Martinus Beijerinck

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Martinus Beijerinck
discovered many bacterial species including
azotobacter, which is a free-living organism able
to fix N2 from air. Also worked with rhizobia,
symbiotic N2 fixers. Also photobacterium (light
emitting) sulfate reducers, methane producers,..
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Ecology Balance between biosynthesis and
biodegradation
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Sergei Winogradsky .. discovered the concept
of autotrophy, i.e. converting H2S to H2 S as
energy source, and fixing CO2 as carbon source
(like plants) via the Calvin cycle he
also isolated Clostridium pasteurianum as a N2
fixing anaerobe
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Hyperthermophiles/Barophiles
Black smoker
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Nutritional Factors that Influence Microbial
Growth Hydrothermal vent community the
diverse community of life is supported by the
metabolic activities of chemolithoautotrophs
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Tubeworm-symbionts - they are chemolithoautotrophs
providing the tubeworm which is
chemoorganoheterotroph with a carbon and energy
source
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Extremophiles a. Thermophiles (Thomas Brock)
e.g. isolation of Taq polymerase from Thermus
aquaticus Obsidian Pool, Yellowstone
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Extremophiles b. Hyperthermophiles/Acidophiles
(Karl Stetter)
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Halophiles
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Radiation-Resistant Microrganism Deinococcus
Radiodurans Adaptation to high radiation high
number of DNA repair enzymes