| 1. |
- Sanli, Kemal, et al.
(författare)
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Metagenomic Sequencing of Marine Periphyton: Taxonomic and Functional Insights into Biofilm Communities
- 2015
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Ingår i: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 6:1192
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Tidskriftsartikel (refereegranskat)abstract
- Periphyton communities are complex phototrophic, multispecies biofilms that develop on surfaces in aquatic environments. These communities harbor a large diversity of organisms comprising viruses, bacteria, algae, fungi, protozoans and metazoans. However, thus far the total biodiversity of periphyton has not been described. In this study, we use metagenomics to characterize periphyton communities from the marine environment of the Swedish west coast. Although we found approximately ten times more eukaryotic rRNA marker gene sequences compared to prokaryotic, the whole metagenome-based similarity searches showed that bacteria constitute the most abundant phyla in these biofilms. We show that marine periphyton encompass a range of heterotrophic and phototrophic organisms. Heterotrophic bacteria, including the majority of proteobacterial clades and Bacteroidetes, and eukaryotic macro-invertebrates were found to dominate periphyton. The phototrophic groups comprise Cyanobacteria and the alpha-proteobacterial genus Roseobacter, followed by different micro- and macro-algae. We also assess the metabolic pathways that predispose these communities to an attached lifestyle. Functional indicators of the biofilm form of life in periphyton involve genes coding for enzymes that catalyze the production and degradation of extracellular polymeric substances, mainly in the form of complex sugars such as starch and glycogen-like meshes together with chitin. Genes for 278 different transporter proteins were detected in the metagenome, constituting the most abundant protein complexes. Finally, genes encoding enzymes that participate in anaerobic pathways, such as denitrification and methanogenesis, were detected suggesting the presence of anaerobic or low-oxygen micro-zones within the biofilms.
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| 2. |
- Sigvald, Roland, et al.
(författare)
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Molecular identification of bloodmeals and species composition in Culicoides biting midges
- 2013
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Ingår i: Medical and Veterinary Entomology. - : Wiley. - 0269-283X .- 1365-2915. ; 27, s. 104-112
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Tidskriftsartikel (refereegranskat)abstract
- Investigations of host preferences in haematophagous insects, including Culicoides biting midges (Diptera: Ceratopogonidae), are critical in order to assess transmission routes of vector-borne diseases. In this study, we collected and morphologically identified 164 blood-engorged Culicoides females caught in both light traps and permanent 12-m high suction traps during 20082010 in Sweden. Molecular analysis of the mitochondrial cytochrome c oxidase subunit I (COI) gene in the biting midges was performed to verify species classification, discern phylogenetic relationships and uncover possible cryptic species. Bloodmeal analysis using universal vertebrate cytochrome b primers revealed a clear distinction in host selection between mammalophilic and ornithophilic Culicoides species. Host sequences found matches in horse (n = 59), sheep (n = 39), cattle (n = 26), Eurasian elk (n = 1) and 10 different bird species (n = 18). We identified 15 Culicoides species previously recorded in Scandinavia and four additional species haplotypes that were distinctly different from the described species. All ornithophilic individuals (n = 23) were caught exclusively in the suction traps, as were, interestingly, almost all mammalophilic species (n = 41), indicating that many biting midge species may be able to cover long distances after completing a bloodmeal. These results add new information on the composition of Culicoides species and their host preferences and their potential long-distance dispersal while blood-engorged.
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| 3. |
- Alm Rosenblad, Magnus, 1957, et al.
(författare)
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Detection of signal recognition particle (SRP) RNAs in the nuclear ribosomal internal transcribed spacer 1 (ITS1) of three lineages of ectomycorrhizal fungi (Agaricomycetes, Basidiomycota)
- 2016
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Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 13, s. 21-33
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Tidskriftsartikel (refereegranskat)abstract
- During a routine scan for Signal Recognition Particle (SRP) RNAs in eukaryotic sequences, we surprisingly found in silico evidence in GenBank for a 265-base long SRP RNA sequence in the ITS1 region of a total of 11 fully identified species in three ectomycorrhizal genera of the Basidiomycota (Fungi): Astraeus, Russula, and Lactarius. To rule out sequence artifacts, one specimen from a species indicated to have the SRP RNA-containing ITS region in each of these genera was ordered and re-sequenced. Sequences identical to the corresponding GenBank entries were recovered, or in the case of a non-original but conspecific specimen differed by three bases, showing that these species indeed have an SRP RNA sequence incorporated into their ITS1 region. Other than the ribosomal genes, this is the first known case of non-coding RNAs in the eukaryotic ITS region, and it may assist in the examination of other types of insertions in fungal genomes.
