Project name: Aspergillus fumigatus

Description: Azole-resistant Aspergillus fumigatus isolates recovered at high frequency from patients, harbour mutations that are associated with variation of promoter length in the cyp51A gene. Following the discovery of the TR34/L98H genotype, new variations in tandem repeat (TR) length and number of repeats were identified, as well as additional single nucleotide polymorphisms (SNPs) in the cyp51A gene, indicating that the diversity of resistance mutations in A. fumigatus is likely to continue to increase. Investigating the development routes of TR variants is critical to be able to design preventive interventions. In this study, we tested the potential effects of azole exposure on the selection of TR variations, while allowing haploid A. fumigatus to undergo asexual reproduction. Through experimental evolution involving voriconazole (VOR) exposure, an isolate harbouring TR343/L98H evolved from a clinical TR34/L98H ancestor isolate, confirmed by whole genome sequencing. TR343/L98H was associated with further increase of VOR and posaconazole MICs and increased cyp51A expression. Exposure to medical azoles was found to select for TR343, thus supporting the possibility of in-host selection of TR34 variants.

Data type: genome sequencing

Sample scope: Monoisolate

Last updated: 2020-10-01