Molecular Evaluation of the mRNA Expression of the <i>ERG11</i>, <i>ERG3</i>, <i>CgCDR1</i>, and <i>CgSNQ2</i> Genes Linked to Fluconazole Resistance in <i>Candida glabrata</i> in a Colombian Population

Introduction: The study of <i>Candida glabrata</i> genes associated with fluconazole resistance, from a molecular perspective, increases the understanding of the phenomenon with a view to its clinical applicability. Objective: We sought to establish the predictive molecular profile of fluconazole resistance in <i>Candida glabrata</i> by analyzing the <i>ERG11</i>, <i>ERG3</i>, <i>CgCDR1</i>, and <i>CgSNQ2</i> genes. Method: Expression was quantified using RT-qPCR. Metrics were obtained through molecular docking and Fisher discriminant functions. Additionally, a predictive classification was made against the susceptibility of <i>C. glabrata</i> to fluconazole. Results: The relative expression of the <i>ERG3</i>, <i>CgCDR1</i>, and <i>CgSNQ2</i> genes was higher in the fluconazole-resistant strains than in the fluconazole-susceptible, dose-dependent strains. The gene with the highest relative expression in the fluconazole-exposed strains was <i>CgCDR1</i>, and in both the resistant and susceptible, dose-dependent strains exposed to fluconazole, this was also the case. The molecular docking model generated a median number of contacts between fluconazole and <i>ERG11</i> that was lower than the median number of contacts between fluconazole and <i>ERG3</i>, -<i>CgCDR1</i>, and -<i>CgSNQ2</i>. The predicted classification through the multivariate model for fluconazole susceptibility achieved an accuracy of 73.5%. Conclusion: The resistant strains had significant expression levels of genes encoding efflux pumps and the <i>ERG3</i> gene. Molecular analysis makes the identification of a low affinity between fluconazole and its pharmacological target possible, which may explain the lower intrinsic susceptibility of the fungus to fluconazole.