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| 4. |
- Zhao, M., et al.
(författare)
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Phylogenetic position of the Wallcreeper Tichodroma muraria
- 2016
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Ingår i: Journal of Ornithology = Journal fur Ornithologie. - : Springer Science and Business Media LLC. - 0021-8375 .- 1439-0361. ; 157:3, s. 913-918
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Tidskriftsartikel (refereegranskat)abstract
- The Wallcreeper Tichodroma muraria is usually placed in a monotypic family or subfamily within the superfamily Certhioidea, with assumed close relationships to Certhia (treecreepers), Sitta (nuthatches) and Salpornis (spotted creepers). Previous studies have suggested that Tichodroma is most closely related to Sitta, alternatively to Salpornis. We analysed the relationships of Tichodroma using two mitochondrial and five nuclear loci. The tree based on concatenated sequences strongly supported a sister relationship between Tichodroma and Sitta, as well as between Salpornis and Certhia. However, species tree analysis (MP-EST) was unable to resolve these relationships, and although the concatenation tree remains the best hypothesis, more data are needed to corroborate this. © 2016, Dt. Ornithologen-Gesellschaft e.V.
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| 5. |
- Subhash, Santhilal, 1987, et al.
(författare)
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Sperm Originated Chromatin Imprints and LincRNAs in Organismal Development and Cancer
- 2020
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Ingår i: iScience. - : Elsevier BV. - 2589-0042. ; 23:6
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Tidskriftsartikel (refereegranskat)abstract
- Importance of sperm-derived transcripts and chromatin imprints in organismal development is poorly investigated. Here using an integrative approach, we show that human sperm transcripts are equally important as oocyte. Sperm-specific and sperm-oocyte common transcripts carry distinct chromatin structures at their promoters correlating with corresponding transcript levels in sperm. Interestingly, sperm-specific H3K4me3 patterns at the lincRNA promoters are not maintained in the germ layers and somatic tissues. However, bivalent chromatin at the sperm-specific protein-coding gene promoters is maintained throughout the development. Sperm-specific transcripts reach their peak expression during zygotic genome activation, whereas sperm-oocyte common transcripts are present during early preimplantation development but decline at the onset of zygotic genome activation. Additionally, there is an inverse correlation between sperm-specific and sperm-oocyte lincRNAs throughout the development. Sperm-lincRNAs also show aberrant activation in tumors. Overall, our observations indicate that sperm transcripts carrying chromatin imprints may play an important role in human development and cancer.
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| 6. |
- Tedersoo, Leho, et al.
(författare)
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Novel soil-inhabiting clades fill gaps in the fungal tree of life
- 2017
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Ingår i: Microbiome. - : Springer Science and Business Media LLC. - 2049-2618. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Background - Fungi are a diverse eukaryotic group of degraders, pathogens, and symbionts, with many lineages known only from DNA sequences in soil, sediments, air, and water. Results - We provide rough phylogenetic placement and principal niche analysis for >40 previously unrecognized fungal groups at the order and class level from global soil samples based on combined 18S (nSSU) and 28S (nLSU) rRNA gene sequences. Especially, Rozellomycota (Cryptomycota), Zygomycota s.lat, Ascomycota, and Basidiomycota are rich in novel fungal lineages, most of which exhibit distinct preferences for climate and soil pH. Conclusions - This study uncovers the great phylogenetic richness of previously unrecognized order- to phylum-level fungal lineages. Most of these rare groups are distributed in different ecosystems of the world but exhibit distinct ecological preferences for climate or soil pH. Across the fungal kingdom, tropical and non-tropical habitats are equally likely to harbor novel groups. We advocate that a combination of traditional and high-throughput sequencing methods enable efficient recovery and phylogenetic placement of such unknown taxonomic groups.
