BIOL 2230 REEDER

EUCARYOTIC MICROORGANISM SURVEY

I. Eucaryotic Microorganisms: Algae, Fungi, Protozoa, Animal Helminths

A. Algae

1. Representatives from both kingdoms: Protista and Monera

2. Contain one or more types of chlorophyll (a and b) plus additional pigmentation as carotenoids

(yellow, orange, or red water insoluble hydrocarbons) and phycobilins (blue or red water-soluble

protein-pigment structures) that may mask the chlorophylls

a. algae group color dependent on their pigment ratio

3. Obtain energy via photosynthesis (same as that described for cyanobacteria and higher

multicellular plants)

4. Lack vascular tissue (xylem and phloem) and airborne spores; lack multicellular reproductive

structures

5. Widely distributed in nature: sufficient light, moisture, and nutrients required

a. microscopic forms called phytoplankton float and/or swim on or near surface of both fresh and

salt water; others may grow several hundred feet below

b. most are aquatic, but some may be found terrestrially in damp soil

6. Vary in size and arrangement

a. unicellular forms vary several micrometers to a centimeter in diameter

b. multicellular colonial forms containing structurally identical cells or a complex of differentiated

cells

c. complex multicellular forms may grow greater than l00m in length possessing various

specialized structures

7. Representative phyla: Nonpathogenic

a. Chlorophyta

(green algae):

1) possible ancestors of the first land plants (most similar to higher land plants)

2) unicellular, colonial, and filamentous (cells arranged end-to-end) forms

3) cell wall of cellulose and pectin storing reserve food as starch

4) most inhabit fresh water

b. Euglenophyta (euglenids):

1) motile and unicellular; flagellated

2) Euglena: photosynthetic, but possessing many animal features

a) no rigid cell wall

b) inhabit soil and water

c. Bacillariophyta (golden-brown algae):

1) storage of food as oil and contain large amounts of the carotene carotenoid

2) mostly unicellular

3) Diatoms: two portioned cell wall of silica with many intricate shapes

a) abundant in both fresh and salt water comprising the phytoplankton

d. Phaeophyta (brown algae):

1) predominant brown pigment (fucoxanthin)

* 2) most complex of the algae

a) kelps grow over l00m long

e. Dinoflagellata:

1) contain a large representative group of unicellular, motile (two flagella) dinoflagellates

a) armor-like appearance due to the interlocking plates of cellulose and pectin

comprising their cell walls

b) spins like a top through the water

c) comprise the phytoplankton

f. Rhodophyta (red algae):

1) unicellular to filamentous forms; some grow longer than lm

2) primarily marine

3) significant in the formation of reefs by the deposit of CaCO3

* 4) Gelidium provides for the production of agar

8. Algae's commercial and ecological significance:

a. phytoplankton comprise the base of aquatic food chains

b. production of atmospheric oxygen (02)

c. used in fertilizers, food preparation, and agar production for use in microbiology

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BIOL 2230 REEDER

EUCARYOTIC MICROORGANISM SURVEY

I. Eucaryotic Microorganisms: Algae, Fungi, Protozoa, Animal Helminths A. Algae

Representatives from both kingdoms: Protista and Monera
Contain one or more types of chlorophyll (a and b) plus additional pigmentation as carotenoids (yellow, orange, or red water insoluble hydrocarbons) and phycobilins (blue or red water-soluble protein-pigment structures) that may mask the chlorophylls a. algae group color dependent on their pigment ratio
Obtain energy via photosynthesis (same as that described for cyanobacteria and higher multicellular plants)
Lack vascular tissue (xylem and phloem) and airborne spores; lack multicellular reproductive structures
Widely distributed in nature: sufficient light, moisture, and nutrients required a. microscopic forms called phytoplankton float and/or swim on or near surface of both fresh and salt water; others may grow several hundred feet below b. most are aquatic, but some may be found terrestrially in damp soil
Vary in size and arrangement a. unicellular forms vary several micrometers to a centimeter in diameter b. multicellular colonial forms containing structurally identical cells or a complex of differentiated cells c. complex multicellular forms may grow greater than l00m in length possessing various specialized structures
Representative phyla: Nonpathogenic a. Chlorophyta (green algae): 1) possible ancestors of the first land plants (most similar to higher land plants) 2) unicellular, colonial, and filamentous (cells arranged end-to-end) forms 3) cell wall of cellulose and pectin storing reserve food as starch 4) most inhabit fresh water b. Euglenophyta (euglenids): 1) motile and unicellular; flagellated 2) Euglena: photosynthetic, but possessing many animal features a) no rigid cell wall b) inhabit soil and water c. Bacillariophyta (golden-brown algae): 1) storage of food as oil and contain large amounts of the carotene carotenoid 2) mostly unicellular 3) Diatoms: two portioned cell wall of silica with many intricate shapes a) abundant in both fresh and salt water comprising the phytoplankton d. Phaeophyta (brown algae): 1) predominant brown pigment (fucoxanthin)
- 1. most complex of the algae a) kelps grow over l00m long e. Dinoflagellata:
  2. contain a large representative group of unicellular, motile (two flagella) dinoflagellates a) armor-like appearance due to the interlocking plates of cellulose and pectin comprising their cell walls b) spins like a top through the water c) comprise the phytoplankton f. Rhodophyta (red algae):
  3. unicellular to filamentous forms; some grow longer than lm
  4. primarily marine
  5. significant in the formation of reefs by the deposit of CaCO 3
- 1. Gelidium provides for the production of agar
Algae's commercial and ecological significance: a. phytoplankton comprise the base of aquatic food chains b. production of atmospheric oxygen (0 2 ) c. used in fertilizers, food preparation, and agar production for use in microbiology

