Saccharomyces cerevisiae is a species of
yeast. It has been instrumental to
winemaking,
baking, and
brewing since ancient times. It is believed to have been originally isolated from the skin of grapes (one can see the yeast as a component of the thin white film on the skins of some dark-colored fruits such as plums; it exists among the waxes of the
cuticle). It is one of the most intensively studied
eukaryotic model organisms in
molecular and
cell biology, much like
Escherichia coli as the model
bacterium. It is the microorganism behind the most common type of
fermentation.
S. cerevisiae cells are round to ovoid, 5–10
µm in diameter. It reproduces by a division process known as
budding.