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Masako Takashima

Publications and source records attributed to Masako Takashima.

13 recordsLinked to original sources
PubMed2003

Bullera anomala sp. nov. and Bullera pseudovariabilis sp. nov., two new ballistoconidium-forming yeast species from Yunnan, China.

Two ballistoconidium-forming yeast strains, CH 2.504 and CH 2.509, were isolated from the wilting leaves of Parthenocissus sp. collected in Yunnan, China in 1996. These two strains were assigned to the genus Bullera Derx by the characteristics of forming rotationally symmetric ballistoconidia, containing xylose in the cell hydrolysates and having Q-10 as the major ubiquinone. Molecular phylogenetic analysis based on small subunit ribosomal RNA gene (18S rDNA) and internal transcribed spacer (ITS) region sequences revealed that CH 2.504 is closely related to B. variabilis Nakase & Suzuki, while CH 2.509 is located in a clearly separate clade among the described Bullera species and related taxa. The results indicated that CH 2.509 represents a new species, for which Bullera anomala sp. nov. is the proposed name (type strain AS 2.2094T). Further DNA-DNA reassociation data showed that CH 2.504 also represents a distinct species, for which the name Bullera pseudovariabilis sp. nov. is given (type strain AS 2.2092T).

Basidiomycota↗
PubMed2003

Three new combinations from the Cryptococcus laurentii complex: Cryptococcus aureus, Cryptococcus carnescens and Cryptococcus peneaus.

Fifteen strains of the Cryptococcus laurentii complex were reclassified based on sequence analyses of 18S rDNA, the D1/D2 region of the 26S rDNA and the internal transcribed spacer regions, as well as physiological and biochemical properties. The strains were divided into phylogenetic groups I and II. The type strain of C. laurentii (CBS 139T=ATCC 18803T=JCM 9066T=MUCL 30398T=NRRL Y-2536T) was in phylogenetic group I. Phylogenetic group II, which was phylogenetically distant from phylogenetic group I, clustered with Cryptococcus dimennae and Bullera globispora. In phylogenetic group I, the type strain of Torula aurea (CBS 318T=ATCC 32063T=IFO 0372T=NRRL Y-1582T) appeared to be a separate species from C. laurentii, and the designation Cryptococcus aureus comb. nov. is proposed for Torula aurea. Cryptococcus flavescens (formerly Torula flavescens, type strain CBS 942T=ATCC 10668T=DBVPG 6007T=MUCL 30414T) was treated as a synonym of C. laurentii; however, this is a distinct species. The type strains of Torulopsis carnescens (CBS 973T=ATCC 32064T=MUCL 30641T=NRRL Y-1503T), Rhodotorula peneaus (CBS 2409T=ATCC 13546T=MUCL 30643T=NRRL Y-2005T) and Cryptococcus victoriae belonged to phylogenetic group II. Two new combinations, Cryptococcus carnescens comb. nov. (type strain CBS 973T=ATCC 32064T=MUCL 30641T=NRRL Y-1503T) and Cryptococcus peneaus comb. nov. (type strain CBS 2409T=ATCC 13546T=MUCL 30643T=NRRL Y-2005T), are proposed from this group.

Base Composition↗
PubMed2003

The first isolation of ustilaginomycetous anamorphic yeasts, Pseudozyma species, from patients' blood and a description of two new species: P. parantarctica and P. thailandica.

The genus Pseudozyma is ustilaginomycetous anamorphic yeasts, and are mainly isolated from plants. We isolated three Pseudozyma strains from the blood of patients in Thailand. While one isolate was identified as P. antarctica by rDNA sequence analysis, the other two were considered to be new species and were named P. parantarctica and P. thailandica. The three isolates proved to be resistant to 5-flucytosine, and P. thailandica was also resistant to fluconazole and itraconazole. As far as we know, this is the first isolation of Pseudozyma strains from humans. The two new species are described.

Base Sequence↗
PubMed2002

Udeniomyces pannonicus sp. nov., a ballistoconidium-forming yeast isolated from leaves of plants in Hungary.

