Section 57 Fungal Classification, Structure, and Replication

Ascomycota

Ascomycota

Largest most diverse group of fungi that include cup fungi and several yeasts (e.g. Saccharomycetes). Can make conidia. 50% of known fungi and 80% of the medically relevant fungi are these

Basidiomycota (club fungi)

Typically environmental fungi (decomposers) with sexual spores borne externally on club-shaped structures called basidia (found on gills of mushrooms) or just the ends of hyphae - include Cryptococcus (opportunistic pathogen)

coenocytic hyphae

hyphae that contain no septa and appear as long, continuous cells with many nuclei

conidia

nearly ubiquitous asexual spores of fungi - often the source of fungal respiratory infections

cutaneous mycoses

fungal disease that affects hair, skin, and nails - metabolize keratin and cause diseases like athlete's foot and ringworm

thermal dimorphism

Fungi that grow as different forms based on different temperatures - common in pathogenic fungi "Yeast in the Beast" (e.g.body temp) vs filamentous fungi at room temp.

endemic mycoses

fungi prevalent in soil throughout certain geographic locations that are capable of causing infection in healthy hosts

Glomerulomycota (Murcomycetes)

Formerly zygomycetes - mucormycosis is a rare but serious respiratory fungal infection from immunocompromised individuals being exposed to the fungus in the environment (increase in cases post-COVID recovery)

mycoses

diseases caused by fungi

superficial mycoses

localized fungal infection - e.g. hair shafts and skin (dermatomycoses)

systemic mycoses

fungal infections that spread throughout the body of those infected - most are found in specific regions (e.g. endemic disease)

zygospores

a single-celled reproductive structure formed in sexual reproduction by some fungi; zygospores contain genetic information from two different mating types, - and +

heterotrophic

Organisms that obtain their nutrients or food from consuming other organisms.

chitin

A structural polysaccharide, consisting of amino sugar monomers, found in fungal cell walls and in the exoskeletons of arthropods.

immunocompromised

having an immune system incapable of responding normally and completely to a pathogen or disease

ergosterol

steroid-type protein found in the cell membrane of fungi; similar in configuration to adrenal hormones and testosterone

septate hyphae

hyphae whose cells are divided by walls

sporangia

Spore-producing structure in fungus