Novel Non-Hot Spot Modification in Fks1 of Candida auris Confers Echinocandin Resistance.

We determined the echinocandin susceptibility and FKS1 genotypes of 13 clinical isolates of Candida auris that were recovered from 4 patients at a tertiary care center in Salvador, Brazil. Three isolates were categorized as echinocandin-resistant, and they harbored a novel FKS1 mutation that led to an amino acid change W691L located downstream from hot spot 1. When introduced to echinocandin-susceptible C. auris strains by CRISPR/Cas9, Fks1 W691L induced elevated MIC values to all echinocandins (anidulafungin, 16 to 32×; caspofungin, >64×; micafungin, >64×).