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1.	Arias, Carolina, et al. (author) Nuclear proteome analysis of Chlamydomonas with response to CO2 limitation 2020 In: Algal Research. - : Elsevier. - 2211-9264. ; 46 Journal article (peer-reviewed)abstract Chlamydomonas reinhardtii is a unicellular green alga that can survive at a wide range of inorganic carbon (Ci) concentrations by regulating the activity of a CO2-concentrating mechanism (CCM) as well as other cellular functions. Under CO2 limited conditions, C. reinhardtii cells display a wide range of adaptive responses including changes in photosynthetic electron transport, mitochondria localization in the cells, the structure of the pyrenoid starch sheath, and primary metabolism. In addition to these functional and structural changes, gene and protein expression are also affected. Several physiological aspects of the CO2 response mechanism have been studied in detail. However, the regulatory components (transcription factors and transcriptional regulators) involved in this process are not fully characterized. Here we report a comprehensive analysis of the C. reinhardtii nuclear proteome using liquid chromatography electrospray ionization spectrometry (LC-ESI-MS). The study aims to identify the proteins that govern adaptation to varying CO2 concentrations in Chlamydomonas. The nuclear proteome of C. reinhardtii cells grown in the air at high (5%) and low (0.04%) CO2 concentrations were analyzed. Using this approach, we identified 1378 proteins in total, including 90 putative transcription factors and 27 transcriptional regulators. Characterization of these new regulatory components could shed light on the molecular mechanisms underlying acclimation to CO2 stress.
2.	Bag, Pushan, 1993-, et al. (author) Direct energy transfer from photosystem II to photosystem I confers winter sustainability in Scots Pine 2020 In: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 11:1 Journal article (peer-reviewed)abstract Evergreen conifers in boreal forests can survive extremely cold (freezing) temperatures during long dark winter and fully recover during summer. A phenomenon called "sustained quenching" putatively provides photoprotection and enables their survival, but its precise molecular and physiological mechanisms are not understood. To unveil them, here we have analyzed seasonal adjustment of the photosynthetic machinery of Scots pine (Pinus sylvestris) trees by monitoring multi-year changes in weather, chlorophyll fluorescence, chloroplast ultrastructure, and changes in pigment-protein composition. Analysis of Photosystem II and Photosystem I performance parameters indicate that highly dynamic structural and functional seasonal rearrangements of the photosynthetic apparatus occur. Although several mechanisms might contribute to 'sustained quenching' of winter/early spring pine needles, time-resolved fluorescence analysis shows that extreme down-regulation of photosystem II activity along with direct energy transfer from photosystem II to photosystem I play a major role. This mechanism is enabled by extensive thylakoid destacking allowing for the mixing of PSII with PSI complexes. These two linked phenomena play crucial roles in winter acclimation and protection. Evergreen conifers rely on 'sustained quenching' to protect their photosynthetic machinery during long, cold winters. Here, Bag et al. show that direct energy transfer (spillover) from photosystem II to photosystem I triggered by loss of grana stacking in chloroplast is the major component of sustained quenching in Scots pine.
3.	Bajracharya, Suman, et al. (author) Advances in cathode designs and reactor configurations of microbial electrosynthesis systems to facilitate gas electro-fermentation 2022 In: Bioresource Technology. - : Elsevier. - 0960-8524 .- 1873-2976. ; 354 Journal article (peer-reviewed)abstract In gas fermentation, a range of chemolithoautotrophs fix single-carbon (C1) gases (CO2 and CO) when H2 or other reductants are available. Microbial electrosynthesis (MES) enables CO2 reduction by generating H2 or reducing equivalents with the sole input of renewable electricity. A combined approach as gas electro-fermentation is attractive for the sustainable production of biofuels and biochemicals utilizing C1 gases. Various platform compounds such as acetate, butyrate, caproate, ethanol, butanol and bioplastics can be produced. However, technological challenges pertaining to the microbe-material interactions such as poor gas-liquid mass transfer, low biomass and biofilm coverage on cathode, low productivities still exist. We are presenting a review on latest developments in MES focusing on the configuration and design of cathodes that can address the challenges and support the gas electro-fermentation. Overall, the opportunities for advancing CO and CO2-based biochemicals and biofuels production in MES with suitable cathode/reactor design are prospected.
