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1.
Macromol Rapid Commun ; : e2400196, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830612

RESUMO

The utilization of two-component systems comprising camphorquinone (CQ) and aromatic amines has become prevalent in the photopolymerization. However, there are still concerns about the safety of this CQ/amine system, mainly because of the toxicity associated with the leaching of aromatic amines. In light of these concerns, this study aims to develop novel coinitiator combinations featuring CQ and amines which cannot be leached out of materials, enabling free radical polymerization of representative dentalmethacrylate resins under blue light irradiation. This approach involves the initial design and analysis of hydrogen donors with low C─H bond dissociation energy through molecular modeling. Subsequently, copolymerizable methacrylate functional groups are incorporated via chemical modification, allowing it to act as both coinitiator and copolymerization monomer to achieve low migrationand leachability properties. This work presents, for the first time, the synthesis of the innovative coinitiator and compares its performance with the benchmark CQ/ethyl-4-dimethylaminobenzoate (EDB)-based photoinitiation system (PIS). The results demonstrate the effectiveness of the newly proposed PIS. Finally, an in-depth investigation is conducted into the reaction mechanism associated with this PIS through molecular orbital calculations and electron spin resonance studies.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38768969

RESUMO

(Adaptive) radiations have attracted evolutionary biologists for a long time as ideal model systems to study patterns and processes of often rapid speciation. However, whereas a wealth of (sometimes already genome-scale) data is available for host radiations, very few studies target the patterns of diversification in their symbionts, even though they would be excellent models to study symbiont speciation. Our review summarizes what little is known about general patterns of symbiont diversification in often iconic adaptive host radiations and to what extent these patterns are dependent on the evolutionary trajectories of their hosts. We identify research gaps that need to be addressed in the future and discuss the potential of approaches not yet typically used in these study systems, such as epidemiological disease modeling and new omics technologies, for significantly advancing our understanding of these complex eco-evolutionary relationships.

3.
J Fish Dis ; 47(5): e13918, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38235825

RESUMO

Detection of intestinal parasites in fish typically requires autopsy, resulting in the sacrifice of the fish. Here, we describe a non-lethal method for detecting the tapeworm Eubothrium crassum in fish using anal swabs and real-time PCR detection. Two assays were developed to detect cytochrome oxidase I (COI) mitochondrial DNA and 18S ribosomal DNA sequences of E. crassum, respectively. The assays were tested on swab samples from confirmed pathogen free Atlantic salmon (Salmo salar L.) and on samples from farmed Atlantic salmon, where the presence and intensity of parasites had been established through autopsy. The COI assay was shown to be specific to E. crassum, while the 18S assay also amplified the closely related E. salvelini, a species infecting Arctic charr (Salvelinus alpinus L.) in freshwater. The COI assay detected E. crassum in all field samples regardless of parasite load while the 18S assay failed to detect the parasite in two samples. The results thus demonstrates that this non-lethal approach can effectively detect E. crassum and can be a valuable tool in assessing the prevalence of infection in farmed salmon, aiding in treatment decisions and evaluating treatment effectiveness.


Assuntos
Cestoides , Infecções por Cestoides , Doenças dos Peixes , Salmo salar , Animais , Salmo salar/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/parasitologia , Cestoides/genética , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/veterinária , Infecções por Cestoides/parasitologia , Truta/parasitologia
4.
J Am Chem Soc ; 145(49): 26688-26698, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38048399

