cerevisiae

Saccharomyces cerevisiae, commonly known as baker's yeast or brewer's yeast, is a species of single-celled fungus in the phylum Ascomycota. It is a widely used organism in food production and scientific research. In its natural environment it occurs on the skins of fruits and in other sugary niches, but it is most notable for its role in fermentation.

In the laboratory, S. cerevisiae reproduces primarily by budding. It is a facultative anaerobe and can metabolize glucose by respiration or fermentation. The genome is about 12 million base pairs and contains roughly 6,000 genes. It is a leading model organism for eukaryotic genetics and cell biology; a reference strain (S288C) and comprehensive gene-deletion collections have facilitated functional studies. The genome sequence was published in 1996, marking it as one of the first eukaryotic genomes.

Industrial and medical uses include baking bread, brewing beer and wine, and production of bioethanol and recombinant proteins. S. cerevisiae strains are also used in biotechnology and research, and a probiotic variant, Saccharomyces boulardii, is marketed for gut health. Safety regulations generally recognize domesticated S. cerevisiae strains as safe for food and industrial applications.