4.	Bajracharya, Suman, et al. (author) Chapter 12 - Advances in gas fermentation processes 2022 In: Current Developments in Biotechnology and Bioengineering. - : Elsevier. - 9780323911672 ; , s. 321-351 Book chapter (other academic/artistic)abstract Microbial metabolism enables the sustainable synthesis of fuels and chemicals from gaseous substrates (H2, CO, and CO2), thus drastically diminishing the carbon load in the atmosphere. Various value-added biochemicals and biofuels, such as acetate, methane, ethanol, butanol, butyrate, caproate, and bioplastics, have been produced during the conversion of syngas or H2/CO2, using a variety of microorganisms as biocatalysts. Gas fermentation processes using acetogenic and methanogenic organisms are being extensively investigated. This chapter provides an overview of microbial CO and CO2 conversion technology, with an emphasis on recent developments and integration with renewable electricity for the generation of H2 or other forms of electron donors. A discussion on technological challenges in gas fermentation addresses issues, such as poor mass transfer, low microbial biomass, and low productivity. It also presents possible solutions based on the latest advances in bioelectrochemical processes including microbial gas electrofermentation. Finally, the chapter includes a sustainability analysis of the process and includes a brief update on commercially established companies operating gas fermentation systems. Overall, an integrated approach combining gas fermentation and renewable electricity offers an opportunity for the development of CO and CO2- based biochemical and biofuel production at commercial scale.
5.	Bajracharya, Suman, et al. (author) Dual cathode configuration and headspace gas recirculation for enhancing microbial electrosynthesis using Sporomusa ovata 2022 In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 287, Part 3 Journal article (peer-reviewed)abstract High-rate production of acetate and other value-added products from the reduction of CO2 in microbial electrosynthesis (MES) using acetogens can be achieved with high reducing power where H2 appears as a key electron mediator. H2 evolution using metal cathodes can enhance the availability of H2 to support high-rate microbial reduction of CO2. Due to the low solubility of H2, the availability of H2 remains limited to the bacteria. In this study, we investigated the performances of Sporomusa ovata for CO2 reduction when dual cathodes were used together in an MES, one was regular carbon cathode, and the other was a titanium mesh that allows higher hydrogen evolution. The dual cathode configuration was investigated in two sets of MES, one set had the usual S. ovata inoculated graphite rod, and another set had a synthetic biofilm-imprinted carbon cloth. Additionally, the headspace gas in MES was recirculated to increase the H2 availability to the bacteria in suspension. High-rate CO2 reduction was observed at −0.9 V vs Ag/AgCl with dual cathode configuration as compared to single cathodes. High titers of acetate (up to ∼11 g/L) with maximum instantaneous rates of 0.68–0.7 g/L/d at −0.9 V vs Ag/AgCl were observed, which are higher than the production rates reported in literatures for S. ovata using MES with surface modified cathodes. A high H2 availability supported the high-rate acetate production from CO2 with diminished electricity input.
6.	Bajracharya, Suman, et al. (author) Microbial Electrosynthesis Using 3D Bioprinting of Sporomusa ovata on Copper, Stainless-Steel, and Titanium Cathodes for CO2 Reduction 2023 In: Fermentation. - : MDPI. - 2311-5637. ; 10:1 Journal article (peer-reviewed)abstract Acetate can be produced from carbon dioxide (CO2) and electricity using bacteria at the cathode of microbial electrosynthesis (MES). This process relies on electrolytically-produced hydrogen (H2). However, the low solubility of H2 can limit the process. Using metal cathodes to generate H2 at a high rate can improve MES. Immobilizing bacteria on the metal cathode can further proliferate the H2 availability to the bacteria. In this study, we investigated the performances of 3D bioprinting of Sporomusa ovata on three metal meshes—copper (Cu), stainless steel (SS), and titanium (Ti), when used individually as a cathode in MES. Bacterial cells were immobilized on the metal using a 3D bioprinter with alginate hydrogel ink. The bioprinted Ti mesh exhibited higher acetate production (53 ± 19 g/m2/d) at −0.8 V vs. Ag/AgCl as compared to other metal cathodes. More than 9 g/L of acetate was achieved with bioprinted Ti, and the least amount was obtained with bioprinted Cu. Although all three metals are known for catalyzing H2 evolution, the lower biocompatibility and chemical stability of Cu hampered its performance. Stable and biocompatible Ti supported the bioprinted S. ovata effectively. Bioprinting of synthetic biofilm on H2-evolving metal cathodes can provide high-performing and robust biocathodes for further application of MES.
