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Bacteria and Archaea Archaea Bacteria Prokaryotes Are Ubiquitous!

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Bacteria and Archaea Archaea Bacteria Prokaryotes Are Ubiquitous! 2/3/13 Bacteria and Archaea Archaea Bacteria EUKARYA • Origin of Life – RNA World – First cells – LUCA • Bacteria and Archaea ARCHAEA BACTERIA – General characteristics – Cyanobacteria – Gram positive – Genetic Exchange • What’s the difference? FebFeb 4, 4, 2013 2013 Prokaryotes are Ubiquitous! Sequencing the Ocean Morphology Many ways to get energy: • Autotrophs e.g. Cyanobacteria • Heterotrophs e.g. Lactobacillus Streptococcus Staphylococcus 1 2/3/13 Fig. 25-7 Ceno- Meso- zoic zoic Humans Paleozoic Nitrogen cycling Colonization of land Animals Origin of solar system and Earth 1 4 Proterozoic Archaean Prokaryotes Billions of 2 years ago3 Multicellular eukaryotes Single-celled eukaryotes Atmospheric oxygen Filamentous cyanobacteria from the Bitter Springs Chert Cyanobacteria - among the oldest fossils Stromatolite section! Stromatolites: colonies of cyanobacteria! Fig. 25-7 Ceno- Meso- zoic zoic Humans Banded Iron Deposits Paleozoic Colonization of land Animals Origin of solar system and Earth 1 4 Proterozoic Archaean Prokaryotes Billions of 2 years ago3 Multicellular eukaryotes Single-celled eukaryotes Atmospheric oxygen Fig. 25-8 2 2/3/13 Fig. 27-17 Eukarya Domain Archaea Eukaryotes Korarcheotes Archaea Domain Euryarchaeotes Crenarchaeotes UNIVERSAL Nanoarchaeotes ANCESTOR Proteobacteria Domain Bacteria Domain Bacteria Chlamydias Spirochetes Cyanobacteria Gram-positive bacteria Table 27-2 Archaea • methanogens • extreme halophiles • extreme thermophiles • One feature: – different cell membrane Eukarya Domain Bacteria Eukaryotes Gram Positive and Gram Negative Korarcheotes Archaea Domain Carbohydrate portion Euryarchaeotes of lipopolysaccharide Outer Peptidoglycan membrane Cell Cell wall layer wall Peptidoglycan Crenarchaeotes layer Plasma membrane Plasma membrane UNIVERSAL Nanoarchaeotes ANCESTOR Protein Protein Proteobacteria Gram- Gram- Domain Bacteria Domain Bacteria positive negative bacteria bacteria Chlamydias 20 !m (a) Gram-positive: peptidoglycan traps (b) Gram-negative: crystal violet is easily rinsed away, Spirochetes crystal violet. revealing red dye. Cyanobacteria Gram-positive bacteria 3 2/3/13 Fig. 27-18a Fig. 27-18i You do not Subgroup: Alpha Proteobacteria Alpha need to Beta CHLAMYDIAS SPIROCHETES Gamma Proteobacteriamemorize Delta m Epsilon these groups ! 2.5 Rhizobium (arrows) inside a root cell of a legume (TEM) m m Subgroup: Beta Proteobacteria ! Subgroup: Gamma Proteobacteria ! 5 2.5 Chlamydia (arrows) inside an Leptospira, a spirochete animal cell (colorized TEM) (colorized TEM) m m ! ! 1 CYANOBACTERIA GRAM-POSITIVE BACTERIA 0.5 Nitrosomonas (colorized TEM) Thiomargarita namibiensis containing sulfur wastes (LM) Subgroup: Delta Proteobacteria Subgroup: Epsilon Proteobacteria m m m ! ! ! 1 5 50 Hundreds of mycoplasmas B. bacteriophorus Two species of Oscillatoria, Streptomyces, the source of covering a human fibroblast m m filamentous cyanobacteria (LM) many antibiotics (colorized SEM) m ! ! ! cell (colorized SEM) 5 2 10 Fruiting bodies of Bdellovibrio bacteriophorus Helicobacter pylori (colorized TEM) Chondromyces crocatus, a attacking a larger bacterium myxobacterium (SEM) (colorized TEM) EXPERIMENT Daily serial transfer Adaptability Genetic Exchange 0.1 mL (population sample) Old tube New tube (discarded (9.9 mL after growth transfer) medium) • Transformation RESULTS • Transduction 1.8 • Conjugation 1.6 1.4 to ancestor to ancestor Fitness relative Fitness relative 1.2 1.0 0 5,000 10,000 15,000 20,000 Generation Antibiotic Resistance 4 .
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