Sporobolomyces inositophilus,a new species of ballistosporous yeast isolated from a dead leaf of Sasa sp. in Japan

A new species of ballistosporous yeast, Sporobolomyces inositophilus was isolated from a dead leaf of Sasa sp. collected at a mountain in Japan. This yeast is assumed to have a close relationship to Sporobolomyces singularis since it produces bilaterally symmetrical ballistospores and pale-coloured colonies and resembles Sporobolomyces singularis in these respects. These two species differ from typical species of Sporobolomyces and seem to constitute a natural taxonomic group.     

Sporobolomyces diospyroris sp. nov., Sporobolomyces lophatheri sp. nov. and Sporobolomyces pyrrosiae sp. nov., three new species of ballistoconidium-forming yeasts in the Agaricostilbum lineage isolated from plants in Taiwan

Three strains of xylose-lacking and ubiquinone-10-having ballistoconidium-forming yeasts isolated from plant leaves collected in Taiwan were found to represent respective new species. In phylogenetic trees constructed based on the nucleotide sequences of 18S rDNA and D1/D2 domain of 26S rDNA, they were located in the Agaricostilbum lineage (Agaricostilbum/Bensingtonia cluster). Since the taxonomic properties of these species coincide with those of the genus Sporobolomyces, they are described as Sporobolomyces diospyroris sp. nov., Sporobolomyces lophatheri sp. nov. and Sporobolomyces pyrrosiae sp. nov., respectively.     

Sporobolomyces magnisporus sp. nov., a new yeast species in the Erythrobasidium cluster isolated from plants in Taiwan

Two strains of yeasts that contain Q-10 as the major ubiquinone, lack cellular xylose and produce large bilaterally symmetrical ballistoconidia were isolated from plants collected in a protected subtropical rain forest in Taiwan and were found to represent a new species. The taxonomic properties of this species coincide with the genus Sporobolomyces, so it is described as Sporobolomyces magnisporus sp. nov. In phylogenetic trees based on the nucleotide sequences of 18S ribosomal DNA and D1/D2 domain of 26S ribosomal DNA, this species is located in the Erythrobasidium cluster.     

Sporobolomyces salmonicolor var. fischerii,a new yeast

A new variety of Sporobolomyces salmonicolor, a basidiomycetous yeast isolated from the cerebrospinal fluid of a human case of meningitis has been described. The variety can be differentiated from the species primarily by its ability to assimilate D-galactose and L-arabinose.     

Four new yeast species of the genus Sporobolomyces from plant leaves

Among the ballistoconidium-forming yeast strains isolated from various plant leaves collected in North and Northeast China, 12 strains forming orange to orange-red colored colonies were revealed to represent four novel species of the genus Sporobolomyces by conventional, chemotaxonomic and molecular phylogenetic studies, based on the 26S-rDNA D1/D2 domain and internal transcribed spacer (ITS) region sequences. Sporobolomyces beijingensis sp. nov., represented by eight strains (type strain CB 80T = AS 2.2365T = CBS 9730T), and Sporobolomyces jilinensis sp. nov., represented by two strains (type strain CB 118T = AS 2.2301T = CBS 9728T), clustered in the Johnsonii clade of the Sporidiobolus lineage. Sporobolomyces clavatus sp. nov., represented by strain CB 281T (= AS 2.2318T = CBS 9729T), belonged to the Agaricostilbum lineage and showed a close relationship to Sporobolomyces ruber and Sporobolomyces dracophylli. Sporobolomyces symmetricus sp. nov., represented by strain CB 64T(= AS 2.2299T = CBS 9727T), formed nearly symmetrical ballistoconidia and was closely related with Sporobolomyces vermiculatus and Sporobolomyces gracilis in the Gracilis clade of the Erythrobasidium lineage.     

Sporobolomyces yuccicola,a new species of ballistosporous yeast equipped with ubiquinone-9

A hitherto undescribed ballistosporous yeast was isolated from a dead leaf of Yucca sp. in Canada. This yeast produces apiculate or short-ellipsoidal ballistospores, produces pale colored colonies, has Q-9 as the major ubiquinone, and does not contain xylose in the cells. This new yeast is described as Sporobolomyces yuccicola Nakase et Suzuki. Sporobolomyces yuccicola is the sixth species of the intermedius group, a group of atypical species of the genus Sporobolomyces equipped with Q-9.     