7.	Beer, Tomasz M, et al. (author) Enzalutamide in metastatic prostate cancer before chemotherapy 2014 In: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 371:5, s. 33-424 Journal article (peer-reviewed)abstract BACKGROUND: Enzalutamide is an oral androgen-receptor inhibitor that prolongs survival in men with metastatic castration-resistant prostate cancer in whom the disease has progressed after chemotherapy. New treatment options are needed for patients with metastatic prostate cancer who have not received chemotherapy, in whom the disease has progressed despite androgen-deprivation therapy.METHODS: In this double-blind, phase 3 study, we randomly assigned 1717 patients to receive either enzalutamide (at a dose of 160 mg) or placebo once daily. The coprimary end points were radiographic progression-free survival and overall survival.RESULTS: The study was stopped after a planned interim analysis, conducted when 540 deaths had been reported, showed a benefit of the active treatment. The rate of radiographic progression-free survival at 12 months was 65% among patients treated with enzalutamide, as compared with 14% among patients receiving placebo (81% risk reduction; hazard ratio in the enzalutamide group, 0.19; 95% confidence interval [CI], 0.15 to 0.23; P<0.001). A total of 626 patients (72%) in the enzalutamide group, as compared with 532 patients (63%) in the placebo group, were alive at the data-cutoff date (29% reduction in the risk of death; hazard ratio, 0.71; 95% CI, 0.60 to 0.84; P<0.001). The benefit of enzalutamide was shown with respect to all secondary end points, including the time until the initiation of cytotoxic chemotherapy (hazard ratio, 0.35), the time until the first skeletal-related event (hazard ratio, 0.72), a complete or partial soft-tissue response (59% vs. 5%), the time until prostate-specific antigen (PSA) progression (hazard ratio, 0.17), and a rate of decline of at least 50% in PSA (78% vs. 3%) (P<0.001 for all comparisons). Fatigue and hypertension were the most common clinically relevant adverse events associated with enzalutamide treatment.CONCLUSIONS: Enzalutamide significantly decreased the risk of radiographic progression and death and delayed the initiation of chemotherapy in men with metastatic prostate cancer. (Funded by Medivation and Astellas Pharma; PREVAIL ClinicalTrials.gov number, NCT01212991.).
8.	Berntsson, Elina, et al. (author) Characterization of Uranyl (UO22+) Ion Binding to Amyloid Beta (Aβ) Peptides : Effects on Aβ Structure and Aggregation 2023 In: ACS Chemical Neuroscience. - 1948-7193. ; 14:15, s. 2618-2633 Journal article (peer-reviewed)abstract Uranium (U) is naturally present in ambient air, water, and soil, and depleted uranium (DU) is released into the environment via industrial and military activities. While the radiological damage from U is rather well understood, less is known about the chemical damage mechanisms, which dominate in DU. Heavy metal exposure is associated with numerous health conditions, including Alzheimer’s disease (AD), the most prevalent age-related cause of dementia. The pathological hallmark of AD is the deposition of amyloid plaques, consisting mainly of amyloid-β (Aβ) peptides aggregated into amyloid fibrils in the brain. However, the toxic species in AD are likely oligomeric Aβ aggregates. Exposure to heavy metals such as Cd, Hg, Mn, and Pb is known to increase Aβ production, and these metals bind to Aβ peptides and modulate their aggregation. The possible effects of U in AD pathology have been sparsely studied. Here, we use biophysical techniques to study in vitro interactions between Aβ peptides and uranyl ions, UO22+, of DU. We show for the first time that uranyl ions bind to Aβ peptides with affinities in the micromolar range, induce structural changes in Aβ monomers and oligomers, and inhibit Aβ fibrillization. This suggests a possible link between AD and U exposure, which could be further explored by cell, animal, and epidemiological studies. General toxic mechanisms of uranyl ions could be modulation of protein folding, misfolding, and aggregation.
