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Phylogenetic trees of Debaryomyces hansenii complex species. (a) Alignment of the 5′ part of the IGS comprising NTS1, RDN5-1, NTS3 and RDN5-2 sequences was performed with mafft and cleaned with gblocks. The tree was built with a Neighbor-Joining algorithm (clustalx) from the nucleotide alignment of the resulting 724 informative residues. Robustness of the tree was estimated with bootstrap values on 1000 replicates, indicated next to the nodes. Species names admitted in this study figured on the right. (b) Sequences of ACT1 (830 residues), GPD (1063 residues) and COX2 (566 residues) genes were aligned independently with mafft and then concatenated. The tree resulting from the alignment of the 2459 residues was built with the Neighbor-Joining algorithm (clustalx) and its robustness was estimated with bootstrap values on 1000 replicates next to the nodes. Type strain of Debaryomyces coudertii was used as the out-group in both trees. Type strains are indicated in bold and by ‘T’.
Source publication
The intergenic spacer rDNA amplification and AluI fingerprinting (IGSAF) method detected four distinct groups among 170 Debaryomyces hansenii strains: D. hansenii var. hansenii; Candida famata var. famata; D. hansenii var. fabryi and C. famata var. flareri. IGS sequence comparison of representative strains showed that D. hansenii var. hansenii and...
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... order to validate the phylogenetic relationships deduced from ribosomal sequences, the sequences of two nuclear and one mitochondrial protein-coding genes were com- pared: ACT1 and COX2 as universal phylogenetic markers (Kurtzman & Robnett, 2003;Tsui et al., 2008) and GPD as Debaryomyces-specific marker. Figure 5b shows that the phylogenetic tree established from 2459 bp of concatenated ACT1, GPD1 and COX2 sequences is congruent with the upIGS tree ( Fig. 5a): it clusters all strains with a Deha or a Cafa pattern into one well-supported clade (bootstrap value = 1000). Within this clade, we noticed that, like in the upIGS tree, all strains with a Cafa pattern grouped together, suggesting that they form a lineage representing a particular population. ...
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... and one mitochondrial protein-coding genes were com- pared: ACT1 and COX2 as universal phylogenetic markers (Kurtzman & Robnett, 2003;Tsui et al., 2008) and GPD as Debaryomyces-specific marker. Figure 5b shows that the phylogenetic tree established from 2459 bp of concatenated ACT1, GPD1 and COX2 sequences is congruent with the upIGS tree ( Fig. 5a): it clusters all strains with a Deha or a Cafa pattern into one well-supported clade (bootstrap value = 1000). Within this clade, we noticed that, like in the upIGS tree, all strains with a Cafa pattern grouped together, suggesting that they form a lineage representing a particular population. Interestingly, strain CBS 1961, which ...
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... order to validate the phylogenetic relationships deduced from ribosomal sequences, the sequences of two nuclear and one mitochondrial protein-coding genes were com- pared: ACT1 and COX2 as universal phylogenetic markers (Kurtzman & Robnett, 2003;Tsui et al., 2008) and GPD as Debaryomyces-specific marker. Figure 5b shows that the phylogenetic tree established from 2459 bp of concatenated ACT1, GPD1 and COX2 sequences is congruent with the upIGS tree ( Fig. 5a): it clusters all strains with a Deha or a Cafa pattern into one well-supported clade (bootstrap value = 1000). Within this clade, we noticed that, like in the upIGS tree, all strains with a Cafa pattern grouped together, suggesting that they form a lineage representing a particular population. Interestingly, strain CBS 1961, which exhibits a polymorphic IGS pattern [Deha (P2) ] and a divergent upIGS sequence, clusters with the C. famata lineage in the protein tree. Further investigations on this strain and also on strain CBS 1960, which exhibits the same Deha (P2) pattern (Table 1), should be undertaken to clarify their taxonomic position and eventually their hybrid nature. Another observation was that other D. hansenii strains exhibiting polymorphic IGS patterns, CBS 766 and CLIB 660, diverged significantly from the type strain CBS 767 T with a high confidence value (bootstrap = 1000). However, we still consider them as belonging to the D. hansenii species because the nucleotide conservation in ACT1 for example is higher than between the two closest species of the Saccharomyces sensu