1. The Prokaryotes: Domains Bacteria and Archaea
Chapter 11
The Prokaryotes: Domains Bacteria and Archaea

2. Q&A
Bacteria are single-celled organisms that must absorb their nutrients by simple diffusion. The dimensions of T. namibiensis are several hundred times larger than most bacteria, much too large for simple diffusion to operate. How does the bacterium solve this problem?

3. The Prokaryotes

4. Domain Bacteria Proteobacteria
From the mythical Greek god Proteus, who could assume many shapes
Gram-negative
Chemoheterotrophic

5. The Alphaproteobacteria
Learning Objective
11-1 Differentiate the alphaproteobacteria described in this chapter by drawing a dichotomous key.

6. The Alphaproteobacteria
Pelagibacter ubique
Discovered by FISH technique
20% of prokaryotes in oceans
0.5% of all prokaryotes
1354 genes

7. The Alphaproteobacteria
Human pathogens
Bartonella
B. henselae: Cat-scratch disease
Brucella: Brucellosis
Ehrlichia: Tickborne

8. The Alphaproteobacteria
Obligate intracellular parasites
Ehrlichia: Tickborne, ehrlichiosis
Rickettsia: Arthropod-borne, spotted fevers
R. prowazekii: Epidemic typhus
R. typhi: Endemic murine typhus
R. rickettsii: Rocky Mountain spotted fever

9. Rickettsias
Figure 11.1

10. The Alphaproteobacteria
Wolbachia: Live in insects and other animals
Applications p. 307

11. Wolbachia
Applications p. 307

12. The Alphaproteobacteria
Have prosthecae
Caulobacter: Stalked bacteria found in lakes
Hyphomicrobium: Budding bacteria found in lakes
Figures 11.2b, 11.3

13. The Alphaproteobacteria
Plant pathogen
Agrobacterium: Insert a plasmid into plant cells, inducing a tumor
Figure 9.19

14. The Alphaproteobacteria
Chemoautotrophic
Oxidize nitrogen for energy
Fix CO2
Nitrobacter: NH3  NO2–
Nitrosomonas: NO2–  NO3–

15. The Alphaproteobacteria
Nitrogen-fixing bacteria
Azospirillum
Grow in soil, using nutrients excreted by plants
Fix nitrogen
Rhizobium
Fix nitrogen in the roots of plants
Figure 27.5

16. The Alphaproteobacteria
Produce acetic acid from ethanol
Acetobacter
Gluconobacter

17. Make a dichotomous key to distinguish the orders of alphaproteobacteria described in this chapter. 11-1

19. The Betaproteobacteria
Learning Objective
11-2 Differentiate the betaproteobacteria described in this chapter by drawing a dichotomous key.

20. The Betaproteobacteria
Thiobacillus
Chemoautotrophic; oxidize sulfur:
H2S  SO42–
Sphaerotilus
Chemoheterotophic; form sheaths
Figure 11.5

21. The Betaproteobacteria
Neisseria
Chemoheterotrophic; cocci
N. meningitidis
N. gonorrhoeae
Figure 11.6

22. The Betaproteobacteria
Spirillum
Chemoheterotrophic; helical
Figure 11.4

23. The Betaproteobacteria
Bordetella
Chemoheterotrophic; rods
B. pertussis
Burkholderia
Nosocomial infections
Figure 24.7

24. The Betaproteobacteria
Zoogloea
Slimy masses in aerobic sewage-treatment processes
Figure 27.20

25. Make a dichotomous key to distinguish the orders of betaproteobacteria described in this chapter. 11-2

26. The Gammaproteobacteria
Learning Objective
11-3 Differentiate the gammaproteobacteria described in this chapter by drawing a dichotomous key.

27. The Gammaproteobacteria
Pseudomonadales
Pseudomonas
Opportunistic pathogens
Metabolically diverse
Polar flagella
Figure 11.7

28. The Gammaproteobacteria
Pseudomonadales
Moraxella
Conjunctivitis
Azotobacter and Azomonas
Nitrogen fixing

29. The Gammaproteobacteria
Legionellales
Legionella
Found in streams, warm-water pipes, cooling towers
L. pneumophilia
Coxiella
Q fever transmitted via aerosols or milk
Figure 24.14b

30. The Gammaproteobacteria
Vibrionales
Found in coastal water
Vibrio cholerae causes cholera
V. parahaemolyticus causes gastroenteritis
Figure 11.8

31. The Gammaproteobacteria
Enterobacteriales (enterics)
Peritrichous flagella; facultatively anaerobic
Enterobacter
Erwinia
Escherichia
Klebsiella
Proteus
Salmonella
Serratia
Shigella
Yersinia

32. The Gammaproteobacteria
Figure 11.9a

33. The Gammaproteobacteria
Figure 11.9b

34. The Gammaproteobacteria
Pasteurellales
Pasteurella
Cause pneumonia and septicemia
Haemophilus
Require X (heme) and V (NAD+, NADP+) factors

35. The Gammaproteobacteria
Beggiatoa
Chemoautotrophic; oxidize H2S to S0 for energy
Francisella
Chemoheterotrophic; tularemia

36. Make a dichotomous key to distinguish the orders of gammaproteobacteria described in this chapter. 11-3

37. The Deltaproteobacteria
Learning Objective
11-4 Differentiate the deltaproteobacteria described in this chapter by drawing a dichotomous key.

