Two independent studies reveal that Candida albicans, the fungus responsible for oral thrush and vaginal yeast infections, can recombine sexually. Although other members of the budding-yeast family have sexual cycles, C. albicans has been classified for 80 years as asexual.
In two papers in the July 14 Science, researchers at the University of California, San Francisco and the University of Minnesota in St. Paul report that C. albicans can mate, but only under limited circumstances.
C. albicans possesses genes that control mating in related species, but scientists had thought that these genes are inactive in this fungus. The Minnesota researchers, Beatrice B. Magee and Paul T. Magee, altered the growth conditions of the yeast to produce strains lacking one version or the other of a mating gene, MTL. Placed on lab plates, the yeast mated across, but not within, the strains.