Ch 27: The Prokaryotes Bacteria & Archaea Older: (Eu)bacteria & Archae(bacteria) (don t study Concept 27.2) Some phyla Remember: Bacterial cell structure and shapes 1
Usually very small but some are unusually large: 2 nd largest bacterium known Paramecium Epulopiscium Internal structures: PHA inclusions 2 major kinds of bacterial cell walls 2
Highly resistant Protein fibers on the surface: conjugation (sex) pilus/pili fimbria/fimbriae Motility 3
Motility: other structures Axial filaments made of endoflagella (Spirochaetes only) Grappling hooks Bacteria: (Type IV) pilus/pili Slime jets Archaea: hamus/ hami DNA ruptured cell Nutritional Modes Energy source phototroph vs. chemotroph for phototrophs (lots of variation): group PS pigments(s) 1) purple S bacteriochlorophylls a or b 2) purple non-s bacteriochlorophylls a or b 3) green S bacteriochlorophylls a + c, d, or e 4) green non-s bacteriochlorophylls a + c 5) Halobacterium bacteriorhodopsin* 6) cyanobacteria chlorophyll a + phycobilins 7) PS-protists chlorophyll a + various 8) almost all land plants chlorophyll a + b 4
Nutritional Modes (cont.) C source: autotroph vs. heterotroph Combinations (energy + carbon) chemoheterotroph chemoautotroph photoheterotroph photoautotroph Oxygen (O 2 ) use aerobe vs. anaerobe Modifiying words facultative vs. obligate Ecologically - very important; 2 examples recycling symbioses (mutualism, parasitism, commensalism) Human Microbiota: our new perspective No tissue in the human body is sterile, including reproductive tissues and, for that matter, the unborn child, Seth Bordenstein, a biologist at Vanderbilt University, says in an e-mail to The Scientist. 8/14 5
Prokaryotes can make harmful substances proteins lipopolysaccharides Latest DNA-based phylogeny for all Nature Microbiology 1: 1 (2016) DNA-based phylogeny of bacteria 6
Aquificae: Aquifex Old lineages? thermo/hyperthermophiles Deinococci & Thermi: Deinococcus radiodurans Thermus aquaticus = Taq TEM DNA-based phylogeny of bacteria Chloroflexus DNA-based phylogeny of bacteria = blue-green bacteria chlorophyll a + phycobilins: phycoerythrin & phycocyanin Gloeocapsa Spirulina 7
Azolla (fern) + Anabaena (cyanobacterium) ->symbiosis (inside a leaf pocket) DNA-based phylogeny of bacteria Chlorobium in our gut: Bacteroides thetaiotaomicron DNA-based phylogeny of bacteria: Proteobacteria 8
Alpha Proteobacteria Rhodobacter (purple non-s) Agrobacterium also: Rickettsia rickettsia mitochondria nodules Most numerous bacteria on earth: Wolbachia spp. (affect their host s reproduction) close relatives: insect egg mitochondria Beta Proteobacteria Neisseria gonorrhoeae Neisseria meningitidis Rubrivivax (purple non-s) 9
Gamma Proteobacteria Vibrio cholerae Chromatium Salmonella typhi Legionella Escherichia coli Delta Proteobacteria Myxobacteria Epsilon Proteobacteria Nobel Prize Med. 2005 Campylobacter 10
DNA-based phylogeny of bacteria: Chlamydiae DNA-based phylogeny of bacteria Borrelia burdorferi DNA-based phylogeny of bacteria: Gram Positives 11
Firmicutes: Clostridium Clostridium tetani Clostridium botulinum Clostridium difficile Firmicutes: Bacilli Lactobacilli Bacillus Lactobacillus Staphylococcus Streptococcus Tenericutes = mycoplasmas (recently separated from Firmicutes) Mycoplasma pneumoniae 12
Actinobacteria = actinomycetes (aka High G+C Gram + s) Mycobacterium tuberculosis M. leprae and Bifidobacterium Crenarcheota Geogemma ( strain 121 ) Pyrodictium Sulfolobus 13
Methanobacterium Euryarcheota Halobacterium Picrophilus Owens Lake T, A, and K groups - not well known Where do we belong? 14