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Symbiotaphrina kochii (Pezizomycotina incertae sedis).

Symbiotaphrina is a genus of yeast-like endosymbionts of beetles that has been implicated in B-vitamin biosynthesis, fatty acid metabolism, and detoxification of noxious plant compounds by insects.  The fungi are transmitted vertically on the egg surface at deposition.  Neither the fungi nor beetles have been found in isolation.  The fungi have a number of positive effects on the insect hosts.  In particular they produce enzymes that degrade a wide variety of noxious compounds they use as carbon sources; these include flavonoids, tannic acid, phenol, plant meal toxins, certain mycotoxins and insecticides, and herbicides such as 2,4D, all compounds usually toxic to insects. The fungal symbionts allow some beetles known as cigarette beetles to even live in cigarette packs. The fungi also are involved with utilizing sterols and helping to recycle nitrogen within the fat bodies of the insect hosts. As such, there is a strong likelihood that these fungi are capable of unique metabolic activity of significant interest to DOE.

Symbiotaphrina has long been the subject of taxonomic confusion. There exists two known species, S. kochii and S. buchneri, and they were once considered to be members of the earliest diverging clade of Ascomycota, then members of the Saccharomycotina, and finally as Pezizomycotina . Although a member of the Pezizomycotina, current phylogenetic analyses support the genus as a unique and enigmatic lineage of the subphylum and potentially a new class.  Sequencing of the S. kochii genome will therefore inform phylogenetic analyses directed at unraveling its evolutionary origin and provide an important phylogenetic and ecological sampling point for understanding the complex evolutionary history of fungal metabolism.