9.	Berntsson, Elina, et al. (author) Lithium ions display weak interaction with amyloid-beta (Aβ) peptides and have minor effects on their aggregation 2021 In: Acta Biochimica Polonica. - : Polskie Towarzystwo Biochemiczne (Polish Biochemical Society). - 0001-527X .- 1734-154X. ; 68:2, s. 169-179 Journal article (peer-reviewed)abstract Alzheimer’s disease (AD) is an incurable disease and the main cause of age-related dementia worldwide, despite decades of research. Treatment of AD with lithium (Li) has shown promising results, but the underlying mechanism is unclear. The pathological hallmark of AD brains is deposition of amyloid plaques, consisting mainly of amyloid-β (Aβ) peptides aggregated into amyloid fibrils. The plaques contain also metal ions of e.g. Cu, Fe, and Zn, and such ions are known to interact with Aβ peptides and modulate their aggregation and toxicity. The interactions between Aβ peptides and Li+ions have however not been well investigated. Here, we use a range of biophysical techniques to characterize in vitro interactions between Aβ peptides and Li+ions. We show that Li+ions display weak and non-specific interactions with Aβ peptides, and have minor effects on Aβ aggregation. These results indicate that possible beneficial effects of Li on AD pathology are not likely caused by direct interactions between Aβ peptides and Li+ions.
10.	Berntsson, Elina, et al. (author) Residue-specific binding of Ni(II) ions influences the structure and aggregation of amyloid beta (Aβ) peptides 2023 In: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 13:1 Journal article (peer-reviewed)abstract Alzheimer's disease (AD) is the most common cause of dementia worldwide. AD brains display deposits of insoluble amyloid plaques consisting mainly of aggregated amyloid-β (Aβ) peptides, and Aβ oligomers are likely a toxic species in AD pathology. AD patients display altered metal homeostasis, and AD plaques show elevated concentrations of metals such as Cu, Fe, and Zn. Yet, the metal chemistry in AD pathology remains unclear. Ni(II) ions are known to interact with Aβ peptides, but the nature and effects of such interactions are unknown. Here, we use numerous biophysical methods-mainly spectroscopy and imaging techniques-to characterize Aβ/Ni(II) interactions in vitro, for different Aβ variants: Aβ(1-40), Aβ(1-40)(H6A, H13A, H14A), Aβ(4-40), and Aβ(1-42). We show for the first time that Ni(II) ions display specific binding to the N-terminal segment of full-length Aβ monomers. Equimolar amounts of Ni(II) ions retard Aβ aggregation and direct it towards non-structured aggregates. The His6, His13, and His14 residues are implicated as binding ligands, and the Ni(II)·Aβ binding affinity is in the low µM range. The redox-active Ni(II) ions induce formation of dityrosine cross-links via redox chemistry, thereby creating covalent Aβ dimers. In aqueous buffer Ni(II) ions promote formation of beta sheet structure in Aβ monomers, while in a membrane-mimicking environment (SDS micelles) coil-coil helix interactions appear to be induced. For SDS-stabilized Aβ oligomers, Ni(II) ions direct the oligomers towards larger sizes and more diverse (heterogeneous) populations. All of these structural rearrangements may be relevant for the Aβ aggregation processes that are involved in AD brain pathology.
