Bacteria - Eubacteria

Domain Prokarya

Shifting Kingdoms2 3 5 6 8

Bacteria Bacteria Bacteria Bacteria Bacteria

Archaebacteria

ArchaebacteriaArchaebacteri

aArchaebacteri

aArchaebacter

ia

Archezoans Archezoans Archezoans Archezoans Archezoans

Euglenoids Euglenoids Euglenoids Euglenoids Euglenoids

Chrysophytes Chrysophytes Chrysophytes Chrysophytes Chrysophytes

Green Algae Green Algae Green Algae Green Algae Green Algae

Brown Algae Brown Algae Brown Algae Brown Algae Brown Algae

Red algae Red algae Red algae Red algae Red algae

Slime Molds Slime Molds Slime Molds Slime Molds Slime Molds

True Fungi True Fungi True Fungi True Fungi True Fungi

Bryophytes Bryophytes Bryophytes Bryophytes Bryophytes

Tracheophytes Tracheophytes Tracheophytes TracheophytesTracheophyte

s

Protozoans Protozoans Protozoans Protozoans Protozoans

Myxozoans Myxozoans Myxozoans Myxozoans Myxozoans

Multicellular Animals

Multicellular Animals

Multicellular Animals

Multicellular Animals

Multicellular Animals

Lumpers Splitters

PlantaeMoneraBacteria-Eubacteria

How Many Kingdoms?Multicellul

ar Animals

Myxozoans

Protozoans

Tracheophytes

Bryophytes

True Fungi

Slime Molds

Red algae

Brown Algae

Green Algae

Chrysophytes

Euglenoids

Archezoans

Archaebacteria

Bacteria

Original Cell

Extant

Extinct

Long Time with

Prokaryotes only

8

5

3

2

1

Bacteria - Eubacteria• Ancient fossils 3.5 billion years b.p.• Archetype for prokaryotic organisms

– Phototrophs– Chemoautotrophs– Heterotrophs– Saprobes– Parasites (bacteria benefit, host harmed)– Commensals (bacteria benefit, host unharmed)

– Mutualists (bacteria and host both benefit)

• Unicellular, colonial, filamentous• Bacillus, coccus, spirillum

Cell SizesMycoplasma 0.3-0.8 µm

E. coli 1x2 µm

Cyanobacteria 10 µm diam

Plant Cell 30x75 µm

Obviously eukaryoticNucleus presentMitochondrion BacteriumChloroplast Cyanobacterium

Cell ShapesCoccus - cocci

Bacillus - bacillus

Spirillum - spirilli

Vibrio - vibrios

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http://www.up.ac.za/academic/electron/bacteria.jpg

http://phil.cdc.gov/PHIL_Images/02142002/00001/PHIL_138.tif

Leptospira

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http://www.designthatmatters.org/proto_portfolio/cholera_treatment/multimedia/vibrio_cholerae.jpg

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http://helico.gsnu.ac.kr/

Vibrio cholerae

Helicobacter pylori

Cell Associations

Coccus

Diplococcus

Streptococcus - filamentous

Staphylococcus - colonial

? Streptobacillus

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http://www.hhs.gov/asphep/presentation/images/bacteria.jpg

Cell Structure: Boundary

Gram Positive Gram Negative

Mycoplasma

cell membrane bilayer lipopolysaccharide transport proteins

cell wall-murein peptidoglycan muramic acid - peptide

additional membrane bilayer lipopolysaccharide

cytosol

regulates input/output

prevents burstingturgor pressurepenicillin sensitive

releases dye

Capsule or Sheath

Cell Structure: Boundary Defenses

cell adhesionchemical resistance - defensedesiccation resistance

mucoid polysaccharides

spore coat + DNA + other materials

exterior may be lostfrozen for long periodsboiled for long periodsdesiccated for long periodsthen germinates to new cell

Endospore

Bacillus anthracis

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http://library.thinkquest.org/3564/Cells/cell91.gif

?

?

Cell Structure: Movement

anchoragerotation

basal rings

and rod

stiff helical flagellum

is rotated by “motor apparatus”in the membrane by H+ ATPaseat rates of 200-1700 rps (>12,000 rpm!)

hookdirectional rotation?

flagellin protein

Exceptions:myxomycetes, some cyanobacteria use slime, but how?spirochetes have flexible internal microtubules (endosymbiotic source of flagella in eukaryotes?) ((gut parasite in termites have spirochete symbiosis))

Taxis: movement toward stimulus

phototaxis: movement toward light

chemotaxis: movement to chemicals

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http://msucares.com/lawn/tree_diseases/images/bacteria.gif

Lophotrichous: flagella found at one end of the cell

http://www.biophysics.uwa.edu.au/STAWA/scans/40545a.jpg

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http://www.biophysics.uwa.edu.au/STAWA/scans/40540a.jpg

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Amphitrichous: flagella at both ends (but not many on sides)

Peritrichous: flagella all around cell

Prokaryotic Growth• Cells are generally very small• Cells may double in size but only before binary fission

• Growth mostly in terms of cell number or colony size, etc.

• Doubling time in cell numbers may be 20 minutes in ideal conditions

• Could quickly take over the earth if conditions could remain ideal

• Very competitive in ideal environments

• Ultimate survivors - 3.5 billion years!

Cell Structure: Nucleoid

transcription by RNA polymerase

one circular DNA moleculeno histone protein associationattached to cell membrane

separation of chromosomes

replication by DNA polymerase

Nucleoid - genome

translation of mRNA into protein

rRNA + protein + ribozymes

70S Ribosome

cytokinesis by furrowing

Process called binary fission NOT mitosis!

•Genome and copy are identical•Genome is haploid•There is no synapsis•There is no recombination

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http://www.nature.com/news/2002/020722/full/020722-11.html

nucleoids

initial furrowing

furrowing complete