MYCO | 1.1 Fungi & Tree of Life, 1.2 Brief History of Mycology

T/F: Fungi are heterotrophic eukaryotes with chitinaceous cell walls capable of photosynthesis

FALSE

Fungi are heterotrophic eukaryotes with chitinaceous cell walls incapable of photosynthesis

Hetetrotrophic eukaryotes with chitinaceous cell walls incapable of photosynthesis

Fungi

Fungi in Latin means _, but it has become a stand-in term for all members of the group

mushroom

T/F: Most fungi form mushrooms

FALSE

Why were slime molds and water molds previously considered fungi?

Due to their filamentous structures suspected to be hyphae-like

Fungi belong to the crown eukaryote group, derived from the

Last eukaryotic common ancestor (LECA)

T/F: Fungi size can range from individual cells (e.g., yeasts) to multicellular organisms

TRUE

The largest living organism on earth is a _

monoclonal fungus

Fungi are a diverse group of eukaryotes that include, _ (6), forming a kingdom under domain Eukarya

A) Yeasts
B) Rusts
C) Smuts
D) Mildews
E) Molds
F) Mushrooms

2 basic forms of fungi

1. Hyphal (filamentous)

2. Yeast

The evolutionary history of fungi reflects how they have been able to conquer many habitats through _

a diversity of forms

Various growth forms of fungi

• Aseptate hypha of Mucormucedo

All fungi have a base _ form in terms of their ultrastructure

yeast or hyphal

• Microscopic fungi consisting of solitary cells that reproduce by budding

• e.g., _

• Yeast

• Yeast cells of Saccharomyces cerevisiae

• Also called the filamentous or mold form of fungi

• Long filaments = hyphae, which grow by apical (tip) extension

• e.g.,

• Hyphal form

• Growing hypha of Aspergillus niger

T/F: Some fungi can alternate cell growth between yeast and filamentous forms, meaning they are dimorphic

TRUE

Yeasts are fungi because _

they possess features characterizing the Kingdom Fungi cesaf

• Chitin in cell walls

• Extracellular digestion

• Saprophytic nutrition

• Asexual reproduction

• Food stored as glycogen

Several fungi grow as _, rather than as hyphae

budding uninucleate yeasts

Yeasts are not different from hyphal fungi but represent a _

different growth form adapted to nutrient-rich environments

Fungus-like organisms such as _ (2) do not belong to kingdom Fungi but are often called fungi as well

G) Slime molds

H) Water molds

4 commonalities of members of Kingdom Fungi

hcec

• Heterotrophic

• Chitin in cell walls

• Enzyme secretion

• Cannot photosynthesize

T/F: Yeasts are not different from hyphal fungi but represent a different growth form adapted to nutrient-poor environments

FALSE

Yeasts are not different form hyphal fungi but represent a different growth form adapted to nutrient-rich environments

Fungi share a common protozoan ancestor with the _ they diverged from

animals

T/F: Choanoflagellates are classified under Kingdom Animalia

FALSE

Protista; Opisthokonta

T/F: All true fungi have a range of features that separate them from other organisms and serve to define the Kingdom Mycota (Eumycota)

TRUE

6 characteristic features of fungi

euhychi hehap rep

1. Possess common eukaryotic features

   1. Membrane-bound nucleus with several chromosomes

   2. Membrane-bound organelles

   3. DNA with introns

   4. Membranes with sterols

   5. 80S ribosomes

   6. Cytoplasmic streaming

2. Composed of hyphal filaments with apical growth

   1. Hyphae branch repeatedly behind their tips, giving rise to mycelial network (mycelium)

   2. Some fungi (e.g., yeasts) are single-celled and grow by budding

   3. Some are dimorphic

3. Unique cell wall

   1. Little to no cellulose

   2. Composed of chitin and glucans (glucose polymers) with associated proteins

   3. pcsm

      1. Plasma membrane = ergosterol + B-1,3-glucan synthase

      2. Chitin

      3. Sugar = B-1,6- and B-1,3-glucan

      4. Mannoproteins = glycoproteins

4. Heterotrophic

   1. Need pre-formed organic materials to survive

   2. Since they cannot engulf food molecules, they absorb soluble nutrients

   3. Enzyme secretion from hyphal tips is very common to degrade various materials (e.g., enzyme crystals in detergent)

5. Haploid nuclei

   1. Major difference from other eukaryotes & fungal hyphae with several nuclei is their haploid genome in their fungal nucleus

      1. Some fungi spend significant portion of their life cycle in haploid state (with haploid nuclei), i.e., 1 set of chromosomes

   2. Some yeasts are diploid

   3. Has major implications on fungal genetics

      1. Mutations are immediately expressed since there are no masking effects of a second allele, as what happens in a diploid organism

