Introduction to Biotechnology

• Biotechnology is the use of living organisms or their products to make a product or solve a problem
• Biotechnology is an interdisciplinary field, involving biology, chemistry, computer science, engineering, and physics

Everyday Examples of Biotechnology

• GMO/GE foods, flu shots, insulin, antibiotics, monoclonal antibodies, wine, cheese, and pregnancy tests are examples of biotechnology

Historical Biotechnology

• Selective breeding involves choosing and breeding organisms for specific traits
• Plant domestication (10,500 BC) involved barley and wheat
• Animal domestication (9,000–7,000 BC) involved sheep and cows
• Fermentation (7,000–6,600 BC) involved alcohol from fruit/rice/honey
• Alexander Fleming discovered penicillin in 1928

Selective Breeding Examples

• Modern corn was bred from teosinte
• Dogs were bred from gray wolves (CANIS LUPUS)

Modern Biotech Milestones

• Gene cloning makes identical copies of genes
• Recombinant DNA combines DNA from different sources
• Stanley Cohen and Herbert Boyer altered an organism's DNA through genetic engineering in 1973
• The Human Genome Project (1990–2003) mapped all human genes

Biotech Applications

• Vaccines, diagnostics, high-yield crops, golden rice, pollution cleanup, and personalized medicine are applications of biotechnology

Products from Cloned Genes

• Insulin, growth hormone, clotting factors, monoclonal antibodies, and interferons are products from cloned genes

Types of Biotechnology

• Microbial, agricultural, animal, forensic, bioremediation, aquatic, and medical are types of biotechnology

Microbial Biotechnology

• Microbes are used to produce enzymes, vaccines, and medicines
• Recombinant insulin (HUMULIN) was approved in 1982

Agricultural Biotechnology

• Genetically engineered crops offer higher yield, better nutrition, and pest resistance
• The UN Food and Agriculture Organization predicts a 70% increase in food production needed by 2050

Animal Biotechnology

• Transgenic animals are engineered to produce human proteins (e.g., ATRYN from goats)
• Knockout animals have specific genes turned off to study function (e.g., MC4R in obese mice)

Forensic Biotechnology

• DNA profiling is used for solving crimes, paternity, and human remains identification
• Alec Jeffreys developed DNA profiling in 1988

Bioremediation Biotechnology

• Organisms are used to clean pollutants (e.g., oil spills)
• Examples include Exxon Valdez (1989) and Deepwater Horizon (2010)

Aquatic Biotechnology

• Engineered aquatic organisms include disease-resistant fish and growth hormone salmon
• Bioprospecting discovers useful compounds from marine life

Medical Biotechnology

• Biotechnology is used in diagnosis, treatment, prevention, gene therapy, and stem cell research

Biotech Industry Overview

• US & Europe: $132.7B revenue, $40B R&D, over 200,000 employees

Prokaryotic vs Eukaryotic Cells

• Prokaryotes have no nucleus or organelles (e.g., bacteria)
• Eukaryotes have a nucleus and organelles (e.g., plants, animals)

Prokaryotic Cell Structure

• Components: plasma membrane, ribosomes, capsule, nucleoid, and flagella

DNA Discovery Timeline

• Friedrich Miescher (1869) discovered DNA, called it "nuclein"

Griffith's Experiment (1928)

• Frederick Griffith showed transformation (dead S strain + live R strain = death)

Transformation

• Bacteria take up and incorporate DNA from surroundings

DNA Proven as Genetic Material

• Oswald Avery, Colin MacLeod, Maclyn McCarty (1944): DNA is the transforming factor

DNA Structure

• Nucleotide: sugar (deoxyribose), phosphate, nitrogen base (A, T, G, C)
• Bases: A-T (2 bonds), G-C (3 bonds)
• DNA is double-stranded and antiparallel

RNA vs DNA

• DNA: deoxyribose, A-T-G-C
• RNA: ribose, A-U-G-C

Franklin & Wilkins (1951)

• Rosalind Franklin and Maurice Wilkins produced X-ray crystallography data

Double Helix Model

• James Watson and Francis Crick (1953) modeled DNA structure

DNA Replication

• Semiconservative: each new DNA strand has one old and one new strand
• Enzymes: helicase, primase, DNA polymerase, and ligase
• Leading strand: continuous; Lagging strand: Okazaki fragments

Cell Division

• Mitosis: somatic cells → 2 identical daughter cells
• Meiosis: sex cells → 4 unique haploid cells
• Zygote is a fertilized egg (2n)

Central Dogma

• DNA → RNA → Protein

Transcription

• RNA polymerase reads DNA (3' → 5') to make mRNA (5' → 3')
• Transcription factors help RNA polymerase find promoter
• Ends at termination site → pre-mRNA

RNA Types

• mRNA: messenger
• tRNA: transfers amino acids
• rRNA: part of ribosomes
• RNAi: regulatory, non-coding

mRNA Processing

• Splicing removes introns and keeps exons
• 5' Cap helps ribosome bind
• 3' Poly-A tail provides stability and protects from degradation

Translation: Genetic Code

• Codon: 3 bases = 1 amino acid
• 64 codons, 20 amino acids
• Start codon: AUG (methionine)
• Stop codons: UAA, UAG, UGA

Translation: Ribosomes & tRNA

• Ribosomes: two subunits (large, small), with A, P, E sites
• tRNA: has anticodon + amino acid attachment

Translation Stages

• Initiation: ribosome binds to mRNA at start codon
• Elongation: tRNAs bring amino acids, peptide bonds form
• Termination: stop codon, release of protein