Vishniacozyma melezitolytica Q.M. Wang, F.Y. Bai & A.H. Li sp. nov. 2020
MycoBank MB828742
Holotype: China, Hebei province, obtained from a leaf of an unidentified plant, Apr. 2007, Q.-M. Wang (holotype CGMCC 2.3472T preserved in a metabolically inactive state, ex-type CBS 15490 = H5A3).
Physiological and biochemical characteristics: Glucose fermentation is absent. Glucose, galactose, L-sorbose (variable), sucrose, maltose, cellobiose, trehalose, lactose, raffinose, melezitose, inulin (variable), D-xylose, L-arabinose, D-arabinose (variable), D-ribose (variable), L-rhamnose, N-Acetyl-D-glucosamine (variable), D-glucosamine (variable), ethanol, glycerol, ribitol (variable), galactitol (variable), D-mannitol, D-glucitol (variable), Methyl-α-D-glucoside (variable), salicin (weak), succinate (variable) and myo-inositol (variable) are assimilated as sole carbon sources. Melibiose, soluble starch, methanol, erythritol, D-gluconate, DL-lactate, citrate and hexadecane are not assimilated. Ammonium sulfate, potassium nitrate (variable), L-lysine, ethylamine hydrochloride (variable) and cadaverine dihydrochloride (variable) are assimilated as sole nitrogen sources. Sodium nitrite is not assimilated. Maximum growth temperature is 30 °C. Growth in vitamin-free medium is variable. Starch-like substances are not produced. Growth on 50 % (w/w) glucose-yeast extract agar is negative. Urease activity is positive. Diazonium Blue B reaction is positive.
Physiologically, V. melezitolytica differs from the closely related species V. dimennae and V. globispora in its inability to assimilate DL-lactate and citrate and its ability to assimilate melezitose (Table S1.4). Culture characteristics: In YM broth, after 7 d at 17 °C, cells are ellipsoidal, 2.6–5.0 × 3.9–6.1 μm and single, budding is polar (Fig. 7H), a sediment is formed. After 1 mo at 17 °C, a pellicle and a sediment are present. On YM agar, after 1 mo at 17 °C, the streak culture is brownish-cream, butyrous, glistening and smooth.
Habitat: unidentified plant
Distribution China,
GenBank Accession: 18S+ITS+D1/D2 MK050330\ MK050331\ MK050332 RPB1 MK849177\ MK849156 RPB2 MK849315\ MK849295 TEF1 MK849046
Reference: Nearly 500 basidiomycetous yeast species were accepted in the latest edition of The Yeasts: A Taxonomic Study published in 2011. However, this number presents only the tip of the iceberg of yeast species diversity in nature. Possibly more than 99 % of yeast species, as is true for many groups of fungi, are yet unknown and await discovery. Over the past two decades nearly 200 unidentified isolates were obtained during a series of environmental surveys of yeasts in phyllosphere and soils, mainly from China. Among these isolates, 107 new species were identified based on the phylogenetic analyses of nuclear ribosomal DNA (rDNA) [D1/D2 domains of the large subunit (LSU), the small subunit (SSU), and the internal transcribed spacer region including the 5.8S rDNA (ITS)] and protein-coding genes [both subunits of DNA polymerase II (RPB1 and RPB2), the translation elongation factor 1-α (TEF1) and the mitochondrial gene cytochrome b (CYTB)], and physiological comparisons. Forty-six of these belong to 16 genera in the Tremellomycetes (Agaricomycotina). The other 61 are distributed in 26 genera in the Pucciniomycotina. Here we circumscribe eight new genera, three new families and two new orders based on the multi-locus phylogenetic analyses combined with the clustering optimisation analysis and the predicted similarity thresholds for yeasts and filamentous fungal delimitation at genus and higher ranks. Additionally, as a result of these analyses, three new combinations are proposed and 66 taxa are validated.
Fig. 7. Vegetative cells grown in YM broth for 5 d at 17 °C and ballistoconidia produced on corn meal agar after 7 d at 17 °C (H) V. melezitolyticum CGMCC 2.3472T ;
