Aspergillus section Fumigati の系統分類と最近の動向

抄録

Aspergillus fumigatus is distributed worldwide in soil, air, foods, feeds, compost, and human habitats. Aspergillus fumigatus and its related species, including the genus Neosartorya, which is a teleomorph of Aspergillus, are the most important causative agents of aspergillosis. These species belong to Aspergillus section Fumigati. Conidiogenesis and conidial ornamentation are important morphological characters for distinguishing Aspergillus species. The teleomorph of Aspergillus has various ascospore ornamentations, and these are characteristic of species discrimination.

Rules for the systematic biology of Aspergillus were suggested in 2007, and since then the partial β-tubulin, calmodulin, actin, and RNA polymerase genes and the internal transcribed spacer (ITS) region have been used for the taxonomy of Aspergillus. The β-tubulin and calmodulin genes, in particular, have been well analyzed in Aspergillus and its related genera.

The correlations among molecular phylogenetics and phenotypic characters have been investigated well in Aspergillus. Molecular phylogenetics has become a useful tool for distinguishing species of Aspergillus and its related genera, and many new species have been discovered and described since 2007.

In section Fumigati, several species (especially A. udagawae and A. viridinutans) show within-species diversity of DNA sequences. Recently, several researchers have reevaluated A. viridinutans by using a mating test. As a result, A. viridinutans has been separated into seven species on the basis of conidial or ascospore morphology. Application of systematic biology has promoted variation in the modern taxonomy of Aspergillus.