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1.
Sci Total Environ ; 926: 171786, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508248

RESUMO

Despite the important role that biocrust communities play in maintaining ecosystem structure and functioning in deglaciated barren soil, few studies have been conducted on the dynamics of biotic communities and the impact of physicochemical characteristics in shaping the different successional stages. In this study an integrated approach encompassing physicochemical parameters and molecular taxonomy was used for identifying the indicator taxa and the presence of intra- and inter-kingdom interactions in five different crust/biocrust successional stages: i) physical crust, ii) cyanobacteria-dominated biocrust, iii) cyanobacteria/moss-dominated biocrust, iv) moss-dominated biocrust and v) bryophyte carpet. The phylum Gemmatimonadota was the bacterial indicator taxon in the early stage, promoting both inter- and intra-kingdom interactions, while Cyanobacteria and Nematoda phyla played a pivotal role in formation and dynamics of cyanobacteria-dominated biocrusts. A multitrophic community, characterized by a shift from oligotrophic to copiotrophic bacteria and the presence of saproxylic arthropod and herbivore insects was found in the cyanobacteria/moss-dominated biocrust, while a more complex biota, characterized by an increased fungal abundance (classes Sordariomycetes, Leotiomycetes, and Dothideomycetes, phylum Ascomycota), associated with highly trophic consumer invertebrates (phyla Arthropoda, Rotifera, Tardigrada), was observed in moss-dominated biocrusts. The class Bdelloidea and the family Hypsibiidae (phyla Rotifera and Tardigrada, respectively) were metazoan indicator taxon in bryophyte carpet, suggesting their potential role in shaping structure and function of this late successional stage. Nitrogen and phosphorus were the main physicochemical limiting factors driving the shift among different crust/biocrust successional stages. Identification and characterization of indicator taxa, biological intra- and inter-kingdom interactions and abiotic factors driving the shift among different crust/biocrust successional stages provide a detailed picture on crust/biocrust dynamics, revealing a strong interconnection among micro- and macrobiota systems. These findings enhance our understanding of biocrust ecosystems in High Arctic, providing valuable insights for their conservation and management in response to environmental shifts due to climate change.


Assuntos
Briófitas , Cianobactérias , Animais , Ecossistema , Solo/química , Biota , Microbiologia do Solo
2.
Microbiol Resour Announc ; 12(10): e0038823, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37754785

RESUMO

The draft genomes of five Naganishia strains were sequenced using MinION and annotated using Funannotate pipeline. Phylogenetic and genomic analyses were performed to provide their genetic relationships, diversity, and potential functional capabilities. This approach will aid in understanding their potential to survive under microgravity and their resilience to extreme environments.

3.
Food Res Int ; 170: 113004, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37316073

RESUMO

The use of non-conventional brewing yeasts as alternative starters is a very promising approach which received increasing attention from worldwide scientists and brewers. Despite the feasible application of non-conventional yeasts in brewing processes, their regulations and safety assessment by the European Food Safety Authority still represent a bottlenecked hampering their commercial release, at least into EU market. Thus, research on yeast physiology, accurate taxonomic species identification and safety concerns associated with the use of non-conventional yeasts in food chains is needed to develop novel healthier and safer beers. Currently, most of the documented brewing applications catalysed by non-conventional yeasts are associated to ascomycetous yeasts, while little is known about analogous uses of basidiomycetous taxa. Therefore, in order to extend the phenotypic diversity of basidiomycetous brewing yeasts the aim of this investigation is to check the fermentation aptitudes of thirteen Mrakia species in relation to their taxonomic position within the genus Mrakia. The volatile profile, ethanol content and sugar consumption were compared with that produced by a commercial starter for low alcohol beers, namely Saccharomycodes ludwigii WSL 17. The phylogeny of Mrakia genus showed three clusters that clearly exhibited different fermentation aptitudes. Members of M. gelida cluster showed a superior aptitude to produce ethanol, higher alcohols, esters and sugars conversion compared to the members of M. cryoconiti and M. aquatica clusters. Among M. gelida cluster, the strain M. blollopis DBVPG 4974 exhibited a medium flocculation profile, a high tolerance to ethanol and to iso-α-acids, and a considerable production of lactic and acetic acids, and glycerol. In addition, an inverse relationship between fermentative performances and incubation temperature is also displayed by this strain. Possible speculations on the association between the cold adaptation exhibited by M. blollopis DBVPG 4974 and the release of ethanol in the intracellular matrix and in the bordering environment are presented.


