Biotech 2-Applications Flashcards
class 12
Biotechnology – Overview
- Industrial-scale production of biopharmaceuticals & biologicals. - Uses genetically modified microbes, fungi, plants, and animals. - Applications include: - Therapeutics & diagnostics - Genetically modified crops - Processed food - Bioremediation & waste treatment - Energy production - Three Critical Research Areas in Biotechnology: 1. Developing better catalysts (e.g., improved microbes or enzymes). 2. Creating optimal conditions for catalyst efficiency. 3. Downstream processing for purification of proteins/organic compounds.
Biotechnological Applications in Agriculture
- Three main approaches to increasing food production: 1. Agro-chemical based agriculture – Uses fertilizers & pesticides but is expensive for farmers. 2. Organic agriculture – Relies on natural fertilizers & pest control but may not meet food demand. 3. Genetically engineered crops – Biotech-driven solutions for higher yield & resistance. - Green Revolution: Increased food production but could not fully meet population demands. - Tissue Culture – Micropropagation: - Regeneration of whole plants from explants (plant parts) in sterile nutrient media. - Totipotency: Ability of a single plant cell to develop into an entire plant. - Micropropagation: Produces thousands of genetically identical plants (somaclones). - Applications: - Used for commercial propagation of tomato, banana, apple, etc. - Recovery of virus-free plants using meristem culture (banana, sugarcane, potato). - Somatic Hybridisation: - Fusion of protoplasts (naked plant cells without walls) from two different plant species. - Produces somatic hybrids with desirable traits. - Example: Pomato (Tomato + Potato hybrid) – but lacked commercial viability.
Biotechnology – Overview
- Industrial-scale production of biopharmaceuticals & biologicals. - Uses genetically modified microbes, fungi, plants, and animals. - Applications include: - Therapeutics & diagnostics - Genetically modified crops - Processed food - Bioremediation & waste treatment - Energy production - Three Critical Research Areas in Biotechnology: 1. Developing better catalysts (e.g., improved microbes or enzymes). 2. Creating optimal conditions for catalyst efficiency. 3. Downstream processing for purification of proteins/organic compounds.
Biotechnological Applications in Agriculture
- Three main approaches to increasing food production: 1. Agro-chemical based agriculture – Uses fertilizers & pesticides but is expensive for farmers. 2. Organic agriculture – Relies on natural fertilizers & pest control but may not meet food demand. 3. Genetically engineered crops – Biotech-driven solutions for higher yield & resistance. - Green Revolution: Increased food production but could not fully meet population demands. - Tissue Culture – Micropropagation: - Regeneration of whole plants from explants (plant parts) in sterile nutrient media. - Totipotency: Ability of a single plant cell to develop into an entire plant. - Micropropagation: Produces thousands of genetically identical plants (somaclones). - Applications: - Used for commercial propagation of tomato, banana, apple, etc. - Recovery of virus-free plants using meristem culture (banana, sugarcane, potato). - Somatic Hybridisation: - Fusion of protoplasts (naked plant cells without walls) from two different plant species. - Produces somatic hybrids with desirable traits. - Example: Pomato (Tomato + Potato hybrid) – but lacked commercial viability.
Genetically Modified Organisms (GMOs) in Agriculture
- Genetically Modified Organisms (GMO): Organisms (plants, bacteria, fungi, animals) whose genes have been altered using biotechnology. - Advantages of GM Crops: 1. Tolerance to abiotic stresses – Resistant to cold, drought, salt, heat. 2. Reduced pesticide usage – Less reliance on chemical pesticides. 3. Reduced post-harvest losses – Prevents spoilage and increases shelf life. 4. Improved soil fertility – Increased efficiency of mineral usage by plants. 5. Enhanced nutritional value – Golden rice enriched with Vitamin A. - Other Uses: GM plants are designed for industrial applications (e.g., starch, fuels, pharmaceuticals).
Pest-Resistant Crops – Bt Cotton
- Bt Cotton: A genetically modified crop engineered to resist insect pests. - Source of Resistance: Bacillus thuringiensis (Bt) – A bacterium that produces insecticidal Bt toxin. - Mechanism of Action: 1. Bt bacterium forms protein crystals (toxic to insects) during its growth. 2. Bt toxin exists as inactive protoxins. 3. Insect ingestion activates the toxin due to alkaline pH of the insect’s gut. 4. Activated toxin binds to midgut epithelial cells, creating pores. 5. Cell swelling & lysis occur, leading to insect death. - Targeted Pests and Bt Genes: - cryIAc & cryIIAb → Controls cotton bollworm. - cryIAb → Controls corn borer. - Crop Examples: Bt Cotton, Bt Corn, Bt Rice, Bt Tomato, Bt Potato, Bt Soybean.
