ABSTRACT
Eight yeast strains that asexually reproduce by cell fission were isolated from bee bread of different solitary bees in Germany. DNA sequence analysis revealed that the strains shared the ...same sequence in the D1/D2 domain of the nuclear large subunit (LSU) rRNA gene with a strain that was previously isolated from a fig snack from Spain. The closest related type strain was that of Schizosaccharomyces octosporus, which showed 98.2% sequence similarity (11 substitutions) with the new strains. By clone sequence analysis of the internal transcribed spacer (ITS) region (ITS1, 5.8S rDNA, and ITS2) a total of nine different copy types were identified. The new strains differed from S. octosporus by approximately 31% in the ITS region. Sequence analysis of the RNAse P gene further supported the description of a new species. The strains isolated during this study show some phenotypic characteristics that separate them from the closest related species, S. octosporus and S. cryophilus. Since all strains showed true osmophily the name of the new species is S. osmophilus (holotype: CBS 15793T; isotype: CLIB 3267 T = NCAIM Y.02225 T, MycoBank no.: MB829586).
Schizosaccharomyces osmophilus sp. nov., a true osmophilic yeast that is associated with solitary bees is described.
Six conspecific yeast strains, representing an undescribed species, were isolated from rotten wood collected in different locations in Hungary and Germany and an additional one from fungal fruiting ...body in Taiwan. The seven strains share identical nucleotide sequences in the D1/D2 domain of the nuclear large subunit (LSU) rRNA gene. The Hungarian and Taiwanese isolates share identical internal transcribed spacer (ITS) sequences as well, while the two German isolates differ from them merely by three substitutions and four indels in this region. The investigated strains are very closely related to
. Along their LSU D1/D2 domain they differ only by one substitution from the type strain of
. However, in the ITS region of Hungarian and Taiwanese strains we detected 3.5 % divergence (nine substitutions and nine indels) between the undescribed species and
, while the German strains differed by 13 substitutions and nine indels from
. This ITS sequence divergence has raised the possibility that the strains investigated in this study may represent a different species from
. This hypothesis was supported by comparisons of partial translation elongation factor 1-α (EF-1α) and cytochrome oxidase II (COX II) gene sequences. While no difference and 1-2 substitutions among the partial EF-1α and COX II gene sequences of the strains of the undescribed species, respectively, were detected; the undescribed species differ by about 4 % (36 substitutions) and 10 % (50-51 substitutions) from
in these regions. Parsimony network analysis of the partial COX II gene sequences also separated the investigated strains from the type strain of
. In this paper we propose
f.a., sp. nov. (holotype: NCAIM Y.02121; isotypes: CBS 17819, DSM 114156) to accommodate the above-noted strains.
Five yeast strains isolated from forest habitats in Hungary and Germany were characterized phenotypically and by sequencing of the D1/D2 domain of the large subunit rRNA gene and the ITS1-5.8S-ITS2 ...(ITS) region of the rRNA gene. The strains have identical D1/D2 domain and ITS region sequences. By sequence comparisons,
and
were identified as the closest relatives among the currently recognized yeast species. The DNA sequences of the investigated strains differ by 1.2 % (six substitutions) in the D1/D2 domain and by 3.5 % (12 substitutions and eight indels) in the ITS region from the type strain of
(CBS 8675
) while by 1.2 % (six substitutions and one indel) in the D1/D2 domain and by 7 % (32 substitutions and seven indels) in the ITS region from the type strain of
(CBS 5107
). Because the intraspecies heterogeneity seems to be very low and the distance to the most closely related species is above the commonly expected level for intraspecies variability
sp. nov. (holotype, CBS 16335
; isotype, NCAIM Y.02233
; MycoBank no., MB 835268) is proposed to accommodate the above-noted five yeast strains. Phenotypically the novel species can be distinguished from
and
by the formation of ascospores.
forms one or two hat-shaped ascospores per ascus on many different media as well as well-developed pseudohyphae and true hyphae. Additionally, we propose the transfer of three anamorphic members of the
sub-clade to the genus
as the following new taxonomic combinations
f.a., comb. nov.,
f.a., comb. nov. and
f.a., comb. nov.
