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Updated: Jul 16, 2026
08:45
Whole Genome Sequencing of Candida glabrata for Detection of Markers of Antifungal Drug Resistance
Published on: December 28, 2017
A purine permease in Candida glabrata
S Sen Gupta1, D Kerridge, M R Chevallier
1Yale Universtiy School of Medicine, Department of Genetics, New Haven, Connecticut 06510-8005.
FEMS Microbiology Letters
|February 1, 1995
Summary
Candida glabrata 4 possesses a distinct purine permease for adenine and guanine transport, separate from its cytosine permease. This finding differs from related yeast species, highlighting unique nutrient transport mechanisms.
Area of Science:
- Microbiology
- Yeast Genetics
- Molecular Transport
Background:
- Candida glabrata is an important human pathogen.
- Nutrient transport systems are crucial for microbial growth and survival.
- Previous studies in Saccharomyces cerevisiae and Candida albicans identified broad-specificity permeases for purines and pyrimidines.
Purpose of the Study:
- To investigate the purine and pyrimidine transport mechanisms in Candida glabrata.
- To characterize the substrate specificity of permeases in C. glabrata.
- To compare the transport systems of C. glabrata with those of other yeast species.
Main Methods:
- Isolation of a cytosine permease-negative mutant of C. glabrata using 5-fluorocytosine selection.
- Competition experiments to assess the transport of various nucleobases (adenine, guanine, cytosine, hypoxanthine) in wild-type and mutant strains.
- Analysis of substrate uptake in the presence of competing nucleobases.
Main Results:
- A specific purine permease transports adenine and guanine in Candida glabrata.
- The isolated mutant was confirmed to be negative for cytosine permease activity.
- No transport system for hypoxanthine was detected in C. glabrata.
- The purine permease in C. glabrata exhibits different substrate specificity compared to S. cerevisiae and C. albicans.
Conclusions:
- Candida glabrata possesses at least two distinct permease systems: one for cytosine and another for purines (adenine and guanine).
- This purine permease is distinct from the broader specificity permeases found in Saccharomyces cerevisiae and Candida albicans.
- The findings reveal unique nucleobase transport mechanisms in C. glabrata, relevant for understanding its metabolism and potential as a pathogen.
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