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1.
Int J Syst Evol Microbiol ; 70(9): 4908-4913, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32716833

RESUMO

The majority of Suhomyces species have been isolated from fungus-feeding insects and particularly from the gut of beetles. In the present study, seven yeast strains were isolated from the gut of Drosophila species feeding on gleba, the spore-bearing inner mass, of a stinkhorn mushroom belonging to the family Phallaceae. Based on phenotypic, biochemical characterization and sequence analysis of the D1/D2 region of the large subunit rRNA gene and the internal transcribed spacer (ITS) region, two of these yeast strains, DGY3 and DGY4, represented a novel species of the genus Suhomyces. The novel species is closely related to an undescribed species of Candida ST-370 (DQ404513) and with Suhomyces canberraensis, wherein, the novel species differs from S. canberraensis by 40 nucleotide substitutions and three gaps (7.7 % sequence variation) in the D1/D2 region and 50 nucleotide substitutions and seven gaps (13.7 % sequence variation) in the ITS region. Several morphological and physiological differences were also observed between S. canberraensis and the strains obtained during this study. These data support the proposal of Suhomyces drosophilae as a novel species, with DGY3T as the holotype and CBS 16329T and MCC 1871T as ex-type strains.


Assuntos
Drosophila/microbiologia , Filogenia , Saccharomycetales/classificação , Agaricales , Animais , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Índia , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação
2.
Int J Syst Evol Microbiol ; 70(7): 4378-4383, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32584748

RESUMO

Four isolates of two novel ascosporogenous species belonging to the clade Starmera were obtained from cactus tissues and rotting wood in Brazil. Results of analyses of the sequences of the ITS and D1/D2 domains of the large subunit rRNA gene indicated that the two isolates of the cactophilic species are related to Starmera caribaea and Starmera pilosocereana, yeasts that are associated with cacti and require an organic source of sulfur for growth. We propose the novel species Starmera foglemanii sp. nov. (CBS 16113T; MycoBank number: MB 834400) to accommodate these isolates. The other two isolates are phylogenetically related to Candida dendrica, Candida laemsonensis and Candida berthetii, also in the Starmera clade. The novel species name Starmera ilhagrandensis sp. nov. (CBS 16316T; MycoBank number: MB 834402) is proposed for this species.


Assuntos
Cactaceae/microbiologia , Filogenia , Saccharomycetales/classificação , Madeira/microbiologia , Brasil , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA
3.
Int J Syst Evol Microbiol ; 70(7): 4217-4223, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32589574

RESUMO

Five yeast strains were isolated from the gut of the groundbeetle Pterostichus gebleri and rotting wood, which were collected from two different localities in China. These strains were identified as representing two novel species of the genus Blastobotrys through comparison of sequences in the D1/D2 domains of the LSU rRNA gene and other taxonomic characteristics. Blastobotrys baotianmanensis sp. nov. produces two to three spherical ascospores per ascus, and is most closely related to the type strains of B. elegans, B. capitulata, B. arbuscula, and an undescribed species represented by strain BG02-7-20-006A-3-1. Blastobotrys baotianmanensis sp. nov. differed from these strains by 3.6-8.4 % divergence (21-46 substitutions and 0-4 gaps) in the D1/D2 sequences. Blastobotrys xishuangbannaensis f.a., sp. nov. is closely related to B. nivea, B. elegans and B. aristata but the formation of ascospores was not observed on various sporulation media, and it differed from its relatives by 6.2-8.5 % divergence (34-43 substitutions and 2-6 gaps) in the D1/D2 sequences. The holotype of Blastobotrys baotianmanensis sp. nov. is NYNU 1581 and the holotype of Blastobotrys xishuangbannaensis f.a., sp. nov. is NYNU 181030.