11.	Datta, Kanan K., et al. (author) Light cone effect on the reionization 21-cm signal - II. Evolution, anisotropies and observational implications 2014 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 442:2, s. 1491-1506 Journal article (peer-reviewed)abstract Measurements of the H i 21-cm power spectra from the reionization epoch will be influenced by the evolution of the signal along the line-of-sight direction of any observed volume. We use numerical as well as seminumerical simulations of reionization in a cubic volume of 607 Mpc across to study this so-called light-cone effect on the H i 21-cm power spectrum. We find that the light-cone effect has the largest impact at two different stages of reionization: one when reionization is similar to 20 per cent and other when it is similar to 80 per cent completed. We find a factor of similar to 4 amplification of the power spectrum at the largest scale available in our simulations. We do not find any significant anisotropy in the 21-cm power spectrum due to the light-cone effect. We argue that for the power spectrum to become anisotropic, the light-cone effect would have to make the ionized bubbles significantly elongated or compressed along the line of sight, which would require extreme reionization scenarios. We also calculate the two-point correlation functions parallel and perpendicular to the line of sight and find them to differ. Finally, we calculate an optimum frequency bandwidth below which the light-cone effect can be neglected when extracting power spectra from observations. We find that if one is willing to accept a 10 per cent error due to the light-cone effect, the optimum frequency bandwidth for k = 0.056 Mpc(-1) is similar to 7.5 MHz. For k = 0.15 and 0.41 Mpc(-1), the optimum bandwidth is similar to 11 and similar to 16 MHz, respectively.
12.	Erlinge, David, et al. (author) Clopidogrel metaboliser status based on point-of-care CYP2C19 genetic testing in patients with coronary artery disease 2014 In: Thrombosis and Haemostasis. - 0340-6245 .- 2567-689X. ; 111:5, s. 943-950 Journal article (peer-reviewed)abstract We compared results obtained with the Nanosphere Verigene (R) System, a novel point-of-care (POC) genetic test capable of analysing 11, CYP2C19 variants within 3 hours, to an established, validated genotyping method (Affymetrix (TM) DMET+; reference assay) for identifying extensive and reduced metabolisers of clopidogrel. Based on genotyping, patients (N=82) with stable coronary artery disease on clopidogrel 75 mg daily were defined as extensive metabolisers (1/1, 1/17,17/17), reduced metabolisers (1/2,1/8,2/2,2/3), or of indeterminate metaboliser status (2/17). Pharmacokinetic exposure to clopidogrel's active metabolite and pharmacodynamic measures with P2Y12 reaction units (PRU) (VerifyNow (R) P2Y12 assay), and VASP PRI (PRI) were also assessed. There was a 99.9% overall; concordance of marker-level data between the Nanosphere Verigene and DMET+ systems in identifying the CYP2C19 variants and 100% agreement in classifying the patients as extensive (n=59) or reduced metabolisers (n=15). Extensive metabolisers had significantly higher active metabolite exposure than reduced metabolisers (LS means 12.6 ngh/ml vs 7.7 ngh/ml; p<0.001). Extensive metabolisers also had lower PRU (LS means 158 vs 212; p=0.003) and VASP PRI (LS means 48% vs 63%, p=0.01) compared to reduced metabolisers. Rates of high on-treatment platelet reactivity were higher in reduced metabolisers compared to extensive metabolisers (VASP PRI >= 50%: 79% vs 47%; PRU >235: 33% vs 16%). The Nanosphere Verigene CBS system identified 11 CYP2C19 alleles in less than 3 hours with a high degree of accuracy when compared to a conventional method, and was further validated against pharmacokinetic and pharmacodynamic phenotypes.
