Introduction to Protists

C. Beardsley, ICBM 11.01.2011

Eukaryotes and viruses: Introduction to Protists History

Leeuwenhoek and the „Little Animals“ by R. Thom, 1966, Museum of Art, University of Michigan Eukaryotes and viruses: Introduction to Protists History

Antonie van Leeuwenhoek (1673) Animalcula

Microbes were first observed using a simple microscope and reported as “animalcules” to the Royal Society of London.

Eukaryotes and viruses: Introduction to Protists History

Antonie van Leeuwenhoek (1676) Animalcula

sampled habitats: water droplets, soil, sand grains, mucus, teeth scrapings, animal feces, plant seeds, parts of insects, pepper- & hay infusions …

movements, sizes, abundances Eukaryotes and viruses: Introduction to Protists

History

Martin Frobenius Ledermüller (1760/63) Infusoria (Aufgusstierchen, dessication resistant) Lorenz Oken (1805) Urthiere (unicellular) Georg August Goldfuss (1818) Protozoa

Eukaryotes and viruses: Introduction to Protists

History

John Hogg (1861) Protoctista (unicellular kingdom)

Ernst Haeckel (1866) Protista Eukaryotes and viruses: Introduction to Protists

History

Wikipedia.org

http://nai.arc.nasa.gov/library/images

Eukaryotes and viruses: Introduction to Protists

Definition

Mostly, but not exclusively, unicellular eukaryotic organisms.

What are classification schemes based on? Eukaryotes and viruses: Introduction to Protists

Classification by Morphology & Physiology Note: term classification is neutral and only means grouping by categories! Cell membrane: naked, carbonate, silicate, cellulose, chitin, proteins...

Fotos: H. Cypionka

Eukaryotes and viruses: Introduction to Protists

Classification by Morphology & Physiology

Movement: Pseudopodia, Flagella, Cilia, Sessile

Fotos: H. Cypionka Eukaryotes and viruses: Introduction to Protists

Classification by Morphology & Physiology

Developmental stages: sexual and/or asexual reproduction

Fotos: H. Cypionka

Eukaryotes and viruses: Introduction to Protists

Classification by Morphology & Physiology

Trophic life style: phototrophic, organoheterotrophic heterotrophic: phagotrophic or osmotrophic phagotrophic: Filter feeding or Interception feeding

Fotos: H. Cypionka Eukaryotes and viruses: Introduction to Protists

Classification by Morphology & Physiology

Trophic life style: phototrophic, organoheterotrophic or mixotrophic heterotrophic: phagotrophic or osmotrophic phagotrophic: Filter feeding or Interception feeding

Fotos: H. Cypionka

Eukaryotes and viruses: Introduction to Protists

Summary: Classification schemes, and thus taxonomic definitions, were based on morphological and physiological similarities among organisms.

Concept: These similarities (or lack thereof) were inherited and “modified” by random mutation & natural selection - thus reflect phylogeny.

But within the heterogeneous group of protists no consistent classification arises from putting these phenotypical trades into some kind of serial order! Eukaryotes and viruses: Introduction to Protists

Classification by Phylogeny:

Tree of Life Based on SSU-rRNA Sequence Similarity

http://nai.arc.nasa.gov/library/images

Eukaryotes and viruses: Introduction to Protists

Classification by Phylogeny:

Phylogeny of Free-Living Aquatic Protists Based on 18S rRNA Sequence Similarity

Prymnesiophytes (Haptophytes) Dinoflagellates Ciliates Fungi Choanoflagellates Chrysophytes Chlorophytes

Diatoms Cryptomonads

Bicosoecids

Euglenoids

Kinetoplastids length of branches depicts phylogenetic relationship

Groups with Heterotrophic Nanoflagellates Sherr & Sherr 2000 Eukaryotes and viruses: Introduction to Protists

