FUNGUS-LIKE PROTISTS

1
FUNGUS-LIKE PROTISTS

• Phylum Myxomycota
• Phylum Acrasiomycota
• Phylum Oomycota

http//www.nytimes.com/2011/10/04/science/04slime.
html?_r5pagewantedall
2
CHARACTERISTICS

• why fungus-like?
• appearance
• mode of nutrition
• with centrioles
• no chitin in cell walls
• non-photosynthetic
• 2-stage life cycle
• spore-bearing mold-like stage
• free-living amoeba-like stage

Stemonitis fusca
Comatricha typhoides
http//tywkiwdbi.blogspot.com/2011/11/slime-mold.h
tml, http//www.nationalgeographicstock.com/comp/0
4/442/1030283.jpg
3
Dominant state near rich sources of
food (phagocytic)
Fruiting body Spore-bearing structure
Cells aggregate into a slimy mass when food is
scarce and moves to a better location
http//www.nsf.gov/od/lpa/news/03/pr03106_images.h
tm
4
SLIME MOLDS

• Phylum Acrasiomycota
• Cellular slime molds

• Phylum Myxomycota
• Acellular slime molds

5
Phylum MyxomycotaAcellular or plasmodial slime
molds

• plasmodium
• large cytoplasmic mass (multinucleate)
• feeding stage
• unfavorable conditions fruiting
• sporangia spring up from plasmodium
• meiosis ? haploid spores? flagellated gametes
  ?diploid zygote (sexual reproduction) ?diploid
  amoeboid cells
• e.g. Physarum

http//biodidac.bio.uottawa.ca
6
http//home.sandiego.edu/gmorse/2009BIOL221/Study
_guide2/plasmodial.jpg
7
Physarum polycephalum
8
Comatricha typhoides
9
Lycolaga epinendrumwolfs milk
10
Stemonitis splendenschocolate tube slime
11
Arcyris denudatacarnival candy slime
12
Brefeldia maximatapioca slime
13
Tubifera ferruginosared raspberry slime
14
http//xkcd.com/877/ , http//www.uknature.co.uk/F
.septica.jpg, http//i55.tinypic.com/313k32b.jpg,
http//i56.tinypic.com/flly6t.jpg
15
Phylum Acrasiomycotacellular slime molds

• pseudoplasmodium
• separated by cell membranes
• cell aggregation
• slug-like form
• migrates to form fruiting body
• spores by mitosis
• e.g. Dictyostelium discoideum

16
(No Transcript)
17
Phylum Oomycotawater molds/downy mildew

• cellulosic cell wall
• live on organic matter in water, plant parasites
  on land
• hyphae ? finely-branched single-celled filaments
• coenocytic/aseptate ? no walls between cells
• motile spores

Phytophthora infestans 
http//www.bluepointenvironmental.com/wp-content/u
ploads/2012/01/coenocytic-hyphae-60x-LP.jpg
18
(No Transcript)
19
Significance

• decomposers
• food source of other organisms
• parasites of plants (grapes, tomatoes, potatoes)
  and animals
• used to plan routes (shortest distance)
• rich areas for biological study

http//www.gardencentre.ie/blog/wp-content/uploads
/2012/05/potato-blight.jpg, http//media.treehugge
r.com/assets/images/2011/10/tokyo-mold-railway.jpg