Assuntos
Besouros/microbiologia , Filogenia , Saccharomycetales/classificação , Madeira/microbiologia , Animais , China , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Esporos Fúngicos
4.
Int J Food Microbiol ; 325: 108647, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32361480

RESUMO

Yeasts are one of the main organisms in the food industry and effective components of many ecosystems. The method for identifying and detecting certain yeast species or strains is a crucial step for the food industry and should be simple, reliable, fast, and inexpensive. In our study, inter-priming binding sites (iPBS) retrotransposon marker system was employed to elucidate the genetic variability at intraspecies and interspecies levels among 112 yeast strains belonging to eight species previously obtained from fermented foods. The molecular identification of yeast strains was firstly confirmed by sequencing the D1/D2 domain of the 26S rRNA. The eight selected retrotransposon-based primers produced 278 bands, all of which were polymorphic with an average of 34.75 polymorphic fragments per primer. The averages of polymorphism information contents and the resolving power values for the iPBS marker system were 0.23 and 10.11, respectively. The genetic parameters within each yeast species obtained from iPBS markers were observed as; the percentage of polymorphic loci for each species ranging from 19.23% to 71.21%, Nei's gene diversity from 0.085 to 0.228, while Shannon's information index values ranging from 0.125 to 0.349. The value of gene flow (0.09) and genetic variation among the populations (0.85) showed higher genetic variation among the species. UPGMA analyses demonstrated considerable genetic variability in the yeast strains, clustered them according to their species, and revealed the intraspecific variation. Each of the selected iPBS primer provided enough species-discrimination. Present evaluations suggest the utility of iPBS marker system to estimate the genetic variation of yeast strains. This study is a preliminary point for further studies on the identification methodology, and population genetics of yeast species having importance in the food industry with iPBS markers.


Assuntos
Retroelementos/genética , Saccharomycetales/genética , Fermento Seco/genética , Sítios de Ligação , Primers do DNA/genética , Ecossistema , Variação Genética/genética , Filogenia , Polimorfismo Genético/genética , Saccharomycetales/classificação
5.
Int J Syst Evol Microbiol ; 70(5): 3491-3496, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32374249

RESUMO

During studies on the endophytic yeast communities associated with fruits from Vietnam, three fermenting yeast strains were isolated from fruits of the coconut palm (Cocos nucifera). Phylogenetic analysis based on the sequences of the ITS regions and D1/D2 domains of the large subunit rRNA gene showed that these strains represented a single species of the Yamadazyma clade that was distinct from the other related species. The new species represented a basal branch of the clade formed by the Yamadazyma species i.e. Y. insecticola and Y. takamatsuzukensis. Based on the phylogenetic analysis and phenotypic characteristics, the studied strains were assigned to a novel species of the genus Yamadazyma, for which the name Yamadazyma cocois f.a., sp. nov. is proposed. The holotype is VCIM 4241, with the ex-type cultures VTCC 920004=VKM Y-3049=KBP Y-6091 code 17-68. The MycoBank number is MB 834435.


Assuntos
Cocos/microbiologia , Filogenia , Saccharomycetales/classificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Fermentação , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Vietnã
6.
Int J Syst Evol Microbiol ; 70(5): 3379-3390, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375944

RESUMO

During a survey of fungi in native forests in Chile, several unidentified isolates of Diaporthe were collected from different hosts. The isolates were characterized based on DNA comparisons, morphology, culture characteristics and host affiliation, in accordance with previous descriptions. Phylogenetic analysis of the ITS region, combined with partial tub2 and tef1 genes, showed that the isolates formed three distinct groups representing three new taxa. The three new species of Diaporthe, Diaporthe araucanorum on Araucaria araucana, Diaporthe foikelawen on Drimys winteri and Diaporthe patagonica on Aristotelia chilensis are described and illustrated in the present study.


Assuntos
Florestas , Filogenia , Saccharomycetales/classificação , Chile , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Genes Fúngicos , RNA Ribossômico 16S/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA
7.
Int J Syst Evol Microbiol ; 70(4): 2596-2601, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32134373