Assuntos
Aptidão , Basidiomycota , Fermentação , Temperatura , Etanol
4.
FEMS Microbiol Ecol ; 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160346

RESUMO

In the ice-free areas of Victoria Land in continental Antarctica, where the conditions reach the limits for life sustainability, highly adapted and extreme-tolerant microbial communities exploit the last habitable niches inside porous rocks (i.e. cryptoendolithic communities). These guilds host the main standing biomass and principal, if not sole, contributors to environmental/biogeochemical cycles, driving ecosystem processes and functionality in these otherwise dead lands. Although knowledge advances on their composition, ecology, genomic and metabolic features, a large-scale perspective of occurring interactions and interconnections within and between endolithic fungal assemblages is still lacking to date. Unravelling the tight relational network among functional guilds in the Antarctic cryptoendolithic communities may represent a main task. Aiming to fill this knowledge gap, we performed a correlation-network analysis based on amplicon-sequencing data of 74 endolithic microbiomes collected throughout Victoria Land. Endolithic communities' compositional pattern was largely dominated by Lichenized fungi group (83.5%), mainly represented by Lecanorales and Lecideales, followed by Saprotrophs (14.2%) and RIF+BY (2.4%) guilds led by Tremellales and Capnodiales respectively. Our findings highlighted that fungal functional guilds' relational spectrum was dominated by cooperative interactions led by lichenised and black fungi, deeply engaged in community trophic sustain and protection, respectively. On the other hand, a few negative correlations found may help in preserving niche boundaries between microbes living in such strict spatial association.

5.
J Fungi (Basel) ; 9(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37108890

RESUMO

Rock glaciers are relatively common in Antarctic permafrost areas and could be considered postglacial cryogenic landforms. Although the extensive presence of rock glaciers, their chemical-physical and biotic composition remain scarce. Chemical-physical parameters and fungal community (by sequencing the ITS2 rDNA, Illumina MiSeq) parameters of a permafrost core were studied. The permafrost core, reaching a depth of 6.10 m, was divided into five units based on ice content. The five units (U1-U5) of the permafrost core exhibited several significant (p < 0.05) differences in terms of chemical and physical characteristics, and significant (p < 0.05) higher values of Ca, K, Li, Mg, Mn, S, and Sr were found in U5. Yeasts dominated on filamentous fungi in all the units of the permafrost core; additionally, Ascomycota was the prevalent phylum among filamentous forms, while Basidiomycota was the dominant phylum among yeasts. Surprisingly, in U5 the amplicon sequence variants (ASVs) assigned to the yeast genus Glaciozyma represented about two-thirds of the total reads. This result may be considered extremely rare in Antarctic yeast diversity, especially in permafrost habitats. Based on of the chemical-physical composition of the units, the dominance of Glaciozyma in the deepest unit was correlated with the elemental composition of the core.

6.
Environ Res ; 229: 115891, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37059323

RESUMO

Microplastics (MPs) are emerging pollutants whose occurrence is a global problem in natural ecosystems including soil. Among MPs, polyvinyl chloride (PVC) is a well-known polymer with remarkable resistance to degradation, and because its recalcitrant nature serious environmental concerns are created during manufacturing and waste disposal. The effect of PVC (0.021% w/w) on chemical and microbial parameters of an agricultural soil was tested by a microcosm experiment at different incubation times (from 3 to 360 days). Among chemical parameters, soil CO2 emission, fluorescein diacetate (FDA) activity, total organic C (TOC), total N, water extractable organic C (WEOC), water extractable N (WEN) and SUVA254 were considered, while the structure of soil microbial communities was studied at different taxonomic levels (phylum and genus) by sequencing bacterial 16S and fungal ITS2 rDNA (Illumina MiSeq). Although some fluctuations were found, chemical and microbiological parameters exhibited some significant trends. Significant (p < 0.05) variations of soil CO2 emission, FDA hydrolysis, TOC, WEOC and WEN were found in PVC-treated soils over different incubation times. Considering the structure of soil microbial communities, the presence of PVC significantly (p < 0.05) affected the abundances of specific bacterial and fungal taxa: Candidatus_Saccharibacteria, Proteobacteria, Actinobacteria, Acidobacteria and Bacteroides among bacteria, and Basidiomycota, Mortierellomycota and Ascomycota among fungi. After one year of experiment, a reduction of the number and the dimensions of PVC was detected supposing a possible role of microorganisms on PVC degradation. The abundance of both bacterial and fungal taxa at phylum and genus level was also affected by PVC, suggesting that the impact of this polymer could be taxa-dependent.


