Correlation between ERG11 Gene Mutations and Fluconazole Resistance in Candida albicans Strains Isolated from Rasht in Years 2015-2016

Abstract

Abstract Background: Candida albicans as an opportunistic fungal pathogen in human causes candidiasis. The widespread use of azoles has led to the increase of azole resistance in Candida albicans isolates. Mutation in the ERG11 gene is one of several azole resistance reasons in Candida albicans. The aim of this study was to find ERG11 gene mutations in fluconazole resistant isolates in Rasht. Materials and methods: Candida albicans isolates were identified by standard identification methods such as germ tubes. The fluconazole resistance and susceptibility of the isolates was evaluated by Disc diffusion and MIC methods. For mutation determining, ERG11 gene was amplified by PCR and then sequenced in clinical isolates. Results: From 23 isolates of Candida albicans, 20 isolates were fluconazole resistant. The MIC of fluconazole in these isolates was determined between 128 to 2048µg/ml. Also, sequencing analysis showed that 10 fluconazole resistant isolates had two missense mutations (D116E and E266D) in ERG11 gene. Conclusion: In this study, resistance to high concentration of fluconazole shows that different mechanisms simultaneously implicated in developing azoles resistance in the isolates. Association of ERG11 gene mutation and deregulation of other genes can be led to resistance to high fluconazole concentration in this study