stricto, i.e. 97% between S. cerevisiae and S. paradoxus (Supporting Information, Table S1). In addition, the branching of D. prosopidis is unclear as it is different in both trees and poorly supported. Another physiological trait, riboflavin production has been attributed to C. famata in studies using strain VKM Y-9 from it several genes in the riboflavin biosynthetic pathway have been cloned and analysed (Voronovsky et al., 2004). As strain VKM Y-9 was reidentified as C. flareri in this study, riboflavin production on minimal medium by all D. subglobosus/C. flareri strains identified here was checked and compared with other species in the D. hansenii complex, using strain VKM Y-9 as a positive reference. Table S2 shows that among strains tested, only those characterized by a Defy or Cafi pattern produced riboflavin on minimal liquid medium at 28 1C, detected after 24 h either visually or by spectrophotometer analysis. Strain CBS 4373 (D. fabryi) produced riboflavin at a low level considered here as the basal level, comparatively the type strain CBS 789 T produced 1.5 times more of this substance. The D. subglobosus strains produced the highest quantity of riboflavin on minimal medium. Strain VKM Y-9 produced roughly 3.5 times the basal level but the highest producers were the type strain CBS 792 T and strain CBS 2659 with amounts reaching six times the basal level. This test showed that D. subglobosus strains tend to produce riboflavin more efficiently than D. fabryi strains. Debaryomyces (830 residues), GPD (1063 residues) and COX2 (566 residues) genes were aligned independently with MAFFT and then concatenated. The tree resulting from the alignment of the 2459 residues was built with the Neighbor-Joining algorithm (CLUSTALX) and its robustness was estimated with bootstrap values on 1000 replicates next to the nodes. Type strain of Debaryomyces coudertii was used as the out-group in both trees. Type strains are indicated in bold and by 'T'. prosopidis, which is closely related to D. fabryi and D. subglobosus bearing RIB gene homologues, also produces riboflavin, but less efficiently than D. fabryi. On the other hand, none of the 37 D. hansenii/C. famata strains tested produced significant quantity of riboflavin under the same conditions (Table S2), even though RIB biosynthetic genes are present in the CBS 767 T genome ( Dujon et al., 2004). Riboflavin production tested under these conditions seems thus to be a more reliable test than growth temperature to differentiate D. hansenii from D. fabryi and D. ...
Context 4
... order to validate the phylogenetic relationships deduced from ribosomal sequences, the sequences of two nuclear and one mitochondrial protein-coding genes were com- pared: ACT1 and COX2 as universal phylogenetic markers (Kurtzman & Robnett, 2003;Tsui et al., 2008) and GPD as Debaryomyces-specific marker. Figure 5b shows that the phylogenetic tree established from 2459 bp of concatenated ACT1, GPD1 and COX2 sequences is congruent with the upIGS tree ( Fig. 5a): it clusters all strains with a Deha or a Cafa pattern into one well-supported clade (bootstrap value = 1000). Within this clade, we noticed that, like in the upIGS tree, all strains with a Cafa pattern grouped together, suggesting that they form a lineage representing a particular population. Interestingly, strain CBS 1961, which exhibits a polymorphic IGS pattern [Deha (P2) ] and a divergent upIGS sequence, clusters with the C. famata lineage in the protein tree. Further investigations on this strain and also on strain CBS 1960, which exhibits the same Deha (P2) pattern (Table 1), should be undertaken to clarify their taxonomic position and eventually their hybrid nature. Another observation was that other D. hansenii strains exhibiting polymorphic IGS patterns, CBS 766 and CLIB 660, diverged significantly from the type strain CBS 767 T with a high confidence value (bootstrap = 1000). However, we still consider them as belonging to the D. hansenii species because the nucleotide conservation in ACT1 for example is higher than between the two closest species of the Saccharomyces sensu stricto, i.e. 97% between S. cerevisiae and S. paradoxus (Supporting Information, Table S1). In addition, the branching of D. prosopidis is unclear as it is different in both trees and poorly supported. Another physiological trait, riboflavin production has been attributed to C. famata in studies using strain VKM Y-9 from it several genes in the riboflavin biosynthetic pathway have been cloned and analysed (Voronovsky et al., 2004). As strain VKM Y-9 was reidentified as C. flareri