Fungal propagules and DNA in feces of two detritus-feeding amphipods.
Aquatic shredders (leaf-eating invertebrates) preferentially ingest and digest leaves colonized by aquatic hyphomycetes (fungi). This activity destroys leaf-associated fungal biomass and detritial resources in streams. Fungal counter-adaptations may include the ability to survive passage through the invertebrate's digestive tract. When fecal pellets of Gammarus tigrinus and Hyalella azteca were incubated with sterile leaves, spores of nine (G. tigrinus) and seven (H. azteca) aquatic hyphomycete species were subsequently released from the leaves, indicating the presence of viable fungal structures in the feces. Extraction, amplification, and sequencing of DNA from feces revealed numerous fungal phylotypes, two of which could be assigned unequivocally to an aquatic hyphomycete. The estimated contributions of major fungal groups varied depending on whether 18S or ITS sequences were amplified and cloned. We conclude that a variable proportion of fungal DNA in the feces of detritivores may originate from aquatic hyphomycetes. Amplified DNA may be associated with metabolically active, dormant, or dead fungal cells.
Sridhar
Kandikere Ramaiah
KR
Department of Biosciences, Mangalore University, Mangalagangotri, Mangalore, 574 199, Karnataka, India.
Beaton
Margaret
M
Bärlocher
Felix
F
D033304:Amphipoda / Q000382:microbiology*; D000818:Animals; D044822:Biodiversity; D004271:DNA, Fungal / Q000235:genetics*; D005243:Feces / Q000737:chemistry / Q000382:microbiology*; D020387:Food Chain; D003904:Mitosporic Fungi / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D018515:Plant Leaves / Q000382:microbiology; D013172:Spores, Fungal / Q000235:genetics; D014871:Water Microbiology
D004271:DNA, Fungal