Quiz 2 - Hanson - Intro To Mycology Flashcards
What is mycology?
Study of yeasts and molds
T/F - Fungi are eukaryotes.
TRUE
*Ubiquitous in nature
What is in the cell walls of yeasts and molds?
CHITIN
*Also beta-glucans
What is ergosterol?
A lot like cholesterol, but different, and we can target that with drugs. Gives the cell membrane rigidity
Contrast yeasts vs. molds
Yeasts -Single cells -Culture is: —Single colonies —Creamy, mucoid —FACULTATIVE ANAEROBES
Molds -Multicellular, filamentous -Hyphae —These can interweave to form a mycelium mat -Culture is: —Fuzzy, velvety —OBLIGATE AEROBES
What is the micro term for a bud of a yeast?
Blastoconidia
What are chains of blastoconidia called?
Pseudohyphae (yeast)
*These have distinctive indents, or pinches, in them, not a continuous tube
What yeast can make true hyphae?
Candida albicans
What is a germ tube?
A true hyphael element
True hyphae have two divisions. Name them.
Septate- Aspergillus - look like pseudohyphae, but are true hyphae. They are not tapered at the end of the tube
Nonseptate/Aseptate - Zygomycete - Germ tube
What is the asexual state of yeasts and molds called?
Anamorph
*Mitotic division of a haploid nucleus - budding for yeasts, conidia or separation of hyphael elements
What is the sexual state of yeasts/molds called?
Telomorph
*Diploid nucleus divides by meiosis - Haploid nuclei of donor and recipient fertile cells fuse for yeasts, for molds, spores are used
What does dimorphism fungi mean?
Give 3 important species that exhibit dimorphism.
Group of geographically restricted pathogens that exist as a mold at RT and a yeast at BT
Blastomyces dermatitidis
Coccidiodes immitis/posadasii
Histoplasma capsulatum/duboisii
What does opportunistic fungi mean?
Only cause disease in compromised hosts
Give 5 risk factors for yeast/fungal infections.
Immunocompromised -organs recipients -HIV -Autoimmune disease Premature infants Critically ill and hospitalized patients Travelers and residents of endemic areas Direct contact with animals or infected materials
What are three methods to ID specimens?
Direct microscopy - Fast, cheap
Culture - Gold standard from sterile body site
Histopathology - Gold standard for invasive disease
If you have a pure culture, what are 2 methods used for IDing?
Proteomic ID - MALDITOFMS - Matrix assisted laser desorption ionization time of flight mass spectrometry
Targeted gene sequencing
What are the 2 most common candida types?
Albicans, glabrata
*Thrush, vaginitis, esophagitis, etc.
**GLABRATA RESISTANT TO FLUCONAZOLE
T/F - Rhinocerebral zygomycosis is angioinvasive.
TRUE - It follows blood vessels. Lady with large mass and pain in her maxillary sinus
