RESUMEN
Recent studies have suggested that species of the Kazachstania genus may be interesting models of yeast domestication. Among these, Kazachstania barnettii has been isolated from various microbially transformed foodstuffs such as sourdough bread and kefir. In the present work, we sequence, assemble, and annotate the complete genomes of two K. barnettii strains: CLIB 433, being one of the two reference strains for K. barnettii that was isolated as a spoilage organism in soft drink, and CLIB 1767, recently isolated from artisan bread-making sourdough. Both assemblies are of high quality with N50 statistics greater than 1.3 Mb and BUSCO score greater than 99%. An extensive comparison of the two obtained genomes revealed very few differences between the two K. barnettii strains, considering both genome structure and gene content. The proposed genome assemblies will constitute valuable references for future comparative genomic, population genomic, or transcriptomic studies of the K. barnettii species.
Asunto(s)
Saccharomycetales , Pan , Fermentación , Saccharomycetales/genética , LevadurasRESUMEN
Geotrichum candidum is an environmental yeast, also found as part of the cheese surface microbiota, where it is important in the ripening of many traditional cheeses, such as Camembert. We have previously developed a Multi Locus Sequence Typing (MLST) scheme, which differentiated five clades, of which one contained only environmental isolates, two were composed almost entirely of dairy isolates, and two others contained a mixture of dairy, environmental, and miscellaneous food isolates. In order to provide a simple method to uniquely type G. candidum strains, and in addition to permit investigation of the population structure at a fine level, we describe here a molecular analysis using a set of twelve highly discriminating microsatellite-like markers. The present study consolidates the previously suggested division between dairy and environmental strains, and in addition distinguishes a specifically European group of environmental strains. This analysis permitted the discrimination of 72 genotypes from the collection of 80 isolates, while retaining the underlying meaningful phylogenetic relation between groups of strains.
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Yeasts can have additional genetic information in the form of cytoplasmic linear dsDNA molecules called virus-like elements (VLEs). Some of them encode killer toxins. The aim of this work was to investigate the prevalence of such elements in D. hansenii killer yeast deposited in culture collections as well as in strains freshly isolated from blue cheeses. Possible benefits to the host from harboring such VLEs were analyzed. VLEs occurred frequently among fresh D. hansenii isolates (15/60 strains), as opposed to strains obtained from culture collections (0/75 strains). Eight new different systems were identified: four composed of two elements and four of three elements. Full sequences of three new VLE systems obtained by NGS revealed extremely high conservation among the largest molecules in these systems except for one ORF, probably encoding a protein resembling immunity determinant to killer toxins of VLE origin in other yeast species. ORFs that could be potentially involved in killer activity due to similarity to genes encoding proteins with domains of chitin-binding/digesting and deoxyribonuclease NucA/NucB activity, could be distinguished in smaller molecules. However, the discovered VLEs were not involved in the biocontrol of Yarrowia lipolytica and Penicillium roqueforti present in blue cheeses.
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Queso/virología , Citoplasma/virología , Debaryomyces/virología , Micotoxinas/análisis , RetroelementosRESUMEN
The unambiguous application of fungal names is important to communicate scientific findings. Names are critical for (clinical) diagnostics, legal compliance, and regulatory controls, such as biosafety, food security, quarantine regulations, and industrial applications. Consequently, the stability of the taxonomic system and the traceability of nomenclatural changes is crucial for a broad range of users and taxonomists. The unambiguous application of names is assured by the preservation of nomenclatural history and the physical organisms representing a name. Fungi are extremely diverse in terms of ecology, lifestyle, and methods of study. Predominantly unicellular fungi known as yeasts are usually investigated as living cultures. Methods to characterize yeasts include physiological (growth) tests and experiments to induce a sexual morph; both methods require viable cultures. Thus, the preservation and availability of viable reference cultures are important, and cultures representing reference material are cited in species descriptions. Historical surveys revealed drawbacks and inconsistencies between past practices and modern requirements as stated in the International Code of Nomenclature for Algae, Fungi, and Plants (ICNafp). Improper typification of yeasts is a common problem, resulting in a large number invalid yeast species names. With this opinion letter, we address the problem that culturable microorganisms, notably some fungi and algae, require specific provisions under the ICNafp. We use yeasts as a prominent example of fungi known from cultures. But viable type material is important not only for yeasts, but also for other cultivable Fungi that are characterized by particular morphological structures (a specific type of spores), growth properties, and secondary metabolites. We summarize potential proposals which, in our opinion, will improve the stability of fungal names, in particular by protecting those names for which the reference material can be traced back to the original isolate.
