Kingdom Protista

Kingdom: Protista
Outline: Kingdom Protista (Chapt 29)
¾
¾
¾
¾
Characteristics of Protists
Endosymbiosis
Classifying Protists
Six monophyletic clades & about 14 Phyla
ƒ Diplomonads
…and…
ƒ Euglenozoa
Protists without a clade
ƒ Alveolata
Amoebas & Radiolarians
ƒ Stramenopila
Foraminiferans
ƒ Rhodophyt
ƒ Choanoflagellida Slime Molds
General Biology of Protists
The first eukaryote?
Cell Organization
Eukaryotic, Unicells, Colonials and Multicellular
Cell surface
Plasma membrane – always
Pelomyxa palustris –
amoeba-like ancient protist
Extracellular Material (“wall”)…chitin, cellulose, silica
Locomotion
Some don’t move
Some move….pseudopodia, flagella, cilia
Dormancy
Nutrition
Cyst formation …..Cell Metabolism shuts down
….. Protects Cell from adverse conditions
Fairmead pond in Epping Forest
Photoautotrophs
Heterotrophs: phagotrophs & osmotrophs
Mixotrophs
Asexual….. mitosis and cytokinesis
Reproduction
….. Binary fission (equal division of cytoplasm)
….. Budding (unequal division of cytoplasm)
….. Schizogony – many nuclear divisions… several cells
Sexual ….. Meiosis & union of haploid gametes
Eukaryotic Cell Origins
1. Internal membranes like eukaryotes
2. Nuclei 1- many
3. Nuclear mitosis …Nucleus pinches in two
4. NO mitochondria… but
Æ Symbiotic bacteria live in cytoplasm
5. Resembles Archaebacteria
fiEukaryotes evolved from Archaebacteria ??
Eukaryotic Cell Origins - Endosymbiosis
Ancestral eukaryotic cell &
internal membrane system
The nucleus and
endoplasmic reticulum
arose from infoldings
of prokaryotic cell
membrane
Chloroplast
Aerobic
bacterium
Photosynthetic
Bacterium
Hetrotrophic
Eukaryotic cell with
mitochondrion
Mitochondrion
Photosynthetic
organisms
Eukaryotic cell
with chloroplasts
1
Evolutionary Relationships Among Six Kingdoms
Overview of Protist Classification
Protista
ia
er h
ct Arc
a
B
ia
er
ct
a
ab
ae
ts
an
Pl gi
n
Fu
im
An
s
al
Endosymbiosis
Protists
Eukaryotic cell organization
Paraphyletic
200,000+ species
7 Major Monophyletic groups
15 major phyla
Eukaryote Clade
Ancestral Prokaryote
Overview of Protist Classification
Dinoflagellates
Apicomplexans
Ciliates
Diplomonads & Parabasalids
Diplomonads – Giardia intestinalis
Choanoflagellates
Intestinal parasites
a ls
l ag
300,000,000 per gram of feces
No mitochondria
Two nuclei
Multiple flagella
NO ER
No golgi
No lysosomes
Overview of Protist Classification
Clade?
te s
e lla
l ag
a ls
Amoebas
Forams
Slime molds
Green algae
Ani
m
Live with cellulose digesting bacteria
Alv
eol
at a
Termite gut parasites
Dip
lo
Par mona
ab a
d
s a li s
ds
Eug
len
ozo
a
Undulating membrane
Brown algae
Diatoms
Oomycetes
Choanoflagellates
i
Cho
an o
f
Euglenoids
Kinetoplastids
Red Algae
Fun
g
Dinoflagellates
Apicomplexans
Ciliates
oph
yta
Chlo
roph
yta
Plan
ts
Diplomonads
Parabasalids
5 flagella
No mitochondria
Nuclei in trophozoite
Rho
d
Ani
m
i
Cho
an o
f
Motile & cyst stages
en o
p ila
Diplomonads & Parabasalids
Parabasalids
e lla
te s
Ancestral Eukaryote
Fun
g
oph
yta
Chlo
roph
yta
Plan
ts
Clade?