B. Fungi

Lack chlorophyll and are generally nonmotile (except for some spore forms)
Unicellular (yeasts) to multicellular (long, branched, filamentous molds) forms
Some exhibit dimorphism (pathogenic forms: superficial and systemic mycoses); grow as unicellular yeasts under one set of conditions or as a filamentous mold under different circumstances a. Diphasic fungi: 1) yeast stage can grow in vivo (living tissue) or in vitro (glass tube) at 37o^ with filamentous form growing only in vitro at 25o^ C. *2) Most systemic mycoses are diphasic with the yeast stage found in living tissue a) Histoplasma capsulatum : Histoplasmosis b) Blastomyces dermatiditis: Blastomycosis
Most representatives are harmless saprophytes (decomposers of dead or decaying organic matter) requiring abundant moisture, organic matter supply and oxygen.
Yeasts: a. microscopically simple, independent cells usually round or ovoid b. are simpler cells than mold, but more complex and larger than bacteria c. all taxonomic fungal divisions contain yeasts d. most reproduce both sexually and asexually 1) usually asexually by budding 2) those yeasts able to reproduce sexually: two cells fuse forming a single, saclike ascus that will form one to eight spores e. widely distributed in nature, in water, soil, dust, and on many fruits and vegetables f. can grow facultatively using fermentation or utilize aerobic respiration; are a good source of nutrients being able to synthesize their own vitamins and proteins
Molds: a. Composed of long filaments of microscopic cells called hyphae (pl.), which may branch and intertwine to form a macroscopic filament mass called mycelium 1) each hypha may be divided into many different cells containing individual nuclei by septa (cross walls) resulting in septate hypha, or the hyphae may lack septa appearing as one long cell containing many nuclei referred to as coenocytic hypha b. hyphae cells vary in size with diameters of l0-20 um to as small as l um c. hyphal filament elongates by binary fission, but molds primarily reproduce by the formation of spores produced either sexually or asexually 1) spores are produced in large numbers and spread via wind currents or insects 2) spores will germinate if suitable conditions are found (source of organic matter, moisture, oxygen) and give rise to hyphal filaments typically forming a mycelia mass
Fungal Classification: a. Divisions: organized on the basis of the sexual reproductive structures (or lack of); *spore formation is primarily by asexual means 1) Zygomycota: fusion of opposite mating types of gametangia (n) result in a diploid zygote, which may form a resistant, black, thick walled zygospore (also 2n); forms a sporangium when it breaks dormancy to form spores; sporangia may be formed asexually as well; none are normal specific human pathogens, although Rhizopus and Mucor can be opportunistic causes of a serious, and often fatal pneumonia 2) Ascomycota (sac fungi): hyphae fusion of same or opposite mating types forms a fruiting body containing sexual spore producing sacs (asci); conidia are asexual spore-producing structures; large number of yeast representatives, as Saccharomyces; some species of Aspergillus and Penicillium; Peziza 3) Basidiomycota (club fungi): fruiting body (mushroom cap's) contains club-shaped sexual spore-producing structures; (basidium); asexual reproduction by fragmentation of conidia; few human diseases caused, but do result in several plant diseases (rusts and smuts of cereal grains); mushrooms, puffballs 4) Deuteromycota ("imperfect fungi"): no sexual stage has been observed in members of this class; many of the human fungal pathogens are represented: superficial infections of cosmetic concern, cutaneous infections of the nails, hair and stratum corneum of the skin, and sub-cutaneous and systemic infections resulting in debilitating and fatal diseases; Candida albicans, histoplasmosis, ringworm, dandruff, and athlete's foot; conidia for asexual spore production

Fusion of haploid male and female nuclei forms and oospore (diploid) that can germinate into new mycelium. a) Water molds often overwinter as an oospore. d. Examples include: downy mildew on grapes, potato bight, and the water molds Saprolegnia (parasitic) and Achlya (saprophytic). D. Protozoa: l. Animal-like representatives of Kingdom Protista

includes all of the unicellular eucaryotes, plus colonial forms composed of many independent cells possessing certain specialized functions
Structurally, a protozoan typically consists of a tough, outer pellicle (covering); a plasma membrane; an outer cytoplasmic layer (ectoplasm); an inner, granular cytoplasmic layer (endoplasm); one or two nuclei, mitochondria, food vacuoles and one or more contractile vacuoles in the cytoplasm; and structures for securing food and motility
Typically aquatic, with some forms inhabiting moist soil; most are free-living