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Natural products are a reliable source of bioactive molecules and represent an industrial and pharmaceutical stake. Indeed, the model yeast species Saccharomyces cerevisiae is a well-known eukaryotic organism largely used as a biotechnological tool, but still a topical subject of study. In this work, the exploration of Saccharomyces cerevisiae is taken further through an untargeted metabolomics workflow. The aim is to enrich databases and bring new information about the standard S. cerevisiae strain in a given medium. Analytical methods and bioinformatics tools were combined in a high-throughput methodology useable to dereplicate many types of biological extracts and cartography secondary metabolites. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analyses were carried out and spectral data were pre-processed to build molecular networks. Annotations were attributed to compounds through comparison with databases and manual investigation of networks. Ultra-high-resolution Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS) brought additional information thanks to a higher dynamic range and enhanced UHPLC-MS/MS results by unveiling ambiguities and bringing accurate molecular formulae. Therefore, accurate and reliable annotated features resulted from the UHPLC-MS/MS data while FTICR-MS provided an overall cartography of metabolites thanks to van Krevelen diagrams. Various small molecules such as amino acids derivatives and indole alkaloids have been determined for the first time in this yeast. The complementarity of FTICR-MS and UHPLC-MS/MS for secondary metabolite annotation brought this new mapping of S. cerevisiae.
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Productos Biológicos , Saccharomyces cerevisiae , Cromatografía Líquida de Alta Presión , Metabolómica , Espectrometría de Masas en TándemRESUMEN
Two strains (DMKU-GTCP10-8 and CLIB 1740) representing a novel anamorphic yeast species were isolated from a grease sample collected from a grease trap in Thailand and from an unidentified fungus collected in French Guiana, respectively. On the basis of phylogenetic analysis based on the combined D1/D2 domain of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, Lachancea fermentati CBS 707T was the closely related species with 12.8â% sequence divergence (70 nucleotide substitutions and three gaps in 571 nucleotides) and 28.1â% sequence divergence (93 nucleotide substitutions and 90 gaps in 651 nucleotides) in the D1/D2 domain of the LSU rRNA gene and the ITS region, respectively. Phylogenetic analysis based on the concatenated sequences of the five genes including the small subunit rRNA gene, the D1/D2 domain of the LSU rRNA gene, the ITS region, translation elongation factor-1 alpha (TEF1) and RNA polymerase II subunit 2 (RPB2) genes confirmed that the two strains (DMKU-GTCP10-8 and CLIB 1740) were well-separated from other described yeast genera in Saccharomycetaceae. Hence, Savitreea pentosicarens gen. nov., sp. nov. is proposed to accommodate these two strains as members of the family Saccharomycetaceae. The holotype is S. pentosicarens DMKU-GTCP10-8T (ex-type strain TBRC 12159=PYCC 8490; MycoBank number 835044).
Asunto(s)
Filogenia , Saccharomycetales/clasificación , Composición de Base , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Guyana Francesa , Genes de ARNr , Técnicas de Tipificación Micológica , Factor 1 de Elongación Peptídica/genética , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia de ADN , TailandiaRESUMEN
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).
