142 results on '"Janne Jänis"'
Search Results
2. Production and Characterization of Hydrothermal Extracts of the Needles from Four Conifer Tree Species: Scots Pine, Norway Spruce, Common Juniper, and European Larch
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Omolara O. Mofikoya, Eemeli Eronen, Marko Mäkinen, and Janne Jänis
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Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,Environmental Chemistry ,General Chemistry - Published
- 2023
3. Biochemical and Biophysical Characterization of Carbonic Anhydrase VI from Human Milk and Saliva
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Alma Yrjänäinen, Maarit S. Patrikainen, Latifeh Azizi, Martti E. E. Tolvanen, Mikko Laitaoja, Janne Jänis, Vesa P. Hytönen, Alessio Nocentini, Claudiu T. Supuran, Seppo Parkkila, Tampere University, BioMediTech, and Department of Clinical Chemistry
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Milk, Human ,Organic Chemistry ,Humans ,Bioengineering ,3111 Biomedicine ,Saliva ,Biochemistry ,Carbonic Anhydrases ,Fucose ,Analytical Chemistry - Abstract
Carbonic anhydrases (CA, EC 4.2.1.1) catalyze the hydration of carbon dioxide and take part in many essential physiological processes. In humans, 15 CAs are characterized, including the only secreted isoenzyme CA VI. CA VI has been linked to specific processes in the mouth, namely bitter taste perception, dental caries, and maintenance of enamel pellicle, and implicated in several immunity-related phenomena. However, little is known of the mechanisms of the above. In this study, we characterized human CA VI purified from saliva and milk with biophysical methods and measured their enzyme activities and acetazolamide inhibition. Size-exclusion chromatography showed peaks of salivary and milk CA VI corresponding to hexameric state or larger at pH 7.5. At pH 5.0 the hexamer peaks dominated. SDS- PAGE of milk CA VI protein treated with a bifunctional crosslinker further confirmed that a majority of CA VI is oligomers of similar sizes in solution. Mass spectrometry experiments confirmed that both of the two putative N-glycosylation sites, Asn67 and Asn256, are heterogeneously glycosylated. The attached glycans in milk CA VI were di- and triantennary complex-type glycans, carrying both a core fucose and 1 to 2 additional fucose units, whereas the glycans in salivary CA VI were smaller, seemingly degraded forms of core fucosylated complex- or hybrid-type glycans. Mass spectrometry also verified the predicted signal peptide cleavage site and the terminal residue, Gln 18, being in pyroglutamate form. Thorough characterization of CA VI paves way to better understanding of the biological function of the protein.
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- 2022
4. Healing Effects of Adipose-Derived Stromal Vascular Fraction on Busulfan-Induced Testicular Damage
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Rumeysa Emine Hekimoglu, Mukaddes Esrefoğlu, Fatma Bedia Karakaya Cimen, Birsen Elibol, Janne Jänis, and Ozge Pasin
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- 2023
5. Application of Reductive Amination by Heterologously Expressed Thermomicrobium Roseum L-Alanine Dehydrogenase to Synthesize L-Alanine Derivatives
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Huri Bulut, Jarkko Valjakka, Ossi Turunen, Berin Yilmazer, Ğarip Demir, Janne Jänis, and Barış Binay
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History ,Polymers and Plastics ,Bioengineering ,Business and International Management ,Applied Microbiology and Biotechnology ,Biochemistry ,Industrial and Manufacturing Engineering ,Biotechnology - Published
- 2023
6. Dissolved organic matter composition regulates microbial degradation and carbon dioxide production in pristine subarctic rivers
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Taija Saarela, Xudan Zhu, Helena Jäntti, Mizue Ohashi, Jun'ichiro Ide, Henri Siljanen, Aake Pesonen, Heidi Aaltonen, Anne Ojala, Hiroshi Nishimura, Timo Kekäläinen, Janne Jänis, Frank Berninger, and Jukka Pumpanen
- Abstract
Dissolved organic matter (DOM) degradation in freshwater rivers and streams plays a major role in the global carbon cycle. However, little is known about how the source and composition of riverine DOM contribute to the production of greenhouse gases, especially in high-latitude areas with a large proportion of carbon-rich peatlands. Here, we conducted for the first time the combination of molecular-level characterization of terrestrially derived DOM and the potential carbon dioxide (CO2) production measurements in pristine subarctic rivers of Finnish Lapland. 21-day incubation studies were conducted with water samples taken from two rivers differing in DOM content during spring and fall 2018. The changes in the DOM concentration and molecular composition, as well as the CO2 production, were measured. The DOM molecular characterization was carried out using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Our results demonstrate efficient mineralization of dissolved organic carbon (DOC) into CO2 in mineral soil associated clearwater river during the incubation, while significantly lower CO2 production per DOC was observed in the brown-water river surrounded by peatlands. The limited degradability in the brown-water river was caused by a large number of terrestrial and aromatic compounds (i.e., highly unsaturated and phenolic compounds, condensed aromatics, and polyphenolics) from surrounding peatlands. In the clearwater river, the percentage of formulas assigned to aliphatics decreased over the incubation, indicating microbial utilization of biolabile DOM. This study highlights the importance of energy-rich, biolabile molecular compounds and the contribution of clearwater systems in the DOM degradation dynamics of subarctic catchments.
