Bacteria - Eubacteria Domain Prokarya

Multicellular Animals Shifting Kingdoms Lumpers Plantae Monera Bacteria-Eubacteria Splitters 2 3 5 6 8 Bacteria Archaebacteria Archezoans Euglenoids Chrysophytes Green Algae Brown Algae Red algae Slime Molds True Fungi Bryophytes Tracheophytes Protozoans Myxozoans Multicellular Animals

How Many Kingdoms? Extant 8 5 3 Extinct 2 Long Time with 1 Multicellular Animals Myxozoans Protozoans Tracheophytes Bryophytes True Fungi Slime Molds Red algae Brown Algae Green Algae Chrysophytes Euglenoids Archezoans Archaebacteria Bacteria 8 5 3 Extinct 2 1 Long Time with Prokaryotes only Original Cell

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 Sizes Mycoplasma 0.3-0.8 µm E. coli 1x2 µm Cyanobacteria 10 µm diam Plant Cell 30x75 µm Obviously eukaryotic Nucleus present Mitochondrion  Bacterium Chloroplast  Cyanobacterium

Cell Shapes Coccus - cocci Bacillus - bacillus Spirillum - spirilli Vibrio - vibrios

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

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

Vibrio cholerae Helicobacter pylori http://www.designthatmatters.org/proto_portfolio/cholera_treatment/multimedia/vibrio_cholerae.jpg Vibrio cholerae Helicobacter pylori http://helico.gsnu.ac.kr/

Cell Associations ? Coccus Diplococcus Streptococcus - filamentous Staphylococcus - colonial ? Streptobacillus

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

Cell Structure: Boundary Mycoplasma cell membrane bilayer lipopolysaccharide transport proteins cytosol regulates input/output Gram Positive Gram Negative cell wall-murein peptidoglycan muramic acid - peptide prevents bursting turgor pressure penicillin sensitive additional membrane bilayer lipopolysaccharide releases dye

Cell Structure: Boundary Defenses Capsule or Sheath mucoid polysaccharides cell adhesion chemical resistance - defense desiccation resistance Endospore spore coat + DNA + other materials exterior may be lost frozen for long periods boiled for long periods desiccated for long periods then germinates to new cell Bacillus anthracis

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

Cell Structure: Movement hook directional rotation? basal rings and rod anchorage rotation stiff helical flagellum flagellin protein is rotated by “motor apparatus” in the membrane by H+ ATPase at rates of 200-1700 rps (>12,000 rpm!) Taxis: movement toward stimulus 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)) phototaxis: movement toward light chemotaxis: movement to chemicals

Lophotrichous: flagella found at one end of the cell http://msucares.com/lawn/tree_diseases/images/bacteria.gif

Amphitrichous: flagella at both ends (but not many on sides) http://www.biophysics.uwa.edu.au/STAWA/scans/40540a.jpg Peritrichous: flagella all around cell http://www.biophysics.uwa.edu.au/STAWA/scans/40545a.jpg

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 Nucleoid - genome one circular DNA molecule no histone protein association attached to cell membrane transcription by RNA polymerase replication by DNA polymerase separation of chromosomes cytokinesis by furrowing 70S Ribosome Process called binary fission NOT mitosis! Genome and copy are identical Genome is haploid There is no synapsis There is no recombination rRNA + protein + ribozymes translation of mRNA into protein

nucleoids initial furrowing furrowing complete http://www.nature.com/news/2002/020722/full/020722-11.html