Recombinant DNA technology involves isolating a gene of interest and inserting it into a plasmid or bacterial chromosome. The modified bacteria can then be used to produce therapeutic proteins, vaccines, diagnose and screen for genetic diseases, and conduct gene therapy and DNA fingerprinting. Agricultural applications include creating herbicide-tolerant, pest-resistant, drought-tolerant and nutritionally enhanced crops. Environmental studies use recombinant DNA to identify microbes and study their roles.

4. Overview of recombinant DNA technology
Bacterial cell
Bacterial
chromosome
Plasmid
Gene of interest
DNA containing
gene of interest
Isolate plasmid.
Enzymatically cleave
DNA into fragments.
Isolate fragment
with the gene of
interest.
Insert gene into plasmid.
Insert plasmid and gene into
bacterium.
Culture bacteria.
Harvest copies of
gene to insert into
plants or animals
Harvest proteins
coded by gene
Eliminate
undesirable
phenotypic
traits
Produce vaccines,
antibiotics,
hormones, or
enzymes
Create
beneficial
combination
of traits

5. Applications of Recombinant DNA Technology
• Pharmaceutical and Therapeutic Applications
1. Protein synthesis
• Creation of synthetic peptides for cloning
• E.g. Human Insulin, Human Growth Hormone
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6. Ligase
E. Coli
E. Coli

7. 2. Vaccines
• Production of safer vaccines
• Subunit vaccines
• Genes of pathogens introduced into common fruits and
vegetables
• Injecting humans with plasmid carrying gene from
pathogen
– Humans synthesize pathogen’s proteins
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8. Recombinant vaccines can be broadly grouped into two kinds:
(i) Recombinant protein vaccines: This is based on production of
recombinant DNA which is expressed to release the specific protein
used in vaccine preparation
e.g. Hepatitis B, cholera, diphtheria, tetanus vaccines
(ii) DNA vaccines: Here the gene encoding for immunogenic protein is
isolated and used to produce recombinant DNA which acts as vaccine to
be injected into the individual.
e.g. Live vaccinia virus vaccine against small pox
-Vaccines

9. Production of recombinant vaccines involves the following steps:
(i) First and foremost, it is important that the protein which is crucial to the growth and development of the
causative organism be identified.
(ii) The corresponding gene is then isolated applying various techniques. Further to this, an extensive study
of the gene explains the gene expression pattern involved in the production of corresponding protein.
(iii) This gene is then integrated into a suitable expression vector to produce a recombinant DNA.
(iv) This rDNA is used as vaccines or is introduce into another host organism to produce immunogenic
proteins which acts as vaccines.
Advantages:
(i) Since it does not involve actual pathogen, recombinant vaccines is considered to be safe than the
conventional vaccines.
(ii) It induces both humoral and cellular immune response resulting in effective vaccination.
Risks involved:
(i) High cost of production.
(ii) Have to be stored at low temperature since heat destabilizes protein. Hence storage and transportation is
tedious.
(iii) Individuals with immunodeficiency may elicit poor immune response.
-Vaccines

10. 3. Genetic screening/ testing
• DNA microarrays used to screen individuals for inherited
disease caused by mutations
E.g. Huntington's disease
• Can also identify pathogen’s DNA in blood or tissues
4. DNA fingerprinting
• Identifying individuals or organisms by their unique DNA
sequence
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11. DNA fingerprinting

12. 5. Gene therapy
• Uses genes to treat or prevent disease.
• Missing or defective genes replaced with normal copies
• A number of viruses have been used for human gene
therapy, including retrovirus, adenovirus, lentivirus,
herpes simplex virus, vaccinia, pox virus, and adeno-
associated virus
• Trials are going on for treatment of cancer and other
genetic disorders using gene therapy
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13. Gene therapy

14. 6. Medical diagnosis
• Amniotic fluid or Chorionic villi (tiny, finger-shaped
growths found in the placenta) sampling is done during
pregnancy most commonly to check for disorders such
as Down’s syndrome. Also for diagnosis of other
metabolic or hematological disorders.
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15. 7. Xenotransplants
– Xenotransplantation, is the transplantation of animal
cells, tissues or organs into human body. Such cells,
tissues or organs are called xenografts or
xenotransplants
– A worldwide shortage of organs for clinical implantation causes
about 20–35% of patients who need replacement organs to die on
the waiting list. Certain procedures, some of which are being
investigated in early clinical trials, aim to use cells or tissues from
other species to treat life-threatening and debilitating illnesses such
as cancer, diabetes, liver failure and Parkinson's disease.

16. Applications of Recombinant DNA Technology
• Environmental Studies
– Most microorganisms have never been grown in a
laboratory
– Scientists know them only by their DNA fingerprints
• Allowed identification of over 500 species of bacteria
from human mouths
• Determined that methane-producing archaea are a
problem in rice agriculture
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17. Applications of Recombinant DNA Technology
• Agricultural Applications
– Production of transgenic organisms
• Recombinant plants and animals altered by addition of
genes from other organisms
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18. • Agricultural Applications
– Herbicide tolerance
• Gene from Salmonella conveys resistance to glyphosate
(Roundup™)
– Farmers can kill weeds without killing crops
– Salt tolerance
• Scientists have inserted gene for salt tolerance into
tomato and canola plants
• Transgenic plants survive, produce fruit, and remove
salt from soil
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19. • Agricultural Applications
– Freeze resistance
• Crops sprayed with genetically modified bacteria can
tolerate mild freezes
– Pest resistance
• Bt toxin
– Naturally occurring toxin harmful only to insects
– Organic farmers used to reduce insect damage to crops
• Gene for Bt toxin inserted into various crop plants
• Genes for Phytophthora resistance inserted into potato
crops
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20. • Agricultural Applications
– Improvements in nutritional value and yield
• Tomatoes allowed to ripen on vine and shelf life
increased
– Gene for enzyme that breaks down pectin suppressed
• BGH allows cattle to gain weight more rapidly
– Produce meat with lower fat content and produce 10%
more milk
• Gene for β-carotene (vitamin A precursor) inserted into
rice
• Scientists considering transplanting genes coding for
entire metabolic pathways
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21. Application of recombinant dna
technolgy
• Recombinant bacteria in Industry
• Recombinant bacteria in Medicine
• Recombinant bacteria in Agriculture
• Production of Transgenic animal
• Production of Transgenic plants
• Bioprocessing (A bioprocess is specific process that uses
complete living cells or their components (e.g., bacteria, enzymes,
chloroplasts) to obtain desired products.)