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1.	Andersson, Mats X., 1977, et al. (författare) Involvement of the Electrophilic Isothiocyanate Sulforaphane in Arabidopsis Local Defense Responses 2015 Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 167:1 Tidskriftsartikel (refereegranskat)abstract Plants defend themselves against microbial pathogens through a range of highly sophisticated and integrated molecular systems. Recognition of pathogen-secreted effector proteins often triggers the hypersensitive response (HR), a complex multicellular defense reaction where programmed cell death of cells surrounding the primary site of infection is a prominent feature. Even though the HR was described almost a century ago, cell-to-cell factors acting at the local level generating the full defense reaction have remained obscure. In this study, we sought to identify diffusible molecules produced during the HR that could induce cell death in naive tissue. We found that 4-methylsulfinylbutyl isothiocyanate (sulforaphane) is released by Arabidopsis (Arabidopsis thaliana) leaf tissue undergoing the HR and that this compound induces cell death as well as primes defense in naive tissue. Two different mutants impaired in the pathogen-induced accumulation of sulforaphane displayed attenuated programmed cell death upon bacterial and oomycete effector recognition as well as decreased resistance to several isolates of the plant pathogen Hyaloperonospora arabidopsidis. Treatment with sulforaphane provided protection against a virulent H. arabidopsidis isolate. Glucosinolate breakdown products are recognized as antifeeding compounds toward insects and recently also as intracellular signaling and bacteriostatic molecules in Arabidopsis. The data presented here indicate that these compounds also trigger local defense responses in Arabidopsis tissue.
2.	Nilsson, Anders K., 1982, et al. (författare) Acylated monogalactosyl diacylglycerol : prevalence in the plant kingdom and identification of an enzyme catalyzing galactolipid head group acylation in Arabidopsis thaliana 2015 Ingår i: The Plant Journal. - : Wiley-Blackwell. - 0960-7412 .- 1365-313X. ; 84:6, s. 1152-1166 Tidskriftsartikel (refereegranskat)abstract The lipid phase of the thylakoid membrane is mainly composed of the galactolipids mono-and digalactosyl diacylglycerol (MGDG and DGDG, respectively). It has been known since the late 1960s that MGDG can be acylated with a third fatty acid to the galactose head group (acyl-MGDG) in plant leaf homogenates. In certain brassicaceous plants like Arabidopsis thaliana, the acyl-MGDG frequently incorporates oxidized fatty acids in the form of the jasmonic acid precursor 12-oxo-phytodienoic acid (OPDA). In the present study we further investigated the distribution of acylated and OPDA-containing galactolipids in the plant kingdom. While acyl-MGDG was found to be ubiquitous in green tissue of plants ranging from non-vascular plants to angiosperms, OPDA-containing galactolipids were only present in plants from a few genera. A candidate protein responsible for the acyl transfer was identified in Avena sativa (oat) leaf tissue using biochemical fractionation and proteomics. Knockout of the orthologous gene in A. thaliana resulted in an almost total elimination of the ability to form both non-oxidized and OPDA-containing acyl-MGDG. In addition, heterologous expression of the A. thaliana gene in E. coli demonstrated that the protein catalyzed acylation of MGDG. We thus demonstrate that a phylogenetically conserved enzyme is responsible for the accumulation of acyl-MGDG in A. thaliana. The activity of this enzyme in vivo is strongly enhanced by freezing damage and the hypersensitive response.
3.	Johansson, Oskar N., 1984, et al. (författare) A quick and robust method for quantification of the hypersensitive response in plants 2015 Ingår i: Peerj. - : PeerJ. - 2167-8359. ; 3 Tidskriftsartikel (refereegranskat)abstract One of the most studied defense reactions of plants against microbial pathogens is the hypersensitive response (HR). The HR is a complex multicellular process that involves programmed cell death at the site of infection. A standard method to quantify plant defense and the HR is to measure the release of cellular electrolytes into water after infiltration with pathogenic bacteria. In this type of experiment, the bacteria are typically delivered into the plant tissue through syringe infiltration. Here we report the development of a vacuum infiltration protocol that allows multiple plant lines to be infiltrated simultaneously and assayed for defense responses. Vacuum infiltration did not induce more wounding response in Arabidopsis leaf tissue than syringe inoculation, whereas throughput and reproducibility were improved. The method was used to study HR-induced electrolyte loss after treatment with the bacterium Pseudomonas syringae pv. tomato DC3000 harboring the effector AvrRpm1, AvrRpt2 or AvrRps4. Specifically, the influence of bacterial titer on AvrRpm1-induced HR was investigated. Not only the amplitude, but also the timing of the maximum rate of the HR reaction was found to be dose-dependent. Finally, using vacuum infiltration, we were able quantify induction of phospholipase D activity after AvrRpm1 recognition in leaves labeled with (PO4)-P-33.
4.	Johansson, Oskar N., 1984, et al. (författare) Phenomics reveals a novel putative chloroplast fatty acid transporter in the marine diatom Skeletonema marinoi involved in temperature acclimation 2019 Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9 Tidskriftsartikel (refereegranskat)abstract Diatoms are the dominant phytoplankton in temperate oceans and coastal regions and yet little is known about the genetic basis underpinning their global success. Here, we address this challenge by developing the first phenomic approach for a diatom, screening a collection of randomly mutagenized but identifiably tagged transformants. Based upon their tolerance to temperature extremes, several compromised mutants were identified revealing genes either stress related or encoding hypothetical proteins of unknown function. We reveal one of these hypothetical proteins is a novel putative chloroplast fatty acid transporter whose loss affects several fatty acids including the two omega-3, long-chain polyunsaturated fatty acids - eicosapentaenoic and docosahexaenoic acid, both of which have medical importance as dietary supplements and industrial significance in aquaculture and biofuels. This mutant phenotype not only provides new insights into the fatty acid biosynthetic pathways in diatoms but also highlights the future value of phenomics for revealing specific gene functions in these ecologically important phytoplankton.