Rho
d
Stra
m
Amoebas
Forams
Slime molds
Hiker’s diarrhea, nausea, vomiting
Green algae
Stra
m
Brown algae
Diatoms
Oomycetes
oa
Alv
eol
at a
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
Red Algae
en o
p ila
Diplomonads
Parabasalids
Trichomonas vaginalis
Causes STD Æ Vaginitis
Ancestral Eukaryote
2
Lineage Euglenozoa: Euglenoids
Euglenozoa: Euglenoids
– 40 genera, single-celled, mostly freshwater
– 1/3 photoautotrophic, 2/3 heterotrophic
– Motile – Move by flagella
EM views of pellicle
Euglenozoa:
Kinetoplastids
Kinetoplastid Characteristics
Genus: Trypanosoma
Kinetoplastid
(mitochondrion)
Kinetoplastid = One mitochondrion per cell
–Mitochondrion extends full length of cell
–Mitochondrial genome = kinetoplast
–Kinetoplast DNA
Maxicircles 50 per cell
15 & 80 Kbp
Minicircles 10,000 per cell
0.9 & 2.5 Kbp
Function:Rapid glycolysis
DNA editing by RNA
Kinetoplast
minicircles
Kinetoplast in mitochondrion
Diseases caused by Trypanosomes
1. Sleeping sickness, leishmaniasis & Chagas’ disease
2. > 4 million affected annually
3. Control difficult:
2000 variable cell membrane glycoprotein genes
Kinetoplast
Diseases caused by Trypanosomes – Leishmaniasis
1. tropical/subtropical: 88 countries
2. 2 million infections
cutaneous
visceral (internal organs)
3. Vector Æ sand fly
Macrophage filled
with leishmania trypanosomes
Sand fly vector
3
Kissing bug
Early infection
Overview of Protist Classification
Dinoflagellates
Apicomplexans
Ciliates
Red Algae
Brown algae
Diatoms
Oomycetes
e lla
l ag
a ls
Ani
m
i
Cho
an o
f
Fun
g
oph
yta
Chlo
roph
yta
Plan
ts
te s
Green algae
Amoebas
Forams
Slime molds
Clade?
Choanoflagellates
Rho
d
en o
p ila
Euglenoids
Kinetoplastids
Stra
m
Diplomonads
Parabasalids
Alv
eol
at a
1. Disease agent = Trypanosoma cruzi
2. Vector Æ Kissing bug & blood transfusions
3. 30 million people infected (Central & South America)
4. Symtoms: acute: swollen eye, fever, fatigue, organ
involvement, brain swelling
chronic: 10-20 yrs later
weakened cardiac muscle
megacolon
Dip
lo
Par mona
ab a
d
s a li s
ds
Eug
len
ozo
a
Diseases caused by Trypanosomes – Chagas’ Disease
Ancestral Eukaryote
Infected muscle
Alveolata: Dinoflagellates
¾Alveolus = vesicles below plasma
membrane
¾Single-celled, 2 flagella in grooves
2100 species mostly marine
¾Cell Wall – sometimes present
Cellulose plates, maybe some silica
¾Nutrition – about 50% autotrophic
alveolus
Chloroplasts with 3 membranes
Chlorophyll a, c
Carotenoids: fucoxanthin
¾Chromosomes
No histones with DNA
Attached to Nuclear Membrane
Condensed throughout interphase
¾Importance (autotrophs)
40% global productivity
Zooxanthellae
Red tides
Bioluminescence
Bonaire coral
Alveolata: Dinoflagellates
Ceratium – A planktonic
dinoflagellate
Alveolata: Dinoflagellates
Dinoflagellate blooms = red tides
Pfiesteria bloom
Noctiluca bloom Æ saxotoxin
Na+ channel blocker
Zooxanthellae
symbiotic dinoflagellates
Coral
jellyfish
Spotted jellyfish with zooxanthellae
Bleached coral lacking zooxanthellae
4
Alveolata: Dinoflagellates
Bioluminescent
dinoflagellates
Pfiesteria fish kill in
Chesapeake Bay
Noctiluca cells
Menhaden with lesions
Overview of Protist Classification
Brown algae
Diatoms
Oomycetes
te s
e lla
l ag
a ls
Ani
m
Clade?
