Introduction to Biotechnology

Introduction to Biotechnology

• This PowerPoint presentation is intended to supplement lectures, not replace textbooks
• Students must read the recommended textbooks for a thorough understanding and exam preparation

Learning Objectives

• Students should be able to define biotechnology after the lecture
• Define Recombinant DNA technology, its steps, and the roles of restriction endonucleases, vectors, and plasmids
• Describe PCR and Blotting techniques, including their steps and clinical significance

What is Biotechnology?

• Biotechnology is the manipulation of living organisms and biological materials to address human needs
• Examples include:
  • Yeast in bread making and alcohol production
  • Using beneficial bacteria to produce antibiotics like penicillin and vaccines
  • Cloning plants and animals
  • Stem cell research

Some Discoveries

• Antony van Leeuwenhoek: Discovered bacteria using a simple microscope
• Gregor Mendel: Conducted early genetics experiments using pea plants, considered a founder of genetics
• Louis Pasteur: Created the rabies vaccine
• Robert Hooke: Invented the compound light microscope and first observed cells in cork
• James Watson & Francis Crick: Identified the double helix structure of DNA using X-ray photographs.
• Meselson and Stahl: Proposed the semi-conservative model of DNA replication
• Paul Berg: Developed recombinant DNA technology, allowing the insertion of genetic material from one organism into another

Recombinant DNA Technology

• Recombinant DNA technology transfers genes/DNA segments from one organism to another
• A crucial application is creating large quantities of valuable biomolecules like growth hormones, insulin, immunoglobulins, vaccines, and clotting factors.

Recombinant DNA Technology Steps (Diagram)

• Cutting DNA using restriction enzymes (molecular scissors)
• Ligation of cut DNA fragments into vectors (carrying DNA fragment)
• Transferring recombinant vectors into a host organism
• Amplification of recombinant DNA (copying)

Some Important Terms

• Restriction Endonucleases: Enzymes that cut DNA at specific nucleotide sequences (restriction sites) – crucial for recombinant DNA technology
• Examples: EcoRI (from Escherichia coli) and TaqI (from Thermus aquaticus)
• Vectors: DNA carriers that introduce a gene of interest into bacteria
• Examples include plasmids, bacteriophages, or cosmids
• Plasmids: Small, circular, extra-chromosomal DNA molecules in bacteria; used in recombinant DNA technology due to independent replication capacity, and often associated with antibiotic resistance in bacteria

Polymerase Chain Reaction (PCR)

• A technique to produce large amounts of DNA without using living cells
• Key steps: Denaturation, Renaturation (Annealing), Extension (Synthesis)

Uses of PCR

• Prenatal diagnosis (Sickle cell anemia, Thalassemia)
• Detecting viral infections (HIV, COVID-19)
• Diagnosing bacterial infections (Tuberculosis)
• Diagnosing cancer (Cervical cancer)

Blotting Techniques

• Techniques for identifying and immobilizing DNA, RNA, or proteins
• Types include:
  • Southern Blotting (identifying DNA)
  • Northern Blotting (identifying RNA)
  • Western Blotting (identifying proteins)

Additional Information

• Dolly, the sheep, was the first mammal cloned from diploid cells (1997)