Fifteen ballistoconidium-forming yeasts, isolated from the leaves of plants in Hungary, showed morphological, physiological and biochemical characteristics similar to those of Udeniomyces pyricola. The identical sequences of internal transcribed spacer regions for selected strains (HY-16T, HY-29, HY-111 and HY-186) indicated that they should be classified as one species. Although a representative strain, HY-16T, showed a closer relationship to Itersonilia perplexans than to known Udeniomyces species in phylogenetic trees constructed using 18S rDNA and the D1/D2 region of the 26S rDNA sequence, this species was placed in the genus Udeniomyces on the basis of its morphological and chemotaxonomic characteristics. Udeniomycespannonicus sp. nov. (type strain HY-16T = JCM 11145T = NCAIM Y 01556T = CBS 9123T) is proposed.

Base Composition↗
PubMed2002

Reclassification of the Sporobolomyces roseus and Sporidiobolus pararoseus complexes, with the description of Sporobolomyces phaffii sp. nov.

More than 50 ballistoconidium-forming yeast strains, isolated from plant leaves collected in Yunnan, China, were identified as Sporobolomyces roseus Kluyver & van Niel by conventional methods. However, comparison of the internal transcribed spacer (ITS) region and 265 rDNA D1/D2 domain sequences indicated that these strains represented more than one species. Type or authentic strains of the synonyms of Sporobolomyces roseus and the closely related species Sporidiobolus pararoseus Fell & Tallman were employed in the rDNA sequence comparison. Sporobolomyces boleticola Ramírez, Sporobolomyces pollaccii Verona & Ciferri, Sporobolomyces roseus var. madurae Janke and Torulopsis somala Verona were confirmed to be conspecific with Sporobolomyces roseus. Another synonym of this species, Sporobolomyces salmoneus Derx, was located together with Sporobolomyces marcillae Santa Maria in a separate clade. Two synonyms of Sporidiobolus pararoseus, Sporobolomyces carnicolor Yamasaki & Fujii (nom. inval.) and Sporobolomyces japonicus Iizuka & Goto, were revealed to represent two distinct species. The name Sporobolomyces carnicolor is validated, with strain CBS 4215(T) as the type strain. A novel species represented by five of the selected Yunnan strains was confirmed, for which the name Sporobolomyces phaffii sp. nov. is proposed (type strain CH 2.052(T) = AS 2.2137(T) = JCM 11491(T) = CBS 9129(T)). This study also indicates that yeast species with similar ITS sequences may have quite different D1/D2 sequences.

Base Sequence↗
PubMed2002

New yeast species, Malassezia dermatis, isolated from patients with atopic dermatitis.

Malassezia species are considered to be one of the exacerbating factors in atopic dermatitis (AD). During examination of the cutaneous colonization of Malassezia species in AD patients, we found a new species on the surface of the patients' skin. Analysis of ribosomal DNA sequences suggested that the isolates belonged to the genus MALASSEZIA: They did not grow in Sabouraud dextrose agar but utilized specific concentrations of Tween 20, 40, 60, and 80 as a lipid source. Thus, we concluded that our isolates were new members of the genus Malassezia and propose the name Malassezia dermatis sp. nov. for these isolates.

DNA, Ribosomal↗
PubMed2002

Dioszegia zsoltii sp. nov., a new ballistoconidium-forming yeast species with two varieties.

As a result of conventional characterization of yeasts isolated from various plant leaves collected in Yunnan, China, six ballistoconidium-forming strains with orange-colored colonies were grouped together. Molecular phylogenetic analysis based on 18S rDNA sequencing showed that two representative strains of this group of yeasts, CH 2.068 and CH 2.497, were closely related to the species in the genus Dioszegia and had signature sequences typical of this genus. However, the six strains from Yunnan differed from the described Dioszegia species remarkably (14.5-17.7% nucleotide divergences) in the ITS (internal transcribed spacer) region sequences, which indicated that they represent a distinct species. Furthermore, among the six strains studied, the ITS region sequence comparison allowed the recognition of two subgroups represented by CH 2.068 and CH 2.497, which differ from each other in three bases in the ITS 2 region. DNA-DNA relatedness revealed that the two subgroups represent two varieties of a new species in the genus Dioszegia, for which Dioszegia zsoltii sp. nov. var. zsoltii and Dioszegia zsoltii var. yunnanensis var. nov. are proposed.