RESUMO

The bicyclic 1,2-substituted, 1,3-diene monomer nopadiene (1R,5S)-2-ethenyl-6,6-dimethylbicyclo[3.1.1]hept-2-ene was successfully polymerized by anionic and catalytic polymerization. Nopadiene is produced either through a facile one-step synthesis from myrtenal via Wittig-olefination or via a scalable two-step reaction from nopol (10-hydroxymethylene-2-pinene). Both terpenoids originate from the renewable ß-pinene. The living anionic polymerization of nopadiene in apolar and polar solvents at 25 °C using organolithium initiators resulted in homopolymers with well-controlled molar masses in the range of 5.6-103.4 kg·mol-1 (SEC, PS calibration) and low dispersities (D) between 1.06 and 1.18. By means of catalytic polymerization with Me4CpSi(Me)2NtBuTiCl2 and (Flu)(Pyr)CH2Lu(CH2TMS)2(THF), the 1,4 and 3,4- microstructures of nopadiene are accessible in excellent selectivity. In pronounced contrast to other 1,3-dienes, the rigid polymers of the sterically demanding nopadiene showed an elevated glass temperature, Tg,∞ = 160 °C (in the limit of very high molar mass, Mn). ABA triblock copolymers with a central polymyrcene block and myrcene content of 60-75 mol %, with molar masses of 100-200 kg/mol were prepared by living anionic polymerization of the pinene-derivable monomers nopadiene and myrcene. This diene copolymerization resulted in thermoplastic elastomers displaying nanophase separation at different molar ratios (DSC, SAXS) and an upper service temperature about 30 K higher than that for traditional petroleum-derived styrenic thermoplastic elastomers due to the high glass temperature of polynopadiene. The materials showed good thermal stability at elevated temperatures under nitrogen (TGA), promising tensile strength and ultimate elongation of up to 1600%.

5.
Parasite ; 30: 27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37409878

RESUMO

Polystomatidae is a monogenean family whose representatives infect mainly (semi)-aquatic tetrapods. Species of Sphyranura Wright, 1879 exhibit ectoparasitism on salamander hosts, with molecular work supporting their inclusion within Polystomatidae, at an early diverging, yet unresolved, position in the clade of otherwise endoparasitic polystomatid parasites of batrachian hosts. Records of representatives of Sphyranura are scarce with genetic data only available for S. oligorchis Alvey, 1933. Based on detailed morphological examination and comparison with type material, we identified worms belonging to Sphyranura infecting Oklahoma salamander (Eurycea tynerensis) as S. euryceae Hughes & Moore, 1943. Along with an amended diagnosis of Sphyranura, we provide the first molecular data for S. euryceae in the form of a mitochondrial genome and nuclear (18S, 28S rRNA) markers. Close morphological similarity between the two species of Sphyranura is reflected in low genetic divergence. Mitochondrial level comparison reveals instances of tRNA gene rearrangements in polystomatids. Although the phylogenetic reconstruction supports Sphyranura as early branching in the lineage of polystomatid monogeneans infecting batrachians, certain nodes remain unresolved.


Title: Diagnostic modifié, génome mitochondrial et position phylogénétique de Sphyranura euryceae (Neodermata, Monogenea, Polystomatidae), un parasite de la salamandre de l'Oklahoma. Abstract: Les Polystomatidae sont une famille de monogènes dont les représentants infectent principalement les tétrapodes (semi)-aquatiques. Les espèces de Sphyranura Wright, 1879 présentent un ectoparasitisme sur les hôtes salamandres, et des travaux moléculaires soutiennent leur inclusion dans les Polystomatidae, à une position divergente précoce mais non résolue dans le clade des Polystomatidae endoparasites d'hôtes batraciens. Les signalements des représentants de Sphyranura sont rares et les données génétiques ne sont disponibles que pour S. oligorchis Alvey, 1933. Sur la base d'un examen morphologique détaillé et d'une comparaison avec le matériel type, nous avons identifié les vers appartenant à Sphyranura infectant la salamandre de l'Oklahoma (Eurycea tynerensis) comme S. euryceae Hughes & Moore, 1943. Parallèlement à un diagnostic modifié de Sphyranura, nous fournissons les premières données moléculaires pour S. euryceae sous la forme d'un génome mitochondrial et de marqueurs nucléaires (ARNr 18S, 28S). La similitude morphologique étroite entre les deux espèces de Sphyranura se traduit par une faible divergence génétique. La comparaison au niveau mitochondrial révèle des cas de réarrangements des gènes des ARNt chez les Polystomatidae. Bien que la reconstruction phylogénétique soutienne Sphyranura comme un rameau précoce dans la lignée des monogènes Polystomatidae infectant les batraciens, certains nœuds restent non résolus.