Phylogeny Does Not Reflect Trophic Life Style

Paraphysomonas foraminifera Paraphysomonas sp. Paraphysomonas foraminifera Paraphysomonas imperforata heterotrophic Paraphysomonas imperforata Metanophrys similis Paraphysomonas bandaiensis Paraphysomonas butcheri Tessellaria volvocina Mallomonas akrokomos Mallomonas annulata Mallomonas adamas Chrysophytes Mallomonas splendens Mallomonas striata Mallomonas striata Mallomonas papillosa Mallomonas rasilis Mallomonas caudata autotrophic Mallomonas matvienkoae Synura mammillosa Synura spinosa Synura sphagnicola Synura uvella Synura glabra Synura petersenii uncultured eukaryote, AY046836 uncultured eukaryote, AY046860 uncultured eukaryote, AY046844 uncultured eukaryote, AY046852 uncultured eukaryote, AY046864 Heterosigma akashiwo Heterosigma akashiwo Heterosigma carterae Chattonella subsalsa Vacuolaria virescens Pteridomonas danica Apedinella radians heterotrophic Pseudopedinella elastica Ciliophrys infusionum Rhizochromulina cf. marina autotrophic eukaryote clone OLI11025 Dictyocha speculum Hyphochytrium catenoides Developayella elegans Oomycete

0.1 Beardsley, unpub.

Eukaryotes and viruses: Introduction to Protists

Evolution

From lecture of H. Arndt, Köln Eukaryotes and viruses: Introduction to Protists

Excavata Chromalveolata Plantae Unikonta (= Archaeplastida) Discicristae Opisthokonta Hacrobia Rhizaria Holozoa Haptophyta Animals(Metazoa) Jacobozoa Heterolobosea Euglenozoa Cryptophyta Stramenopiles Alveolata Radiolaria Foraminifera Cercozoa Rhodophyta Glaucophyta Viridiplantae Nucleariidae Ichthyosporea Filasterea Parabasalida Choanoflagellates Preaxostyla Fornicata Malawimonadozoa Amoebozoa Mycobionta (Fungi) Mycobionta ?

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007 Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Parabasalida: Trichomonads: Fornicata: Diplomonads: Trichomonas vaginalis Giardia lamblia

Nucleii

dizoic: 2 nucleii, 2 cytostomes, hydrogenosomes 8 flagella, mitosomes - often described as deep branching group, probably not true anymore - anaerobic without mitochondria (secondary lost) - Trichomonas is frequent in human vaginal flora (3 - 60 % of women), usually not pathogenic - Giardia : causes diarrhea; builds cysts as resting stages Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Malawimonadozoa: Jacobozoa: Malawimonas jacobiformis Jacoba sp.

Patterson et al. 2001 - approx. 5 um in size - approx. 10 um in size - only 1 genus, freshwater & soil - 4 genera, also marine

- free-swimming heterotrophic flagellates - both groups completely unknown before 1990, but of significant interest because of their key position regarding the evolution and phylogeny of Excavata Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Heterolobosae (Myxobionta) • Do not confuse with Myxobakteria ! • Myxomycota: True Slime Molds (Plasmodium, acellular)

Physarum sp.

• Acrasiomycota: Cellular Slime Molds (Pseudoplasmodium) Dictyostelium

aggregation of cells = pseudoplasmodium production of fruiting boddies Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Euglenozoa: Euglenids

Euglena Eukaryotes and viruses: Introduction to Protists

Euglena

Throphic life style: most heterotrophic, but also phototrophic or mixotrophic

Chlorophyll a fluoresces Euglenids grazing under UV-light on bacteria

Images: www.mikrobiologischer-garten.de

Eukaryotes and viruses: Introduction to Protists

Euglenozoa: Kinetoplastida

Bodo, Rhynchomonas Trypanosoma Throphic life style : Free living heterotrophic parasitic

Lee & Patterson 2000 important bacteriovores cause sleeping sickness Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Cryptophyta

• 2 flagella • some organelles not free in cytoplasm but surrounded by an additional double membrane • protein plates

phototrophic Chilomonas

saprophytic

Rhodomonas

www.glerl.noaa.gov Eukaryotes and viruses: Introduction to Protists

Haptophyta (Prymnesiophyta) Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Stramenopiles (Heterokontobionta):

2 flagella (1 short and 1 long & hairy)

Heterokonts: - Diatoms (Bacillariophyceen)

- Chrysophyceae / Chrysomonads (Gold algae)

- Phaeophyceae (Brown algae)

Oomyceta: - Cellulose molds Eukaryotes and viruses: Introduction to Protists Stramenopiles: Diatoms

• 250 genera, ca. 100 000 species • phototrophic (1 exception) • chloroplasts with chlorophyll a & fucoxanthin • no flagella • single cells or colony forming • asexual reproduction usual, but sexual reproduction & formation of auxospores possible

Eukaryotes and viruses: Introduction to Protists Stramenopiles: Diatoms

• silica containing cell walls: silcate frustules consisting of 2 halves: epi- & hypotheca

REM of a diatom cell wall (Foto Renate Kort, Erhard Rhiel). Eukaryotes and viruses: Introduction to Protists Stramenopiles: Diatoms Pennate (Bacillariales) and central (Biddulphiales) forms

Navicula sp. Asterionellopsis glacialis

Nitzschia sp.

