The mitochondrial genome of Arthrinium arundinis and its phylogenetic position within Sordariomycetes.

Arthrinium arundinis is a common pathogen in nature, although its molecular taxonomic status has never been reported. Herein, we described the complete mitochondrial (mt) genome of A. arundinis, which is a circular DNA molecule with 48,975 bp in length; its A + T content is 72.04%. The mitogenome2, 23 tRNAs comprising 14 amino acids, 9 genes coding for proteins related to oxidative phosphorylation [nicotinamide adenine dinucleotide (nad) 1-5, nad4L, cytochrome b (cob), and cytochrome oxidase (cox) 1-2)], 3 ATP synthase subunits (atp6, atp8, and atp9), and 7 hypothetical proteins (orf73, orf143, orf252, orf266, orf328, orf341, and orf372). Phylogenetic analyses indicated that A. arundinis clustered with the members of the order Xylariales. Genome structure analyses showed that there are three blocks located in the mitogenome, including rns-rnl, nad2-nad5, and cob-atp6. The A. arundinis mitogenome presented features different from those of species in Xylariales, especially for the regions coding trns (trnR-trnY). In addition, comparison of the gene orders from species in Sordariomycetes revealed that although all coding regions are located on the same strand in most Sordariomycetes mitogenomes, several genes from A. arundinis presented reversed positions and co-localization of genes (i.e., nad1, nad4, and cox1).