Pest-Resistant Plants and RNA Interference (RNAi)
- Problem: The nematode Meloidogyne incognita infects tobacco plant roots, causing severe yield reduction. - Solution – RNA Interference (RNAi): - RNAi is a cellular defense mechanism in all eukaryotic organisms. - It involves the silencing of specific mRNA to prevent translation. - How RNAi Works: 1. A double-stranded RNA (dsRNA) molecule is introduced into the host. 2. The dsRNA binds to the target mRNA, preventing its translation. 3. This stops the production of essential nematode proteins, killing the parasite. - How was RNAi used to protect plants? 1. Nematode-specific genes were inserted into the plant using an Agrobacterium vector. 2. The plant produced both sense and antisense RNA, forming a dsRNA molecule. 3. This triggered RNAi, silencing the nematode’s vital genes. 4. As a result, the nematode could not survive in the transgenic plant. - Outcome: The transgenic tobacco plant was protected from nematode infection, ensuring higher crop yield. The source of this complementary RNA could be from an infection by
viruses having RNA genomes or mobile genetic elements (transposons)
that replicate via an RNA intermediate.
Recombinant DNA Technology in Medicine
Currently, 30 recombinant therapeutics are approved globally, 12 of which are marketed in India.
🔹 Why is this important?
Recombinant drugs improve treatment safety and efficacy.
Reduces dependency on animal-derived drugs, which may cause allergic reactions.
Genetically Engineered Insulin
arlier, insulin was extracted from pancreas of slaughtered cattle and pigs.
Animal-derived insulin caused allergies in some patients.
🔹 Structure of Insulin:
Composed of two polypeptide chains:
Chain A & Chain B linked by disulfide bonds.
In humans, insulin is synthesized as a pro-hormone containing an extra stretch called the C-peptide, which is removed during maturation.
🔹 Recombinant Insulin Production (1983, Eli Lilly)
Two DNA sequences for chains A & B were synthesized.
These sequences were introduced into plasmids of E. coli.
E. coli produced the chains separately.
The chains were extracted and combined by forming disulfide bonds to create functional human insulin.Insulin CANNOT be orally administered as it would be digested by proteases in the stomach.
Gene Therapy
What is Gene Therapy?
A collection of methods to correct a genetic defect by inserting functional genes into a person’s cells or tissues.
Used to replace a defective gene with a normal functional gene.
🔹 First Successful Gene Therapy (1990)
Target: A 4-year-old girl suffering from Adenosine Deaminase (ADA) Deficiency-called SCID(SEvere combined Immunodeficiency )
ADA Function:
Essential for immune system function.
ADA deficiency leads to a severely compromised immune system.
🔹 Treatment Methods for ADA Deficiency:
Bone marrow transplantation (limited success).
Enzyme replacement therapy (injections of functional ADA, but not a permanent cure).
Gene Therapy Approach:
Lymphocytes extracted from the patient’s blood.
A functional ADA cDNA introduced using a retroviral vector.
Genetically engineered lymphocytes reinfused into the patient.
🔹 Limitations of Lymphocyte-Based Gene Therapy:
Lymphocytes are not immortal, so the treatment is temporary.
Permanent cure may be possible if the ADA gene is introduced into embryo-stage cells.
Advanced Molecular Diagnostic Techniques:
Recombinant DNA Technology
Polymerase Chain Reaction (PCR)
Enzyme-Linked Immunosorbent Assay (ELISA)
Polymerase Chain Reaction (PCR) in Disease Diagnosis
Why is PCR important?
Detects very low concentrations of bacteria or viruses before disease symptoms appear.
Helps in early-stage diagnosis of genetic disorders and cancers.
🔹 How does PCR work?
Amplification of Nucleic Acid:
PCR amplifies DNA of pathogens, even if present in minute amounts.
This allows early detection before the infection spreads significantly.
Applications of PCR:
Detecting HIV in suspected AIDS patients.
Identifying mutations in genes of suspected cancer patients.
Diagnosing genetic disorders by detecting mutations in DNA.
Autoradiography for Genetic Disorder Detection
A single-stranded DNA or RNA probe (tagged with a radioactive molecule) is used.
The probe hybridizes to its complementary DNA in a clone of cells.
Detection by Autoradiography:
If the gene is mutated, the probe will not bind, and the clone will not appear on the photographic film.
If the gene is normal, the probe will bind and appear on the film.
🔹 Why is this useful?
Helps detect mutated genes that cause genetic disorders.
Allows early genetic screening for hereditary diseases.
Enzyme-Linked Immunosorbent Assay (ELISA)
Principle:
Based on antigen-antibody interaction.
🔹 How does ELISA detect infections?
Direct Detection:
Detects antigens (proteins, glycoproteins, etc.) produced by the pathogen.