Assuntos
Microbiota , Microplásticos , Plásticos , Solo , Dióxido de Carbono , Microbiologia do Solo , Bactérias/genética
7.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-37019825

RESUMO

Metschnikowia pulcherrima is an important yeast species that is attracting increased interest thanks to its biotechnological potential, especially in agri-food applications. Phylogenetically related species of the so-called 'pulcherrima clade' were first described and then reclassified in one single species, which makes the identification an intriguing issue. Starting from the whole-genome sequencing of the protechnological strain Metschnikowia sp. DBT012, this study applied comparative genomics to calculate similarity with the M. pulcherrima clade publicly available genomes with the aim to verify if novel single-copy putative phylogenetic markers could be selected, in comparison with the commonly used primary and secondary barcodes. The genome-based bioinformatic analysis allowed the identification of 85 consensus single-copy orthologs, which were reduced to three after split decomposition analysis. However, wet-lab amplification of these three genes in nonsequenced type strains revealed the presence of multiple copies, which made them unsuitable as phylogenetic markers. Finally, average nucleotide identity (ANI) was calculated between strain DBT012 and available genome sequences of the M. pulcherrima clade, although the genome dataset is still rather limited. Presence of multiple copies of phylogenetic markers as well as ANI values were compatible with the recent reclassification of the clade, allowing the identification of strain DBT012 as M. pulcherrima.


Assuntos
Metschnikowia , Metschnikowia/genética , Filogenia , Leveduras/genética , Genômica , Sequenciamento Completo do Genoma
8.
Astrobiology ; 23(4): 395-406, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36812458

RESUMO

Antarctic deserts are among the driest and coldest ecosystems of the planet; there, some microbes survive under these extreme conditions inside porous rocks, forming the so-called endolithic communities. Yet the contribution of distinct rock traits to support complex microbial assemblies remains poorly determined. Here, we combined an extensive Antarctic rock survey with rock microbiome sequencing and ecological networks and found that contrasting combinations of microclimatic and rock traits such as thermal inertia, porosity, iron concentration, and quartz cement can help explain the multiple complex microbial assemblies found in Antarctic rocks. Our work highlights the pivotal role of rocky substrate heterogeneity in sustaining contrasting groups of microorganisms, which is essential to understand life at the edge on Earth and for the search for life on other rocky planets such as Mars.


Assuntos
Ecossistema , Exobiologia , Planetas , Planeta Terra , Regiões Antárticas
9.
Front Microbiol ; 13: 1026102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36425045

RESUMO

Microorganisms including yeasts are responsible for mineralization of organic matter in cold regions, and their characterization is critical to elucidate the ecology of such environments on Earth. Strategies developed by yeasts to survive in cold environments have been increasingly studied in the last years and applied to different biotechnological applications, but their knowledge is still limited. Microbial adaptations to cold include the synthesis of cryoprotective compounds, as well as the presence of a high number of genes encoding the synthesis of proteins/enzymes characterized by a reduced proline content and highly flexible and large catalytic active sites. This study is a comparative genomic study on the adaptations of yeasts isolated from the Italian Alps, considering their growth kinetics. The optimal temperature for growth (OTG), growth rate (Gr), and draft genome sizes considerably varied (OTG, 10°C-20°C; Gr, 0.071-0.0726; genomes, 20.7-21.5 Mpb; %GC, 50.9-61.5). A direct relationship was observed between calculated protein flexibilities and OTG, but not for Gr. Putative genes encoding for cold stress response were found, as well as high numbers of genes encoding for general, oxidative, and osmotic stresses. The cold response genes found in the studied yeasts play roles in cell membrane adaptation, compatible solute accumulation, RNA structure changes, and protein folding, i.e., dihydrolipoamide dehydrogenase, glycogen synthase, omega-6 fatty acid, stearoyl-CoA desaturase, ATP-dependent RNA helicase, and elongation of very-long-chain fatty acids. A redundancy for several putative genes was found, higher for P-loop containing nucleoside triphosphate hydrolase, alpha/beta hydrolase, armadillo repeat-containing proteins, and the major facilitator superfamily protein. Hundreds of thousands of small open reading frames (SmORFs) were found in all studied yeasts, especially in Phenoliferia glacialis. Gene clusters encoding for the synthesis of secondary metabolites such as terpene, non-ribosomal peptide, and type III polyketide were predicted in four, three, and two studied yeasts, respectively.