RESUMO

Seven yeast strains, DMKU VGT1-14T, DMKU VGT1-19T, DMKU-JMGT1-28, DMKU-JMGT1-32, DMKU VGT2-06, DMKU VGT2-19 and DMKU VGT6-14, were isolated from a grease trap in Thailand and two strains, SJ-1 and SN-102 were isolated from the sea surface microlayer in Taiwan. On the basis of phenotypic characteristics and sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, these strains represented two novel yeast species of the genus Wickerhamiella. In terms of pairwise sequence similarity, four strains, DMKU VGT1-14, DMKU-JMGT1-32, DMKU VGT6-14 and SN-102, were closely related to Wickerhamiella infanticola NRRL Y-17858T but differed by 13 nucleotide substitutions with one gap (2.46 %) in the D1/D2 domain of the LSU rRNA gene and 15 nucleotide substitutions with 23 gaps (4.2 %) in the ITS region. The strains DMKU VGT1-19T, DMKU-JMGT1-28, DMKU VGT2-06, DMKU VGT2-19 and SJ-1, differed from the type strain of the most closely related species, Wickerhamiella sorbophila NRRL Y-7921T, by nine nucleotide substitutions with one gap (1.66 %) in the D1/D2 domain of the LSU rRNA gene and nine nucleotide substitutions with 17 gaps (2.52%) in the ITS region. Hence, the names Wickerhamiella osmotolerans sp. nov. and Wickerhamiella tropicalis sp. nov. are proposed to accommodate these species in the genus Wickerhamiella. The holotypes are W. osmotolerans DMKU VGT1-14T (ex-type strain TBRC 11425=PYCC 8359=CGMCC 2.6179; Mycobank number 833394) and W. tropicalis DMKU VGT1-19T (ex-type strain TBRC 11426=PYCC 8360=CGMCC 2.6180; Mycobank number 833393).


Assuntos
Filogenia , Saccharomycetales/classificação , Água do Mar/microbiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Taiwan , Tailândia
8.
Int J Syst Evol Microbiol ; 70(4): 2677-2681, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32207678

RESUMO

Six strains of a novel yeast species were isolated from tree bark collected in the Atlantic Forest and the Amazon Rainforest in Brazil. Analyses of the sequences of D1/D2 domains of the large subunit rRNA gene showed that the strains belong to a species in the genus Zygotorulaspora. The species differed by 5.54 % sequence divergence (25 substitutions and five indels out of 542 bp) in the D1/D2 sequences from Zygotorulaspora mrakii, its closest relative. The ITS sequence of the type strain of the novel species differs by 27-69 nucleotide substitutions/indels from the other Zygotorulaspora species. The novel species is able to grow on trehalose, maltose, l-sorbose, inulin and at 37 °C, which are negative in Z. mrakii. The name Zygotorulaspora cariocana sp. nov. is proposed. The holotype of Z. cariocana sp. nov. is CBS 16118T. The MycoBank number is MB 833702.


Assuntos
Filogenia , Casca de Planta/microbiologia , Saccharomycetales/classificação , Brasil , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Floresta Úmida , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Árvores/microbiologia
9.
Int J Syst Evol Microbiol ; 70(2): 1372-1397, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32122458

RESUMO

Fourteen novel lipomycetaceous yeasts species were isolated from soil samples collected from the Hokkaido, Chiba and Okinawa prefectures of Japan. Phylogenetic analyses of the D1/D2 domains of the large subunit rRNAs and translation elongation factor 1 alpha genes (TEF1-α) revealed that five strains of two species from the soil in Furano-shi, Hokkaido were related to Dipodascopsis anomala and 29 strains representing 12 species from soils in Kamogawa-shi, Chiba and Iriomote Island, Okinawa were in the Myxozyma clade. The two species of Dipodascopsis form globose or ellipsoid ascospores in their sac-like ascus and pseudohyphae. Furthermore, these species produce ascospores in their pseudohyphae and do not produce an acicular ascus, which is common among the three species including D. anomala. Therefore, we propose transferring D. anomala to the genus Babjevia and amending Babjevia. Two novel species were described and included in the genus Babjevia: Babjevia hyphoforaminiformans sp. nov. (holotype NBRC 111233; MycoBank no. MB 829051) and Babjevia hyphasca sp. nov. (holotype NBRC 112965; MycoBank no. MB 829053). The 12 species in the Myxozyma clade produce neither ascospores nor pseudohyphae and have different characteristics in assimilating several carbon sources from each other. Thus, we propose that the novel species of Lipomyces be classified as forma asexualis (f.a.). From Kamogawa-shi, Chiba (19 strains representing five species): Lipomyces melibiosiraffinosiphilus f.a., sp. nov. (holotype NBRC 111411; MycoBank no. MB 829034), Lipomyces kiyosumicus f.a., sp. nov. (holotype NBRC 111424; MycoBank no. MB 829035), Lipomyces chibensis f.a., sp. nov. (holotype NBRC 111413; MycoBank no. MB 829036), Lipomyces kamogawensis f.a., sp. nov. (holotype NBRC 112967; MycoBank no. MB 829037), Lipomyces amatsuensis f.a., sp. nov. (holotype NBRC 111420; MycoBank no. MB 829041). From Iriomote island, Okinawa (10 strains representing seven species): Lipomyces taketomicus f.a., sp. nov. (holotype NBRC 112966; MycoBank no. MB 829042), Lipomyces yaeyamensis f.a., sp. nov. (holotype NBRC 110433; MycoBank no. MB 829050), Lipomyces iriomotensis f.a., sp. nov. (holotype NBRC 110436; MycoBank no. MB 829045), Lipomyces haiminakanus f.a., sp. nov. (holotype NBRC 110435; MycoBank no. MB 829046), Lipomyces komiensis f.a., sp. nov. (holotype NBRC 110440; MycoBank no. MB 829047), Lipomyces nakamensis f.a., sp. nov. (holotype NBRC 110434; MycoBank no. MB 829048), Lipomyces sakishimensis f.a., sp. nov. (holotype NBRC 110439; MycoBank no. MB 829049).