Green algae
i
Cho
an o
f
Amoebas
Forams
Slime molds
Choanoflagellates
oph
yta
Chlo
roph
yta
Plan
ts
Alv
eol
at a
Dip
lo
Par mona
ab a
d
s a li s
ds
Eug
len
ozo
a
Euglenoids
Kinetoplastids
Red Algae
Fun
g
Dinoflagellates
Apicomplexans
Ciliates
Rho
d
Diplomonads
Parabasalids
en o
p ila
Bioluminescence in Pyrodinium bahamense
Stra
m
Alveolata: Dinoflagellates
Ancestral Eukaryote
Group: Alveolata
Apicomplexans
Example: Plasmodium
• Api = apical
• complexa = complex
Group: Alveolata Apicomplexes
Plasmodium & Malaria
• Apical end of cell Æ complex
mass of organelles…
– Microtubules
– Fibrils
– Vacuoles
• All parasites of animals
• Unicells
• Nonmotile
Alveolar sac &
apical complex
5
Group: Alveolata Apicomplexes
Plasmodium & Malaria
Group: Alveolata Apicomplexes
Plasmodium Æ Malaria
Occurrence: 500 million people infected globally
1 billion people at risk
2 million deaths annually
Schizont –
multinucleate
stage
CLINICAL PICTURE:
Cyclical chills & Fever
Incubation period: days to years
Headache, enlarged spleen
Adult respiratory distress syndrome
Severe hemolysis
Renal failure
Incubation: Days to Years
Trophozoite ring stage
Merozoites
released from red
blood cells
Gametocyte
Group: Alveolata
Ciliates
Example:Paramecium
Overview of Protist Classification
Brown algae
Diatoms
Oomycetes
•
•
•
•
•
•
te s
e lla
a ls
l ag
8000 species
Heterotrophic…but…
Unicellular
Many Cilia
Pellicle = flexible covering
Gullet = cytostome
Ani
m
i
Cho
an o
f
Clade?
oph
yta
Chlo
roph
yta
Plan
ts
Amoebas
Forams
Slime molds
Choanoflagellates
Green algae
Rho
d
en o
p ila
oa
Alv
eol
at a
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
Red Algae
Fun
g
Dinoflagellates
Apicomplexans
Ciliates
Stra
m
Diplomonads
Parabasalids
Ancestral Eukaryote
P. bursaria with endosymbiotic alga
Group: Alveolata Ciliates
Example:Paramecium
Group: Alveolata Ciliates
Example:Paramecium
•Vacuoles – Two types
Food
Contractile
•Nuclei – two
Micronucleus
Macronucleus
Video of contractile vacuole
6
Group: Alveolata Ciliates
Example:Paramecium
Fig. 35.22a
Group: Alveolata Ciliates
Example: Paramecium
Reproduction
¾ Asexual reproduction
mitosis & cytokinesis
Sexual reproduction
1. different mating types fuse
2. meiosis of micronuclei
3. 3 of 4 degenerate
4. remaining micronuclei divide
mitotically
5. micronuclei exchange
6. fuse to form diploid micronuclei
Trichocysts
Apicomplexes
Ciliates
te s
e lla
l ag
a ls
Ani
m
Clade?
i
Cho
an o
f
photosynthetic…plankton &
endosymbionts
heterotrophic…Plasmodium
mixotrophs…Paramecium
Amoebas
Forams
Slime molds
Green algae
Fun
g
mixotrophic Euglena
heterotrophic Trypanosoma
Choanoflagellates
oph
yta
Chlo
roph
yta
Plan
ts
Euglenoids
Kinetoplastids
Red Algae
Brown algae
Diatoms
Oomycetes
Rho
d
Alveolata
Dinoflagellates
Dinoflagellates
Apicomplexans
Ciliates
Alv
eol
at a
Euglenozoa
Euglenoids
Kinetoplastids
heterotrophic parasites
Dip
lo
Par mona
ab a
d
s a li s
ds
Eug
len
ozo
a
Diplomonads &
Parabasalids
Overview of Protist Classification
Diplomonads
Parabasalids
Stramenopila
Summary of Protists Examined Thus Far
Ancestral Eukaryote
Group Stramenopila – Brown Algae
Group Stramenopila –Characteristics
1.Flagella: Fine hairs on flagella
1.Tinsel type has mastigonemes (fine hairs)
2.Whiplash – no hairs
2.Cell wall: cellulose
3.Nutrition: Autotrophs & Heterotrophs
1.Autotroph chloroplasts
1.chlorophyll a and c
2.carotenoid pigments = fucoxanthin
4.Three groups
1.Brown algae
2.Diatoms
3.Oomycetes = water molds
Brown algae
Live video feed
Video Link Kelp
7
Group Stramenopila
Group Stramenopila – Brown Algae Macrocystis
Brown Algae Æ Kelp
Stramenopila – Brown Algae Intertidal habitat
Stramenopila
Brown Algae
Ecological Importance
Stramenopila
Brown Algae
Sargasso sea – a Kelp-dominated ecosystem
Brown algae
Economic Importance
Additives
Food
Stabilizers
Binding agents
Kombu
Sargassum
8
Group Stramenopila
Overview of Protist Classification
te s
e lla
l ag
a ls
i
Cho
an o
f
Fun
g
Clade?