During the course of independent studies in Europe, North America, and Africa, seven yeast strains were isolated from insect frass, decaying wood, tree flux, and olive oil sediment. Phylogenetic ...analysis of two barcoding DNA regions (internal transcribed spacer and the D1/D2 domain of the LSU rRNA gene) revealed that they belong to two closely related undescribed species distinct from all genera in the family Debaryomycetaceae. For reliable taxonomic placement the genomes of four strains of the two novel species and six type strains of closely related species were sequenced. Orthologous genes from 54 genomes of representatives of the Pichiomycetes and 23 outgroup taxa were concatenated to construct a fully supported phylogenetic tree. Consistent with the assumptions, we found that the two new species belong to a novel genus. In addition, the delimitation of the novel species was supported by genetic distance calculations from average nucleotide identity (ANI) and digital DNA:DNA hybridization (dDDH) values. The physiological characterization of the novel species was generally consistent with their genomic content. All strains had two alleles encoding secretory lipase in either two or three copies depending on the species. However, lipolytic activity was detected only in strains with three copies of the secretory lipase gene. Nevertheless, lipolytic activity might be related to their association with the insect gut. Based on these results, formal descriptions of the new genus Rasporella gen. nov. and of two new species Rasporella dianae sp. nov. (holotype UCDFST 68‐643T, MycoBank no.: 850238) and Rasporella oleae sp. nov. (holotype ZIM 2471T, MycoBank no.: 850126) are provided.
In this article, the authors describe Rasporella gen. nov. in the family Debaryomycetaceae, along with two novel species, Rasporella oleae and Rasporella dianae. The accommodation of the new genus is supported by a phylogenomic analysis involving 77 taxa. Both new species possess genes encoding secretory lipase. While one of the strains was isolated from olive oil, it was found to be a transient habitat, as most of the other strains were associated with insect frass.
Take‐away
A new genus within the Debaryomycetaceae family, Rasporella gen. nov. is described along with two new yeast species.
The accommodation of the new genus is supported by a phylogenomic analysis involving 77 taxa.
Both new species possess genes encoding secretory lipase, but only strains of Rasporella dianae exhibited the ability to degrade olive oil under laboratory conditions.
While one of the strains was isolated from olive oil, it was found to be a transient habitat, as most of the other strains were associated with insect frass.
Three strains originating from insect frass in South Africa, yellow foxglove in Hungary and soil in France, were characterised phenotypically and by sequencing of the D1/D2 domain of the large ...subunit and the ITS1-5.8S-ITS2 (ITS)-region of the rRNA gene. The strains have identical D1/D2 domain sequences and only one strain shows a 1 bp indel in a 9 bp homopolymer A/T repeat within the ITS-region. Based on sequence analysis
Hyphopichia burtonii
is the closest related species. The investigated strains differ from the type strain of
H. burtonii
by 1.9% (9 substitutions and an indel) in the D1/D2 domain and by 23 substitutions and 21–22 indels in the ITS-region. Since the sequence variability is very low among the three strains and the sequence divergence with the closely related
H. burtonii
exceeds the level generally encountered between species we propose the new species
Hyphopichia lachancei
f.a., sp. nov. to accommodate the three novel strains. From
H. burtonii
the new species can be distinguished phenotypically by its inability to ferment cellobiose and by the formation of endospores (Holotype: CBS 5999
T
; Isotype: NCAIM Y.02228
T
; MycoBank no.: MB833616).