Assuntos
Genoma Mitocondrial , Parasitos , Trematódeos , Animais , Filogenia , Parasitos/genética , Urodelos/genética , Oklahoma
6.
BMC Genomics ; 24(1): 363, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37380941

RESUMO

BACKGROUND: Monogenea (Platyhelminthes, Neodermata) are the most species-rich class within the Neodermata superclass of primarily fish parasites. Despite their economic and ecological importance, monogenean research tends to focus on their morphological, phylogenetic, and population characteristics, while comprehensive omics analyses aimed at describing functionally important molecules are few and far between. We present a molecular characterisation of monogenean representative Eudiplozoon nipponicum, an obligate haematophagous parasite infecting the gills of the common carp. We report its nuclear and mitochondrial genomes, present a functional annotation of protein molecules relevant to the molecular and biochemical aspect of physiological processes involved in interactions with the fish hosts, and re-examinate the taxonomic position of Eudiplozoon species within the Diplozoidae family. RESULTS: We have generated 50.81 Gbp of raw sequencing data (Illumina and Oxford Nanopore reads), bioinformatically processed, and de novo assembled them into a genome draft 0.94 Gbp long, consisting of 21,044 contigs (N50 = 87 kbp). The final assembly represents 57% of the estimated total genome size (~ 1.64 Gbp), whereby repetitive and low-complexity regions account for ~ 64% of the assembled length. In total, 36,626 predicted genes encode 33,031 proteins and homology-based annotation of protein-coding genes (PCGs) and proteins characterises 14,785 (44.76%) molecules. We have detected significant representation of functional proteins and known molecular functions. The numbers of peptidases and inhibitors (579 proteins), characterised GO terms (16,016 unique assigned GO terms), and identified KEGG Orthology (4,315 proteins) acting in 378 KEGG pathways demonstrate the variety of mechanisms by which the parasite interacts with hosts on a macromolecular level (immunomodulation, feeding, and development). Comparison between the newly assembled E. nipponicum mitochondrial genome (length of 17,038 bp) and other diplozoid monogeneans confirms the existence of two distinct Eudiplozoon species infecting different fish hosts: Cyprinus carpio and Carassius spp. CONCLUSIONS: Although the amount of sequencing data and characterised molecules of monogenean parasites has recently increased, a better insight into their molecular biology is needed. The E. nipponicum nuclear genome presented here, currently the largest described genome of any monogenean parasite, represents a milestone in the study of monogeneans and their molecules but further omics research is needed to understand these parasites' biological nature.


Assuntos
Carpas , Parasitos , Trematódeos , Animais , Carpas/genética , Filogenia , Genômica
7.
Angew Chem Int Ed Engl ; 62(28): e202302907, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37186346

RESUMO

We report the first anionic polymerization of 1-vinylcyclohexene (VCH). This structure may be considered as an intermediate between dienes and styrene. The polymerization of this cyclic 1,2-disubstituted 1,3-diene proceeded quantitatively in cyclohexane at 25 °C with sec-butyllithium as an initiator. The obtained polymers have well-controlled molecular weights in the range of 5 to 142 kg mol-1 , controlled by the molar ratio of monomer and initiator, with narrow molecular weight distributions (D<1.07-1.20). In situ 1 H NMR kinetic characterization revealed a weak gradient structure for the copolymers of styrene and VCH, (rSty =2.55, rVCH =0.39). P(VCH) obtained in cyclohexane with sec-BuLi as an initiator showed both 1,4- and 3,4-incorporation mode (ratio: 64 : 36). It was demonstrated that the microstructure of the resulting P(VCH) can be altered by the addition of a modifier (THF), resulting in increasing 3,4-microstructure (up to 78 %) and elevated glass-transition temperature up to 89 °C. Thus, the monomer VCH polymerizes carbanionically like a diene, however leading to rigid polymers with high glass transition temperature, which provides interesting options for combination with other dienes to well-defined polymer architectures and materials.

