1. Bacteria and Archaea Adapted for Union City High School by Greg Campbell From Campbell, N. and Reece, J. (2008). Biology 8 th Ed. San Francisco, Ca. Pearson Benjamin Cummings.

2. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes thrive almost everywhere, including places too acidic, salty, cold, or hot for most other organisms Most prokaryotes are microscopic, but what they lack in size they make up for in numbers There are more in a handful of fertile soil than the number of people who have ever lived

3. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings They have an astonishing genetic diversity Prokaryotes are divided into two domains: __________and __________. Video: Tubeworms Video: Tubeworms

4. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes are unicellular may form colonies Most prokaryotic cells are 0.5–5 µm, much smaller than the 10–100 µm of many eukaryotic cells Prokaryotic cells have a variety of shapes The three most common shapes are ______(cocci), ________(bacilli), and _________

5. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings An important feature of nearly all prokaryotic cells is their cell wall, which maintains cell shape, provides physical protection, and prevents the cell from bursting in a hypotonic environment Eukaryote cell walls are made of _______or ______ Bacterial cell walls contain _______________, a network of ___________cross-linked by _________

6. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Archaea contain polysaccharides and proteins but lack peptidoglycan Using the Gram stain, scientists classify many bacterial species into Gram-___________ and Gram-_________ __groups based on cell wall composition Gram-negative bacteria have less peptidoglycan and an outer membrane that can be toxic, and they are more likely to be antibiotic __________.

7. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Many antibiotics target ____________and damage bacterial cell walls

8. Fig. 27-3a Cell wall Peptidoglycan layer Plasma membrane Protein (a) Gram-positive: peptidoglycan traps crystal violet.

9. Fig. 27-3b Cell wall Peptidoglycan layer Plasma membrane Protein (b) Gram-negative: crystal violet is easily rinsed away, revealing red dye. Outer membrane Carbohydrate portion of lipopolysaccharide

10. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings A polysaccharide or protein layer called a ________ covers many prokaryotes

11. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Some prokaryotes have ____________(also called attachment pili), which allow them to stick to their substrate or other individuals in a colony ____________ are longer than fimbriae and allow prokaryotes to exchange ________

12. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Most motile bacteria propel themselves by _______ that are structurally and functionally different from eukaryotic flagella In a heterogeneous environment, many bacteria exhibit _________, the ability to move toward or away from certain stimuli Video: Prokaryotic Flagella (Salmonella typhimurium) Video: Prokaryotic Flagella (Salmonella typhimurium)

13. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotic cells usually lack complex ___________ Some prokaryotes do have specialized __________ that perform metabolic functions

14. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The prokaryotic genome has less DNA than the eukaryotic genome Most of the genome consists of a __________ chromosome Some species of bacteria also have smaller rings of DNA called ___________.

15. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The typical prokaryotic genome is a ring of DNA that is not surrounded by a membrane and that is located in a ____________region

16. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes reproduce quickly by ___________ and can divide every 1–3 hours Many prokaryotes form metabolically inactive ______________, which can remain viable in harsh conditions for centuries

17. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes can evolve rapidly because of their _______________________

18. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes have considerable genetic variation Three factors contribute to this genetic diversity: 1.___________________ 2.___________________ 3.___________________

19. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes reproduce by binary fission, and offspring cells are generally identical ____________rates during binary fission are low, but because of rapid reproduction, mutations can accumulate rapidly in a population High diversity from mutations allows for rapid _____________

20. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Additional diversity arises from genetic recombination Prokaryotic DNA from different individuals can be brought together in three ways: 1.____________________ 2.____________________ 3.____________________

21. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings A prokaryotic cell can take up and incorporate foreign DNA from the surrounding environment in a process called ________________ ______________is the movement of genes between bacteria by bacteriophages (viruses that infect bacteria)

