BITO-111BIOTECHNOLOGY

Ayesha Masrur KhanNovember 2013

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Applications of Biotechnology

•Use of molds to produce antibiotics: ampicillin, amoxycillin, tetracyclin etc

•Therapeutic proteins/hormones •Monoclonal antibodies•Vaccines

Medicine

•Use of tissue culture to produce plants with desired traits •Pest, stress resistance plants to enhance agricultural

activity

Agriculture

•Cultured microorganisms to produce cheese, yogurt, wine, vinegar etc.

•Food testing for harmful toxins produces by microorganisms

•GM plants: Flavr Savr tomato, Bt cotton•Functional foods & nutraceuticals

High quality foods

•Tissue culture to mass produce and regenerate green plants/trees

•Biomass utilization by conversion into fuel (methane and ethanol byproducts)

Fuel and Fodder

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Applications of Biotechnology (cont’d)

•Waste/toxin affected water and land can be treated: Industrial effluents, pesticides, insecticides, oil spills etc. contribute to land, water and air pollution .

Pollution prevention

•Improvement of milk and meat production•Animal breeding to increase offsprings of a certain kind

Livestock Improvement

•Diagnosis : diseases, genetic predispositions to certain disorders, detection of inherited disorders in early stages.•Rational drug design•Pharmacogenomics•Gene therapy, stem cell therapy•Improvement of therapeutic protein drugs through protein engineering

Health and Molecular Medicine

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The Broad Picture of Life

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The Broad Picture of Life

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The Science behind Biotechnology

• Cell processes: Cell growth & metabolism, response & adaptation

• Parts of cells (animals & plants)

• DNA• Mutations• Genomes• Proteins• Transcription &

Translation

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The Central Dogma

The development of any living organism is the outcome of theaction of proteins. Proteins are produced as a direct result of DNA.

But how is DNA information translated into proteins?

1. Genetic code: Each DNA sequence corresponds to a specificsequence of amino-acids, the building blocks of proteins

2. Proteins synthesis is done in the cytoplasm of the cell, with amessenger from the DNA going to the appropriate location in thecell (Jacob and Monod)

3. DNA transcription mRNA translation Protein

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Biomolecules: Proteins, nucleic acids, enzymes(Essential part of life)

1. Structural Protein– Structural proteins are the bricks– Fibers

2. Transport Proteins– Carrier molecules or transport proteins– Haemoglobin

3. Messenger Proteins– Cells in one part of the body communicate with cells in another part of the body.– Hormones (Insulin)

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Biomolecules: Proteins, nucleic acids, enzymes(Essential part of life)

Primary structure of proteins: Proteins are polymers of amino acids. Amino acids are primary amines that contain an alpha carbon that is connected to an amino group (NH2), a carboxyl group (COOH), and a variable side group (R). The side group gives each amino acid its distinctive properties and helps to dictate the folding of the protein.

Linking an amino group to a carboxyl group on another amino acid createspolymers of amino acids. This is termed a peptide bond

-20 amino acids found in proteins (polar, non-polar & charged)-proteins and peptides are formed when ribosome & rest of the translation machinery link 10-10,000 amino acids together primary sequence

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Biomolecules: Proteins, nucleic acids, enzymes(Essential part of life)-cont’d

Secondary structure: Association of primary sequence (folding) leads to secondary structure. Involvement of hydrogen bonds, hydrophobic interactions, sulfhydryl linkages & ionic interactions.Common secondary structures: 1. Alpha helix2. Beta Sheet3. Random coils

Tertiary structure: Connection of separate secondary structures casing specific folding. Hydrogen bonds, hydrophobic interactions, disulfide linkages & ionic interactions stabilize the structure.

Quaternary structure: Arrangement of polypeptides forming complexes.

Example: Haemoglobin (shown in figure) has 4 subunits, each having Haeme groups (containing iron that binds the oxygen)

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Nucleic acidsNucleic acids: Ribonucleic acid (RNA) and Deoxyribonucleic

acid (DNA), serve as storage units for the hereditary information.

RNA and DNA are long polymers of only 4 nitrogenous bases- adenine, guanine, cytosine and thymine (or uracil for RNA)-a sugar, and a phosphate group.

The nucleotide structure can be broken down into 2 parts. The sugar-phosphate backbone and the base. All nucleotides share the sugar-phosphate backbone. Linking the monomer units using oxygen on the phosphate, and a hydroxyl group on the sugar forms nucleotide polymers.

The sugar in DNA, deoxyribose is called a pentose sugar because it has 5 carbon atoms.

The sugar in RNA is also a pentose sugar called ribose, and the one in DNA is deoxyribose (lacks oxygen at carbon no.2)

Moving to smaller yet significant things…

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Nucleic acids-cont’dAdenine (A) and Guanine

(G) are purines; two ring structure,

Cytosine (C) and Thymine (T) and Uracil (U) are pyrimidines; one ring structures and share a similar structure, but differ in their side groups.

Base pairing: Adenine forms two hydrogen bonds with thymine, cytosine forms 3 with guanine. The G to C pair is 33% stronger than the A to T pair due to the extra hydrogen bond.

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BITO-111 15Transcription of DNA to RNA to Protein