in this study, riboflavin production on minimal medium by all D. subglobosus/C. flareri strains identified here was checked and compared with other species in the D. hansenii complex, using strain VKM Y-9 as a positive reference. Table S2 shows that among strains tested, only those characterized by a Defy or Cafi pattern produced riboflavin on minimal liquid medium at 28 1C, detected after 24 h either visually or by spectrophotometer analysis. Strain CBS 4373 (D. fabryi) produced riboflavin at a low level considered here as the basal level, comparatively the type strain CBS 789 T produced 1.5 times more of this substance. The D. subglobosus strains produced the highest quantity of riboflavin on minimal medium. Strain VKM Y-9 produced roughly 3.5 times the basal level but the highest producers were the type strain CBS 792 T and strain CBS 2659 with amounts reaching six times the basal level. This test showed that D. subglobosus strains tend to produce riboflavin more efficiently than D. fabryi strains. Debaryomyces (830 residues), GPD (1063 residues) and COX2 (566 residues) genes were aligned independently with MAFFT and then concatenated. The tree resulting from the alignment of the 2459 residues was built with the Neighbor-Joining algorithm (CLUSTALX) and its robustness was estimated with bootstrap values on 1000 replicates next to the nodes. Type strain of Debaryomyces coudertii was used as the out-group in both trees. Type strains are indicated in bold and by 'T'. prosopidis, which is closely related to D. fabryi and D. subglobosus bearing RIB gene homologues, also produces riboflavin, but less efficiently than D. fabryi. On the other hand, none of the 37 D. hansenii/C. famata strains tested produced significant quantity of riboflavin under the same conditions (Table S2), even though RIB biosynthetic genes are present in the CBS 767 T genome ( Dujon et al., 2004). Riboflavin production tested under these conditions seems thus to be a more reliable test than growth temperature to differentiate D. hansenii from D. fabryi and D. ...
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... Genotyping of these strains was performed by intergenic spacer rDNA amplification and AluI Fingerprinting (IGSAF). The IGSAF technique has been successfully used to differentiate previously misidentified species in different taxa [73,74]. ...
Background:
In the context of sustainable development, yeast are one class of microorganisms foreseen for the production of oil from diverse renewable feedstocks, in particular those that do not compete with the food supply. However, their use in bulk production, such as for the production of biodiesel, is still not cost effective, partly due to the possible poor use of desired substrates or poor robustness in the practical bioconversion process. We investigated the natural capacity of Blastobotrys adeninivorans, a yeast already used in biotechnology, to store lipids under different conditions.
Results:
The genotyping of seven strains showed the species to actually be composed of two different groups, one that (including the well-known strain LS3) could be reassigned to Blastobotrys raffinosifermentans. We showed that, under nitrogen limitation, strains of both species can synthesize lipids to over 20% of their dry-cell weight during shake-flask cultivation in glucose or xylose medium for 96 h. In addition, organic acids were excreted into the medium. LS3, our best lipid-producing strain, could also accumulate lipids from exogenous oleic acid, up to 38.1 ± 1.6% of its dry-cell weight, and synthesize lipids from various sugar substrates, up to 36.6 ± 0.5% when growing in cellobiose. Both species, represented by LS3 and CBS 8244T, could grow with little filamentation in the lipogenic medium from 28 to 45 °C and reached lipid titers ranging from 1.76 ± 0.28 to 3.08 ± 0.49 g/L in flasks. Under these conditions, the maximum bioconversion yield (YFA/S = 0.093 ± 0.017) was obtained with LS3 at 37 °C. The presence of genes for predicted subunits of an ATP citrate lyase in the genome of LS3 reinforces its oleaginous character.
Conclusions:
Blastobotrys adeninivorans and B. raffinosifermentans, which are known to be xerotolerant and genetically-tractable, are promising biotechnological yeasts of the Saccharomycotina that could be further developed through genetic engineering for the production of microbial oil. To our knowledge, this is the first report of efficient lipid storage in yeast when cultivated at a temperature above 40 °C. This paves the way to help reducing costs through consolidated bioprocessing.