Assuntos
Lipomyces/classificação , Filogenia , Microbiologia do Solo , DNA Fúngico/genética , Genes Fúngicos , Japão , Lipomyces/isolamento & purificação , Técnicas de Tipagem Micológica , Fator 1 de Elongação de Peptídeos/genética , Fenótipo , Saccharomycetales/classificação , Análise de Sequência de DNA , Esporos Fúngicos
10.
Yeast ; 37(4): 313-320, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32061177

RESUMO

The Wickerhamiella and Starmerella genera form a clade (W/S clade) that branches close to Yarrowia lipolytica in the Saccharomycotina species tree. It comprises approximately 90 recognized species and 50 putative new species not formally described yet. The large majority of the members of the W/S clade are ecologically associated with flowers and floricolous insects. Many species exhibit unusual metabolic traits, like fructophily and the production of sophorolipids, which are glycolipids that can be used as environmentally friendly biosurfactants. Genomic data have not only firmly established the W/S clade but have also revealed a tumultuous evolution of metabolism marked by losses and gains of important metabolic pathways, among which alcoholic fermentation. Possibly the most surprising finding brought to light by comparative genomics concerned the large number of genes acquired by some species of the W/S clade from bacteria through horizontal gene transfer, many of which were shown to be functional in their new setting. This was facilitated by the genetic tractability of one species in the clade, Starmerella bombicola, which is used for the industrial production of sophorolipids. We suggest that high-density coverage of genome sequencing in this clade, combined with the possibility to conduct molecular genetics experiments in at least one species, has the potential to set the stage for yet more exciting discoveries concerning the evolution of yeast metabolism.


Assuntos
DNA Fúngico/isolamento & purificação , Saccharomycetales/classificação , Saccharomycetales/genética , Animais , DNA Fúngico/genética , Evolução Molecular , Flores/microbiologia , Transferência Genética Horizontal , Glicolipídeos/biossíntese , Glicolipídeos/genética , Insetos/microbiologia , Redes e Vias Metabólicas , Filogenia , Saccharomycetales/isolamento & purificação
11.
Int J Syst Evol Microbiol ; 70(4): 2420-2425, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32100691

RESUMO

Yeast strains belonging to a novel anamorphic yeast species were isolated from subsoil groundwater contaminated with hydrocarbons in a metal working factory located in northern Spain, and from a human infection in the USA. Comparison of ITS sequences between the isolates revealed 0.2 % divergence between the Spanish isolates and 0.46 % divergence between those and the USA isolate. Phylogenetic analysis based on the D1/D2 domains of the LSU rRNA gene showed that these isolates belong to the Wickerhamiella clade with W. sorbophila and W. infanticola as their closest relatives. Sequence divergence between the new isolates and W. sorbophila and W. infanticola was 1.97 and 1.79 %, respectively. The isolates in the novel species are not fermentative and pseudohyphae were not produced. Sexual reproduction was not observed for individual isolates or in mixtures of isolates. Conjugation between the isolates in the novel species and close relatives W. sorbophila and W. infanticola was not observed. These data support the proposal of Wickerhamiella verensis as a novel species, with CECT 12028T as the holotype.


