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Ch 17: Prokaryotes: Bacteria & Archaea

(Images not from our textbook are from the Internet -> use a search engine & retrieve by name as an “Images” rather than text)

Prokaryotic cell (from Wikipedia)

Fimbriae/

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Bacterial conjugation: moving DNA to another cell

Folded “extra” plasma membrane

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Endospore = Spore

only a few bacteria can make these

bacilli

cocci

spirals & vibrios

Most common shapes

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Most common reproduction - binary fission

copy chromosome (DNA)

continue to grow until big enough to split

Organism Nutrition

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Organism Nutrition

Organism Nutrition

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Domain Bacteria = Kingdom Bacteria

early step in identification

peptidoglycan in cell walls

a lot = Gram +

a little = Gram -

Gram- P: Proteobacteria: chemoheterotrophic animal gut inhabitants

Escherichia coli

Salmonella Yersinia

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more P: Proteobacteria: chemoheterotrophic symbiotic nitrogen-fixers

Rhizobium

root nodules

(tip of a root hair)

more P: Proteobacteria: photosynthesizers

Purple non-sulfur bacteria

(photoheterotrophic) eg: Rhodospirillum

Purple sulfur bacteria

(photoautotrophic)

eg: Chromatium

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more P: Proteobacteria: chemoheterotrophic plant pathogens

Agrobacterium

Other examples:

Pseudomonas syringae, P. cepacia (some other pseudomonads are not plant pathogens)

causes “crown gall”

more P: Proteobacteria: other human pathogens

Legionella (Legionnaire’s disease)

Francisella (Tule fever)

Neisseria

- gonorrhea, - meningitis

Rickettsia (Rocky Mountain Spotted Fever)

(brucellosis)

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more P: Proteobacteria: other chemoheterotrophs Spirillum

Vibrio Flashlight fish (with bioluminescent Vibrio)

And a few chemoautotrophs: Nitrobacter Nitrosomonas

Gram -

P: Chloroflexi = green non-sulfur bacteria

(photoheterotrophs)

eg: Chloroflexus

Gram -

P: Chlorobi = green sulfur bacteria

(photoautotrophs)

eg: Chlorobium

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Gram - P: Cyanobacteria

photoautotrophs Anabaena

heterocyst

phycocyanin phycoerythrin

Anabaena fern

Accessory pigments

“green manure” symbiosis

N fixation

more P: Cyanobacteria

Spirulina

Prochloron

symbiosis with tunicates

Nostoc

Prochlorococcus Synechococcus

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more P: Cyanobacteria

Lyngbya

Trichodesmium Oscillatoria

sheath

toxic

† Microcystis

Gram- P: Spirochaetes human pathogen examples Borrelia burgdorferi

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Gram- P: Chlamydiae human pathogen examples

Gram + P: Actinobacteria chemoheterotophs

Streptomyces

Frankia N fixation

Brevibacterium

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Bacillus

B. anthracis (mammal pathogen)

B. thuringensis, B. popilliae (makes natural insecticide)

Gram + P: Firmicutes

more P: Firmicutes

Clostridium tetani

Clostridium perfringens

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Lactobacillus

more P: Firmicutes Mycoplasma

Staphylococcus Streptococcus

Domain Archaea = Kingdom Archaea = archaebacteria (older)

pseudomurein cell walls (instead of peptidoglycan)

extremophile examples:

methane-producers, temperature, salt, acid

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Thermoplasma

P: Euryarcheota

Methanobacterium Halobacterium

Pyrodictium

P: Crenarcheota Sulfolobus

Thermoproteus

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Known only from environmental samples

3-4 known phyla

& Nanoarcheota ?

(at least 1 more phylum is being discussed)

In 2015, a surprise