Eight strains with identical sequences of the D1/D2 domains of the large subunit rRNA genes were isolated from fallen fruits in two distant localities in Laos. These strains represent a novel dimorphic budding yeast species producing invasive pseudohyphae and a brown pigment when growing on media containing quinic acid as the sole carbon source or tryptophan as the sole nitrogen source. Phylogenetic analysis of the sequences of the D1/D2 domains, the internal transcribed spacer (ITS) regions and the 18S rRNA genes placed the novel species in the Metschnikowia clade close to Candida torresii, Metschnikowia drosophilae and C andida danieliae. The taxonomic name Metschnikowia laotica f.a., sp. nov., reflecting the geographical origin of the isolates, is proposed for the novel species. The type strain is 11-524T ( = CBS 12961T = NCAIM Y.02124T = CCY 64-4-1T). The Mycobank number is MB 807383.
Several independent surveys of yeasts associated with different plant materials and soil led to the proposal of a novel yeast species belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences of the D1/D2 domains and internal transcribed spacer region of the large subunit of the rRNA gene suggested affinity to a phylogenetic lineage that includes Hannaella coprosmaensis, Hannaella oryzae and Hannaella sinensis. Thirty-two isolates were obtained from different sources, including bromeliads, nectar of Heliconia psittacorum (Heliconiaceae), flowers of Pimenta dioica (Myrtaceae), roots and leaves of sugar cane (Saccharum spp.) in Brazil, leaves of Cratoxylum maingayi, Arundinaria pusilla and Vitis vinifera in Thailand, soil samples in Taiwan, and prairie soil in the USA. Sequence analysis of the D1/D2 domains of the large subunit of the rRNA gene showed that the novel species differs from Hannaella coprosmaensis and Hannaella oryzae by 36 and 46 nt substitutions, respectively. A novel species is suggested to accommodate these isolates, for which the name Hannaella pagnoccae sp. nov. is proposed. The type strain is BI118T ( = CBS 11142T = ATCC MYA-4530T).
Two novel species, Wickerhamiella kiyanii f.a., sp. nov. (type strain FB1-1DASPT = CBS 12905T = CBMAI 1613T) and Wickerhamiella fructicola f.a., sp. nov. (type strain H10YT = CBS 12902T = CBMAI 1614T) are proposed in the Wickerhamiella clade (Saccharomycetes, Saccharomycetales) to accommodate three strains isolated from flowers and fruits typical of the Brazilian Atlantic rainforest. The novel status of these yeast species was established by sequence divergence observed in the D1/D2 domains of the LSU rRNA gene from the most closely related, described species as well as by phylogenetic analysis. Wickerhamiella kiyanii sp. nov. differs from its nearest phylogenetic neighbours W. pagnoccae CBS 12178T, Candida jalapaonensis CBS 10935T and Candida drosophilae CBS 8459T by 2.2–4.2 % in the D1/D2 sequences. By contrast, a sequence divergence of 13.2–13.8 % was observed between W. fructicola sp. nov. and its closest, described phylogenetic relative Candida kazoui JCM 12558T and Candida hasegawae JCM 12559T. Taxonomic descriptions of the two novel species are given.
A novel ustilaginomycetous yeast isolated from the intestinal tract of an insect pest of sugarcane roots in Ribeirão Preto, São Paulo State, Brazil, represents a novel species of the genus Pseudozyma based on molecular analyses of the D1/D2 rDNA large subunit and the internal transcribed spacer (ITS1+ITS2) regions. The name Pseudozyma brasiliensis sp. nov. is proposed for this species, with GHG001T ( = CBS 13268T = UFMG-CM-Y307T) as the type strain. P. brasiliensis sp. nov. is a sister species of Pseudozyma vetiver, originally isolated from leaves of vetiver grass and sugarcane in Thailand. P. brasiliensis sp. nov. is able to grow well with xylan as the sole carbon source and produces high levels of an endo-1,4-xylanase that has a higher specific activity in comparison with other eukaryotic xylanases. This enzyme has a variety of industrial applications, indicating the great biotechnological potential of P. brasiliensis.
Three yeast strains related to members of the genus Saccharomycopsis were isolated. One strain (CLIB 1310) was isolated from olive brines of fermented black olives in France and two strains (CLIB 1454 and CLIB 1455) were isolated from a plant in French Guiana. Sequence analyses based on the D1/D2 domains of the nuclear large subunit rRNA gene, small-subunit rRNA gene and partial EF-1α gene revealed that the strains represented two novel taxa exhibiting extensive sequence divergence from the previously described species of the genus Saccharomycopsis. Two novel species are described to accommodate these newly isolated strains: Saccharomycopsis olivae sp. nov. (type strain CLIB 1310T = CBS 12701T) and Saccharomycopsis guyanensis sp. nov. (type strain CLIB 1455T = CBS 12914T and strain CLIB 1454). Both strains CLIB 1454 and CLIB 1455T displayed identical sequences but differed in their ability to metabolize sorbitol and in their morphology on agar medium. Candida amapae, Candida lassensensis and Arthroascus babjevae belonging to the Saccharomycopsis clade, are reassigned to Saccharomycopsis as novel combinations.