Question

What are the 4 forms of gene transfer in bacteria? What is the difference between horizontal and vertical gene transfer? What is gene transfer? How genes move between genomes of bacteria.by the processes of transformation, transduction, conjugation, and transposition? How can gene transfer (conjugation, transformation) contribute to bacteria becoming resistant to antibiotic drugs?

Answer 1

Answer :

1) Following are the four forms of gene transfer in bacteria

A) Transformation - When a free DNA from environment usually a dead bacterium enters a living bacterium and gets incorporated, the process is called transformation .

B) Transduction - Transfer of genetic material with the help of bacteriophage from one bacterium to other is called transduction

C) Conjugation- Transfer of DNA usually a circular DNA called plasmid from one bacterium to other through contact is called conjugation

D) Transposition- Transfer of a segment of DNA from one site to other site.This mobile segment of DNA is called transposon or jumping gene and the process is called transposition .

2) Horizontal gene transfer - Transfer of gene from donor bacterium to recepient bacterium which is not a progeny of the donor bacterium. Vertical gene transfer - Transfer of gene from donor bacterium to recepient bacterium which is progeny of the donor bacterium.

3) Gene transfer is the transfer of genetic material from one organism to other by different modes .

In transformation gene from environment usually a dead bacterium is acquired by a living bacterium .

In transduction , movement of gene occurs with the help of bacteriophage .

Conjugation - Movement of genes by direct contact of two bacteria with the help of structure known as pilus .

Transposition - Transfer of jumping genes from one place to another in the genetic material .

4) Suppose there are 2 bacteria A and B. A contains genes which confers resistance to penicillin but B lacks that gene and thus B is sensitive to penicillin .

If by the process of gene transfer bacterium A transfers gene encoding for penicillin resistance to bacterium B.

Hence, the bacterium B which was originally sensitive to penicillin becomes resistant to penicillin due to gene transfer .