title: 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.
authors.affiliation: Mycology Unit, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Rasmus Hare
authors.identifier: 0000-0002-9796-023X
authors.initials: RH
authors.lastname: Jensen
authors.forename: Helle Krogh
authors.initials: HK
authors.lastname: Johansen
authors.forename: Maiken Cavling
authors.initials: MC
authors.lastname: Arendrup
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics*; D000935:Antifungal Agents / Q000494:pharmacology / Q000627:therapeutic use; D041022:Candida tropicalis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D002177:Candidiasis / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology; D002999:Clone Cells; D025141:Drug Resistance, Fungal / Q000235:genetics; D054714:Echinocandins / Q000494:pharmacology / Q000627:therapeutic use; D005656:Fungal Proteins / Q000235:genetics*; D005964:Glucosyltransferases / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D009154:Mutation; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology; D011392:Proline / Q000235:genetics; D017422:Sequence Analysis, DNA; D012694:Serine / Q000235:genetics
chemical_list: D000935:Antifungal Agents; D054714:Echinocandins; D005656:Fungal Proteins; D012694:Serine; D011392:Proline; D005964:Glucosyltransferases