2.1 Fungal materials and DNA extraction
O. xuefengensis strain HCMA001 was used in this study for mitogenomic analysis. In vitromycelial fermentation in liquid culture was conducted in Erlenmeyer flasks with shaking at 150 rpm in an incubator at 25°C for 10 days. Mycelia were collected by centrifugation and quickly frozen in liquid nitrogen. Total genomic DNA was then extracted using an improved extraction method [40]. Genomic DNA was quantified using an TBS-380 fluorometer (Turner BioSystems Inc., Sunnyvale, CA). High quality DNA samples (OD260/280=1.8~2.0, > 6 ug) were used to construct fragment libraries for genomic sequencing.