5.	Najm, Svetlana, et al. (författare) Effects of a lipid emulsion containing fish oil on polyunsaturated fatty acid profiles, growth and morbidities in extremely premature infants: A randomized controlled trial 2017 Ingår i: Clinical Nutrition ESPEN. - : Elsevier BV. - 2405-4577. ; 20, s. 17-23 Tidskriftsartikel (refereegranskat)abstract © 2017 The Authors Background & aims The purpose of the study was to compare the effects of the parenteral emulsion SMOFlipid ® , with 15% fish oil, with Clinoleic ® on retinopathy of prematurity (ROP) and other morbidities and growth, and to compare their impact on longitudinal serum levels of fatty acids. Retinopathy of prematurity, other morbidity and growth were correlated with each parenteral lipid supplement. Methods Ninety infants born at gestational age < 28 weeks were randomized to treatment with SMOFlipid ® or Clinoleic ® . Two thirds (66%) of the infants received parenteral nutrition for up to 14 days birth (median 8, range 2–14 days), and additional 25% of the infants received for up to 28 days after birth (median 21, range 15–28 days). Cord blood samples and then venous blood samples were obtained at ages 1, 7, 14, and 28 days and at postmenstrual age (PMA) 32, 36, and 40 weeks. Breastmilk was collected at postnatal day 7, and at PMA 32 and 40 weeks. Serum phospholipid and breastmilk total fatty acids were analyzed by gas chromatography–mass spectrometry. Treatment groups were compared with regard to ROP, bronchopulmonary dysplasia, necrotizing enterocolitis, patent ductus arteriosus sepsis and growth between birth and 36 weeks. Results Infants on SMOFlipid ® had higher fractions of omega-3 LCPUFA eicosapentaenoic acid (EPA) and slightly higher omega-3 LCPUFA docosahexaenoic acid (DHA) fraction and a decreased arachidonic acid (AA) to DHA ratio from one week after birth up to 32 postmenstrual weeks compared to infants on Clinoleic ® . Treatment groups did not differ in morbidities or growth. Conclusion Supplementation with SMOFlipid ® containing 15% fish oil during parenteral nutrition increased EPA substantially, DHA marginally, reduced AA and decreased AA to DHA ratio. It did not reduce morbidity or affect growth. Since extremely preterm infants accumulate a large deficit of DHA and AA, studies on more prolonged or different levels of DHA and AA supplementation are warranted.
6.	Nilsson, Anders K., 1982, et al. (författare) The activity of HYDROPEROXIDE LYASE 1 regulates accumulation of galactolipids containing 12-oxo-phytodienoic acid in Arabidopsis 2016 Ingår i: Journal of Experimental Botany. - : Oxford University Press (OUP). - 0022-0957 .- 1460-2431. ; 67:17, s. 5133-5144 Tidskriftsartikel (refereegranskat)abstract Arabidopsis produces galactolipids containing esters of 12-oxo-phytodienoic acid (OPDA) and dinor-12-oxo-phytodienoic acid (dnOPDA). These lipids are referred to as arabidopsides and accumulate in response to abiotic and biotic stress. We explored the natural genetic variation found in 14 different Arabidopsis accessions to identify genes involved in the formation of arabidopsides. The accession C24 was identified as a poor accumulator of arabidopsides whereas the commonly used accession Col-0 was found to accumulate comparably large amounts of arabidopsides in response to tissue damage. A quantitative trait loci analysis of an F-2 population created from a cross between C24 and Col-0 located a region on chromosome four strongly linked to the capacity to form arabidopsides. Expression analysis of HYDROPEROXIDE LYASE 1 (HPL1) showed large differences in transcript abundance between accessions. Transformation of Col-0 plants with the C24 HPL1 allele under transcriptional regulation of the 35S promoter revealed a strong negative correlation between HPL1 expression and arabidopside accumulation after tissue damage, thereby strengthening the view that HPL1 competes with ALLENE OXIDE SYNTHASE (AOS) for lipid-bound hydroperoxide fatty acids. We further show that the last step in the synthesis of galactolipid-bound OPDA and dnOPDA from unstable allene oxides is exclusively enzyme-catalyzed and not the result of spontaneous cyclization. Thus, the results presented here together with previous studies suggest that all steps in arabidopside biosynthesis are enzyme-dependent and apparently all reactions can take place with substrates being esterified to galactolipids.
