Microsporidia, Blastocladiomycota, Neocallimastigomycota Flashcards
What are microsporidia?
single-celled animal parasites
What major organelle that most eukaryotes have do Microsporidia lack? what do they have instead?
they do not have mitochondria
instead they have mitosomes
What lifestyles do Microsporidia have?
animal endoparasites
Where do microsporidia live?
usually in the GI tract of animals but spores can exist outside of host
Do Microsporidia typically exhibit both sexual and asexual reproduction?
no, sexual reproduction is rare
What are the major features of Microsporidia?
mitosomes instead of mitochondria
polar tubule coils in the sporoplasm and extends to penetrate host cells and push in the sporoplasm to carry contents and infect host
What are the economic or ecological implications of microsporidia?
they are emerging disease in humans
they parasitize livestock and other animals
they can be used as biocontrol agents
What is an example of Microsporidia?
Nosema apis - the honey bee parasite
Nosema locustae - a biocontrol for locusts and grasshoppers
Is it easy to culture Microsporidia?
no because they are obligate endoparasites of animals with specific host ranges
What are the defining features of Blastocladiomycota?
they produce motile zoospores and gametes with whiplash flagellum
cell walls have chitin
What environments do Blastocladiomycota inhabit?
water and wet soils for active growth
can persist in dry conditions as a resting sporangia
What lifestyles do Blastocladiomycota have?
saprophytes
parasites
pathogens of invertebrates and plants
What makes the Blastocladiomycota life cycle unique?
it can include alternation of haploid and diploid generations and different generations can have different hosts
sexual reproduction is also common
Describe the variations of Blastocladiomycota sporangia morphology
they can be formed from monocentric thalli (single zoosporangium) to polycentric thalli that are filamentous (multiple zoosporangia)
What are example species of Blastocladiomycota?
Allomyces arbusculus and Blastocladiella emersonii are model organisms
both saprobes in water or wet soil
What structures can Blastocladiomycota have that are unique?
rhizoids to anchor to substrates
pseudosepta (not true septa) in their hyphae
What is unique about the lifestyle of phylum Neocallimastigomycota?
they are obligate anaerobes that can exist only in the GI tract of mammalian herbivores - they provide a beneficial service by increasing cellulose digestion and nutrient uptake by the animal
How do Neocallimastigomycota break down cellulose and hemi-cellulose in their hosts’ bodies?
they form rhizomycelia to penetrate plant tissue consumed by host and excrete cellulases and other enzymes to break down lignin and cellulose
What is an example species of Neocallimastigomycota?
Neocallimatix frontalis
Do Neocallimastigomycota have sexual reproduction?
NO only asexual through the production of motile zoospores from sporangia
When do Neocallimastigomycota species release zoospores from their sporangia?
in response to food ingestion by the host
What major organelle that most other eukaryotes have do Neocallimastigomycota lack? what else? why? what do they have instead?
they don’t have mitochondria or other related structures for the oxidative phosphorylation path because they don’t use oxygen - they are completely anaerobic
they have hydrogenosomes instead for metabolism
What biotechnical applications do Neocallimastigomycota have?
probiotics for livestock health
expression of enzymes which break down complex carbon compounds can be useful in food, textile, paper, and biofuel industries
biofuel production - breakdown of lignocellulose and fermentation to produce ethanol
