Identificação de transcritos diferencialmente expressos por Cryptococcus gattii em condições de privação de ferro, caracterização molecular e perfil de susceptibilidade a antifúngicos de isolados clínicos veterinários

Abstract

Cryptococcus neoformans/gattii complex is a pathogen relevant to public health in Brazil and other countries. Molecular studies are important to understanding the epidemiology and biology of this yeast. Deprivation of some micronutrients, among them iron, can be related to expression of genes that contribute to the pathogenicity of the microorganism. The first part of this study aimed to analyze transcripts differentially expressed by C. gattii during iron deprivation using RDA approach (Representational Difference Analysis). Regarding the RDA, C. gattii expressed genes related to different biological processes such as ergosterol metabolism, cell cycle, lipid metabolism, transcriptional activators, organization of the wall and cell membrane. Thus, the second part of this study was to characterize the molecular type of 04 C. gattii clinical isolates from two cities of Mato Grosso State, determining mating-types, genetic diversity by PCR-fingerprinting and susceptibility to five antifungals by EtestTM. The four isolates in this study were identified as C. gattii VGII, MATα. The fungal strains were susceptible to ketoconazole, fluconazole, amphotericin B, voriconazole and susceptible dosedependent to itraconazole. Our results revealed novel genes involved in iron metabolism and will contribute to future eco-epidemiological studies in the country.