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- 2022
7. Supplementary material to 'Dissolved organic matter composition regulates microbial degradation and carbon dioxide production in pristine subarctic rivers'
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Taija Saarela, Xudan Zhu, Helena Jäntti, Mizue Ohashi, Jun'ichiro Ide, Henri Siljanen, Aake Pesonen, Heidi Aaltonen, Anne Ojala, Hiroshi Nishimura, Timo Kekäläinen, Janne Jänis, Frank Berninger, and Jukka Pumpanen
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- 2022
8. Hybrid Inorganic-Organic Complexes of Zn, Cd, and Pb with a Cationic Phenanthro-diimine Ligand
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Diana Temerova, Tai-Che Chou, Kristina S. Kisel, Toni Eskelinen, Niko Kinnunen, Janne Jänis, Antti J. Karttunen, Pi-Tai Chou, Igor O. Koshevoy, University of Eastern Finland, National Taiwan University, Department of Chemistry and Materials Science, Aalto-yliopisto, and Aalto University
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Inorganic Chemistry ,Physical and Theoretical Chemistry - Abstract
Funding Information: Financial support from the Academy of Finland (decision 317903, I.O.K.; decision 340584, T.E. and A.J.K.; Flagship Programme, Photonics Research and Innovation PREIN, decision 320166) and computational resources from the Finnish IT Center for Science (CSC) are gratefully acknowledged. Publisher Copyright: © 2022 The Authors. Published by American Chemical Society. The phosphonium-decorated phenanthro-imidazolyl pyridine ligand, LP +Br, readily reacts with zinc(II) and cadmium(II) bromides to give inorganic-organic zero-dimensional compounds [ LP +ZnBr2]2[ZnBr4] ( 1 ) and [( LP +)2Cd2Br4][CdBr4] ( 2 ), respectively, upon crystallization. These salts are moderately fluorescent in the solid state under ambient conditions (λem = 458 nm, φem = 0.11 for 1 ; λem = 460 nm, φem = 0.13 for 2 ). Their emission results from spin-allowed electronic transitions localized on the organic component with the negligible effect of [MBr4]2- and MBr2 units. Contrary to ionic species 1 and 2 , lead(II) bromide affords a neutral and water-stable complex [( LP +)2Pb3Br8] ( 3 ), showing weak room-temperature phosphorescence arising from spin-orbit coupling due to the heavy atom effect. The emission, which is substantially enhanced for the amorphous sample of 3 (λem = 575 nm, φem = 0.06), is assigned to the intraligand triplet excited state, which is a rare phenomenon among Pb(II) molecular materials.
