Basic fungal biology presentation lecture.ppt

Lecture material of fungi

1. Introductory Mycology BOT 461/561

2. What are fungi?
•Eukaryotic, spore-bearing, heterotrophic
organisms that produce extracellular
enzymes and absorb their nutrition.

3. Body Plan
•unicellular (yeast), filamentous, or both (=dimorphic)
•Hypha (pl. hyphae) is the basic “cellular” unit in
filamentous fungi; they may be septate or coenocytic
(aseptate); collectively a mycelium
•limited tissue differentiation and division of labor
•somatic & reproductive structures
•plectenchyma: all organized fungal tissue, somatic &
reproductive

4. Nuclear Status
•Eukaryotic; uni, bi- or multinucleate
•Haploid, diploid (less frequent)
•Monokaryon
(1 nucleus per hyphal compartment)
•Dikaryon
(2 nuclei per hyphal compartment)

•Homokaryotic
•Heterokaryotic

5. •Mitosis
–intranuclear: nuclear membrane doesn't
breakdown during mitosis
–centric in flagellated forms; typical centrioles
of eukaryotes
–noncentric in nonflagellated forms; possess
spindle pole bodies (SPBs); differ from
centrioles in lacking microtubular component

6. Organelles
•typical eukaryote assemblage of organelles
+ fungal specific ones
•mitochondria
•endoplasmic reticulum
•Golgi equivalents
single cisternal elements
•vacuoles
•microbodies
funx in fatty acid degradation,
N metabolism

7. Cell Wall
•well defined
•chitin
1-4 n-acetyal glucosamine
-glucans
polymers of glucose
1-3 glucose
•cellulose in some
1-4 glucose
chitin-glucans
Chitin
Cellulose
 1-3 glucan

8. •fungal specific organelles involved in cell wall growth
Spitzenkorper
associated with growing hyphal tips in septate fungi
chitosome
microvesicles transporting chitin synthases to growing cell wall

9. Nutrition
•Heterotrophic
•Secrete extracellular enzymes
•Absorptive nutrition
•Saprobes: decay dead organic matter
•pathogens: biotroph, necrotroph
•symbionts: parasites - commensals - mutualists

10. Spores - a minute propagative unit functioning as a seed, but
differing from it in that a spore does not contain a preformed
embryo
Fruiting body - any complex fungal structure that contains or
bears spores; a sporocarp

11. Reproduction
•Sexual reproduction: spores meiotically derived nuclei
•Homothallic (selfing)
•Heterothallic (outcrossing)
•Monoecious or dioecious
•Genetic mating system
–MAT loci
–1 to hundreds of “sexes”
•Asexual reproduction
–Spores with mitotically derived nuclei

12. Misc.
•Life cycle: simple to complex; wide variety
•Sporocarps: microscopic or macroscopic,
limited tissue differientiation
•Habitat: ubiquitous
•Studied by mycologists!!!!!!

13. What are fungi?
•Eukaryotic, spore-bearing, heterotrophic
organisms that produce extracelluar
enzymes and absorb their nutrition.

14. Fungi vs. "fungi"
•Based on the phenotypic definitions or traits
attributed to fungi, fungi do not comprise a
single monophyletic group of organisms
•more than one evolutionary origin
•not all "fungi" are members of the Kingdom
Fungi

15. FUNGI (e.g., mushrooms, yeasts)
MICROSPORIDIA
METAZOA (Animals)
DICTYOSTELIDAE
MYXOGASTRIDAE
LOBOSA
ANGIOSPERMAE (Green Plants)
CHLOROPHYCEAE
RHODOPHYTA
GLAUCOPHYTA
OOMYCETES
PHAEOPHYCEAE (Brown algae)
CILIOPHORA
APICOMPLEXA
KINETOPLASTIDA
EUGLENOIDEA
ACRASIDAE
VAHLKAMPFIIDAE
PARABASALLA
DIPLOMONADIDA
Slime molds
Phylogeny
Of
Eukaryotes
(some water molds
Sudden Oak Death)
based on
DNA
sequence
data

16. Some characters that separate the
the Kingdom Fungi from “protistan fungi”

Kingdom Fungi Protistan fungi
mitochondria: cristae flattened cristae tubular
motile cells: no motile cells or motile cells with anterior
posterior flagellum or lateral
heterokont flagella
cell wall
carbohydrate: glucans, chitin glucans, cellulose

lysine biosynthesis:alpha-aminoadepic acid (AAA) diaminopimelic (DAP)
storage compoundglycogen mycolaminarins
sterols ergosterol fucosterol
Phyla: Chytridiomycota Oomycota
(emphasized Zygomycota Myxomycota
in class) Glomeromycota Dictyosteliomycota
Basidiomycota
Ascomycota

17. General characteristics of the Phyla of the Kingdom Fungi
basal lineages

Chytridiomycota: (800)
•unicellular to mycelial (coenocytic)
•zoospore with single posterior whiplash flagellum
•aquatic & terrestrial
•no sporocarp production
Zygomycota: (1000)
•generally coenocytic mycelium
•production of zygosporangia & zygospores
•no sporocarp production
Glomeromycota: (200)
•formerly part of Zygomycota
•coenocytic mycelium
•no known sexual reproduction
•arbuscular mycorrhizae (Glomerales)
•no sporocarp production

18. Basidiomycota: (22500)
•septate mycelium
•clamp connections
•complex dolipore septa
•dikaryotic, haploid mycelium
•production of exospores (basidiospores) on a basidium
•production of complex sporocarps
Ascomycota: (35000)
•septate mycelium
•simple septa
•monokaryotic, haploid mycelium
•production of endospores (ascospores)
in an ascus
•production of complex sporocarps
•often dominant asexual reproduction

19. Chytridiomycota
+
Zygomycota
Ascomycota
Basidiomycota
Glomeromycota
Chytridiomycota
Phylogeny of Kingdom Fungi
Regularly septate
hyphae
Multiple losses
of flagellum
X
X
chitin*
glycogen*
mito cristae*
ergosterol
post smooth flagellum*
*share with animals asci + ascospores
basidia + basidiospores
dolipore + clamp connections

20. http://ocid.nacse.org/research/aftol/

21. Silurian 440 hypha, spores ?Ascomycota
Devonian 410 wood decay Basidiomycota
mycorrhizae Glomeromycota
zoosporangia Chytridiomycota
Carboniferous360 zygospores Zygomycota
clamp connections Basidiomycota
?fruit bodies
Permian 286 white rot Basidiomycota
Triassic 245 wood decay Basidiomycota
mycorrhizae Glomeromycota
Jurassic 208 shelf fungus Basidiomycota
Cretaceous 144 rusts Basidiomycota
polypores
conidia Ascomycota
Tertiary 65 extant morphologies
Fossil Record of Kingdom Fungi - How old are fungi?

22. Hymenomycetes
mushrooms, shelf fungi
jelly fungi, coral
crusts, puffballs
Ustilaginomycetes
smuts
Urediniomycetes
rusts, marine yeasts
crusts
3 Major Clades - Classes - of the Basidiomycota

23. Kingdom - Fungi
Phylum - Basidiomycota
Class - Hymenomycetes
Order - Agaricales
Family - Amanitaceae
Genus - Amanita
Species - A. muscaria
Amanita muscaria
Nomenclature

24. Introductory Mycology BOT 461/561
http://ocid.nacse.org/classroom/fungi/bot461/