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  • 1.
    Abromaitis, V.
    et al.
    Kaunas Univ Technol, Lithuania ; Wetsus, European Ctr Excellence Sustainable Water Technol, Netherlands.
    Racys, V.
    Kaunas Univ Technol, Lithuania.
    van der Marel, P.
    WLN, Netherlands.
    Ni, Gaofeng
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Dopson, Mark
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Wolthuizen, A. L.
    Wageningen Univ, Netherlands.
    Meulepas, R. J. W.
    Wetsus, European Ctr Excellence Sustainable Water Technol, Netherlands.
    Effect of shear stress and carbon surface roughness on bioregeneration and performance of suspended versus attached biomass in metoprolol-loaded biological activated carbon systems2017In: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 317, p. 503-511Article in journal (Refereed)
    Abstract [en]

    The bioregeneration of activated carbon (AC) in biological activated carbon (BAC) systems is limited by sorption-desorption hysteresis and transport between the adsorbent and biomass. In this study, we investigated these limitations and whether a biofilm covering the AC surface is required. Consequently, BAC reactors were operated at different shear stress and AC surface smoothness, since this may affect biofilm formation. The experiments were carried out in BAC and blank reactors treating synthetic wastewater containing the pharmaceutical metoprolol. After start-up, all reactors removed metoprolol completely; however, after 840 h the removal dropped due to saturation of the AC. In the blank reactors, the removal dropped to 0% while in the BAC reactors removal recovered to >99%, due to increased biological activity. During the initial phase, the metoprolol was adsorbed, rather than biodegraded. At the end, the AC from the BAC reactors had higher pore volume and sorption capacity than from the blank reactors, showing that the AC had been bioregenerated. At high shear (G = 25 s(-1)), the rough AC granules (R-a = 13 mu m) were covered with a 50-400 gm thick biofilm and the total protein content of the biofilm was 2.6 mg/gAC, while at lower shear (G = 8.8 s(-1)) the rough AC granules were only partly covered. The biofilm formation at lower shear (G = 8.8 s(-1)) on smooth AC granules (R-a = 1.6 mu m) was negligible. However, due to the presence of suspended biomass the reactor performance or bioregeneration were not reduced. This showed that direct contact between the AC and biomass was not essential in mixed BAC systems. The microbial analyses of the suspended biomass and the biofilm on AC surface indicated that metoprolol was mainly biodegraded in suspension. (C) 2017 Elsevier B.V. All rights reserved.

  • 2.
    Abudaya, Mohammed
    et al.
    Natl Res Ctr, Palestine.
    Ulman, Aylin
    Univ British Columbia, Canada.
    Salah, Jehad
    Minist Agr, Palestine.
    Fernando, Daniel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Manta Trust, UK;Blue Resources Trust, Sri Lanka.
    Wor, Catarina
    Univ British Columbia, Canada.
    di Sciara, Giuseppe Notarbartolo
    Tethys Res Inst, Italy.
    Speak of the devil ray (Mobula mobular) fishery in Gaza2018In: Reviews in Fish Biology and Fisheries, ISSN 0960-3166, E-ISSN 1573-5184, Vol. 28, no 1, p. 229-239Article in journal (Refereed)
    Abstract [en]

    Little is known about the giant devil ray (Mobula mobular), an endangered species endemic to the Mediterranean. Gaza is the only region where this species is targeted, hence, this fishery was studied to address the knowledge gap on fishery interactions, species behavior, and life-history traits. Devil rays have been frequenting this maritime area for at least the past 50 years for a short window from February to April. Landings are reported from 2005 to 2016, along with disc-width (DW) measurements for recent years. A total of 304 M. mobular (over 90% males) were landed in Gaza from 2014 to 2016, most which were mature and appeared to be mating (over 90% of males had sperm-filled claspers), providing critical insight that this area may serve as a mating ground. Yearly landings are shown here to closely match the allowed fishing distance from shore, which changes regularly, indicating that the rays are normally caught between 6 and 12 n.m. offshore. Width-weight conversion parameters are calculated for the first time for this species: a = 2.68 x 10(-6) and b = 4.39. Fresh protein drives this local fishery, as food security is a major issue. An export market for gill plates was reported intermittently, and is no longer possible due to strict trade restrictions. We highlight the lack of awareness of fishers regarding the IUCN's Red List 'Endangered' status of devil rays, and stress the urgent need for national protection of this species, particularly due to the species' very slow life-history traits and probable usage of this area as a mating ground.

  • 3.
    Acuna, Lillian G.
    et al.
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Pablo Cardenas, Juan
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Covarrubias, Paulo C.
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Jose Haristoy, Juan
    Fundación Ciencia & Vida, Chile.
    Flores, Rodrigo
    Fundación Ciencia & Vida, Chile.
    Nuñez, Harold
    Fundación Ciencia & Vida, Chile.
    Riadi, Gonzalo
    Universidad de Talca, Chile.
    Shmaryahu, Amir
    Fundación Ciencia & Vida, Chile.
    Valdes, Jorge
    Center for Systems Biotechnology, Chile.
    Dopson, Mark
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Rawlings, Douglas E.
    University of Stellenbosch, South Africa.
    Banfield, Jillian F.
    University of California, USA.
    Holmes, David S.
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Quatrini, Raquel
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Architecture and Gene Repertoire of the Flexible Genome of the Extreme Acidophile Acidithiobacillus caldus2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 11, article id e78237Article in journal (Refereed)
    Abstract [en]

    Background: Acidithiobacillus caldus is a sulfur oxidizing extreme acidophile and the only known mesothermophile within the Acidithiobacillales. As such, it is one of the preferred microbes for mineral bioprocessing at moderately high temperatures. In this study, we explore the genomic diversity of A. caldus strains using a combination of bioinformatic and experimental techniques, thus contributing first insights into the elucidation of the species pangenome. Principal Findings: Comparative sequence analysis of A. caldus ATCC 51756 and SM-1 indicate that, despite sharing a conserved and highly syntenic genomic core, both strains have unique gene complements encompassing nearly 20% of their respective genomes. The differential gene complement of each strain is distributed between the chromosomal compartment, one megaplasmid and a variable number of smaller plasmids, and is directly associated to a diverse pool of mobile genetic elements (MGE). These include integrative conjugative and mobilizable elements, genomic islands and insertion sequences. Some of the accessory functions associated to these MGEs have been linked previously to the flexible gene pool in microorganisms inhabiting completely different econiches. Yet, others had not been unambiguously mapped to the flexible gene pool prior to this report and clearly reflect strain-specific adaption to local environmental conditions. Significance: For many years, and because of DNA instability at low pH and recurrent failure to genetically transform acidophilic bacteria, gene transfer in acidic environments was considered negligible. Findings presented herein imply that a more or less conserved pool of actively excising MGEs occurs in the A. caldus population and point to a greater frequency of gene exchange in this econiche than previously recognized. Also, the data suggest that these elements endow the species with capacities to withstand the diverse abiotic and biotic stresses of natural environments, in particular those associated with its extreme econiche.

  • 4.
    Adolfsson Jörby, Sofie
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Local Agenda 21 in practice: a Swedish example2000In: Sustainable Development, ISSN 0968-0802, Vol. 8, no 4, p. 201-214Article in journal (Refereed)
  • 5.
    Aeinehband, Shahin
    et al.
    Karolinska Institutet.
    Lindblom, Rickard P. F.
    Karolinska Institutet.
    Al Nimer, Faiez
    Karolinska Institutet.
    Vijayaraghavan, Swetha
    Karolinska Institutet.
    Sandholm, Kerstin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Khademi, Mohsen
    Karolinska Institutet.
    Olsson, Tomas
    Karolinska Institutet.
    Nilsson, Bo
    Uppsala University.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Uppsala University.
    Darreh-Shori, Taher
    Karolinska Institutet.
    Piehl, Fredrik
    Karolinska Institutet.
    Complement Component C3 and Butyrylcholinesterase Activity Are Associated with Neurodegeneration and Clinical Disability in Multiple Sclerosis2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 4, article id e0122048Article in journal (Refereed)
    Abstract [en]

    Dysregulation of the complement system is evident in many CNS diseases but mechanisms regulating complement activation in the CNS remain unclear. In a recent large rat genomewide expression profiling and linkage analysis we found co-regulation of complement C3 immediately downstream of butyrylcholinesterase (BuChE), an enzyme hydrolyzing acetylcholine (ACh), a classical neurotransmitter with immunoregulatory effects. We here determined levels of neurofilament-light (NFL), a marker for ongoing nerve injury, C3 and activity of the two main ACh hydrolyzing enzymes, acetylcholinesterase (AChE) and BuChE, in cerebrospinal fluid (CSF) from patients with MS (n = 48) and non-inflammatory controls (n = 18). C3 levels were elevated in MS patients compared to controls and correlated both to disability and NFL. C3 levels were not induced by relapses, but were increased in patients with >= 9 cerebral lesions on magnetic resonance imaging and in patients with progressive disease. BuChE activity did not differ at the group level, but was correlated to both C3 and NFL levels in individual samples. In conclusion, we show that CSF C3 correlates both to a marker for ongoing nerve injury and degree of disease disability. Moreover, our results also suggest a potential link between intrathecal cholinergic activity and complement activation. These results motivate further efforts directed at elucidating the regulation and effector functions of the complement system in MS, and its relation to cholinergic tone.

