1. GROUP MEMBER
M.USMAN FAZIL
ANOUSHA KHAN
FATIMA SIDRA
Course Content:
Genetic Engineering and Biotechnology
Topic :
Genomic Library
Submitted to:
Sir Kashif Rahim
3. Genome
o An organism's complete set of DNA is called its genome.
o Every single cell in the body contains a complete copy of the
approximately 3 billion DNA base pairs, or letters, that make up
the human genome.
o The genome is the entire set of genetic instructions found in a
cell . In
humans, the genome consists of 23 pairs of chromosomes,
found in the nucleus
o Each set of 23 chromosomes contains approximately 3.1 billion
bases of DNA sequence.
4. GENOMIC LIBRARY
DNA molecules is called a genomic library. Such libraries are the
starting point for sequencing entire genomes such as the human
genome
A genomic DNA library is a collection of DNA fragments that make up
the full-length genome of an organism. A genomic library is created by
isolating DNA from cells and then amplifying it using DNA cloning
technology.
5. The DNA is stored in a population of identical vectors, each containing a
different insert of DNA.
In order to construct a genomic library, the organism's DNA is extracted from
cells and then digested with a restriction enzyme to cut the DNA into
fragments .
Genomic libraries are commonly used for sequencing applications play an
important role in the whole genome sequencing of several organisms,
including the human genome and several model organisms.
6. GENOMIC Library
1. cDNA library
2. Genomic Library
DNA library
cDNA library contains the cloned complementary DNA of
total mRNA of an organism.
cDNA library
It contains the cloned fragments of the entire genome of an
organism. The genomic DNA library is larger than the
cDNA library.
7.
8. Genomic library construction
Construction of a genomic library involves creating many recombinant
DNA molecules.
An organism's genomic DNA is extracted and then digested with
a restriction enzyme.
Steps for creating a genomic library from a large
genome.
1 Extract and purify DNA.
2 Digest the DNA with a restriction enzyme. This creates fragments that are
similar in size, each containing one or more genes.
9. 3. Insert the fragments of DNA into vectors that were cut with the same
restriction enzyme. Use the enzyme DNA ligase to seal the DNA fragments into
the vector. This creates a large pool of recombinant molecules.
4.These recombinant molecules are taken up by a host bacterium
by transformation, creating a DNA library.
10. Steps of Genomic Library Construction
1.Isolation of DNA from Cell
2.Digestion into Small fragments
3.Introduction into suitable vectors
4.Insertion into Bacteria
5.DNA Isolation
6.Collection of Genomic DNA library
11. 1.Isolation of DNA from Cell
Eukaryotes
To create a human genome library areasercher begin by extracting
and purifying DNA from human cell
Prepare nuclei cell, remove Protein, lipids And other unwanted molecule by
Protease enzyme.Digestion and phase Extraction
Prokaryotes
In prokaryotes extracted the DNA directly from the cell.
2.Digestion into Small Fragments
The DNA is therefore digested with restriction enzymes which cut the
DNA at specific sequence
Restriction enzymes Cut the DNA into 1000s Of small fragments each of
which may contain One or more genes
12. The organisms with very small genomes the digested fragments can be
seprated by Gel Electrophoresis.
The seprated fragments can then be excised and cloned into the vector
Seprately.
3.Introduction into suitable Vectors
Each fragment is a different and have a unique DNA sequence.
Inserted into suitable vectors such as Plasmid and bacteriophages
To create the library, each fragment must be inserted into loops of
DNA called plasmids
13. o The plasmids are digested with the restriction enzymes and then
sealed to human DNA using DNA ligase enzyme the resulting
molecules are “recombinanat”
The recombinant DNA molecule are added to bacteria, and the
bacteria are made to take up the DNA
When bacteria have taken up the DNA, the entire collection of
cells and DNA represents a human genome library.
Several kind of Vectors commonly used for genomic libraries
and they insert size that each generally holds.
14.
15. 4.Insertion into Bacteria
 Inserted into the Host Bacteria Escherchia Coli.
The transformation is then spread on agar plates and
incubated overnight.
The titer of the transformation is determined by counting
the number of colonies present on the plates.
These vectors generally have a selectable marker
allowing the differentiation of clones containing an insert
from those that do not.
By doing this test we can make adjustments as needed to
ensure they get the desired number of clones for the
library.
They produces Colone for the original Genome.
16.
17. 5.DNA Isolation
 In order to construct a genomic library, the organism's DNA is extracted
from cells and then digested with a restriction enzyme to cut the DNA into
fragments of a specific size. The fragments are then
inserted into the vector using DNA ligase.
6.Collection Of Genomic DNA Library
A genomic library is a collection of overlapping segments of genomic DNA,
cloned into a backbone vector, which statistically includes all regions of the
genome of an organism. The resulting cloned DNA is then transformed into
a suitable host cell line.
18.
19. Applications of Genomic Library
1. Genomic library construction is the first step in any DNA
sequencing projects.
2. Genomic library helps in identification of the novel
pharmaceutically important genes.
3. Genomic library helps in identification of new genes which
were silent in the host.
4. It helps us in understanding the complexity of genomes.
5. Serving as a source of genomic sequence for generation
of transgenic animals through genetic engineering .
6. Study of the function of regulatory sequences in vitro.
7. Study of genetics