Transcript Archaebacteria

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One out of the two kingdoms of bacteria
› Unicellular prokaryotes
› Ancestors of eukaryotic cells
Emerged over 3.5 billion years ago
 First discovered in 1977
 Represented today by a
few groups of bacteria
inhabiting extreme
environments
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Archaebacteria are quite different from
eukaryotes
› They don’t possess membrane-bound
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organelles
They have a thick cytoplasm
Lack Peptidoglycan
They produce protein from their DNA
Their genes have introns
Have unique lipids in plasma membranes
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Asexual Reproduction
› Binary Fission
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Genetic material can be exchanged
between cells by three different
proccesses
› Transformation
› Transduction
› Conjugation
1/10th of a micrometer- 15 micro meters
 Can withstand pressures of above 200
atmospheres
 Non-pathogenic
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› They can live in and around other organisms
but not infecting them
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Make up the largest
group of
Archaebacteria
known of so far
Usually coccoid
(spherical) or bacilli
(rod shaped)
Strictly anaerobic
› Poisoned and killed
by traces of oxygen
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Convert CO2 into
Methane
› Release 2 trillion kg of
methane gas per year
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The large quantities
of methane
influence carbon
dioxide levels in the
atmosphere
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Evolved before there was oxygen in the
atmosphere
› Developed new ways of producing energy
without oxygen present
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Instead of photosynthesis, they combine
Hydrogen, (H2), with Carbon Monoxide,
(CO2), to form Methane, (CH4)
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Could have lived anywhere in ancient times
Today, they live only where no oxygen is present
and hydrogen and carbon dioxide are available
› Sewage treatment plants, stagnant water, hot springs,
and bottom of the ocean
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Common in wetlands
› Responsible for marsh gas, CH4
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Found in intestinal tracts of ruminant and humans
› Responsible for belching and flatulence
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Lives best in relatively
high temperatures
› 45-80oC, 113-176oF
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Found in geothermal
heated regions of
the Earth
› Yellowstone
National Park, deep
sea hydrothermal
vents, and
decaying plant
matter
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Obligate Thermophiles (Extreme
Thermophiles)
› Require high temperatures for growth, 50-80oC
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Facultative Thermophiles (Moderate
Thermophiles)
› Thrive at high and low temperatures, 40-70oC
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Hyperthermophiles
› Optimal temperatures are 80o-105oC
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Anaerobic
Live in extreme environments
› Thrive in acidic, rich in sulfur, and high
temperature areas
› Can tolerate temperatures up to 70-90o C
› Acid levels- pH 2 to 3
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The plasma membrane contains high
amounts of saturated fats
Its enzymes are able to withstand extreme
conditions without denaturation
› a structural change in macromolecules caused by
extreme conditions
Halophile means “salt loving”
 Aerobic microorganisms
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› Create ATP by aerobic pathways
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Most can perform a special type of
photosynthesis without chlorophyll
› Can also use the high concentrations of salt
to help produce energy
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Can live in high concentrates of salt
› 10 times the amount of salt content of
normal ocean water
› Great Salt Lake, Utah, Owens Lake, Calf.
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Optimal growth occurs at 20-25% salt
solution
› Can continue to grow in solutions up to 37%
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Use osmotic pressure and chemical
substances to control the amount of salt
inside the cell
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Coated with a special protein covering
› Used to allow only certain levels of salt into
the cell.
This covering helps to seal in water with
the right level of salt
 Uses diffusion to help keep the salt
content at the right level
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Halophiles have
turned the land
surrounding the
Great Salt Lake a
reddish color
› This happens after
flood water spreads
onto the land
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Tinted red by salt-loving bacteria
15-30% salinity
http://en.wikipedia.org/wiki/Methanoge
n
 http://library.thinkquest.org/CR0212089/h
alo.htm
 http://www.angelfire.com/ks3/cmondra
gon/Archaebacteria.html
 http://zipcodezoo.com/Key/Archaea/ar
chaea_kingdom.asp
 http://users.rcn.com/jkimball.ma.ultranet
/BiologyPages/A/Archaea.html
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http://en.wikipedia.org/wiki/Thermoacid
ophile
 http://en.wikipedia.org/wiki/Halophile
 http://www.sparknotes.com/biology/mic
roorganisms/monera/section2.rhtml
 http://www.daviddarling.info/encyclope
dia/M/methanogen.html
 http://www.buzzle.com/articles/charact
eristics-of-archaebacteria.html
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