... There is another exception, strain CLIB 1604 (Table 1), which belongs to the genus Debaryomyces. In this genus, divergence at the level of the rDNA gene may be highly reduced, for example in the Debaryomyces hansenii/Debaryomyces fabryi species complex [46,47] therefore our threshold does not apply. Indeed, the partial sequence for the actin coding gene was obtained for CLIB 1604 and it differed by six bp plus one indel (out of 818 bp) from that of the D. hansenii type strain CBS 767 T . ...
The extent of the diversity of yeasts in tropical rain forest and different environments from French Guiana was investigated. A total of 365 samples were collected from various substrates, such as plants, fruits and insects, at 13 locations, yielding 276 pure yeast isolates. Sequence analysis of the D1/D2 domains of the large subunit rRNA gene indicated that 210 isolates out of 276 belonged to 82 described species (67 Saccharomycotina, 14 Basidiomycota and 1 Pezizomycotina). In addition to these, a total of 54 Saccharomycotina isolates could not be assigned to a known species. These belonged to 14 genera and should be studied further from a taxonomic point of view. In addition, among the 43 Basidiomycotina isolates found, 12 could not be assigned to a known species. This report shows an unexpected biodiversity and indicates that oversea territories, such as French Guiana, constitute a largely unexplored reservoir for yeast diversity. Two Saccharomycotina strains, CLIB 1706 and CLIB 1725, isolated from an insect and from a fern respectively, were characterized further and were shown to belong to the Suhomyces clade on the basis of the rDNA sequence comparison. CLIB 1706TrDNA sequences showed nine substitutions and three indels out of 556 bp (D1/D2 domains) and 32 substitutions and 12 indels out of 380 bp [internal transcribed spacer (ITS)] with that of the most closely related species Suhomyces guaymorum CBS 9823T. CLIB 1725T rDNA sequences presented 18 substitutions and one indel out of 549 bp (D1/D2 domains) and 48 substitutions and 11 indels out of 398 bp (ITS) with that of its closest relative Suhomyces vadensis CBS 9454T. Two novel species of the genus Suhomyces were described to accommodate these two strains: Suhomyces coccinellae f.a. sp. nov. (CLIB 1706T=CBS 14298T) and Suhomyces faveliae f.a. sp. nov. (CLIB 1725T=CBS 14299T).
... Growth levels were evaluated by the sizes of colonies on a P(3HB) plate at 6 different temperatures (4,20,25,30,37, and 50 C) for 5 days, and P(3HB) degradation abilities were evaluated by those of clear zones formed on a P(3HB) plate at 6 different temperatures (4,20,25,30,37, and 50 C) for 5 days. ...
... Growth levels were evaluated by the sizes of colonies on a P(3HB) plate at 6 different temperatures (4,20,25,30,37, and 50 C) for 5 days, and P(3HB) degradation abilities were evaluated by those of clear zones formed on a P(3HB) plate at 6 different temperatures (4,20,25,30,37, and 50 C) for 5 days. ...
... Debaryomyces udenii was the main fungal species in cheese 1 (99.5%) and cheese 3 (100%). This strain was isolated from soil samples in previous studies [25,26]. To our knowledge, this is the first time this fungus was detected in cheese. ...
Since the use of biodegradable polymers for food packaging is becoming popular, it is important to investigate the biodegradable-polymer-hydrolyzing potential of microorganisms in fermented foods. Here, we focused on 4 Japanese washed-rind cheeses. Metagenomic analyses revealed that microbiota in the 4 Japanese washed-rind cheeses was composed of bacteria classified into 515 operational taxonomic units (OTUs) and fungi classified into 74 OTUs. Remarkably, a considerable number of marine bacteria were identified in 3 of 4 cheeses. Further, we isolated a poly(3-hydroxybutyrate) (P(3HB))-degrading bacterium, designated as strain MC1, from one of the cheeses—Muchuri. The strain was a gram-negative, rod-shaped bacterium. It grew well and formed a large clear zone on P(3HB)-containing medium at a temperature range of 30–37 °C, while it did not degrade P(3HB) at 4 °C. The phenotypic properties and phylogenetic inference indicated that strain MC1 is related to Alcanivorax dieselolei B-5T, which is a marine inhabitant. Our study demonstrated that MC1 degrades P(3HB) and that components in cheese promote the degradation of P(3HB) while nutrient-rich conditions suppress it. This suggests that packaging material made of P(3HB) for cheeses could be used under low temperatures and nutrient-rich conditions.
