Anaerobic fungi and herbivores

Anaerobic fungi Neocallimastigomycotina participate in rumen symbiotic microbiome. This highly specific group of fungi are a part of the basal lineages of the Fungi kingdom, differing from their aerobic counterparts in many aspects, including the possession of hydrogenosomes and the production of cellulosomes. Their entire life cycle occurs in the rumen, comprising of motile zoospores, which after colonizing plant biomass, germinate into vegetative thallus, forming a sporangium. In the rumen ecosystem, anaerobic fungi are primary colonizers of ingested plant biomass, where with the help of extracelullar multienzyme complexes- cellulosomes- degrade recalcitrant plant cell wall. The ability to form cellulosomes, until now observed in prokaryots only, was acquired by horizontal gene transfer from rumen symbiotic bacteria. Their long coevolution also led to many syntrophic interactions with methanogens, which utilise H2 produced by fungal hydrogenosomes. Their potential use in biotechnology includes biogas production and increased digestibility of agricultural feed. Key words: anaerobic fungi, rumen, hydrogenosome, cellulosom