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Biodiversidad , Filogenia , Bosque Lluvioso , Saccharomycetales/clasificación , Animales , Composición de Base , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Helechos/microbiología , Guyana Francesa , Mutación INDEL , Insectos/microbiología , Técnicas de Tipificación Micológica , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia de ADNRESUMEN
In order to assess the genetic diversity and population structure of indigenous S. cerevisiae from Côte d'Ivoire, a total of 170 strains were isolated from four traditional alcoholic beverages through nine regions. Microsatellite analysis performed at 12 loci revealed that strains of palm oil and raffia wine were genetically related, unlike those of tchapalo and ron wine which formed two s from palm oil wine and raffia wine were clearly inbred. In comparison with the European, North American, Asian and others West African populations, Ivorian population was well defined, although most of these strains were admixed. Among these strains, only isolates from raffia wine appeared to have alleles in common to all populations.
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Bebidas Alcohólicas/microbiología , Variación Genética , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/genética , Arecaceae , Côte d'Ivoire , Repeticiones de Microsatélite/genética , Vino/microbiologíaRESUMEN
Twelve strains of a novel yeast species were isolated from rotting wood, mushrooms and fruit samples in Brazil and French Guiana. Analysis of the sequences of the internal transcribed spacer region and the D1/D2 domains of the large subunit rRNA gene showed that the novel species belongs to the Kurtzmaniella clade. The novel species differed from its closest relative, Candida natalensis, by 12 substitutions in the D1/D2 sequences. The novel species could be distinguished from C. natalensis by its inability to assimilate cellobiose and salicin, and growth at 50â% (w/w) glucose. The name Kurtzmaniella hittingeri f.a., sp. nov. is proposed for the novel species. The type strain of K. hittingeri sp. nov. is CBS 13469T (=UFMG CM-Y272T). The MycoBank number is 827183. We also propose the transfer of Candida fragi, Candida quercitrusa and Candida natalensis to the genus Kurtzmaniella as new combinations.
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Candida/clasificación , Frutas/microbiología , Filogenia , Madera/microbiología , Alcoholes Bencílicos , Brasil , Candida/aislamiento & purificación , Celobiosa , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Guyana Francesa , Glucósidos , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADNRESUMEN
Microbial communities are essential for the maintenance and functioning of ecosystems, including fermented food ecosystems. The analysis of food microbial communities is mainly focused on lactic acid bacteria (LAB), while yeast diversity is less understood. Here, we describe the fungal diversity of a typical food fermented product, sourdough bread. The species diversity of 14 sourdoughs collected from bakeries located all over France was analyzed. Bakeries were chosen to represent diverse bakery practices and included bakers and farmer-bakers. Both non-culture-based (pyrosequencing of Internal Transcribed Spacer 1 amplicons) and culture-based methods were used. While both identification methods were in agreement regarding the dominant yeast species of each sourdough, the ITS1 metabarcoding analysis identified an increased number of fungal species in sourdough communities. Two third of the identified sequences obtained from sourdoughs were Saccharomycetales, mostly in the Kazachstania genus. No Saccharomycetales species was shared by all the sourdoughs, whereas five other fungal species, mainly known plant pathogens, were found in all sourdoughs. Interestingly, Saccharomyces cerevisiae, known as "baker's yeast," was identified as the dominant species in only one sourdough. By contrast, five Kazachstania species were identified as the dominant sourdough species, including one recently described Kazachstania species, Kazachstania saulgeensis and an undescribed Kazachstania sp. Sourdoughs from farmer-bakers harbored Kazachstania bulderi, Kazachstania unispora and two newly described Kazachstania species, while sourdough from bakers mostly carried Kazachstania humilis as the dominant species. Such yeast diversity has not been found in sourdoughs before, highlighting the need to maintain different traditional food practices to conserve microbial diversity.
