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1.
New Phytol ; 235(3): 1246-1259, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35460285

RESUMO

During our initial phylogenetic study of the monocot genus Erythronium (Liliaceae), we observed peculiar eudicot-type internal transcribed spacer (ITS) sequences in a dataset derived from genomic DNA of Erythronium dens-canis. This raised the possibility of horizontal transfer of a eudicot alien ribosomal DNA (rDNA) into the Erythronium genome. In this work we aimed to support this hypothesis by carrying out genomic, molecular, and cytogenetic analyses. Genome skimming coupled by PacBio HiFi sequencing of a bacterial artificial chromosome clone derived from flow-sorted nuclei was used to characterise the alien 45S rDNA. Integration of alien rDNA in the recipient genome was further proved by Southern blotting and fluorescence in situ hybridization using specific probes. Alien rDNA, nested among Potentilla species in phylogenetic analysis, likely entered the Erythronium lineage in the common ancestor of E. dens-canis and E. caucasicum. Transferred eudicot-type rDNA preserved its tandemly arrayed feature on a single chromosome and was found to be transcribed in the monocot host, albeit much less efficiently than the native counterpart. This study adds a new example to the rarely documented nuclear-to-nuclear jumps of DNA between eudicots and monocots while holding the scientific community continually in suspense about the mode of DNA transfer.


Assuntos
Liliaceae , Potentilla , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Hibridização in Situ Fluorescente , Filogenia , Potentilla/genética
2.
Mol Ecol ; 24(1): 235-48, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25443313

RESUMO

Micro-organisms associated with plants and animals affect host fitness, shape community structure and influence ecosystem properties. Climate change is expected to influence microbial communities, but their reactions are not well understood. Host-associated micro-organisms are influenced by the climate reactions of their hosts, which may undergo range shifts due to climatic niche tracking, or may be actively relocated to mitigate the effects of climate change. We used a common-garden experiment and rDNA metabarcoding to examine the effect of host relocation and high-latitude warming on the complex fungal endophytic microbiome associated with leaves of an ecologically dominant boreal forest tree (Populus balsamifera L.). We also considered the potential effects of poplar genetic identity in defining the reactions of the microbiome to the treatments. The relocation of hosts to the north increased the diversity of the microbiome and influenced its structure, with results indicating enemy release from plausible pathogens. High-latitude warming decreased microbiome diversity in comparison with natural northern conditions. The warming also caused structural changes, which made the fungal communities distinct in comparison with both low-latitude and high-latitude natural communities, and increased the abundance of plausible pathogens. The reactions of the microbiome to relocation and warming were strongly dependent on host genetic identity. This suggests that climate change effects on host-microbiome systems may be mediated by the interaction of environmental factors and the population genetic processes of the hosts.


Assuntos
Fungos/classificação , Aquecimento Global , Microbiota , Populus/microbiologia , Biodiversidade , Canadá , Endófitos/classificação , Modelos Lineares , Folhas de Planta/microbiologia , Árvores/microbiologia
3.
J Plant Res ; 128(5): 721-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26040419

RESUMO

Four Erythronium species have been traditionally recognised within Eurasia based on their disjunct distributions and the slight morphological divergence between them: E. dens-canis, E. caucasicum, E. sibiricum and E. japonicum. The range of E. sibiricum includes adjacent parts of southern Siberia, Kazakhstan, China and Mongolia in the Altai-Sayan mountain region. Despite several recently proposed taxa within the range of E. sibiricum (E. sajanense, E. sibiricum subsp. altaicum, E. sibiricum subsp. sulevii), this species has never been tested for genetic subdivisions. We here used nucleotide sequence variation in one nuclear (internal transcribed spacer) and two plastid (rpl32-trnL, rps15-ycf1) regions to test for genetic divisions within Siberian Erythronium and, in particular, to examine the phylogenetic position of E. sajanense. The plastid phylogeny revealed a basal polytomy among E. japonicum, E. sibiricum populations pertaining to E. sajanense and a third strongly supported lineage that includes E. dens-canis, E. caucasicum and the remainder of E. sibiricum, thus rendering Siberian Erythronium non-monophyletic. The nuclear topology agrees with the plastid one in recovering E. sajanense as a distinct lineage that is weakly supported as sister to E. japonicum. Topological incongruences exist between the plastid and nuclear phylogenies but these do not affect the taxonomic recognition of E. sajanense (endemic to the Western Sayan Mts.). This species is morphologically distinguishable on the basis of its subulate stamen filaments. Whereas nuclear phylogeny failed to resolve any genetic grouping within E. sibiricum s. str., plastid data recovered a deep (possibly phylogeographically meaningful) lineage from samples referred to as E. sibiricum subsp. altaicum.