... 15 Candida famata (Debaryomyces hansenii) is also part of a species complex compromising until now the following species: C. famata (D. hansenii), D. fabryi, C. flareri (D. subglobosus), D. macquariensis, D. prosopidis, D. maramus, D. nepalensis, D. vietnamensis, D. courdetii, D. vindobonensis, and D. tyrocola. [16][17][18][19] Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) is replacing conventional phenotypic identification methods in clinical laboratories, and it has proven to be a reliable system for identification of common and rare emerging yeast pathogens. 12,20,21 In light of previous studies that demonstrated that conventional phenotypic identification of C. guilliermondii and C. famata is not reliable and in view of the new taxonomic changes, the aim of the present work was to reidentify strains previously identified as C. guilliermondii and C. famata by conventional phenotypic methods conserved in a culture collection using ribosomal DNA sequencing, ACT1 gene sequencing, and MALDI-TOF MS. ...
The aim of this work was to reidentify strains previously identified as Candida guilliermondii and Candida famata by conventional phenotypic methods conserved in a culture collection from Argentina using ribosomal DNA sequencing, ACT1 gene sequencing, and matrix-assisted laser desorption ionization - time of flight mass spectrometry (MALDI-TOF MS). In addition, we performed antifungal susceptibility tests of eight antifungal drugs commonly used in clinical treatment. We identified 68 isolates belonging to the Candida guilliermondii species complex (59 C. guilliermondii, 8 C. fermentati, and 1 Candida carpophila), 16 isolates belonging to the Candida famata species complex (8 C. famata, 6 Debaryomyces nepalensis, 1 Debaryomyces fabryi, and 1 Debaryomyces tyrocola). Although sequencing of ITS region was able to identify C. guilliermondii and D. nepalensis isolates, sequencing of ACT1 gene seems to be the most appropriate technique for differentiation between C. fermentati and C. carpophila and between members of the C. famata species complex others than D. nepalensis. MALDI-TOF MS has a good potential for the identification of these yeasts, particularly in clinical laboratories since is a rapid and easy to perform technique. Here, we report the first isolation of D. tyrocola from a human patient and the first isolation of D. nepalensis from lungs and blood of human patients. Finally, correct identification and determination of antifungal susceptibility of those closely related species could be a useful tool for clinicians to choose the most effective antifungal treatment.
... D. hansenii strains represented the most diverse cluster, but this cluster remained separate from their close taxonomic relatives D. subglobosus, D. fabryi (data not shown). The position of D. hansenii in the MALDI-TOF MS dendrogram fits well with the close phylogenetic relationship between D. hansenii, D. subglobosus and D. fabryi (Jacques et al., 2009;Groenewald et al., 2008;Nguyen et al., 2009). In the genus Hanseniaspora all 13 species could be separated, except one strain of H. lachancei (CBS 9197) that had a position between H. opuntiae strains and other H. lachancei strains. ...
Since food spoilage by yeasts causes high economic losses, fast and accurate identifications of yeasts associated with food and food-related products are important for the food industry. In this study the efficiency of the matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify food related yeasts was evaluated. A CBS in-house MALDI-TOF MS database was created and later challenged with a blinded test set of 146 yeast strains obtained from food and food related products. Ninety eight percent of the strains were correctly identified with log score values>1.7. One strain, Mrakia frigida, gained a correct identification with a score value<1.7. Two strains could not be identified at first as they represented a mix of two different species. These mixes were Rhodotorula babjevae with Meyerozyma caribbica and Clavispora lusitaniae with Debaryomyces hansenii. After separation, all four species could be correctly identified with scores>1.7. Ambiguous identifications were observed due to two incorrect reference mass spectra's found in the commercial database BDAL v.4.0, namely Candida sake DSM 70763 which was re-identified as Candida oleophila, and Candida inconspicua DSM 70631 which was re-identified as Pichia membranifaciens. MALDI-TOF MS can distinguish between most of the species, but for some species complexes, such as the Kazachstania telluris and Mrakia frigida complexes, MALDI-TOF MS showed limited resolution and identification of sibling species was sometimes problematic. Despite this, we showed that the MALDI-TOF MS is applicable for routine identification and validation of foodborne yeasts, but a further update of the commercial reference databases is needed.
