''Hanseniaspora guilliermondii'' is a species of

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom (biology), kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are est ...

in the family

Saccharomycetaceae The Saccharomycetaceae are a family of yeasts in the order Saccharomycetales that reproduce by budding. Species in the family have a cosmopolitan distribution, and are present in a wide variety of habitats, especially those with a plentiful supp ...

. In its

anamorph In mycology, the terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota: *Teleomorph: the sexual reproductive stage (morph), typically a fruiting body. *Anamorph: an ase ...

form, it is called ''Kloeckera apis''.

Taxonomy

The initial sample of the species was isolated by South African pathologist Adrianus Pijper from an infected nail from a patient and assigned the name ''H. guilliermondii''. In 1952, the species was placed in

synonymy A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

with ''

Hanseniaspora valbyensis ''Hanseniaspora'' is a genus of yeasts. The name ''Kloeckera'' is applied to its anamorph form. They are typically apiculate (lemon-shaped) in shape and often found in grape musts pre-fermentation. The genus name ''Hanseniaspora'' honours Emil ...

''. In 1968, N. J. W. Kerger-Van Rij and Donald G. Ahearn, observed physiological and morphological differences between ''H. valbyensis'' and ''H. guilliermondii'' and proposed a resumed separation of the two species. Their study identified that a third strain, originally described as ''H. melligeri'' by J. Lodder in 1932 that had been isolated from dates and later synonymized with ''H. valbyensis'', was synonymous with ''H. guilliermondii''. Further testing by Meyer, Brown, and Smith in 1977 confirmed the findings of the 1968 study using DNA testing. Further DNA examination in 1978 demonstrated that yeast samples originally collected from grape juice and identified as the unique species ''H. apuliensis'' by Castelli in 1948, later synonymized with ''H. valbyensis'' in 1958, was actually synonymous with ''H. guilliermondii''. Yeast samples that had been obtained from a bee by P. Lavie in 1954 and later designated as ''Kloeckera apis'' was found to be the

form of ''H. guilliermondii'' and placed in synonymy.

Description

Microscopic examination of the yeast cells in YM liquid medium after 48 hours at 25°C reveals cells that are 2.2 to 5.8 μm by 4.5 to 10.2 μm in size or occasionally longer, apiculate,

ovoid An oval () is a closed curve in a plane which resembles the outline of an egg. The term is not very specific, but in some areas of mathematics (projective geometry, technical drawing, etc.), it is given a more precise definition, which may inc ...

to elongate, appearing singly or in pairs. Reproduction is by

budding Budding or blastogenesis is a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at one particular site. For example, the small bulb-like projection coming out from the yeast cell is kno ...

, which occurs at both poles of the cell. In broth culture, sediment is present, and after one month a very thin ring is formed. Colonies that are grown on malt agar for one month at 25°C appear white to cream-colored, glossy, and smooth. Growth is slightly raised at the center. The yeast forms poorly-developed

pseudohyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one o ...

on potato agar, or are absent. The yeast has been observed to form one to four, mostly four, hat-shaped

ascospores In fungi, an ascospore is the sexual spore formed inside an ascus—the sac-like cell that defines the division Ascomycota, the largest and most diverse division of fungi. After two parental nuclei fuse, the ascus undergoes meiosis (halving of ...

when grown for at least one week on 5% Difco malt extract agar or on potato dextrose agar. When released, the ascospores tend to clump together. The yeast can ferment

glucose Glucose is a sugar with the Chemical formula#Molecular formula, molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae d ...

, but not

galactose Galactose (, ''wikt:galacto-, galacto-'' + ''wikt:-ose#Suffix 2, -ose'', ), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweetness, sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epime ...

sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined ...

maltose } Maltose ( or ), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the tw ...

lactose Lactose is a disaccharide composed of galactose and glucose and has the molecular formula C12H22O11. Lactose makes up around 2–8% of milk (by mass). The name comes from (Genitive case, gen. ), the Latin word for milk, plus the suffix ''-o ...

raffinose Raffinose is a trisaccharide composed of galactose, glucose, and fructose. It can be found in beans, cabbage, brussels sprouts, broccoli, asparagus, other vegetables, and whole grains. Raffinose can be hydrolyzed to D-galactose and sucrose by th ...

trehalose Trehalose (from Turkish '' tıgala'' – a sugar derived from insect cocoons + -ose) is a sugar consisting of two molecules of glucose. It is also known as mycose or tremalose. Some bacteria, fungi, plants and invertebrate animals synthesize it ...

. It has a positive growth rate at 37°C, but no growth at 40°C. It can grow on agar media containing 0.1%

cycloheximide Cycloheximide is a naturally occurring fungicide produced by the bacterium '' Streptomyces griseus''. Cycloheximide exerts its effects by interfering with the translocation step in protein synthesis (movement of two tRNA molecules and mRNA in re ...

and utilize 2-keto-d-gluconate as a sole source of carbon.

Ecology

Although the original sample of the species was obtained in a clinical medical setting, the yeast is primarily associated with fruits, plants, fermenting musts, and insects. Strains of this species produce

acetoin Acetoin, also known as 3-hydroxybutanone or acetyl methyl carbinol, is an organic compound with the formula CH3CH(OH)C(O)CH3. It is a colorless liquid with a pleasant, buttery odor. It is chiral. The form produced by bacteria is (''R'')-acetoin. ...

, a chemical found in many food products and fragrances.

References

{{Taxonbar, from=Q10517385 Saccharomycetes Yeasts Fungi described in 1928 Fungus species