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- 2022
9. The way forward: Management and policy actions
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Lauri Hetemäki, Jyrki Kangas, Antti Asikainen, Janne Jänis, Jyri Seppälä, Ari Venäläinen, Heli Peltola, Hetemäki, Lauri, Kangas, Jyrki, Peltola, Heli, Faculty of Agriculture and Forestry, and Department of Forest Sciences
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4112 Forestry ,1172 Environmental sciences - Abstract
Along with the evidence and analyses expounded on in this book, this chapter provides conclusions and suggestions concerning policy implications. These are based on a perspective that calls attention to the need for a holistic approach to look at the nexus of forests, the bioeconomy and climate change. Moreover, it is emphasised that, given the different uses of forests and the scarcity of forest resources, it makes sense to try to find ways to maximise synergies and minimise trade-offs between the different usages of forests. The forest-based sector contributes to climate-change mitigation via three channels––forests are a carbon sink, forest-based products can substitute for fossil-based products, and these products can store carbon for up to centuries. However, achieving these mitigation potentials in the future depends on forests being made resilient to the changing climate. Therefore, mitigation and adapting forests to climate change are married, both needing to be advanced simultaneously. Globally and in the EU, around 80–90% of the CO2 emissions originate from the use of coal, oil and natural gas. Consequently, the core issue in the fight against climate change is the phasing out of fossil-based products. Reaching this goal will not be possible without substituting also forest-based bioproducts for the purposes we are using oil, coal and gas for today. In the EU, this implies paying more attention to the need to develop new innovations in the forest bioeconomy, improve the resource efficiency and circularity of the bioproducts already available, and monitor the environmental sustainability of the bioeconomy.
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- 2022
10. Primary structure determination and physicochemical characterization of DSP-3, a phosphatidylcholine binding glycoprotein of donkey seminal plasma
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Sk Alim, Mikko Laitaoja, Sonali S. Pawar, Thirumala Rao Talluri, Janne Jänis, and Musti J. Swamy
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Structural Biology ,General Medicine ,Molecular Biology ,Biochemistry - Published
- 2023
11. Crystal structure of the collagen prolyl 4-hydroxylase (C-P4H) catalytic domain complexed with PDI: Toward a model of the C-P4H α
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Abhinandan V, Murthy, Ramita, Sulu, Andrey, Lebedev, Antti M, Salo, Kati, Korhonen, Rajaram, Venkatesan, Hongmin, Tu, Ulrich, Bergmann, Janne, Jänis, Mikko, Laitaoja, Lloyd W, Ruddock, Johanna, Myllyharju, M Kristian, Koski, and Rik K, Wierenga
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Collagen prolyl 4-hydroxylases (C-P4H) are α
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- 2022
12. Valorization of Bark from Short Rotation Trees by Temperature-Programmed Slow Pyrolysis
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Antti Haapala, Qing Zhao, Janne Jänis, and Marko Mäkinen
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0106 biological sciences ,Acid value ,Chemistry ,020209 energy ,General Chemical Engineering ,Condensation ,Biomass ,Fraction (chemistry) ,02 engineering and technology ,General Chemistry ,15. Life on land ,Torrefaction ,01 natural sciences ,Article ,visual_art ,0202 electrical engineering, electronic engineering, information engineering ,visual_art.visual_art_medium ,Bark ,Water content ,Pyrolysis ,QD1-999 ,010606 plant biology & botany ,Nuclear chemistry - Abstract
The tree bark represents an abundant but currently underutilized forest biomass side stream. In this work, temperature-programmed slow pyrolysis with fractional condensation was used for thermochemical conversion of the bark obtained from three short rotation tree species, aspen, goat willow, and rowan. Heating was performed in three stages, drying (135 °C), torrefaction (275 °C), and pyrolysis (350 °C), and the resulting vapors were condensed at 120, 70, and 5 °C, producing nine liquid fractions. An additional fraction was collected in the pyrolysis stage at 0 °C. The obtained liquid fractions were characterized in terms of their yields and bulk chemistry (i.e., CHNOS content, water content, pH, and total acid number) as well as their molecular level chemistry by high-resolution mass spectrometry. The highest liquid yields were obtained for the fractions condensed at 70 °C. The water content varied considerably, being the highest for the drying fractions (>96%) and the lowest for the pyrolysis fractions obtained at 120 °C (0.1-2%). Considerable compositional differences were observed between the liquid fractions. While the drying fractions contained mostly some dissolved phenolics, the torrefaction fractions contained more sugaric compounds. In contrast, the pyrolysis fractions were enriched lipids (e.g., suberinic fatty acids and their derivatives) and alicyclic/aromatic hydrocarbons. These fractions could be further refined into different platforms and/or specialty chemicals. Thus, slow pyrolysis with fractional condensation offers a potential route for the valorization of tree bark residues from forest industry.
