Torulopsis

Torulopsis is a historically used genus of yeasts in the phylum Ascomycota, within the order Saccharomycetales. The genus was used to group several unicellular ascomycetous yeasts that reproduce primarily by budding. With the rise of molecular phylogenetics, many species once placed in Torulopsis were reassigned to other genera, especially Candida, Kluyveromyces, and Tetrapisispora. As a result, Torulopsis is now regarded largely as an obsolete or deprecated genus name, retained mainly in older literature.

Morphology and physiology: As with other Saccharomycetales, Torulopsis species are unicellular yeasts, typically oval to spherical, reproducing asexually by budding. They form creamy to smooth colonies on standard yeast media and can ferment sugars to alcohol and carbon dioxide under appropriate conditions.

Ecology and significance: Historically, yeasts attributed to Torulopsis have been isolated from diverse environments, including dairy products and other fermentation settings. Some species have served in research on sugar metabolism, enzyme production, and fermentation processes. In medicine, at least one species formerly placed in Torulopsis is now recognized in the Candida lineage and can act as an opportunistic pathogen in humans.

Notable species: A well-known example is Torulopsis glabrata, now Candida glabrata, an opportunistic pathogen associated with human infections.