      2. Genetic adaptation and evolution would be more rapid

6. Reproduction (spores)

   1. Can reproduce sexually and asexually

   2. Reproduction typically uses spores, which are also used for dormancy and as tools for dispersion

   3. Reproductive strategies of different taxa can be very unique

T/F: More often than not, eukaryotic cells are diploid

TRUE

Except haploid gametes (e.g., sperm & egg cells)

Implications to being a diploid organism vs. haploid organism

• Diploid

  • Genetic diversity

    • Having 2 sets of chromosomes would allow for genetic recombination during meiosis; this shuffling of genetic material increases genetic diversity, which is crucial for adaptation and evolution in changing environments

  • Buffer against mutations (recessive alleles masking effect)

    • Having 2 sets of chromosomes would mean that deleterious mutations in 1 allele can be compensated by functional allele in the other, reducing likelihood of organisms expressing harmful traits and contributing to their overall fitness

• Haploid

  • Reduced energy cost

    • Having only 1 set of chromosomes means having a smaller amount of genetic material to replicate, repair, and segregate during cell division, allowing for faster growth rate and reduced energy costs

  • Direct expression of mutation

    • All alleles are expressed since there is no second allele to mask the effects → immediate expression of deleterious/beneficial mutations

Fungal characteristic/feature

• Need pre-formed organic materials to survive

• Since they cannot engulf food molecules, they absorb soluble nutrients

• Secretion of enzymes from their hyphal tips is a very common way to degrade various materials

Heterotrophic

Fungal enzymes are generally more stable than bacterial enzymes as detergent due to their _

heterotrophy, i.e., need to secrete substances to degrade materials

Fungal characteristic/feature

• Hyphae branch repeatedly behind the tips, giving rise to mycelial network (mycelium)

• But some fungi are single-celled and thus grow by budding, e.g., yeasts

• Some are dimorphic

Hyphal filaments with apical growth

Fungal characteristic/feature

• Can be a sexual or asexual process

• _ typically uses spores, which are also used for dormancy and as tools for dispersion

• _ strategies of different taxa can be very unique

Reproduction (spores)

Fungal characteristic/feature

• Little to no cellulose

• Has chitin and glucan (glucose polymers) with associated proteins instead

• Composition pcsm

  • Plasma membrane with ergosterol, B-1,3-glucan synthase

  • Chitin

  • Sugars = B-1,3,- ; B-1,6- ; B-1,4-glucan

  • Mannoproteins = glycoproteins

Chitinaceous cell wall

T/F: All fungi have chitin in their cell wall

FALSE

There has recently been a fungus discovered not to have chitin but possess euhy hehaprep = fungus

Fungal characteristic/feature

• Has

  • membrane-bound nucleus

  • membrane-bound organelles

  • DNA with introns (eukaryotic histones)

  • membranes with sterols

  • 80S ribosomes

  • cytoplasmic streaming

Possess common eukaryotic features

T/F: All fungi produce hyphae, even mushrooms.

FALSE

Yeasts are single-celled non-hyphal structures, but they possess euchi hehaprep = fungi

T/F: All yeasts cannot produce hyphae

FALSE

There are yeasts that can produce hyphae

Main structure fungi uses for growth and reproduction

Hyphae

T/F: Fungi includes phototrophic eukaryotes with rigid chitinaceous cell walls, forming single phylogenetic group

FALSE

Fungi includes nonphototrophic eukaryotes with rigid chitinaceous cell walls, forming single phylogenetic group

Fungal characteristic/feature

• Major difference from other eukaryotes and fungal hyphae with several nuclei is their _

• Some yeasts are diploid

• Have implications on fungal genetics, including _

• Haploid genome in the fungal nucleus

• Mutations are immediately expressed, given that there would be no masking effects of a second allele, as what happens in a diploid organism

• Genetic adaptations and evolutions would also be more rapid bc you’re dealing with only 1 set of chromosomes

T/F: Fungi reproduce primarily through spores

TRUE

T/F: All yeasts are haploid

FALSE

Some yeasts are diploid

Fungi share a common _ ancestor with the animals they diverged from

protozoan

Oldest fungi fossils are _ yo, but there is recent evidence of fungi-like microorganisms present in a 2.4 BYO _ (Bengtson et al. 2017)

• 460 - 455 myo

• Basalt stone (with filamentous hyphae-like structures)

T/F: No other living thing produces hyphae other than fungi

TRUE

But slime and water molds have filamentous hyphae-like structure

Oldest confirmed fungal fossils isolated from _ are similar to the modern-day _, which have flagella (water-dependence)

