Saccharomyces uvarum
Species of fungus
From Wikipedia, the free encyclopedia
Saccharomyces uvarum is a species of yeast that is commonly found in fermented beverages, particularly those fermented at colder temperatures.[1] It is found in cider (fruit), wine (grape), and beer (cereal)-brewing locations as well as on oak tree barks in nature.[2] It was originally described by Martinus Willem Beijerinck in 1898, but was long considered identical to S. bayanus.[1][3] In 2000 and 2005, genetic investigations of various Saccharomyces species indicated that S. uvarum is genetically distinct from S. bayanus and should be considered a unique species.[1][3]
| Saccharomyces uvarum | |
|---|---|
| Scientific classification | |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Saccharomycetes |
| Order: | Saccharomycetales |
| Family: | Saccharomycetaceae |
| Genus: | Saccharomyces |
| Species: | S. uvarum |
| Binomial name | |
| Saccharomyces uvarum Nguyen & Gaillardin ex. Beijerinck | |
| Type strain | |
| CBS 395 | |
| Synonyms | |
|
Saccaromyces bayanus var. uvarum | |

It is a bottom-fermenting yeast, so-called because it does not form the foam on top of the wort that top-fermenting yeast does.
Several genomes are available for S. uvarum, a recent one being a long read sequence of the strain CBS 7001, a more fertile relative of the type strain CBS 395. Each haploid genome includes 16 chromosomes.[4] Unlike natural strains, human-associated strains show introgression from S. eubayanus and S. kudriavzevii.[2] There has been multiple independent hybridization events with S. eubayanus and subsequent backcrossing in collected strains. Yeasts with high S. eubayanus and S. uvarum are considered undesired producers of off-flavors in beer-brewing partly due to 4-vinyl guaiacol production.[5]