10.
Int J Syst Evol Microbiol ; 72(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36201346

RESUMO

Six strains of black meristematic fungi were isolated from Antarctic soils, gasoline car tanks and from the marine alga Flabellia petiolata. These fungi were characterized by morphological, physiological and phylogenetic analyses. According to the maximum-likelihood analysis reconstructed with ITS and LSU sequences, these strains belonged to the genus Knufia. Knufia obscura sp. nov. (holotype CBS 148926) and Knufia victoriae sp. nov. (holotype CBS 149015) are proposed as two novel species and descriptions of their morphological, physiological and phylogenetic features are presented. Based on the maximum-likelihood analyses, K. obscura was closely related to Knufia hypolithi (99 % bootstrap support), while K. victoriae clustered in the clade of Knufia cryptophialidica and Knufia perfecta (93 % bootstrap support). Knufia victoriae, recorded in Antarctic soil samples, had a psychrophilic behaviour, with optimal growth between 10 and 15 °C and no growth recorded at 20 °C. Knufia obscura, from a gasoline car tank and algae, displayed optimal growth between 20 and 25 °C and was more tolerant to salinity than K. victoriae.


Assuntos
Ácidos Graxos , Gasolina , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ambientes Extremos , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo
11.
Environ Microbiol ; 24(9): 4178-4192, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35691701

RESUMO

The impact of global warming on biological communities colonizing European alpine ecosystems was recently studied. Hexagonal open top chambers (OTCs) were used for simulating a short-term in situ warming (estimated around 1°C) in some alpine soils to predict the impact of ongoing climate change on resident microbial communities. Total microbial DNA was extracted from soils collected either inside or outside the OTCs over 3 years of study. Bacterial and fungal rRNA copies were quantified by qPCR. Metabarcoding sequencing of taxonomy target genes was performed (Illumina MiSeq) and processed by bioinformatic tools. Alpha- and beta-diversity were used to evaluate the structure of bacterial and fungal communities. qPCR suggests that, although fluctuations have been observed between soils collected either inside and outside the OTCs, the simulated warming induced a significant (p < 0.05) shift only for bacterial abundance. Likewise, significant (p < 0.05) changes in bacterial community structure were detected in soils collected inside the OTCs, with a clear increase of oligotrophic taxa. On the contrary, fungal diversity of soils collected either inside and outside the OTCs did not exhibit significant (p < 0.05) differences, suggesting that the temperature increase in OTCs compared to ambient conditions was not sufficient to change fungal communities.


Assuntos
Microbiota , Micobioma , Bactérias/genética , Mudança Climática , Microbiota/genética , Solo/química , Microbiologia do Solo
12.
Yeast ; 39(1-2): 4-24, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35146791

RESUMO

Yeasts are ubiquitous in temperate forests. While this broad habitat is well-defined, the yeasts inhabiting it and their life cycles, niches, and contributions to ecosystem functioning are less understood. Yeasts are present on nearly all sampled substrates in temperate forests worldwide. They associate with soils, macroorganisms, and other habitats and no doubt contribute to broader ecosystem-wide processes. Researchers have gathered information leading to hypotheses about yeasts' niches and their life cycles based on physiological observations in the laboratory as well as genomic analyses, but the challenge remains to test these hypotheses in the forests themselves. Here, we summarize the habitat and global patterns of yeast diversity, give some information on a handful of well-studied temperate forest yeast genera, discuss the various strategies to isolate forest yeasts, and explain temperate forest yeasts' contributions to biotechnology. We close with a summary of the many future directions and outstanding questions facing researchers in temperate forest yeast ecology. Yeasts present an exciting opportunity to better understand the hidden world of microbial ecology in this threatened and global habitat.