38. The Deltaproteobacteria
Bdellovibrio
Prey on other bacteria
Figure 11.10

39. The Deltaproteobacteria
Desulfovibrionales
Use S instead of O2 as final electron acceptor

40. The Deltaproteobacteria
Myxococcales
Gliding
Cells aggregate to form myxospores
Figure 11.11

41. Make a dichotomous key to distinguish the deltaproteobacteria described in this chapter. 11-4

42. The Epsilonproteobacteria
Learning Objective
11-5 Differentiate the epsilonproteobacteria described in this chapter by drawing a dichotomous key.

43. The Epsilonproteobacteria
Campylobacter
One polar flagellum
Gastroenteritis

44. The Epsilonproteobacteria
Helicobacter
Multiple flagella
Peptic ulcers
Stomach cancer
Figure 11.12

45. Make a dichotomous key to distinguish the epsilonproteobacteria described in this chapter. 11-5

46. Nonproteobacteria Gram-Negative Bacteria
Learning Objectives
11-6 Differentiate the groups of nonproteobacteria gram-negative bacteria described in this chapter by drawing a dichotomous key.
11-7 Compare and contrast purple and green photosynthetic bacteria with the cyanobacteria.

47. Phototrophic Oxygenic photosynthesis Anoxygenic photosynthesis
light
2H2O + CO2
(CH2O) + H2O + O2
light
2H2S + CO2
(CH2O) + H2O + 2S0

48. Oxygenic Photosynthetic Bacteria
Cyanobacteria
Gliding motility
Fix nitrogen

49. Cyanobacteria
Figure 11.13

50. Anoxygenic Photosynthetic Bacteria
Purple sulfur
Purple nonsulfur
Green sulfur
Green nonsulfur

51. Purple Sulfur Bacteria
Figure 11.14

52. Make a dichotomous key to distinguish the gram-negative nonproteobacteria described in this chapter. 11-6
Both the purple and green photosynthetic bacteria and the photosynthetic cyanobacteria use plantlike photosynthesis to make carbohydrates. In what way does the photosynthesis carried out by these two groups differ from plant photosynthesis? 11-7

53. The Gram-Positive Bacteria
Learning Objectives
11-8 Differentiate the genera of firmicutes described in this chapter by drawing a dichotomous key.
11-9 Differentiate the actinobacteria described in this chapter by drawing a dichotomous key.

54. Firmicutes
Low G + C
Gram-positive

55. Clostridiales Clostridium Endospore-producing Obligate anaerobes
Figure 11.15

56. Clostridiales
Epulopiscium
Figure 11.16

57. Bacillales
Bacillus
Endospore–producing rods
Figure 11.17b

58. Bacillales
Staphylococcus
Cocci
Figure 11.18

59. Lactobacillales
Generally aerotolerant anaerobes; lack an electron-transport chain
Lactobacillus
Streptococcus
Enterococcus
Listeria
[Insert Figure 11.19]
Figure 11.19

60. Mycoplasmatales Wall-less; pleomorphic 0.1 - 0.24 µm M. pneumoniae
Figure 11.20a, b

61. Make a dichotomous key to distinguish the low G + C gram-positive bacteria described in this chapter. 11-8

62. Actinobacteria
High G + C
Gram-positive

63. Actinobacteria Actinomyces Corynebacterium Frankia Gardnerella
Mycobacterium
Nocardia
Propionibacterium
Streptomyces

64. Streptomyces
Figure 11.21

65. Streptomyces
Figure 11.21

66. Actinomyces
Figure 11.22

67. Make a dichotomous key to distinguish the high G + C gram-positive bacteria described in this chapter. 11-9

68. Nonproteobacteria Gram-Negatives
Learning Objective
11-10 Differentiate among Planctomycetes, chlamydias, spirochetes, Bacteroidetes, Cytophaga, and Fusobacteria by drawing a dichotomous key.

69. Planctomycetes Gemmata obscuriglobus
Double internal membrane around DNA
Figure 11.23

70. Chlamydias Chlamydia trachomatis Chlamydophila pneumoniae
STI, urethritis
Chlamydophila pneumoniae
Chlamydophila psittaci
Psittacosis
Figure 11.24b

71. Life Cycle of the Chlamydias
Figure 11.24a

72. Spirochetes
Borrelia
Leptospira
Treponema
Figure 11.25

73. Bacteroidetes Anaerobic
Bacteroides are found in the mouth and large intestine
Cytophaga: Cellulose-degrading in soil

74. Fusobacteria Fusobacterium Are found in the mouth
May be involved in dental diseases
Figure 11.26

75. Make a dichotomous key to distinguish Planctomycetes, chlamydias, spirochetes, Bacteroidetes, Cytophaga, and Fusobacteria

76. Domain Archaea Learning Objective
11-11 Name a habitat for each group of archaea.

77. Domain Archaea Extremophiles Hyperthermophiles Methanogens
Pyrodictium
Sulfolobus
Methanogens
Methanobacterium
Extreme halophiles
Halobacterium

78. Archaea
Figure 11.27

79. What kind of archaea would populate solar evaporating ponds? 11-11

80. Microbial Diversity Learning Objective
11-12 List two factors that contribute to the limits of our knowledge of microbial diversity.

81. Microbial Diversity Bacteria size range Thiomargarita (750 µm)
Nanobacteria (0.02 µm) in rocks
Figure 11.28

82. Microbial Diversity
PCR indicates up to 10,000 bacteria per gram of soil.
Many bacteria have not been identified because they
Haven't been cultured
Need special nutrients
Are a part of complex food chains requiring the products of other bacteria
Need to be cultured to understand their metabolism and ecological role

83. Q&A
Bacteria are single-celled organisms that must absorb their nutrients by simple diffusion. The dimensions of T. namibiensis are several hundred times larger than most bacteria, much too large for simple diffusion to operate. How does the bacterium solve this problem?

84. How can you detect the presence of a bacterium that cannot be cultured