Assuntos
Água Subterrânea/microbiologia , Micoses/microbiologia , Filogenia , Saccharomycetales/classificação , DNA Fúngico/genética , Fermentação , Georgia , Humanos , Hidrocarbonetos , Lactente , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Espanha , Poluentes Químicos da Água
12.
Antonie Van Leeuwenhoek ; 113(5): 663-676, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31897851

RESUMO

Using electrophoretic karyotyping, RAPD fingerprinting and phylogenetic analysis of ribosomal RNA gene sequences, twenty-six Vanderwaltozyma strains were studied. Out of 19 strains isolated in mountainous areas of Taiwan, eighteen strains were isolated from soil and one strain was isolated from the fruiting body of mushroom, six were identified as V. polyspora and three as V. verrucispora. Based on the results of a multigene sequence analysis (D1/D2, ITS and mitochondrial COX II gene) and DNA-DNA reassociation, three new ascosporic members of the genus Vanderwaltozyma are formally described: V. huisunica sp. nov. (GA1S06T = CBS 12250T = BCRC 23260T), V. meishanica sp. nov. (EN4S02T = CBS 12249T = BCRC 23255T) and V. molinica sp. nov. (GJ8S05T = CBS 12251T = BCRC 23264T), and the holotypes of these novel species are assigned as BCRC 23260T, BCRC 23255T and BCRC 23264T, respectively.


Assuntos
Saccharomycetales , Classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Fúngicos , Genes de RNAr , Técnicas de Tipagem Micológica , Técnica de Amplificação ao Acaso de DNA Polimórfico , Saccharomycetales/classificação , Saccharomycetales/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Microbiologia do Solo , Taiwan
13.
Int J Syst Evol Microbiol ; 70(3): 2103-2107, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995468

RESUMO

Four strains of anamorphic yeasts isolated from the fruiting bodies of mushrooms collected in Taiwan were found to represent two novel yeast species belonging to the genus Teunomyces, which was formally known as the Candida kruisii clade. Strains NY13M09T and NY14M14 were related to the type strains of Teunomyces panamensis, T. pallodes, T. tritomae and T. lycoperdinae, and strains GG4M07T and GG6M14 were related to T. kruisii NRRL Y-17087T and T. cretensis NRRL Y-27777T. However, strains NY13M09T and NY14M14 differed from their closest phylogenetic neighbours by 2.9-3.7 % in the D1/D2 domain sequence of the LSU rRNA gene and by 6.6-13.7 % in the internal transcribed spacer (ITS); GG4M07T and GG6M14 differed from their closest known species by 2.4 % in the D1/D2 domain sequence of the LSU rRNA gene and by 8.7-10.0 % in the ITS. Meanwhile, these strains were also clearly distinguished from their closest relatives based on the results of physiological tests. Based on the characteristics described above, the strains could be regarded as representing two novel species of the genus Teunomyces, for which the names Teunomyces basidiocarpi sp. nov. and Teunomyces luguensis sp. nov. are proposed. The holotypes are Teunomyces basidiocarpi BCRC 23475T and Teunomyces luguensis BCRC 23476T.


Assuntos
Agaricales , Filogenia , Saccharomycetales/classificação , Composição de Bases , DNA Fúngico/genética , Técnicas de Tipagem Micológica , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Taiwan
14.
Int J Syst Evol Microbiol ; 70(1): 199-203, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31596197

RESUMO

Two yeast strains, DMKU-WBL1-3 and DMKU GT3-16, were obtained from grease samples collected from grease traps at the Kasetsart University canteen, Thailand. Pairwise sequence analysis indicated that the strains were closely related to Candida cylindracea NRRL Y-17506T, but differed by 11 and 35 nucleotide substitutions in the D1/D2 domain of the large subunit (LSU) rRNA gene and the ITS region, respectively. Based on sequence divergences, the novel species was distinguished from C. cylindracea. The results of phylogenetic analysis based on the concatenated sequences from small subunit rRNA, ITS region and LSU rRNA genes showed that the two strains and C. cylindracea NRRL Y-17506T formed a distinct lineage related to the genus Babjeviella. A novel genus, Limtongozyma, is proposed to accommodate these clade members. Hence, Candida cylindracea NRRL Y-17506T is transferred to this genus and assigned as the type species of the genus. The holotype of Limtongozyma siamensis is DMKU-WBL1-3.