13.	Erlinge, David, et al. (author) Point-of-Care Genetic Testing of Eleven CYP2C19 Single Nucleotide Polymorphisms Identifies Extensive and Reduced Metabolizers of Clopidogrel With High Accuracy in Patients With Coronary Artery Disease 2012 In: Journal of the American College of Cardiology. - : Elsevier BV. - 0735-1097 .- 1558-3597. ; 60:17, s. B211-B212 Journal article (other academic/artistic)
14.	Gurbel, Paul A., et al. (author) The effect of CYP2C19 gene polymorphisms on the pharmacokinetics and pharmacodynamics of prasugrel 5-mg, prasugrel 10-mg and clopidogrel 75-mg in patients with coronary artery disease 2014 In: Thrombosis and Haemostasis. - : Schattauer. - 0340-6245 .- 2567-689X. ; 112:3, s. 589-597 Journal article (peer-reviewed)abstract CYP2C19 genotype has been shown to impact response to clopidogrel 75-mg but not prasugrel 10-mg. Here, we assessed effects of CYP2C19 metaboliser status on pharmacokinetics (PK) and pharmacodynamic (PD) responses to prasugrel 5-mg and 10-mg and clopidogrel 75-mg using data from two PK/PD studies in stable coronary artery disease (CAD) patients (GENERATIONS and FEATHER). Active metabolite concentrations (area under the curve, AUC([0-tlast])), maximum platelet aggregation (MPA) measured by light transmission aggregometry, vasodilator-stimulated phosphoprotein platelet reactivity index, and VerifyNow P2Y12-platelet reaction units (VN-PRU) were analysed by CYP2C19-predicted phenotype (extensive metaboliser [EM; N=154], 2-8 non-carriers, vs reduced metaboliser [RM; N=41],2-8 carriers/*17 non-carriers). AUC((0-tlast)) was unaffected by metaboliser status for prasugrel 5-mg and 10-mg (geometric mean EM/RM ratios 1.00, 95% confidence interval [Cl]: 0.86,1.17, p>0.99; and 0.97, 95% CI:0.85,1.12, p=0.71, respectively), but was lower among RMs receiving clopidogrel 75-mg (1.37, 95% CI:1.14,1.65, p<0.001). Platelet reactivity was not significantly affected by CYP2C19 metaboliser status for prasugrel 5-mg, or for prasugrel 10-mg by MPA and VN-PRU, but for clopidogrel 75-mg was significantly higher in reduced metabolisers (all measures p<0.01). Prasugrel 10-mg showed greater antiplatelet effects vs clopidogrel 75-mg (all comparisons p<0.001). Prasugrel 5-mg showed greater antiplatelet effects vs clopidogrel 75-mg in RMs (all p<0.001), and comparable effects in EMs (all p >= 0.37). In contrast to clopidogrel, prasugrel active metabolite PK was not influenced by CYP2C19 genotype. Antiplatelet effect for prasugrel 10-mg was greater irrespective of metaboliser status and for prasugrel 5-mg was greater for RMs and comparable for EMs as compared to clopidogrel 75-mg.
15.	Hultmark, Sandra, 1994, et al. (author) Vitrification of octonary perylene mixtures with ultralow fragility 2021 In: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 7:29 Journal article (peer-reviewed)abstract Strong glass formers with a low fragility are highly sought-after because of the technological importance of vitrification. In the case of organic molecules and polymers, the lowest fragility values have been reported for single-component materials. Here, we establish that mixing of organic molecules can result in a marked reduction in fragility. Individual bay-substituted perylene derivatives display a high fragility of more than 70. Instead, slowly cooled perylene mixtures with more than three components undergo a liquid-liquid transition and turn into a strong glass former. Octonary perylene mixtures display a fragility of 13 +/- 2, which not only is a record low value for organic molecules but also lies below values reported for the strongest known inorganic glass formers. Our work opens an avenue for the design of ultrastrong organic glass formers, which can be anticipated to find use in pharmaceutical science and organic electronics.
16.	Jampala, Annie Modestra, et al. (author) Bioelectrochemical treatment of acid mine drainage: Microbiome synergy influences sulfidogenesis and acetogenesis 2024 In: Sustainable Chemistry for the Environment. - : Elsevier. - 2949-8392. ; 6 Journal article (peer-reviewed)abstract Bioelectrochemical systems (BES) are emerging as potential technologies that can remediate acid mine drainage (AMD) by cathodic reduction of sulfates to metal sulfides. This study evaluated bioelectrochemical remediation of sulfate rich AMD at two applied cathode potentials; BES-1: −1.0 V and BES-2: −0.8 V. Sulfate reducing bacteria were selectively enriched to be used as biocatalyst in BES. Initially, lactate was fed as carbon source and switched to chemolithoautotrophy with only CO2-fed conditions. Both BESs were operated at 3±0.2 g/l of sulfate with synthetic AMD (SAMD) fed first, and gradually changed to 50% AMD from mining site with 50% SAMD. Sulfate reduction was relatively higher with BES-1: 82% than BES-2: 76% coupled with sulfidogenesis. Interestingly, acetogenesis (BES-1: 2.12±0.2 g/l, BES-2: 1.9±0.2 g/l) was also noticed with high reduction currents (BES-1&2: >-70 mA). Microbiome community analysis revealed the dominant presence of sulfate reducers, acetogens, syntrophic bacteria and Methanobacterium, probing microbial synergy aiding sulfate reduction. An added advantage was the iron-sulfide (FeS) particles formation on cathode, which might have contributed to increased reduction currents. This study reveals insights into microbial synergy for autotrophic sulfate reduction within mixed microbiome communities along with the impact of FeS particles as conducive facilitator for electron transfer in BES, thereby enhancing electrosynthetic acetate production.
