1. 12 The Eukaryotes: Fungi, Algae, Protozoa, and Helminths

2. Eukaryotic Aerobic or facultatively anaerobic Chemoheterotrophic Most are decomposers Mycology is the study of fungi The Fungi

3. Mycology: The Study of Fungi Table 12.2

4. Fungi Table 12.1

5. Molds The fungal thallus consists of hyphae; a mass of hyphae is a mycelium. Figure 12.2

6. Yeasts Unicellular fungi Fission yeasts divide symmetrically Budding yeasts divide asymmetrically Figure 12.3

7. Dimorphism Pathogenic dimorphic fungi are yeastlike at 37°C and moldlike at 25°C Figure 12.4

8. Fungal Life Cycle Figure 12.7

9. Fungal Diseases (Mycoses) Systemic mycoses: Deep within body Subcutaneous mycoses: Beneath the skin Cutaneous mycoses: Affect hair, skin, and nails Superficial mycoses: Localized, e.g., hair shafts Opportunistic mycoses: Caused by normal microbiota or environmental fungi

10. Asexual Spores Sporangiosphore Conidiospore Arthrospore Blastoconidium Chlamydospore Figure 12.1

11. Conidiospores Figure 12.5a–c

12. Sexual Reproduction Plasmogamy: Haploid donor cell nucleus (+) penetrates cytoplasm of recipient cell (–). Karyogamy: + and – nuclei fuse. Meiosis:Diploid nucleus produces haploid nuclei (sexual spores).

13. Sexual Spores Zygospore: Fusion of haploid cells produces one zygospore. Figure 12.6

14. Sexual Spores Ascospore: Formed in a sac (ascus). Figure 12.7

15. Sexual Spores Basidiospore: Formed externally on a pedestal (basidium). Figure 12.8

16. Zygomycota Conjugation fungi Coenocytic Produce sporangiospores and zygospores Rhizopus, Mucor (opportunistic, systemic mycoses)

17. Zygomycete Life Cycle Figure 12.6

18. Ascomycota Sac fungi Septate Produce ascospores and frequently conidiospores. Aspergillus (opportunistic, systemic mycosis) Blastomyces dermatitidis, Histoplasma capsulatum (systemic mycoses) Microsporum, Trichophyton (cutaneous mycoses)

19. Ascomycete Life Cycle Figure 12.7

20. Basidiomycota Club fungi Septate Produce basidiospores and sometimes conidiospores. Cryptococcus neoformans (systematic mycosis)

21. Basidiomycete Life Cycle Figure 12.8

22. Anamorphs Teleomorphic fungi Produce sexual and asexual spores. Anamorphic fungi Produce asexual spores only. rRNA sequencing places most in Ascomycota; a few are Basidiomycota. Penicillium Sporothrix (subcutaneous mycosis) Stachybotrys, Coccidioides, Pneumocystis (systemic mycoses) Candida albicans (Cutaneous mycoses)

23. Economic Effects of Fungi

24. Lichens Mutualistic combination of an alga (or cyanobacterium) and fungus. Alga produces and secretes carbohydrates; fungus provides holdfast.

25. Lichens Figure 12.10

26. The Algae Eukaryotic Unicellular, filamentous, or multicellular (thallic) Most are photoautotrophs

27. Algae Table 12.1

28. Algae Figure 12.11a

29. Dinoflagellata Dinoflagellates Cellulose in plasma membrane Unicellular Chlorophyll a and c, carotene, xanthins Store starch Some are symbionts in marine animals Neurotoxins cause paralytic shellfish poisoning Figure 12.14

30. 13 Viruses, Viroids, and Prions

31. Viruses Contain DNA or RNA Contain a protein coat Some are enclosed by an envelope Some viruses have spikes Most viruses infect only specific types of cells in one host Host range is determined by specific host attachment sites and cellular factors

32. Viruses Figure 13.1

33. Helical Viruses Figure 13.4a–b

34. Polyhedral Viruses Figure 13.2a–b

35. Enveloped Viruses Figure 13.3

36. Complex Viruses Figure 13.5a

37. Viral Taxonomy Family names end in -viridae. Genus names end in -virus. Viral species: A group of viruses sharing the same genetic information and ecological niche (host). Common names are used for species. Subspecies are designated by a number.