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- 2021
13. Valorization potential of the aqueous products from hydrothermal liquefaction and stepwise slow pyrolysis of wood bark and hemp hurds with yields and product comparison
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Noora Jokinen, Eemeli Eronen, Ayobami Salami, Marko Hyttinen, Janne Jänis, Jouko Vepsäläinen, Reijo Lappalainen, and Laura Tomppo
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Environmental Engineering ,Renewable Energy, Sustainability and the Environment ,Bioengineering ,Waste Management and Disposal - Published
- 2023
14. Pyroligneous Acids of Differently Pretreated Hybrid Aspen Biomass: Herbicide and Fungicide Performance
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Pasi Korkalo, Marleena Hagner, Janne Jänis, Marko Mäkinen, Janne Kaseva, Ulla Lassi, Kimmo Rasa, Tuula Jyske, Ecosystems and Environment Research Programme, Fifth Dimension - Vegetated roofs and walls in urban areas, and Urban Ecosystems
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EXTRACTION ,4112 Forestry ,biomass ,PYROLYSIS ,COMPONENTS ,fungi ,food and beverages ,General Chemistry ,11831 Plant biology ,OIL ,complex mixtures ,biopesticide ,CONVERSION ,torrefaction ,Chemistry ,ANTITERMITIC ACTIVITIES ,WOOD VINEGAR ,pyroligneous acid ,hybrid aspen ,ANTIFUNGAL ,herbicide ,fungicide ,cascade utilization ,QD1-999 ,BIRCH BARK - Abstract
The pyroligneous acids (PAs) of woody biomass produced by torrefaction have pesticidal properties. Thus, PAs are potential alternatives to synthetic plant protection chemicals. Although woody biomass is a renewable feedstock, its use must be efficient. The efficiency of biomass utilization can be improved by applying a cascading use principle. This study is novel because we evaluate for the first time the pesticidal potential of PAs derived from the bark of hybrid aspen (Populus tremula L. × Populus tremuloides Michx.) and examine simultaneously how the production of the PAs can be interlinked with the cascade processing of hybrid aspen biomass. Hybrid aspen bark contains valuable extractives that can be separated before the hemicellulose is thermochemically converted into plant protection chemicals. We developed a cascade processing scheme, where these extractives were first extracted from the bark with hot water (HWE) or with hot water and alkaline alcohol (HWE+AAE) prior to their conversion into PAs by torrefaction. The herbicidal performance of PAs was tested using Brassica rapa as the test species, and the fungicidal performance was proven using Fusarium culmorum. The pesticidal activities were compared to those of the PAs of debarked wood and of commercial pesticides. According to the results, extractives can be separated from the bark without overtly diminishing the weed and fungal growth inhibitor performance of the produced PAs. The HWE of the bark before its conversion into PAs appeared to have an enhancing effect on the herbicidal activity. In contrast, HWE+AAE lowered the growth inhibition performance of PAs against both the weeds and fungi. This study shows that hybrid aspen is a viable feedstock for the production of herbicidal and fungicidal active chemicals, and it is possible to utilize biomass according to the cascading use principle.