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| 7. |
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| 8. |
- Hallenberg, Nils, 1947, et al.
(författare)
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Pseudolagarobasidium (Basidiomycota): on the reinstatement of a genus of parasitic, saprophytic, and endophytic resupinate fungi
- 2008
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Ingår i: Botany. - 1916-2804. ; 86:11, s. 1319-1325
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Tidskriftsartikel (refereegranskat)abstract
- The small resupinate genus Pseudolagarobasidium (Polyporales, Basidiomycota) presently comprises less than five species, all of which were described from tropical to subtropical regions, and two of which are root parasites on leguminous trees. The genus has recently been synonymized with Radulodon on morphological grounds, and the present study evaluates this proposal in a molecular context. Pseudolagarobasidium was found to constitute a well supported, monophyletic group excluding Radulodon and this synonymy is rejected. The ecological range of the genus spans saprotrophy to parasitism, and this study presents evidence that at least one lineage in Pseudolagarobasidium is endophytic in the cacao tree (Theobroma cacao L.). Key words: Polyporales, Radulodon, phylogeny, plant interactions. Résumé: Le Pseudolagarobasidium (Polyporales, Basidiomycota) constitue un genre de petits champignons résupinés qui comporte actuellement cinq espèces, toutes décrites à partir de régions tropicales ou subtropicales, incluant deux espèces parasites des racines d'arbres de la famille des légumineuses. On en a récemment établi la synonymie avec le genre Radulodon sur la base morphologique, mais les auteurs utilisent ici l'approche moléculaire. On constate que le genre Pseudolagarobasidium constitue un groupe monophylétique robuste excluant les Radulodon ce qui conduit au rejet de cette synonymie. L'amplitude écologique du genre va du saprophytisme au parasitisme, et on présente des preuves qu'au moins une lignée est un endophyte du cacaoyer (Theobroma cacao L.). Mots-clés : Polyporales, Radulon, phylogénie, interactions végétales.
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| 9. |
- Hooper, D. M., et al.
(författare)
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The Rusty-tailed Flycatcher (Muscicapa ruficauda; Ayes: Muscicapidae) is a member of the genus Ficedula
- 2016
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 102, s. 56-61
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Tidskriftsartikel (refereegranskat)abstract
- The phylogenetic relationships of the avian family Muscicapidae (Old World chats and flycatchers) have historically been enigmatic and remain an active area of study. Widespread instances of non-monophyly resulting from misleading morphological and behavioral similarities have merited numerous taxonomic revisions to the group. Here we report one such instance with regard to the Rusty-tailed Flycatcher Muscicapa ruficauda, which has recently been placed in the newly proposed monotypic genus Ripleyia, due to inferred sister relationship to the genus Muscicapa and related genera (Voelker et al., 2016a). This name was later replaced by Ripleyornis, as it was realized that Ripleyia is a junior homonym of a genus of Mollusca (Voelker et al., 2016b). Using a Bayesian phylogenetic assessment of the Muscicapidae with near-complete taxon sampling of the genus Ficedula for five loci, along with an acoustic comparison of M. ruficauda to a subset of other flycatcher species, we show that this species should be reassigned to the genus Ficedula and accordingly that the names Ripleyia and Ripleyornis are both junior synonyms of Ficedula. (C) 2016 Elsevier Inc. All rights reserved.
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| 10. |
- Li, Xinlei, et al.
(författare)
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Shaped by uneven Pleistocene climate: mitochondrial phylogeographic pattern and population history of White Wagtail Motacilla alba (Aves: Passeriformes).
