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Stepwise development of a homozygous S80P substitution in Fks1p, conferring echinocandin resistance in Candida tropicalis.

ABSTRACT: Three Candida tropicalis isolates were obtained from a patient with acute lymphoblastic leukemia. The first isolate was susceptible to all drug classes, while isolates 2 and 3, obtained after 8 and 8.5 weeks of caspofungin treatment, respectively, were resistant to the three echinocandins. Multilocus sequence genotyping suggested a clonal relation among all isolates. FKS1 sequencing revealed a stepwise development of a heterozygous and finally a homozygous mutation, leading to S80S/P and S80P amino acid substitutions.

SUBMITTER: Jensen RH

PROVIDER: S-EPMC3535961 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Stepwise development of a homozygous S80P substitution in Fks1p, conferring echinocandin resistance in Candida tropicalis.

Jensen Rasmus Hare RH Johansen Helle Krogh HK Arendrup Maiken Cavling MC

Antimicrobial agents and chemotherapy 20121022 1

Three Candida tropicalis isolates were obtained from a patient with acute lymphoblastic leukemia. The first isolate was susceptible to all drug classes, while isolates 2 and 3, obtained after 8 and 8.5 weeks of caspofungin treatment, respectively, were resistant to the three echinocandins. Multilocus sequence genotyping suggested a clonal relation among all isolates. FKS1 sequencing revealed a stepwise development of a heterozygous and finally a homozygous mutation, leading to S80S/P and S80P am ...[more]

PMID: 23089761

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