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- 2022
15. Calculation and Visualization of Binding Equilibria in Protein Studies
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Johan Pääkkönen, Janne Jänis, and Juha Rouvinen
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General Chemical Engineering ,General Chemistry - Abstract
A set of simulation applets has been developed for visualizing the behavior of the association and dissociation reactions in protein studies. These reactions are simple equilibrium reactions, and the equilibrium constants, most often dissociation constant
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- 2022
16. Supplementary material to 'Compositions of dissolved organic matter in the ice-covered waters above the Aurora hydrothermal vent system, Gakkel Ridge, Arctic Ocean'
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Muhammed Fatih Sert, Helge Niemann, Eoghan P. Reeves, Mats A. Granskog, Kevin P. Hand, Timo Kekäläinen, Janne Jänis, Pamela E. Rossel, Bénédicte Ferré, Anna Silyakova, and Friederike Gründger
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- 2022
17. Puy de Dôme Station (France): A Stoichiometric Approach to Compound Classification in Clouds
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Pascal Renard, Angelica Bianco, Janne Jänis, Timo Kekäläinen, Maxime Bridoux, Laurent Deguillaume, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), University of Eastern Finland, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Observatoire de Physique du Globe de Clermont-Ferrand (OPGC)
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Atmospheric Science ,APPI ,Geophysics ,biogenic sources ,Space and Planetary Science ,Earth and Planetary Sciences (miscellaneous) ,multidimensional stoichiometric constraint classification ,[SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology ,cloud water-soluble organic matter ,FT-ICR ,air mass history - Abstract
International audience; Seven cloud water samples were collected from May to October 2018 at the Puy de Dôme station (PUY) in France and analyzed by positive-ion atmospheric pressure photoionization [(+)APPI] Fourier transform ion cyclotron resonance mass spectrometry. The assigned formulas (ranging from 3,865 to 6,380) were attributed using the multidimensional stoichiometric constraint classification of Rivas-Ubach et al. (2018, https://doi.org.10.1021/acs.analchem.8b00529) to six main categories (RUCs): LipidC, ProteinC, Amino-sugarC, CarbohydrateC, NucleotideC, and OxyaromaticC. Back trajectories were calculated by the computing atmospheric trajectory tool (CAT) model to obtain information on the air mass history. Partial least square regressions were performed using chemical data, CAT back-trajectory calculations and FT-ICR MS data to analyze the environmental variability of the organic sample composition. ProteinC is correlated with the continental surface for air masses transported within the boundary layer, and Amino-sugarC is strongly correlated with acetate, NO3- and NH4+, suggesting Anthropogenic sources for amino sugars and proteins. LipidC is correlated with the sea surface for air masses transported within the free troposphere, confirming the long-range transport of marine biogenic sources. Concerning Oxy-aromaticC, given the correlations with oxidants and pollutants, as well as anti-correlations with local influence, we proposed a mechanism of oxidation from remote anthropogenic sources.
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- 2022
18. Outlook for the forest-based bioeconomy
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Elias Hurmekoski, Lauri Hetemäki, Janne Jänis, Hetemäki, Lauri, Kangas, Jyrki, Peltola, Heli, Department of Forest Sciences, Helsinki Institute of Sustainability Science (HELSUS), Forest Bioeconomy, Business and Sustainability, Forest Economics, Business and Society, and Faculty of Agriculture and Forestry
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4112 Forestry - Abstract
The state of the world’s managed forests is determined by the societal demands for wood resources and other ecosystem services. The forest-based sector is experiencing a number of structural changes, which makes the task of looking ahead important, but challenging. One of the main trends in the forest-based industries is diversification. On one hand, this refers to the emergence of new factors influencing the demand for forest-based products, which leads to substitution between forest-based products and alternative products. On the other hand, it refers to new market opportunities for forest-based industries in, for example, the construction, textiles, packaging, biochemicals and biofuels markets. As the importance of some of the traditional forest-based industries, such as communication papers, is declining, and new opportunities are simultaneously emerging, the sector will not necessarily be dominated by single sectors in the long term. However, research illuminating the possible impacts of the expected structural changes of the forest-based sector remains scarce. The uncertainties in the future outlook of the forest-based sector also imply great uncertainties in the demand for roundwood globally, and by extension, the extent of trade-offs between different ecosystem services and land uses.
