Concepts in microbiology - fungi Flashcards
What does mycology mean?
study of fungi
What are medical mycologists?
scientists who study pathogenic fungi
What is mycotoxicology?
the study of fungal toxins and their effects
What are mycoses (s. mycosis)?
diseases caused by fungi
Which domain are fungi a part of?
eukaryota
What is the variation in size and complexity of fungi?
Can be microscopic single cell yeasts, macroscopic mushrooms, humungous fungus
Beneficial impacts of mycology
fungi are decomposers, used as industrial fermenters (foods, beverages, and steroids, antibiotics, drugs), used to model eukaryotes in research
Detrimental impact of fungi
cause of many animal and plant diseases
How is DNA in fungi arranged?
fungi is eukaryotic so DNA is arranged into chromosomes
Example of fungi having different morphological states
hyphae (can be 100s times the biovolume of a different fungi)
Examples of eukaryotic microbes
yeasts and molds
Are yeasts multi or unicellular?
unicellular
How do yeasts reproduce?
Budding (a form of asexual reproduction in which nucleus divides by mitosis)
What colour do yeasts appear in a gram stain?
Blue/purple because they are gram positive (due to cell wall)
How do fungi gain their nutrients?
they are heterotrophs
Use of yeasts
ferment beer, wine, bread
How are yeasts grown in vitro?
25-37C, acidic conditions, enriched with Sabouraud’s dextrose, potato dextrose, nutrients
Are molds uni or multicellular?
multicellular
How can molds reproduce?
Sexual or asexual (sporulation) reproduction
Usual habitat for molds
dark/moist conditions
How do molds grow?
grow in multicellular, fibre-like structures called hyphae
Components of the cell wall of fungi
chitin, glucans, glycoproteins
What is the most abundant component of the fungi cell wall?
Glucans
Components of fungi cell membrane
phospholipids and ergosterol (equivalent to cholesterol)
Which component of the fungi cell membrane is a target for some antifungals?
ergosterol
Why is the fungi cell wall a key virulence factor?
Cell wall can be reorganised
Dimorphic meaning
ability to have different shape/phenotype/morphism
Examples of single cell fungi demonstrating dimorphism
spores, yeasts, pseudohyphae, hyphae, filaments
How many people do fungal infections kill annually?
2 - 3.75 million
Examples of fungi on WHO’s priority list
invasive candidiasis, invasive aspergillosis, cryptococcosis, cryptococcal meningitis, crytococcaemia, azole and multidrug resistance fungi (Candida auris)
Scale of fungal infection severity
superficial, cutaneous, subcutaneous, opportunistic, invasive