8.
Phys Chem Chem Phys ; 24(12): 7493-7504, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35275154

RESUMO

In this work, a Fe/HBEA zeolite (Si/Al: 12.5), representing an effective catalyst for the NH3-SCR process, was physico-chemically characterized and investigated regarding the kinetics of the adsorption and desorption of NH3. The sample was evaluated by N2 physisorption, 57Fe Möessbauer and DRUV-Vis spectroscopy, while the kinetics was investigated by temperature-programmed desorption of NH3 (TPD) including different adsorption temperatures. It was shown that the NH3 chemisorption results in weakly and strongly bonded molecular ammonia as well as ammonium species. A kinetic mean field model was developed implying two different types of adsorbates reflecting low (ca. 200 °C). Kinetic parameters and surface coverages were obtained from numeric fits of the TPD curves, whereas pre-exponential factors of adsorption were deduced from the kinetic gas theory. As a result, the activation energy for the NHx adsorbate decomposition in the low temperature regime, which is assigned to single and double bonded ammonium species was determined to be 106 kJ mol-1. The NH3 desorption at higher temperatures referred to an activation energy of 133 kJ mol-1 predominately related to NH3 coordinated to Lewis acid surface sites and to some extent to stabilized NH4+ species. For validation of the kinetic model, experiments were simulated including NH3 adsorption at different temperatures, subsequent flushing with N2 and final TPD. Additionally, the consistency of the activation energies with the thermodynamic data was checked using differential scanning calorimetry and a van't Hoff approach.

9.
Genes (Basel) ; 13(2)2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35205277

RESUMO

Brassica oleracea is a vegetable crop with an amazing morphological diversity. Among the various crops derived from B. oleracea, kale has been in the spotlight globally due to its various health-benefitting compounds and many different varieties. Knowledge of the existing genetic diversity is essential for the improved breeding of kale. Here, we analyze the interrelationships, population structures, and genetic diversity of 72 kale and cabbage varieties by extending our previous diversity analysis and evaluating the use of summed potential lengths of shared haplotypes (SPLoSH) as a new method for such analyses. To this end, we made use of the high-density Brassica 60K SNP array, analyzed SNPs included in an available Brassica genetic map, and used these resources to generate and evaluate the information from SPLoSH data. With our results we could consistently differentiate four groups of kale across all analyses: the curly kale varieties, Italian, American, and Russian varieties, as well as wild and cultivated types. The best results were achieved by using SPLoSH information, thus validating the use of this information in improving analyses of interrelations in kale. In conclusion, our definition of kale includes the curly varieties as the kales in a strict sense, regardless of their origin. These results contribute to a better understanding of the huge diversity of kale and its interrelations.


Assuntos
Brassica , Brassica/genética , Produtos Agrícolas/genética , Itália , Melhoramento Vegetal , Federação Russa
10.
J Biotechnol ; 341: 43-50, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34400238

RESUMO

Collaborative research is common practice in modern life sciences. For most projects several researchers from multiple universities collaborate on a specific topic. Frequently, these research projects produce a wealth of data that requires central and secure storage, which should also allow for easy sharing among project participants. Only under best circumstances, this comes with minimal technical overhead for the researchers. Moreover, the need for data to be analyzed in a reproducible way often poses a challenge for researchers without a data science background and thus represents an overly time-consuming process. Here, we report on the integration of CyVerse Austria (CAT), a new cyberinfrastructure for a local community of life science researchers, and provide two examples how it can be used to facilitate FAIR data management and reproducible analytics for teaching and research. In particular, we describe in detail how CAT can be used (i) as a teaching platform with a defined software environment and data management/sharing possibilities, and (ii) to build a data analysis pipeline using the Docker technology tailored to the needs and interests of the researcher.


Assuntos
Gerenciamento de Dados , Software , Áustria
11.
Biology (Basel) ; 10(8)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34440029

RESUMO

Little phylogeographic structure is presumed for highly mobile species in pelagic zones. Lake Tanganyika is a unique ecosystem with a speciose and largely endemic fauna famous for its remarkable evolutionary history. In bathybatine cichlid fishes, the pattern of lake-wide population differentiation differs among species. We assessed the congruence between the phylogeographic structure of bathybatine cichlids and their parasitic flatworm Cichlidogyrus casuarinus to test the magnifying glass hypothesis. Additionally, we evaluated the use of a PoolSeq approach to study intraspecific variation in dactylogyrid monogeneans. The lake-wide population structure of C. casuarinus ex Hemibates stenosoma was assessed based on a portion of the cox1 gene combined with morphological characterisation. Additionally, intraspecific mitogenomic variation among 80 parasite samples from one spatially constrained metapopulation was assessed using shotgun NGS. While no clear geographic genetic structure was detected in parasites, both geographic and host-related phenotypic variation was apparent. The incongruence with the genetic north-south gradient observed in H. stenosoma may be explained by the broad host range of this flatworm including eupelagic bathybatine host species that form panmictic populations across the lake. In addition, we present the first parasite mitogenome from Lake Tanganyika and propose a methodological framework for studying the intraspecific mitogenomic variation of dactylogyrid monogeneans.