Assuntos
Ecossistema , Árvores , Biodiversidade , Florestas , Leveduras/genética
13.
IMA Fungus ; 12(1): 18, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256869

RESUMO

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.

14.
Biology (Basel) ; 10(4)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920495

RESUMO

In Victoria Land, Antarctica, ice-free areas are restricted to coastal regions and dominate the landscape of the McMurdo Dry Valleys. These two environments are subjected to different pressures that determine the establishment of highly adapted fungal communities. Within the kingdom of fungi, filamentous, yeasts and meristematic/microcolonial growth forms on one side and different lifestyles on the other side may be considered adaptive strategies of particular interest in the frame of Antarctic constraints. In this optic, soil fungal communities from both coastal and Dry Valleys sites, already characterized thorough ITS1 metabarcoding sequencing, have been compared to determine the different distribution of phyla, growth forms, and lifestyles. Though we did not find significant differences in the richness between the two environments, the communities were highly differentiated and Dry Valleys sites had a higher evenness compared to coastal ones. Additionally, the distribution of different growth forms and lifestyles were well differentiated, and their diversity and composition were likely influenced by soil abiotic parameters, among which soil granulometry, pH, P, and C contents were the potential main determinants.

15.
Int J Syst Evol Microbiol ; 70(8): 4704-4713, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32697190

RESUMO

Five yeast strains were isolated from soil and sediments collected from Alps and Apennines glaciers during sampling campaigns carried out in summer 2007 and 2017, respectively. Based on morphological and physiological tests and on phylogenetic analyses reconstructed with ITS and D1/D2 sequences, the five strains were considered to belong to two related but hitherto unknown species within the genus Mrakia, in an intermediate position between Mrakia cryoconiti and Mrakia arctica. The names Mrakia stelviica (holotype DBVPG 10734T) and Mrakia montana (holotype DBVPG 10736T) are proposed for the two novel species and a detailed description of their morphological, physiological and phylogenetic features are presented. Both species fermented glucose, sucrose and trehalose, which is an uncommon feature in basidiomycetous yeasts, and showed septate hyphae with teliospore formation.


Assuntos
Basidiomycota/classificação , Camada de Gelo/microbiologia , Filogenia , Animais , Basidiomycota/isolamento & purificação , DNA Fúngico/genética , Itália , Técnicas de Tipagem Micológica , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
16.
Microorganisms ; 8(6)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32585947

RESUMO

The endolithic niche represents an ultimate refuge to microorganisms in the Mars-like environment of the Antarctic desert. In an era of rapid global change and desertification, the interest in these border ecosystems is increasing due to speculation on how they maintain balance and functionality at the dry limits of life. To assure a reliable estimation of microbial diversity, proper sampling must be planned in order to avoid the necessity of re-sampling as reaching these remote locations is risky and requires tremendous logistical and economical efforts. In this study, we seek to determine the minimum number of samples for uncovering comprehensive bacterial and fungal diversity, comparing communities in strict vicinity to each other. We selected three different locations of the Victoria Land (Continental Antarctica) at different altitudes and showing sandstone outcrops of a diverse nature and origin-Battleship promontory (834 m above sea level (a.s.l.), Southern VL), Trio Nunatak (1,470 m a.s.l., Northern VL) and Mt New Zealand (3,100 m a.s.l., Northern VL). Overall, we found that a wider sampling would be required to capture the whole amplitude of microbial diversity, particularly in Northern VL. We concluded that the inhomogeneity of the rock matrix and the stronger environmental pressure at higher altitudes may force the communities to a higher local diversification.

17.
Environ Microbiol ; 22(8): 3463-3477, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32510727

RESUMO

A perennially frozen lake at Boulder Clay site (Victoria Land, Antarctica), characterized by the presence of frost mounds, have been selected as an in situ model for ecological studies. Different samples of permafrost, glacier ice and brines have been studied as a unique habitat system. An additional sample of brines (collected in another frozen lake close to the previous one) was also considered. Alpha- and beta-diversity of fungal communities showed both intra- and inter-cores significant (p < 0.05) differences, which suggest the presence of interconnection among the habitats. Therefore, the layers of frost mound and the deep glacier could be interconnected while the brines could probably be considered as an open habitat system not interconnected with each other. Moreover, the absence of similarity between the lake ice and the underlying permafrost suggested that the lake is perennially frozen based. The predominance of positive significant (p < 0.05) co-occurrences among some fungal taxa allowed to postulate the existence of an ecological equilibrium in the habitats systems. The positive significant (p < 0.05) correlation between salt concentration, total organic carbon and pH, and some fungal taxa suggests that a few abiotic parameters could drive fungal diversity inside these ecological niches.


