1 / 37

The Diversity of Prokaryotic Organisms

The Diversity of Prokaryotic Organisms. Chapter 11. Domains Bacteria and Archaea. One circular chromosome not in a membrane 70S ribosomes No membrane-bound organelles Binary fission rRNA provides evidence of phylogenic differences between the 2 Domains. Domain Bacteria. Proteobacteria

Download Presentation

The Diversity of Prokaryotic Organisms

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. The Diversity of Prokaryotic Organisms Chapter 11

  2. Domains Bacteria and Archaea One circular chromosome not in a membrane 70S ribosomes No membrane-bound organelles Binary fission rRNA provides evidence of phylogenic differences between the 2 Domains

  3. Domain Bacteria • Proteobacteria • Includes most of the gram-negative bacteria • Phylogeny based on rRNA studies • Common photosynthetic ancestor • few are still photosynthetic • Mythical Greek god, Proteus • Largest taxonomic group of bacteria • Classes designated by Greek letters

  4. The  (alpha) Proteobacteria • Some grow at low nutrient levels • Some have unusual morphology • Many are agriculturally important • several medically important genra

  5. The  (alpha) Proteobacteria • Human pathogens: • Bartonella - bacillus • Cat-scratch disease

  6. Obligate intracellular parasite: • Rickettsia – bacillus or coccobacilli • Arthropod-borne cause spotted fevers • R. typhi - Endemic murine typhus (fleas) • R. rickettsii - Rocky Mountain Spotted Fever (ticks)

  7. Have prosthecae: • Caulobacter • Stalked bacteria found in low nutrient aquatic environment • Hyphomicrobium • Budding bacteria found in low nutrient environment

  8. Pelagibacter • Very small with tiny genome • P. ubique is abundant marine microbe

  9. Nitrogen-fixing bacteria: • Azospirillum • Grows in association with tropical grasses and sugar cane • Rhizobia • Rhizobium, Bradyrhizobium • Infects roots of legumes forming root nodules

  10. Nitrifying bacteria : • Chemoautotrophs • Oxidize nitrogen • Nitrosomonas NH4+ NO2– (ammonium to nitrite) • Nitrobacter NO2– NO3– (nitrite to nitrate)

  11. Plant pathogen: • Agrobacterium • Inserts plasmid into plant cells, inducing tumors • Crown gall

  12. Produce acetic acid from ethyl alcohol: • Acetobacter • Gluconobacter

  13. Wolbachia • Most common infectious bacteria • Endosymbionts of insects and other animals

  14. The  (beta) Proteobacteria • Utilize nutrients diffusing from areas of decomposition of organic matter • hydrogen gas, ammonia, and methane

  15. Thiobacillus • Chemoautotroph, oxidizes sulfur: H2S  SO42– • Sphaerotilus • - hollow sheath • - polar flagella • - problem in sewage

  16. Spirillum • Large, aerobic freshwater bacterium

  17. Neisseria • N. meningitidis • Meningococcal meningitis • N. gonorrhoeae

  18. Bordetella • Aerobic, rods or coccobacillus • B. pertussis - whooping cough

  19. The  (gamma) Proteobacteria • Largest subgroup • Great variety of physiological types • Includes the enterics

  20. Beggiatoa • Chemoautotroph, oxidize H2S to S0 • Gliding motility • Beggiatoa alba is only species • Azotobacter and Azomonas • Nitrogen fixing, free-living soil bacteria • Large ovoid cell with heavy capsule

  21. Francisella • Pleomorphic • Francisella tularensis – tularemia (rabbit fever) • Resistant to many antibiotics

  22. Pseudomonas • Aerobic rods; Polar flagella • Extra-cellular and/or florescent pigments • Opportunistic pathogen • Metabolize wide variety of substrates • Resistant to many anti-microbials • Denitrification

  23. Legionella • Found in streams, warm-water pipes, cooling towers • L. pneumophilia • Causes a form of pneumonia called legionellosis • Survive inside aquatic amoeba

  24. Coxiella • Coxiella burnetii • Q fever • Obligate intracellular pathogen • transmitted via aerosols or milk • Resistant spore–like body

  25. Vibrio • Facultative anaerobic vibrio • Vibrio cholerae • Cholera • Dysentery • V. parahaemolyticus • Less severe gastroenteritis • Undercooked shellfish

  26. Pasteurella • mainly pathogens of domestic animals • Cause pneumonia and septicemia • passed to humans from cat and dogbites • P. multocidia - carried by Komodo dragon

  27. Haemophilus • inhabit mucous membranes of upper respiratory tract, mouth, vagina, and intestinal tract • require heme fraction (X factor) and NAD cofactor (V factor) • H. ducreyi • Chancroid (STD) • H. influenzae • meningitis, pneumonia, bronchitis, septic arthritis, earaches

  28. Enterobacteriales (enterics): • Facultatively anaerobic, rods • Peritrichous flagella • Most ferment glucose and other sugars • Inhabit intestinal tract of animals (humans)

  29. Escherichia Coliforms – fecal contamination UTI and Travelers Diarrhea Food poisoning – E. coli 0157:H7 Salmonella S. enterica – 2400 servors S. enterica servor typhi – typhoid fever Enterics

  30. Enterics • Shigella • Shigellosis (bacillary dysentery) • Klebsiella • K. pneumoniae – serious form of pneumonia • Some species fix nitrogen

  31. Yersinia Y. pestis – plague Proteus Swarmer cells UTI and wound infections Enterics

  32. The  (delta) Proteobacteria • Some species are predators on other bacteria • Important contributors to the sulfur cycle

  33. Bdellovibrio • Aerobic, rod with polar flagella • attack other gram (-) bacteria similar to the way a virus would

  34. Desulfovibrio • Human intestinal tract and anaerobic sediments • obligate anaerobe, sulfur reducing bacteria • Use S for final electron acceptor • Release tons of H2S annually

  35. Myxococcus • Gliding motility • Feed on bacteria they encounter • Cells aggregate to form fruiting body loaded with myxospores

  36. The  (epsilon) Proteobacteria • Microaerophilic, helical or vibrioid rods • Motile by means of flagella

  37. Campylobacter • C. fetus • causes spontaneous abortion in domestic animals • C. jejuni • leading cause of bacterial diarrhea • Helicobacter • H. pylori • common cause of stomach ulcers

More Related