Indirect Detection:
Detects antibodies produced by the host against the pathogen.
🔹 Applications:
Used for diagnosing HIV, Hepatitis, and other infections.
Helps in early-stage detection before symptoms appear.
What are Transgenic Animals?
Definition:
Animals whose DNA has been manipulated to possess and express an extra (foreign) gene.
Examples: Transgenic rats, rabbits, pigs, sheep, cows, fish.
Over 95% of transgenic animals are mice.
🔹 Purpose of Creating Transgenic Animals:
To study gene regulation and development.
To develop models for human diseases.
To produce biological products (medicines, proteins, etc.).
To test vaccine safety.
To conduct chemical/toxicity testing.
ransgenic Animals for Studying Normal Physiology
Why are they used?
Help in understanding how genes are regulated and their impact on body functions and development.
Example: Insulin-like Growth Factor (IGF).
Scientists introduce genes that alter IGF formation to study its biological role.
Helps understand growth processes in living organisms.
Transgenic Animals in Disease Research
Purpose:
Designed to model human diseases.
Helps understand how genes contribute to disease development.
Assists in testing new treatments.
🔹 Diseases Studied Using Transgenic Models:
Cancer
Cystic Fibrosis
Rheumatoid Arthritis
Alzheimer’s Disease
Transgenic Animals for Producing Biological Products
Why is this important?
Some medicines for human diseases contain biological products, which are expensive to produce.
Transgenic animals can be genetically modified to produce these useful biological substances.
🔹 Examples:
α-1-antitrypsin protein → Used to treat emphysema.
Phenylketonuria (PKU) & Cystic Fibrosis Treatments → Attempts are being made to use transgenic animals.
Rosie – The First Transgenic Cow (1997)
Produced human protein-enriched milk (2.4g of human alpha-lactalbumin per liter).
More nutritionally balanced for human babies than regular cow milk.
ransgenic Animals for Vaccine Safety Testing
Why use transgenic animals?
Vaccines must be tested for safety before human use.
Transgenic mice are developed to test vaccine safety.
Example: Polio vaccine testing in transgenic mice.
If successful, transgenic mice could replace monkeys in vaccine safety tests.
Transgenic Animals for Chemical Safety Testing (Toxicity Testing)
Purpose:
Used for testing drug and chemical toxicity.
Transgenic animals carry genes that make them more sensitive to toxic substances.
🔹 How it Works:
Transgenic animals are exposed to toxic substances.
Effects are studied to determine safety.
Faster results compared to traditional toxicity testing methods.
🔹 Benefits:
Reduces time needed for toxicity testing.
Helps in drug development and environmental safety studies.
Regulatory Body in India:
GEAC
GEAC (Genetic Engineering Approval Committee)
Decides the validity of genetic modification research.
Ensures safety before GM organisms are introduced for public services. Biopiracy and bioethics
Patents and Biopiracy Issues
Basmati Rice Patent Controversy (1997)
A US company obtained a patent for a ‘new’ variety of Basmati rice.
This variety was actually derived from Indian farmers’ traditional Basmati rice.
The patent restricted others from selling similar varieties internationally.
Other Biopiracy Examples:
Turmeric and Neem patents granted to foreign companies based on Indian traditional knowledge.
If India does not contest these patents, foreign companies may profit from Indian bio-resources unfairly.
India’s Actions Against Biopiracy:
Indian Patents Bill – Second Amendment
Protects traditional knowledge and bio-resources from being patented unfairly.
Includes provisions for emergency use and R&D support.
International Laws & Agreements
Nations are implementing stronger legal frameworks to prevent biopiracy.
Encouraging traditional knowledge documentation to prevent foreign patents.
overview of biotechnology
🔹 Definition:
Biotechnology involves using microbes, plants, animals, and their metabolic machinery to develop useful products.
🔹 Major Techniques in Biotechnology:
Tissue Culture – Growing plant cells in vitro to create new varieties.
Somatic Hybridisation – Fusion of protoplasts from different species to form hybrids.
Recombinant DNA Technology – Modifying DNA sequences to transfer genes and introduce new traits.
🔹 Genetically Modified Organisms (GMOs):
Organisms modified using non-natural gene transfer methods like recombinant DNA technology.
Transgenic Animals and Disease Research
Definition:
Animals genetically engineered to express new traits or study diseases.
🔹 Applications of Transgenic Animals:
Disease Models – Used to study diseases like cancer, cystic fibrosis, rheumatoid arthritis, Alzheimer’s.
Understanding Gene Function – Helps researchers study how genes contribute to diseases.
Biopharmaceutical Production – Producing human proteins like α-1-antitrypsin (used for emphysema treatment).
Vaccine and Drug Testing – Testing polio vaccine safety using transgenic mice.