22. Fig. 27-11-4 Recombinant cell Recipient cell A+A+ B–B– B–B– A+A+ A–A– Recombination A+A+ Donor cell A+A+ B+B+ A+A+ B+B+ Phage DNA

23. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings _______________is the process where genetic material is transferred between bacterial cells Sex pili allow cells to connect and pull together for DNA transfer A piece of DNA called the ____________is required for the production of sex pili The F factor can exist as a separate ________or as DNA within the bacterial ____________

24. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Cells containing the ____________function as DNA donors during conjugation Cells without the F factor function as DNA recipients during conjugation The F factor is _______________during conjugation

25. Fig. 27-13-3 F plasmid F + cell F – cell Mating bridge Bacterial chromosome Bacterial chromosome (a) Conjugation and transfer of an F plasmid F + cell

26. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings A cell with the F factor built into its chromosomes functions as a _________during conjugation The recipient becomes a _____________bacterium, with DNA from two different cells It is assumed that horizontal gene transfer is also important in archaea

27. Fig. 27-13-6 F factor Hfr cell (b) Conjugation and transfer of part of an Hfr bacterial chromosome A+A+ A–A– F – cell A+A+ A+A+ A–A– A+A+ A+A+ A–A– Recombinant F – bacterium A–A– A+A+

28. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings _____________carry genes for antibiotic resistance Antibiotics select for bacteria with genes that are ____________to the antibiotics Antibiotic resistant strains of bacteria are becoming more common

29. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings _____________obtain energy from light _____________obtain energy from chemicals _____________require CO 2 as a carbon source _____________require an organic nutrient to make organic compounds These factors can be combined to give the four major modes of nutrition: _________________, _________________, _________________, and ___________________

30. Table 27-1

31. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotic metabolism varies with respect to O 2 : – _____________________require O 2 for cellular respiration – _____________________are poisoned by O 2 and use fermentation or anaerobic respiration – _____________________can survive with or without O 2

32. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes can metabolize nitrogen in a variety of ways In _________________, some prokaryotes convert atmospheric nitrogen (N 2 ) to ammonia (NH 3 )

33. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Cooperation between prokaryotes allows them to use environmental resources they could not use as individual cells In the cyanobacterium Anabaena, photosynthetic cells and nitrogen-fixing cells called _____________ exchange metabolic products Video: Cyanobacteria (Oscillatoria) Video: Cyanobacteria (Oscillatoria)

34. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings In some prokaryotic species, metabolic cooperation occurs in surface-coating colonies called biofilms

35. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Until the late 20th century, systematists based prokaryotic taxonomy on _____________ criteria Applying molecular systematics to the investigation of prokaryotic phylogeny has produced dramatic results

36. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Molecular systematics is leading to a phylogenetic classification of prokaryotes It allows systematists to identify major new clades

37. Fig. 27-16 UNIVERSAL ANCESTOR Eukaryotes Korarcheotes Euryarchaeotes Crenarchaeotes Nanoarchaeotes Proteobacteria Chlamydias Spirochetes Cyanobacteria Gram-positive bacteria Domain Eukarya Domain Archaea Domain Bacteria

38. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The use of polymerase chain reaction (PCR) has allowed for more rapid sequencing of prokaryote genomes A handful of soil many contain 10,000 prokaryotic species Horizontal gene transfer between prokaryotes obscures the root of the tree of life

39. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Archaea share certain traits with bacteria and other traits with eukaryotes

40. Fig. 27-UN1 Eukarya Archaea Bacteria

41. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Some archaea live in extreme environments and are called ___________________. _______________live in highly saline environments _________________thrive in very hot environments

42. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings __________________live in swamps and marshes and produce methane as a waste product Methanogens are strict ____________and are poisoned by O 2 In recent years, genetic prospecting has revealed many new groups of archaea Some of these may offer clues to the early evolution of life on Earth

43. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Bacteria include the vast majority of prokaryotes of which most people are aware Diverse nutritional types are scattered among the major groups of bacteria

44. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings These gram-negative bacteria include photoautotrophs, chemoautotrophs, and heterotrophs Some are anaerobic, and others aerobic

45. Fig. 27-18b Alpha Beta Gamma Delta Epsilon Proteobacteria

46. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Many species are closely associated with eukaryotic hosts Scientists hypothesize that mitochondria evolved from aerobic alpha proteobacteria through endosymbiosis

47. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Example: Rhizobium, which forms root nodules in legumes and fixes atmospheric N 2 Example: Agrobacterium, which produces tumors in plants and is used in genetic engineering

48. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Example: the soil bacterium Nitrosomonas, which converts NH 4 + to NO 2 –

49. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Examples include sulfur bacteria such as Chromatium and pathogens such as Legionella, Salmonella, and Vibrio cholerae Escherichia coli resides in the intestines of many mammals and is not normally pathogenic

50. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Example: the slime-secreting myxobacteria

51. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings This group contains many pathogens including Campylobacter, which causes blood poisoning, and Helicobacter pylori, which causes stomach ulcers

52. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings These bacteria are parasites that live within animal cells Chlamydia trachomatis causes blindness and nongonococcal urethritis by sexual transmission

53. Fig. 27-18j 2.5 µm Chlamydia (arrows) inside an animal cell (colorized TEM)

54. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings These bacteria are helical heterotrophs Some, such as Treponema pallidum, which causes syphilis, and Borrelia burgdorferi, which causes Lyme disease, are parasites

55. Fig. 27-18k Leptospira, a spirochete (colorized TEM) 5 µm

56. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings These are photoautotrophs that generate O 2 Plant chloroplasts likely evolved from cyanobacteria by the process of endosymbiosis

57. Fig. 27-18l 50 µm Two species of Oscillatoria, filamentous cyanobacteria (LM)

58. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Gram-positive bacteria include – Actinomycetes, which decompose soil – Bacillus anthracis, the cause of anthrax – Clostridium botulinum, the cause of botulism – Some Staphylococcus and Streptococcus, which can be pathogenic – Mycoplasms, the smallest known cells

59. Fig. 27-18m Streptomyces, the source of many antibiotics (colorized SEM) 5 µm

60. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes are so important to the biosphere that if they were to disappear the prospects for any other life surviving would be dim

61. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes play a major role in the recycling of chemical elements between the living and nonliving components of ecosystems Chemoheterotrophic prokaryotes function as _________________, breaking down corpses, dead vegetation, and waste products ______________prokaryotes add usable nitrogen to the environment

62. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes can sometimes increase the availability of ___________, ___________, and __________for plant growth Prokaryotes can also “immobilize” or decrease the availability of nutrients

63. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings ____________is an ecological relationship in which two species live in close contact: a larger host and smaller symbiont Prokaryotes often form symbiotic relationships with larger organisms

64. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings In ____________, both symbiotic organisms benefit In _____________, one organism benefits while neither harming nor helping the other in any significant way In _____________, an organism called a ________ harms but does not kill its host Parasites that cause disease are called __________

65. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Some prokaryotes are human pathogens, but others have positive interactions with humans

66. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Prokaryotes cause about half of all human diseases Lyme disease is an example

67. Fig. 27-21 5 µm

68. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Pathogenic prokaryotes typically cause disease by releasing exotoxins or endotoxins Exotoxins cause disease even if the prokaryotes that produce them are not present Endotoxins are released only when bacteria die and their cell walls break down Many pathogenic bacteria are potential weapons of bioterrorism

69. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Experiments using prokaryotes have led to important advances in DNA technology Prokaryotes are the principal agents in ___________________, the use of organisms to remove pollutants from the environment

70. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Some other uses of prokaryotes: – Recovery of metals from ores – Synthesis of vitamins – Production of antibiotics, hormones, and other products

71. Fig. 27-UN3 Fimbriae Capsule Cell wall Circular chromosome Internal organization Flagella Sex pilus