Genome sequence of <i>Pseudopithomyces chartarum</i>, causal agent of facial eczema (pithomycotoxicosis) in ruminants, and identification of the putative sporidesmin toxin gene cluster

Facial eczema (FE) in grazing ruminants is a debilitating liver syndrome induced by ingestion of sporidesmin, a toxin belonging to the epipolythiodioxopiperazine class of compounds. Sporidesmin is produced in spores of the fungus <i>Pseudopithomyces chartarum</i>, a microbe which colonises leaf litter in pastures. New Zealand has a high occurrence of FE in comparison to other countries as animals are fed predominantly on ryegrass, a species that supports high levels of <i>Pse. chartarum</i> spores. The climate is also particularly conducive for <i>Pse. chartarum</i> growth. Here, we present the genome of <i>Pse. chartarum</i> and identify the putative sporidesmin gene cluster. The <i>Pse. chartarum</i> genome was sequenced using single molecule real-time sequencing (PacBio) and gene models identified. Loci containing genes with homology to the aspirochlorine, sirodesmin PL and gliotoxin cluster genes of <i>Aspergillus oryzae</i>, <i>Leptosphaeria maculans</i> and <i>Aspergillus fumigatus</i>, respectively, were identified by tBLASTn. We identified and annotated an epipolythiodioxopiperazine cluster at a single locus with all the functionality required to synthesise sporidesmin.