RESUMEN
Six yeast strains representing two novel Wickerhamiella species were isolated from plants and insects collected in Costa Rica, Brazil, and French Guiana. They belong to a subclade containing Wickerhamiella domercqiae and Wickerhamiella bombiphila, and differ by approximately 12â% in the D1/D2 sequences of the large subunit rRNA gene from these species. The intergenic spacer (ITS) regions of the two novel species differ by around 19 and 27â%, respectively, from those of W. domercqiae. The novel species exhibit 5â% divergence in the D1/D2 sequences among them (around 4â% in the ITS). The names Wickerhamiella dianesei f.a., sp. nov. and Wickerhamiella kurtzmanii f.a., sp. nov. are proposed to accommodate these species, for which a sexual cycle has not been observed. Wickerhamiella dianesei was isolated from the stingless bee, Trigona fulviventris, collected in an Asteraceae flower in Costa Rica, and from leaves of Sabicea brasiliensis (Rubiaceae) and a flower of Byrsonima crassifolia (Malpighiaceae) in Brazil. Wickerhamiellsa kurtzmanii was isolated from a flower of Ipomoea batatoides (Convolvulaceae) in Costa Rica, the surface of a fruit of B. crassifolia in Brazil, and flowers in French Guiana. The type strains are Wickerhamiella dianesei UWOPS 00-107.1T (=CBS 14185=NRRL Y-63789; Mycobank number MB 827008) and Wickerhamiella kurtzmanii UWOPS 00-192.1T (=CBS 15383=NRRL Y-63979; MB 827011).
Asunto(s)
Abejas/microbiología , Flores/microbiología , Filogenia , Hojas de la Planta/microbiología , Saccharomycetales/clasificación , Animales , Asteraceae/microbiología , Composición de Base , Brasil , Costa Rica , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Guyana Francesa , Ipomoea/microbiología , Malpighiaceae/microbiología , Técnicas de Tipificación Micológica , Saccharomycetales/genética , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia de ADNRESUMEN
Analysis of yeasts isolated from various biotopes in French Guiana led to the identification of two strains isolated from flowers and designated CLIB 1634T and CLIB 1707T. Comparison of the D1/D2 domain of the large subunit (LSU D1/D2) rRNA gene sequences of CLIB 1634T and CLIB 1707T to those in the GenBank database revealed that these strains belong to the Starmerella clade. Strain CLIB 1634T was shown to diverge from the closely related Starmerella apicola type strain CBS 2868T with a sequence divergence of 1.34 and 1.30â%, in the LSU D1/D2 rRNA gene and internal transcribed spacer (ITS) sequences respectively. Strain CLIB 1634T and Candida apicola CBS 2868T diverged by 3.81 and 14.96â% at the level of the protein-coding gene partial sequences EF-1α and RPB2, respectively. CLIB 1707T was found to have sequence divergence of 3.88 and 9.16â% in the LSU D1/D2 rRNA gene and ITS, respectively, from that of the most closely related species Starmerella ratchasimensis type strain CBS 10611T. The species Starmerella reginensis f.a., sp. nov. and Starmerella kourouensis f.a., sp. nov. are proposed to accommodate strains CLIB 1634T (=CBS 15247T) and CLIB 1707T (=CBS 15257T), respectively.
Asunto(s)
Flores/microbiología , Filogenia , Saccharomycetales/clasificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Guyana Francesa , Genes Fúngicos , Técnicas de Tipificación Micológica , Factor 1 de Elongación Peptídica/genética , Saccharomycetales/genética , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia de ADNRESUMEN
During a survey of the yeast community associated with the phylloplane of corn in Thailand, a basidiomycetous yeast strain belonging to the genus Papiliotrema was isolated. Analyses of the D1/D2 domains of the 26S (LSU) rRNA gene and complete ITS region supported the recognition of a novel species, for which the name Papiliotrema plantarum sp. nov. is proposed (type strain DMKU-CP801T=CBS 15220T=PYCC 7257T). Another strain of P. plantarum sp. nov., isolated in French Guiana, was found to be sexually compatible with the Thai isolate and mycelium with clamp connections, basidia and basidiospores were observed in culture. The basidial morphology of P. plantarum combined features previously observed for Papiliotrema bandonii and Papiliotrema fuscus, which represent the only sexual species hitherto known in the genus, i.e. transversely septate basidia, with sexual structures of the Tremella type.
