Candida krusei
| Candida krusei | |
|---|---|
| Scientific classification | |
| Kingdom: | Fungi |
| Phylum: | Ascomycota |
| Subphylum: | Saccharomycotina |
| Class: | Saccharomycetes |
| Order: | Saccharomycetales |
| Family: | Saccharomycetaceae |
| Genus: | Candida |
| Species: | C. krusei |
| Binomial name | |
| Candida krusei (Castellani) Berkhout | |
Candida krusei is a budding yeast (a species of fungus) involved in chocolate production. Candida krusei is an emerging fungal nosocomial pathogen primarily found in the immunocompromised and those with hematological malignancies. It has natural resistance to fluconazole, a standard antifungal agent. It is most often found in patients who have had prior fluconazole exposure, sparking debate and conflicting evidence as to whether fluconazole should be used prophylactically. Mortality due to C. krusei fungemia is much higher than the more common C. albicans. Other Candida species that also fit this profile are C. parapsilosis, C. glabrata, C. tropicalis, C. guillermondii and C. rugosa.
Candida krusei can be successfully treated with voriconazole, amphotericin B, and the echinocandins micafungin, caspofungin, and anidulafungin.
Role in chocolate production
Cacao beans have to be fermented to remove the bitter taste and break them down. This takes place with two fungi, C. krusei, and Geotrichum. Most of the time, the two fungi are already present on the seed pods and seeds of the cacao plant, but in modern chocolate making, specific strains are used. Each chocolate company uses its own strains, which have been selected to provide optimum flavor and aroma to the chocolate. The yeasts reproduce every few hours, and soon there are thousands of individual yeast cells in a small area, which produce enzymes to break down the pulp on the outside of the beans. This makes acetic acid, killing the cacao embryo inside the seed, developing a chocolatey aroma and eliminating the bitterness in the beans.
References
- Hautala T. A cluster of Candida krusei infections in a haematological unit. BMC Infectious Diseases 2007, 7:97.
- Pfaller MA. Candida krusei, a multidrug-resistant opportunistic fungal pathogen: geographic and temporal trends from the ARTEMIS DISK Antifungal Surveillance Program, 2001 to 2005. J Clin Microbiol. 2008 Feb;46(2):515-21.