7.	Adolfsson, Lisa, 1984, et al. (författare) Mycorrhiza Symbiosis Increases the Surface for Sunlight Capture in Medicago truncatula for Better Photosynthetic Production 2015 Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:1 Tidskriftsartikel (refereegranskat)abstract Arbuscular mycorrhizal (AM) fungi play a prominent role in plant nutrition by supplying mineral nutrients, particularly inorganic phosphate (Pi), and also constitute an important carbon sink. AM stimulates plant growth and development, but the underlying mechanisms are not well understood. In this study, Medicago truncatula plants were grown with Rhizophagus irregularis BEG141 inoculum (AM), mock inoculum (control) or with Pi fertilization. We hypothesized that AM stimulates plant growth through either modifications of leaf anatomy or photosynthetic activity per leaf area. We investigated whether these effects are shared with Pi fertilization, and also assessed the relationship between levels of AM colonization and these effects. We found that increased Pi supply by either mycorrhization or fertilization led to improved shoot growth associated with increased nitrogen uptake and carbon assimilation. Both mycorrhized and Pi-fertilized plants had more and longer branches with larger and thicker leaves than the control plants, resulting in an increased photosynthetically active area. AM-specific effects were earlier appearance of the first growth axes and increased number of chloroplasts per cell section, since they were not induced by Pi fertilization. Photosynthetic activity per leaf area remained the same regardless of type of treatment. In conclusion, the increase in growth of mycorrhized and Pi-fertilized Medicago truncatula plants is linked to an increase in the surface for sunlight capture, hence increasing their photosynthetic production, rather than to an increase in the photosynthetic activity per leaf area.
8.	Amato, Alberto, et al. (författare) Grazer-induced transcriptomic and metabolomic response of the chain-forming diatom Skeletonema marinoi 2018 Ingår i: ISME Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 12, s. 1594-1604 Tidskriftsartikel (refereegranskat)abstract Diatoms and copepods are main actors in marine food webs. The prey-predator interactions between them affect bloom dynamics, shape marine ecosystems and impact the energy transfer to higher trophic levels. Recently it has been demonstrated that the presence of grazers may affect the diatom prey beyond the direct effect of grazing. Here, we investigated the response of the chain-forming centric diatom Skeletonema marinoi to grazer cues, including changes in morphology, gene expression and metabolic profile. S. marinoi cells were incubated with Calanus finmarchicus or with Centropages typicus and in both cases responded by reducing the chain length, whereas changes in gene expression indicated an activation of stress response, changes in the lipid and nitrogen metabolism, in cell cycle regulation and in frustule formation. Transcripts linked to G protein-coupled receptors and to nitric oxide synthesis were differentially expressed suggesting involvement of these signalling transduction pathways in the response. Downregulation of a lipoxygenase in the transcriptomic data and of its products in the metabolomic data also indicate an involvement of oxylipins. Our data contribute to a better understanding of the gene function in diatoms, providing information on the nature of genes implicated in the interaction with grazers, a crucial process in marine ecosystems.
9.	Ankarberg-Lindgren, Carina, 1963, et al. (författare) High-sensitivity quantification of serum androstenedione, testosterone, dihydrotestosterone, estrone and estradiol by gas chromatography-tandem mass spectrometry with sex- and puberty-specific reference intervals. 2018 Ingår i: The Journal of steroid biochemistry and molecular biology. - : Elsevier BV. - 1879-1220 .- 0960-0760. ; 183, s. 116-124 Tidskriftsartikel (refereegranskat)abstract Androgen and estrogen determinations serve as important diagnostic markers in a variety of clinical conditions. However, one challenge is to enhance assay sensitivity for determination in the lowest range, such as in prepubertal children. We here present a recently developed gas chromatography-tandem mass spectrometry (GC-MS/MS) method for determination of androstenedione (A4), dihydrotestosterone (DHT), testosterone (T), estrone (E1), and estradiol (E2) in children, which we have compared with the sensitive radioimmunoassays; E2 extraction-RIA and T-RIA.Steroids were extracted in ethyl acetate n-hexane solution from serum spiked with isotopically labeled internal standard and derivatized sequentially with pentafluorobenzyl bromide, pentafluorobenzyl hydroxylamine and pentafluoropropionic acid anhydride and analyzed by GC-MS/MS using a triple quadrupole mass spectrometer operated in negative chemical ionization mode. Leftover routine samples (n=414) were used to evaluate the concordance between GC-MS/MS and RIAs and the validity of GC-MS/MS for pediatrics; of these samples, 101 were from seemingly healthy children. Pubertal stage was recorded for reference interval evaluation.Lower limit of detection for A4, T, DHT, E1, and E2 were 0.1nmol/L, 0.1nmol/L, 27pmol/L, 9pmol/L, and 2pmol/L, respectively. Good agreement was found between GC-MS/MS and T-RIA (r=0.98) as well as between GC-MS/MS and E2 extraction-RIA (r=0.98, for E2 concentrations above 14pmol/L). In boys, T and DHT increased significantly from prepuberty throughout pubertal development, and in girls the same increase was observed for E1 and E2. The greatest increase in A4 for both genders, as well as E1 and E2 in boys and T and DHT in girls, occurred in mid to late puberty.We report the development of a GC-MS/MS method sensitive enough to accurately determine serum levels of androgens and estrogens in children.
10.	Arrhenius, Åsa, 1973, et al. (författare) Effects of antimycotics and fungicides to limnic microbial biofilms – a case study of the run-off from a golf course 2016 Ingår i: 4th Biofilm Workshop - Basis and application of biofilms to assess the effects of environmental change in aquatic ecosystems - Girona, 7-8 April 2016. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Antimycotic pharmaceuticals and fungicides are widely used for treating fungal infections in humans and animals and control pests in different areas and applications. They enter the aquatic environment either after passage through the body, or after being rinsed off from areas of application (skin, crops, farmland etc.). However, substantial knowledge gaps currently hamper a proper environmental risk assessment of the individual antimycotics and fungicides and their mixtures for marine and freshwater environments. Previously it has been shown that clotrimazole, a marine priority pollutant, affected sterol composition of marine microalgal communities already at 50 pmol/L which indicates effects at environmental concentrations. In this presentation we will discuss results from our work with limnic microbial biofilms and effects from antimycotics and fungicides individually and as mixtures. Endpoints include growth, pigment pattern, sterol composition, and species composition. Special focus will be on a case study from a Swedish golf course with a high usage of fungicides. Based on an analytical survey we prepared a worst-case-mixture study were we exposed biofilms in indoor microcosms for several days. Effects on growth and some shifts in microalgal species composition could be observed at concentrations relevant for the nearby golf area. Analysis of sterol composition and analytical confirmation of exposure concentrations are work in progress. The work is performed within the Swedish Formas-funded project “Aquatic Environmental Risk Assessment of Antimycotics”.
