What is the F factor in biology?

The donor bacterium carries a DNA sequence called the fertility factor, or F-factor. The F-factor allows the donor to produce a thin, tubelike structure called a pilus, which the donor uses to contact the recipient.

What is F plasmid write four points about it?

The fertility factor (first named F by one of its discoverers Esther Lederberg; also called the sex factor in E. coli or the F sex factor; also called F-plasmid) allows genes to be transferred from one bacterium carrying the factor to another bacterium lacking the factor by conjugation.

Where is the F factor in bacteria?

The F factor encodes genes for sexual pili, thin rod-like structures with which F-carrying (male or donor) bacteria attach to F− (female or recipient) cells for conjugative transfer. The F factor carries an operon of about 30 genes, encoding Tra proteins promoting transfer (Figure 1).

What is F+ and F?

F+ Cells = Cells containing F plasmid (F plasmid = Plasmid containing F factor) These are the bacterial cells which contains the F plasmid. They are called so, simply because they have F plasmid. We know plasmid is an extrachromosomal DNA that can replicate independently.

What is F+ F and Hfr?

The key difference between F+ strains and Hfr is that F+ strains have F plasmids in the cytoplasm freely without integrating into bacterial chromosomes while Hfr strains have F plasmids integrated to their chromosomes.

What enzyme nicks the F factor at oriT?

A relaxase, usually encoded by the plasmid, recognizes oriT, makes a single-strand DNA break (a nick) in oriT, and covalently attaches to the 5′ end of the nicked DNA strand via a phosphotyrosyl linkage (9, 34).

What is F factor in chemistry?

Definition. A DNA sequence or plasmid that confers certain bacteria the ability to produce a sex pilus for conjugation with other bacteria.

What is F cell in bacteria?

Bacteria in which contains F-factor and a part of chromosomal DNA integrated in it is known as F-prime bacteria. F’ cells are formed from Hfr cell during induction of F- factor from chromosomal DNA in which F-factor carries a portion of chromosomal DNA along with it.

What is f prime in genetics?

Definition. noun, plural: F’ bacteria. The bacterium possessing a plasmid containing the F factor and a part of the bacterial genome. Supplement.

Can f be a donor?

When the F factor is integrated into the bacterial chromosome, it can still act as the donor in a conjugation cross. These integrated strains are called Hfr, because of the high frequency of recombination that occurs when mated with F- bacteria.

How do F bacteria become F+?

There are some special terms to describe the state of F in a cell: F– refers to a strain without any form of F, whereas F+ refers to a strain with an F plasmid. F is very efficient at transferring itself from an F+ cell to an F– cell. After culturing F+ and F– cells together about 1/10 of the F– cells will become F+.

What does F+ mean in biology?

Fertility factor
We know plasmid is an extrachromosomal DNA that can replicate independently. It is called F plasmid because it has F factor which is Fertility factor. This fertility factor contains the genes require for the transfer or conjugation. F+ Cells = Cells containing F plasmid (F plasmid = Plasmid containing F factor)