1. Microbial Biotechnology Chapter 5

2. The Structure of Microbes zProkaryotes Archaebacteria Includes halophiles, thermophiles, “extremophiles” Eubacteria On skin, soil, water, can be pathogenic

3. The Structure of Microbes zCharacteristics of Prokaryotes Generally smaller than Eukaryotes No nucleus Cell wall composed of peptidoglycan Conjugation (transfer of DNA by cytoplasmic bridge) Transduction (DNA is packaged in a virus and infects recipient bacterial cells) 20 minute growth rate (binary fission

4. Yeast are Important Too! zSingle celled eukaryote zKingdom: Fungi zOver 1.5 million species zSource of antibiotics, blood cholesterol lowering drugs zAble to do post translational modifications zGrow anaerobic or aerobic zExamples: Pichia pastoris (grows to a higher density than most laboratory strains), has a no. of strong promoters, can be used in batch processes

5. Microorganisms as Tools zMicrobial Enzymes Taq (DNA polymerase), cellulases, proteases, amylases

6. zBacterial Transformation The ability of bacteria to take in DNA from their surrounding environment Bacteria must be made competent to take up DNA Microorganisms as Tools

7. zCloning and Expression Techniques Fusion Proteins Microorganisms as Tools

8. zMicrobial Proteins as Reporters Examples: the lux gene which produces luciferase Used to develop a fluorescent bioassay to test for TB Microorganisms as Tools

9. zYeast Two-Hybrid System Used to study protein interactions Microorganisms as Tools

10. Using Microbes for a Variety of Everyday Applications zFood Products Rennin used to make curds (solid) and whey in production of cheese Recombinant rennin is known as chymosin (first recombinant food product approved by FDA)

11. Using Microbes for a Variety of Everyday Applications zFood Products Energy production in bacteria Aerobic or anaerobic

12. Using Microbes for a Variety of Everyday Applications zFood Products Fermentation (anaerobic respiration) Lactic acid fermentation Used to make cheese, yogurt, etc. Ethanol fermentation Used to make beer and wine

13. zTherapeutic proteins Recombinant insulin in bacteria Using Microbes for a Variety of Everyday Applications

14. zField Applications of Recombinant Microorganisms Ice-minus bacteria (remove ice protein producing genes from P. syringae) P. fluorescens containing the gene that codes for the bacterial toxin from Bacillus thuringiensis (kills insects) Bt toxin! Using Microbes for a Variety of Everyday Applications

15. zUsing Microbes Against Other Microbes Antibiotics Act in a few key ways Prevent replication Kill directly Damage cell wall or prevent its synthesis Using Microbes for a Variety of Everyday Applications

16. Vaccines zFirst was a vaccine against smallpox (cowpox provides immunity) DPT-diphtheria, pertussis, and tetanus MMR –measles, mumps, and rubella OPV- oral polio vaccine (Sabin)

17. zA Primer on Antibodies Antigen- foreign substances that stimulate an immune response Types of leukocytes or white blood cells B-lymphocytes: antibody-mediated immunity T-lymphocytes: cellular immunity Macrophages: “cell eating” (phagocytosis) Vaccines

18. Heavy chain Light chain IgA – first line of defense IgG and IgM – activates macrophages Vaccines zAntigens stimulate antibody production in the immune system

19. Vaccines zMechanism of Antibody Action

20. zHow are vaccines made? They can be part of a pathogen (e.g. a toxin) or whole organism that is dead or alive but attenuated (doesn’t cause disease) Subunit (toxin) or another part of the pathogen Attenuated (doesn’t cause disease) Inactivated (killed) zWhat about flu vaccines (why do we have to get a shot every year?) Vaccines

21. Bacterial and Viral Targets for Vaccines zImmune Therapy Used to enhance natural immune responses Ex: Interferon is a protein that triggers production of protective proteins (or antibodies) that inhibit viral replication.

22. Bacterial and Viral Targets for Vaccines zHIV

23. Microbial Genomes zMicrobial Genome Program (MGP) –the goal is to sequence the entire genomes of microorganisms that have potential applications in environmental biology, research, industry, and health zSequencing Strategies 

24. Microbial Genomes zWhy study viral genomes? Decipher genes and their products so that agents that block attachment, block replication can be made

25. Microbial Diagnostics zUsing Molecular Techniques to Identify Bacteria RFLP PCR and Real time PCR Sequencing

26. Microbial Diagnostics zMicroarrays for tracking contagious disease PulseNet used to identify outbreaks

27. zCombating Bioterrorism The use of biological materials as weapons to harm humans or animals and plants we depend on for food Examples in History Throwing plague infected dead bodies over the walls of their enemies Microbial Diagnostics

28. zUsing Biotech Against Bioweapons Postal service x-raying packages Antibody tests in the field PCR tests in the field Protein Microarrays for detecting bioweapon pathogens Microbial Diagnostics