- Published
- 2022
19. UVC-assisted photocatalytic degradation of carbamazepine by Nd-doped Sb2O3/TiO2 photocatalyst
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Janne Jänis, Mika Sillanpää, Zhao Wang, Shaobin Wang, Hongqi Sun, Senthil K. Thangaraj, and Varsha Srivastava
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Materials science ,Absorption spectroscopy ,Scanning electron microscope ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Catalysis ,Biomaterials ,chemistry.chemical_compound ,Crystallinity ,Colloid and Surface Chemistry ,chemistry ,Titanium dioxide ,Antimony trioxide ,Photocatalysis ,0210 nano-technology ,Photodegradation ,Nuclear chemistry - Abstract
The photocatalytic degradation of carbamazepine (CBZ) in ultra-pure water was investigated by using neodymium (Nd)-doped antimony trioxide (Sb2O3)/titanium dioxide (TiO2) photocatalyst under the UVC irradiations of 254 nm wavelength. The hydrothermal method was used for the fabrication catalyst samples with different ratios of Nd (0%–2%) dopant, and characterised by X-ray diffraction pattern (XRD) to investigate the crystallinity. Scanning electron microscopy (SEM) provided the surface morphologies, Bruanuer-Emmer-Teller (BET) analysis gave the textural properties, and UV–Vis diffuse reflectance absorption spectroscopy (DRS) was used for the investigation of the optical properties of synthesized catalysts. TEM images of Sb2O3 showed a nanorod-like structure while, in the Nd-doped Sb2O3/TiO2, a small dot-like structure was observed along with the nanorods. The surface area and band gap of 1% Nd-doped Sb2O3/TiO2 were found to be 9.56 m2 g−1 and 3.0 eV respectively. It was observed that the CBZ cannot be degraded in the absence of catalyst under UV light, while photocatalyst 1% Nd-doped Sb2O3/TiO2 at 0.5 g/L of catalyst dose showed the best photocatalytic activity towards CBZ degradation. The main degradation products were identified with high-resolution mass spectrometry. Moreover, the degradation of CBZ followed pseudo first-order kinetics and the rate constant was 0.017 min−1. Quenching tests by the addition of methanol from 100 to 500 mM were carried out to determine the major reactive oxygen species, which showed that OH radicals was involved in the CBZ degradation. Active species-trapping experiments revealed that ∙O2− is also responsible for the degradation of CBZ.
- Published
- 2020
20. Solvatochromic dual luminescence of Eu–Au dyads decorated with chromophore phosphines
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Janne Jänis, Andrey Belyaev, Igor Solovyev, Elena V. Grachova, Vladimir V. Sizov, Igor O. Koshevoy, and Sofia O. Slavova
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Lanthanide ,Anthracene ,010405 organic chemistry ,Solvatochromism ,Chromophore ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Fluorescence ,0104 chemical sciences ,3. Good health ,Inorganic Chemistry ,chemistry.chemical_compound ,Bipyridine ,chemistry ,Moiety ,Luminescence - Abstract
Phosphine ligands, containing chromophore substituents –π-spacer–NPh2 (π-spacer = biphenyl, L1; naphthalene-ethynylphenyl, L2; and ethynyl-(phenylethynyl)anthracene, L3), were used to generate the corresponding gold(I) alkynyl complexes Au1–Au3 (alkynyl = ethynylphenyl-2,2′-bipyridine, epbpy). These compounds demonstrate intense fluorescence, which originates from the bipolar donor–π-acceptor systems of coordinated phosphines with negligible contribution from the epbpy fragment. Due to the charge transfer characteristic of the excited state, Au1–Au3 reveal significant emission solvatochromism (particularly discernible for Au2, 428 nm in cyclohexane → 580 nm in acetonitrile). The bipyridine moiety of Au1–Au3 was utilized for binding these metalloligands to the {Eu(tta)3} red emitter (tta = 3-thenoyltrifluoroacetonate) to give a family of novel dyads Au1Eu–Au3Eu. Incomplete energy transfer from L1–L3 to lanthanide ions, which are primarily sensitized by diketonate ligands, leads to dual luminescence. Analogous to the parent complexes Au1–Au3, the fluorescence component of the dyads is highly sensitive to the solvent polarity that provides great opportunities for color tuning, including white light generation.