Coscinodiscus wailesii Chaetoceros curvisetus

Eukaryotes and viruses: Introduction to Protists Stramenopiles: Chrysomonads • phototrophic and/or heterotrophic: mixotrophic • HNF: important bacterivores Fotos: H. Cypionka

Dunaliella sp.

HNF

Synura sp. Eukaryotes and viruses: Introduction to Protists Stramenopiles: Phaeophyceae

Laminaria (kelp): by definition a protist ?

Eukaryotes and viruses: Introduction to Protists

Stramenopiles: Oomycetes

• mostly free living in water; some live in soils or as parasites • heterokont biflagellated spores depend on water • cellulose molds: cell walls consist of Cellulose and Glucane •(ß-(1-3) and ß-(1-6) glycosidic bonds • potatoe disease in Ireland (1845-49) Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Alveolata:

•membranous sacs, called “alveoli”, positioned beneath the plasma membrane

•distinct micropores through the cell surface that function in pinocytosis

•tubular mitochondrial cristae

- Dinoflagellates

- Ciliates

- Apicomplexa Eukaryotes and viruses: Introduction to Protists

Alveolata: Dinoflagellates

Throphic life style: phototrophic and/or heterotrophic: mixotrophic

- cellulose-plates Ceratium sp . - 2 flagella: operate in a transverse constriction (girdle) & a longitudinal groove (= dinocont flagellation) screw-like swimming movement

Major contributors to global marine photosynthesis!

M. Godfrey Red tide

Eukaryotes and viruses: Introduction to Protists

Alveolata: Ciliates •mostly heterotrophic filter- or interception feeders, but also photo- and mixotrophic species •complex cell structures

„mouth“

Cypionka, Grundlagen der Mikrobiologie Eukaryotes and viruses: Introduction to Protists Alveolata: Ciliates •Rows of cilia originating from the kinetosomal bases •Nucleii dimorphism

Vorticella sp.

Fotos: H. Cypionka

Eukaryotes and viruses: Introduction to Protists

Alveolata: Ciliates

Vorticella: filter feeder

www.mikrobiologischer-garten.de Eukaryotes and viruses: Introduction to Protists

Alveolata: Ciliates

Obligate anaerobic ciliates:

Important in the rumen of cattle or the intestine of termites !

Eukaryotes and viruses: Introduction to Protists Alveolata: Apicomplexa Plasmodium : causes malaria

•obligate parasitic •alternation of generation and of host

•>>100 Mio. people per year Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Protists

Actinopoda: Radiolaria

Fotos: H. Cypionka

- radiating axopodia, stiffened by microtubular bundles for locomotion & food capture Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Protists

Foraminifera - calcified shells - single- or multichambered - protoplasm in chamber

- > 4000 recent species

- > 30000 ancient species

- chalk skeletons of ancient foraminifera used as indicators for marine palaeo- temperatures Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Viridiplantae: Chlorophyta

Chlorella

Volvox: •colonies of up to 20000 • 2, 4 or no flagella cells, connected via • Autotrophic plasma bridges • functional differentiation • related to plants Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Protists

Amoebozoae:

Fotos: H. Cypionka

- pseudopodia: movement by alternating new formation and retraction - with shells (tests) or without (naked) - uni- or multinuclei - size: few micrometer up to 5 mm ( Chaos carolinense ) Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists

Mycobionta: Yeast

By definition a protist ? belongs to the fungi (Ascomycete) !

Saccharomyces sp. Eukaryotes and viruses: Introduction to Protists

root ?

Synthesis of trees by Adl et al. 2005, Keeling et al. 2005, Rodriguez-Ezpelata et al. 2007

Eukaryotes and viruses: Introduction to Protists Choanoflagellates

Solitary choanoflagellate • bacteriovores • unique: collar (microvilli) • 1 flagellum

Monosigma Acanthocorbis

Colonial choanoflagellate

Foto: van den Hoff