Abstract：The aim of this study is to investigate the resistant rate of Candida albicans (C. albicans) isolates against fluconazole, and to determine the correlation between the fluconazole-resistance and CAP1 gene of C. albicans. The microdilution test on 245 C. albicans isolates showed that 134 strains were fluconazole-sensitive (MIC≤8 μg/mL), 36 strains were fluconazole-dose-dependent sensitive (16-32 μg/mL) and 75 strains were fluconazole-resistant (≥64 μg/mL) that produced a 30.6% (75/245) fluconazole-resistant rate. The real-time fluorescent quantitative RT-PCR (qRT-PCR) and flow cytometric examination confirmed that the mRNA (CAP1-mRNA) and Cap1p levels expressed by CAP1 gene in the fluconazole-resistant C. albicans isolates were significantly higher than those in the fluconazole-sensitive isolates (P<0.05). When the fluconazole-sensitive C. albicans isolates were continuously cultured in YPD liquid medium containing fluconazole with progressively-increased dosages (4-64 μg/mL), the isolates produced the resistance against fluconazole (MIC≥64 μg/mL) as well as the CAP1-mRNA and Cap1p expression levels were significantly elevated (P<0.05). All the data indicate that C. albicans isolates have a higher fluconazole-resistant rate. Fluconazole can induce the resistance against itself in fluconazole-sensitive C. albicans strains. The fluconazole-resistance of C. albicans is closely associated with the expression up-regulation of its CAP1 gene.
谈潘莉, 汪浙炯, 赵金方. 白假丝酵母菌临床菌株对氟康唑耐药性及其与CAP1基因相关性研究[J]. 中国人兽共患病学报, 2015, 31(4): 325-329.
TAN Pan-li, WANG Zhe-jiong, ZHAO Jin-fang. Resistance of Candida albicans isolates against fluconazole and the resistance correlation with CAP1 gene. Chinese Journal of Zoonoses, 2015, 31(4): 325-329.
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