Ecological Parasitology

Lab 2: Flagellates Spring 2011

Flagellates

Classification Eukaryotes

Characteristics Flagellum (a) Binary Fission

Flagellates

•  Three main types –  “Gut dwellers”- direct transmisison –  “Blood dwellers”- indirect transmission via

vectors (anterior and posterior) –  “Macrophage dwellers”- indirect

transmission via vectors

More specialized and harmful

Gut Dwelling Flagellates

•  Trichomonas vaginalis –  No cysts –  Causes vaginal

secretions and sterility if not treated

•  Chilomastix mesnili –  Cysts –  Little harm mild

diarrhea

•  Giardia lamblia –  Common worldwide! –  Cysts –  Severe diarrhea,

chronic stomach problems

–  Feeds on small intestinal villi

Trichomonas spp. T. vaginalis

axostyle- supportive structure made of microtubules attached to base of flagella parabasal body- organelle at base of flagellum from which grows the axoneme, or “skeleton” of the flagellum costa- structure that extends along base of undulating membrane

Chilomastix mesnili

blepharoplast- organelle at base of flagellum from which grows the axoneme, or “skeleton” of the flagellum cytostome- cell mouth

Giardia lamblia

axoneme- “skeleton” of cilia and flagella. parabasal body- organelle at base of flagellum from which grows the axoneme

Flagellates

•  Three main types –  “Gut dwellers”- direct transmisison –  “Blood dwellers”- indirect transmission via

vectors (anterior and posterior) –  “Macrophage dwellers”- indirect

transmission via vectors

More specialized and harmful

Blood and Macrophage Dwelling Flagellates

•  Phylum/subphylum/class Kinetoplasta – Giant mitochondria, called kinetoplast – Kinetosome at base of flagellum (simliar to

basal body)

trypomastigote promastigote epimastigote amastigote

kinetoplast kinetosome

Blood Dwelling Flagellates

•  Trypanosoma brucei (rhodesiense, gambiense) –  African sleeping

sickness –  Invades nervous and

lymphatic systems –  Causes coma and

death Tsetse fly

kinetoplast

Blood Dwelling Flagellates

•  Trypanosoma cruzi –  Chagas disease –  Invades tissues like

heart, esophagus, colon, peripheral nervous system

Triatoma

amastigote trypomastigote

Blood Dwelling Flagellates

•  Trypanosoma equiperdum –  Causes Dourine –  Horses, donkeys –  Sexually transmitted –  No known vector –  (slide with RBCs)

Macrophage Dwelling Flagellates

•  Leishmania donovani –  “Kala azar”- visceral

leishmaniasis –  Slow, torturous death

Macrophage Dwelling Flagellates

•  Leishmania tropica –  Oriental sore-

cutaneous leishmaniasis

–  Self-healing, but risk secondary infection