PLASMAIDS AND TRASPOSABLE ELEMENTS AS BIOTHECHNOLOGY TOOLS

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MANGALAYATAN UNIVERSITY
(Institute of Biomedical Education And Research)
PLASMAIDS AND TRASPOSABLE
ELEMENTS AS
BIOTHECHNOLOGY TOOLS
GROUP :03 (BIO-TECH 2ND
SEM)
Date-15/04/2010
•Divya Srivastava (2009EBT002)

2. ContentsContents
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INTRODUCTION OF PLASMIDS ------------ DIVYAINTRODUCTION OF PLASMIDS ------------ DIVYA
• DNADNA
• PLASMIDSPLASMIDS
• DIFFERENCE AMONG THE PLASMIDSDIFFERENCE AMONG THE PLASMIDS
• CLASSIFICATION OF PLASMIDSCLASSIFICATION OF PLASMIDS
• CHARACTERISTICS OF SOME BACTERIAL PLASMIDSCHARACTERISTICS OF SOME BACTERIAL PLASMIDS
• REPLICATION IN PLASMIDREPLICATION IN PLASMID
• HOW PLASMID IS A BIO-TECHNOLOGY TOOLHOW PLASMID IS A BIO-TECHNOLOGY TOOL
TRANSPOSABLE ELEMENTS ----------- ABHISHEKTRANSPOSABLE ELEMENTS ----------- ABHISHEK
• INSERTION SEQUENCESINSERTION SEQUENCES
• TRANSPOSONSTRANSPOSONS
• RETRO ELEMENTSRETRO ELEMENTS
• MACHANISMMACHANISM
• USESUSES

3. DNA
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• DNA stores genetic informations of most living
organisms.
• In prokaryotes DNA is present in the form of nucleoid.
• In eukaryotes DNA is present in nucleus as a part of
chromosomes.
• Some other genetic elements are found in prokaryotes
and eukaryotes these are called plasmids.

4. PLASMIDS
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In 1952 SIR J. LEDERBERG gave this term PLASMID.
It was known for a Extra chromosomal hereditary determinant.
Now this term is used for those accessory DNA circles, which are found
in bacteria in addition to the main chromosome.
They are present in some living organelles like mitochondria eukaryotes.
In bacteria plasmids can be regarded as extra nuclear genetic material.

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6. Difference among plasmids
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Plasmids differ among themselves in their characteristicsPlasmids differ among themselves in their characteristics
and share the following general properties:-and share the following general properties:-
1. They are genetic elements made up of DNA
2. They are smaller than and separate from the main chromosome
.
3. They are capable of replication.

7. Some other properties of plasmid
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• Control of bacteria conjugation.
• Reversible insertion in bacterial chromosome
• Transferable from one bacterium to another.

8. Classification of plasmids
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Three types of plasmids:-
• F or sex factor:- transfer of genetic materials from one strain
to other .
• R factor:- responsible for drug resistance.
• Col factor:- responsible for colic in production.

9. THE F FACTOR OR SEX FACTOR
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• F factors are known as sex factor

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THE R FACTOR OR RESISTANCE TRANSFER
FACTOR
• Resistance or R–plasmids:-
Contain genes or gene cassettes that confer a selective
advantage to the bacterium harboring them, such as the
ability to make the bacterium antibiotic resistant, i.e.,
resistant against antibiotics or poisons. Historically they
were known as R–factors.

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Col–plasmidCol–plasmid
•There are many bacterial strains that
produce proteinaceous toxins known as bacteriocin, which are
lethal to other strains of the same genus.
•The Bacteriocins producing genes are present not
in chromosomes, but in special plasmids known as Bacteriocins
factor.
•Bacteriocins are already isolated from Escherichia
coli (Colicin), Pseudomonas aeruginosa (Pyocin) and others.
• Several Col–plasmids like Col B, Col E, Col I, Col V have been
recognized and they produce different types of Colicin. Some of
the Col–plasmids are conjugative (e.g., Col B, Col V) while
others are non–conjugative (e.g., Col E) and are non–
transmissible by their own means.