- 2016
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Ingår i: Journal of Avian Biology. - : Wiley. - 0908-8857 .- 1600-048X. ; 47, s. 263-274
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Tidskriftsartikel (refereegranskat)abstract
- We studied the phylogeography and population history of the white wagtail Motacilla alba, which has a vast breeding range, covering areas with different Pleistocene climatic histories. The mitochondrial NADH dehydrogenase subunit II gene (ND2) and Control Region (CR) were analyzed for 273 individuals from 45 localities. Our data comprised all nine subspecies of white wagtail. Four primary clades were inferred (M, N, SW and SE), with indications of M. grandis being nested within M. alba. The oldest split was between two haplotypes from the endemic Moroccan M. a. subpersonata (clade M) and the others, at 0.63–0.96 Mya; other divergences were at 0.31–0.38 Mya. The entire differentiation falls within the part of the Pleistocene characterized by Milankovitch cycles of large amplitudes and durations. Clade N was distributed across the northern Palearctic; clade SW in southwestern Asia plus the British Isles and was predicted by Ecological niche models (ENMs) to occur also in central and south Europe; and clade SE was distributed in central and east Asia. e deep divergence within M. a. subpersonata may reflect retention of ancestral haplotypes. Regional differences in historical climates have had different impacts on different populations: clade N expanded after the last glacial maximum (LGM), whereas milder Pleistocene climate of east Asia allowed clade SE a longer expansion time (since MIS 5); clade SW expanded over a similarly long time as clade SE, which is untypical for European species. ENMs supported these conclusions in that the northern part of the Eurasian continent was unsuitable during the LGM, whereas southern parts remained suitable. e recent divergences and poor structure in the mitochondrial tree contrasts strongly with the pronounced, well defined phenotypical differentiation, indicating extremely fast plumage divergence.
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| 11. |
- Olsson, Urban, 1954, et al.
(författare)
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Mitochondrial phylogeny of the Eurasian/African reed warbler complex (Acrocephalus, Aves). Disagreement between morphological and molecular evidence and cryptic divergence: A case for resurrecting Calamoherpe ambigua Brehm 1857
- 2016
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 102, s. 30-44
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Tidskriftsartikel (refereegranskat)abstract
- A tree based on the mitochondrial cyt b gene for 278 samples from throughout the range of the Eurasian Reed Warbler Acrocephalus scirpaceus - African Reed Warbler A. baeticatus complex shows well supported geographically structured divergence for eight distinct lineages. The phylogenetic structuring together with the clarification of priority, provided by sequence data from seven type specimens, suggests that both taxonomy and distribution boundaries are in need of revision. The Iberian and Moroccan populations form a well-supported Glade, and we propose that these are treated as taxonomically distinct, under the name ambiguus (Brehm, 1857). We propose that the names scirpaceus, fuscus, avicenniae, ambiguus, minor, cinnamomeus, hallae and baeticatus are used for the well supported clades in the complex, which we recommend to treat as one polytypic species, A. scirpaceus, pending studies of gene flow and assortative mating in the contact zones. (C) 2016 Elsevier Inc. All rights reserved.
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| 12. |
- Wintersparv Stervander, Martin, et al.
(författare)
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Multiple instances of paraphyletic species and cryptic taxa revealed by mitochondrial and nuclear RAD data for Calandrella larks (Aves: Alaudidae)
- 2016
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 102, s. 233-245
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Tidskriftsartikel (refereegranskat)abstract
- The avian genus Calandrella (larks) was recently suggested to be non-monophyletic, and was divided into two genera, of which Calandrella sensu stricto comprises 4-5 species in Eurasia and Africa. We analysed mitochondrial cytochrome b (cytb) and nuclear Restriction-site Associated DNA (RAD) sequences from all species, and for cytb we studied 21 of the 22 recognised subspecies, with the aim to clarify the phylogenetic relationships within the genus and to compare large-scale nuclear sequence patterns with a widely used mitochondrial marker. Cytb indicated deep splits among the currently recognised species, although it failed to support the interrelationships among most of these. It also revealed unexpected deep divergences within C. brachydactyla, C. blanfordi/C erlangeri, C. cinerea, and C. acutirostris. It also suggested that both C. brachydactyla and C. blanfordi, as presently circumscribed, are paraphyletic. In contrast, most of the many subspecies of C brachydactyla and C. cinerea were unsupported by cytb, although two populations of C. cinerea were found to be genetically distinct. The RAD data corroborated the cytb tree (for the smaller number of taxa analysed) and recovered strongly supported interspecific relationships. However, coalescence analyses of the RAD data, analysed in SNAPP both with and without an outgroup, received equally strong support for two conflicting topologies. We suggest that the tree rooted with an outgroup - which is not recommended for SNAPP - is more trustworthy, and suggest that the reliability of analyses performed without any outgroup species should be thoroughly evaluated. We also demonstrate that degraded museum samples can be phylogenetically informative in RAD analyses following careful bioinformatic treatment. We note that the genus Calandrella is in need of taxonomic revision. (C) 2016 Elsevier Inc. All rights reserved.
