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Picture from http://www.buildinggreentv.com/node/7088 http://steveaoki.dimmak.com/blog/2009/11/useless-information-4-bacteria/ http://www.scienceclarified.com/As-Bi/Bacteria.html
Cells need energy (ATP)Cells need energy (ATP)-ATP -Electrons used for ATP synthesis transferred to the molecule(=_______________________)-Terminal electron acceptors(TEA) eg. O2 for aerobes We, humans are aerobic organisms.
Classified by energy (ATP) sourceClassified by energy (ATP) source
•PhototrophsPhototrophs -ATP from ________ -serve as food sources for other organisms. -Aquatic, lakes, bogs, upper layer of muds -Photosynthetic organisms Anoxygenic don’t generate O2 e.g. purple bacteria, green bacteria Oxygenic generate O2 e.g. plants, algae, cyanobacteria,
•Lithotrophs Lithotrophs = Chemolithotrophs - Some use inorganic molecules (lithotrophs) eg. H2
- Anaerobic environments eg. GI tract in human -TEA: CO2 or Sulfur(S) - Most Archea living in hydrothermal vent, Aquatic bacteria.-Methanogens (energy from H2,CO2 as TEA)
Picture from http://io.uwinnipeg.ca/~simmons/16cm05/1116/27-01-HeatLovingProkaryotes.jpg
•AutotrophsAutotrophs - Carbon source from ______. - make sugar (organic compound)
•Heterotrophs(organotrophs)Heterotrophs(organotrophs) - Carbon source organic molecules(sugar or glucose) from ____________. - produce inorganic molecules e.g. CO2
CO2
autotrophs
http://phobia.itqb.unl.pt/grfx/biofilm-image.jpg
Methanogens - A group of archaea - Anaerobic chemolithotrophs - ATP from H2
- TEA: CO2
- may live a/w fermenters fermenter produce H2, CO2 - produce methane and water - sewage, intestinal tracts, etc. - Hard to culture in the lab. - Future energy source for human.
- Sulfur cycle - Rotten-egg small since H2S is generated. - live in anaerobic soils - Produce H2S turn mud and water black. - Most mesophiles or thermophiles
FermentersFermenters-Clostridium obligate anaerobes endospores (dormant form) vegetative cells live in anaerobic conditons created by aerobes. ferment cellulose, sugar, ethanol foul-smell
-Lactic acid bacteria obligate fermenters. *can live in O2 presence. But not use O2
produce lactic acid normal flora; live in mouth,throat, vigina, GI tract
Purple bacteria~Anoxygenic phototrophsPurple bacteria~Anoxygenic phototrophs-Photosynthetic pigments within cell membranecell membrane
-Gram negative-Most aquatic habitats-Electron source from H2S or organic compounds.- do not use electron source from water do not produce oxygen
-Purple sulfur bacteriaPurple sulfur bacteria live in sulfur spring Energy from H2S, H2, organic(pyruvate) gas vesicles(sulfur granules) sulfur oxidizer!
-Purple non-sulfur bacteriaPurple non-sulfur bacteria live a variety of aquatic habitats, moist soils, paddy fields… lack gas vesicles organic molecules as source of electrons or other diverse metabolismPicture from http://starcentral.mbl.edu/microscope/portal.php?pagetitle=assetfactsheet&imageid=12327 http://climatechange.thinkaboutit.eu/think2/post/climate_change_by_pre-
Green bacteria~Anoxygenic phototrophsGreen bacteria~Anoxygenic phototrophs-Photosynthetic pigments within chlorosomes-Gram negative-harder to observe
-Green sulfur bacteriaGreen sulfur bacteria Electron source from H2S,( H2S S ) All strict anaerobes gas vesicels(sulfur granules) sulfur oxidizer!
None is chemotrophs •Green non-sulfur bacteriaGreen non-sulfur bacteria diverse metabolism; alternative use H2 or H2S All strict anaerobes gas vesicels None is chemotrophs; organic molecules as source of electrons. Grow in the dark aerobically using chemotrophic metabolism. Only Chloroflexus can be grown in pure culture.Picture from http://talesfromechocanyon.blogspot.com/2008/06/romvets-tackle-west-thumb-geyser-basin_16.html