Transcript Genetic Recombination in Bacteria

Bacteria Genetics
Introduction
Chromosome (bacteria are haploid; in other
words, they have a single chromosome)
 Mutations (change in the base sequence of
DNA)
 Extrachromosomal genetic material
Plasmid
Transposons
 Genetic recombination : Transfer of DNA
from one bacterium to another

Introduction

Changes in the genome can occur by two
processes
 Mutations
 Genetic

recombination
The changes in the genome is of
considerable importance in terms of
bacterial virulence and drug resistance
Genetic Recombination
The transfer of DNA from one organism to
another with subsequent integration into the
DNA of the recipient
Genetic Recombination
 Three
mechanisms
 Transformation
 Transduction
 Conjugation
Transformation
Definition

Genetic recombination in which a DNA
fragment from a dead degraded bacterium
enter a competent recipient bacterium and is
exchanged for a piece of DNA of the recipient
Mechanism
Dead/donor bacterium – source of DNA
 DNA fragment from the dead donor
bacterium binds to DNA binding protein on
the cell wall of the competent living recipient
bacterium

Transformation
Transduction
Definitions


Transduction - Genetic recombination in which a
DNA fragment is transferred from one bacterium to
another by a bacteriophage
Bacteriophage - A virus that only infects bacteria
horiz gene transfer-, Transposons--robert
Transduction
Conjugation

Genetic recombination in which there is a
transfer of DNA from a living donor
bacterium to a recipient bacterium, often
thorugh a sex pilus.

Pilus - A tubular protein structure
extending from a bacterial surface used for
attachment to environmental surfaces or
cells. A sex pilus is involved in bacterial
conjugation.
Plasmid Conjugation
R Plasmid Conjugation