Assuntos
Filogenia , Saccharomycetales/classificação , Candida/classificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , RNA Ribossômico/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Tailândia
15.
Int J Food Microbiol ; 316: 108441, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31778839

RESUMO

Even though non-Saccharomyces yeasts were regarded as spoilage microorganisms for a long time, their abilities to improve and diversify the aromatic profile of wines are now well recognized. Consequently, their use in combination with S. cerevisiae strains during winemaking has attracted substantial attention over the last decade. However, our limited understanding of the metabolism and physiology of these species remains a barrier to promoting efficient exploitation of their full potential. In this study, we further explored the metabolism involved in the production of fermentative volatile compounds of two commercial non-Saccharomyces strains, T. delbrueckii Biodiva™ and M. pulcherrima Flavia®, in comparison with the reference wine yeast S. cerevisiae Lalvin EC1118®. After growing these strains in the presence of 24 different N-compounds, particular attention was paid to the influence of the nitrogen source on the profile of aroma compounds synthesized by these yeasts (higher alcohols and acids, medium-chain fatty acids and their acetate or ethyl esters derivatives). A comprehensive analysis of the dataset showed that these three species were able to produce all the fermentative aromas, regardless of the nitrogen source, demonstrating the key contribution of the central carbon metabolism to the formation of volatile molecules. Nevertheless, we also observed some specific phenotypic traits for each of the strains in their assimilation capacities for the various nitrogen nutrients as well as in their response to the nature of the nitrogen source in terms of the production of volatile molecules. These observations revealed the intricacy and interconnection between the networks involved in nitrogen consumption and aroma production. These differences are likely related to the genetic backgrounds of the strains. Overall, this study expands our understanding of the metabolic processes responsible for the formation of volatile compounds during wine fermentation and their variations according to species and the nature of the nitrogen source. This knowledge provides a new platform for the more efficient exploitation of non-Saccharomyces strains during winemaking, improving the management of the fermentation.


Assuntos
Nitrogênio/metabolismo , Odorantes , Saccharomycetales/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Fermentação , Odorantes/análise , Fenótipo , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/classificação , Especificidade da Espécie , Compostos Orgânicos Voláteis/análise , Vinho/análise , Vinho/microbiologia
16.
Folia Microbiol (Praha) ; 65(2): 381-392, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31401763

RESUMO

Citrus black spot (CBS) and post-bloom fruit drop (PFD), caused by Phyllosticta citricarpa and Colletotrichum abscissum, respectively, are two important citrus diseases worldwide. CBS depreciates the market value and prevents exportation of citrus fruits to Europe. PFD under favorable climatic conditions can cause the abscission of flowers, thereby reducing citrus production by 80%. An ecofriendly alternative to control plant diseases is the use of endophytic microorganisms, or secondary metabolites produced by them. Strain LGMF1631, close related to Diaporthe cf. heveae 1, was isolated from the medicinal plant Stryphnodendron adstringens and showed significant antimicrobial activity, in a previous study. In view of the potential presented by strain LGMF1631, and the absence of chemical data for secondary metabolites produced by D. cf. heveae, we decided to characterize the compounds produced by strain LGMF1631. Based on ITS, TEF1, and TUB phylogenetic analysis, strain LGMF1631 was confirmed to belong to D. cf. heveae 1. Chemical assessment of the fungal strain LGMF1631 revealed one new seco-dihydroisocoumarin [cladosporin B (1)] along with six other related, already known dihydroisocoumarin derivatives and one monoterpene [(-)-(1S,2R,3S,4R)-p-menthane-1,2,3-triol (8)]. Among the isolated metabolites, compound 5 drastically reduced the growth of both phytopathogens in vitro and completely inhibited the development of CBS and PFD in citrus fruits and flowers. In addition, compound 5 did not show toxicity against human cancer cell lines or citrus leaves, at concentrations higher than used for the inhibition of the phytopathogens, suggesting the potential use of (-)-(3R,4R)-cis-4-hydroxy-5-methylmellein (5) to control citrus diseases.


