Fungi Flashcards

Flashcards covering various aspects of fungi, including introduction, diversity, growth, development, disease, and biotechnology.

Ubiquitous Fungi

Fungi are present everywhere and are widespread, especially in moist environments.

Hypha

The basic structural unit of a fungus, can be unicellular or multicellular.

Mycelial Network

A network of hyphae, which is crucial for fungal organization and success

Sexual Reproduction (Fungi)

Reproduction involving zygospores, ascospores, or basidiospores.

Asexual Reproduction (Fungi)

Reproduction involving conidia.

Fungal Cell Wall

The fungal cell wall provides protection from physical damage and interacts with the host's immune cells.

Fungal Nutritional Strategies

Nutritional strategies employed by fungi, including mutualism, parasitism and commensalism.

Saprotrophs

Fungi that decompose organic material.

Necrotrophs

Fungi that invade and kill host plant tissue rapidly, then live saprotrophically on the dead remains.

Biotrophs

Fungi found on or in living plants that do not kill their host plant rapidly.

Geomycology

Fungi mediate biogeochemical transformations in aquatic and terrestrial habitats, influencing rock and mineral transformations, element recycling, and more.

Lichens

A mutualistic symbiotic association between a fungus and a photosynthetic partner (algae or cyanobacteria).

Harmful Effects of Fungi

Fungi cause disease in plants, animals and other organisms, damage man-made materials and produce toxic metabolites.

Fungal Impact on Agriculture

Estimated annual crop loss worldwide caused by microbial diseases, a large majority of which are caused by fungi.

Exploitation of Fungi

Fungi can degrade lignin and cellulose and are used in the production of food, drinks and drugs.

Fungal Diversity Estimates

Fungal diversity estimates ranging from 0.005 million to 11.2 million species based on different studies and environments.

Amoebozoa

A group of fungi including slime molds.

Stramenopiles

A group of fungi including oomycota.

Taxonomic Ranks (Fungi)

Taxonomic ranks from Domain to Species, including Kingdom, Phylum, Class, Order, Family, Genus, and Species.

Anamorph

Asexual state of fungi.

Teleomorph

Sexual state of fungi.

Chytrids

A deprecated fungal phylum; now divided into Chytridiomycotina, Blastocladiomycota, and Neocallimastigomycota.

Zoosporangium

A key feature of chytrids, containing zoospores with a single posterior flagella.

Zoospores

Motile spores in chytrids that exhibit chemotaxis and encyst to produce resting spores.

Tripartite Mutualism

Partnership where chytrids, mammals and methanogens interact.

Batrachochytrium dendrobatidis

A chytrid species that poses a major threat to amphibians.

Zygomycota

A fungal group utilizing simple carbon sources and producing asexual spores in a sporangium; sexual spores are known as zygospores.

Glomerulomycota

Fungi forming arbuscular mycorrhizae and are obligate mutualistic biotrophs (cannot be grown in the lab!).

Ascomycota

Fungi with septate hyphae, producing sexual spores (ascospores) in asci.

Ascospores

Spores that are forcibly discharged.

Conidia

Asexual spores produced by conidiation

Basidiomycota

A phylum containing most of the macrofungi (mushrooms) and some basidiomycetous yeasts.

Basidiospores

Spores produced on basidia

Homothallism

Describes fungi with mycelium that is sexually self-fertile

Heterothallism

Describes fungi with mycelium that is sexually self-sterile requiring another mycelium of a different mating type for sexual reproduction to occur

Germination (Fungi)

Switching between isometric growth and polarized growth when germinating.

Coenocytic (aseptate) and Septate Hyphae

Hyphae that either lack or contain cross walls

Cellular Arrangement (Fungi)

A key factor for success with polarized hyphal tips and autotropism

Fungal Cell Wall

A unique organelle that helps maitain shape, stabilises internal osmotic conditions and acts as a scaffold

Septa

Specialized structures that permit regulated flow of materials, these can be perforate or imperforate.

Anastomosis

The process where hyphae fuse, allowing the formation of a complex interconnected network

Mycelium

The mass of hyphae that forms the body of a fungus.

Sporulation

Production of asexual spores.

Mating in Zygomycota

Cooperation between the positive and negative mating types.

