DNA cloning is the starting point for many genetic engineering approaches to biotechnology research.

1. DNA Cloning

2. DNA Cloning
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Isolation of DNA
Ligating the dna into a vector
Transformation of a host cell with the recombinant dna
Selection of host cells harboring the recombinant dna
Screening of cells for those harboring the recombinant
dna or producing the appropriate protein product

3. Cloning vectors
• Transport recombinant dna into a host cell
• a DNA molecule that carries foreign DNA
into a host cell, replicates and produces
many copies of itself and the foreign DNA

4. What cloning vectors must have
• 1.
have an origin of replication
• 2. be small
• 3. have several unique restriction
sites
• 4. Have selectable markers

5. Types of cloning vectors
• 1. bacterial vectors
Greatest variety of cloning vectors ( e. coli)

6. Plasmids- circular double
strands that are extra
chromosomal
• Functions:
1. Encode substance s for
antibiotic resistance
2. Bacteriocins
3. Physiological functions
4. Toxin- producing
5. Virulence plasmids

7. Role of plasmids in dna cloning
• Engineered with unique restriction sites
for insertion of foreign dna fragments

8. Types of cloning vectors
• 2. bacteriophage
• A virus that infects a bacterium
• Derived from a double strand genome that has a
single strand complementary ends of 12 nucleotides
that can base pair which forms a circular dna
molecule once inside the host cell

10. Types of cloning vectors
• 3. Cosmids
• Engineered hybrids of phage dna
and plasmids
• Plasmids with small portion of
bacteriophage vectors and
replication origin for replication in
bacterial hosts
• Used for cloning large dna
fragments

11. Types of cloning vectors
(for other organisms)
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4. Yeast artificial chromosomes (YAC)
For eukaryotic molecular studies
Has the following necessary components:
A. centromere-distributes the chromosome to the daughter
cells
• B. telomere- ensures that the end is correctly replicated and
protects against degradation
• C. autonomously replicating sequence- specific dna that
enable the molecule to replicate

13. Types of cloning vectors
(for other organisms)
• 5. Bacterial
artificial
chromosomes
(bac)
• Synthetic vectors
for large genome
project and
complex genomes

14. Types of cloning vectors
(for other organisms)
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6. Plant cloning vectors
Purposes:
A. generate resistance to disease, pests and herbicides
B. improve crop yield
C. quality and nutritional value
D. development of new ornamental plant characteristics
E. increase shelf life of common fruits and vegetables

16. • Commonly used plant vectors
• 1. tobacco mosaic virus
• 2. Ti or tumor inducing plasmid- agrobacterium
tumafaciens

17. Types of cloning vectors
(for other organisms)
• 7. Mammalian cell vectors
• First eukaryotic infecting virus to be
used
• Can infect the cells of several mammalian
species including monkey cells

18. What is your stand on cloning?