11.	Arrhenius, Åsa, 1973, et al. (författare) Toxicity of the fungicide ketoconazole to freshwater microalgal communities 2015 Ingår i: SETAC Europe 25th Annual Meeting, Barcelona Spain. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Antimycotic pharmaceuticals are widely used for treating fungal infections in humans and animals. They enter the aquatic environment either after passage through the body, or after being rinsed off if they are topically applied. However, substantial knowledge gaps currently hamper a proper environmental risk assessment of the individual antimycotics and their mixtures for marine and freshwater environments. Clotrimazole, a marine priority pollutant, affected sterol composition of marine microalgal communities already at 50 pmol/L which indicates effects already at environmental concentrations. In the present study we focus on ketoconazole (also an azole fungicide) and toxicity to freshwater microalgal communities. A concentration response curve was first established using pigment profiles (HPLC) as endpoint which resulted in an EC50 of around 1 micromol/L. During autumn 2014 we repeated the study but focused on the lower concentration range from 0.0001 to 1 micromol/L. Results on chlorophyll a show similar patterns as in the initial study. The experiments were finished during autumn 2014 and are currently under final evaluation and sterol analysis, species determinations and analytical confirmation of exposure concentrations are currently evaluated. The work is performed within the Swedish Formas-funded project “Aquatic Environmental Risk Assessment of Antimycotics”.
12.	D'Ambrosio, J. M., et al. (författare) Phospholipase C2 Affects MAMP-Triggered Immunity by Modulating ROS Production 2017 Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 175:2, s. 970-981 Tidskriftsartikel (refereegranskat)abstract The activation of phosphoinositide-specific phospholipase C (PI-PLC) is one of the earliest responses triggered by the recognition of several microbe-associated molecular patterns (MAMPs) in plants. The Arabidopsis (Arabidopsis thaliana) PI-PLC gene family is composed of nine members. Previous studies suggested a role for PLC2 in MAMP-triggered immunity, as it is rapidly phosphorylated in vivo upon treatment with the bacterial MAMP flg22. Here, we analyzed the role of PLC2 in plant immunity using an artificial microRNA to silence PLC2 expression in Arabidopsis. We found that PLC2-silenced plants are more susceptible to the type III secretion system-deficient bacterial strain Pseudomonas syringae pv tomato (Pst) DC3000 hrcC2 and to the nonadapted pea (Pisum sativum) powdery mildew Erysiphe pisi. However, PLC2-silenced plants display normal susceptibility to virulent (Pst DC3000) and avirulent (Pst DC3000 AvrRPM1) P. syringae strains, conserving typical hypersensitive response features. In response to flg22, PLC2-silenced plants maintain wild-type mitogen-activated protein kinase activation and PHI1, WRKY33, and FRK1 immune marker gene expression but have reduced reactive oxygen species (ROS)-dependent responses such as callose deposition and stomatal closure. Accordingly, the generation of ROS upon flg22 treatment is compromised in the PLC2-defficient plants, suggesting an effect of PLC2 in a branch of MAMP-triggered immunity and nonhost resistance that involves early ROS-regulated processes. Consistently, PLC2 associates with the NADPH oxidase RBOHD, suggesting its potential regulation by PLC2.
13.	Eriksson, Martin, 1970, et al. (författare) Long-term effects of the antibacterial agent triclosan on marine periphyton communities 2015 Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 34:9, s. 2067-2077 Tidskriftsartikel (refereegranskat)abstract Triclosan is a widely used antibacterial agent that has become a ubiquitous contaminant in freshwater, estuary, and marine environments. Concerns about potential adverse effects of triclosan have been described in several recent risk assessments. Its effects on freshwater microbial communities have been well studied, but studies addressing effects on marine microbial communities are scarce. In the present study, the authors describe short- and long-term effects of triclosan on marine periphyton (microbial biofilm) communities. Short-term effects on photosynthesis were estimated after 60min to 210min of exposure. Long-term effects on photosynthesis, chlorophyll a fluorescence, pigment content, community tolerance, and bacterial carbon utilization were studied after exposing periphyton for 17d in flow-through microcosms to 0.316nM to 10000nM triclosan. Results from the short-term studies show that triclosan is toxic to periphyton photosynthesis. Half maximal effective concentration (EC50) values of 1080nM and 3000nM were estimated using (CO2)-C-14-incorporation and pulse amplitude modulation (PAM) fluorescence measurements, respectively. After long-term triclosan exposure in flow-through microcosms, photosynthesis estimated using PAM fluorometry was not inhibited by triclosan concentrations up to 1000nM but instead increased with increasing triclosan concentration. Similarly, at exposure concentrations of 31.6nM and higher, triclosan caused an increase in photosynthetic pigments. At 316nM triclosan, the pigment amounts were increased by a factor of 1.4 to 1.9 compared with the control level. Pollution-induced community tolerance was observed for algae and cyanobacteria at 100nM triclosan and higher. Despite the widespread use of triclosan as an antibacterial agent, the compound did not have any effects on bacterial carbon utilization after long-term exposure.