Diatoms
¾Unicells, 11,000 species
ƒ50% marine
¾Double shells (Wall) Silica
Green algae
oph
yta
Chlo
roph
yta
Plan
ts
Amoebas
Forams
Slime molds
Choanoflagellates
Rho
d
oa
Alv
eol
at a
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
Red Algae
Brown algae
Diatoms
Oomycetes
Ani
m
Dinoflagellates
Apicomplexans
Ciliates
Stramenopila
Diplomonads
Parabasalids
¾Autotrophic
¾Pigments
ƒChlorophyll a, c
ƒCarotenoids
ƒFucoxanthin
¾Food reserve
Chrysolaminarin
Oils
¾Importance
40% global productivity
Abrasives & filter aids
Ancestral Eukaryote
Group Stramenopila
Diatoms
Silica shells & Symmetry
Diatom Commercial Applications
Dynamite
Pennate
Centric
Filter
Overview of Protist Classification
te s
e lla
Ani
m
a ls
l ag
i
Cho
an o
f
Clade?
Choanoflagellates
oph
yta
Chlo
roph
yta
Plan
ts
Amoebas
Forams
Slime molds
Group Stramenopila - Oomycetes
Water molds & downy mildews
Green algae
Rho
d
Alv
eol
at a
oa
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
Red Algae
Brown algae
Diatoms
Oomycetes
Fun
g
Dinoflagellates
Apicomplexans
Ciliates
Stramenopila
Diplomonads
Parabasalids
9Heterotrophic Protists
9Aquatic: Fresh or salt water
9Terrestrial: Soil
9Parasitic or saprotrophic
9Hypha & Hyphae
9Cellulosic walls
Ancestral Eukaryote
9
Group Stramenopila Oomycetes
Reproduction in Saprolegnia – a water mold
Group Stramenopila
Oomycetes
Saprolegnia (water mold)
Vegetative hyphae
Oogonium with
eggs
Antheridium with
sperm
Zoosporangium
with zoospores
Group Stramenopila Oomycetes
Plasmopara (downy mildew)
on grapes
Irish Potato Famine & Late Blight
1845-49 1 million deaths
Late 1900’s 1.1 million emigrated
Phytophthora
Overview of Protist Classification
te s
e lla
a ls
Ani
m
i
Cho
an o
f
l ag
yta
Chlo
roph
Clade?
Green algae
Plan
ts
Amoebas
Forams
Slime molds
Rhodophyta
Red Algae
¾Distribution: 98% marine – 7000sp
¾Locomotion: None
Brown algae
Diatoms
Oomycetes
Rhodophyta
oa
Alv
eol
at a
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
¾Size: Microscopic to macrophytes
Choanoflagellates
Red Algae
Fun
g
Dinoflagellates
Apicomplexans
Ciliates
Stramenopila
Diplomonads
Parabasalids
¾Pigments: chlorophyll a
Phycocyanin & phycoerythrin
¾Storage material:
Floridean Starch and mannitol
¾Cell Wall: Cellulose & biocolloids
¾Importance: Producer organisms
Marine Environments
Ancestral Eukaryote
10
Rhodophyta
Red algae
Morphology
Porphyridium
Halosaccion
Palmaria palmata (dulse)
Antithamnion
Porphyra (nori)
Lithothamnion
Rhodophyta
Ecological Importance
Himantothallus in Antarctica
Phylum: Rhodophyta Economic Importance
Agar in petri dish
encrusting red alga
Agars & carrageenans
= sulfated polysaccharide
Stiffening agent in media
Slow-release drugs
Stabilize emulsions
cosmetics
film
shaving soap
hand lotion
Gelatin substitute
cheese
mayonnaise
puddings
jellies
lamellate red alga
¾ Size and habit of growth
Overview of Protist Classification
Dinoflagellates
Apicomplexans
Ciliates
Green algae
Chlorophyta
Green Algae
¾ Pigments:
Chlorophyll a, b
Carotenoids
¾ Storage material
a ls
Starch
Ani
m
Fungi
Plan
ts
Clade?