- Published
- 2020
21. Quantitation of Thyroid Hormone Binding to Anti-Thyroxine Antibody Fab Fragment by Native Mass Spectrometry
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Janne Jänis, Senthil K. Thangaraj, Henri O. Arola, Juha Rouvinen, Antti Tullila, and Tarja K. Nevanen
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General Chemical Engineering ,chemistry.chemical_element ,Iodine ,01 natural sciences ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,medicine ,Thyroid hormone binding ,QD1-999 ,030304 developmental biology ,0303 health sciences ,biology ,010401 analytical chemistry ,Thyroid ,General Chemistry ,Ligand (biochemistry) ,Affinities ,0104 chemical sciences ,Chemistry ,medicine.anatomical_structure ,chemistry ,Biochemistry ,Thyronine ,biology.protein ,Antibody ,Hormone - Abstract
Thyroid hormones are important regulatory hormones, acting on nearly every cell in the body. The two main thyroid hormones are l-thyroxine (tetraiodo-l-thyronine, T4) and 3,3′,5-triiodo-l-thyronine (T3), which are produced in the thyroid gland and secreted into the blood stream. Other important thyroid hormone metabolites are 3,3′-diiodo-l-thyronine (T2) and l-thyronine (T0), which may show increased levels in circulation due to dietary iodine deficiency or other medical disorders. Owing to their central role in cellular functions, sensitive and specific detection methods for thyroid hormones are needed. In this work, native mass spectrometry (MS) was used to quantitate thyroid hormone binding to the anti-T4 antibody Fab fragment. First, the binding affinity for T2 was determined via direct ligand titration experiments. Then, the affinities for the other ligands were determined by competition experiments using T2 as the "low-affinity" reference ligand. The highest affinity was measured for T3, followed by T4, T2, and T0 (Kd = 29, 3.4, and 260 nM and 130 μM, respectively). Thus, it is evident that the number and positions of the iodine substituents within the thyronine rings are important for the ligand binding affinity of anti-T4 Fab. Surprisingly, structurally related tetrahalogen bisphenols were also able to bind to anti-T4 Fab with nanomolar affinities.
- Published
- 2019
22. Mechanistic insight into efficient removal of tetracycline from water by Fe/graphene
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Anna Lähde, Sara-Maaria Alatalo, Daniel C.W. Tsang, Amit Bhatnagar, Senthil K. Thangaraj, Arūnas Meščeriakovas, Janne Jänis, Niko M. Kinnunen, and Ehsan Daneshvar
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Zerovalent iron ,Materials science ,Annealing (metallurgy) ,Graphene ,General Chemical Engineering ,Composite number ,Portable water purification ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,6. Clean water ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,law.invention ,Adsorption ,Chemical engineering ,law ,Environmental Chemistry ,Sewage treatment ,Water treatment ,0210 nano-technology - Abstract
The release of pharmaceuticals into aquatic environments is a serious concern due to the persistence and potential health and environmental risks of these substances. Surface and ground waters are polluted with a variety of pharmaceuticals due to insufficient water purification processes in wastewater treatment plants. Here, we report a simple procedure for the production of composite materials consisting of zero-valent iron embedded in few-layer graphene, Fe/graphene, through induction annealing at 900 °C. Zero-valent iron was observed as magnetic 1 µm-sized crystals embedded in the graphene matrix appearing in the α- and γ-forms. This Fe/graphene composite was applied as an adsorbent for the removal of tetracycline (a pharmaceutical) from water. The Fe/graphene showed high tetracycline removal efficiency (422 mg/g) under optimized conditions. Furthermore, the Fe/graphene possessed self-regenerating features prolonging its lifetime and total removal capacity up to 660 mg/g, thus making it a potential material for removing tetracycline from water.