14.	Fahlberg, Per, et al. (författare) Involvement of lipid transfer proteins in resistance against a non-host powdery mildew in Arabidopsis thaliana 2019 Ingår i: Molecular Plant Pathology. - : Wiley. - 1464-6722 .- 1364-3703. ; 20:1, s. 69-77 Tidskriftsartikel (refereegranskat)abstract Non-specific lipid transfer proteins (LTPs) are involved in the transport of lipophilic compounds to the cuticular surface in epidermal cells and in the defence against pathogens. The role of glycophosphatidylinositol (GPI)-anchored LTPs (LTPGs) in resistance against non-host mildews in Arabidopsis thaliana was investigated using reverse genetics. Loss of either LTPG1, LTPG2, LTPG5 or LTPG6 increased the susceptibility to penetration of the epidermal cell wall by Blumeria graminis f. sp. hordei (Bgh). However, no impact on pre-penetration defence against another non-host mildew, Erysiphe pisi (Ep), was observed. LTPG1 was localized to papillae at the sites of Bgh penetration. This study shows that, in addition to the previously known functions, LTPGs contribute to pre-invasive defence against certain non-host powdery mildew pathogens.
15.	Genva, M., et al. (författare) New insights into the biosynthesis of esterified oxylipins and their involvement in plant defense and developmental mechanisms 2019 Ingår i: Phytochemistry Reviews. - : Springer Science and Business Media LLC. - 1568-7767 .- 1572-980X. ; 18:1, s. 343-358 Tidskriftsartikel (refereegranskat)abstract Plant oxylipins produced following oxidation of unsaturated fatty acids are structurally diverse metabolites that play crucial developmental and defensive roles. Whereas free oxylipins are well studied, oxylipins esterified in complex lipids such as galacto- and phospholipids are thought to be rare and have unclear roles. In the last few years, new analytical methods have been developed, leading to the discovery of many esterified oxylipins in a variety of plant species. This suggests that these molecules may be ubiquitous plant metabolites. While their precise functions are unclear, esterified oxylipins seem to play important roles in plant development and defense. This review focuses on new insights regarding diversity, biosynthesis and function of those interesting and understudied molecules.
16.	Grebner, Wiebke, 1985, et al. (författare) Induction of defensive traits in marine plankton—new copepodamide structures 2019 Ingår i: Limnology and Oceanography. - : Wiley. - 0024-3590 .- 1939-5590. ; 64:2, s. 820-831 Tidskriftsartikel (refereegranskat)abstract Marine zooplankton release chemical cues, which trigger defenses in unicellular phytoplankton, such as increased toxin production and changes of colony sizes. Here, we identify the structure of two novel alarm cues belonging to the group of copepodamides. Similar to the known copepodamides, one of the compounds described is shown to trigger both amnesic and paralytic shellfish toxin production and chain length shortening in Skeletonema marinoi. In addition, we report the putative structures of another 21 copepodamides, which constitute 28% of the total copepodamides extractable from whole animals, suggesting that the copepodamide concentrations have been underestimated in earlier studies. We introduce a structure‐based nomenclature to handle the increasing number of copepodamides. Analysis of 12 copepod species showed that marine calanoid and freshwater cyclopoid copepods contain copepodamides. The only harpacticoid included in the analysis, Tigriopus californicus, did not appear to produce detectable amounts of copepodamides. Feeding experiments revealed that copepodamide compositions depend on both diet and species‐specific properties. Copepodamides induce both morphological and biochemical defensive traits in phytoplankton and may drive large‐scale trait–mediated effects in marine food webs. The more comprehensive list of copepodamides reported here makes it possible to explore the role of the copepodamide signaling system in the pelagic ecosystem in greater detail.
17.	Inganäs, O, et al. (författare) Alternating fluorene copolymer–fullerene blend solar cells 2017 Ingår i: Organic Photovoltaics: Mechanisms, Materials, and Devices. - : CRC Press. - 9781420026351 ; , s. 387-402 Bokkapitel (övrigt vetenskapligt/konstnärligt)
18.	Johansson, Karin S L, et al. (författare) Molecular basis of variation in stomatal responsiveness to elevated CO2 2015 Ingår i: Agriculture and Climate Change - Adapting Crops to Increased Uncertainty. 15-17 February 2015, Amsterdam, the Netherlands. Procedia Environmental Sciences. - : Elsevier. - 1878-0296. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Stomata are small pores in the surface of plant leaves, balancing the uptake of CO2 against the loss of water vapour. As drought stress is projected to increase in many parts of the world, an improved understanding of how plants regulate their stomata in response to environmental stimuli may have important implications for securing food production in a future climate. The stomata of most plants respond to elevated CO2 concentration by partial closing, but the magnitude of this response shows a large variation among species and ecotypes. Plants that substantially decrease stomatal conductance under elevated CO2 reduce their water consumption and increase their water-use efficiency. However, the genetic basis for inter- and intraspecific variation in responsiveness is poorly understood, as are the mechanisms for sensing and responding to CO2. In the current study, we have measured the short-term stomatal response to elevated CO2 in a population of Arabidopsis thaliana recombinant inbred lines (RILs) originating from a cross between two parental genotypes showing a large difference in stomatal responsiveness. Hence, this RIL population showed a broad range in stomatal responsiveness, ranging from a 10% to a 60% reduction of stomatal conductance following an increase in CO2 concentration from 400 to 800 ppm. Using quantitative trait locus (QTL) mapping we have identified two genetic loci involved in the stomatal response to elevated CO2. Potential candidate genes regulating the stomatal response will be discussed.