Assuntos
Fungos/classificação , Camada de Gelo/microbiologia , Pergelissolo/microbiologia , Regiões Antárticas , Argila , Ecossistema , Fungos/genética , Camada de Gelo/química , Lagos/química , Lagos/microbiologia , Micobioma , Compostos Orgânicos/análise , Pergelissolo/química , Salinidade , Sais/análise
18.
FEMS Microbiol Lett ; 367(5)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32149346

RESUMO

The European Culture Collections' Organisation presents two new model documents for Material Deposit Agreement (MDA) and Material Transfer Agreement (MTA) designed to enable microbial culture collection leaders to draft appropriate agreement documents for, respectively, deposit and supply of materials from a public collection. These tools provide guidance to collections seeking to draft an MDA and MTA, and are available in open access to be used, modified, and shared. The MDA model consists of a set of core fields typically included in a 'deposit form' to collect relevant information to facilitate assessment of the status of the material under access and benefit sharing (ABS) legislation. It also includes a set of exemplary clauses to be included in 'terms and conditions of use' for culture collection management and third parties. The MTA model addresses key issues including intellectual property rights, quality, safety, security and traceability. Reference is made to other important tools such as best practices and code of conduct related to ABS issues. Besides public collections, the MDA and MTA model documents can also be useful for individual researchers and microbial laboratories that collect or receive microbial cultures, keep a working collection, and wish to share their material with others.


Assuntos
Biodiversidade , Pesquisa Biomédica/legislação & jurisprudência , Manejo de Espécimes , Transferência de Tecnologia , Europa (Continente) , Humanos
19.
Microorganisms ; 8(2)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093408

RESUMO

The involvement of DNA methylation in the response to cold stress of two different yeast species (Naganishia antarctica, psychrophilic, and Naganishia albida, psychrotolerant), exhibiting different temperature aptitudes, has been studied. Consecutive incubations at respective optimum temperatures, at 4 °C (cold stress) and at optimum temperatures again, were performed. After Methylation Sensitive Amplified Polymorphism (MSAP) fingerprints a total of 550 and 423 clear and reproducible fragments were amplified from N. antarctica and N. albida strains, respectively. The two Naganishia strains showed a different response in terms of level of DNA methylation during cold stress and recovery from cold stress. The percentage of total methylated fragments in psychrophilic N. antarctica did not show any significant change. On the contrary, the methylation of psychrotolerant N. albida exhibited a nonsignificant increase during the incubation at 4 °C and continued during the recovery step, showing a significant difference if compared with control condition, resembling an uncontrolled response to cold stress. A total of 12 polymorphic fragments were selected, cloned, and sequenced. Four fragments were associated to genes encoding for elongation factor G and for chitin synthase export chaperon. To the best of our knowledge, this is the first study on DNA methylation in the response to cold stress carried out by comparing a psychrophilic and a psychrotolerant yeast species.

20.
Microorganisms ; 7(12)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842279

RESUMO

Microorganisms represent most of the biodiversity of living organisms in every ecological habitat. They have profound effects on the functioning of any ecosystem, and therefore on the health of our planet and of human beings. Moreover, microorganisms are the main protagonists in food, medical and biotech industries, and have several environmental applications. Accordingly, the characterization and preservation of microbial biodiversity are essential not only for the maintenance of natural ecosystems but also for research purposes and biotechnological exploitation. In this context, culture collections (CCs) and microbial biological resource centres (mBRCs) are crucial for the safeguarding and circulation of biological resources, as well as for the progress of life sciences. This review deals with the expertise and services of CCs, in particular concerning preservation and characterization of microbial resources, by pointing to the advanced approaches applied to investigate a huge reservoir of microorganisms. Data sharing and web services as well as the tight interconnection between CCs and the biotechnological industry are highlighted. In addition, guidelines and regulations related to quality management systems (QMSs), biosafety and biosecurity issues are discussed according to the perspectives of CCs and mBRCs.

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