Heterothallism in the basidiomycetous yeast genusSporidiobolus Nyland

The sexual speciesSporidiobolus salmonicolor andSporidiobolus pararoseus spp. nov. are described as heterothallic species in the genusSporidiobolus, a genus consisting of two homothallic species,Sporidiobolus johnsonii andSporidiobolus ruinenii. The four species are compared and a key to the genus is presented. As a taxonomic correctionSporobolomyces pararoseus nom. nud. is reported as a synonym ofSporobolomyces shibatanus.     

Nucleotide Composition of Deoxyribonucleic Acid of Some Species of Cryptococcus, Rhodotorula, and Sporobolomyces

The buoyant density of deoxyribonucleic acid (DNA) from nine species and two varieties of Cryptococcus, three species and two varieties of Rhodotorula, and six species of Sporobolomyces was determined by CsCl density gradient equilibrium centrifugation. Several species were represented by two to four different strains. Expressed in moles per cent of guanine plus cytosine (GC content) the ranges were 49 to 65%, 52 to 70%, and 51 to 65% for Cryptococcus, Rhodotorula, and Sporobolomyces, respectively. For each genus, the GC content was distributed into two discrete groups with averages ranging from 52 to 54 and 60 to 66, respectively. An analysis of these results suggested that the determination of GC content of DNA had a taxonomic value for these yeast genera.     

Four new species of yeast isolated from insect frass in bark ofTsuga heterophylla (Raf.) Sargent

Summary In a study of the yeasts associated with insect frass underneath the bark ofTsuga heterophylla (the Pacific Coast hemlock) four new species of yeast were found. These were described asSporobolomyces singularis, Bullera tsugae, Cryptococcus skinneri andCandida oregonensis. Sporobolomyces singularis is a non-pigmented species, which required an amendment of the genus definition. Ballistospore formation of the new species ofSporobolomyces and ofBullera was absent on malt agar and on potato glucose agar, but positive on corn meal agar. An unusual case of quantitative transgalactosylation by growing cells ofSporobolomyces singularis on lactose has been described. It has been proposed to establish a “Candida parapsilosis Group” of species to whichC. oregonensis was assigned. Supported by a fellowship of the Calouste Gulbenkian Foundation, Lisbon, Portugal.     

掷孢菌科的研究 Ⅱ.中国叶表掷孢酵母的初步分类及掷孢酵母属的种类

作者多年来从我国禾本科等植物叶表分离了大量掷孢酵母,本文重点报道70株掷孢酵母与类酵母的初步分类,共分为三属,即掷孢酵母属(Sporobolomyces),布勒掷孢酵母属(Bul-lera)与腥掷孢菌属(Tilletiopsis);其中掷孢酵母属占75％。至于53株掷孢酵母,共分为三种,即玫红掷孢酵母(Sporobolomyces roseus)、赭色掷孢酵母(Sporobolomyces salmonicolor)、Sporobolomyces shibatanus);经统计,后者最为常见,占此属的84％。这些种在我国尚未见报道,作为新记录。     

Production of biotin by yeasts

A quantitative screening procedure for biotin and biotin vitamer production was conducted on 129 yeast strains able to grow in a biotin-free medium. Production of biotin and biotin vitamers varied considerably from strain to strain even within a species. The best producers of biotin were strains of Sporobolomyces roseus and Rhodotorula rubra whilst strains of Rhodotorula rubra and Yarrowia lipolytica produced the largest amounts of vitamers.     

