VIrophages Viruses that infect other viruses Mamavirus o Greatly reduced amoeba survival and reproduction Amoebas o There were smaller viruses inside the mamavirus and the amoeba s cytoplasm o Smaller icosahedral virions o Reduces mamavirus replication o 3 fold decrease in amoeba death o 70 reduction of mamavirus output o Greatly increased amoeba growth without mamavirus o New virus named Sputnik Prokaryotes Lack a membrane bound nucleus Carl Woesa came up with the different domains Eukarya Bacteria Archaea Bacteria and archaea are prokaryotes Prokaryote fossil o 3 8 billion years ago anoxic environment o Complex lipids found in modern bacteria present in fossils o Evidence for carbon fixation Inorganic carbon organic carbon Prokaryotes are the most abundant life forms on Earth Living systems would collapse without them Bacteria and Archaea Very simple organisms morphologically o Bacillus rod shaped o Coccus round oval coccoid o Spirillum spiral helical Can form filaments o Examples coccoid bacteria linked together Bacillus bacteria linked together Because they are so simple morphologically o led to the use of biochemical genetic comparisons to determine prokaryote diversity 3 differences between Archaea and Bacteria 1 Structure of cell plasma membrane differs a Bacteria have ester bonds in their membranes b Archaea have ether bonds in their membranes This has a huge impact on where you find them i ii Ether bonds are much more stable than ester bonds tough to break down 2 Cell wall structure differs a Bacteria have peptidoglycan as their major structural component b Archaea have no peptidoglycan 3 Genetic machinery associated with protein synthesis production differs a Archaea have the same system as Eukarya i They use introns and exons ii Alter the pattern of gene expression which results in differences in protein produced iii Lots of protein diversity b Bacteria have a unique simpler system i Lack introns and exons ii Decreased protein diversity Archaea Found everywhere No parasites or pathogens in this group Many are found in normal environmental conditions Extremophiles o Lovers of extreme conditions o Some symbiotes Commensalists 0 Mutualists 1 Thermophiles 60 80 degrees Celsius a Hot springs deep sea thermal vents b Have heat stable enzymes c Deep sea vents i Loaded with hydrogen sulfide H2S ii Archaea metabolize H2S for their energy needs d Thermus aquaticus i Only in Yellowstone National Park ii Produces heat stable enzyme Taq polymerase iii Taq used in PCR polymerase chain reactions Takes a single piece of DNA and amplify it into thousands millions of copies e Hypothermophile i Pyrococcus furiosus ii Optimal growth temperature 100 degrees Celsius iii Heat stable enzyme has Tungsten which has the highest melting point 2 Acidophiles do well below pH 2 0 a Found in acidic aquatic conditions bogs and terrestrial environment pine forest soils b Acid mine drainage OH PA Wales i Archaea only living thing in them ii Common in yogurt buttermilk sour cream iii Can block proton uptake increases acidity 3 Halophiles a High salinity optimal is 40 salinity still maintain normal osmotic pressure b Great Salt Lake Dead Sea Soy Sauce sauerkraut c Highly saline soils where no plants grow i Take halophile genes that allow increased survival under saline conditions Insert into crop genome ii 4 Methanogens a Produce massive amounts of methane atmospheric greenhouse gas b Wetlands produce a large portion of Earth s methane c Cow intestines are loaded with methanogens d Trash dumps i Burning off methane e Use methane for biogas power sources
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