Eukaryotic Microorganisms: Classification and Characteristics

1. Eukaryotic Microorganisms - Chapter 12 From Biol 131 - You are expected to read and understand the fundamental characteristics of eukaryotic and prokaryotic cells (see Chapter 3 of the Bauman text) Not responsible for all the detailed characteristics of the microbes (such as different fungal sexual reproduction) used for their taxonomic classification – only what is presented in class Be sure to read sections in other chapters about example diseases and pathogens Eukaryotes

2. How are eukaryotes classified? What are the distinguishing characteristics of “algae, “protozoa” and “fungi”? Eukaryotes

3. How can we explain the origins of different photosynthetic protists? Review Endosymbiosis from Biol 131 -- see end of Chapter 3 Eukaryotes

4. Characteristics of Non-Photosynthetic Protists (Protozoa) heterotrophic or 2O Ps no cell wall cytosome contractile vacuole most are motile some stalked some have multiple nuclei Contractile vacuole Eukaryotes

5. Kinetoplastids (Kingdom Euglenozoa) -- have weird mitochondrial DNA Some are important pathogens Trypanosoma (see chap 20) African sleeping sickness -- trypanosomiasis -- Tse-tse fly Chagas disease -- American trypanosomiasis Eukaryotes

6. Amoeba Kingdom Amoeba Most common – indefinite form Extend ‘pseudopeds’ A few are pathogenic e.g., Entamoeba sp Kingdom Rhizaria -- Related to amoeba Foraminifera form outer “shell” e.g., Can be ‘huge’ (mm’s) Fossil markers Foraminiferan Amoeba feeding Eukaryotes

7. Kingdom Aveolata -- have aveolar sacs below membrane Ciliates Cilia functions: Locomotion Feeding 2 nuclei Stentor feeding Eukaryotes

8. Aveolates, cont. Apicomplexans e.g., Plasmodium, Cryptosporidium -- all pathogens -- multiple life stages -- vector transmitted Possess “apical complex” -- microtubules & other components -- used to infect host cell Have different life stages sporozoite merizoite Eukaryotes

9. Plasmodium causes Malaria (chapt 21) (Apicomplexan) Visit CDC web site http://www.cdc.gov/MALARIA/disease.htm Anopheles mosquito Complex life cycle sporozoites trophozoites merizoites Sexual reproduction Disease children adults Treatment Plasmodium Life Cycle Eukaryotes

10. Classification of Photosynthetic Protists (Algae) Primary Symbionts Chlorophyta Rhodophyta Secondary Symbionts Euglenoids Chrysophyta Dinoflagelates Phaeophyta Eukaryotes

11. Chlorophyta are now classified in Plantae Similarities in - Cell wall structure -- cellulose - Chloroplast structure -- primary endosymbiosis - Photosynthetic process Diversity in cellular organization’ -- unicellular -- filamentous -- colonial Eukaryotes

12. Euglenoids and Diatoms -- 2O endosymbiosis Euglenoids (Kingdom Aveolata) -- light senstitive ‘eye spot’ Diatoms(Kingdom Stramenopila) - Siliceous cell walls Diatoms Eukaryotes

13. Dinoflagellates (Kingdom Alveolata) -- Chloroplasts via 2O endosymbiosis -- phytoplankton Pfiesteria -- neurotoxin -- red-tides See EPA site on Pfiesteria and red tides http://ivy3.epa.gov.tw/OMISAR/Data/OMISAR/prjdoc/bam1.3/Pfiesteria.html Dinoflagelate Eukaryotes

14. Kingdom Rhodophyta (1O endosymbiosis) Kingdom Phaeophyta (2O endosymbiosis) -- common “marine macroscopic algae” -- specialized structures Colors vary widely Pigments optimized for light abs Chondrus crispus Eukaryotes

15. Components of Rhodophyta cell walls are sources of thickening agents -- Agar (Gelidium) -- Alginates (var. sources) -- Carrageenan (Chondrus crispus) In foods, industrial, pharmaceuticals applications -- syrups, ice cream, candies, jams… -- paints, adhesives, paper coatings,… -- creams, shampoos, capsules etc … Algae are very important as producers of ecosystems -- phytoplankton -- macroscopic algae Involved in symbiotic relationships -- invertebrates -- lichens Eukaryotes

16. Fungi (Mycology) Read section in book thoroughly Basic Characteristics -- cell walls (chitin) -- heterotrophic Common Shapes Yeasts (spherical) e.g., Saccharomyces Molds (filamentous) hyphae mycelium Dimorphism is common Eukaryotes

17. How do fungi reproduce? Asexual budding spores & sporangia Sexual ‘+’ and ‘-’ types mushrooms Budding yeasts Eukaryotes

18. How are Fungi Classified? Characteristics of sexual reproduction structures Ascomycota -- e.g., Penicillium; morels Saccharomyces Basidiomycota -- e.g., Rusts; Coprinus Zygomycota -- e.g., Rhizopus Or based on other traits Glomeromycota -- mycorrhizal fungi Read more thorough descriptions of fungal groups in text. Note: Deuteromycota is no longer a recognized fungal group. Eukaryotes

19. Ecology & Nutrition Decomposers Symbiosis mycorrhizae lichens Predators?? -- nematophagus fungi -- Arthrobotrys (ascomycota) Vid 1 Vid 2 Vid 3 Eukaryotes

20. Entomophagus Fungi Cordyceps (ascomycota) is important pathogen of insects Cordyceps Eukaryotes

21. Fungi as Plant Pathogens Agricultural threats ‘Rust diseases’ Dutch elm disease Ophiostoma ulni (Ascomycota) Other Impacts on Humans Ergot poisoning Claviceps (Ascomycota) mycotoxins Irish potato famine Phytophthora infestans (Alveolata) American Elms before and after Dutch elm blight (Minnesota Department of Agriculture) Eukaryotes

22. In 1940s, Marietta had approximately 2000 American elm trees. How many remain in 2014? Eukaryotes

23. candidiasis Fungal human pathogens “Mycoses” (Chap 19) (cutaneous vs systemic) Trychophyton rubrum -- Ascomycota -- associated with many Tineas tinea capitis (“ringworm”) tinea pedis tinea cruris Candida albicans -- Ascomycota -- mucus membrane / vaginal infections -- AIDS Treatments -- challenging -- Ergosterol metabolism Wiki on antifungals: http://en.wikipedia.org/wiki/Antifungal_drug Trychophyton rubrum Candida albicans Eukaryotes

24. Fungi pathogens, con’t. Subcutaneous / Systemic -- some endemic to our area Blastomycosis See Chap 22 & CDC web page See CDC web page: http://www.cdc.gov/fungal/diseases/blastomycosis/index.html Pulmonary Blastomycosis Eukaryotes