Fonsecazyma quercina sp. nov., a novel yeast species isolated from Persian oak (Quercus brantii Lind.) branch in Iran

Forests are yeast biodiversity hotspots. In a taxonomic study of yeast isolates collected from the Persian oak ( Quercus brantii Lind.) branch in the Zagros oak forests, Kermanshah province, Iran, one yeast isolate was found to represent a novel species. Morphological and physiological characteristics as well as sequence analysis of the D1/D2 region of the large subunit rRNA gene and the internal transcribed spacer region showed that the novel species belonged to the genus Fonsecazyma (Tremellales, Bulleraceae). The name Fonsecazyma quercina sp. nov. is proposed for this new species. Phylogenetic analysis based on D1/D2 and ITS sequences showed that strain IRAN 18507F belongs to the genus Fonsecazyma and has the highest sequence similarity with Fonsecazyma sp. KT301 (97.58%). This isolate consisted of spherical single cells and could grow up to 1 M NaCl. It grew at pH 4, 8, and 10, but not at the acidic pH of 2. The isolate is psychrotolerant, growing well between 6°C and 25°C, but not at temperatures outside this range. The isolate efficiently utilized and assimilated glucose and trehalose as carbon sources; it could also utilize sucrose, mannose, maltose, and fructose, but weakly utilized cellobiose, sorbitol, and rhamnose. This isolate could not utilize galactose, sorbose, lactose, melibiose, arabinose, ribose, or glycine as sole carbon sources. The holotype of Fonsecazyma quercina sp. nov. is IRAN 18507F (MycoBank number MB852634).