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| 13. |
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| 14. |
- Bienert, Gern, 2008, et al.
(författare)
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A subgroup of plant aquaporins facilitate the bi-directional diffusion of As(OH)3 and Sb(OH)3 across membranes
- 2008
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Ingår i: BMC Biology. - : Springer Science and Business Media LLC. - 1741-7007. ; 6:26
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Tidskriftsartikel (refereegranskat)abstract
- Background Arsenic is a toxic and highly abundant metalloid that endangers human health through drinking water and the food chain. The most common forms of arsenic in the environment are arsenate (As(V)) and arsenite (As(III)). As(V) is a non-functional phosphate analog that enters the food chain via plant phosphate transporters. Inside cells, As(V) becomes reduced to As(III) for subsequent extrusion or compartmentation. Although much is known about As(III) transport and handling in microbes and mammals, the transport systems for As(III) have not yet been characterized in plants. Results Here we show that the Nodulin26-like Intrinsic Proteins (NIPs) AtNIP5;1 and AtNIP6;1 from Arabidopsis thaliana, OsNIP2;1 and OsNIP3;2 from Oryza sativa, and LjNIP5;1 and LjNIP6;1 from Lotus japonicus are bi-directional As(III) channels. Expression of these NIPs sensitized yeast cells to As(III) and antimonite (Sb(III)), and direct transport assays confirmed their ability to facilitate As(III) transport across cell membranes. On medium containing As(V), expression of the same NIPs improved yeast growth, probably due to increased As(III) efflux. Our data furthermore provide evidence that NIPs can discriminate between highly similar substrates and that they may have differential preferences in the direction of transport. A subgroup of As(III) permeable channels that group together in a phylogenetic tree required N-terminal truncation for functional expression in yeast. Conclusion This is the first molecular identification of plant As(III) transport systems and we propose that metalloid transport through NIPs is a conserved and ancient feature. Our observations are potentially of great importance for improved remediation and tolerance of plants, and may provide a key to the development of low arsenic crops for food production.
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| 15. |
- Eriksson, Martin, 1970, et al.
(författare)
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Triclosan changes community composition and selects for specific bacterial taxa in marine periphyton biofilms in low nanomolar concentrations
- 2020
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Ingår i: Ecotoxicology. - : Springer Science and Business Media LLC. - 0963-9292 .- 1573-3017. ; 29:7, s. 1083-1094
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Tidskriftsartikel (refereegranskat)abstract
- The antibacterial agent Triclosan (TCS) is a ubiquitous environmental contaminant due to its widespread use. Sensitivity to TCS varies substantially among eu- and pro-karyotic species and its risk for the marine environment remains to be better elucidated. In particular, the effects that TCS causes on marine microbial communities are largely unknown. In this study we therefore used 16S amplicon rDNA sequencing to investigate TCS effects on the bacterial composition in marine periphyton communities that developed under long-term exposure to different TCS concentrations. Exposure to TCS resulted in clear changes in bacterial composition already at concentrations of 1 to 3.16 nM. We conclude that TCS affects the structure of the bacterial part of periphyton communities at concentrations that actually occur in the marine environment. Sensitive taxa, whose abundance decreased significantly with increasing TCS concentrations, include the Rhodobiaceae and Rhodobacteraceae families of Alphaproteobacteria, and unidentified members of the Candidate division Parcubacteria. Tolerant taxa, whose abundance increased significantly with higher TCS concentrations, include the families Erythrobacteraceae (Alphaproteobacteria), Flavobacteriaceae (Bacteroidetes), Bdellovibrionaceae (Deltaproteobacteria), several families of Gammaproteobacteria, and members of the Candidate phylum Gracilibacteria. Our results demonstrate the variability of TCS sensitivity among bacteria, and that TCS can change marine bacterial composition at concentrations that have been detected in the marine environment.
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| 16. |
- Janzon, Anders, 1978, et al.
