Schizosaccharomyces pombe

Schizosaccharomyces pombe, commonly known as fission yeast, is a single-celled eukaryote used both in traditional beer-making and as a laboratory model for studying molecular and cell biology. Its cells are rod-shaped, typically 3 to 4 micrometers wide and 7 to 14 micrometers long. The genome spans about 14.1 million base pairs and is thought to hold around 4,970 protein-coding genes and at least 450 non-coding RNAs. These cells grow only at their tips and reproduce by splitting down the middle, producing two equally sized daughter cells—a trait that makes them especially useful for research on the cell cycle. The species was first isolated in 1893 by Paul Lindner from an East African millet beer. Its name comes from the Swahili word for beer, *pombe*. It was turned into an experimental model in the 1950s: Urs Leupold used it for genetics, and Murdoch Mitchison for cell cycle studies. Later, researcher Paul Nurse brought together these two lines of work, and along with Lee Hartwell and Tim Hunt, won the 2001 Nobel Prize in Physiology or Medicine for discoveries about cell cycle control. In 2002, a consortium led by the Sanger Institute published the full genome sequence of *S. pombe*, making it the sixth model eukaryote to be fully sequenced. Researchers are supported by the PomBase model organism database, which has helped reveal that about 70% of *S. pombe* genes have counterparts in humans, including many linked to human disease. In 2006, the locations of nearly all its proteins within the cell were mapped using green fluorescent protein tags. The yeast is also widely used to study how cells respond to DNA damage and how DNA replication works. Around 160 natural strains of *S. pombe* have been collected from Europe, the Americas, and Asia. Most come from cultivated fruits like apples and grapes, or from alcoholic drinks such as Brazilian Cachaça. It has also been found in fermented tea, kombucha, though it is unclear whether it plays a major role in fermentation there or is just a contaminant. The natural ecology of *Schizosaccharomyces* yeasts remains poorly understood. The species was first discovered in 1893 by a group at a Brewery Association Laboratory in Germany, who examined sediment from an acidic millet beer imported from East Africa. The prefix *schizo* means "split" or "fission" and had been used for other *Schizosaccharomycetes*.