17.	Merckx, Vincent S. F. T., et al. (author) Evolution of endemismon a young tropical mountain 2015 In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 524:7565, s. 347- Journal article (peer-reviewed)abstract Tropical mountains are hot spots of biodiversity and endemism(1-3), but the evolutionary origins of their unique biotas are poorly understood(4). In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of these communities(5). Also, it is debated whether mountain endemics mostly originate from local lowland taxa, or from lineages that reach the mountain by long-range dispersal from cool localities elsewhere(6). Here we investigate the evolutionary routes to endemism by sampling an entire tropical mountain biota on the 4,095-metre-high Mount Kinabalu in Sabah, East Malaysia. We discover that most of its unique biodiversity is younger than the mountain itself (6 million years), and comprises a mix of immigrant pre-adapted lineages and descendants from local lowland ancestors, although substantial shifts from lower to higher vegetation zones in this latter group were rare. These insights could improve forecasts of the likelihood of extinction and 'evolutionary rescue'(7) in montane biodiversity hot spots under climate change scenarios.
18.	Neupane, Suman, et al. (author) The Hedyotis-Oldenlandia complex (Rubiaceae: Spermacoceae) in Asia and the Pacific : Phylogeny revisited with new generic delimitations 2015 In: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 64:2, s. 299-322 Journal article (peer-reviewed)abstract Hedyotis and related genera (here called the Hedyotis-Oldenlandia complex) are highly debated groups in the Rubiaceae family with no consensus to date on their generic delimitations. The present study focuses on Asian-Pacific taxa from these groups and aims at resolving taxonomic inconsistencies by describing monophyletic genera within the complex. The generic circumscriptions presented in our study are based on the phylogenetic trees of nuclear (ITS, ETS) and plastid (petD, rps16) sequence data inferred using Bayesian and maximum likelihood methods. Morphological key features of the group such as habit, fruit type, seed form, and pollen type are studied and compared with the phylogeny to characterize the clades. Based on these results, the Asian-Pacific members are placed in 14 monophyletic groups across the Hedyotis-Oldenlandia complex. Of these, we accept and circumscribe 13 monophyletic genera: Debia, Dentella, Dimetia, Edrastima, Exallage, Hedyotis, Involucrella, Kadua, Kohautia, Leptopetalum, Neanotis, Oldenlandia, and Scleromitrion. Two of these, Debia and Involucrella, are here described as new genera.
19.	Paul, Suman, et al. (author) 13C- and 15N-labeling of amyloid-β and inhibitory peptides to study their interaction via nanoscale infrared spectroscopy 2023 In: Communications Chemistry. - 2399-3669. ; 6:1 Journal article (peer-reviewed)abstract Interactions between molecules are fundamental in biology. They occur also between amyloidogenic peptides or proteins that are associated with different amyloid diseases, which makes it important to study the mutual influence of two polypeptides on each other's properties in mixed samples. However, addressing this research question with imaging techniques faces the challenge to distinguish different polypeptides without adding artificial probes for detection. Here, we show that nanoscale infrared spectroscopy in combination with C-13, N-15-labeling solves this problem. We studied aggregated amyloid-& beta; peptide (A & beta;) and its interaction with an inhibitory peptide (NCAM1-PrP) using scattering-type scanning near-field optical microscopy. Although having similar secondary structure, labeled and unlabeled peptides could be distinguished by comparing optical phase images taken at wavenumbers characteristic for either the labeled or the unlabeled peptide. NCAM1-PrP seems to be able to associate with or to dissolve existing A & beta; fibrils because pure A & beta; fibrils were not detected after mixing. Interactions of proteins or polypeptides with different secondary structures can be studied in a mixture by nanoscale infrared spectroscopy, however, this technique remains challenging for polypeptides with similar secondary structures. Here, the authors demonstrate clear discrimination of two polypeptides from a mixture by scattering-type scanning near-field optical microscopy when one of the components is labeled with C-13- and N-15-isotopes.