19.	Kohler, A., et al. (författare) High-throughput biochemical fingerprinting of Saccharomyces cerevisiae by Fourier transform infrared spectroscopy 2015 Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:2 Tidskriftsartikel (refereegranskat)abstract Single-channel optical density measurements of population growth are the dominant large scale phenotyping methodology for bridging the gene-function gap in yeast. However, a substantial amount of the genetic variation induced by single allele, single gene or double gene knock-out technologies fail to manifest in detectable growth phenotypes under conditions readily testable in the laboratory. Thus, new high-throughput phenotyping technologies capable of providing information about molecular level consequences of genetic variation are sorely needed. Here we report a protocol for high-throughput Fourier transform infrared spectroscopy (FTIR) measuring biochemical fingerprints of yeast strains. It includes high-throughput cultivation for FTIR spectroscopy, FTIR measurements and spectral pretreatment to increase measurement accuracy.We demonstrate its capacity to distinguish not only yeast genera, species and populations, but also strains that differ only by a single gene, its excellent signal-to-noise ratio and its relative robustness to measurement bias. Finally, we illustrated its applicability by determining the FTIR signatures of all viable Saccharomyces cerevisiae single gene knock-outs corresponding to lipid biosynthesis genes. Many of the examined knock-out strains showed distinct, highly reproducible FTIR phenotypes despite having no detectable growth phenotype. These phenotypes were confirmed by conventional lipid analysis and could be linked to specific changes in lipid composition. We conclude that the introduced protocol is robust to noise and bias, possible to apply on a very large scale, and capable of generating biologically meaningful biochemical fingerprints that are strain specific, even when strains lack detectable growth phenotypes. Thus, it has a substantial potential for application in the molecular functionalization of the yeast genome.
20.	Kvernebo-Sunnergren, Kjersti, 1974, et al. (författare) Hyperestrogenism Affects Adult Height Outcome in Growth Hormone Treated Boys With Silver-Russell Syndrome 2018 Ingår i: Frontiers in Endocrinology. - : Frontiers Media SA. - 1664-2392. ; 9 Tidskriftsartikel (refereegranskat)abstract Background: Intrauterine growth retardation and short stature are common features in Silver-Russell syndrome (SRS). Despite recombinant growth hormone (rGH) treatment, poor pubertal height gain, affecting adult height (AH), is common. This study investigated whether growth patterns and estrogen concentrations are associated with AH outcome in rGH treated SRS males. Methods: In this retrospective longitudinal single-center study, 11 males with SRS were classified as non-responders (NR = 6) or responders (R = 5), depending on AH adjusted for midparental height. Epigenetic analysis and longitudinal growth measures, including bone age, rGH related parameters, pubertal development, gonadotropins and estrogen concentrations, were analyzed until AH. Results: Pubarche before 9 years was only observed in one NR. At 10 years of age, there was no difference in gonadotropins between NR and R. However, estradiol (E2) concentrations at 10 years of age showed a strong association to AH adjusted for MPH (r = -0.78, p < 0.001). Serum E2 (pmol/L) was significantly higher in NR at ages 10 years [median (range) 2 (<2-5) vs. <2 (<2)], 12 years [23 (10-57) vs. 2 (<2-2)] and 14 years [77 (54-87) vs. 24 (<2-38)] but not at 16 years. Birth weight standard deviation score (SDS) was lower in NR [-4.1 (-4.7 to -2.1) vs. -2.7 (-3.3 to -1.7)]. Weight gain (SDS) until pubertal onset was greater in NR [2.4 (1.4-3.5) vs. 0.8 (-0.4 to 1.7)] and pubertal height gain (SDS) was lower in NR [-1.0 (-2.7-0.4) vs. 0.1 (-0.1 to 1.1)]. At AH, a number of NR and R had high E2 concentrations and small testes. Conclusion: Increased E2 concentrations at age 10, 12, and 14 years were associated to less pubertal height gain, thus affecting AH. Due to the small number of patients, the results need to be confirmed in larger cohorts. The finding of impaired testicular development stresses the need of hormonal evaluation as a complement to clinical and radiological assessment when predicting AH in males with SRS.
21.	Löfqvist, Chatarina, 1964, et al. (författare) Association of Retinopathy of Prematurity With Low Levels of Arachidonic Acid A Secondary Analysis of a Randomized Clinical Trial 2018 Ingår i: Jama Ophthalmology. - : American Medical Association (AMA). - 2168-6165. ; 136:3, s. 271-277 Tidskriftsartikel (refereegranskat)abstract IMPORTANCE Mice with oxygen-induced retinopathy fed matched diets except for omega-3 long-chain polyunsaturated fatty acids (LC-PUFAs) vs omega-6 LC-PUFAs demonstrate relative antiangiogenic and neuroprotective associations of omega-3 LC-PUFAs. However, supplementing preterm infants with LC-PUFAs has been inconsistent in reducing major preterm morbidities. However, few studies measured serum lipid levels after supplementation. OBJECTIVE To examine the associated risk of retinopathy of prematurity (ROP) from the levels of circulating omega-3 and omega-6 LC-PUFAs. DESIGN, SETTING, AND PARTICIPANTS This longitudinal clinical study was a further analysis of serum lipid levels from a randomized controlled trial cohort of 90 infants born at gestational age (GA) less than 28 weeks. From April 4, 2013, to September 22, 2015, cord blood samples, followed by venous blood samples, were obtained at birth and at 1, 7, 14, and 28 days after birth and then at postmenstrual age (PMA) 32, 36, and 40 weeks at the neonatal intensive care unit at Sahlgrenska University Hospital in Goteborg, Sweden. MAIN OUTCOMES AND MEASURES Serum phospholipid fatty acids were transmethylated and measured by gas chromatography-mass spectrometry. Mann-Whitney test, logistic regression Spearman rank correlation, and receiver operating characteristic curve analysis were used to compare differences between infants with no ROP and infants who developed ROP. RESULTS Serum levels from 78 infants (43 male [55%]; mean [SD] GA, 25.5 [1.4] weeks) with a known ROP outcome were evaluated. Lower area under the curve (AUC) of arachidonic acid (AA) (20: 4 omega-6) was seen in infants with a later diagnosis of ROP compared with infants with no ROP in the first month of life (mean, 34.05 [95% CI, 32.10-36.00] vs 37.15 [95% CI, 34.85-39.46]; P < .05). In addition, lower levels of AA at 32 weeks' PMA were seen in infants with later severe ROP compared with in those without ROP (mean, 7.06 [95% CI, 6.60-7.52] vs 8.74 [95% CI, 7.80-9.67]; P < .001). In logistic modeling, low postnatal serum levels of AA and GA at birth identified with a sensitivity greater than 90% of infants who developed ROP. CONCLUSIONS AND RELEVANCE Low postnatal levels of the omega-6 LC-PUFAs (AA) are strongly associated with ROP development. Evaluating postnatal AA fraction after birth in addition to GA may be useful for ROP prediction.
