Candida albicans gene encoding resistance to benomyl and methotrexate is a multidrug resistance gene

Candida albicans is not inhibited by a number of drugs known to affect fungal cells. The basis for this resistance in most cases is unknown but has been attributed to the general impermeability of the fungal cell envelope. A gene (BEN(r)) formerly shown to be responsible for the resistance of C. albicans to benomyl and methotrexate was shown in the present study to confer resistance to four other inhibitory compounds: cycloheximide, benztriazoles, 4-nitroquinoline-N-oxide, and sulfometuron methyl. Analysis of the protein database revealed an apparent similarity of the C. albicans gene to membrane protein genes encoding antibiotic resistance in prokaryotes and eukaryotes and a high degree of identity to a recently cloned gene encoding cycloheximide resistance in Candida maltosa. We propose that BEN(r) encodes a protein that operates in a fashion similar, but not identical, to that described for other multiple-drug resistance proteins.