THE CANDIDA-ALBICANS PMM1 GENE ENCODING PHOSPHOMANNOMUTASE COMPLEMENTS A SACCHAROMYCES-CEREVISIAE-SEC 53-6 MUTATION

We have constructed an ordered-array genomic DNA library of the pathogenic dimorphic fungus Candida albicans which facilitates the rapid cloning of C. albicans genes by hybridisation. Using the Saccharomyces cerevisiae SEC53 gene encoding phosphomannomutase as a hybridisation probe we have cloned the C. albicans homologue, PMM1, and determined its sequence. This gene shows high similarity, both at the nucleotide (76.2%) and amino-acid (77.7%) level, to the S. cerevisiae SEC53 gene. We have used the C. albicans PMM1 gene, in single copy, to transform temperature-sensitive S. cerevisiae sec53-6 mutant cells, which are defective in PMM activity at 37-degrees-C, to growth at 37-degrees-C. The C albicans PMM1 gene is thus the structural and functional equivalent of the SEC53 gene.