Base Sequence↗
PubMed2002

Bullera taiwanensis sp nov and Bullera formosensis sp nov, two new ballistoconidium-forming yeast species isolated from plant leaves in Taiwan.

Two strains of ballistoconidiogenous yeasts that contain xylose and form Q-10 ubiquinone were isolated from plant leaves collected in Taiwan and were found to represent two new species. The taxonomic properties of both coincide with the genus Bullera so they are described as Bullera taiwanensis sp. nov. and Bullera formosensis sp. nov. In a phylogenetic tree based on the nucleotide sequences of 18S ribosomal DNAs, these two species are distant from the clusters where the remaining members of the genus Bullera are located, i.e., Bullera taiwanensis is located in the Filobasidium lineage (Filobasidiales clade) and Bullera formosensis is located in the Cryptococcus humicola-Trichosporon lineage (Trichosporonales clade).

Basidiomycota↗
PubMed2001

Emendation of Dioszegia with redescription of Dioszegia hungarica and two new combinations, Dioszegia aurantiaca and Dioszegia crocea.

During phylogenetic analyses of hymenomycetous yeasts based on 18S rDNA sequences, we found that Bullera armeniaca showed an extremely close phylogenetic relationship to Cryptococcus hungaricus. The analyses of internal transcribed spacer (ITS) regions of the two yeasts and the phylogenetically related species, Bullera aurantiaca and Bullera crocea, showed that B. armeniaca and C. hungaricus had identical sequences, indicating that these were conspecific. B. aurantiaca and B. crocea also showed high sequence similarity, 97.1% for ITS1, 100% for ITS2, and 98.7% for overall ITS regions. A DNA-DNA reassociation experiment revealed that B. armeniaca and C. hungaricus were conspecific and B. aurantiaca and B. crocea were two distinct species. These species occurred at a phylogenetically different lineage from that of Bulleromyces albus (anamorph: Bullera alba, type species of Bullera) and Filobasidiella neoformans (anamorph: Cryptococcus neoformans, neotype species of Cryptococcus). Based on these results, we emend the genus Dioszegia to include both ballistoconidium-forming and non-ballistoconidium-forming yeasts and redescribe the species Dioszegia hungarica. B. aurantiaca and B. crocea are also transferred to Dioszegia as Dioszegia aurantiaca comb. nov. and Dioszegia crocea comb. nov.

Journal Article↗
PubMed2000

Four new species of Kockovaella isolated from plant leaves collected in Vietnam.

Five ballistoconidiogenous yeast strains, isolated from plant leaves at Cuc Phuong National Forest of Ninh Binh, Vietnam, were assigned to the genus Kockovaella based on morphological and chemotaxonomical characteristics. They represent four new species based on analyses of 18S rDNA sequence, sequences of internal transcribed spacer regions, and DNA-DNA reassociation experiments. Four new species, Kockovaella calophylli (1 strain), Kockovaella cucphuongensis (2 strains), Kockovaella litseae (1 strain), and Kockovaella vietnamensis (1 strain) are proposed for these strains.

Journal Article↗
PubMed1998

Three new species of Kockovaella isolated from plants collected in the Ogasawara Islands.

Five strains of unknown ballistoconidiogenous yeasts, which were isolated from plant leaves collected in the Ogasawara Islands, Japan, were taxonomically studied. They represent three different species of the genus Kockovaella based on morphological, physiological and biochemical characteristics, analysis of small subunit ribosomal RNA gene sequences, and DNA-DNA reassociation experiments. Three new species, Kockovaella machilophila (1 strain), Kockovaella phaffii (3 strains) and Kockovaella schimae (1 strain) are proposed for these five strains.

Journal Article↗