(författare)
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Exploring the microbial resistome in river sediments exposed to extraordinary high levels of antibiotics
- 2010
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Ingår i: 35th FEBS Congress: Molecules of Life.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The rapid development and propagation of antibiotic resistance in pathogenic and opportunistic bacteria is a major threat to public health worldwide. The phenomenon has been widely studied in the clinical setting, but comparatively little is known about the prevalence and diversity of antibiotic resistance in communities of environmental bacteria, often referred to as the environmental resistome. As the external environment may function as a reservoir of resistance genes to human pathogens, we are interested in how environmental bacteria are affected by antibiotic pollution. We have previously isolated microbial DNA from river sediments taken up- and downstream from a water treatment plant that processes waste water from several pharmaceutical plants producing antibiotics. In a previous study, we used deep sequencing to identify unprecedented frequencies of known resistance genes to several classes of antibiotics in these samples. In this study, we aim to functionally characterize the resistome in a more open and exploratory way by screening genomic DNA libraries transformed into sensitive hosts. To generate the libraries, several experimental strategies were explored, including mechanical shearing and enzymatic digestion of the isolated DNA followed by blunt- or sticky end cloning into different plasmids, subsequently transformed into sensitive E. coli. Pros and cons of the different strategies will be discussed along with preliminary results of the screening against selected antibiotics.
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Sandström, Olof, et al.
(författare)
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Miljöpåverkan av skogsindustriutsläpp
- 1997
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Ingår i: Naturvårdsverkets rapportserie. Rapport 4695. ; , s. 1-89
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 21. |
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| 22. |
- Stenberg, Simon, et al.
(författare)
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Control of mitochondrial superoxide production includes programmed mtDNA deletion and restoration
- 2020
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Deletion of mitochondrial DNA in eukaryotes is mainly attributed to rare accidental events associated with mitochondrial replication or repair of double-strand breaks. We report the discovery that yeast cells arrest harmful intramitochondrial superoxide production by shutting down respiration through genetically controlled deletion of mitochondrial oxidative phosphorylation genes. We show that the regulatory circuitry underlying this editing critically involves the antioxidant enzyme superoxide dismutase 2 and two-way mitochondrial-nuclear communication. While mitochondrial DNA homeostasis is rapidly restored after cessation of a short-term superoxide stress, long-term stress causes maladaptive persistence of the deletion process, leading to complete annihilation of the cellular pool of intact mitochondrial genomes and irrevocable loss of respiratory ability. Our results may therefore be of etiological as well as therapeutic importance with regard to age-related mitochondrial impairment and disease.One-Sentence SummaryGenetically controlled editing of mitochondrial DNA is an integral part of the yeast’s defenses against oxidative damage.
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| 23. |
- Wieloch, Thomas, 1979-, et al.
(författare)
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Intramolecular carbon isotope signals reflect metabolite allocation in plants
- 2022
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Ingår i: Journal of Experimental Botany. - : Oxford University Press. - 0022-0957 .- 1460-2431. ; 73:8, s. 2558-2575
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Stable isotopes at natural abundance are key tools to study physiological processes occurring outside the temporal scope of manipulation and monitoring experiments. Whole-molecule carbon isotope ratios (13C/12C) enable assessments of plant carbon uptake yet conceal information about carbon allocation. Here, we identify an intramolecular 13C/12C signal at tree-ring glucose C-5 and C-6 and develop experimentally testable theories on its origin. More specifically, we assess the potential of processes within C3 metabolism for signal introduction based (inter alia) on constraints on signal propagation posed by metabolic networks. We propose that the intramolecular signal reports carbon allocation into major metabolic pathways in actively photosynthesizing leaf cells including the anaplerotic, shikimate, and non-mevalonate pathway. We support our theoretical framework by linking it to previously reported whole-molecule 13C/12C increases in cellulose of ozone-treated Betula pendula and a highly significant relationship between the intramolecular signal and tropospheric ozone concentration. Our theory postulates a pronounced preference for leaf cytosolic triose-phosphate isomerase to catalyse the forward reaction in vivo (dihydroxyacetone phosphate to glyceraldehyde 3-phosphate). In conclusion, intramolecular 13C/12C analysis resolves information about carbon uptake and allocation enabling more comprehensive assessments of carbon metabolism than whole-molecule 13C/12C analysis.