22.	Nilsson, Anders K., 1982, et al. (författare) Influence of Human Milk and Parenteral Lipid Emulsions on Serum Fatty Acid Profiles in Extremely Preterm Infants. 2019 Ingår i: JPEN - Journal of Parenteral and Enteral Nutrition. - : Wiley. - 0148-6071 .- 1941-2444. ; 43:1, s. 152-161 Tidskriftsartikel (refereegranskat)abstract Infants born prematurely are at risk of a deficiency in ω-6 and ω-3 long-chain polyunsaturated fatty acids (LC-PUFAs) arachidonic acid (AA) and docosahexaenoic acid (DHA). We investigated how fatty acids from breast milk and parenteral lipid emulsions shape serum LC-PUFA profiles in extremely preterm infants during early perinatal life.Ninety infants born < 28 weeks gestational age were randomized to receive parenteral lipids with or without the ω-3 LC-PUFAs eicosapentaenoic acid (EPA) and DHA (SMOFlipid: Fresenius Kabi, Uppsala, Sweden, or Clinoleic: Baxter Medical AB, Kista, Sweden, respectively). The fatty acid composition of infant serum phospholipids was determined from birth to postmenstrual age 40 weeks, and in mother's milk total lipids on postnatal day 7. Enteral and parenteral intake of LC-PUFAs was correlated with levels in infant serum.Infants administered parenteral ω-3 LC-PUFAs received 4.4 and 19.3 times more DHA and EPA, respectively, over the first 2 weeks of life. Parenteral EPA but not DHA correlated with levels in infant serum. We found linear relationships between dietary EPA and DHA and infant serum levels in the Clinoleic (Baxter Medical AB) group. The volume of administered SMOFlipid (Fresenius Kabi) was inversely correlated with serum AA, whereas Clinoleic (Baxter Medical AB) inversely correlated with serum EPA and DHA.There appears to be no or low correlation between the amount of DHA administered parenterally and levels measured in serum. Whether this observation reflects serum phospholipid fraction only or truly represents the amount of accreted DHA needs to be investigated. None of the parenteral lipid emulsions satisfactorily maintained high levels of both ω-6 and ω-3 LC-PUFAs in infant serum.
23.	Nilsson, Anders K., 1982, et al. (författare) Long-chain polyunsaturated fatty acids decline rapidly in milk from mothers delivering extremely preterm indicating the need for supplementation. 2018 Ingår i: Acta paediatrica. - : Wiley. - 1651-2227 .- 0803-5253. ; 107:6, s. 1020-1027 Tidskriftsartikel (refereegranskat)abstract Our aim was perform an in-depth analysis of the composition of fatty acids in milk from mothers delivering extremely preterm babies. We investigated longitudinal changes in milk fatty acid profiles and the relationship between several types of fatty acids, including omega-3 and omega-6.Milk samples were collected at three stages of lactation from 78 mothers who delivered at less than 28 weeks of pregnancy at the Sahlgrenska University Hospital, Gothenburg, Sweden, from April 2013 to September 2015. Fatty acid composition was analysed by gas chromatography-mass spectrometry.A reduction in long-chain polyunsaturated fatty acids (LCPUFAs) was observed during the lactation period. The concentrations of arachidonic acid and docosahexaenoic acid declined from medians of 0.34 to 0.22 mol% and 0.29 to 0.15 mol%, respectively, between postnatal day seven and a post-menstrual age of 40 weeks. Strong correlations were found between the intermediates of several classes of fatty acids, including omega-3, omega-6 and omega-9.A rapid reduction in LCPUFA content in the mother's milk during the lactation period emphasises the importance of fatty acid supplementation to infants born extremely preterm, at least during the period corresponding to the third trimester, when rapid development of the brain and adipose tissue require high levels of LCPUFAs. This article is protected by copyright. All rights reserved.
