Agenda 4/8 Biotech Intro Uses for Bacteria and Viruses Phage vs. Gene Therapy Homework Chp 20 reading and notes DNA recombination video and notes Molecular Biology Video and Notes Turn in: Nothing?

Why is biotechnology important? By definition, biotechnology is using biological tools to improve the quality of life in a society With your groups, brainstorm 6 different biotechnology ‘tools’

Using Bacteria and Viruses In Biotechnology Bacteria: unicellular, prokaryotic organisms that are 0.2-10 microns Examples:? Viruses: acellular infectious agents made of nucleic acid and protein that are nanometers (10^-9) Living or non living? Examples?

Introduction to Viruses Viral structure Viruses are made of nucleic acid (DNA or RNA) and a protein coat called a capsid Some viruses have an envelope and extra spike proteins Viral Life Cycle Viruses must attach and enter host cells They then hijack the host cell’s machinery to complete DNA or RNA replication and protein synthesis New viral particles are created, and are released from the cell

HIV Structure

HIV Viral Life Cycle

Lytic and Lysogenic Life Cycles Viruses have two options for life cycles which result in very different implications for cell function 1. Lytic Cycle- New viral particles are made and released from the cell. Cell lysis causes cell to die 2. Lysogenic- Viral particles enter the cell and insert their genome into the cell where it incorporates into the host genome. No new viral particles are made ….. Yet Only done by some viruses Usually studied in a special kind of virus: bacteriophage Bacteriophage are viruses that infect bacteria

Lytic and Lysogenic Cycles

Viruses and Cancer

Are viruses only bad? Brainstorm two ways we can use viruses for good use Think about why we are learning about them in our biotechnology unit

Gene Therapy Gene Therapy is a field that attempts to use viruses to treat various disorders The general idea is to use viruses to introduce a gene into a cell that would incorporate into the genome and begin making or blocking proteins

What characteristics would you need in a virus to use for gene therapy?

What characteristics would you need in a virus to use for gene therapy? Non-pathogenic Integrates into genome Easy to administer Sequenced genome/know a lot about it Large genome to carry big enough genes

Current Gene Therapy Research

Bacteriophages Bacteriophages are viruses that infect bacteria How can we use these to help humans?

Bacteriophages Bacteriophage are viruses that infect bacteria How can we use these to help humans? Use bacteriophages to deliver toxic effects to bacteria as an alternative to antibiotics Remember antibiotic resistance!

Bacteriophage Therapy How would bacteriophage be a better treatment for bacterial infections than antibiotics?

Bacteriophage vs. Antibiotics

Current Status of Bacteriophage Therapy

Introduction to Bacteria Bacteria are prokaryotic, unicellular organisms

Horizontal Gene Transfer Bacteria can transfer genetic material to each other and members of separate species through horizontal gene transfer 1. Conjugation- genetic material on plasmids is transmitted to another bacteria cell. The plasmids often contain resistant or pathogenic genes 2. Transformation- ‘Naked’ DNA is taken up from the environment and incorporated into the bacteria genome 3. Transduction- DNA is transfer to a bacteria cell through a bacteriophage

Horizontal Gene Transfer (HGT)

HGT Risks for Humans Conjugation frequently spreads antibiotic resistant genes to other cells or species Transformation and transduction can increase the pathogenicity of the bacteria

HGT and Humans How can we exploit HGT to our advantage?

Recombinant DNA Using genetic tools, we can insert genes of interest into bacteria and collect the proteins they make Why would it be advantageous to use bacteria cells for this?

Recombinant DNA and Insulin Also used for..

Future Research for Viruses and Bacteria Gene therapy: More clinical trials Bacteriophage treatment: Determine side effects, effectiveness, reaction to resistant mutations Bacteria Antibiotic resistance: Block HGT (?), More details about normal flora and immune response Genetic engineering: More products (already a pretty solid procedure)