  • 6.
    Aguirre-Gutierrez, Jesus
    et al.
    Naturalis Biodivers Ctr, Netherlands ; Univ Oxford, UK ; Univ Amsterdam, Netherlands.
    WallisDeVries, Michiel F.
    De Vlinderstichting, Netherlands ; Wageningen Univ, Netherlands.
    Marshall, Leon
    Naturalis Biodivers Ctr, Netherlands ; Univ Namur, Belgium.
    van't Zelfde, Maarten
    Naturalis Biodivers Ctr, Netherlands ; Leiden Univ, Netherlands.
    Villalobos-Arambula, Alma R.
    Univ Guadalajara, Mexico.
    Boekelo, Bastiaen
    Wageningen Univ & Res, Netherlands.
    Bartholomeus, Harm
    Wageningen Univ & Res, Netherlands.
    Franzén, Markus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. UFZ, Helmholtz Ctr Environm Res, Germany.
    Biesmeijer, Jacobus C.
    Naturalis Biodivers Ctr, Netherlands ; Leiden Univ, Netherlands.
    Butterflies show different functional and species diversity in relationship to vegetation structure and land use2017In: Global Ecology and Biogeography, ISSN 1466-822X, E-ISSN 1466-8238, Vol. 26, no 10, p. 1126-1137Article in journal (Refereed)
    Abstract [en]

    AimBiodiversity is rapidly disappearing at local and global scales also affecting the functional diversity of ecosystems. We aimed to assess whether functional diversity was correlated with species diversity and whether both were affected by similar land use and vegetation structure drivers. Better understanding of these relationships will allow us to improve our predictions regarding the effects of future changes in land use on ecosystem functions and services. LocationThe Netherlands. MethodsWe compiled a dataset of c.3 million observations of 66 out of 106 known Dutch butterfly species collected across 6,075 sampling locations during a period of 7 years, together with very high-resolution maps of land use and countrywide vegetation structure data. Using a mixed-effects modelling framework, we investigated the relationship between functional and species diversity and their main land use and vegetation structure drivers. ResultsWe found that high species diversity does not translate into high functional diversity, as shown by their different spatial distribution patterns in the landscape. Functional and species diversity are mainly driven by different sets of structural and land use parameters (especially average vegetation height, amount of vegetation between 0.5 and 2m, natural grassland, sandy soils vegetation, marsh vegetation and urban areas). We showed that it is a combination of both vegetation structural characteristics and land use variables that defines functional and species diversity. Main conclusionsFunctional diversity and species diversity of butterflies are not consistently correlated and must therefore be treated separately. High functional diversity levels occurred even in areas with low species diversity. Thus, conservation actions may differ depending on whether the focus is on conservation of high functional diversity or high species diversity. A more integrative analysis of biodiversity at both species and trait levels is needed to infer the full effects of environmental change on ecosystem functioning.

  • 7.
    Aguirre-Gutiérrez, Jesús
    et al.
    Naturalis Biodiversity Center, The Netherlands ; University of Amsterdam, The Netherlands.
    Kissling, W. Daniel
    University of Amsterdam, The Netherlands.
    Carvalheiro, Luísa G.
    Universidade de Brasília, Brazil ; University of Lisbon, Portugal.
    WallisDeVries, Michiel F.
    Wageningen University, The Netherlands.
    Franzén, Markus
    Helmholtz-Centre for Environmental Research - UFZ, Germany.
    Biesmeijer, Jacobus C.
    Naturalis Biodiversity Center, The Netherlands ; University of Amsterdam, The Netherlands.
    Functional traits help to explain half-century long shifts in pollinator distributions2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 24451Article in journal (Refereed)
    Abstract [en]

    Changes in climate and land use can have important impacts on biodiversity. Species respond to such environmental modifications by adapting to new conditions or by shifting their geographic distributions towards more suitable areas. The latter might be constrained by species’ functional traits that influence their ability to move, reproduce or establish. Here, we show that functional traits related to dispersal, reproduction, habitat use and diet have influenced how three pollinator groups (bees, butterflies and hoverflies) responded to changes in climate and land-use in the Netherlands since 1950. Across the three pollinator groups, we found pronounced areal range expansions (>53%) and modelled range shifts towards the north (all taxa: 17–22 km), west (bees: 14 km) and east (butterflies: 11 km). The importance of specific functional traits for explaining distributional changes varied among pollinator groups. Larval diet preferences (i.e. carnivorous vs. herbivorous/detritivorous and nitrogen values of host plants, respectively) were important for hoverflies and butterflies, adult body size for hoverflies, and flight period length for all groups. Moreover, interactions among multiple traits were important to explain species’ geographic range shifts, suggesting that taxon-specific multi-trait analyses are needed to predict how global change will affect biodiversity and ecosystem services.

  • 8.
    Akram, Neelam
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    From genes to ecological function in marine bacteria2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Bacteria in the sea are constantly exposed to environmental challenges (e.g. variations in nutrient concentrations, temperature and light conditions), and therefore appropriate gene expression response strategies to cope with them efficiently are evolved. This thesis investigates some interconnected questions regarding such adaptive strategies employed by marine bacteria.

    The recently discovered ability of bacteria to use the membrane protein proteorhodopsin (PR) to harvest light energy for cell metabolism were investigated in Vibrio sp. AND4 and Dokdonia sp. MED134. PR phototrophy in AND4 promoted survival during starvation, the molecular basis for which were the upregulation of the PR gene by nutrient limitation rather than light. MED134, in contrast, uses PR phototrophy to grow better, and we discovered that the light-stimulated growth was stronger in seawater with the single carbon compound alanine compared to a mixture of complex organic matter. Thus, differences between bacteria in PR gene expression regulation in response to light, nutrients or organic matter quality critically determine the ecological role of PR phototrophy in the sea.

    Current observations that membrane transporters (including PR) are highly expressed in seawater inspired a comparative analysis of transporter distributions in marine bacteria. Totally, 192 transporter families were found in 290 genome-sequenced strains. Consistent differences, but also similarities, in the number of transporters were found between major bacterial groups. Interestingly, sodium transporters were found to be more abundant in PR-containing SAR11. These findings suggest that bacteria have inherently distinctive potentials to adapt to resource variations in the sea.

    To examine links between transcriptional responses and growth of bacteria under controlled environmental settings, a mesocosm phytoplankton bloom experiment was performed. Transcriptional analysis of the microbial community (i.e. metatranscriptomics) revealed 2800 categories of functional genes (SEED functions), of which around 10% were overrepresented in either the bloom mesocosms or the controls. Importantly, these functions indicated potential metabolic mechanisms (e.g. TonB mediated nutrient transport) by which bacteria took advantage of the bloom conditions.

    This thesis combines analyses of model organisms with community analysis and highlights the possibilities to identify important mechanisms that underlie the ecological success of different bacteria in the marine environment. 

  • 9.
    Akram, Neelam
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Palovaara, Joakim
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Forsberg, Jeremy
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lindh, Markus V.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Milton, Debra L.
    Luo, Haiwei
    Gonzalez, Jose M.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Regulation of proteorhodopsin gene expression by nutrient limitation in the marine bacterium Vibrio sp AND42013In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 15, no 5, p. 1400-1415Article in journal (Refereed)
    Abstract [en]

    Proteorhodopsin (PR), a ubiquitous membrane photoprotein in marine environments, acts as a light-driven proton pump and can provide energy for bacterial cellular metabolism. However, knowledge of factors that regulate PR gene expression in different bacteria remains strongly limited. Here, experiments with Vibrio sp. AND4 showed that PR phototrophy promoted survival only in cells from stationary phase and not in actively growing cells. PR gene expression was tightly regulated, with very low values in exponential phase, a pronounced peak at the exponential/stationary phase intersection, and a marked decline in stationary phase. Thus, PR gene expression at the entry into stationary phase preceded, and could therefore largely explain, the stationary phase light-induced survival response in AND4. Further experiments revealed nutrient limitation, not light exposure, regulated this differential PR expression. Screening of available marine vibrios showed that the PR gene, and thus the potential for PR phototrophy, is found in at least three different clusters in the genus Vibrio. In an ecological context, our findings suggest that some PR-containing bacteria adapted to the exploitation of nutrient-rich micro-environments rely on a phase of relatively slowly declining resources to mount a cellular response preparing them for adverse conditions dispersed in the water column.

  • 10.
    Alatalo, Rauno V.
    et al.
    University of Jyväskylä, Finland.
    Eriksson, Dag
    Uppsala University, Sweden.
    Gustafsson, Lars
    Uppsala University, Sweden.
    Larsson, Kjell
    Uppsala University, Sweden.
    Exploitation competition influences the use of foraging sites by tits: Experimental evidence1987In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 68, no 2, p. 284-290Article in journal (Refereed)
    Abstract [en]

    In coniferous forests of central Sweden, tits (Paridae) and the Goldcrest, Regulus regulus, exploit nonrenewable resources in their group territories during winter. The smaller and socially subordinate species, the Goldcrest and the Coal Tit, Parus ater, forage on the outermost tree parts, while the larger and dominant Willow Tit, Parus montanus, and Crested Tit, Parus cristatus, forage on the inner tree parts. We removed Coal Tits and Goldcrests in three flocks in early winter to see if their absence would cause changes in the foraging patterns of the two dominant species. In late winter, Crested Tits foraged farther outward on branches of spruce in experimental flocks than they did in the control flocks. In spruce, Willow Tits foraged nearer the trunk than Crested Tits, and they did not respond to the experiment. In pine, Willow Tits, however, did move from branches to twigs in the absence of Coal Tits and Goldcrests. The experiment indicates that exploitation competition directly based on food depletion, without any interference, may influence the use of foraging sites by tits in coniferous forests.

