Mutation of the CgPDR16 gene attenuates azole tolerance and biofilm production in pathogenic Candida glabrata.
The PDR16 gene encodes the homologue of Sec14p, participating in protein secretion, regulation of lipid synthesis and turnover in vivo and acting as a phosphatidylinositol transfer protein in vitro. This gene is also involved in the regulation of multidrug resistance in Saccharomyces cerevisiae and pathogenic yeasts. Here we report the results of functional analysis of the CgPDR16 gene, whose mutation has been previously shown to enhance fluconazole sensitivity in Candida glabrata mutant cells. We have cloned the CgPDR16 gene, which was able to complement the pdr16Δ mutation in both C. glabrata and S. cerevisiae. Along with fluconazole, the pdr16Δ mutation resulted in increased susceptibility of mutant cells to several azole antifungals without changes in sensitivity to polyene antibiotics, cycloheximide, NQO, 5-fluorocytosine and oxidants inducing the intracellular formation of reactive oxygen species. The susceptibility of the pdr16Δ mutant strain to itraconazole and 5-fluorocytosine was enhanced by CTBT [7-chlorotetrazolo(5,1-c)benzo(1,2,4)triazine] inducing oxidative stress. The pdr16Δ mutation increased the accumulation of rhodamine 6G in mutant cells, decreased the level of itraconazole resistance caused by gain-of-function mutations in the CgPDR1 gene, and reduced cell surface hydrophobicity and biofilm production. These results point to the pleiotropic phenotype of the pdr16Δ mutant and support the role of the CgPDR16 gene in the control of drug susceptibility and virulence in the pathogenic C. glabrata.
Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, 842 15, Bratislava, Slovak Republic.
Hana
H
Culakova
Vladimira
V
Dzugasova
Jana
J
Perzelova
Yvetta
Y
Gbelska
Julius
J
Subik
D000935:Antifungal Agents / Q000494:pharmacology*; D001393:Azoles / Q000494:pharmacology*; D018441:Biofilms / Q000254:growth & development*; D041221:Candida glabrata / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000235:genetics; D026141:Drug Resistance, Multiple, Fungal / Q000235:genetics*; D015725:Fluconazole / Q000494:pharmacology; D015966:Gene Expression Regulation, Fungal; D057927:Hydrophobic and Hydrophilic Interactions; D017964:Itraconazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D009154:Mutation; D018384:Oxidative Stress / Q000187:drug effects; D049294:Phospholipid Transfer Proteins / Q000235:genetics / Q000378:metabolism*; D011090:Polyenes / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012235:Rhodamines / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D014227:Triazines / Q000494:pharmacology; D037521:Virulence Factors
C518245:7-chlorotetrazolo(5,1-c)benzo(1,2,4)triazine; D000935:Antifungal Agents; D001393:Azoles; D004271:DNA, Fungal; D049294:Phospholipid Transfer Proteins; D011090:Polyenes; D017382:Reactive Oxygen Species; D012235:Rhodamines; D014227:Triazines; D037521:Virulence Factors; C026188:rhodamine 6G; D017964:Itraconazole; D015725:Fluconazole
Candida glabrata; PDR16; biofilm; multidrug resistance; rhodamine 6G; virulence