38. Viral Taxonomy Herpesviridae Herpesvirus Human herpes virus HHV-1, HHV-2, HHV-3 Retroviridae Lentivirus Human immunodeficiency virus HIV-1, HIV-2

39. Growing Viruses Viruses must be grown in living cells. Bacteriophages form plaques on a lawn of bacteria. Figure 13.6

40. Growing Viruses Animal viruses may be grown in living animals or in embryonated eggs. Figure 13.7

41. Growing Viruses Animal and plants viruses may be grown in cell culture. Continuous cell lines may be maintained indefinitely. Figure 13.8

42. Virus Identification Cytopathic effects Serological tests Detect antibodies against viruses in a patient. Use antibodies to identify viruses in neutralization tests, viral hemagglutination, and Western blot. Nucleic acids RFLPs PCR

43. Virus Identification Figure 13.9

44. Multiplication of Bacteriophages (Lytic Cycle) Attachment: Phage attaches by tail fibers to host cell. Penetration: Phage lysozyme opens cell wall, tail sheath contracts to force tail core and DNA into cell. Biosynthesis: Production of phage DNA and proteins. Maturation: Assembly of phage particles. Release: Phage lysozyme breaks cell wall.

45. 1 2 3 Figure 13.11, steps 1–3, 6–7

46. 4 Figure 13.11, steps 4–5, 8

47. One-Step Growth Curve Figure 13.10

48. Lytic cycle: Phage causes lysis and death of host cell. Lysogenic cycle: Prophage DNA incorporated in host DNA.

49. The Lysogenic Cycle Figure 13.12

50. 2 3 4 5 6 Specialized Transduction Figure 13.13

51. Multiplication of Animal viruses Attachment: Viruses attach to cell membrane. Penetration by endocytosis or fusion. Uncoating by viral or host enzymes. Biosynthesis: Production of nucleic acid and proteins. Maturation: Nucleic acid and capsid proteins assemble. Release by budding (enveloped viruses) or rupture.

52. Attachment, Penetration, and Uncoating Pinocytosis Figure 13.14a

53. Attachment, Penetration, and Uncoating Fusion Figure 13.14b

54. Release of an Enveloped Virus by Budding Figure 13.20

55. Multiplication of DNA Virus Figure 13.15

56. DNA and RNA Viruses Compared DNA: Cellular enzyme transcribes viral DNA in nucleus. DNA, reverse transcriptase: Cellular enzyme transcribes viral DNA in nucleus; reverse transcriptase copies mRNA to make viral DNA. RNA, + strand: Viral RNA is a template for synthesis of RNA polymerase.

57. DNA and RNA Viruses Compared RNA – strand: Viral enzyme copies viral RNA to make mRNA in cytoplasm. RNA, double-stranded: Viral enzyme copies – strand RNA to make mRNA in cytoplasm. RNA, reverse transcriptase: Viral enzyme copes viral RNA to make DNA in cytoplasm.

58. Cancer Activated oncogenes transform normal cells into cancerous cells. Transformed cells have increased growth, loss of contact inhibition, tumor specific transplant and T antigens. The genetic material of oncogenic viruses becomes integrated into the host cell's DNA.

59. Oncogenic Viruses Oncogenic DNA viruses Adenoviridae Heresviridae Poxviridae Papovaviridae Hepadnaviridae Oncogenic RNA viruses Retroviridae Viral RNA is transcribed to DNA which can integrate into host DNA HTLV 1 HTLV 2

60. Latent viral infections Virus remains in asymptomatic host cell for long periods. Cold sores, shingles Presistent viral infections Disease processes occurs over a long period; generally is fatal. Subacute sclerosing panencephalitis (measles virus) Figure 13.21

61. Infectious proteins Inherited and transmissible by ingestion, transplant, and surgical instruments Spongiform encephalopathies: Sheep scrapie, Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker syndrome, fatal familial insomnia, mad cow disease PrPC: Normal cellular prion protein, on cell surface PrPSc: Scrapie protein; accumulates in brain cells forming plaques PLAY Animation: Prion Reproduction Prions