24.	Nilsson, Anders K., 1982, et al. (författare) The pht4;1-3 mutant line contains a loss of function allele in the fatty acid desaturase 7 gene caused by a remnant inactivated selection marker- a cautionary tale 2017 Ingår i: PeerJ. - : PeerJ. - 2167-8359. ; 5 Tidskriftsartikel (refereegranskat)abstract © 2017 Nilsson and Andersson. Astriking and unexpected biochemical phenotype was found in an insertion mutant line in the model plant Arabidopsis thaliana. One of two investigated insertion mutant lines in the gene encoding the phosphate transporter PHT4;1 demonstrated a prominent loss of trienoic fatty acids, whereas the other insertion line was indistinguishable from wild type in this aspect. We demonstrate that the loss of trienoic fatty acids was due to a remnant inactive negative selection marker gene in this particular transposon tagged line, pht4;1-3. This constitutes a cautionary tale that warns of the importance to confirm the loss of this type of selection markers and the importance of verifying the relationship between a phenotype and genotype by more than one independent mutant line or alternatively genetic complementation.
25.	Selander, Erik, 1973, et al. (författare) Copepods drive large-scale trait-mediated effects in marine plankton 2019 Ingår i: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 5 Tidskriftsartikel (refereegranskat)abstract Copyright © 2019 The Authors. Fear of predation may influence food webs more than actual predation. However, the mechanisms and magnitude of nonconsumptive predator effects are largely unknown in unicellular-dominated food webs such as marine plankton. We report a general mechanism of chemically induced predator effects in marine plankton. Copepods, the most abundant zooplankton in the oceans, imprint seawater with unique polar lipids—copepodamides—which trigger toxin production and bioluminescence in harmful dinoflagellates. We show that copepodamides also elicit defensive traits in other phytoplankton, inducing the harmful algal bloom-forming diatom Pseudo-nitzschia seriata to produce 10 times more toxins, and colony-forming diatoms to decrease colony size by half. A 1-year study in the northeast Atlantic revealed that natural copepodamide concentrations are high enough to induce harmful algal toxins and size reduction in dominant primary producers when copepods are abundant. We conclude that copepodamides will structure marine plankton toward smaller, more defended life forms on basin-wide scales.
26.	Selander, Erik, 1973, et al. (författare) Predator lipids induce paralytic shellfish toxins in bloom-forming algae 2015 Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 112:20, s. 6395-6400 Tidskriftsartikel (refereegranskat)abstract Interactions among microscopic planktonic organisms underpin the functioning of open ocean ecosystems. With few exceptions, these organisms lack advanced eyes and thus rely largely on chemical sensing to perceive their surroundings. However, few of the signaling molecules involved in interactions among marine plankton have been identified. We report a group of eight small molecules released by copepods, the most abundant zooplankton in the sea, which play a central role in food webs and biogeochemical cycles. The compounds, named copepodamides, are polar lipids connecting taurine via an amide to isoprenoid fatty acid conjugate of varying composition. The bloom-forming dinoflagel-late Alexandrium minutum responds to pico- to nanomolar concentrations of copepodamides with up to a 20-fold increase in production of paralytic shellfish toxins. Different copepod species exude distinct copepodamide blends that contribute to the species-specific defensive responses observed in phytoplankton. The signaling system described here has far reaching implications for marine ecosystems by redirecting grazing pressure and facilitating the formation of large scale harmful algal blooms.
27.	Ulmann, L., et al. (författare) Microalgal Fatty Acids and Their Implication in Health and Disease 2017 Ingår i: Mini-Reviews in Medicinal Chemistry. - : Bentham Science Publishers Ltd.. - 1389-5575. ; 17:12, s. 1112-1123 Tidskriftsartikel (refereegranskat)abstract Background: The fatty acids of seed plants and microalgae stored in triglyceride are all produced in the plastid and incorporated into triglycerides by a complex biochemical exchange between the plastid envelope and the endoplasmic reticulum. The oils of seed plants provide the basis for vegetal fat production and the microalgal fats represent an important part of the basal food web of the marine environment. The health-promoting properties of these various sources of fats and in particular the long-chain polyunsaturated fatty acids of marine microalgae are widely recognized. The omega-3 fatty acids are known to have benefits on health and disease. Indeed, alpha-linolenic, eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) are linked to the regulation of mechanisms involved in numerous biological functions associated with cardiovascular disease and cancer prevention. Most EPA and DHA sources for human nutrition are provided by decreasing global stocks of fish. This is one of the reasons why industrial research has been directed towards more sustainable sources of these "marine" lipids. The synthesis of fatty acids and triglycerides are in many respects similar in higher plants and marine algae, but there are also important differences. Conclusion: This mini-review covers the biochemistry of fatty acid and lipid synthesis in marine microalgae, and the potential health impact of the different fats is also discussed.
28.	Yin, Congfei, et al. (författare) Phosphatidylcholine is transferred from chemically-defined liposomes to chloroplasts through proteins of the chloroplast outer envelope membrane 2015 Ingår i: Febs Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 589:1, s. 177-181 Tidskriftsartikel (refereegranskat)abstract Chloroplasts maintain their lipid balance through a tight interplay with the endoplasmic reticulum (ER). The outer envelope membrane of chloroplasts contains a large proportion of the phospholipid phosphatidylcholine (PC), which is synthesized in the ER and also a possible precursor for thylakoid galactolipids. The mechanism for PC transport from the ER to chloroplasts is not known. Using isolated chloroplasts and liposomes containing radiolabeled PC we investigated non-vesicular transport of PC in vitro. PC uptake in chloroplasts was time and temperature dependent, but nucleotide independent. Increased radius of liposomes stimulated PC uptake, and protease treatment of the chloroplasts impaired PC uptake. This implies that the chloroplast outer envelopes contains an exposed proteinaceous machinery for the uptake of PC from closely apposed membranes.

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