12.
Materials (Basel) ; 14(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34279308

RESUMO

High performance fiber-reinforced concrete (HPFRC) has been frequently investigated in recent years. Plenty of studies have focused on different materials and types of fibers in combination with the concrete matrix. Experimental tests show that fiber dosage improves the energy absorption capacity of concrete and enhances the robustness of concrete elements. Fiber reinforced concrete has also been illustrated to be a material for developing infrastructure sustainability in RC elements like façade plates, columns, beams, or walls. Due to increasing costs of the produced fiber reinforced concrete and to ensure the serviceability limit state of construction elements, there is a demand to analyze the necessary fiber dosage in the concrete composition. It is expected that the surface and length of used fiber in combination with their dosage influence the structure of fresh and hardened concrete. This work presents an investigation of the mechanical parameters of HPFRC with different polymer fiber dosage. Tests were carried out on a mixture with polypropylene and polyvinyl alcohol fiber with dosages of 15, 25, and 35 kg/m3 as well as with control concrete without fiber. Differences were observed in the compressive strength and in the modulus of elasticity as well as in the flexural and splitting tensile strength. The flexural tensile strength test was conducted on two different element shapes: square panel and beam samples. These mechanical properties could lead to recommendations for designers of façade elements made of HPFRC.

13.
Commun Biol ; 4(1): 516, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941844

RESUMO

Drought imposes stress on plants and associated soil microbes, inducing coordinated adaptive responses, which can involve plant-soil signalling via phytohormones. However, we know little about how microbial communities respond to phytohormones, or how these responses are shaped by chronic (long-term) drought. Here, we added three phytohormones (abscisic acid, 1-aminocyclopropane-1-carboxylic acid, and jasmonic acid) to soils from long-term (25-year), field-based climate treatments to test the hypothesis that chronic drought alters soil microbial community responses to plant stress signalling. Phytohormone addition increased soil respiration, but this effect was stronger in irrigated than in droughted soils and increased soil respiration at low phytohormone concentrations could not be explained by their use as substrate. Thus, we show that drought adaptation within soil microbial communities modifies their responses to phytohormone inputs. Furthermore, distinct phytohormone-induced shifts in microbial functional groups in droughted vs. irrigated soils might suggest that drought-adapted soil microorganisms perceive phytohormones as stress-signals, allowing them to anticipate impending drought.


Assuntos
Adaptação Fisiológica , Secas , Microbiota/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Plantas/microbiologia , Microbiologia do Solo , Solo/química , Plantas/efeitos dos fármacos
14.
Mol Ecol ; 30(4): 1005-1016, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33345416

RESUMO

Hybridization is one of the major factors contributing to the emergence of highly successful parasites. Hybrid vigour can play an important role in this process, but subsequent rounds of recombination in the hybrid population may dilute its effects. Increased fitness of hybrids can, however, be frozen by asexual reproduction. Here, we identify invasion of a 'frozen hybrid' genotype in natural populations of Gyrodactylus turnbulli, a facultatively sexual ectoparasitic flatworm that causes significant damage to its fish host. We resequenced genomes of these parasites infecting guppies from six Trinidad and Tobago populations, and found surprisingly high discrepancy in genome-wide nucleotide diversity between islands. The elevated heterozygosity on Tobago is maintained by predominantly clonal reproduction of hybrids formed from two diverged genomes. Hybridization has been followed by spread of the hybrids across the island, implying a selective advantage compared with native genotypes. Our results thus highlight that a single outcrossing event may be independently sufficient to cause pathogen expansion.


