Bacterial transduction is the process by which bacteria can acquire genetic material from other bacteria through viruses. There are two main types: generalized transduction, where any bacterial DNA can be transferred during a lytic viral infection, and specialized transduction, where a specific region of bacterial DNA is incorporated into a temperate phage and transferred. Transduction was first discovered in 1952 by Lederberg and Zinder while studying Salmonella bacteria. It allows for genetic exchange between bacteria and influences bacterial evolution and adaptation over time.

1. Bacterial transduction
Dr.Sujit Ghosh

2. Survival and advancement of
microorganisms with time is fundamentally
influenced by the capacity of the
microorganisms to exchange hereditary
material without sexual reproduction.
Hereditary material can move, starting with
one cell then onto the next through a few
distinct mechanism, either as bare DNA ordistinct mechanism, either as bare DNA or
DNA encapsidated in an virus particle.
Oneway that microorganism procure that
vital DNA component for new qualities is by
the formation of lysogens of temperate(mild)
bacteriophage (e.g. Lambda Phage).

3. After infecting a host cell temperate phages settle on a decision for
choosing lysogenic or lytic. If lysis is chosen, those involved in DNA
replication and capsid production- lytic infection genes are expressed,
as in any normal lytic infection cycle. if there is critical accumulation of
a repressor for these lytic qualities, the phage DNA may integrate into
the host chromosome. Once a temperate phage has turned out to be
incorporated into the genome of the host cell, there will be a couple ofincorporated into the genome of the host cell, there will be a couple of
prophage qualities expressed in the host cell. The declaration of
prophage qualities can give the host cell new attributes, including
resistance to reinection by a similar phage, or toxin production. The
capacity of a prophage to give a host cell new attributes is called
phage transformation.

4. Types of
Bacteriophage
Virulent Temperat
e
Does not cause destrupticCapable of causing
infection and eventually
destruction and death of
the bacterial cell. These
follow the lytic cycle.
. T4 host E.coli.
Does not cause destruptic
infection instead phage DNA is
incorporated into bacterium
DNA and is replicated with it
and after some cycle become
virulent cause lysis.
lambda phage.

5. Discovered by :
•Transduction was first discovered in
1952 by Joshua Lederberg and
Norton Zinder
Studied system:
•Studied in Salmonella typhimurium
•Plated two auxotrophic strains (LA-2
and LA-22) individually on minimal
medium, no cells grew.
•Plated a mixture of the two
auxotrophic strains on minimal
medium, cells grew into colonies.
•Thus, genetic exchange was taking
place between the two cell types.
Experiment through
•U-tube Experiment
•Performed U-tube experiment .
•Found that part of the cells on one
side of the U-tube were
prototrophs (could grow in
minimal medium).
Observed in
•Transduction has been found to
occur in a variety of prokaryotes,
including certain species of the
Bacteria: Salmonella, Escherichia,
Pseudomonas, Desulfovibrio,
Rhodococcus, Rhodobacter,
Staphylococcus, and Xanthobacter,
as well as Methanobacterium
thermoautotrophicum.

6. Transduction is the process by which
foreign DNA is introduced into a cell by a
virus or viral vector. Transduction is a
common tool used by molecular biologists
Whatistransduction?
common tool used by molecular biologists
to stably introduce a foreign gene into a
host cell's genome (both bacterial and
mammalian cells).
Whatistransduction

7. Transduction
Generalized transduction:
A bacterial virus, or bacteriophage,
transfers the DNA from one bacterial
cell to another
During a LYTIC infection, a transducing
Specialized transduction
Produced particles with both phage and host
DNA, linked in a single DNA molecule, from a
specific region of the chromosome (E. coli
phage )
Unlike the F plasmid that can
incorporate anywhere in the E. coli
During a LYTIC infection, a transducing
phage, such as P1 infecting E. coli,
accidentally packages a piece of the
bacterial chromosome into a virus
particle instead of its own viral DNA.
The phage carrying the bacterial
DNA then delivers it to the recipient
cell when it tried to infect again.
The injected bacterial DNA may
then be inserted into recipient
chromosome by homologous
recombinant.
incorporate anywhere in the E. coli
genome, lambda can only incorporate
into a specific site, called attλ. The gal
gene is on one side of attλ and the bio
gene (biotin synthesis) is on the other
side.
Sometimes when lambda come out
of the chromosome at the end of
the lysogenic phase, it crosses over
at the wrong point.
When this happens, a piece of the E.
coli chromosome is incorporated
into the lambda phage
chromosome

10. Significance
Altering the genetic characteristics through transfering
genetic material.
• For example: In specialised transduction the gal gene, a cell lacking
ability to metabolize galactose could aquire the ability .
It shows the evolutionary relationship between the
prophage and host bacterial cell.prophage and host bacterial cell.
Prophage can exist in a cell for a long period suggests a
similar possible mechanism for the viral origin of cancer.
It provides a way to study the gene linkage