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Basidiomycota/clasificación , Filogenia , Hojas de la Planta/microbiología , Zea mays/microbiología , Basidiomycota/genética , Basidiomycota/aislamiento & purificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Guyana Francesa , Técnicas de Tipificación Micológica , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Esporas FúngicasRESUMEN
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.
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Microbiología de Alimentos/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Levaduras/aislamiento & purificación , Microbiología de Alimentos/instrumentación , Levaduras/química , Levaduras/clasificaciónRESUMEN
Kazachstania saulgeensis is a recently described species isolated from French organic sourdough. Here, we report the high quality genome sequence of a monosporic segregant of the type strain of this species, CLIB 1764T (= CBS 14374T). The genome has a total length of 12.9 Mb and contains 5326 putative protein-coding genes, excluding pseudogenes and transposons. The nucleotide sequences were deposited into the European Nucleotide Archive under the genome assembly accession numbers FXLY01000001-FXLY01000017.
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During studies of the yeast diversity associated with rotting wood in Brazil and fruits, plants and insects in French Guiana, three strains of a new species were isolated. Analysis of the sequences of the internal transcribed spacer (ITS)-5.8S and D1/D2 domains of the large subunit of the rRNA gene showed that this species belongs to the genus Hyphopichia and its closest relative is Candida homilentoma. These species differ by 44 nucleotide substitutions in D1/D2 sequences. A new species Hyphopichia buzzinii f. a., sp. nov., is proposed to accommodate these isolates. The type strain of Hyphopichia buzzinii sp. nov. is CLIB 1739T (=CBS 14300T = UFMG-CM-Y6121T; MycoBank number is MB 815609). In addition, we isolated 11 strains of C. homilentoma from rotting wood, leaf surfaces, and water bodies in Brazil, and these strains when crossed among one another and with the type strain (CBS 6312T) of this species, produced hat-shaped ascospores typical of the genus Hyphopichia. We describe the teleomorph of C. homilentoma as a new combination, Hyphopichia homilentoma comb. nov. (type strain CBS 6312T; MycoBank number is MB 820009). We also propose to transfer the other six Candida species of the Hyphopichia clade to this genus as new combinations. Hyphopichia homilentoma produced ethanol and xylitol from D-xylose whereas H. buzzinii was only able to convert this pentose to xylitol.
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Candida , ADN de Hongos , Técnicas de Tipificación Micológica , Animales , Brasil , Candida/genética , Candida/metabolismo , ADN Espaciador Ribosómico , Filogenia , Análisis de Secuencia de ADNRESUMEN
Geotrichum candidum is a ubiquitous yeast and an essential component in the production of many soft cheeses. We developed a multilocus sequence typing (MLST) scheme with five retained loci (NUP116, URA1, URA3, SAPT4 and PLB3) which were sufficiently divergent to distinguish 40 sequence types (STs) among the 67 G. candidum strains tested. Phylogenetic analyses defined five main clades; one clade was restricted to environmental isolates, three other clades included distinct environmental isolates and dairy strains, while the fifth clade comprised 34 strains (13 STs), among which all but two were isolated from milk, cheese or the dairy environment. These findings suggest an adaptation to the dairy ecosystems by a group of specialized European G. candidum strains. In addition, we developed a polymerase chain reaction inter-long terminal repeat scheme, a fast and reproducible random amplification of polymorphic DNA-like method for G. candidum, to type the closely related dairy strains, which could not be distinguished by MLST. Overall, our findings distinguished two types of dairy strains, one forming a homogeneous group with little genetic diversity, and the other more closely related to environmental isolates. Neither regional nor cheese specificity was observed in the dairy G. candidum strains analysed. This present study sheds light on the genetic diversity of both dairy and environmental strains of G. candidum and thus extends previous characterizations that have focused on the cheese isolates of this species. Copyright © 2016 John Wiley & Sons, Ltd.