... famata, and C. famata has been renamed D. hansenii [14,15]. Thus, in work published prior to 2011, C. famata and D. hansenii are cautiously regarded as the same organism [16]. Debaryomyces hansenii was also once thought to exist in two varieties: D. hansenii var. ...
... Dmytruk et al. used the electroporation method for random insertion mutagenesis via an integrative plasmid having the S. cerevisiae-derived LEU2 gene for selection, obtaining transformation efficiencies of 40-200 transformants/µg DNA [56]. It should be noted that the organism utilized in the research conducted by Vornovosky et al. and Dmytruk et al. has been classified as D. fabryi rather than D. hansenii [16]. Electroporation methods for D. hansenii have utilized hygomycin B (hyg) resistance and uracil prototrophy [57], as well as gene disruption with selection by histidine auxotrophy complementation [58]. ...
There is growing interest in using oleaginous yeast for the production of a variety of fatty acids and fatty acid-derived oleochemicals. This is motivated by natural propensity for high flux through lipid biosynthesis that has naturally evolved, making them a logical starting point for additional genetic engineering to improve titers and productivities. Much of the academic and industrial focus has centered on yeast that have significant genetic engineering tool capabilities, such as Yarrowia lipolytica, and those that have naturally high lipid accumulation, such as Rhodosporidium toruloides and Lipomyces starkeyi; however, there are oleaginous yeast with phenotypes better aligned with typically inhibitory process conditions, such as high salt concentrations and lignocellulosic derived inhibitors. This review addresses the foundational work in characterizing two emerging oleaginous yeast of interest: Debaryomyces hansenii and Trichosporon oleaginosus. We focus on the physiological and metabolic properties of these yeast that make each attractive for bioprocessing of lignocellulose to fuels and chemicals, discuss their respective genetic engineering tools and highlight the critical barriers facing the broader implementation of these oleaginous yeast.
... Segura, (2010) del mismo modo reporta que para la especies de levadura Kuyvemyces lactis y Kluveromyces marcianus los patrones de banda son muy similares lo que resultaría difícil la correcta identificación a través de la técnica PCR-RFLP y que no solo a nivel molecular es complicado sino también la correcta identificación morfofisiológica, al igual que sucede con el género Trichosporon (Middelhoven et al., 2001). Por lo cual y considerando estos antecedentes, para el caso de las levaduras T. dulcitum, T. lignícola y T. porosum sería necesario, probar con otras endonucleasas que generen patrones de polimorfismo diferentes para cada especie, o como ya se ha mencionado la utilización de una región que presente mayor hipevariabilidad como las regiones IGS que han sido utilizadas para identificar varias levaduras Basidiomycetes (Nguyen et al., 2009). ...
Las levaduras juegan un importante rol en la naturaleza siendo el mayor reservorio de ellas el suelo. Mediante el método de las diluciones seriadas y posterior siembra en agar Sabouraud se aislaron en cultivo puro 77 cepas de levaduras desde un mismo suelo trumao del sur de Chile, usado como pradera permanente (30 cepas), pradera en rotación (30 cepas) y como control bosque nativo (17 cepas), estas cepas se identificaron molecularmente por PCR-RFLP en conjunto con secuenciación del rDNA de ITS-5.8S, además se realizo una caracterización fisiológica (asimilación fuente de carbono, de nitrógeno y fermentación de azucares) a cada cepa. Mediante las técnicas moleculares las 77 cepas se reunieron en 10 grupos, de estos solamente tres grupos se pudieron identificar a nivel de especie y uno hasta género: Devariomyces hansenii. Pichia fermentan. Kazachstania exigua., Candida sp.
... Partial LSU rDNA and ITS sequences were submitted to GenBank. Since only LSU rDNA sequences of identified Clinoconidium species were available, LSU rDNA sequences of Cryptobasidiaceae and Ustilago maydis as outgroup were retrieved from GenBank from BLAST searches and publications (Begerow et al. 2002;Boekhout et al. 2003;Yasuda et al. 2005;Maier et al. 2006;Nguyen et al. 2009;Kottke et al. 2010;Piepenbring et al. 2010). An alignment was made with MUSCLE implemented in MEGA6 without manual editing except for trimming the ends in order to obtain an even block with a length of 556 positions (TreeBASE S19276). ...
