microbio- yeasts

true

true or false: yeasts are eukaryotic and unicellular

eukaryotic

are yeasts prokaryotic or eukaryotic?

blastoconidia

what type of conidia is produced asexually by yeasts?

false- yeasts do not have hyphae at all

true or false: yeasts have aseptate hyphae

Candida, Cryptococcus, Malassezia

what are the 3 important genuses of yeasts?

Candida albicans

what is the important species in the genus Candida?

Cryptococcus neoformans

what is the important species in the genus Cryptococcus?

Malassezia pachydermatis

what is the important species in the genus Malassezia?

chlamydo-, cornmeal

the genus Candida grows ______spores on _______agar

chlamydospores

what type of spores are produced by the genus Candida when isolated on cornmeal agar?

Candida

which yeast genus is related to immunosuppression in both humans and animals?

no

do we commonly find Candida in the environment?

Cryptococcus

which genus produces a large mucopolysaccharide capsule?

localized granulomas or disseminated disease (DIC)

Cryptococcus causes what issues in cats, dogs, horses, and cattle?

Cryptococcus

which genus is found in the environment and uses creatine from bird droppings?

canine seborrhoeic dermatitis and otitis externia

the genus Malassezia is associated with what diseases?

the skin

Malassezia affects what part of the animal?

Malassezia

which genus affects the skin of mammals and birds?

Malassezia

which genus is associated with canine seborrhoeic dermatitis and otitis externa?

37, SDA

Candida albicans grows aerobically at ______ degrees on _______

Candida albicans

which species are polymorphic- appear as pseudohyphae or hyphae in animal tissues?

mucous membranes of the oral cavity, GI tract, and urogenital tract

what part of the animal does Candida albicans commonly affect?

-immunodeficiency
-corticosteroid therapy
-prolonged administration of antibody

what factors predispose an animal to a Candida albicans infection?

hematogenous spread- hyphae/pseudohyphae invade the blood vessels and can cause systemic lesions

how does Candida albicans spread throughout the body?

adhesion to host cell proteins

what do the surface proteins of Candida albicans allow for?

Candida albicans

which species has surface structures than can bind proteins and complement components for protection?

tissue invasion

Candida albicans produce phospholipases (enzymes) to aid __________

phenotypic switching- it avoids the immune response

what is the advantage of Candida albicans' ability to transform into hyphae or psedohyphae?

Candida albicans

which species infects the mucous membranes of the oral cavity, GI tract, and urogenital tract?

Candida albicans

which species exhibits polymorphism, and changes to hyphae/pseudohyphae inside of animal tissues?

Candida albicans

this mycosis is caused by what species?

cotton swab

what is the appropriate sample for this?

it can be isolated, but not differentiated from other species/ to be able to differentiate yeast colonies, we need to use a selective indicator media

what is the problem with isolating yeasts on SDA?

blue/green

on a selective indicator media, Candida albicans appear what color?

Candida albicans

which species can produce these 3 forms?

pseudohyphae with chlamydospores and blastoconidia

when isolated on cornmeal agar, Candida albicans produces what?

germ tubes

what is produced by Candida albicans when isolated in serum?

Candida albicans

which species produces germ tubes when isolated in serum?

Candida albicans

what species?

cornmeal agar (because there is pseudohyphae with chlamydospores and blastoconidia)

what medium was this Candida albicans isolated on?

Candida albicans, serum at 37 degrees (produces germ tubes)

what species and what medium is used for isolation?

Cryptococcus neoformans

what species of Cryoptococcus do we study?

mucopolysaccharide capsule

Cryptococcus neoformans produces a thick ____________ around the yeast

Cryptococcus neoformans because there is a thick mucopolysaccharide capsule around the yeast

which species?

it is a part of the normal microbiota of the animal, but certain conditions can cause an overgrowth

how is an animal infected by Candida albicans?

Candida albicans and Malassezia pachydermatis

which species is normally existing in the animal, but can cause an infection if certain conditions cause an overgrowth?

spore (blastoconidia) inhalation

how is an animal infected by Cryptococcus neoformans?