Assuntos
Ascomicetos/efeitos dos fármacos , Citrus/microbiologia , Fungicidas Industriais/farmacologia , Isocumarinas/farmacologia , Saccharomycetales/química , Ascomicetos/fisiologia , Colletotrichum/efeitos dos fármacos , Colletotrichum/fisiologia , Fabaceae/microbiologia , Frutas/microbiologia , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Isocumarinas/química , Isocumarinas/metabolismo , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Saccharomycetales/classificação , Saccharomycetales/genética , Saccharomycetales/isolamento & purificação
17.
Microb Pathog ; 138: 103811, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31644930

RESUMO

The bacterial cell communication also termed as Quorum sensing (QS) system was involved in the expression of several virulence traits during Pseudomonas infection. The attenuating of this bacterial cell communication system is an attractive approach for the management of bacterial infections without the complication of resistance development. In this respect, the marine environment has gained significant attention due to its biodiversity and as a source of novel bioactive compounds. The present study aimed to screening effective QS inhibitors from marine associated fungal species for QS inhibitors. Twelve morphologically distinct fungal isolates were isolated from the wood of Avicennia marina from marine ecosystem. The anti-QS potential of fungal crude extract from was investigated in biosensor strain and test bacterium, Chromobacterium violaceum and Pseudomonas aeruginosa PAO1, respectively. Promising anti-QS activity was observed in the crude extract of one of the fungal isolate and identified by molecular characterization using internal transcribed spacer (ITS) region as Blastobotrys parvus PPR3. The anti-virulence and antibiofilm effects of ethyl acetate fractions from PPR3 against P. aeruginosa PAO1 were evaluated. The fungal metabolites responsible for the anti-QS activity of fungal crude extract was identified using gas chromatography-mass spectrometry (GC-MS). Furthermore, molecular docking studies were performed to understand the interaction of bioactive compounds with as receptors of P. aeruginosa PAO1. The crude extract of PPR3 showed reduction in different virulence traits of P. aeruginosa PAO1 such as production of pyocyanin, elastase, protease, chitinase, swimming and swarming motility, biofilm formation, exopolysaccharide production and alginate production at different sub-MIC concentrations. Interaction of bioactive metabolites with LasR and RhlR receptors of P. aeruginosa PAO1 was reported. The findings of the present study suggested that metabolites of B. parvus PPR3 interfere with QS system of P. aeruginosa PAO1 and alters the production of virulence factors.


Assuntos
Antibiose , Organismos Aquáticos , Biofilmes , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum , Saccharomycetales/fisiologia , Antibacterianos/biossíntese , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Modelos Moleculares , Filogenia , Percepção de Quorum/efeitos dos fármacos , Saccharomycetales/classificação , Saccharomycetales/isolamento & purificação , Relação Estrutura-Atividade , Virulência/efeitos dos fármacos
18.
Int J Syst Evol Microbiol ; 70(2): 977-981, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31724935

RESUMO

Strain SY-07 was isolated from decaying leaves of Avicennia marina collected from Syhat mangroves, Dammam city, Arabian Gulf, Saudi Arabia. Phylogenetic analyses of three genes [D1/D2 region of the LSU and SSU rRNA genes and internal transcribed spacer (ITS) region] showed that strain SY-07 represents a novel species of the genus Saturnispora distinct from closely related species. Saturnispora mendoncae was the most closely related species with an LSU gene sequence similarity of 89.3 % (58 nucleotide substitutions and four indels out of 578 nt), 97 % similarity for the SSU gene (42 nucleotide substitutions and 10 indels out of 1614 nt) and 88 % similarity for the ITS region (15 nucleotide substitutions and eight indels out of 430 nt). In addition, strain SY-07 differed from S. mendoncae by its ability to assimilate d-galactose (weak), d-xylose (weak), meso-erythritol (delayed), glucono-δ-lactone, citrate (delayed) and ethylamine. S. mendoncae produced persistent asci that contain two to four spherical ascospores and lacked pseudohyphae, while sexual reproduction was not observed in strain SY-07 and extensive and pseudohyphae were present. Strain SY-07 was able to grow at between 25 and 40 °C, while S. mendoncae did not grow at 37 °C. The name Saturnispora mangrovi f.a., sp. nov. is proposed for strain SY-07. The holotype is CBS 15874, with the ex-type culture AUMC 12005. The MycoBank number for Saturnispora mangrovi f.a., sp. nov. is MB 827036.


