27 lecture protists!

Gram

• Botulin, tetanus• Exotoxin is made

inside bacteria and secreted out

• Exotoxin can elicit immune response

• Exotoxin can be vaccinated against

Exotoxin

• Botulin, tetanus• Exotoxin is made inside

bacteria and secreted out

• Exotoxin can elicit immune response

• Exotoxin can be vaccinated against

• G-positive

Endotoxin

• Gram negative• Have outer membrane• ENDOtoxin is released

when bacteria die• ENDOtoxin does not

elicit an immune response

Protists (28)

• All are eukaryotes • Habitat

Old classification

1. slime mold2. Algae3. Protozoa

diplomad

• Flagella• Mostly parasites• Asexual reproduction• TWO nuclei, lack

mitochondria, no Golgi

• Giardia (cause diarrhea) “looks like a happy face”

parabasalids

• Anaerobic flagellate• NO mitochondria• YES, it has a Golgi• Flagella arranged in

cluster on anterior• Commensal symbiont of

animals• Termites and

cockroaches have parabasalids in their guts

• Trichomonas (STD) transmit through toilet seat

Trichomoniasis

• Change of pH in vagina shift from 4 to 5 (less acidic)

kinetoplastids

• Kinetoplast: DNA found in mitochondria

• Some are free living and some are parasites

• Leishmania (sand fly)• Trypanosome (African

sleeping sickness)• Chagas (kissing bug)

Euglenids

• pellicle (thin, flexible outer covering)

• Chloroplast (auto or heterotrophic)

• Eyespot (stigma): detect light

• One or two flagella• Paramylon granule:

stores starch

• Euglena

Alveolates

• Alveoli (membrane bound sac)

• THREE phylum1. Dinoflagellate2. Ciliate3. apicomplexa

dinoflagellate

• marine, unicellular, photosynthetic

• possess 2 flagella• chromosomes lack

histones• bioluminescence• many are symbiont of

corals; dinoflagellates give sugar to corals; corals provide home

• coral bleaching

red tide

• explosive growth of dinoflagellates

• filter feeder (i.e. clams) eat the neurotoxin, then humans eat the clams

• Pfiesteria (dinoflagellate) make poison

Apicomplexan (sprozoan)

• harmful protist• malaria1. apicoplast (non-

photosynthetic plastid) which stores starch

2. apical complex used to penetrate host’s cell

• two or more different host species for life cycle completion

• Plasmodium sps: cause malaria

• cyclical chills• female mosquito

Anopheles

Toxoplasma (apicomplexan)

• causes toxoplasmosis• can cause blindness in

immunocompromised people

• can damage human fetus

ciliates• possess cilia to move and feed• have TWO nuclei

1. large: everyday cell function (metabolism)

2. small: sexual reproduction (conjugation)

• MOST advanced protist– gullet: food particles go in– anal pore: waste goes out

– For other protists, “same hole is used for everything,” Prof. Phommasaysy

stramenopiles (heterokontes)

• TWO flagella1. hairy2. smooth

• EXCEPT oomcytes, all have fucoxanthin (yellow-brown carotenoid)

• golden algae• brown algae– conceptide: make

gametes and zoospores

FOUR clades of stramenopiles

1. oomycetes2. diatoms3. golden algae4. brown algae

oomycetes (water molds)

• fungus-like protists• oogonia “egg fungi”

have female gametes• oogonia

• water molds: fish parasites

• white rust: tree parasites

• downy mildew: crop plant parasites

Irish potato famine

• oomycetes • Phytophthora infestans

diatoms

• photosynthetic• two-part, silica shell

called frustule

• Why are they important?– most O2 production (more

than rain forests)– food for organisms– oil (fossil fuel)– diatomaceous earth make

insectide

golden algae

• pigment fucoxanthin• biflagellated• most are freshwater

• P. Parvums

brown algae (seaweed, kelp)

• Phaeophyles• most complex, largest

algae• most are multicellular• algin

Quiz on Thursday 11/21!