Utility of a proposed CSP typing nomenclature for Australian Aspergillus fumigatus isolates: Identification of additional CSP types and suggested modifications

Abstract

A recently developed CSP typing scheme and proposed nomenclature was applied to a collection of 164 clinical and environmental Aspergillus fumigatus isolates from Melbourne, Australia. Fifteen CSP variants were observed overall, including three that were not reported in the original nomenclature that described 19 CSP variants, raising the possibility of phylogeographic differences between the Australian and the previously studied European and North American A. fumigatus populations. However, those CSP variants that were common between this and the previous studies appeared to have a broadly similar prevalence. The presence of an additional CCT codon in the 3′ flanking region of some CSP variants was also observed in homologous Neosartorya fischeri sequence, suggesting that the absence of this codon in other isolates is due to codon deletion, rather than its presence representing a duplication. We recommend a number of modifications to the proposed CSP type nomenclature to accommodate these new findings.