Fonsecazyma yulaniae sp. nov., a yeast species isolated from flowers

Abstract

Two basidiomycete yeast strains, designated as 21S12 and 12S11, were isolated from the flowers of Yulania denudata collected from the Beijing Olympic Forest Park, PR China. Molecular phylogenetic analyses based on the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) region revealed that these strains represent a novel species within the genus Fonsecazyma. The new species, Fonsecazyma yulaniae sp. nov., is most closely related to Fonsecazyma mujuensis CBS 10308^T, with sequence divergences of 4.3% (28 substitutions and 2 indels) in the D1/D2 domain and 8.4% (28 substitutions and 10 indels) in the ITS region. Phenotypically, F. yulaniae sp. nov. differs from F. mujuensis CBS 10308^T in its ability to assimilate inulin and creatinine, as well as its inability to assimilate lactose and erythritol. Additionally, F. yulaniae sp. nov. can grow in a vitamin-free medium and in a medium supplemented with 50% glucose, conditions under which F. mujuensis cannot grow. The holotype of F. yulaniae sp. nov. is CGMCC2.5852^T, and its taxonomic description has been registered in Fungal Names (FN572294) and in Mycobank (MBT10026390).

Keywords: Fonsecazyma; flower; novel species; phylogeny.

Fig. 1.. ML phylogenetic tree based on concatenated sequences of the D1/D2 domains of the LSU rRNA gene and the ITS region, showing the phylogenetic placement of F. yulaniae sp. nov. among related genera. Bootstrap values ≥50% (from 1,000 replicates) are indicated at the nodes. Filled circles represent nodes supported by all three methods: ML, NJ and MP. C. amylolentus CBS 6039^T was used as the outgroup. Bar, 0.02 substitutions per nt position.

Fig. 2.. Cell morphology of F. yulaniae sp. nov. 21S12^T observed by optical microscope (a) and SEM (b) after 3 days of growth at 25 °C in YM broth.