62. Some Plant Viruses Table 13.6

63. Virus Families Single-stranded DNA, nonenveloped viruses Parvoviridae Human parvovirus Fifth disease Anemia in immunocompromised patients Table 13.2 (1 of 20)

65. Double-Stranded DNA, Nonenveloped Viruses Mastadenovirus Respiratory infections in humans Tumors in animals Table 13.2 (2 of 20)

66. Double-Stranded DNA, Nonenveloped Viruses Papillomavirus (human wart virus) Polyomavirus Cause tumors; some cause cancer Table 13.2 (3 of 20)

67. Double-Stranded DNA, Enveloped Viruses Orthopoxvirus (vaccinia and smallpox viruses) Molluscipoxvirus Smallpox Molluscumcontagiosum Cowpox Table 13.2 (4 of 20)

68. Double-Stranded DNA, Enveloped Viruses Simplexvirus (HHV1 and HHV 2) Varicellavirus (HHV 3) Lymphocryptovirus (HHV 4) Cytomegalovirus (HHV 5) Roseolovirus (HHV 6) HHV 7 Kaposi's sarcoma (HHV 8) Some herpesviruses can remain latent in host cells. Table 13.2 (5 of 20)

69. Double-Stranded DNA, Enveloped Viruses Hepadnavirus (Hepatitis B virus) Use reverse transcriptase to produce DNA from mRNA. Table 13.2 (6 of 20)

70. Single-Stranded RNA, + Strand, Nonenveloped Enterovirus Enteroviruses include poliovirus and coxsackievirus. Rhinovirus Hepatitis A virus Table 13.2 (7 of 20)

71. Single-Stranded RNA, + Strand, Nonenveloped Hepatitis E virus Norovirus causes gastroenteritis. Table 13.2 (8 of 20)

72. Single-Stranded RNA, + Strand, Enveloped Alphavirus Alphaviruses are transmitted by arthropods; include EEE, WEE. Rubivirus (rubella virus) Table 13.2 (9 of 20)

73. Single-Stranded RNA, + Strand, Enveloped Arboviruses can replicate in arthropods; include yellow fever, dengue, SLE, and West Nile viruses Hepatitis C virus Table 13.2 (10 of 20)

74. Single-Stranded RNA, + Strand, Enveloped Coronavirus Upper respiratory infections SARS Table 13.2 (11 of 20)

75. Single-Stranded RNA, – Strand, One RNA Strand Vesiculovirus Lyssavirus (rabies virus) Cause numerous animal diseases Table 13.2 (12 of 20)

76. Single-Stranded RNA, – Strand, One RNA Strand Filovirus Enveloped, helical viruses Ebola and Marburg viruses Table 13.2 (13 of 20)

77. Single-Stranded RNA, – Strand, One RNA Strand Paramyxovirus Morbillivirus Paramyxovirus Parainfluenza Mumps Newcastle disease Table 13.2 (14 of 20)

78. Single-Stranded RNA, – Strand, One RNA Strand Hepatitis D virus Depends on coinfection with Hepadnavirus Table 13.2 (15 of 20)

79. Single-Stranded RNA, – Strand, Multiple RNA Strands Influenzavirus (Influenza viruses A and B) Influenza C virus Envelope spikes can agglutinate RBCs. Table 13.2 (16 of 20)

80. Crossing the Species Barrier UN 13.3

81. Single-Stranded RNA, – Strand, Multiple RNA Strands Bunyavirus (CE virus) Hantavirus Table 13.2 (17 of 20)

82. Single-Stranded RNA, – Strand, Multiple RNA Strands Arenavirus Helical capsids contain RNA-containing granules Lymphocytic choriomeningitis VEE and Lassa Fever Table 13.2 (18 of 20)

83. Single-Stranded RNA, Two RNA Strands, Produce DNA Lentivirus (HIV) Oncogenic viruses Use reverse transcriptase to produce DNA from viral genome. Includes all RNA tumor viruses Table 13.2 (19 of 20)

84. Double-Stranded RNA, Nonenveloped Reovirus (Respiratory Enteric Orphan) Rotavirus Mild respiratory infections and gastroenteritis Colorado tick fever Table 13.2 (20 of 20)