Rhodophyta
Amoebas
Forams
Slime molds
Choanoflagellates
Choanoflagellates
Chlorophyta
oa
Alv
eol
at a
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
7000 species, mostly fresh water
Enormous diversity
Red Algae
Brown algae
Diatoms
Oomycetes
Stramenopila
Diplomonads
Parabasalids
¾ Cell Wall
Cellulose & pectins
¾ Locomotion:
Many have flagellated stage
Ancestral Eukaryote
11
Chlorophyta Morphology
Unicells
Filamentous
Branched, filamentous
Chlorophyta Freshwater Habitat
Spirogyra
Colonial
Membranous
Complex
Chlorophyta – Spirogyra
Vegetative
filament
Conjugating Zygotes
filaments
forming
Cladophora in Bighorn River
Zygospores
Chlorophyta Snowfield Habitat
Chlorophyta: Importance
1. Producer organisms
2. Food?
Chlorella …a place in space
3. Sewage treatment Scenedesmus
…accumulates nitrates & phosphates
4. Fuel? Plant Physiol, November 2001, Vol. 127, pp. 740-748
Chlamydomonas
Autotrophic Protists – Green
algae
Hydrogen Production. Green Algae as a Source of Energy
12
Overview of Protist Classification
a ls
•
•
•
•
Colonial Heterotrophic protists
Single emergent flagellum
Collar – strains bacteria
Closely related to sponges… and
animals
Ani
m
Fungi
Choanoflagellates
Chlorophyta
Clade?
Plan
ts
Amoebas
Forams
Slime molds
Choanoflagellates
Green
algae
Rhodophyta
oa
Alv
eol
at a
eno
z
Eug
l
Red
Algae
Brown algae
Diatoms
Oomycetes
Euglenoids
Kinetoplastids
Dip
lo
Par mona
ab a
d
s a li s
ds
Choanoflagellida - Choanoflagellates
Dinoflagellates
Apicomplexans
Ciliates
Stramenopila
Diplomonads
Parabasalids
Collar of sponge
Choanoflagellate
collar
Ancestral Eukaryote
Protists – Rhizopoda – True Amoebas
Other Protists
• Amoebas, Radiolarians & Foraminiferans
• Slime Molds
•
•
•
•
•
No permanent locomotor apparatus
Amorphous
Move by pseudopodia
No cell walls
No meiosis
Entamoeba histolytica
Protists – Actinopoda - Radiolarians
Amoeboid Protists – Radiolarian Tests (shells)
• Marine planktonic amoebas – few hundred species
• Test - glassy silica exoskeletons
• Planktonic – mostly warm, equatorial waters
Actinoma
Actinosphaerium
13
Amoeboid Protists - Radiolarians
Axopodia Needle-like podia Extrude out of pores
Protists – Foraminifera
•Heterotrophic Marine protists
•Planktonic or Bottom Dwellers
Symbiotic
Dinoflagellates
•Pore-studded shell = test
•Organic material + CaCO3
•Multichambered
•Podia emerge from test
•Swimming
•Gathering
•Feeding
•Great Fossil Record
Radiolarians
Cretaceous extinction
Fossil forams and mass extinction
K/T
boundary
Post-impact
tertiary forams.
1cm above K/T
layer
65mya
Pre-impact
Cretaceous
(fossil) forams.
2 cm below the
K/T layer
Foraminifera
White Cliffs of Dover
Protists: Slime Molds
Example: Physarum
•500 species
•Heterotrophic Protists
•plasmodium
•Multinucleate
•Amoeboid like
streaming of cytoplasm
Fossil forams
Recent Forams
14
Slime mold sporangia
Overview of Protist Classification
a ls
Ani
m
Fungi
Chlorophyta
Clade?
Plan
ts
Amoebas
Forams
Slime molds
Choanoflagellates
Green
algae
Rhodophyta
oa
Alv
eol
at a
eno
z
Eug
l
Dip
lo
Par mona
ab a
d
s a li s
ds
Euglenoids
Kinetoplastids
Red
Algae
Brown algae
Diatoms
Oomycetes
Choanoflagellates
Dinoflagellates
Apicomplexans
Ciliates
Stramenopila
Diplomonads
Parabasalids
END
END
Protists
Multicellular Algae
Ancestral Eukaryote
15