  • 11.
    Albet-Torres, Nuria
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Månsson, Alf
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Long-Term Storage of Surface-Adsorbed Protein Machines2011In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 27, no 11, p. 7108-7112Article in journal (Refereed)
    Abstract [en]

    The effective and simple long-term storage of complex functional proteins is critical in achieving commercially viable biosensors. This issue is particularly challenging in recently proposed types of nanobiosensors, where molecular-motor-driven transportation substitutes microfluidics and forms the basis for novel detection schemes. Importantly, therefore, we here describe that delicate heavy meromyosin (HMM)-based nanodevices (HMM motor fragments adsorbed to silanized surfaces and actin bound to HMM) fully maintain their function when stored at -20 degrees C for more than a month. The mechanisms for the excellent preservation of acto-HMM motor function upon repeated freeze thaw cycles are discussed. The results are important to the future commercial implementation of motor-based nanodevices and are of more general value to the long-term storage of any protein-based bionanodevice.

  • 12. Alder, V A
    et al.
    Cuzin-Roudy, J
    Fransz, G
    Granéli, Edna
    Department of Marine Ecology, University of Lund .
    Larsen, J
    Rabbani, M M
    Thomsen, H
    Macro- and micrograzing effects on phytoplankton communities1989In: The expedition Antarktis VII/3 (EPOS LEG 2) of RV "Polarstern" in 1988/89 / [ed] I. Hempel, P.H. Schalk and V. Smetacek, Bremerhaven: Alfred- Wegener-Institut für Polar Meeresforschung , 1989, p. 123-130Chapter in book (Other academic)
  • 13.
    Alfredsson, Hanna
    University of Kalmar, School of Pure and Applied Natural Sciences. University of Kalmar, School of Pure and Applied Natural Sciences.
    Prey selection of European eel (Anguilla anguilla) larvae in the Sargasso Sea: a molecular approach.2009Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Abstract

    The European eel (Anguilla anguilla) migrates to the Sargasso Sea to spawn. Even though the biology of A. anguilla leptocephali in the Sargasso Sea has been studied for several decades, information regarding their diet has remained unknown until now. Previous dietary studies concerning other species of leptocephali in the Pacific Ocean have been limited to the recognition of identifiable prey remains amongst gut contents. Hence, in this study a molecular approach relying on the detection of prey DNA amongst gut contents was used to study dietary profiles of A. anguilla leptocephali in the Sargasso Sea.

     

    Leptocephali were collected during the circumglobal Galathea 3 expedition in spring 2007 to the Sargasso Sea. DNA extracted from gut contents were PCR amplified using universal primers targeting the nuclear 18S rRNA gene. In order to separate eel amplicons from prey amplicons, PCR products were analyzed by denaturing gradient gel electrophoresis (DGGE). Furthermore, clone libraries were constructed using universal primers targeting a portion of the 18S rRNA and mitochondrial COI gene, respectively. In total, the gut contents of 78 leptocephali were screened by DGGE.

     

    A diverse array of eukaryotic taxa was identified, hence demonstrating the applicability of a universal PCR- DGGE approach to study gut contents of leptocephali. The results presented here show, for the first time, that young stages of A. anguilla leptocephali feed on a large variety of zooplankton of which many were gelatinous (e.g. Hydrozoa, Thaliacea and Ctenophora). Several of the identified taxa also constitute important parts of the Sargasso Sea zooplankton community and are of size ranges (adult or larval stages) that made them reasonable as leptocephali prey.

  • 14.
    Almqvist, Maria
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Vanvårdens inverkan på nötkreaturs välfärd och hälsa2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Farmers are required to make sure that cattles basic needs are met, but still every year cases of neglect occur where the farmer has not complied within the animal welfare law and regulations. The aim of this study was to investigate how cattle are affected physically and behaviourally by neglect in the form of underfeeding, starvation and lack of sanitation, which animals are most vulnerable to the impact and what prospects they have to recover. The study was conducted as a literature study and the results show that these types of neglect have a large impact on the cattle welfare. Underfeeding and starvation causes physical changes leading to reduced milk production, reduced muscle mass, impaired immune function, poor reproductive performance and changes in rumen microflora leading to decreased number of microbes and pH change. Physical changes due to the lack of sanitation consist of increased vulnerability to hoof diseases and mastitis, burns, and increased sensitivity to temperature. The behaviourally changes that occur because of underfeeding and starvation include changes in eating habits, reduced lying time and reduced sleeping time. Insufficient sanitation cause behavioural changes including changes in laying time, increased agression, and slower movement. Pregnant cows and cows at peak lactation are sensitive to underfeeding and starvation, but also calves. Cattle kept in groups are most at risk for being contaminated. If the neglect is not too severe or prolonged, recovery can take place but in more serious cases of neglect, there is danger of the cattle’s life.

  • 15. Alonso-Saez, L.
    et al.
    Vazquez-Dominguez, E.
    Cardelus, C.
    Pinhassi, Jarone
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Sala, M. M.
    Lekunberri, I.
    Balague, V.
    Vila-Costa, M.
    Unrein, F.
    Massana, R.
    Simo, R.
    Gasol, J. M.
    Factors controlling the year-round variability in carbon flux through bacteria in a coastal marine system2008In: Ecosystems (New York. Print), ISSN 1432-9840, E-ISSN 1435-0629, Vol. 11, no 3, p. 397-409Article in journal (Refereed)
    Abstract [en]

    Data from several years of monthly samplings are combined with a 1-year detailed study of carbon flux through bacteria at a NW Mediterranean coastal site to delineate the bacterial role in carbon use and to assess whether environmental factors or bacterial assemblage composition affected the in situ rates of bacterial carbon processing. Leucine (Leu) uptake rates [as an estimate of bacterial heterotrophic production (BHP)] showed high interannual variability but, on average, lower values were found in winter (around 50 pM Leu(-1) h(-1)) as compared to summer (around 150 pM Leu(-1) h(-1)). Leu-to-carbon conversion factors ranged from 0.9 to 3.6 kgC mol Leu(-1), with generally higher values in winter. Leu uptake was only weakly correlated to temperature, and over a full-year cycle (in 2003), Leu uptake peaked concomitantly with winter chlorophyll a (Chl a) maxima, and in periods of high ectoenzyme activities in spring and summer. This suggests that both low molecular weight dissolved organic matter (DOM) released by phytoplankton, and high molecular weight DOM in periods of low Chl a, can enhance BHP. Bacterial respiration (BR, range 7-48 mu g C l(-1) d(-1)) was not correlated to BHP or temperature, but was significantly correlated to DOC concentration. Total bacterial carbon demand (BHP plus BR) was only met by dissolved organic carbon produced by phytoplankton during the winter period. We measured bacterial growth efficiencies by the short-term and the long-term methods and they ranged from 3 to 42%, increasing during the phytoplankton blooms in winter (during the Chl a peaks), and in spring. Changes in bacterioplankton assemblage structure (as depicted by denaturing gradient gel electrophoresis fingerprinting) were not coupled to changes in ecosystem functioning, at least in bacterial carbon use.

  • 16. Alonso-Saez, Laura
    et al.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Pernthaler, Jakob
    Gasol, Josep M.
    Leucine-to-carbon empirical conversion factor experiments: does bacterial community structure have an influence?2010In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 12, no 11, p. 2988-2997Article in journal (Refereed)
    Abstract [en]

    The suitability of applying empirical conversion factors (eCFs) to determine bacterial biomass production remains unclear because seawater cultures are usually overtaken by phylotypes that are not abundant in situ. While eCFs vary across environments, it has not been tested whether differences in eCFs are driven by changes in bacterial community composition or by in situ environmental conditions. We carried out seawater cultures throughout a year to analyse the correlation between eCFs and bacterial community structure, analysed by catalysed reporter deposition fluorescence in situ hybridization. Gammaproteobacteria usually dominated seawater cultures, but their abundance exhibited a wide range (25–73% of cell counts) and significantly increased with inorganic nutrient enrichment. Flavobacteria were less abundant but increased up to 40% of cells counts in winter seawater cultures, when in situ chlorophyll a was high. The correlations between eCFs and the abundance of the main broad phylogenetic groups (Gamma-, Alphaproteobacteria and Flavobacteria) were significant, albeit weak, while more specific groups (Alteromonadaceae and Rhodobacteraceae) were not significantly correlated. Our results show that the frequent development of the fast-growing group Alteromonadaceae in seawater cultures does not strongly drive the observed variations in eCFs. Rather, the results imply that environmental conditions and the growth of specific phylotypes interact to determine eCFs.