Assuntos
Avicennia/microbiologia , Filogenia , Folhas de Planta/microbiologia , Saccharomycetales/classificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Saccharomycetales/isolamento & purificação , Arábia Saudita , Análise de Sequência de DNA , Esporos Fúngicos
19.
J Appl Microbiol ; 128(3): 853-861, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31733170

RESUMO

AIM: The aim of the present study was to investigate the in vitro antioxidant activity of yeast strains isolated from virgin olive oil. METHODS AND RESULTS: The 2,2-diphenyl-1-picryl-hydrazyl (DPPH) free-radical scavenging activity of single cultures of 24 yeast strains belonging to eight species isolated from virgin olive oil was evaluated and compared with that of the reference yeast Saccharomyces boulardii. All the yeasts studied in vitro showed antioxidant activity similar to or superior to that of the reference yeast. The highest antioxidant activity was observed in Nakazawaea wickerhamii, which exceeded the value reached by the reference strain S. boulardii, while the significantly lowest values were observed in the Candida adriatica, Candida diddensiae and Barnettozyma californica strains. Tests performed with virgin olive oil enriched with Wickerhamomyces anomalus and S. boulardii yeast biomasses showed a positive correlation between the microbial biomass used and the percentage of antioxidant activity observed during 60 days of storage. Survival in virgin olive oil was also significantly higher for W. anomalus compared to S. boulardii. CONCLUSIONS: All the oil-borne yeasts studied showed DPPH free-radical scavenging activity in both aqueous and oily media. SIGNIFICANCE AND IMPACT OF THE STUDY: For the first time, the antioxidant activity of the microbiota of virgin olive oil is reported. This activity may indicate the probiotic characteristics of the microbiota.


Assuntos
Antioxidantes/metabolismo , Azeite de Oliva , Saccharomycetales/isolamento & purificação , Saccharomycetales/metabolismo , Biomassa , Compostos de Bifenilo/metabolismo , Microbiologia de Alimentos , Microbiota , Picratos/metabolismo , Probióticos , Saccharomycetales/classificação , Saccharomycetales/crescimento & desenvolvimento
20.
Int J Syst Evol Microbiol ; 70(2): 1158-1165, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31833830

RESUMO

Two yeast strains isolated from soil collected in Hokkaido, Japan, were found to secrete two extracellular lipases that exhibited activities at both 25 and 4 °C. Both strains could utilize olive oil, rapeseed oil, lard and fish oil as sole carbon sources. The similarity of the D1/D2 domain of the large subunit ribosomal RNA (LSU rRNA) sequence of these yeast strains to that of other yeasts in the GenBank database was very low (<96 %). The phylogenetic trees based on the LSU rRNA sequences and translation elongation factor-1-α (tef1-α) sequences indicated that both strains represented a member of the Wickerhamomyces /Candida clade. Sexual reproduction was not observed. The name Wickerhamomyces psychrolipolyticus f.a., sp. nov is proposed for this newly described yeast species producing cold-active lipases. This novel species is distinguishable from the type strains of other related species, Wickerhamomyces alni, Candida ulmi and Candida quercuum due to their abilities to grow at 4 to 30 °C, to produce lipase that is active also at 4 °C and to assimilate soluble starch.


Assuntos
Filogenia , Saccharomycetales/classificação , Microbiologia do Solo , Composição de Bases , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Japão , Lipase , Técnicas de Tipagem Micológica , Fator 1 de Elongação de Peptídeos/genética , Subunidades Ribossômicas Maiores/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Temperatura
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