In the course of two independent studies three yeasts have been isolated from temperate deciduous trees in Hungary and Germany. Analyses of nucleotide sequences of D1/D2 domains of the 26S rRNA gene ...(LSU) suggested that these strains belong to the Meyerozyma clade in Debaryomycetaceae (Saccharomycetales). The phylogenetic analysis of a concatenated alignment of the ITS region and LSU gene sequences confirmed the placement of the three strains in the Meyerozyma clade close to Candida elateridarum. If mixed in proper combinations, the strains formed one to two hat shaped ascospores in deliquescent asci. In addition to the ascospore formation, the three studied strains differed from Candida elateridarum and other members of the Meyerozyma clade in terms of ribosomal gene sequence and some physiological properties. To accommodate the above-noted strains, we describe the new species as Meyerozyma amylolytica sp. nov. (holotype: DSM 27310
; ex-type cultures: NCAIM Y.02140
=MUCL 56454
, allotype: NCAIM Y.01955
; ex-allotype culture: DSM 27468), MB 821663. Additionally, we propose the transfer of five non-ascosporic members of the Meyerozyma clade to the genus Meyerozyma as the following new taxonomic combinations Meyerozyma athensensis f.a., comb. nov. (MB 821664), Meyerozyma carpophila f.a., comb. nov. (MB 821665), Meyerozyma elateridarum f.a., comb. nov. (MB 821666), Meyerozyma neustonensis f.a., comb. nov. (MB 821667), and Meyerozyma smithsonii f.a., comb. nov. (MB 821668).
Six yeast strains isolated from olive oil sediments and spoiled olive oils originating from Slovenia and Portugal, respectively, proved to represent an undescribed yeast species based on DNA sequence ...comparisons. The analysis of gene sequences for internal transcribed spacer regions and the large subunit rRNA gene D1/D2 domain placed the novel species in the genus Kuraishia in a subclade containing Kuraishiacapsulata, the type species of the genus. Although the novel species is well separated genetically from the recognized species of the genus, only a minor phenotypic difference differentiating it from Kuraishia capsulata and K. molischiana was observed. Relevant to its isolation source, no lipolytic activity was detected in the strains of the novel species. To accommodate the above-noted strains, Kuraishia mediterranea sp. nov. (holotype: ZIM 2473
; isotype: CBS 15107
; MycoBank no.: MB 822817) is proposed.
Five yeast strains representing a hitherto undescribed yeast species were isolated from bee bread and honey in Hungary. They are obligate osmophilic, i.e. they are unable to grow in/on high water ...activity culture media. Following isogamous conjugation, they form 1–4 spheroid or subspheroid ascospores in persistent asci. The analysis of the sequences of their large subunit rRNA gene D1/D2 domain placed the new species in the
Zygosaccharomyces
clade. In terms of pairwise sequence similarity,
Zygosaccharomyces gambellarensis
is the most closely related species. Comparisons of D1/D2, internal transcribed spacer and translation elongation factor-1α (EF-1α) gene sequences of the five strains with that of the type strain of
Z. gambellarensis
revealed that they represent a new yeast species. The name
Zygosaccharomyces favi
sp. nov. (type strain: NCAIM Y.01994
T
= CBS 13653
T
= NRRL Y-63719
T
= ZIM 2551
T
) is proposed for this new yeast species, which based on phenotype can be distinguished from related
Zygosaccharomyces
species by its obligate osmophilic nature. Some intragenomic sequence variability, mainly indels, was detected among the ITS copies of the strains of the new species.
The systematic position of 16 yeast strains isolated from Thailand, Hungary, The Netherlands, and the Republic of Poland were evaluated using morphological, physiological, and phylogenetic analyses. ...Based on the similarity of the D1/D2 domain of the LSU rRNA gene, the strains were assigned to two distinct species, Trichosporiella flavificans and representatives of a new yeast species. Phylogenetic analyses revealed that Candida ghanaensis CBS 8798T showed a strong relationship with the aforementioned two species. The more fascinating issue is that Candida and Trichosporiella genera have been placed in different subphyla, Saccharomycotina and Pezizomycotina, respectively. The close relationship between Trichosporiella flavificans, Candida ghanaensis and the undescribed species was unexpected and needed to be clarified. As for morphological and physiological characteristics, the three yeast species shared a hairy colony appearance and an ability to assimilate 18 carbon sources. Based on phylogenetic analyses carried out in the present study, Crinitomyces gen. nov. was proposed to accommodate the new yeast species, Crinitomyces reliqui sp. nov. (Holotype: TBRC 15054, Isotypes: DMKU-FW23-23 and PYCC 9001). In addition, the two species Trichosporiella flavificans and Candida ghanaensis were reassigned to the genus Crinitomyces as, Crinitomyces flavificans (Type: CBS 760.79) comb. nov. and Crinitomyces ghanaensis (Type: CBS 8798) comb. nov., respectively.
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