Prokaryotic life

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Prokaryotic life
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Prokaryotes

• The smallest and most common microorganisms that
  lack a nucleus.
• Divided into 2 kingdoms Archeabacteria and
  Eubacteria

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Classifying Prokaryotes

• E. coli, a Typical Eubacterium

Ribosomes
Cell Membrane
Cell Wall
Peptidoglycan
Flagellum
Pili
DNA
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Archaebacteria vs. Eubacteria

• Archaebacteria
• Are ancient.
• Lack peptidoglycan.
• Live mostly in harsh environments
• Salty lakes
• Thick mud
• Deep ocean vents
• Guts of animals

• Eubacteria
• Considered true bacteria
• Have peptidoglycan.
• Live almost everywhere.

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Food
Deep Ocean Vent
Eubacteria
Compost
Archaebacteria
Hot Spring Pool _at_ Yellowstone
Cavities
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Characteristics of Bacteria

• Small
• few micrometers in length
• Unicellular
• Found Everywhere
• Many Cause Disease
• Many are Useful
• May have flagella or cilia
• for movement

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Characteristics Continued

• Have a cell wall
• May contain peptidoglycan (a sugar protein
  polymer)
• Can be classified by shape
• Cocci- round
• Bacilli- rod shaped
• Spirilla- spiral

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3 Possible Shapes of Bacteria
Cocci
Bacilli
Spirilla
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• Prefixes Used to Describe Identify Bacteria
• Diplo 2
• Neisseria meningitidis
• (aka diplococcus meningitidis)
• Strepto chain
• Streptococcus pneumonia
• Staphylo clumps
• Ex Staphylococcus aureus

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Identification Continued

• Gram Staining - used to identify bacteria with
  extra membranes
• Extra membrane helps them to better resist
  damage.
• Gram stain purple (have peptidoglycan)
• Gram (extra membrane) stain red

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Characteristics Continued

• Prokayotes can be autotrophs or heterotrophs
• Autotrophs
• Self producers, by sunlight or organic chemicals
• Heterotrophs
• Consumes energy from other organisms
• Energy can be released by
• cellular respiration if there is oxygen available
  
• fermentation if there is no oxygen.

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Bacterial Reproduction

• They can reproduce in 2 main ways
• Binary Fission (asexual) splitting in half
• Conjugation (sexual) sharing genetic info

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Binary Fission
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• Conjugation (sexual) swapping genes over a
  bridge between two bacteria

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Importance of Bacteria

• Decomposers
• Nitrogen Fixation
• Photosynthesis (oxygen)
• Oil spill clean up
• Digestion aid vitamin production
• Foods such as cheese and yogurt
• Medicines

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Importance of Bacteria Continued

• Symbiotic relationship (Mutualism)
• - E. coli in the intestines aid in digestion
  and produce vitamins in exchange for food and
  a warm home.

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Biowarfare

• Bacillus anthracis
• Commonly known as anthrax
• Lives in the soil
• Forms spore
• Can be fatal
• A number of bacteria cause disease, these are
  called pathogens.

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Careers with Bacteria

• Microbiologist - studies and cultures bacteria
• Epidemiologist -Study infectious diseases and how
  they spread.
• Food Safety Inspector- check slaughtered animal
  carcasses for disease or bacteria

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Evolution of Bacteria

• Recall All living organisms have evolved from a
  common ancestor.
• Modern research uses bacteria as a model to
• study evolution because they are diverse and
  divide
• rapidly.
• Bacteria can evolve quickly to a changing
  environment.

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Evolution of antibiotic resistant bacteria

Bacteria can share genetic content, which is a
way of sexual reproduction. This is why bacteria
are so successful the sharing of advantageous
properties may enable evolving species to become
even more successful.
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• Their success depends on the selective pressures
  that are applied.
• The 'emergence' of antibiotic resistant bacteria
  is evolution.
• Two mechanisms are responsible for the spread of
  antibiotic resistance among bacteria 1)
  mutations can arise that result in resistance to
  anti-biotics and 2) some bacteria simply steal
  the DNA of their counterparts that have learned
  to deal with antibiotics.

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Why so successful in evolving?

• Short, rapid reproduction time
• Diversity of bacteria Bacteria can be found
  virtually everywhere. They are in the air, soil,
  water, and in and on plants and animals,
  including us.

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Other examples of bacterial evolution

• Bacterial resistance to anti-biotics
• Bacterial resistance to anti-microbials (hand
  sanitizer/soap)