Dipodascus
tetrasporeus
Nagah. & Abdel-Wahab, International Journal of Systematic and Evolutionary Microbiology 58 (4): 1040-1046 (2008)
Saccharomycetes, Subclass Saccharomycetidae
Saccharomycetales
Dipodascaceae
Dipodascus Lagerh., Jahrbücher für Wissenschaftliche Botanik 24: 549 (189
Type species:
Dipodascus albidus Lagerh., Jahrbücher für Wissenschaftliche Botanik 24: 549-565 (1892)
Marine species:
Dipodascus tetrasporeus Nagah. & Abdel-Wahab, International Journal of Systematic and Evolutionary Microbiology 58 (4): 1040-1046 (2008)
Index Fungorum Number: 533142 Faceoffungi Number: N/A
After 10 days on MEYE agar at 20°C, colonies are 25–30 mm in diameter, white, flat, dry, centrally powdery and swelling, with finely hairy margins. Hyphae are 3–5 µm wide, with rounded apices, and with some basitonous branching, with slight differentiation between main and lateral branches, branches soon disarticulating into cylindrical arthroconidia (2.5–4.0-5.0–36.0 µm). Abundant true mycelia and arthroconidia are formed. On ME agar medium, hyphae and arthroconidia produce clusters of globose to subglobose blastospores, 4.0–6.0 µm in diameter. Gametangia are located on opposite sides of septa or on separate hyphae. Asci are subspherical to broadly ellipsoidal, 5–10 µm wide and 6–14 µm long, and contain one to four ascospores. Ascospores are globose to subglobose 3.0–5.0 µm in diameter, with an irregular exosporium and gelatinous sheath. The species is homothallic. D-glucose and galactose are fermented but sucrose, maltose, lactose, raffinose and melibiose are not. The following carbon compounds are assimilated: D-glucose, galactose, L-sorbose, D-xylose, D-arabinose (weak), D-ribose (weak), ethanol, glycerol, glucono- b-lactone, DL-lactic acid, succinic acid and D-galacturonic acid. No growth occurs on sucrose, maltose, cellobiose, trehalose, lactose, melibiose, raffinose, melezitose, inulin, soluble starch, L-arabinose, L-rhamnose, erythritol, ribitol, galactitol, D-mannitol, D-glucitol, methyl a-D-glucoside, salicin, 2-ketogluconic acid, 5-ketogluconic acid, citric acid, inositol or D-glucuronic acid. The nitrogen compounds ethylamine, lysine and cadaverine are assimilated but potassium nitrate and sodium nitrite are not. Growth occurs at 27°C and is weak at 30°C but does not occur at all at 33°C on MEYE agar. Growth occurs on vitamin-free medium. No growth occurs on 50% glucose/yeast extract agar. Growth occurs in the presence of 100 p.p.m. cycloheximide. No growth occurs in the presence of 10% sodium chloride. No starch-like substances are produced. The diazonium blue B reaction is negative. Urease activity is negative. The G+C content of the nuclear DNA is 40.7 mol% (by HPLC).
Description based on Nagahama et al. (2008).
Key references:
Nagahama T, Abdel–Wahab MA, Nogi Y, Miyazaki M, Uematsu K, Hamamoto M, Horikoshi K (200). Dipodascus tetrasporeus sp. nov., an ascosporogenous yeast isolated from deep–sea sediments in the Japan Trench. International Journal of Systematic and Evolutionary Microbiology. 58(4):1040–1046.