siamensis

Type species: Kluyveromyces polysporus Van der Walt, Antonie van Leeuwenhoek 22: 271 (1956)

Marine species:

Kluyveromyces siamensis Am-in, Yongmanitchai & Limtong, FEMS Yeast Research 8 (5) (2008)

Cells spherical to ellipsoidal, proliferated by multilateral budding, and formed one to four spherical ascospores in a conjugated and evanescent ascus that may be produced parthenogenetically or by conjugation between a cell and its bud or between independent cells. Pseudohyphae were formed but true hyphae were not formed. Kluyveromyces siamensis fermented glucose, did not assimilate nitrate, gave negative results for the diazonium blue B and urease reactions and had Q-6 as the major ubiquinone as do other members of the genus Kluyveromyces. Growth in YM broth: After 3 days at 28 °C, cells are spherical to ellipsoidal (2.3–5.4 x 2.3–6.9 μm) and occur singly or in pairs. Budding is multilateral. Growth on YM agar: After 3 days at 28 °C, the streak culture is butyrous, cream-coloured, raised, with a smooth surface and has an entire margin. Formation of hyphae: Slide culture on corn meal agar after 7 days at 28 °C, pseudohyphae are formed but true hyphae are not formed. Formation of ascospores: Acospores are produced on YM agar, 5% malt extract agar, corn meal agar, Gorodkowa agar and Fowell’s acetate agar after 3 days at 28 °C. The ascus is evanescent and formed parthenogenetically or by conjugation between a cell and its bud or between independent cells. Ascospores are spherical and one to four ascospores are formed in one ascus. No pellicle is present on the surface of assimilation medium. (Description based on Am-in et al. (2008)).

Other marine species:

Kl. aestuarii (Fell) Van der Walt, Antonie van Leeuwenhoek 31: 347 (1965)

Kl. lactis var. drosophilarum (Shehata, Mrak & Phaff) G.I. Naumov, E.S.

 Naumova, Barrio & Querol, Mikrobiologiya 75(3): 299–304 (2006)

Kl. lactis var. lactis (Dombr.) Van der Walt, Bothalia 10(3): 417 (1971)

Kl. marxianus (E.C. Hansen) Van der Walt, Bothalia 10(3): 418 (1971)

Kl. nonfermentans Nagah., Hamam., Nakase & Horikoshi, Int. J. Syst. Bacteriol. 49(4): 1903 (1999)

Key references:

Am-in S, Yongmanitchai W, Limtong S (2008) Kluyveromyces siamensis sp. nov., an ascomycetous yeast isolated from water in a mangrove forest in Ranong Province, Thailand. FEMS Yeast Research. 8(5):823-828.