  • 17. Alonso-Saéz, Laura
    et al.
    Waller, Allison S
    Mende, Daniel R
    Bakker, Kevin
    Farnelid, Hanna
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Yager, Patricia L
    Lovejoy, Connie
    Tremblay, Jean-Eric
    Potvin, Marianne
    Heinrich, Friederike
    Estrada, Marta
    Riemann, Lasse
    Marine Biological Section, University of Copenhagen, 3000 Helsingør, Denmark .
    Bork, Peer
    Pedros-Alio, Carlos
    Bertilsson, Stefan
    Role for urea in nitrification by polar marine Archaea2012In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, no 44, p. 17989-17994Article in journal (Refereed)
    Abstract [en]

    Despite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity of Thaumarchaeota in polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth. Thaumarchaeota were more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5% Thaumarchaeota cells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed that Thaumarchaeota had pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polar Thaumarchaeota had the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification. Thaumarchaeota from Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway for Thaumarchaeota and other microorganisms exposed to the low-energy conditions of dark polar waters.

  • 18.
    Alvunger, David
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Variation in number of vertebrae in populations of pike (Esox lucius) in the south-east of Sweden2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vertebral number (VN) is known to vary greatly across different taxa, but also within species orpopulations. Extensive research has shown that VN in fish is the result of interactions between geneticstructure and plastic responses to environmental cues during ontogeny. A frequently reported pattern is the tendency for VN to vary with body shape and/or length of the fish. The pike (Esox lucius) of the Baltic Sea has a complex population structure, with genetically distinct subpopulations consisting of homing anadromous individuals. Individuals belonging to these subpopulations are sympatric for most of their lives and become allopatric briefly during spawning each year. This study examined the distribution of VN in three anadromous sympatric subpopulations of pike in the Baltic. Significant differences in VN were found between juveniles and adults belonging to different subpopulations, but also across life-stageswithin all three subpopulations. Results from a common-garden experiment indicated that differences in VN among subpopulations were in part the result of genetic differences, indicative of evolutionary change. Furthermore, a quadratic regression revealed a curvilinear relationship between VN and bodylength of juveniles. Taken together, these results suggest that the combined effects of stabilizing and divergent selection might have played a role in shaping the distribution of VN in pike of the Baltic. The distribution of VN within subpopulations seems to be under the influence of stabilizing selection. Differences among subpopulations might instead reflect local adaptations driven by divergent selection. These findings signal the need for conservationists to view these subpopulations as unique units of management.

  • 19. Ammerman, J.W.
    et al.
    Fuhrman, J.A.
    Hagström, Åke
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Azam, F.
    Bacterioplankton growth in seawater: I.Growth kinetics and cellular characteristics in seawater cultures1984In: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 18, p. 31-39Article in journal (Refereed)
  • 20.
    Amnebrink, Dennis
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Infection intensity and molecular characterization of eye flukes in round gobies (Neogobius melanostomus).2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The round goby (Neogobius melanostomus) is an invasive species to the Baltic Sea and is rapidly expanding its range. Apart from competition with native fish, a novel species may face, or introduce, pathogens. Previous research has shown that round gobies have a high infection rate by eye flukes of the Diplostomum genus. To study prevalence and infection intensity of Diplostomum parasites in fish in an area recently colonized by round gobies, the shallow water community of round goby, common bleak (Alburnus alburnus) and three-spined stickleback (Gasterosteus aculeatus) was examined. The fish were screened for presence of parasites in the lenses of caught fish, and abundance of parasites was compared between the host species. The round goby had the highest infection intensity of the host species, and there was no difference in infection intensity between the common bleak and three spined stickleback. To support microscopy-based identification, the parasites from the round gobies were determined to genus/species level using molecular detection and sequencing, enabling a Diplostomum species composition inventory in round gobies. Results showed that at least three species of Diplostomum infected round gobies in this population, and that there was a negative correlation between body condition and the parasite intensity indicating fitness effects resulting from infection.

  • 21.
    Anderholm, Sofia
    et al.
    University of Gothenburg.
    Marshall, Rupert C
    Aberystwyth University, UK.
    van der Jeugd, Henk P
    SOVON Dutch Centre for Field Ornithology, The Netherlands ; Vogeltrekstation Dutch Centre for Avian Migration and Demography, The Netherlands.
    Waldeck, Peter
    University of Gothenburg.
    Larsson, Kjell
    Gotland University.
    Andersson, Malte
    University of Gothenburg.
    Nest parasitism in the barnacle goose: evidence from protein fingerprinting and microsatellites2009In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 78, no 1, p. 167-174Article in journal (Refereed)
    Abstract [en]

    Geese are often seen as one of nature's best examples of monogamous relationships, and many social pairs stay together for life. However, when parents and young are screened genetically, some chicks do not match their social parents. Although this has often been explained as adoption of foreign young after hatching, conspecific nest parasitism is another possibility. We used nondestructive egg albumen sampling and protein fingerprinting to estimate the frequency and success of nest parasitism in a Baltic Sea population of barnacle geese, Branta leucopsis. Among the 86 nests for which we had the most complete information, 36% were parasitized, and 12% of the eggs were parasitic. Almost 80% of the parasitic eggs were laid after the host began incubation. Hatching of these eggs was limited to the few cases where the host female incubated longer than normally because her own eggs failed to hatch. Conspecific nest parasitism in this population therefore seems mainly to be an alternative reproductive tactic of lower fitness than normal nesting. Comparison with DNA profiling of chicks (with 10–14 microsatellites) and other evidence confirmed the suitability of protein fingerprinting for analysis of nest parasitism. It can often provide more data than microsatellites, if eggs are albumen-sampled soon after being laid, before most losses occur.

  • 22.
    Anderholm, Sofia
    et al.
    University of Gothenburg.
    Waldeck, Peter
    University of Gothenburg.
    van der Jeugd, Henk P
    Netherlands Institute for Ecology (NIOO-KNAW), The Netherlands.
    Marshall, Rupert C
    University of Gothenburg ; Aberystwyth University, UK.
    Larsson, Kjell
    Gotland University.
    Andersson, Malte
    University of Gothenburg.
    Colony kin structure and host-parasite relatedness in the barnacle goose2009In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 18, no 23, p. 4955-4963Article in journal (Refereed)
    Abstract [en]

    Conspecific brood parasitism (CBP), females laying eggs in the nest of other 'host' females of the same species, is a common alternative reproductive tactic among birds. For hosts there are likely costs of incubating and rearing foreign offspring, but costs may be low in species with precocial chicks such as waterfowl, among which CBP is common. Waterfowl show strong female natal philopatry, and spatial relatedness among females may influence the evolution of CBP. Here we investigate fine-scale kin structure in a Baltic colony of barnacle geese, Branta leucopsis, estimating female spatial relatedness using protein fingerprints of egg albumen, and testing the performance of this estimator in known mother-daughter pairs. Relatedness was significantly higher between neighbour females (nesting ≤ 40 metres from each other) than between females nesting farther apart, but there was no further distance trend in relatedness. This pattern may be explained by earlier observations of females nesting close to their mother or brood sisters, even when far from the birth nest. Hosts and parasites were on average not more closely related than neighbour females. In 25 of 35 sampled parasitized nests, parasitic eggs were laid after the host female finished laying, too late to develop and hatch. Timely parasites, laying eggs in the host's laying sequence, had similar relatedness to hosts as that between neighbours. Females laying late parasitic eggs tended to be less related to the host, but not significantly so. Our results suggest that CBP in barnacle geese might represent different tactical life-history responses.

  • 23.
    Andersen, K. H.
    et al.
    Tech Univ Denmark, Denmark.
    Berge, T.
    Tech Univ Denmark, Denmark ; Univ Copenhagen, Denmark.
    Goncalves, R. J.
    Tech Univ Denmark, Denmark ;Consejo Nacl Invest Cient & Tecn, Argentina ; Estn Fotobiol Playa Union, Argentina.
    Hartvig, M.
    Tech Univ Denmark, Denmark ; Univ Copenhagen, Denmark ; Univ Göttingen, Germany.
    Heuschele, J.
    Tech Univ Denmark, Denmark.
    Hylander, Samuel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Tech Univ Denmark, Denmark.
    Jacobsen, N. S.
    Tech Univ Denmark, Denmark.
    Lindemann, C.
    Tech Univ Denmark, Denmark.
    Martens, E. A.
    Tech Univ Denmark, Denmark ; Univ Copenhagen, Denmark.
    Neuheimer, A. B.
    Tech Univ Denmark, Denmark ; Univ Hawaii Manoa, USA.
    Olsson, K.
    Tech Univ Denmark, Denmark.
    Palacz, A.
    Tech Univ Denmark, Denmark.
    Prowe, A. E. F.
    Tech Univ Denmark, Denmark ; GEOMAR Helmholtz Ctr Ocean Res Kiel, Germany.
    Sainmont, J.
    Tech Univ Denmark, Denmark.
    Traving, S. J.
    Tech Univ Denmark, Denmark ; Univ Copenhagen, Denmark.
    Visser, A. W.
    Tech Univ Denmark, Denmark.
    Wadhwa, N.
    Tech Univ Denmark, Denmark.
    Kiorboe, T.
    Tech Univ Denmark, Denmark.
    Characteristic Sizes of Life in the Oceans, from Bacteria to Whales2016In: Annual Review of Marine Science, ISSN 1941-1405, E-ISSN 1941-0611, Vol. 8, p. 217-241Article in journal (Refereed)
    Abstract [en]

    The size of an individual organism is a key trait to characterize its physiology and feeding ecology. Size-based scaling laws may have a limited size range of validity or undergo a transition from one scaling exponent to another at some characteristic size. We collate and review data on size-based scaling laws for resource acquisition, mobility, sensory range, and progeny size for all pelagic marine life, from bacteria to whales. Further, we review and develop simple theoretical arguments for observed scaling laws and the characteristic sizes of a change or breakdown of power laws. We divide life in the ocean into seven major realms based on trophic strategy, physiology, and life history strategy. Such a categorization represents a move away from a taxonomically oriented description toward a trait-based description of life in the oceans. Finally, we discuss life forms that transgress the simple size-based rules and identify unanswered questions.