20.	Pawlak, Krzysztof, et al. (author) On the PsbS-induced quenching in the plant major light-harvesting complex LHCII studied in proteoliposomes 2020 In: Photosynthesis Research. - : Springer Science and Business Media LLC. - 0166-8595 .- 1573-5079. ; 144:2, s. 195-208 Journal article (peer-reviewed)abstract Non-photochemical quenching (NPQ) in photosynthetic organisms provides the necessary photoprotection that allows them to cope with largely and quickly varying light intensities. It involves deactivation of excited states mainly at the level of the antenna complexes of photosystem II using still largely unknown molecular mechanisms. In higher plants the main contribution to NPQ is the so-called qE-quenching, which can be switched on and off in a few seconds. This quenching mechanism is affected by the low pH-induced activation of the small membrane protein PsbS which interacts with the major light-harvesting complex of photosystem II (LHCII). We are reporting here on a mechanistic study of the PsbS-induced LHCII quenching using ultrafast time-resolved chlorophyll (Chl) fluorescence. It is shown that the PsbS/LHCII interaction in reconstituted proteoliposomes induces highly effective and specific quenching of the LHCII excitation by a factor >= 20 via Chl-Chl charge-transfer (CT) state intermediates which are weakly fluorescent. Their characteristics are very broad fluorescence bands pronouncedly red-shifted from the typical unquenched LHCII fluorescence maximum. The observation of PsbS-induced Chl-Chl CT-state emission from LHCII in the reconstituted proteoliposomes is highly reminiscent of the in vivo quenching situation and also of LHCII quenching in vitro in aggregated LHCII, indicating a similar quenching mechanism in all those situations. The PsbS mutant lacking the two proton sensing Glu residues induced significant, but much smaller, quenching than wild type. Added zeaxanthin had only minor effects on the yield of quenching in the proteoliposomes. Overall our study shows that PsbS co-reconstituted with LHCII in liposomes represents an excellent in vitro model system with characteristics that are reflecting closely the in vivo qE-quenching situation.
21.	Schumann, Tobias, et al. (author) Plant Growth under Natural Light Conditions Provides Highly Flexible Short-Term Acclimation Properties toward High Light Stress 2017 In: Frontiers in Plant Science. - : FRONTIERS MEDIA SA. - 1664-462X. ; 8 Journal article (peer-reviewed)abstract Efficient acclimation to different growth light intensities is essential for plant fitness. So far, most studies on light acclimation have been conducted with plants grown under different constant light regimes, but more recent work indicated that acclimation to fluctuating light or field conditions may result in different physiological properties of plants. Thale cress (Arabidopsis thaliana) was grown under three different constant light intensities (LL: 25μmol photons m-2 s-1; NL: 100μmol photons m-2 s-1; HL: 500μmol photons m-2 s-1) and under natural fluctuating light (NatL) conditions. We performed a thorough characterization of the morphological, physiological, and biochemical properties focusing on photo-protective mechanisms. Our analyses corroborated the known properties of LL, NL, and HL plants. NatL plants, however, were found to combine characteristics of both LL and HL grown plants, leading to efficient and unique light utilization capacities. Strikingly, the high energy dissipation capacity of NatL plants correlated with increased dynamics of thylakoid membrane reorganization upon short-term acclimation to excess light. We conclude that the thylakoid membrane organization and particularly the light-dependent and reversible unstacking of grana membranes likely represent key factors that provide the basis for the high acclimation capacity of NatL grown plants to rapidly changing light intensities.

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