Cryptococcus neoformans

which species can germinate throughout the entire respiratory tract?

Cryptococcus neoformans

which species lives in the environment in bird droppings?

in the environment in bird droppings

where does Cryptococcus neoformans usually live?

they are normal microbiota in the mucous membranes of animals

where does Candida albicans normally live?

granulomas- tumor-like myxomatous masses

what lesions does Cryptococcus neoformans cause?

the brain, meninges, and bone

a Cryptococcus neoformans infection can spread from the respiratory tract to ____________

it resists phagocytosis

what is the function of the mucoid capsule of Cryptococcus neoformans?

Body temperature

at what temperature do Cryptococcus neoformans grow?

Cryptococcus neoformans

which species produces phenoloxidase, which allows melanin accumulation in the cell wall, providing protection from the fungus against free radicals?

it produces phenoloxidase, which allows melanin accumulation in the cell wall

how is Cryptococcus neoformans protected from free radicals?

Cryptococcus neoformans

this represents the route of which yeast?

no

do Cryptococcus neoformans commonly infect domestic animals?

nose swab

infection by Cryptococcus neoformans. what sample would we appropriate?

-exudates (fluids that leak from blood vessels)
-cerebrospinal fluid (if there are neurological signs)
-biopsy
-post mortem tissues

what are suitable specimens to collect from an animal infected by Cryptococcus neoformans?

yes, very easily- so it is necessary to isolate using a safety cabinet

can humans be infected by Cryptococcus neoformans?

Cryptococcus neoformans

what species is this, isolated on bird seed agar?

bird seed

Cryptococcus neoformans produces brown/orange colonies on __________ agar

Malassezia pachydermatis

what is the important yeast species in the genus Malassezia?

monopolar budding

Malassezia pachydermatis reproduce by......

Malassezia pachydermatis

which species reproduces by monopolar budding?

Malassezia pachydermatis and Candida albicans

which species are part of the normal microbiota of the animal, so cause infection only when external factors trigger an overgrowth?

it is a normal microbiota, so needs external factors to cause an overgrowth. this overgrowth is usually associated with immunosuppression and other predisposing factors that alter the microclimate of the skin or ear canal

how does Malassezia pachydermatis cause an infection in the animal?

Malassezia pachydermatis

which species commonly infects the skin and/or ear canal of the animal?

skin of mammals and birds- areas rich in sebacious glands (anal region, external ear canal, lips, interdigital skin)

the normal habitat of Malassezia pachydermatis is.........

Malassezia pachydermatis

which species lives in the areas of the animal that are high in sebacious glands?

Malassezia pachydermatis

which species?

Malassezia pachydermatis

otitis externa and dermatitis are the common clinical conditions of what yeast species?

wax overproduction and enzymes that damage the mucosa- because they cause inflammatory changes, inflammatory exudate, and necrotic debris accumulation in the ear canal

otitis externa is caused by Malassezia pachydermatis when these conditions are present:

Malassezia pachydermatis

these clinical signs are common of what yeast infection?

it is the excessive sebacious secretion caused by the lipases produced by yeast cells. typical of Malassezia pachydermatis

what is seborrheic dermatitis? what yeast species typically causes this?

canine seborrheic dermatitis, caused by Malassezia pachydermatis, use a skin scraping sample

what is this condition called? what yeast species causes it? what sample would we take?

canine otitis externa, caused byMalassezia pachydermatis, use an ear canal swab

what is this condition called? what yeast species causes it? what sample would we take?

Malassezia pachydermatis, skin scraping or adhesive tape sample

feline chin acne is a common clinical sign of what yeast infection? what sample would we take?

-exudate from ear canals and impression smears
-rigorous skin swabbing
-superficial skin scraping
-biopsy (for severe subcutaneous dematitis)

what specimens are appropriate for the diagnosis of an Malassezia pachydermatis infection?

Malassezia pachydermatis

what species caused this infection?

Malassezia pachydermatis

what species?