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Characteristics of some bacterial plasmid
plasmids characteristics
F , RI , Col Fertility
Col EL bacteriocin production
R6 heavy metal resistance
Ent enterotoxin production
Com Metabolism of camphor
Ti(in Agro bacterium tumefaciens) tumorigenicity in plants

14. REPLICATION IN PLASMID
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DNA plasmid replicate in semi conservative manner.
Initiation of replication is controlled by the plasmid genes.
Other stages are controlled by bacterial gene.
Plasmid replication is absolute in bacterial control.

15. How plasmid acts as
biotechnology tool
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17. TRANSFER OF PLASMIDSTRANSFER OF PLASMIDS
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Plasmids also have the ability of transferring themselves from one
bacterium to other .
When transfer occurs, one of the two strands of plasmids DNA is
nicked(broken) at a site called origin of transfer which is Ori-T.
The linear strand thus formed moves to the recipient bacteria.
The single strands in donor as well as in recipient cell will then
synthesize complementary strands so that DNA plasmids are
reconstituted in both the cell.

18. TRANSPOSABLE ELEMENTS
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• In prokaryotic or eukaryotic genomes certain
sequencing capable of moving from one site to
other are called transposable elements.
They include:
• insertion sequences.
• transposons.
• retro elements.

19. INSERTION SEQUENCES
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These are capable of moving within the genome through illega limaterecombination

20. TRANSPOSONS
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They are extra chromosomal elements which are transposable and can occupy
different sites on main DNA.
In maize they are described as controlling elements due to their control on
expression of Genes

21. TRANSPOSONS IN PROKARYOTES
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The term was used in 1974 by R.W. Hedges and A.E.
Jacob of Hammersmith hospital in London.
A genetic element which can move from one molecule to
other and carries resistance for anti-biotic amphicillin, the
transfer of such antibiotic resistance from one plasmid to
other proves the transfer of DNA segment called
TRANPOSON

22. TRANSPOSON IN EUKARYOTES
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In eukaryotes they are classified into four types:
• those with long terminal direct repeats.
•those with long terminal inverted repeats.
• those with short terminal inverted repeats.
• those without terminal repeats.

23. RETROELEMENTS
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Retro elements are those nucleic acid sequences, which either
originate partly or fully, or propagate through, reverse
transcription.
These retro elements are classified into:
•Viral retro elements
•Non-viral retro elements.

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NON VIRAL RETROELEMENTS
NON-Viral:The non-viral retro elements include
retrotransposons, which resemble transposons except
that they have RNA origin.
They have:
LTR(long terminal repeat)sequences needed for
transposition.
• Primer binding site.
• Promoter
• Processing signal.

25. Mechanism
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Uses of transposons
As a genetic markers: They are used as
genetic markers because they change the pattern
of restriction fragments obtained after digestion
with specific endonucleases.
Mutagenesis:Since it is clear that
transposons transpose to new sites at certain
frequencies, one might expect that you
"mutagenize" a strain by taking a strain carrying
the transposon (in a site considered
"uninteresting" in terms of the system being
studied) and looking for cases where the Tn has
moved and generated an "interesting" mutation

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Cleanliness: As a mode of mutagenesis,
transposons are relatively clean; that is, in
contrast to other forms of mutagenesis they do
not cause a large number of alterations in the
genome.
Transposons Tagging - The
transposable elements (TEs), in some cases,
have been effectively utilized for isolation of
genes, when the gene product is unknown. In
this case a transposons works as a mutagen
and therefore as a gene tag.

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Plasmid insertion:
Plasmid insertion into chromosomes:
The sites at which plasmids insert into the
bacterial chromosome are at or near insertion
sequence in the chromosome.

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After preparing this seminar we come to know what plasmid is , how it is related with
transposons , plasmids are important for bacterial conjugation and it provides drug
resistance, transposons are jumping genes.

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