Mechanisms of fluconazole resistance in clinical and experimental induced isolates of Candida glabrata / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the mechanisms of fluconazole resistance in clinical and experimental induced isolates of C.glabrata.Methods Efflux of rhodamine 6G was performed to evaluate the effects of efflux pumps.The expression levels of transporter genes CDR1,CDR2,SNQ2 and ERG11 were examined by real-time RT-PCR.Meanwhile,sequence of PDR1 was determined by PCR based DNA sequencing.Results Efflux pumps of all fluconazole-resistant isolates had stronger effects than that of susceptible isolates,consistently with significant upregulation of CDR1,but no obvious difference was found in CDR2 or SNQ2.Also,no notable change in the expression level of ERG11 between susceptible and resistant isolates.PDR1 mutations existed in both clinical and experimental induced isolates of C.glabrata,among which P927S,L543P and S947L haven't been reported previously.Conclusion Mutations of PDR1 were induced by fluconazole both in vivo andin vitro,which will result in overexpression of CDR1 and strengthen the effect of efflux pump.