Assuntos
DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Variação Genética , Liliaceae/genética , Dados de Sequência Molecular , Filogenia , Plastídeos/genética , Análise de Sequência de DNA , Sibéria
4.
MethodsX ; 12: 102671, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38577407

RESUMO

Surfactants have a significant role in everyday life and various industries. Their amphipathic nature significantly influences their properties, functions, and applicability. The ratio of water and oil solubility is characterized by the HLB value (hydrophilic-lipophilic balance) or the closely related water number. A determination of the water number of surfactants represents the amount of water that a surfactant can incorporate into a microemulsion. The results of measuring the water number provide information about the hydrophilic properties of the surfactant in question. Understanding the water number helps determine the applicability of surfactants. From the water number of surfactants, conclusions can be drawn about the HLB value of the particular surfactant, providing further insights into its properties. Although a well-established method for determining water number has long been available, it has been revealed that many of the auxiliary substances and chemicals used in this process have severe health-damaging effects, leading to their discontinuation in routine laboratory use. Our goal was to find a solvent combination that would be suitable for the water number determination method. Additionally, we aimed to investigate solvents that are environmentally and human-biologically less harmful, easily and affordably obtainable.•The study presents a method for determining the water number of surfactants.•The method is straightforward to execute and free from harmful solvents.•By improving the method, we enhanced the reliability of the examination.

5.
FEMS Microbiol Lett ; 363(14)2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27279625

RESUMO

Heavy metals are dense chemicals with dual biological role as micronutrients and intoxicants. A few hypersaline environmental systems are naturally enriched with heavy metals, while most metal-contaminated sites are a consequence of human activities. Numerous halotolerant and moderately halophilic Bacteria possess metal tolerance, whereas a few archaeal counterparts share similar features. The main mechanisms underlying heavy metal resistance in halophilic Bacteria and Archaea include extracellular metal sequestration by biopolymers, metal efflux mediated by specific transporters and enzymatic detoxification. Biotransformation of metals by halophiles has implications both for trace metal turnover in natural saline ecosystems and for development of novel bioremediation strategies.


Assuntos
Adaptação Biológica , Archaea/fisiologia , Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos , Metais Pesados/metabolismo , Archaea/classificação , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Biodegradação Ambiental , Transporte Biológico , Membrana Celular/metabolismo , Inativação Metabólica , Metais Pesados/farmacologia , Células Procarióticas/fisiologia , Salinidade
6.
Waste Manag ; 38: 65-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25648118

RESUMO

In our work processing conditions and mechanical properties of waste polyethylene (PE)/crumb rubber (CR) blends have been improved by new types of compatibilizing additives synthesized from experimental olefin-maleic-anhydride copolymers at our laboratory. Compatibilizing additives have been introduced into the PE/CR blends in 0.2 wt% while CR concentration has been varied between 10 and 50 wt%. For comparison of the effects commercially available MA-g-PO type compatibilizing additives have also been applied. Tensile and Charpy impact tests of the compression moulded samples have been carried out. Several experimental additives have enhanced properties of the PE/CR blends either from the point of view of tensile or Charpy impact strength while commercial additives have had improving effects only on one of the abovementioned mechanical properties but not for both of them simultaneously. Since good mechanical properties could be achieved by our experimental compatibilizers good adhesion in the waste PE/CR samples have been considered and was proven by SEM graphs either.


Assuntos
Alcenos/química , Anidridos/química , Maleatos/química , Polietilenos/química , Reciclagem/métodos , Borracha/química , Gerenciamento de Resíduos/métodos , Polímeros/química
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(9): 1995-2007, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12788453

RESUMO

1D and 2D 1H and 13C NMR spectra of the assumed [MoO(4)(TEA)](2-) complex recorded in DMSO at variable temperatures clearly indicate one free and two bound hydroxyethyl arms. The free arm of the ligand readily exchanges with the two metal-bound arms. Under such conditions the triethanolamine (TEA) acts as a bidentate ligand. The presence of water accelerates the exchange, which at higher water content involves the free ligand too. In organic solvents the binding strength of the hydroxo groups to the molybdenum is weaker than that of the water molecules. A plausible structure is confirmed by 14N, 17O and 95Mo measurements and an exchange mechanism based on the existence of an eight-membered relatively rigid chelate ring is suggested.


Assuntos
Etanolaminas/química , Molibdênio/química , Espectroscopia de Ressonância Magnética
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