Assuntos
Doenças dos Peixes , Parasitos , Poecilia , Trematódeos , Animais , Poecilia/genética , Trematódeos/genética , Trinidad e Tobago
15.
New Phytol ; 227(3): 744-756, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32242938

RESUMO

Biodiversity-ecosystem functioning experiments found that productivity generally increases with species richness, but less is known about effects of within-species genetic richness and potential interactions between the two. While functional differences between species can explain species richness effects, empirical evidence regarding functional differences between genotypes within species and potential consequences for productivity is largely lacking. We therefore measured within- and among-species variation in functional traits and growth and determined stand-level tree biomass in a large forest experiment factorially manipulating species and genetic richness in subtropical China. Within-species variation across genetic seed families, in addition to variation across species, explained a substantial amount of trait variation. Furthermore, trait responses to species and genetic richness varied significantly within and between species. Multivariate trait variation was larger among individuals from species mixtures than those from species monocultures, but similar among individuals from genetically diverse vs genetically uniform monocultures. Correspondingly, species but not genetic richness had a positive effect on stand-level tree biomass. We argue that identifying functional diversity within and among species in forest communities is necessary to separate effects of species and genetic diversity on tree growth and community productivity.


Assuntos
Ecossistema , Árvores , Biodiversidade , Biomassa , China , Florestas , Árvores/genética
16.
Mol Ecol ; 29(8): 1494-1507, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32222008

RESUMO

Determining the molecular basis of parasite adaptation to its host is an important component in understanding host-parasite coevolution and the epidemiology of parasitic infections. Here, we investigate short- and long-term adaptive evolution in the eukaryotic parasite Gyrodactylus bullatarudis infecting Caribbean guppies (Poecilia reticulata), by comparing the reference genome of Tobagonian G. bullatarudis with other Platyhelminthes, and by analysing resequenced samples from local Trinidadian populations. At the macroevolutionary timescale, we observed duplication of G-protein and serine proteases genes, which are probably important in host-parasite arms races. Serine protease also showed strong evidence of ongoing, diversifying selection at the microevolutionary timescale. Furthermore, our analyses revealed that a hybridization event, involving two divergent genomes, followed by recombination has dramatically affected the genetic composition of Trinidadian populations. The recombinant genotypes invaded Trinidad and replaced local parasites in all populations. We localized more than 300 genes in regions fixed in local populations for variants of different origin, possibly due to diversifying selection pressure from local host populations. In addition, around 70 genes were localized in regions identified as heterozygous in some, but not all, individuals. This pattern is consistent with a very recent spread of recombinant parasites. Overall, our results are consistent with the idea that recombination between divergent genomes can result in particularly successful parasites.


Assuntos
Doenças dos Peixes , Parasitos , Poecilia , Animais , Região do Caribe , Duplicação Gênica , Humanos , Poecilia/genética , Recombinação Genética , Trinidad e Tobago
17.
Food Res Int ; 127: 108727, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31882079

RESUMO

Kale (Brassica oleracea) is a cool-season vegetable widely employed in the elaboration of diverse products such as tea and smoothies in USA or in the Northern German cuisine in wintertime. Besides, kale is gaining attention due to the diverse health benefits reported in the literature for its consumption, e.g. antigenotoxic and anticarcinogenic effect, protection of cardiovascular system and gastrointestinal tract. Low molecular weight carbohydrates (LMWC) are compounds directly related with kale flavour and nutritional quality. Despite different studies focusing on the chemical composition of kale, few information on LMWC is available. Thus, in this work a multianalytical approach was conducted in order to perform a comprehensive study of kale LMWC; their evolution during plant development and acclimation to cool temperatures was also evaluated. Gas chromatography coupled to mass spectrometry allowed the identification of 13 LMWC, being myo-inositol, galactinol, maltose and melibiose described for the first time in kale. Eight major LMWC were quantified in three different commercial kale cultivars using hydrophilic interaction liquid chromatography coupled to mass spectrometry to monitor possible differences in their content during plant development and as consequence of plant acclimation to cold temperatures. Overall, for all types of kales under study, the content of maltose and sucrose decreased during the plant development while the concentration of fructose, melibiose, maltose, raffinose and galactinol was increased in all kale types exposed to low temperatures. These results underline the importance of controlling the temperature during kale cultivation in order to obtain products with a high nutritional value.


