Einführung in die Pilze: 1

Question 1

size of fungi

Answer 1

They are often invisible, and the single hyphae might be small (2
10 µm diameter), but Fungi represent the third biggest global biomass component (after plants and bacteria )

Question 2

Characteristics of fungi

Answer 2

(1) eukaryotic
(2) typically haploid genome
(3) typically grow as hyphae with apical growth; sometimes as yeast
(4) heterotrophic
(5) osmotrophic nutrient uptake
(6) cell wall primarily composed of chitin and glucans
(7) production of spores

Question 3

Phylogeny

Answer 3

groups:
1. slime molds
2. Oomycetes
3. true fungi

Question 4

haploidity

Answer 4

• sexual or asexual propagation
• sometimes morphologically very different
• sexua stages unknown for a vast number of fungi

Question 5

results of mitotic division

Answer 5

identical to parent= clones

Question 6

results of karyogamy & meiosis

Answer 6

non- identical to each parent through recombination

Question 7

yeast-like vs filamentous fungi

Answer 7

• dimorphism

- “yeast” just describes the morphology, not the phylogeny

Question 8

growth patterns of fungi

Answer 8

-apical growth
driving forces:
1)”birth of new material and autolysis of old material
2) actin cytoskeleton

• branching
• anastomosis (fusion)

The sum of the above leads to the mycelium formation

Question 9

What are hyphae

Answer 9

Hyphae are essentially tubes of indeterminate length
(but constant diameter) with a rigid wall, containing a
moving slug of protoplasm

Question 10

heterotrophic

Answer 10

Fungi, like
humans , need organically
bound carbon as energy source and
construction material“ ->
they are chemoorganotrophs

Question 11

osmotrophy

Answer 11

see sl. 22

Question 12

cell envelope characteristics

Answer 12

• plasma membrane
• periplasmic space
• cell wall
• (capsules, fimbriae..)

Question 13

cell wall characteristics

Answer 13

• fibrillar polymers
• embedded in matrix
• very dynamic

Question 14

functions of fungal cell wall & envelope

Answer 14

• osmotic protection
• UV protection (pigments)
• molecular sieve
• interaction with environment
• binding sites for enzymes (proteases, glycosidases etc.)

Question 15

cell wall organisation

Answer 15

see sl 25

Question 16

major fibrillar polymers in ascomycetes and basidiomycetes & details

Answer 16

• chitin
• β(1,3)-, β(1,6)-glucan
• glucan & chitin are produced at the plasma membrane (glucan synthase & chitin synthase)
• glycoproteins are delivered in vesicles

Question 17

structural representation of polymers

Answer 17

see sl 27, 28

Question 18

The „steady state “ model of hyphal tip growth

Answer 18

•viscoelastic properties of the wall
•new material flows outwards and backwards as more new
components are added
•progressive cross linking causes reduced flow

-cell wall formation is intimately bound to apical growth

Question 19

what particular substances can the cell wall have?

Answer 19

the cell wall can have important additional pigments, proteins or polysaccharides to
provide functionalities.

Examples:
->Pigments – e.g. melanin (UV-protectant; structural
strength, resistance to stresses,…)
->polysaccharides – e.g. pullulan (food additive for
film formation such as in breath fresheners)
->proteins – e.g. hydrophobins (aerial structures)

Question 20

fungal reproduction/spores

Answer 20

-Fungi have the ability to produce an enormous number of spores => abilities of fungi to produce great amounts of protein
& biomass in short time => useful for biotechnology

-spore production is also an important hallmark in the distinction of fungal phyla

Question 21

Ascomycota

Answer 21

-endogenous
spore formation in asci

•mating types:
-bipolar: usually a/A
(or α/a)

Question 22

Basidiomycota

Answer 22

-exogenous spore
formation from specialized hyphae:
basidia

•mating types
 -bipolar or
tetrapolar and
multiallelic
(=complicated but
increasing chance of
mating >>50%)

Question 23

7 major groups within “true” fungi

Answer 23

-opisthosporidia
-blastocladomycota
-chytridiomyceta
-zoopragomycota
-mucoromycota
-dikaryomycota
>ascomycotina
>basidiomycotina