra A polymerizes into ‘Pilus’.
2. The sex pili unnecessary contact to the donor and recipient cell
3. When the tip of the F pilus contact the surface of recipient (F-) cells, mating is initiated.
4. Its has ability to self transmissible

9. 5. Number of copies / chromosome is 1 to 2 per cell
6. F+ is a Donor Cell and The F- is a recipient cell
7. F+ donor cell is transfer plasmid into F- recipient cell
8. F plasmid can replicate independently or can integrate into the chromosome, it is considered an episome.
The capacity of f plasmid to integrate at different location and in either orientation on the chromosome allowed
The determination. For some time F was the only known conjugative plasmid.

10. Thank You