Assessment of phylloplane yeasts on selected Mediterranean plants by FISH with group- and species-specific oligonucleotide probes

A previous culture-dependent survey of phylloplane yeasts from selected Mediterranean plants showed that a few species were present in high densities in almost all leaf samples, regardless of the plant type, location or sampling season. However, a few species appeared to be restricted to Cistus albidus leaves, namely Cryptococcus cistialbidi . Here, we describe a culture-independent FISH assay to detect and quantify whole yeast cells in leaf washings. After optimization, the technique was used to check the apparent association between C. albidus leaves and C. cistialbidi and the abundance and ubiquity of other basidiomycetous yeast species such as Erythrobasidium hasegawianum and Sporobolomyces spp. in leaf samples from this and other neighboring plants ( Acer monspessulanum and Quercus faginea ). No yeast cells were detected in Pistacia lentiscus leaf samples. We were also able to demonstrate that three phylloplane yeasts ( C. cistialbidi, E. hasegawianum and Sporobolomyces spp.) appeared to be log-normally distributed among individual C. albidus leaves. The log-normal distribution has important implications for the quantification of phylloplane yeasts based on the washing and plating of bulk leaf samples, which will tend to overestimate the size of the respective populations and become an error source in yeast surveys or related biocontrol studies.     

Two new species of the genus Sporobolomyces and a new Rhodotorula species from leaf surfaces

Two new species of the genus Sporobolomyces and one of the genus Rhodotorula are described. Sporobolomyces elongatus and Rhodotorula armeniaca spp. nov. were isolated from the surfaces of leaves of Callistemon viminalis (Soland ex Gaertn.) G. Don ex Loud. and Sporobolomyces foliicola from the leaves of Banksia collina R. Br. growing at Armidale.     

Yeast biodiversity in hydromorphic soils with reference to grass-Sphagnum swamp in Western Siberia and the hammocky tundra region( Barrow, Alaska)]

The microbiological analysis of 78 samples taken from a boreal bog in Western Siberia and from a tundra wetland soil in Alaska showed the presence of 23 yeast species belonging to the genera Bullera, Candida, Cryptococcus, Debaryomyces, Hanseniaspora, Metschnikowia, Mrakia, Pichia, Rhodotorula, Saccharomyces, Sporobolomyces, Torulaspora, and Trichosporon. Peat samples from the boreal bog were dominated by eurytopic anamorphic basidiomycetous species, such as Rhodotorula mucilaginosa and Sporobolomyces roseus, and by the ascomycetous yeasts Candida spp. and Debaryomyces hansenii. These samples also contained two rare ascomycetous species (Candida paludigena and Schizoblastosporion starkeyi-henricii), which so far have been found only in taiga wetland soils. The wetland Alaskan soil was dominated by one yeast species (Cryptococcus gilvescens), which is a typical inhabitant of tundra soils. Therefore, geographic factors may serve for a more reliable prediction of yeast diversity in soils than the physicochemical or ecotopic parameters of these soils.     

Development of resources for the analysis of gene function in Pucciniomycotina red yeasts

The Pucciniomycotina is an important subphylum of basidiomycete fungi but with limited tools to analyze gene functions. Transformation protocols were established for a Sporobolomyces species (strain IAM 13481), the first Pucciniomycotina species with a completed draft genome sequence, to enable assessment of gene function through phenotypic characterization of mutant strains. Transformation markers were the URA3 and URA5 genes that enable selection and counter-selection based on uracil auxotrophy and resistance to 5-fluoroorotic acid. The wild type copies of these genes were cloned into plasmids that were used for transformation of Sporobolomyces sp. by both biolistic and Agrobacterium-mediated approaches. These resources have been deposited to be available from the Fungal Genetics Stock Center. To show that these techniques could be used to elucidate gene functions, the LEU1 gene was targeted for specific homologous replacement, and also demonstrating that this gene is required for the biosynthesis of leucine in basidiomycete fungi. T-DNA insertional mutants were isolated and further characterized, revealing insertions in genes that encode the homologs of Chs7, Erg3, Kre6, Kex1, Pik1, Sad1, Ssu1 and Tlg1. Phenotypic analysis of these mutants reveals both conserved and divergent functions compared with other fungi. Some of these strains exhibit reduced resistance to detergents, the antifungal agent fluconazole or sodium sulfite, or lower recovery from heat stress. While there are current experimental limitations for Sporobolomyces sp. such as the lack of Mendelian genetics for conventional mating, these findings demonstrate the facile nature of at least one Pucciniomycotina species for genetic manipulation and the potential to develop these organisms into new models for understanding gene function and evolution in the fungi.