Phylogeny of the industrial relevant, thermophilic genera Myceliophthora and Corynascus

Species of the genus Myceliophthora and its teleomorph Corynascus have attracted increasing interest due to their potential to produce thermostable enzymes. This study re-assessed the phylogenetic relationship of 49 isolates of nine species belonging to Myceliophthora and Corynascus. One species, M. vellerea, was shown not to belong to the genus Myceliophthora and should be placed in the genus Ctenomyces. The other species belonged to two phylogenetic clusters: mesophilic fungi with the type species M. lutea and C. sepedonium, and thermophilic fungi with M. thermophila, M. hinnulea and C. thermophilus. The phylogenetic data provides no clear separation of the two genera Corynascus and Myceliophthora. To avoid confusion in future taxonomic studies, it is proposed that all existing Corynascus species be renamed to Myceliophthora, which is the old name and the one more frequently used. Furthermore, this study identified two groups within the isolates listed as M. thermophila and assigned one group (five isolates) to M. heterothallica based on AFLP analysis and mating behavior. This study provides new insights into the genetic differences within the genus Myceliophthora and will therefore be essential for the interpretation of future genomic and physiological studies of these species.