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Bacteria

Bacteria. Kingdoms Eubacteria & Archaebacteria. Bacteria. Single-celled prokaryotes Two kingdoms of bacteria : Archaebacteria Eubacteria. Archaebacteria. Methanogens: Anaerobic bacteria (oxygen is a poison) Produce energy by converting H 2 & CO 2 into methane gas.

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Bacteria

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  1. Bacteria Kingdoms Eubacteria & Archaebacteria

  2. Bacteria Single-celled prokaryotes Two kingdoms of bacteria: • Archaebacteria • Eubacteria

  3. Archaebacteria • Methanogens: Anaerobic bacteria (oxygen is a poison) Produce energy by converting H2 & CO2 into methane gas. • Extreme Halophiles: “Salt-loving" bacteria that use salt to generate ATP for energy. • Thermoacidophiles: Live in extremely acidic environments (pH less than 2) that have extremely high temperatures (up to 110o C). e.g. geothermal springs at Yellowstone National Park.

  4. Archaebacteria

  5. Eubacteria • Contains the bacteria commonly referred to as germs. • This kingdom contains most of the world's bacteria Eubacteria are classified by: • Shape • Clustering • Respiration

  6. Eubacteria Shape • Coccus - round • Bacillus - rod-shaped • Spirillum - spiral-shaped

  7. Eubacteria Clustering • Diplo - a prefix used with the shape name to indicate pairing of cells. • Strepto - a prefix used with the shape name to indicate chains. • Staphylo - a prefix used with the shape name to indicate clusters

  8. Streptococcal (Group A) Infections

  9. Susceptibility & Resistance

  10. Eubacteria Respiration • Obligate anaerobes - cannot survive in the presence of atmospheric oxygen. • Facultative anaerobes - can live with or without atmospheric oxygen. • Obligate aerobes - cannot survive without atmospheric oxygen. MRSA Staphylococcus aureus

  11. The acronym MRSA stands for methicillin-resistant Staphylococcus aureus

  12. Gangrene

  13. Tetanus

  14. Necrotizing Fasciitis

  15. Leprosy

  16. Helicobacter pylori

  17. Lyme Disease

  18. Many antibiotics have no effect on gram-negative bacteria Gram Staining

  19. Parts of a bacteria cell • Cell wall - some rigid and others flexible. • Cell membrane - same as other cells. • Cytoplasm - same as other cells. • DNA - a single, circular chromosome (Plasmid) located in the cytoplasm. Bacteria do not have a nucleus. • Capsule - a thick, gel-like, protective coating on some bacteria cells. • Pili - short, hairlike protein structures on the surface of some bacteria that help them stick to host cells. • Flagella - long protein structures that turn to propel some bacteria cells.

  20. Reproduction • Asexual, by binary fission - the DNA replicates and then the cell pinches inward and splits in two. • Conjugation - two cells exchange a portion of their DNA across a bridge formed between the cells. New material replaces old material in the cell. While this increases the genetic variability in the organisms, it is not true sexual reproduction. • Endospores - during adverse conditions, the DNA is encased in a protective envelope. This endospore can lie dormant for years or until favorable conditions return.

  21. Binary Fission

  22. Conjugation

  23. Toxins Substances that disrupts the metabolism of other organisms. • Endotoxin - made up of lipids and carbohydrates associated with the outer membrane of gram-negative bacteria. These toxins are some of the strongest poisons known to man and cause violent reactions in host organisms. • Exotoxin - proteins produced inside gram-positive bacteria cells and secreted into the environment. These toxins usually produce fever, weakness, and capillary damage.

  24. Antibiotics Drugs that fight bacteria by interfering with their cellular functions. • PENICILLIN interferes with cell wall synthesis. • TETRACYCLINE interferes with protein synthesis. • Many antibiotics are derived from chemicals that bacteria or fungi produce. • SULFA DRUGS - antibiotics that are synthesized in laboratories • Many Antibiotics are able to affect a wide variety of organisms; they are called BROAD SPECTRUM ANTIBIOTICS.

  25. Antibiotic Resistance When a population of bacteria is exposed to an Antibiotic, the most susceptible DIE.  A Few Mutant bacteria that are resistant to the Antibiotic may continue to grow. A Resistant Population then grows from these Mutant Bacteria through reproduction and genetic recombination. These new Population are Antibiotic-Resistant.  This has resulted from the Over Use of Antibiotics.  Many diseases that were once easy to treat are becoming more difficult to treat.

  26. USEFUL BACTERIA • Used in Sewage Treatment, and as Decomposers, breaking down the remains of organic matter in dead plant and animal waste.  Recyclers, returning nutrients back to the environment. • Food production.  Bacteria help us make buttermilk, sour cream, yogurt, cottage cheese, sauerkraut and pickles. • Used in industrial chemical production.  They produce organic chemicals and fuels. They’re used in the mining of minerals and their products are used as insecticides. • Used to help clean up environmental disasters caused by humans, such as chemical and oil spills.

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