Candida albicans, like other pathogens, has to compete with the host for a limited supply of available iron. Consequently, iron acquisition is likely to be an important factor for the growth, survival and virulence of this organism. It was previously demonstrated that C. albicans has a surface-associated ferric reductase similar to that of Saccharomyces cerevisiae. Therefore, functional rescue of a S. cerevisiae fre1 mutant was used to isolate a C. albicans ferric reductase gene (CFL1). This gene has been previously identified. However, the workers had not observed any functional reductase activity associated with the gene. The discrepancy with the findings in this report appears to be due to the clone previously reported carrying a non-contiguous piece of C. albicans DNA. Results shown in this paper demonstrate that CFL1 transcription is regulated in response to levels of iron and copper. This is the first demonstration of a functional ferric reductase gene from C. albicans.
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Candida albicans CFL1 encodes a functional ferric reductase activity that can rescue a Saccharomyces cerevisiae fre1 mutantThe EMBL accession number for the sequence reported in this paper is AJ387722.