INTRO TO MYCOLOGY Flashcards
Study of fungus
mycology
T/F: Fungi are eukaryotic
True
Cell structure of fungi
chitin
Difference of fungus to plants
Lack of chlorophyll and must absorb nutrients from the environment
Fungi reproduction process
Budding; Fragmentation; Spore release (sexual/asexual)
Unicellular with round nucleus and can be used in beverage preparation
Yeast
Reproduction process of yeast
BB: budding and binary fission
Multicellular, filamentous microorganism and contains hyphae. grows best at 30 degree celsius
Molds
Molds are reproduced by ________?
sexually or asexually and spread through spores
2 types of HYPHAE
Hyaline (moniliaceous) hyphae & Phaeiod (dermatiaceous) hyphae
Non pigmented or lightly pigmented hyphae
Hyaline (moniliaceous) hyphae
Darkly pigmented hyphae
Phaeiod (dermatiaceous) hyphae
stains used at hyaline and phaeiod hyphae
Gomori methylene stain & Fontana-Masson stain
Stain melanin causing phaeiod hyphae to appear brown and hyaline hyphae stain pink to red
Fontana-Masson stain
Ability of some fungi to exist in two forms dependent on the growth condition; includes mold phase and yeast or spherule phase
Dimorphic Fungi
phase seen in vivo or when organism is grown at 37 degree celsius
Yeast or tissue state
Phase seen when organism is grown at room temp (22-25 Celsius) in ambient air condition
Mold phase
Have both yeast and mold forms in the same culture
Polymorphic fungi
example of polymorphic fungi
Exophiala spp
Rapidly growing organisms normally found in the soil; produce profuse gray to white, aerial mycelium and characterized by the presence of hyaline, sparsely septate hyphae.
Glomeromycota
Genera of Glomeromycota
Mucor, Rhizomucor, Rhizopus
Reproduction process of Glomeromycota
Asexually reproduction ((+) sporangiopores
characterized by production of sexual spores known as ascospores
Ascomycota
Ascospores are formed within a saclike structure known as____________?
Ascus
Organism exist in a vegetative trophic form that reproduces asexually by binary fission
Pneumocystidomycetes
Contains the ascomycetous yeasts, which are characterized
by vegetative yeast cells that proliferate by budding or fission
Have an anamorphic stage belonging to the genus Candida
SACCHAROMYCETES
Sexual reproduction leads to the formation of a thin-walled sac
(ascus) that contains haploid ascospores
EUROTIOMYCETES
Have clamp connections occur at the septations in the vegetative
hyphae and are easily visible with light microscopy
BASIDIOMYCOTA
Cryptococcus, Malassezia, and Trichosporon
BASIDIOMYCOTA
Examples of microspora
Anncaliia Encephalitozoon,
Endoreticulatus Enterocytozoon Nosema, Pleistophora Vittaforma Tubulinosema and Trachipleistophora
Obligate intracellular, unicellular, spore forming eukaryotes
MICROSPORA
The superficial mycoses concentrate only on the
Stratum corneum layer
Predisposing factors for superficial mycoses infection
Humidity
Immunosuppression
Poor hygiene
Causes tinea versicolor
Malassezia furfur
Hyper or hypopigmentation of the skin; Lesions are well demarcated; with Fawn-colored macules
tinea versicolor
diagnosis of tinea versicolor
Skin scrapings in a potassium hydroxide (KOH)
preparation or (+) yellow fluorescence with a
Wood’s lamp on examination.
Malassezia furfur appearance in culture colonies
are cream-colored, moist, and smooth.
appearance of Malassezia furfur in direct microscopy
Spaghetti and meatballs fungus
Causative agent of Black Piedra (Infection on the hairs of the scalp)
Piedraia hortae
Diagnosis of black piedra
Hair with Hard Black Nodules; direct microscopy - Thick-walled rhomboid cells containing ascospores are seen.
How many ascospores are within one asci
eight
Cultured use in diagnosis of black piedra
Sabouraud dextrose agar (slow grower)
Part of the normal skin biota and causative agent of White piedra
Trichosporon spp.
Most fatal Trichosporon spp.
Trichosporon asahaii
Trichosporon spp. can cause meningitis.
Trichosporon mucoides
Direct microscopy of trichosporon spp. (white piedra)
(+) Arthrospores, hyphae and blastoconcidia
Tinea nigra (brown to black non-scaly macules that
occur on the palms and soles) Chronic superficial fungal infection of the palms and soles caused by _________?
Exophiala / Hortaea werneckii
Direct microscopy of hortaea werneckii
(+) septate, pigmented hyphal elements and budding cells
Fungal diseases of the keratinized tissues of humans
DERMATOMYCOSES
Tinea capitis
head
tinea favosa
head (distinctive pathology)
Tinea barbae
beard
Tinea corporis
body (glabrous skin)
tinea mannum
hand
tinea unguium
nails
tinea cruris
groin
Tinea pedia
feet
tinea imbricate
body (distinctive lesion)
Most cases are associated with gardening, particularly with
exposure to rose thorns (rose handler’s disease) and
sphagnum moss.
Sporothrix schenckii
Most commonly presentation of Sporothrix schenckii
Lymphocutaneous sporotrichosis. (+) nodular and ulcerative lesion along the lymph channels
Sporothrix schenckii is a dimorphic fungus thus have yeast phase and mold phase. What are the morphology of these fungus at yeast and mold phase?
Yeast phase: small, cigar-shaped
Mold phase: thin, delicate hyphae bearing conidia
developing in a rosette pattern.
Infections that affect internal organs or deep tissues of
the body.
SYSTEMIC MYCOSES
initial site of infection of systemic mycoses is the _______?
lungs
2 drugs inhibits bacterial growth added to SDA
Cycloheximide and Chloramphenicol
At what pH did the bacterial growth inhibit by cycloheximide and chloramphenicol
pH 5.6
at pH 5.6 bacteria inhibited by chloramphenicol and cycloheximide except with _______________ & ____________?
Histoplasma and Nocardia spp.
media used for Histoplasma and Nocardia spp.
BRAIN HEART INFUSION (BHI) BROTH & CORNMEAL TWEEN AGAR
Used for observation of vaginal specimens.
SALINE WET MOUNT
Kills bacterial organism.
Phenol
Preserves fungal structures.
Lactic acid
Stains the chitin.
Cotton blue stain