Assuntos
Aclimatação , Brassica/metabolismo , Carboidratos/química , Temperatura Baixa , Cromatografia Gasosa-Espectrometria de Massas/métodos , Brassica/química , Brassica/crescimento & desenvolvimento
18.
Sci Rep ; 9(1): 19646, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873145

RESUMO

Elucidating the genetic basis of phenotypic variation in response to different environments is key to understanding how populations evolve. Facultatively sexual rotifers can develop adaptive responses to fluctuating environments. In a previous evolution experiment, diapause-related traits changed rapidly in response to two selective regimes (predictable vs unpredictable) in laboratory populations of the rotifer Brachionus plicatilis. Here, we investigate the genomic basis of adaptation to environmental unpredictability in these experimental populations. We identified and genotyped genome-wide polymorphisms in 169 clones from both selective regimes after seven cycles of selection using genotyping by sequencing (GBS). Additionally, we used GBS data from the 270 field clones from which the laboratory populations were established. This GBS dataset was used to identify candidate SNPs under selection. A total of 76 SNPs showed divergent selection, three of which are candidates for being under selection in the particular unpredictable fluctuation pattern studied. Most of the remaining SNPs showed strong signals of adaptation to laboratory conditions. Furthermore, a genotype-phenotype association approach revealed five SNPs associated with two key life-history traits in the adaptation to unpredictability. Our results contribute to elucidating the genomic basis for adaptation to unpredictable environments and lay the groundwork for future evolution studies in rotifers.


Assuntos
Aclimatação/fisiologia , Genoma , Polimorfismo de Nucleotídeo Único , Rotíferos/fisiologia , Seleção Genética , Animais , Bases de Dados de Ácidos Nucleicos , Estudos de Associação Genética
19.
Methods Mol Biol ; 1963: 195-213, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30875055

RESUMO

Recent methodological advances have transformed the field of ancient DNA (aDNA). Basic bioinformatics skills are becoming essential requirements to process and analyze the sheer amounts of data generated by current aDNA studies and in biomedical research in general. This chapter is intended as a practical guide to the assembly of ancient mitochondrial genomes, directly from genomic DNA-derived next-generation sequencing (NGS) data, specifically in the absence of closely related reference genomes. In a hands-on tutorial suitable for readers with little to no prior bioinformatics experience, we reconstruct the mitochondrial genome of a woolly mammoth deposited ~45,000 years ago. We introduce key software tools and outline general strategies for mitogenome assembly, including the critical quality assessment of assembly results without a reference genome.


Assuntos
DNA Antigo/análise , DNA Mitocondrial/genética , Genoma Mitocondrial , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/normas , Humanos , Padrões de Referência , Análise de Sequência de DNA/métodos , Software
20.
Mol Ecol ; 28(2): 471-483, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29485216

RESUMO

Determining the host-parasitoid interactions and parasitism rates for invasive species entering novel environments is an important first step in assessing potential routes for biocontrol and integrated pest management. Conventional insect rearing techniques followed by taxonomic identification are widely used to obtain such data, but this can be time-consuming and prone to biases. Here, we present a next-generation sequencing approach for use in ecological studies which allows for individual-level metadata tracking of large numbers of invertebrate samples through the use of hierarchically organised molecular identification tags. We demonstrate its utility using a sample data set examining both species identity and levels of parasitism in late larval stages of the oak processionary moth (Thaumetopoea processionea-Linn. 1758), an invasive species recently established in the United Kingdom. Overall, we find that there are two main species exploiting the late larval stages of oak processionary moth in the United Kingdom with the main parasitoid (Carcelia iliaca-Ratzeburg, 1840) parasitising 45.7% of caterpillars, while a rare secondary parasitoid (Compsilura concinnata-Meigen, 1824) was also detected in 0.4% of caterpillars. Using this approach on all life stages of the oak processionary moth may demonstrate additional parasitoid diversity. We discuss the wider potential of nested tagging DNA metabarcoding for constructing large, highly resolved species interaction networks.


Assuntos
Código de Barras de DNA Taxonômico , Interações Hospedeiro-Parasita/genética , Espécies Introduzidas , Lepidópteros/parasitologia , Animais , Ecossistema , Larva/genética , Larva/parasitologia , Lepidópteros/genética , Mariposas/genética , Reino Unido , Vespas/genética , Vespas/parasitologia
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