  • 24.
    Andersson, A.
    et al.
    Umeå University;Umeå Marine Science Centre.
    Brugel, S.
    Umeå University;Umeå Marine Science Centre.
    Paczkowska, J.
    Umeå University;Umeå Marine Science Centre.
    Rowe, O. F.
    Umeå University;Umeå Marine Science Centre;Univ Helsinki, Finland.
    Figueroa, D.
    Umeå University;Umeå Marine Science Centre.
    Kratzer, S.
    Stockholm University.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Influence of allochthonous dissolved organic matter on pelagic basal production in a northerly estuary2018In: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 204, p. 225-235Article in journal (Refereed)
    Abstract [en]

    Phytoplankton and heterotrophic bacteria are key groups at the base of aquatic food webs. In estuaries receiving riverine water with a high content of coloured allochthonous dissolved organic matter (ADOM), phytoplankton primary production may be reduced, while bacterial production is favoured. We tested this hypothesis by performing a field study in a northerly estuary receiving nutrient-poor, ADOM-rich riverine water, and analyzing results using multivariate statistics. Throughout the productive season, and especially during the spring river flush, the production and growth rate of heterotrophic bacteria were stimulated by the riverine inflow of dissolved organic carbon (DOC). In contrast, primary production and photosynthetic efficiency (i.e. phytoplankton growth rate) were negatively affected by DOC. Primary production related positively to phosphorus, which is the limiting nutrient in the area. In the upper estuary where DOC concentrations were the highest, the heterotrophic bacterial production constituted almost 100% of the basal production (sum of primary and bacterial production) during spring, while during summer the primary and bacterial production were approximately equal. Our study shows that riverine DOC had a strong negative influence on coastal phytoplankton production, likely due to light attenuation. On the other hand DOC showed a positive influence on bacterial production since it represents a supplementary food source. Thus, in boreal regions where climate change will cause increased river inflow to coastal waters, the balance between phytoplankton and bacterial production is likely to be changed, favouring bacteria. The pelagic food web structure and overall productivity will in turn be altered. (C) 2018 The Authors. Published by Elsevier Ltd.

  • 25. Andersson, A.
    et al.
    Falk, S.
    Samuelsson, G.
    Hagström, Åke
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nutritional characteristics of a mixitropic nanoflagellate, Ochromonas sp.1989In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 17, p. 117-128Article in journal (Refereed)
  • 26.
    Andersson, Agneta
    et al.
    Department of Microbiology. University of Urnea. S-901 87 UMEA, Sweden.
    Lee, C.
    Azam, F.
    Hagström, Åke
    Department of Microbiology. University of Urnea. S-901 87 UMEA, Sweden.
    Release of aminoacids and inorganic nutrients by heterotrophic marine microflagellates1985In: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 23, p. 99-106Article in journal (Refereed)
    Abstract [en]

    Heterotrophic microflagellates isolated from the Baltic Sea and grown under laboratoryconditions were shown to release dissolved free amino acids (DFAA) when grazing bacteria. Flagellatesreleased 3H-amino acids when fed 3H-leucine-labelled bacteria, and concentrations of aminoacids increased in the experimental medium. Serine showed a strong positive correlation withflagellate feeding. Aspartic acid, glutamic acid and ornithine also increased more than other aminoacids. During consumption of bacteria, the flagellates released 13% of the ingested nitrogen asammonia, and 30 % of the ingested phosphorus as phosphate. In a field experiment off Scripps Pier, wemeasured bacterial production, flagellate abundance, and concentration of DFAA over a 28 h period.The concentration of DFAA showed a covariation with the flagellate numbers. Results from our fieldand laboratory experiments suggest that flagellates may be a source of DFAA in the sea. 

  • 27. Andersson, Anders F.
    et al.
    Riemann, Lasse
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bertilsson, Stefan
    Pyrosequencing reveals contrasting seasonal dynamics of taxa within Baltic Sea bacterioplankton communities2010In: The ISME Journal, ISSN 1751-7362, E-ISSN 1751-7370, l, Vol. 4, p. 171-181Article in journal (Refereed)
    Abstract [en]

    Variation in traits causes bacterial populations to respond in contrasting ways to environmental drivers. Learning about this will help us understand the ecology of individual populations in complex ecosystems. We used 454 pyrosequencing of the hypervariable region V6 of the 16S rRNA gene to study seasonal dynamics in Baltic Sea bacterioplankton communities, and link community and population changes to biological and chemical factors. Surface samples were collected from May to October 2003 and in May 2004 at the Landsort Deep in the central Baltic Sea Proper. The analysis rendered, on average, 20 200 sequence reads for each of the eight samples analyzed, providing the first detailed description of Baltic Sea bacterial communities. Community composition varied dramatically over time, supporting the idea of strong temporal shifts in bacterioplankton assemblages, and clustered according to season (including two May samples from consecutive years), suggesting repeatable seasonal succession. Overall, community change was most highly correlated with change in phosphorus concentration and temperature. Individual bacterial populations were also identified that tightly co-varied with different Cyanobacteria populations. Comparing the abundance profiles of operational taxonomic units at different phylogenetic distances revealed a weak but significant negative correlation between abundance profile similarity and genetic distance, potentially reflecting habitat filtering of evolutionarily conserved functional traits in the studied bacterioplankton.

  • 28.
    Andersson, Håkan S.
    University of Kalmar, School of Pure and Applied Natural Sciences. Lund University, Sweden.
    On the Nature and Origin of Recognition in Molecularly Imprinted Polymers.: Paths Towards Their Rational Design.1997Licentiate thesis, monograph (Other academic)
  • 29.
    Andersson, Håkan S.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Towards the Rational Design of Molecularly Imprinted Polymers1999Doctoral thesis, comprehensive summary (Other academic)
  • 30.
    Andersson, Håkan S.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Jacobsson, Erik
    Uppsala University.
    Eriksson, Camilla
    Uppsala University.
    Hedström, Martin
    Lund University.
    Seth, Henrik
    University of Gothenburg.
    Sundberg, Per
    University of Gothenburg.
    Rosengren, Johan
    University of Queensland.
    Strand, Malin
    Swedish University of Agricultural Sciences.
    Göransson, Ulf
    Uppsala University.
    The toxicity of ribbon worms: alpha-nemertides or tetrodotoxin, or both?2016In: Planta Medica, ISSN 0032-0943, E-ISSN 1439-0221, Vol. 82, no Supplement 1, article id P549Article in journal (Other academic)
    Abstract [en]

    The marine ribbon worms (nemerteans) are predators which capture their prey by everting a proboscis carrying a mixture of toxins which brings on rapid paralysis [1]. Moreover, ribbon worms have a thick layer of epidermal mucus of similar constitution. Tetrodotoxin (TTX) has been identified as one of these toxins [2]. The extreme toxicity of TTX (lethal by ingestion of 0.5-2 mg) is due to its ability to block voltage-gated sodium channels. Although several bacterial species (among these Vibrio sp.) have been linked to its synthesis, the biogenic origin and biosynthesis is unclear. One hypothesis is that TTX production occurs in a symbiotic relationship with its host, in this case the ribbon worm [3]. We have made significant effort to identify TTX in a setup for production through the cultivation of Vibrio alginolyticus in nutrient broth infused with mucus from the ribbon worm Lineus longissimus. Toxicity was demonstrated by fraction injections into shore crabs, but no TTX was found, and it could be shown conclusively that toxicity was unrelated to TTX and the Vibrio culture itself, and rather a constituent of the ribbon worm mucus [4]. The following studies led us to the discovery of a new class of peptides, the alpha-nemertides, in the mucus of the ribbon worms, which could be directly linked to the toxic effects. A literature review of the available evidence for TTX in ribbon worms show that the evidence in most cases are indirect, although notable exceptions exist. This points to the necessity to further investigate the presence and roles of TTX and alpha-nemertides in ribbon worms.

