| Lachancea kluyveri | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Saccharomycetes |
| Order: | Saccharomycetales |
| Family: | Saccharomycetaceae |
| Genus: | Lachancea |
| Species: | L. kluyveri |
| Binomial name | |
| Lachancea kluyveri (Phaff, M.W.Mill. & Shifrine) Kurtzman (2003) | |
| Synonyms | |
| |
Lachancea kluyveri is an ascomycetous yeast associated with fruit flies, slime fluxes, soils and foods.
The habitat of L. kluyveri is not well known because only about 30 isolates have been recorded. It is, however, thought to be environmentally widespread. First described as Saccharomyces kluyveri in 1956 from fruit flies in California, [1] this species has been isolated from slime fluxes on tree, soils in North America and Europe, [2] [3] and cheeses. [4] It has also been reported as an agent of disseminated mycosis in a patient with HIV/AIDS. [5]
Lachancea kluyveri is a budding yeast related to Saccharomyces cerevisiae , or baker's yeast, the model organism intensively used in biochemistry, genetics and cell biology. In 2003 it was transferred from the genus Saccharomyces to the genus Lachancea named for Canadian mycologist and yeast biologist Marc-André Lachance. [6] Saccharomyces cerevisiae and L. kluyveri have several fundamental differences that warrant genomic comparisons. First, like most cell types, L. kluyveri resorts to fermentation (degrading sugars in the absence of oxygen) only when oxygen is limiting. S. cerevisiae, on the other hand, prefers to carry out fermentation even in the presence of oxygen. This means that L. kluyveri makes a more efficient use of glucose for energy production. Therefore, L. kluyveri provides a contrasting model to one of the most unusual features of S. cerevisiae. Second, L. kluyveri has a simpler genome organization than S. cerevisiae: it appears to have become a species before the whole genome duplication that occurred in the Saccharomyces lineage. As a result, its genome is smaller (about 9.5 million base pairs) than that of S. cerevisiae with fewer duplicated genes. Additionally, L. kluyveri is becoming more widely used as a model organism and for industrial applications, such as the production of proteins, since its biomass yield is greater than that of S. cerevisiae due to more efficient use of glucose. [7]
| NCBI genome ID | 69 |
|---|---|
| Ploidy | diploid |
| Genome size | 12.6 Mb |
| Number of chromosomes | 8 pairs |
| Year of completion | 2002 |
The L. kluyveri genome was originally sequenced in 2002 to approximately 3.5× whole genome shotgun (WGS) coverage. [7]
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Saccharomyces cerevisiae is a species of yeast. The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have been originally isolated from the skin of grapes. 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 budding.
In cooking, syrup is a condiment that is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars but showing little tendency to deposit crystals. In its concentrated form, its consistency is similar to that of molasses. The viscosity arises from the multiple hydrogen bonds between the dissolved sugar, which has many hydroxyl (OH) groups.
Schizosaccharomyces pombe, also called "fission yeast", is a species of yeast used in traditional brewing and as a model organism in molecular and cell biology. It is a unicellular eukaryote, whose cells are rod-shaped. Cells typically measure 3 to 4 micrometres in diameter and 7 to 14 micrometres in length. Its genome, which is approximately 14.1 million base pairs, is estimated to contain 4,970 protein-coding genes and at least 450 non-coding RNAs.
A facultative anaerobic organism is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation if oxygen is absent.
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Saccharomyces boulardii is a tropical yeast first isolated from lychee and mangosteen fruit peel in 1923 by French scientist Henri Boulard. Although early reports claimed distinct taxonomic, metabolic, and genetic properties, S. boulardii is genetically a grouping of S. cerevisiae strains, sharing >99% genomic relatedness, giving the synonym S. cerevisiae var. boulardii.
Kluyveromyces marxianus in ascomycetous yeast and member of the genus, Kluyveromyces. It is the sexual stage of Atelosaccharomyces pseudotropicalis also known as Candida kefyr. This species has a homothallic mating system and is often isolated from dairy products.
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The Crabtree effect, named after the English biochemist Herbert Grace Crabtree, describes the phenomenon whereby the yeast, Saccharomyces cerevisiae, produces ethanol (alcohol) in aerobic conditions at high external glucose concentrations rather than producing biomass via the tricarboxylic acid (TCA) cycle, the usual process occurring aerobically in most yeasts e.g. Kluyveromyces spp. This phenomenon is observed in most species of the Saccharomyces, Schizosaccharomyces, Debaryomyces, Brettanomyces, Torulopsis, Nematospora, and Nadsonia genera. Increasing concentrations of glucose accelerates glycolysis which results in the production of appreciable amounts of ATP through substrate-level phosphorylation. This reduces the need of oxidative phosphorylation done by the TCA cycle via the electron transport chain and therefore decreases oxygen consumption. The phenomenon is believed to have evolved as a competition mechanism around the time when the first fruits on Earth fell from the trees. The Crabtree effect works by repressing respiration by the fermentation pathway, dependent on the substrate.
D-Xylose is a five-carbon aldose that can be catabolized or metabolized into useful products by a variety of organisms.
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Saccharomyces eubayanus, a cryotolerant type of yeast, is most likely the parent of the lager brewing yeast, Saccharomyces pastorianus.
Aerobic fermentation or aerobic glycolysis is a metabolic process by which cells metabolize sugars via fermentation in the presence of oxygen and occurs through the repression of normal respiratory metabolism. Preference of aerobic fermentation over aerobic respiration is referred to as the Crabtree effect in yeast, and is part of the Warburg effect in tumor cells. While aerobic fermentation does not produce adenosine triphosphate (ATP) in high yield, it allows proliferating cells to convert nutrients such as glucose and glutamine more efficiently into biomass by avoiding unnecessary catabolic oxidation of such nutrients into carbon dioxide, preserving carbon-carbon bonds and promoting anabolism.
Lachancea thermotolerans is a species of yeast.
Hanseniaspora occidentalis is a species of yeast in the family Saccharomycetaceae. In its anamorph form, it was called Kloeckera javanica. It has been isolated in the wild from soil samples and vineyards. Samples of a variant have been isolated from orange juice and rotten oranges. It has demonstrated potential as an organism to reduce malic acid in wine production.
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