Chert (dark opaque rock consisting of silica) sedimentary rock Modern-day Chytridiomycota

Most basal group of fungi (oldest, most unchanged)

Chytridiomycota

Hallmark feature of Chytridiomycota

Flagella bc life evolved from water and thus need to utilize water medium to grow

T/F: Some fungi still have flagella; most don’t have, but there are spores that have flagella

TRUE

Stalked unicellular organism with collars (where collar is, there’s flagellum)

Choanoflagellates

_ anchors choanoflagellate, while _ is responsible for their motion

• Stalk

• Singular flagellum

Abundant evidence of fossil fungi associated with primitive land plants suggest _ due to fungi’s ability to enhance the uptake of mineral nutrients + water

coevolution

In present times, almost _% of living land plants have some kind of fungi associated with them to aid their metabolism and other activities

90%

Fungi, while classified as plants for a long time, are closer to animals and could have a common protozoan ancestor from the _ group, as evidenced by structure

Choanoflagellate

• Marine choanoflagellate = Monosiga brevicolis

• Zoospore of chytrid = Obelidium mucronatum

Egyptians consistently depicted fungi in _

hieroglyphics

Documentation of fungi in Egypt may be dated back to _

4500 BC

Rumor has it that Egyptians used fungi for rituals, specifically they used _ during their secret rites to attain an altered state and ascend to the realm of the gods

psychoactive mushrooms

What was true, however, is that Egyptians were among the earliest civilizations to realize the importance of _ for making bread, wine, and beer central to Egyptian culture (Ramses II)

yeasts

Biblically, the Israelites consume unleavened bread for festivals because these are considered _

“clean,” i.e., do not use any animals or yeasts and do not rise

What was true, however, is that Egyptians were among the earliest people to realize the importance of yeasts for making _ central to Egyptian culture

bread, wine, beer (1% or lower; now 6-10%)

T/F: Mycological illustrations have a rich history

TRUE

Oldest known mycological illustration was by the _ buried in 79 AD (eruption of Mt. Vesuvius)

Romans in Pompeii (fresco)

1st published fungal illustration was in a materia medica titled _

Ortus Sanitatis. De Herbis et Plantis […] in 1491

3 issues with historical mycological illustrations

npo

1. No fresh specimens

2. Primitive painting

3. Overactive imaginations

The origin of mushrooms fascinated the early human civilizations hwo believed in their _

spontaneous generation

Greeks, i.e., Pliny (23-79 AD), widely believed that truffles originated from a fluid generated by _

thunder mixing with heat, penetrating earth

Greeks believed that a mixture of _ resulted in generation of fungi

thm

thunder, heat, moisture (when in reality, fungal spores are triggered by humidity)

T/F: In the Philippines, fungi die out in wet season and bloom back in dry season

FALSE

Fungi generally thrive in wet and humid conditions since fungal spores are activated by humidity, making wet season the ideal time for fungal growth

_, i.e., _ (23-79 AD), widely believed that truffles originated from a fluid generated by thunder mixing with heat, penetrating Earth

Greeks, i.e., Pliny (23-79 AD) Naturalis Historia

A minority (of Greeks) believed that truffles were _ since they appeared after floods from Autumn rains (but these were too small to be seen)

seedborne

A minority (of Greeks) believed that truffles were seedborne since they appeared _ (important bc this was used later on by a taxonomist to categorize fungi into plants)

after floods from Autumn rains

T/F: Fungi is among the most mysterious living things because no one could figure out how they grew

TRUE

Early interest and speculation on fungi centered around _

spores first observed by Giambattista della Porta (1588)

3 competing spontaneous generation theories developed about origin of fungi

• Gaspard Bauhin (1560-1624)

  • “Mushrooms are neither plants, nor roots, flowers, or seeds prfs but only humidity coming from stdo the soil, the trees, dead wood and other rotten elements; their appearance and disappearance last approximately 7 days; they usually appear before thunder and rain”

• Friedrich Kasimir Medicus (1736-1808)

  • “Mushrooms are products of the jelly resulting from organic decay of leaves under the effect of heat and humidity”

• Traugott Frenzel (1746-1807)

  • “The shooting stars pull mushrooms from the earth”

Spontaneous generation theory on fungi origin

• Mushrooms are products of the jelly resulting from organic decay of leaves under the effect of heat and humidity

Friedrich Kasimir Medicus (1736-1808)

Spontaneous generation theory on fungi origin

• The shooting stars pull mushrooms from the earth

Traugott Frenzel (1746-1807)

Spontaneous generation theory on fungi origin

• Mushrooms are neither plants, nor roots, flowers, or seeds, but only humidity coming from the soil, the trees, dead wood and other rotten elements;

