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07:32
Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans
Published on: March 19, 2015
Dynamic and heterogeneous mutations to fluconazole resistance in Cryptococcus neoformans
1Department of Microbiology, Duke University Medical Center, Durham, North Carolina 27710, USA. jpxu@mcmaster.ca
Antimicrobial Agents and Chemotherapy
|February 13, 2001
Summary
Cryptococcus neoformans develops fluconazole resistance through varied mutation rates. This study found no direct link between a strain's initial resistance and its mutation speed, highlighting dynamic resistance development.
Area of Science:
- Mycology
- Antimicrobial Resistance
- Medical Mycology
Background:
- Cryptococcus neoformans is a human pathogen causing serious infections.
- Fluconazole is a primary antifungal treatment for C. neoformans.
- Emerging fluconazole resistance necessitates understanding resistance mechanisms.
Purpose of the Study:
- To investigate in vitro mutation patterns leading to fluconazole resistance in Cryptococcus neoformans.
- To determine the mutation rates of fluconazole resistance in various C. neoformans strains.
- To explore potential correlations between baseline fluconazole MIC and mutation rates.
Main Methods:
- Determined Minimum Inhibitory Concentrations (MICs) of fluconazole for 21 C. neoformans strains.
- Cultured six independent cultures per strain on fluconazole-containing agar to assess mutation rates.
- Subcultured and re-tested MICs for putative fluconazole-resistant mutants.
Main Results:
- Significant heterogeneity in mutation rates for fluconazole resistance was observed across the 21 strains.
- Mutant MICs varied widely, from original strain MICs up to 64 microg/ml.
- No significant correlation was found between a strain's original fluconazole MIC and its mutation rate.
Conclusions:
- Fluconazole resistance in C. neoformans arises from dynamic and heterogeneous mutational processes.
- The development of resistance is complex and not solely dependent on initial susceptibility levels.
- Further research into the genetic underpinnings of C. neoformans fluconazole resistance is warranted.
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