1. Some forms live as obligate parasites of animals producing chronic to acute human diseases: parasitic forms found in all representative groups; significance of the tough pellicle and cyst stage

Many protozoa may form cysts or encyst under certain adverse environmental conditions (lack of food or moisture, adverse temperatures, exposure to toxic chemicals) a. round or oval shape possessing a heavy protective coating b. permits parasitic forms to survive period outside their host
Most exhibit holozoic nutrition ingesting solid food particles through a mouth opening or cytosome
Reproduction is primarily asexual by longitudinal binary fission; sexual change of nuclear material through conjugation
Pathogenic forms are not routinely grown, but must be identified in material later directly from the host (e.g. stools)
Representative phyla are grouped according to their mechanism of locomotion: ameboid, flagellated, or ciliated a. Phylum Sarcomastigophora (Flagellated forms)
1. One or more flagella off the forward end with a tough, flexible pellicle
2. Mouth opening or gullet; elongated shape
3. Some human parasitic forms a) Trichomoniasis: Trichomonas vaginalis - agent of common nonfatal genitourinary tract infection; sexually transmitted b) Trypanosomiasis: T.gambiense and T.rhodesiense - agents of African sleeping sickness via bite of tsetse fly vector; T. cruzi - agent of Chagas' disease of the western hemisphere; called hemoflagellates. c) Leishmaniasis: Leishmania - sandfly vector leading to either cutaneous or visceral disease features of humans. d) Giardiasis: Giardia lamblia: intestinal disease (enteritis); most frequent cause of water borne diarrhea in the U.S. b. P.Sarcomastigophora (ameboid forms)
4. Use of pseudopodia with very flexible cell body mass
5. Majority are free-living with several parasitic forms a) Entamoeba histolytica - agent of a human intestinal disease called amoebiasis or amoebic dysentery; may be asymptomatic, or may produce diarrhea and abdominal discomfort, or may produce liver and other organ abscesses, or may be fatal. c. Phylum Euglenophyta
6. flagellated forms possessing characteristics of both plants and animals; free-living; Euglena d. P. Acicomplexa
7. all are parasites of some animal host; fortunately , most are harmless
8. differences from the other phyla representatives: a) non-motile mature organism b) do not phagocytize: instead nutrition by the diffusion of soluble nutrients into the cell c) complex life cycle including both asexual and sexual stages (l) vary from requiring one to two hosts
9. Disease representatives: a) Malaria: several species of Plasmodium (vivax, ovale, malariae, and falciparum) spread by the bite of the female Anopheles mosquito; organism reproduces

asexually in the human utilizing red blood cells and sexually in the mosquito; infects 300 million people/year (*greatest killer of all the infectious diseases) b) Toxoplasmosis: Toxoplasma gondii reproduce asexually in many animals and sexually in members of the cat family; usually mild and asymptomatic infecting l million adults in the U.S. unless immunocompromised: common source via ingestion of undercooked or raw meat containing trophozoites or cysts. c) Pneumocystis carnii: rarely causes disease in a healthy human, but it has become an important cause of pneumonia in immunosuppressed individuals, especially those with AIDS e. P. Ciliophora

possess cilia and two nuclei (micronucleus controlling cell reproduction and a macronucleus controlling cellular metabolism)
primarily free-living with some parasitic types a) Balantidium coli: human intestinal parasite causing severe dysentery: Balantidiasis; human infection via ingestion of water or food contaminated with cysts present in swine feces. b) Free-living forms: Paramecium, Stentor, Vorticella. E. Animals:

Multicellular, heterotrophic organisms capable of independent motility in at lest some stage of their life cycle.
Two phyla of worms are of medical significance because they contain genera that are human parasites: a. Phylum Platyhelminthes (flatworms). b. Phylum Nematoda (roundworms).
Collective terms for these parasitic worms is helminths.
Helminths are studied in microbiology because diagnosis of helminthic infections in the clinical laboratory is usually by microscopic examination of stool specimens, body fluids, or tissue biopsy for ova or larvae of the parasite.
Representative flatworms: requires one or more intermediate hosts. a. Clonorchis sinensis: Chinese liver fluke b. Shistosoma mansoni: blood fluke c. Taenia saginata: beef tapeworm d. Taenia solium: pork tapeworm e. Echinococcus granulosus: hydatid disease
Representative roundworms: a. Enterobius vermicularis: pinworm b. Ascaris lumbricoides: ascariasis c. Necator americanus: hookworm d. Trichuris trichiura: whipworm e. Trichinella spiralis: trichinosis

Eukaryotic Microorganism Survey - Microbiology | BIOL 2230, Exams of Microbiology

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BIOL 2230 REEDER

EUCARYOTIC MICROORGANISM SURVEY