Bacteria continued'''

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Bacteria continued...
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Types of Archaebacteria

• Methanogens
• Harvests energy by converting H2 and CO2 to
  methane (O2 is poisonous to them)
• Live in anaerobic environments (swamps, sewage,
  intestines)

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Types of Archaebacteria cont

• Extreme halophiles
• Salt-loving
• Use the salt to generate ATP
• Found in places like the Great Salt Lake and the
  Dead Sea

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Types of Archaebacteria cont

• Thermacidophiles
• Live in extremely acidic environments and high
  temperatures
• Temps up to 102o and pH less than 2
• Found in hot springs, near volcanic vents, and
  cracks in the ocean floor

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V. Bacterial types

• A. Coccus (pl. - cocci) - round

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B. Bacillus (pl. - bacilli) - rod-shaped Ex. -
E. coli
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C. Spirillum (pl. - spirilla) - spiral
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D. Diplo- (prefix meaning 2)

• diplococcus
• diplobacillus
• E. Strepto- (prefix meaning chains)
• streptococcus
• streptobacillus
• F. Staphlo- (prefix meaning clusters)
• staphlococcus

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Tuberculosis bacillus
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Staph infection
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Streptococcus A

• Flesh eating bacteria

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Some Phyla of Eubacteria
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VI. Nutrition Growth

• A. Autotrophic - obtain energy from light or
  minerals
• photoautotrophs - use light-trapping compounds
• chemoautotrophs - use compounds like ammonia
• B. Heterotrophic - use organic matter for energy
  

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C. O2 requirements

• obligate anaerobes
• cannot survive in O2
• ex. Clostridium tetanus
• facultative anaerobes
• live with or w/out O2
• ex. E. coli
• obligate aerobes
• cannot survive w/out O2
• ex. Mycobacterium tuberculosis

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Mycobacterium
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D. optimum temp.

• most grow best at 68ºF - 104ºF
• thermophilic bacteria grow best at 104º- 230ºF
• E. Optimum pH - 6.5 -7.5

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Thermophilic bacteria
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Bacteria and Disease

• Pathology
• Scientific study of disease
• Bacteria cause disease by producing toxins
• Exotoxins-made of protein produced by
  Gram-positive bacteria secreted into environment
• Ex Tetanus

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Bacteria and Disease Cont

• Endotoxins- made of lipids and carbs produced by
  Gram-negative bacteria not released until
  bacteria die
• Cause fever, body aches, weakness, damage vessels
  in circulatory system
• Can also cause disease by destroying body tissue
• Attach to host and secrete digestive enzymes
• Ex some Streptococci bacteria

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Antibiotics

• Drugs that combat with bacteria by interfering
  with various cellular functions
• Examples
• Penicillin- interferes with cell wall synthesis
• Tetracycline- interferes with protein synthesis
• Sulfa drugs- man-made interferes with cell
  metabolism

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Useful Bacteria

• Break down remains of organic matter in plant and
  animal waste in sewage treatment
• Producing and processing food
• Ex Ferment lactose in milk to produce
  buttermilk, yogurt, and sour cream
• Produce sauerkraut and pickles
• Used in industrial chemical production
• Ex petroleum recovery, insecticides

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VII. 3 ways of genetic recombination

• A. Transformation
• bacterium takes in DNA from external environment
• new DNA is substituted for DNA fragment in
  bacterial chromosome

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• B. Conjugation
• 2 bacteria join together to exchange genetic
  material
• bacterium w/ a specialized pilus plasmid forms
  a conjugation bridge w/ bacterium w/out pilus
  plasmid
• plasmid passes through bridge to acceptor
  bacterium

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Conjugatingbacteria
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RECOMBINATION CONTD

• C. Transduction
• virus obtains DNA fragment from host bacterium
• when viruses replicate, they make copies of host
  DNA
• new viruses carry host DNA to a new bacterium
  which expresses it