🦠microbiology review

F plasmids

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

F plasmids are extrachromosomal DNA elements in bacteria that facilitate the transfer of genetic material through conjugation. They play a crucial role in horizontal gene transfer and antibiotic resistance.

5 Must Know Facts For Your Next Test

  1. F plasmids contain genes necessary for the formation of a pilus, which connects donor and recipient cells during conjugation.
  2. They can integrate into the host bacterial chromosome, forming an Hfr cell that transfers chromosomal genes more frequently.
  3. F plasmids carry antibiotic resistance genes, making them significant in the spread of resistant bacterial strains.
  4. During conjugation, a single strand of the F plasmid DNA is transferred from the donor to the recipient cell, where it is then replicated.
  5. The presence of an F plasmid converts a bacterium into a donor (F+), capable of transferring genetic material to an F- (recipient) bacterium.

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