Studyof resistance of pathogenic and opportunistic fungi toantimycotics

The widespread use of antimycotic agents for the treatment of mycoses in humans and animals is of concern to medical and veterinary specialists due to the emergence of resistance of pathogenic and opportunistic fungi to antifungal agents. In recent years, information has been accumulated on the various molecular mechanisms underlying this phenomenon, but in-depth studies are needed to successfully predict resistance in various groups of fungi. To treat and prevent fungal infections several groups of antimycotics are used, where azoles and allylamines are the most frequent ones, which leads to resistance development in pathogenic and opportunistic fungi. The article presents the results of molecular methods identification of azole-resistant Candida albicans isolates and terbinafine-resistant Trichophyton isolates. The analysis of gene ERG11 nucleotide sequences of 10 Candida albicans isolates, recovered from different animal species, enabled the division of phenotypically resistant and susceptible strains, but could not differentiate between the strains, which have dose-dependent resistance to azoles. Study of single nucleotide polymorphisms in gene SQLE, associated with the resistance development to terbinafine in 12 fungal isolates of genus Trichophyton, did not allow grading them by their resistance, which is likely associated with another resistance mechanism, which can be observed in these strains. The results obtained can serve as a basis for the use of molecular methods to characterize fungi of Candida and Trichophyton genera, however, taking into account the biological features of pathogens from different groups it is reasonable to use several significant genome regions or the results of the whole genome sequencing, as well as the gene expression analysis for successful forecasting of potential resistance. 

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