A Cyp51B Mutation Contributes to Azole Resistance in Aspergillus fumigatus

GONZÁLEZ JIMÉNEZ IRENE, Jose Lucio, Jorge Amich, Isabel Cuesta, Rafael Sanchez Arroyo, Laura Alcazar-Fuoli, Emilia Mellado

Research output: Contribution to journalArticlepeer-review

99 Downloads (Pure)


The emergence and spread of Aspergillus fumigatus azole resistance has been acknowledged worldwide. The main problem of azole resistance is the limited therapeutic options for patients suffering aspergillosis. Azole resistance mechanisms have been mostly linked to the enzyme Cyp51A, a target of azole drugs, with a wide variety of modifications responsible for the different resistance mechanisms described to date. However, there are increasing reports of A. fumigatus strains showing azole resistance without Cyp51A modifications, and thus, novel resistance mechanisms are being explored. Here, we characterized two isogenic A. fumigatus clinical strains isolated two years apart from the same patient. Both strains were resistant to clinical azoles but showed different azole resistance mechanisms. One strain (CM8940) harbored a previously described G54A mutation in Cyp51A while the other strain (CM9640) had a novel G457S mutation in Cyp51B, the other target of azoles. In addition, this second strain had a F390L mutation in Hmg1. CM9640 showed higher levels of gene expression of cyp51A, cyp51B and hmg1 than the CM8940 strain. The role of the novel mutation found in Cyp51B together with the contribution of a mutation in Hmg1 in azole resistance is discussed.
Original languageEnglish
JournalJournal of Fungi
Publication statusPublished - 26 Nov 2020


Dive into the research topics of 'A Cyp51B Mutation Contributes to Azole Resistance in Aspergillus fumigatus'. Together they form a unique fingerprint.

Cite this