Novel non hot spot modification in Fks1 of Candida auris confers echinocandin resistance

Kordalewska, M.; Cancino-Prado, G.; Nobrega de Almeida, J.; Brasil Brandao, I.; Tigulini de Souza Peral, R.; Lopes Colombo, A.; Perlin, D. S.

doi:10.1101/2023.03.29.534846

bioRxiv · 10.1101/2023.03.29.534846

Novel non hot spot modification in Fks1 of Candida auris confers echinocandin resistance

Kordalewska, M.·Cancino-Prado, G.·Nobrega de Almeida, J.·Brasil Brandao, I.·Tigulini de Souza Peral, R.·Lopes Colombo, A.·Perlin, D. S.

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Abstract

We determined echinocandin susceptibility and FKS1 genotypes of thirteen clinical isolates of Candida auris recovered from four patients at a tertiary care center in Salvador, Brazil. Three isolates were categorized as echinocandin-resistant and harbored a novel FKS1 mutation leading 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 (ANF 16-32x; CAS >64x; MCF >64x).

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Kordalewska, M., Cancino-Prado, G., Nobrega de Almeida, J., Brasil Brandao, I., Tigulini de Souza Peral, R., Lopes Colombo, A., Perlin, D. S.. 2023-04-03. Novel non hot spot modification in Fks1 of Candida auris confers echinocandin resistance. https://doi.org/10.1101/2023.03.29.534846

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