• their appearance and disappearance last approximately 7 days;

• they usually appear before thunder and rain

Gaspard Bauhin (1560-1624)

Giambattista della Porta’s description of fungi (1588)

“We picked up very thin seeds, small and black, hidden in the elongated veins that go from base to cap. The seeds that fall are always fertile and germinate.” [Phytognomonica 1588]

For the longest time, fungi were classified as _

imperfect, deficient plants

5 publications listing fungi as plants in 16th-18th century

1. De plantis = Andrea Cesalpino (1518-1603)

2. De mediis naturis in universe = Federico Cesi (1585-1630)

3. Elements de botanique = Joseph Pitton de Tournefort (1656-1708)

4. Lobelius = Matthias de l’Obel (1538-1616)

5. Catalogus plantarum sponte circa Gissam nascentium = Jakob Dillen (1684-1747)

4 common descriptions of Fungi in 16th to 18th century publications

Ramara sp. (Coral fungus), Peltigera sp. (Feckle pelt lichen)

• Fungi (and lichens) are in between inanimate objects and plants

• “Plants without seeds”

• Plantae imperfectae, deficientes, mutilate, inordinate idmi

• “Plants for which we know of neither flowers nor seeds”

Historical attempts at classifying fungi began as _

simple endeavors to understand their properties

• Classified fungi into edible/poisonous; lasted for 1500 years

• Published by Pedanius Dioscorides (1 AD)

Materia Medica

• He wrote Materia Medica (1 AD)

• Classified fungi into edible/poisonous; lasted for 1500 yrs

Pedanius Dioscorides

• Written by Pietro Antonio Micheli (1729)

• Foundation for systematic classification of mosses, grasses, fungi, Aspergillus + Botrytis, discovered spores

Nova Plantarum Genera

• He wrote Nova Plantarum Genera (1729)

• Foundation for systematic classification of mosses, grasses, fungi, Aspergillus + Botrytis, discovered spores

Pietro Antonio Micheli

Nova Plantarum Genera by Pietro Antonio Micheli (1729) provided the foundation for _

systematic classification of mosses, grasses, fungi, Aspergillus + Botrytis, discovered spores

Studying _ of fungi hinted at their differences from plants

detailed structures

2 proper mycological illustrations & microscopic descriptions made by Edmond & Charles Tulasne

• Fungi hypogaei (1851)

• Selecta Fungorum Carpologia (1861-1865)

3 discoveries by Edmond & Charles Tulasne from their illustrations of fungi (i.e., Fungi hypogaei, Selecta Fungorum Carpologia)

pdm

1. Can produce more than 1 spore type

2. Different life cycles

3. Mating between fungi

_ separated fungi from plants and other organisms

5-kingdom classification system by Whittaker (1969)

T/F: Whittaker argued in his 5-kingdom classification that Kingdom Fungi is separate not because of its microscopic structure but because of its ecological role

TRUE

Ecological role as multicellular decomposers (have saprophytic, detritivorous nature)

3 corrections in Whittaker’s 5-kingdom classification system

1. Fungi was separated based on their ecological role as “multicellular decomposers”

2. Fungi did not have photosynthetic ancestors

3. Cannot be placed in Plants or Protists

T/F: Fungi was separated in 5-kingdom classification system based on their ecological role as unicellular decomposers

FALSE

Fungi was separated in 5-kingdom classification system based on their ecological role as multicellular decomposers

T/F: Fungi have photosynthetic ancestors

FALSE

They are heterotrophic

T/F: Whittaker’s 5-kingdom classification system posited that Fungi cannot be placed in Plants or Protozoans

FALSE

Whittaker’s 5-kingdom classification system posited that Fungi cannot be placed in Plants or Protists

T/F: Fungi are eukaryotes, can be unicellular/multicellular, have cell walls, and are heterotrophic

TRUE

The traditional division of Kingdom Fungi consists of 5 major phyla established on the basis of _

reproduction or using molecular data

5 major phyla in traditional division of Kingdom Fungi

1. Chytridiomycota (Chytrids) (e.g., Batrachochytrium dendrobatidis)

2. Zygomycota (Conjugated fungi/bread molds) (e.g., Rhizopus) → Mucoromycetes, Zoopagomycetes

3. Glomeromycota (Endomycorrhizae) (e.g., Glomus)

4. Ascomycota (Sac fungi) (e.g., Saccharomyces)

5. Basidiomycota (Club fungi) (e.g., Amanita)

Fungal division/phyla

• Most primitive of true fungi (Eumycota)

• Mostly unicellular, but some form hyphae

• Gametes have flagella (water-dependence)

Chytridiomycota (Chytrids)