  • 31.
    Andersson, Håkan S.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Jacobsson, Erik
    Uppsala University.
    Rosengren, Johan
    University of Queensland, Australia.
    Strand, Malin
    Swedish University of Agricultural Sciences.
    Göransson, Ulf
    Uppsala University.
    Discovery of novel ion-channel active peptide toxins in a North Sea Ribbon Worm2016Conference paper (Other academic)
    Abstract [en]

    Ribbon worms (nemerteans) are marine predators, which capture their prey using a proboscis containing a mixture of toxins which brings on rapid paralysis [1]. In addition, their epidermis contains thick mucus of similar toxic constitution. One very potent toxin reported in ribbon worm mucus is tetrodotoxin (TTX). However, despite significant efforts, Strand et al. [2] were unable to detect any TTX, neither in the mucus of the ribbon worm Lineus longissimus, nor from Vibrio alginolyticus cultures isolated from and cultivated in the mucus. These observations challenged the notion of general presence of TTX in ribbon worm mucus, and prompted us to look for other toxins [3]. Using LC-MS analysis of mucus extracts, we identified three peptides present in significant amounts. The peptides were sequenced using a combination of MS/MS analysis and transcriptomics, and whereas one of them strongly resembles the only peptide toxin previously characterized from ribbon worms, Neurotoxin B-IV [4], the other two were found to represent a previously unknown class of peptide toxins. The most abundant of these was synthesized, and its 3D structure determined. Preliminary toxicity tests on shore crab (C. maenas) indicated toxicity (through paralysis) on par with that of TTX. Further analyses have indicated that its toxic effects are due to binding to voltage sensitive sodium channels.

     

    With L. longissimus as our primary target, we are now mapping the presence of peptide toxins in ribbon worms, with the objectives to establish routes for synthesis, and to characterize the biological activities and structures of these peptides. The number of peptides of this novel class is increasing, and synthesis and characterization is well underway. The striking potencies of these peptides make them potentially amenable as novel insecticidal or anthelmintic leads, pharmacological tools or in biotechnology applications.

     

    References

    1. Strand M, Sundberg P. Nationalnyckeln till Sveriges flora och fauna [DO-DP]. Stjärnmaskar-Slemmaskar: Sipuncula-Nemertea: Artdatabanken, SLU; 2010.

    2. Strand M, Hedstrom M, Seth H, McEvoy EG, Jacobsson E, Goransson U, Andersson HS, Sundberg P. The Bacterial (Vibrio alginolyticus) Production of Tetrodotoxin in the Ribbon Worm Lineus longissimus-Just a False Positive? Marine Drugs. 2016;14(4).

    3. Strand M, Andersson HS. Slemmaskens hemlighet. Forskning & Framsteg. 2016;(2):26-33.

    4. Blumenthal KM, Kem WR. Structure and action of heteronemertine polypeptide toxins. Primary structure of Cerebratulus lacteus toxin B-IV. The Journal of Biological Chemistry. 1976;251(19):6025-9.

  • 32.
    Andersson, Håkan S.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Jacobsson, Erik
    Uppsala University.
    Strand, Malin
    Swedish agricultural university (SLU).
    Peigneur, Steve
    University of Leuven (KU Leuven), Belgium.
    Lebbe, Eline
    University of Leuven (KU Leuven), Belgium.
    Rosengren, Johan
    University of Queensland.
    Tytgat, Jan
    University of Leuven (KU Leuven), Belgium.
    Göransson, Ulf
    Uppsala University.
    Alpha-nemertides, a novel family of marine peptide neurotoxins from ribbon worms2017Conference paper (Other academic)
  • 33. Andersson, J.
    et al.
    Dahl, J.
    Johansson, A.
    Karås, P.
    Nilsson, J.
    Sandström, O.
    Svensson, P. Andreas
    Utslagen fiskrekrytering och sviktande fiskbestånd i Kalmar läns kustvatten. (English title: Recruitment failure and decreasing fish stocks in the coastal areas of Kalmarsund.)2000Report (Refereed)
  • 34.
    Andersson, Johan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Hantering av bränsleflis: Enkätundersökning och bedömning av kvalitetsaspekter2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Med globalt ökat klimathot och ett ökat användande av biologiskt nedbrytbara material för att bland annat driva vår motorpark och värma våra hus kommer även ett krav på ökat produktion av utsläppsreducerande (koldioxid CO2) material så som biobränsle.

    För att kunna reducera utsläppen krävs inte bara att vi ökar produktionen av biologiskt nedbrytbart ämnen utan att dessa material har de egenskaperna som de förbränningssystem de används till optimalt kräver.

    Ett av de biologiskt nedbrytbara materialen är biobränsle, framställt av skogsavfall (grot). Dess hantering ifrån avverkningstillfället tills in- transport till förbränningen har varit kärnan i detta arbete. De två grundfrågorna som har varit själva motorn i arbetet har kretsat kring;

    o Vem äger vad i olika hanteringssteg?

    o Vem vet vad i olika hanteringssteg?

    Syftet med denna undersökning var att bland annat försöka få reda på svaren på frågorna ovan men även att väcka ett ökat intresse och förståelse kring hanteringen av biobränslet från avverkningstillfället fram till in- transport till en terminal alternativt direkt in till panncentralen.

    Undersökningen gjordes genom en enkätundersökning på Internet. Enkäten skickades ut till berörda parter i Sverige per e-post och adressaterna kunde svara direkt i datorn och skicka tillbaka enkäten utan att skriva ut den. Svaren från Skåne i söder upp till Mälardalen i norr vilket gör att man kan säga att denna undersökning gäller för södra Sverige.

  • 35.
    Andersson, Kajsa
    Barometern OT.
    Forskningsprojekt: Alger ska rena utsläpp: "Algerna är en resurs som vi knappt använder"2014In: Baromtern, no 9 augustiArticle in journal (Other (popular science, discussion, etc.))
  • 36.
    Andersson, Lars
    et al.
    Swedish University of Agricultural Sciences, Department of Crop Production Ecology.
    Bostrom, Ullalena
    Swedish University of Agricultural Sciences, Department of Crop Production Ecology.
    Forkman, Johannes
    Swedish University of Agricultural Sciences, Department of Crop Production Ecology.
    Hakman, Inger
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Liew, Josefine
    Swedish University of Agricultural Sciences, Department of Crop Production Ecology.
    Magnuski, Ewa
    Swedish University of Agricultural Sciences, Department of Crop Production Ecology.
    Sprouting capacity from intact root systems of Cirsium arvense and Sonchus arvensis decrease in autumn2013In: Weed research (Print), ISSN 0043-1737, E-ISSN 1365-3180, Vol. 53, no 3, p. 183-191Article in journal (Refereed)
    Abstract [en]

    Perennial weeds are often controlled by mechanical means, which aim at stimulating axillary and adventitious buds to sprout. This happens when the apical dominance of the main shoot is removed by defoliation or when the underground system is fragmented. By repeating the measures, the result is a depletion of storage compounds, which weakens the plants and reduces their capacity to grow and reproduce. However, timing is critical. Earlier research has indicated that emergence from fragments of Sonchus arvensis cease during a period in autumn, while the seasonal pattern of sprouting in Cirsium arvense appears to be inconsistent. We studied the emergence pattern of defoliated plants with undisturbed root systems, from late summer to early spring. Potted plants grown outdoors were exhumed at regular intervals, put under forcing conditions for 4weeks, after which shoots above and below soil level were counted and weighed together with the remaining root systems. In both species, the number and weight of emerged shoots decreased during a period in the autumn. In C.arvense, underground shoots were constantly produced during the same period, while fewer underground shoots were present in S.arvensis. For the latter species, apical dominance does not fully explain the effect; thus, endodormancy might be involved. Root weight increased until withering and did not explain the lack of emergence. Our results suggest an impaired sprouting capacity of undisturbed root systems of C.arvense and S.arvensis during SeptemberOctober, which has implications for the timing and method of control of these species.

  • 37. Andersson, Lars
    et al.
    Boström, Ullalena
    Hakman, Inger
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Liew, Josefine
    Magnuski, Eva
    Milberg, Per
    SPROUTING CAPACITY OF UNDERGROUND LATERAL BUDS OF RHIZOMATEOUS PERENNIAL WEEDS VARY WITH SEASON2010Conference paper (Other academic)
  • 38.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Lund University.
    Bergvall, Ulrika A.
    Stockholm University ; Swedish University of Agricultural Sciences.
    Chirico, Jan
    National Veterinary Institute.
    Christensson, Madeleine
    Swedish University of Agricultural Sciences.
    Lindgren, Per-Eric
    Linköping University ; County Hospital Ryhov.
    Nordström, Jonas
    Swedish University of Agricultural Sciences ; Dalarna County Administration Board.
    Kjellander, Petter
    Swedish University of Agricultural Sciences.
    Molecular detection of Babesia capreoli and Babesia venatorum in wild Swedish roe deer, Capreolus capreolus2016In: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 9, article id 221Article in journal (Refereed)
    Abstract [en]

    Background: The epidemiology of the zoonotic tick-transmitted parasite Babesia spp. and its occurrence in wild reservoir hosts in Sweden is unclear. In European deer, several parasite species, including Babesia capreoli and the zoonotic B. venatorum and B. divergens has been reported previously. The European roe deer, Capreolus capreolus, is an important and common part of the indigenous fauna in Europe, as well as an important host for Ixodes ricinus ticks, the vector of several Babesia spp. in Europe. Here, we aimed to investigate the occurrence of Babesia spp. in roe deer in Sweden. Findings: Roe deer (n = 77) were caught and sampled for blood. Babesia spp. was detected with a PCR assay targeting the 18S rRNA gene. The prevalence of Babesia spp. was 52 %, and two species were detected; B. capreoli and B. venatorum in 44 and 7.8 % of the individuals, respectively. Infection occurred both in summer and winter. Conclusions: We showed that roe deer in Sweden, close to the edge of their northern inland distributional range, are infected with Babesia spp. The occurrence of B. venatorum in roe deer imply that it is established in Sweden and the zoonotic implication of this finding should be regarded to a greater extent in future.