Mating in filamentous Ascomycota

Dikaryotic hyphae, mycelium, ascus and ascospores all play a role in the process of

Mating of Saccharomyces cerevisiae

The mating process controlled by genetic locus with MAT genes.

Monokaryon

Uninucleate haploid form of fungi

Dikaryon

Binucleate haploid form of fungi.

Intended Learning Outcomes

The ability to describe fungal diversity and increase your 'myco-scrabble' skills

Magnaporthe oryzae (rice blast)

The most important fungal plant pathogen, can destroy 11-33% of rice crop per year.

Rice Blast Disease

A destructive disease in rice, can cause a loss of 11-18% yield per year.

Direct Penetration

Enzymatic activity and mechanical force are modes of

Criteria for a Fungus to be a Human Pathogen

To cause disease, fungi must be able to grow at or above host body temperature; reach internal tissues; lyse tissues and absorb their components and evade host immune defences.

Co-morbidities and fungal disease

Conditions that can influence susceptibility to fungal infections, such as infectious diseases, cystic fibrosis, diabetes, COPD or inherited immune deficiencies.

Diagnostic Techniques (Fungi)

Clinical examination of samples, culture of the organism, serology, antigen detection and molecular diagnostics are all

New Drugs in the Pipeline against Fungal Infections

Screening for fungal specific components and pathways as well as combination therapies.

Mycotoxins

The toxic secondary metabolites produced by fungi, that are carcinogenic.

Mycetisms

Mushroom poisoning involving fatalities or significant toxins

Amanita muscaria

Fatalities have been associated with eating

Mycorrhizae

Plant-Fungus mutualisms involved in extremely efficient scavenging of nitrogen and phosphorus.

Arbuscular mycorrhizae (VAM)

Mycorrhizae dominant amongst Glomeromycota.

Ectomycorrhizae

Associations between conifers that are important as saprotrophs and in mineral weathering.

Ericoid mycorrhizae

Type of fungi dominant in peat bogs, moorlands or heathlands.

Orchidaceous mycorrhizae

Transport of carbon compounds in the

Monotropoid mycorrhizae

Mycorrhizae can connect together different plants in a forest.

Fungi as global recyclers

Enzymes and metabolites are used to

Leave Litter Decomposition

Freshly fallen needles decompose slowly over a

Wood Decay

Fungi play a crucial role in

Cellulases

Cellulose breakdown is mediated by hydrolytic enzymes, which are produced by fungi

Lignin breakdown

Enzymes the produce ROS, that cause

Combined cellulose and lignin

breakdown produces a white rot.

Brown rot fungi

Fungi, that degrade cellulose but leave the lignin behind.

Agaricus spp

Mushroom cultivation involves straw compost pasteurization.

Quorn

Is 12% protein and contains all the essential amino acids for adults

Solid Fermentation Products

Hard Cheese! that is fermented with cheese.

Alcohol production

Beer, Wine, Sake produce

Fungi in industry

Wonder drugs produced by fungi such as, major antibiotic penicilin.

Antifungal drugs

Key antifungals target specific components of the

Antifungal drugs - Polyenes

Formerly though to bind to ergosterol in the fungal cell membrane and thus weakening it and causing leakage of K+ and Na+ ions .

Antifungal drugs - Azoles

First reported use by Woolly 1944; first commercial drug 1958 Now over 40 drugs that have a Variable spectrum of activity.

Antifungal Drugs - Allylamines

competitively inhibit squalene epoxidase, blocking conversion of squalene to lanosterol. Terbinafine is also active mostly used as a topical application

Antifungal drugs - Echinocandins

inhibit the synthesis of β-glucan in the fungal cell wall via noncompetitive inhibition of the enzyme 1,3-β glucan synthase • Caspofungin, micafungin and anidulafungin are semisynthetic derivatives • Fungicidal against some yeasts including most species of Candida; but not Cryptococcus, Trichosporon or Rhodotorula

Antifungal drugs - Flucytosine

also known as 5-fluorocytosine (5-FC) was first made in 1957Active towards susceptible strains of Candida or Cryptococcus neoformans.

Molecular Basis of Resistance

Resistance arising via point mutations in the target gene FCY1, and is common in Candida spp