14. biotechnology Flashcards
biotechnology
The application of science and engineering in
the direct or indirect use of living organisms,
or parts or products of living organisms, in their
natural or modified forms
Recombinant DNA
The combination of DNA molecules from different biological sources into
a new DNA molecule
What are the 2 essential components for recombinant technology?
(1) Restriction enzymes
(2) Plasmid DNA – extra-chromosomal (often circular) piece of self-replicating DNA
restriction enzymes
DNA-cutting enzymes
Excise a piece of DNA from a chromosome using a restriction enzyme in order to transfer it.
only cut DNA at restriction sites
What does restriction enzyme cutting produce?
- blunt ends or
- staggered ends
able to recombine with any complementary DNA molecule.
DNA ligase
Enzyme that forms covalent bonds between blunt or staggered free ends of DNA to create rDNA
Cloning
Process of producing genetically identical copies of biological entities:
(1) DNA fragments (molecular cloning)
(2) Cells (cell cloning)
(3) Whole organisms
4 steps of cloning a DNA fragment
- Fragmentation
- Ligation
- Transformation
- Screening
Fragmentation
use the same restriction enzymes to cut and separate pieces of DNA from a sample and a plasmid
Ligation
Attach the 2 fragments of DNA by base pairing, then use DNA ligase to form covalent bonds to create the recombinant plasmid.
vector
DNA molecule that carries foreign DNA into a host
cell, replicates inside the
host cell, and produces many copies of itself.
ex. bacterial plasmids, bacteriophages
selectable marker
gene that confers a trait suitable for artificial selection
Transformation
Insert the newly formed rDNA into cells
- Involves increasing plasma membrane permeability using electric shocks or ion concentrations
screening
select cells successfully transformed
with the recombinant DNA.
PCR
Polymerase Chain Reaction
rapid and versatile method for amplifying target DNA sequences
PCR: 3-Step Process
- Denaturation – Heating to 94-96°C so DNA separates into 2 single-strands of DNA.
- Annealing – Cooling to 50-70°C to allow primers (short nucleotide sequences) to bind (or anneal) to complementary bases at opposite ends of the target sequence.
- Elongation – Heating to 70-75°C to allow Taq polymerase (an enzyme) to bind to the 3’ ends of each
primer and add nucleotides to synthesize 2 new complementary strands of DNA (using the original strands as templates).
Transgenic animals
Animal in which genetic engineering techniques have been used to introduce, remove, or modify specific parts of its genome.
Whole Animal Cloning
One Method: Nuclear Transfer- Transplanting the nucleus from a somatic cell into an ovum
that has had its nucleus removed.
Applications of Biotechnology
A. To enhance production or food quality traits –
Crops and Animals.
B. To improve Animal Health.
C. To enhance human-animal interactions.
D. To produce products for Human Health & Medicine
Gene Pharming
transgenic livestock produce biologically active pharmaceuticals for human medicine
GMO
genetically modified organisms
Any organism that has 1 or more gene(s) altered using rDNA technology.
pro and cons of GMO
pro: GMOs provide a strategy for increasing global food production by: - reducing crop losses, - increasing crop yields, and - maximizing land conservation
cons: GMOs are pursued for profit, they decrease biological diversity, and the release of transgenic plants and organisms may have a negative impact on the environment
Human-Animal Interactions
Use of biotechnology to enhance human-animal
interactions:
(1) Unique traits for pets
(2) Hypoallergenic pets
ex. glofish
Xenotransplantation
development of transgenic animals that could donate organs to humans
- Pigs – likely the most suitable donor animal for humans
(1) Similar organ sizes
(2) Similar anatomy & physiology
(3) Pigs have short reproductive cycles with large litters
(4) Pigs grow rapidly
Biomedical Applications
Animals Engineered to Serve as Models to Help Study and Potentially Treat Human Diseases
Animal Engineered as Sources of Transplant Cells, Tissues, and Organs
Genetic Testing
Genetic tests involve direct examination of DNA molecules from blood or other tissue to diagnose a genetic disorder
Gene Therapy
Technique for correcting defective genes responsible for disease by inserting, altering, or removing genes within an individual’s cells.
Pharmacogenomics
The study of how an individual’s inherited variation in
different genes affects drug response.
Drug and Vaccine Production
Biopharmaceuticals are produced using biotechnology; particularly rDNA in bacteria
Vaccines for animals have been approved and used,
including vaccines for: rabies, baby pig scours, foot rot, sheep measles, and
infectious bursal disease.
Recombinant bovine somatotropin (rBST)
synthetic bovine growth hormone produced by rDNA technology
Biotechnology and Pest Management
Several bacteria have been genetically altered to improve their ability to kill or repel pests
which government agencies regulate genetically engineered crop?
- FDA- Food and Drug Administration
- EPA- Environmental Protection Agency
- APHIS- Animal and Plant Health Inspection Service
FDA’s 7-Step Review Process for
new animal drug approval
1) Product definition
2) Molecular characterization of the construct
3) Molecular characterization of the GE animal lineage
4) Phenotypic characterization of the GE
animal
5) Durability Plan
6) Environmental & food/feed safety
7) Claim validation