  • 39.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Chitimia-Dobler, Lidia
    Inst Diag & Anim Hlth, Romania ; German Ctr Infect Res DZIF Partner Munich, Germany.
    Detection of Cercopithifilaria bainae in western Romania2017In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 116, no 11, p. 3235-3238Article in journal (Refereed)
    Abstract [en]

    Cercopithifilaria species are tick-transmitted filarial parasites of mammals. In Europe, three Cercopithifilaria spp. are known to parasitize dogs, all occurring mainly in the Mediterranean countries. In Romania, Cercopithifilaria bainae has been reported in a single dog in eastern Romania but the occurrence in other parts of the country is not known. To further elucidate the geographic distribution of Cercopithifilaria spp. infection, 544 ticks were collected from dogs in several locations across Romania. The presence of Cercopithifilaria spp. was investigated with real-time PCR. A single Dermacentor reticulatus female tick was found to be infected with Cercopithifilaria bainae. The finding in the present study is geographically separated from the previous finding in Romania by 800 km, as well as by the Carpathian mountain range. Hence, C. bainae is more geographically widespread in Romania than previously recognized. However, the single detection does suggest that infection is rather uncommon in Romanian dogs. Nevertheless, further studies on Cercopithifilaria spp. distribution and prevalence are needed.

  • 40.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Marga, Georgeta
    Publ Hlth Direct, Romania.
    Banu, Teofilia
    Inst Diag & Anim Hlth, Romania.
    Dobler, Gerhard
    German Ctr Infect Res DZIF Partner Munich, Germany.
    Chitimia-Dobler, Lidia
    Inst Diag & Anim Hlth, Romania;German Ctr Infect Res DZIF Partner Munich, Germany.
    Tick-borne pathogens in tick species infesting humans in Sibiu County, central Romania2018In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 117, no 5, p. 1591-1597Article in journal (Refereed)
    Abstract [en]

    Romania has a highly diverse tick fauna. Consequently, a high diversity of tick-transmitted pathogens might be a potential threat to humans. However, only a limited number of tick species regularly infest humans, and pathogens present in such species are therefore of particular interest from a medical perspective. In this study, 297 ticks were collected from humans during 2013 and 2014. Ixodes ricinus was the predominant tick species, accounting for 272 specimens or 91.6% of the ticks in the study. Nevertheless, other tick species were also found to infest humans: Dermacentor marginatus constituted 7% of the ticks found on humans (21/297), Haemaphysalis punctata 1% (3/297), and Haemaphysalis concinna 0.3% (1/297). Ticks were tested by PCR for a wide range of tick-borne pathogens. In total, 11.8% of the ticks carried human pathogenic bacteria, while no viral or protozoan pathogens were detected. The most frequently detected pathogen was Rickettsia spp., occurring in 5.4% of the ticks (16/297) and comprising three species: Rickettsia (R.) raoultii, R. monacensis, and R. helvetica. Borrelia s.l. occurred in 3% (9/297) of the ticks. "Candidatus Neoehrlichia mikurensis" occurred in 1.7% (5/297) and Anaplasma phagocytophilum in 1.3% (4/297). Anaplasma bovis was detected in an H. punctata and Borrelia miyamotoi in an I. ricinus. These results point to the need for further studies on the medical importance of tick-borne pathogens in Romania.

  • 41.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Radbea, Gabriel
    Sal Vet Private Vet Clin, Romania.
    Frangoulidis, Dimitrios
    Bundeswehr Inst Microbiol, Germany;German Ctr Infect Res DZIF Partner Munich.
    Tomaso, Herbert
    Friedrich Loeffler Inst, Germany.
    Rubel, Franz
    Univ Vet Med Vienna, Austria.
    Nava, Santiago
    Estn Expt Agr Rafaela, Argentina.
    Chitimia-Dobler, Lidia
    Bundeswehr Inst Microbiol, Germany;German Ctr Infect Res DZIF Partner Munich, Germany;Inst Diag & Anim Hlth, Romania.
    New records and host associations of the tick Ixodes apronophorus and the first detection of Ehrlichia sp HF in Romania2018In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 117, no 4, p. 1285-1289Article in journal (Refereed)
    Abstract [en]

    Ixodes (Ixodes) apronophorus is a neglected tick species and its geographical distribution, host associations, and role as a disease vector are not well known. We collected I. apronophorus from several locations in Romania. Morphological identification of ticks was confirmed by analysis of 16S rDNA and 12S rDNA gene sequences. We report new host associations of I. apronophorus, which was collected from dogs, foxes, and a hare-all new hosts for this tick species in Romania. Furthermore, we report for the first time occurrence of Ehrlichia sp. HF in I. apronophorus. Ehrlichia sp. HF was identified by sequencing a part of the 16S rDNA gene and was found in 16% (3/19) of the tested ticks. Ehrlichia sp. HF has not been previously reported in Eastern Europe and seems to have a much larger geographic distribution than previously known. Currently, it is unknown whether I. apronophorus is a competent vector for Ehrlichia sp. HF, or if the findings in this study represent infection in the hosts, namely dogs and fox.

  • 42.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tamba, Paula
    Inst Diag & Anim Hlth, Romania.
    Stefanache, Mircea
    PAUMI VET Private Vet Clin, Romania.
    Radbea, Gabriel
    Sal Vet Private Vet Clin, Romania.
    Frangoulidis, Dimitrios
    Bundeswehr Inst Microbiol, Germany.
    Tomaso, Herbert
    Friedrich Loeffler Inst, Germany.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Dobler, Gerhard
    Bundeswehr Inst Microbiol, Germany;German Ctr Infect Res DZIF Partner Munich, Germany.
    Chitimia-Dobler, Lidia
    Inst Diag & Anim Hlth, Romania;Bundeswehr Inst Microbiol, Germany;German Ctr Infect Res DZIF Partner Munich, Germany.
    Molecular survey of neglected bacterial pathogens reveals an abundant diversity of species and genotypes in ticks collected from animal hosts across Romania2018In: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 11, article id 144Article in journal (Refereed)
    Abstract [en]

    Background: Ticks are transmitting a wide range of bacterial pathogens that cause substantial morbidity and mortality in domestic animals. The full pathogen burden transmitted by tick vectors is incompletely studied in many geographical areas, and extensive studies are required to fully understand the diversity and distribution of pathogens transmitted by ticks. Results: We sampled 824 ticks of 11 species collected in 19 counties in Romania. Ticks were collected mainly from dogs, but also from other domestic and wild animals, and were subjected to molecular screening for pathogens. Rickettsia spp. was the most commonly detected pathogen, occurring in 10.6% (87/824) of ticks. Several species were detected: Rickettsia helvetica, R. raoultii, R. massiliae, R. monacensis, R. slovaca and R. aeschlimannii. A single occurrence of the zoonotic bacterium Bartonella vinsonii berkhoffii was detected in a tick collected from a dog. Anaplasma phagocytophilum occurred in four samples, and sequences similar to Anaplasma marginale/ovis were abundant in ticks from ruminants. In addition, molecular screening showed that ticks from dogs were carrying an Ehrlichia species identical to the HF strain as well as the enigmatic zoonotic pathogen "Candidatus Neoehrlichia mikurensis". An organism similar to E. chaffeensis or E. muris was detected in an Ixodes ricinus collected from a fox. Conclusions: We describe an abundant diversity of bacterial tick-borne pathogens in ticks collected from animal hosts in Romania, both on the level of species and genotypes/strains within these species. Several findings were novel for Romania, including Bartonella vinsonii subsp. berkhoffii that causes bacteremia and endocarditis in dogs. "Candidatus Neoehrlichia mikurensis" was detected in a tick collected from a dog. Previously, a single case of infection in a dog was diagnosed in Germany. The results warrant further studies on the consequences of tick-borne pathogens in domestic animals in Romania.

  • 43.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tamba, Paula
    Inst Diag & Anim Hlth, Romania.
    Stefanache, Mircea
    PAUMI VET Private Vet Clin, Romania.
    Radbea, Gabriel
    Sal Vet Private Vet Clin, Romania.
    Rubel, Franz
    Univ Vet Med Vienna, Austria.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Dobler, Gerhard
    German Ctr Infect Res DZIF Partner Munich, Germany.
    Chitimia-Dobler, Lidia
    Inst Diag & Anim Hlth, Romania ; German Ctr Infect Res DZIF Partner Munich, Germany.
    Babesia, Theileria, and Hepatozoon species in ticks infesting animal hosts in Romania2017In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 116, no 8, p. 2291-2297Article in journal (Refereed)
    Abstract [en]

    Babesia spp., Theileria spp., and Hepatozoon spp. are tick-transmitted apicomplexan parasites that cause several important diseases in animals. To increase current knowledge about the diversity of tick-transmitted pathogens in Romania, we investigated the occurrence of Babesia spp., Theileria spp., and Hepatozoon spp. in a wide range of tick species infesting animal hosts. We collected 852 ticks from 10 different animal species from 20 counties in Romania. The assessment was based on detection of parasite DNA by PCR. Five different apicomplexan parasite species were detected; among them three different species of Babesia: B. canis, B. microti, and B. ovis. Hepatozoon canis was the most frequently detected parasite, found predominately in Ixodes ricinus ticks collected from domestic dogs. It was also detected in I. ricinus collected from goat, fox, and cat. Furthermore, H. canis was found in Haemaphysalis punctata and Haemaphysalis concinna ticks. In addition, Theileria buffeli was detected in Rhipicephalus bursa ticks collected from cattle.