The obscure species Exobasidium sawadae and the enigmatic hyphomycetous genus Elaeodema transform fruits of Cinnamomum species to galls. Fresh collections from Guangxi in China and Taiwan island were studied with microscopy and analysis of partial large subunit (LSU) ribosomal RNA gene sequences. Study of young stages and of isotype material of El. cinnamomi revealed the presence of basidia. Haustoria are demonstrated in both species for the first time. Sterile elements were found between basidia in galls of El. cinnamomi, whereas sterile elements were absent in Ex. sawadae. Based on the morphology of spore germination and the anamorphic yeast stage in culture, and a phylogenetic species concept, these two species were combined into Clinoconidium. Elaeodema is considered a synonym of Clinoconidium. The data indicate high specificity of Clinoconidium species to their lauraceous hosts.
... These results indicate that the French and Brazilian strains may belong to an as yet undescribed species. The use of sequences from rRNA genes for species delineation may be misleading because they may provide poor discrimination, as already observed for the genus Debaryomyces for example (Groenewald et al., 2008;Jacques et al., 2009;Nguyen et al., 2009). This observation and the need for a more robust phylogeny between these species in this part of the Kazachstania clade prompted us to analyse other sequences, such as the protein coding gene sequences RPB1, RPB2 and EF-1a. ...
Five ascosporogenous yeast strains related to the genus Kazachstania were isolated. Two strains (CLIB 1764T and CLIB 1780) were isolated from French sourdoughs; three others (UFMG-CM-Y273T, UFMG-CM-Y451 and UFMG-CM-Y452) were from rotting wood in Brazil. The sequences of the French and Brazilian strains differed by one and three substitutions, respectively in the D1/D2 LSU rRNA gene and the ITS. The D1/D2 LSU rRNA sequence of these strains differed by 0.5% and 0.7% from Kazachstania exigua, but their ITS sequences diverged by 8.1 and 8.3 %, respectively, from that of the closest described species Kazachstania barnetti. Analysis of protein coding sequences of RPB1, RPB2 and EF- distinguished the French from the Brazilian strains, with respectively 3.3%, 6% and 11.7% substitutions. Two novel species are described to accommodate these newly isolated strains: Kazachastania saulgeensis sp. nov. (type strain CLIB 1764T = CBS 14374T) and Kazachstania serrabonitensis sp. nov. (type strain UFMG-CM-Y273T = CLIB 1783T = CBS 14236T). Further analysis of culture collections revealed a strain previously assigned to the Kazachstania exigua species, but having 3.8% difference (22 substitutions and 2 indels) in its ITS with respect to K. exigua. Hence, we describe a new taxon, Kazachatania australis sp. nov. (type strain CLIB 162T = CBS 2141T), to accommodate this strain. Finally, Candida humilis and Candida pseudohumilis are reassigned to the genus Kazachstania as new combinations. On the basis of sequence analysis, we also propose that Candida milleri and Kazachstania humilis comb. nov. are conspecific.
... metal-resistant ascomycete yeast widely distributed in nature (1,2). This organism has been taxonomically differentiated into D. hansenii and D. fabryi (3,4). J6 is a flavinogenic Debaryomyces strain that grows between 15 and 37°C and tolerates heavy metals such as cobalt(II) (5). ...
V. contributed equally to this article. Debaryomyces hansenii J6 is a heavy-metal-tolerant, flavinogenic yeast isolated from a Swedish estuary. We present here the 11.63-Mb genome of this organism containing 5,717 open reading frames. Comparison with available Debaryomyces genomes demonstrated that J6 is closer to D. hansenii MTCC234 than D. fabry CBS789 and D. hansenii CBS767. Citation Berrocal CA, Rivera-Vicens RE, Nadathur GS. 2016. Draft genome sequence of the heavy-metal-tolerant marine yeast Debaryomyces hansenii J6. Genome Announc 4(5): e00983-16.
