Adherence of Candida albicans to silicone induces immediate enhanced tolerance to fluconazole.
Wild-type and efflux pump-deficient cells of Candida albicans adhering to silicone were compared with planktonic cells by flow cytometry for their relative resistance to fluconazole (FCZ). Flow cytometry data on cells carrying a fusion of green fluorescent protein to efflux pump promoters confirmed that enhanced tolerance of attached cells to FCZ was due in part to increased expression of CaMDR1 and CDR1 promoters. Within 2 h of their attachment to silicone, the adherent cells demonstrated levels of FCZ tolerance shown by cells from 24-h biofilms. Following their mechanical detachment, this subset of cells retained a four- to eightfold increase in tolerance compared with the tolerance of planktonic cells for at least two generations. Enhanced efflux pump tolerance to FCZ appeared to be induced within the initial 15 min of attachment in a subset of cells that were firmly attached to the substrata.
Georgia State University, Atlanta, Georgia, USA. carolina.maetus@milliken.com
Carolina
C
Mateus
Sidney A
SA
Crow
Donald G
DG
Ahearn
D018435:ATP Binding Cassette Transporter, Subfamily B / Q000096:biosynthesis / Q000235:genetics; D000935:Antifungal Agents / Q000494:pharmacology*; D018441:Biofilms; D002176:Candida albicans / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002448:Cell Adhesion; D015825:Chromosomes, Fungal / Q000235:genetics; D017931:DNA Primers; D025141:Drug Resistance, Fungal; D015725:Fluconazole / Q000494:pharmacology*; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D005838:Genotype; D008856:Microscopy, Fluorescence; D011401:Promoter Regions, Genetic / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012828:Silicones / Q000494:pharmacology*
D018435:ATP Binding Cassette Transporter, Subfamily B; D000935:Antifungal Agents; D017931:DNA Primers; D012828:Silicones; D015725:Fluconazole