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| 24. |
- Alström, Per, et al.
(författare)
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Multilocus phylogeny of the avian family Alaudidae (larks) reveals complex morphological evolution, non-monophyletic genera and hidden species diversity
- 2013
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 69:3, s. 1043-1056
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Tidskriftsartikel (refereegranskat)abstract
- The Alaudidae (larks) is a large family of songbirds in the superfamily Sylvioidea. Larks are cosmopolitan, although species-level diversity is by far largest in Africa, followed by Eurasia, whereas Australasia and the New World have only one species each. The present study is the first comprehensive phylogeny of the Alaudidae. It includes 83.5% of all species and representatives from all recognised genera, and was based on two mitochondrial and three nuclear loci (in total 6.4 kbp, although not all loci were available for all species). In addition, a larger sample, comprising several subspecies of some polytypic species was analysed for one of the mitochondrial loci. There was generally good agreement in trees inferred from different loci, although some strongly supported incongruences were noted. The tree based on the concatenated multilocus data was overall well resolved and well supported by the data. We stress the importance of performing single gene as well as combined data analyses, as the latter may obscure significant incongruence behind strong nodal support values. The multilocus tree revealed many unpredicted relationships, including some non-monophyletic genera (Calandrella, Mirafra, Melanocorypha, Spizocorys). The tree based on the extended mitochondrial data set revealed several unexpected deep divergences between taxa presently treated as conspecific (e.g. within Ammomanes cinctura, Ammomanes deserti, Calandrella brachydactyla, Eremophila alpestris), as well as some shallow splits between currently recognised species (e.g. Certhilauda brevirostris-C semitorquata-C curvirostris; Calendulauda barlowi-C. erythrochlamys; Mirafra cantillans-M. javanica). Based on our results, we propose a revised generic classification, and comment on some species limits. We also comment on the extraordinary morphological adaptability in larks, which has resulted in numerous examples of parallel evolution (e.g. in Melanocorypha mongolica and Alauda leucoptera [both usually placed in Melanocorypha]; Ammomanopsis grayi and Ammomanes cinctura/deserti [former traditionally placed in Ammomanes]; Chersophilus duponti and Certhilauda spp.; Eremopterix hova [usually placed in Mirafra] and several Mirafra spp.), as well as both highly conserved plumages (e.g. within Mirafra) and strongly divergent lineages (e.g. Eremopterix hova vs. other Eremopterix spp.; Calandrella cinerea complex vs. Eremophila spp.; Eremalauda dunni vs. Chersophilus duponti; Melanocorypha mongolica and male M. yeltoniensis vs. other Melanocoupha spp. and female M. yeltoniensis). Sexual plumage dimorphism has evolved multiple times. Few groups of birds show the same level of disagreement between taxonomy based on morphology and phylogenetic relationships as inferred from DNA sequences. (C) 2013 Elsevier Inc. All rights reserved.
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| 25. |
- Lindahl, Björn, et al.
(författare)
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Fungal community analysis by high-throughput sequencing of amplified markers – a user's guide
- 2013
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 199:1, s. 288-299
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Forskningsöversikt (refereegranskat)abstract
- * Novel high-throughput sequencing methods outperform earlier approaches in terms of resolution and magnitude. They enable identification and relative quantification of community members and offer new insights into fungal community ecology. These methods are currently taking over as the primary tool to assess fungal communities of plant-associated endophytes, pathogens, and mycorrhizal symbionts, as well as free-living saprotrophs. * Taking advantage of the collective experience of six research groups, we here review the different stages involved in fungal community analysis, from field sampling via laboratory procedures to bioinformatics and data interpretation. We discuss potential pitfalls, alternatives, and solutions. * Highlighted topics are challenges involved in: obtaining representative DNA/RNA samples and replicates that encompass the targeted variation in community composition, selection of marker regions and primers, options for amplification and multiplexing, handling of sequencing errors, and taxonomic identification. * Without awareness of methodological biases, limitations of markers, and bioinformatics challenges, large-scale sequencing projects risk yielding artificial results and misleading conclusions.
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