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Microbiological concepts explained using examples from deep-sea and terrestrial hydrothermal ecosystems. Anna-Louise Reysenbach reysenbacha@pdx.edu, www.alrlab.pdx.edu. Outline. Diversity of microbes Culturing the unculturables-use of 16S rRNA techniques Early evolution of life Astrobiology
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Microbiological concepts explained using examples from deep-sea and terrestrial hydrothermal ecosystems Anna-Louise Reysenbach reysenbacha@pdx.edu, www.alrlab.pdx.edu
Outline • Diversity of microbes • Culturing the unculturables-use of 16S rRNA techniques • Early evolution of life • Astrobiology • Other concepts/topics • Symbioses • Stress responses • Bioprospecting and biotech
BACTERIA ARCHAEA EUKARYA
Proteobacteria Bacteria • Anoxygenic phototrophs • H2S • S0 stored in cell e.g. Chromatium tepedium
Green sulfur bacteria • Anoxygenic phototrophs • H2S • S0 outside the cell, SO42- • Generally tolerates > H2S than purples • Reverse citric cycle • photoheterotrophy Bacteria
Cyanobacteria-oxygenic phototrophs Bacteria
Cyanobacteria and Green non-S bacteria • Anoxygenic phototroph • “Mix between greenS and purple” • Can grow heterotrophically in dark by aerobic respiration • Unique CO2 fixation pathway, hydroxyproprionate pathway
Cyanidium & Dactylaria Eucarya Algae &Fungi pH 1 Lichen-like relationship? Nice eg.-Nymph Creek
New Viruses from Yellowstone Amphitheater Springs 7/99 Rabbit Creek 10/00 Mud Volcano 8/00 G. Rice Rice et al., (2001) P.N.A.S.98/23 13341-5 K.M.S. 12/01
Thermus worldwide distribution subsurface isolates heterotrophs iron reducers mixotrophic S-oxidizer PCR Bacteria
Other thermophilic Bacteria • Plantomycetes • Gram +- Thermoterrabacterium • Spirochetes • Thermotoga • Hugenholtz et al.1998. J BAct Thermotoga Stetter et al
A novel lineage within the Bacteria -sulfur reducers exclusive to deep-sea vents? Desulfurobacteriales-A new order for deep-sea vents? L’Haridon et al. 1998 Jeanthon and Reysenbach, (unpublished)
Aquificales • “knall gas” • microaerophiles • or nitrate • Recently isolated from deep-sea vents Bacteria
Sulfolobus • Crenarchaeote • Obligate aerobe • Some strains oxidize and reduce sulfur • Pyrite oxidizer • Chemolitho and hetero • WHY not at deep-sea vents???
Biogeographicalconsiderations in the Euryarchaeota Thermococcus-cosmopolitan Methanothermus-endemic?
The world record holders: High temperature--- Pyrolobus fumarii discuss mechanisms of thermal stability/ oxygen protection Smallest cells---- Nanoarchaeum (Nature) discuss method of isolation and treeing problems
Korarchaeota • Slightly acidic, pH 6 • Yellowstone,Japan,reports from Kamchatka and New Zealand • No known physiology… • Grown as enrichments Archaea