  • 44.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tamba, Paula
    Institute for Diagnosis and Animal Health, Romania.
    Stefanache, Mircea
    PAUMI-VET Private Veterinary Clinics, Romania.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Dobler, Gerhard
    German Center for Infection Research, Germany.
    Chitimia-Dobler, Lidia
    German Center for Infection Research, Germany.
    Canine tick-borne diseases in pet dogs from Romania2017In: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 10, article id 2092Article in journal (Refereed)
    Abstract [en]

    Background: Tick-borne diseases are of substantial concern worldwide for animals as well as humans. Dogs have been a human companion for millennia, and their significant impact on human life renders disease in dogs to be of great concern. Tick-borne diseases in dogs represent a substantial diagnostic challenge for veterinarians in that clinical signs are often diffuse and overlapping. In addition, co-infections with two or more pathogens enhance this problem further. Molecular methods are useful to disentangle co-infections and to accurately describe prevalence and geographical distribution of tick-borne diseases. At this point, this information is lacking in many areas worldwide. Romania is one such area, where prevalence and distribution of several important pathogens need to be further investigated. To address this, we screened blood samples from 96 sick dogs with molecular methods for eight different pathogens including Babesia spp., Theileria spp., Hepatozoon spp., Anaplasma spp., Ehrlichia spp., "Candidatus Neoehrlichia mikurensis", Mycoplasma spp., and Borrelia spp. Results: As many as 45% (43/ 96) of the dogs in the study were infected with protozoan parasites. Babesia canis was the most frequent of these (28 infected dogs), whereas Hepatozoon canis was detected in 15% (14/ 96) and Babesia gibsoni was found in a single sample. Bacterial infection with Mycoplasma spp. occurred in 18% (17/ 96) of the sampled dogs. Obtained bacterial sequences revealed the occurrence of two species: Mycoplasma canis and "Candidatus Mycoplasma haematoparvum". In several cases co-infection with protozoan parasites and Mycoplasma sp. were detected. All dogs were negative for Anaplasma spp., Ehrlichia spp., "Ca. Neoehrlichia mikurensis", and for Borrelia spp. Conclusions: The results from the present study reinforce the notion that Babesia canis is an important pathogen in the Romanian dog population. However, more surprisingly, another protozoan species, H. canis, seems to be infecting dogs to a larger extent than previously recognized in Romania. Well-known tick-borne bacterial disease agents such as Anaplasma spp. and Borrelia spp. were not detected. In contrast, less wellstudied bacteria such as hemotropic Mycoplasma spp. were detected frequently. Moreover, co-infection might aggravate disease and complicate diagnosis and should be further studied in dogs.

  • 45.
    Andersson, Martin O.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Vichova, Bronislava
    Slovak Acad Sci, Slovakia.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Krzyzanowska, Sandra
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Karlsson, Maria E.
    Swedish University of Agricultural Sciences.
    Co-infection with Babesia divergens and Anaplasma phagocytophilum in cattle (Bos taurus), Sweden2017In: Ticks and Tick-borne Diseases, ISSN 1877-959X, E-ISSN 1877-9603, Vol. 8, no 6, p. 933-935Article in journal (Refereed)
    Abstract [en]

    Babesiosis is a severe disease in cattle worldwide. In Europe, the main causative agent of bovine babesiosis is Babesia divergens. In some areas, this species is reported to have declined or even disappeared, and its etiological role overtaken by other piroplasmid species. Moreover, co-infection with other tick-transmitted pathogens can be expected to complicate diagnosis in cattle. Hence, molecular identification of the causative agent of babesiosis should be a priority. Therefore, samples from 71 domestic cattle, 39 with clinical signs of babesiosis and 32 without, from southern Sweden were screened for Babesia spp. and Anaplasma spp. using molecular methods Babesia divergens was detected in 38 of the samples, and Anaplasma phagocytophilum in 17. Co-infections with both pathogens were frequent, occurring in 18% of the animals with a B. divergens infection. The possibility of co-infection should be considered in diagnosis and treatment of bovine babesiosis.

  • 46. Andersson, Mats
    Miljöfrågor engagerar många2016In: BarometernArticle in journal (Other (popular science, discussion, etc.))
  • 47.
    Andersson, Michael R.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Functional aspects of inorganic phosphate transport2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Inorganic phosphate is an essential nutrient for all organisms. It is required for many cellular components as nucleic acids and phospholipids, and as energy-carrying compounds such as ATP. Thus, a regulated uptake of this pivotal nutrient is of outermost importance. Depending of the availability of phosphate in the surroundings the yeast Saccharomyces cerevisiae make use of two different systems for transporting phosphate into the interior of the cell: a low-affinity system that is active during surplus phosphate conditions and a high-affinity system that is active when the availability becomes limited. This thesis focuses on the high-affinity system, which is comprised of the Pho84 and Pho89 transporters. Of the two transporters, Pho84 is the predominant one, responsible for almost all phosphate uptake during low phosphate conditions, and the contribution of Pho89 is of minor importance. Hence Pho84 is by far the most well characterized phosphate transporter. Even though much is known about phosphate transporters in yeast little in known about how phosphate is transported. The work in this thesis aims to broaden the knowledge about the transport mechanism by the means of site-directed mutagenesis and functional characterization. Also the similarity of Pho84 to glucose sensors and the potential role of conserved residues in phosphate signaling are investigated. By the use of a high-affinity system deletion strain (∆Pho84 ∆Pho89), we also managed to investigate the functional importance of well conserved residues in Pho89. In summary: the work presented in this thesis has contributed to increase the knowledge about transport mechanisms in phosphate transporters.

  • 48.
    Andersson, Michael R.
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Samyn, Dieter R.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Persson, Bengt L.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Mutational analysis of conserved glutamic acids of Pho89, a Saccharomyces cerevisiae high-affinity inorganic phosphate:Na+ symporter2012In: Biologia (Bratislava), ISSN 0006-3088, E-ISSN 1336-9563, Vol. 67, no 6, p. 1056-1061Article in journal (Refereed)
    Abstract [en]

    In Saccharomyces cerevisiae, the high-affinity phosphate transport system comprises the Pho84 and Pho89 permeases. The Pho89 permease catalyzes import of inorganic phosphate in a symport manner by utilizing Na+ ions as co-solute. We have addressed the functional importance of two glutamic acid residues at positions 55 and 491. Both residues are highly conserved amongst members of the inorganic phosphate transporter (PiT) family, which might be an indication of functional importance. Moreover, both residues have been shown to be of critical importance in the hPit2 transporter. We have created site-directed mutations of both E55 and E491 to lysine and glutamine. We observed that in all four cases there is a dramatic impact on the transport activity, and thus it seems that they indeed are of functional importance. Following these observations, we addressed the membrane topology of this protein by using several prediction programs. TOPCONS predicts a 7-5 transmembrane segment organization, which is the most concise topology as compared to the hPiT2 transporter. By understanding the functionality of these residues, we are able to correlate the Pho89 topology to that of the hPiT2, and can now further analyze residues which might play a role in the transport activity.

  • 49. Andersson, P
    et al.
    Edman, Kjell
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Lindberg, A. Michael
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Molecular analysis of the echovirus 18 prototype2002In: Virus research, Vol. 85, p. 71-83Article in journal (Refereed)
  • 50.
    Andersson, Solbritt
    et al.
    Ekologiska institutionen, Lunds Universitet.
    Ek, Hans
    Ekologiska institutionen, Lunds Universitet.
    Söderström, Bengt
    Ekologiska institutionen, Lunds Universitet.
    Effects of liming on the uptake of organic and inorganic nitrogen by mycorrhizal (Paxillus involutus) and non-mycorrhizal Pinus sylvestris plants1997In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 135, no 4, p. 763-771Article in journal (Refereed)
    Abstract [en]

    Seedlings of Pinus sylvestris L. were grown in Plexiglas(R) observation chambers in limed (CaCO3, pH 5.0 and 5.9) and untreated (pH 4.1) peat. The seedlings were either colonized by the mycorrhizal fungus Paxillus involutus (Batsch: Fr.) Fr. Or were non-mycorrhizal. After 18 wk in the observation chambers, N-15-labelled organic nitrogen, as lyophilized and ground mycelium of Suillus variegatus (Swartz: Fr.) O. Kuntze, or ammonium, was added to the peat. The plants were harvested after an uptake period of 14 d. Irrespective of the nitrogen form added, liming decreased both the content and concentration of N-15 in nonmycorrhizal plants, and, to a lesser extent, those in mycorrhizal plants. In mycorrhizal plants the uptake of N-15 was not correlated with area colonized by the mycorrhizal mycelium. The amount of KCl-extractable N-15 in peat without plants and mycorrhizal fungi decreased with liming. It is proposed that liming induced chemical or microbial immobilization of the added N-15. This is suggested to be the main reason for the decreased uptake of N-15 in lime treatments.

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