Debaryomyces henanensis sp. nov., a yeast species isolated from the gut of Serrognathus titanus.

Abstract

An ascomycetous yeast strain, designated CICC 33164, was isolated from the gut of Serrognathus titanus collected in the Baotianman Nature Reserve, Henan Province, central China. Molecular phylogenetic analyses showed that this strain is most closely related to two described species of the genus Debaryomyces, namely, Debaryomyces robertsiae and Debaryomyces udenii. Genetically, strain CICC 33164 differed from the type strains of these two species by only 4-5 (0.7-0.9%) nt substitutions in the D1/D2 domain, but by 15-17 (2.6-2.8%), 78-82 (10.4-11.5%) and 104-111 (15.4%) nt mismatches in the internal transcribed spacer region and the partial ACT1 and RPB2 genes. Physiologically, the novel strain can be distinguished from D. robertsiae and D. udenii by its ability to assimilate inulin and dl-lactate and by its inability to assimilate l-rhamnose or melezitose or to ferment glucose. Based on the combined phylogenetic and phenotypic evidence, strain CICC 33164 represents a novel species of the genus Debaryomyces, for which the name Debaryomyces henanensis sp. nov. is proposed.