Systematics of methanol assimilating yeasts and neighboring taxa from multigene sequence analysis and the proposal of Peterozyma gen. nov., a new member of the Saccharomycetales

The relatedness among methanol-assimilating yeasts assigned to the genus Ogataea and neighboring taxa (Phylum Ascomycota, Subphylum Saccharomycotina, Class Saccharomycetes, Order Saccharomycetales) was determined from phylogenetic analyses of gene sequences for nuclear large and small subunit (SSU) rRNAs, translation elongation factor-1alpha and mitochondrial SSU rRNA. On the basis of the analyses, Williopsis salicorniae and seven species of Pichia are proposed for transfer to the genus Ogataea, which has been emended, and Pichia angophorae, a nonhyphal species, is proposed for transfer to the mycelium forming genus Ambrosiozyma. Pichia toletana and Pichia xylosa form an independent lineage and are assigned to the genus Peterozyma, which is newly proposed.