Genomewide Elucidation of Drug Resistance Mechanisms for Systemically Used Antifungal Drugs Amphotericin B, Caspofungin, and Voriconazole in the Budding Yeast

Abstract

There are only a few antifungal drugs used systemically in treatment, and invasive fungal infections that are resistant to these drugs are an emerging problem in health care. In this study, we performed a high-copy-number genomic DNA (gDNA) library screening to find and characterize genes that reduce susceptibility to amphotericin B, caspofungin, and voriconazole in Saccharomyces cerevisiae. We identified the PDR16 and PMP3 genes for amphotericin B, the RMD9 and SWH1 genes for caspofungin, and the MRS3 and TRI1 genes for voriconazole. The deletion mutants for PDR16 and PMP3 were drug susceptible, but the other mutants had no apparent susceptibility. Quantitative-PCR analyses suggested that the corresponding drugs upregulated expression of the PDR16, PMP3, SWH1, and MRS3 genes. To further characterize these genes, we also profiled the global expression patterns of the cells after treatment with the antifungals and determined the genes and paths that were up- or downregulated. We also cloned Candida albicans homologs of the PDR16, PMP3, MRS3, and TRI1 genes and expressed them in S. cerevisiae. Heterologous expression of Candida homologs also provided reduced drug susceptibility to the budding yeast cells. Our analyses suggest the involvement of new genes in antifungal drug resistance.

Prevalence and Antifungal Susceptibility Pattern of Candida Isolates from Women with Recurrent Vulvovaginal Candidiasis in Ghana - A Review of Laboratory Reports.

“…Overexpression of multidrug resistance genes is responsible for the reduced susceptible proportions of Candida strains to voriconazole. These have been identi ed in uconazole and voriconazole-resistant strains of C. parapsilosis too (Balkan et al, 2019;Hu et al, 2019).…”

“…There are different resistance mechanisms but resistance to azole antifungal drugs is mostly due to modi cations in the target enzyme as a result of mutations (Balkan et al, 2019;Brilhante et al, 2019). Low access of azole drugs to the target site is also due to the over-expression of the ERG11 gene.…”

Assessment of the Antimicrobial, Antioxidant, and Antiproliferative Potential of Sideritis raeseri subps. raeseri Essential Oil

“…As the LPM model was not applicable to S. cerevisiae and A. niger due to yeast cell sedimentation and conidia flotation, the standard protocols described by The European Committee on Antimicrobial Susceptibility Testing (EUCAST) were applied for MIC determination [ 21 , 22 ], using voriconazole as positive control [ 23 , 24 ].…”

Antifungal drug resistance in Candida: a special emphasis on amphotericin B

“…The existence of altered sphingolipid profiles may also affect C. auris susceptibilities to AmB, according to a recent study on the sphingolipidomics of drug-resistant isolates of C. auris [204]. In addition, a genome-wide approach for studying drug resistance pathways, identified overexpression of phosphatidylinositol transfer protein (PDR16) confers resistance to AmB in S. cerevisiae and C. albicans [205,206]. The resistance provided by PDR16 overexpression may be connected to an alteration in membrane permeability and lipid composition as PDR16 affects the distribution of membrane ergosterols [207,208].…”

“…Sphingolipid molecules are critically important in several processes, including fungal virulence, pathogenicity, and cell growth. Sphingolipids also play a crucial role in AmB drug resistance, as indicated by the relevance of the PMP3 and PDR16 genes in classic genome-wide investigations of AmB drug resistance [205]. During infection, it is unknown how the AmB interacts with the pathogen or the host, because of the immunosuppressive properties of antifungal drugs.…”