Asunto(s)
ADN de Hongos/genética , Variación Genética , Geotrichum/genética , Tipificación de Secuencias Multilocus , Filogenia , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADNRESUMEN
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 large subunit (LSU) rRNA gene and the internal transcribed spacer (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 barnettii. Analysis of protein coding sequences of RPB1, RPB2 and EF-1α 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: Kazachstania 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 K. 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, Kazachstania 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.
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Filogenia , Saccharomycetales/clasificación , Brasil , Pan/microbiología , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Francia , Genes Fúngicos , Técnicas de Tipificación Micológica , Factor 1 de Elongación Peptídica/genética , ARN Polimerasa II/genética , ARN Ribosómico/genética , Saccharomycetales/genética , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia de ADN , Madera/microbiologíaRESUMEN
Culture collections contain indispensable information about the microorganisms preserved in their repositories, such as taxonomical descriptions, origins, physiological and biochemical characteristics, bibliographic references, etc. However, information currently accessible in databases rarely adheres to common standard protocols. The resultant heterogeneity between culture collections, in terms of both content and format, notably hampers microorganism-based research and development (R&D). The optimized exploitation of these resources thus requires standardized, and simplified, access to the associated information. To this end, and in the interest of supporting R&D in the fields of agriculture, health and biotechnology, a pan-European distributed research infrastructure, MIRRI, including over 40 public culture collections and research institutes from 19 European countries, was established. A prime objective of MIRRI is to unite and provide universal access to the fragmented, and untapped, resources, information and expertise available in European public collections of microorganisms; a key component of which is to develop a dynamic Information System. For the first time, both culture collection curators as well as their users have been consulted and their feedback, concerning the needs and requirements for collection databases and data accessibility, utilised. Users primarily noted that databases were not interoperable, thus rendering a global search of multiple databases impossible. Unreliable or out-of-date and, in particular, non-homogenous, taxonomic information was also considered to be a major obstacle to searching microbial data efficiently. Moreover, complex searches are rarely possible in online databases thus limiting the extent of search queries. Curators also consider that overall harmonization-including Standard Operating Procedures, data structure, and software tools-is necessary to facilitate their work and to make high-quality data easily accessible to their users. Clearly, the needs of culture collection curators coincide with those of users on the crucial point of database interoperability. In this regard, and in order to design an appropriate Information System, important aspects on which the culture collection community should focus include: the interoperability of data sets with the ontologies to be used; setting best practice in data management, and the definition of an appropriate data standard.
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Raffia wine is a traditional alcoholic beverage produced in several African countries where it plays a significant role in traditional customs and population diet. Alcoholic fermentation of this beverage is ensured by a complex natural yeast flora which plays a decisive role in the quality of the final product. This present study aims to evaluate the distribution and the diversity of the yeast strains isolated in raffia wine from four sampling areas (Abengourou, Alépé, Grand-Lahou and Adzopé) in Côte d'Ivoire. Based on the D1/D2 domain of the LSU rDNA sequence analysis, nine species belonging to six genera were distinguished. With a percentage of 69.5 % out of 171 yeast isolates, Saccharomyces cerevisiae was the predominant species in the raffia wine, followed by Kodamaea ohmeri (20.4 %). The other species isolated were Candida haemulonii (4.1 %), Candida phangngensis (1.8 %), Pichia kudriavzevii (1.2 %), Hanseniaspora jakobsenii (1.2 %), Candida silvae (0.6 %), Hanseniaspora guilliermondii (0.6 %) and Meyerozyma caribbica (0.6 %). The molecular characterization of S. cerevisiae isolates at the strain level using the PCR-interdelta method revealed the presence of 21 profiles (named I to XXI) within 115 isolates. Only four profiles (I, III, V and XI) were shared by the four areas under study. Phenotypic characterization of K. ohmeri strains showed two subgroups for sugar fermentation and no diversity for the nitrogen compound assimilations and the growth at different temperatures.