- Published
- 2019
23. Carbon Budget and Molecular Structure of Natural Organic Matter in Bank Infiltrated Groundwater
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Janne Jänis, Hanne Laine-Kaulio, Harri Koivusalo, Maija Jylhä-Ollila, Timo Kekäläinen, Jos Schilder, Paula Niinikoski-Fuβwinkel, Department of Built Environment, University of Jyväskylä, RWTH Aachen University, University of Eastern Finland, Aalto-yliopisto, and Aalto University
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liuennut orgaaninen hiili ,massaspektrometria ,Water table ,0208 environmental biotechnology ,chemistry.chemical_element ,Aquifer ,Fresh Water ,tekopohjavesi ,02 engineering and technology ,järvet ,Vadose zone ,ddc:550 ,Organic matter ,Computers in Earth Sciences ,Groundwater ,Water Science and Technology ,Total organic carbon ,chemistry.chemical_classification ,managed aquifer recharge ,geography ,pohjavesi ,vedenpuhdistus ,geography.geographical_feature_category ,Molecular Structure ,Groundwater recharge ,dissolved organic matter ,pohjavesialueet ,Carbon ,020801 environmental engineering ,lake-groundwater interaction ,molecular composition ,pintavesi ,chemistry ,Environmental chemistry ,Environmental science ,orgaaninen aines ,Seasons ,Water Pollutants, Chemical - Abstract
Groundwater : : journal of the Association of Ground-Water Scientists and Engineers, a division of the National Ground Water Association (2021). doi:10.1111/gwat.13087, Published by Wiley-Blackwell, Oxford [u.a.]
- Published
- 2021
24. Chemical fingerprinting of phenolic compounds in Finnish berry wines using Fourier transform ion cyclotron resonance mass spectrometry
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Yanning, Dou, Menglan, Mei, Timo, Kettunen, Marko, Mäkinen, and Janne, Jänis
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Fourier Analysis ,Phenols ,Fruit ,Wine ,General Medicine ,Cyclotrons ,Finland ,Gas Chromatography-Mass Spectrometry ,Mass Spectrometry ,Food Science ,Analytical Chemistry - Abstract
Chemical fingerprinting of phenolic compounds present in Finnish berry wines was performed using a direct-infusion Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The main aim of this study was to compare the phenolics profiles of wines produced from natural and/or cultivated berries and to demonstrate the feasibility of FT-ICR MS for a direct chemical analysis of the wine samples without chromatographic separation. First, phenolic compounds were recovered from the wine samples by solid-phase extraction (SPE), and the total phenolic content (TPC) was then determined by a Folin-Ciocalteau assay. The TPC of the original berry wines varied from 421 to 2108 mg/L, while the TPC of the extracts was 157-1525 mg/L. Over fifty phenolic compounds were tentatively identified from the wine samples by FT-ICR MS, whose concentrations highly varied depending on the types of berries used in the winemaking process.
- Published
- 2022
25. Purification, molecular characterization and ligand binding properties of the major donkey seminal plasma protein DSP-1
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Sk Alim, Musti J. Swamy, Janne Jänis, Sudheer K. Cheppali, Thirumala Rao Talluri, and Mikko Laitaoja
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Models, Molecular ,Glycan ,Circular dichroism ,Chemical Phenomena ,Seminal Plasma Proteins ,Protein Conformation ,Ligands ,Biochemistry ,Chromatography, Affinity ,Mass Spectrometry ,Cell membrane ,stomatognathic system ,Structural Biology ,medicine ,Animals ,Molecular Biology ,Peptide sequence ,Sperm plasma membrane ,biology ,Phosphorylcholine ,Chemistry ,Spectrum Analysis ,General Medicine ,Equidae ,Blood proteins ,medicine.anatomical_structure ,biology.protein ,Protein Binding - Abstract
Fibronectin type-II (FnII) family proteins are the major proteins in many mammalian species including bull, horse and pig. In the present study, a major FnII protein has been identified and isolated from donkey (Equus hemionus) seminal plasma, which we refer to as D onkey S eminal P lasma protein-1 (DSP-1). The amino acid sequence determined by mass spectrometry and computational modeling studies revealed that DSP-1 is homologous to other mammalian seminal plasma proteins, including bovine PDC-109 (also known as BSP-A1/A2) and equine HSP-1/2. High-resolution LC-MS analysis indicated that the protein is heterogeneously glycosylated and also contains multiple acetylations, occurring in the attached glycans. Structural and thermal stability studies on DSP-1 employing CD spectroscopy and differential scanning calorimetry showed that the protein unfolds at ~43 °C and binding to phosphorylcholine (PrC) – the head group moiety of choline phospholipids – increases its thermal stability. Intrinsic fluorescence titrations revealed that DSP-1 recognizes lyso-phosphatidylcholine with over 100-fold higher affinity than PrC. Further, interaction of DSP-1 with erythrocytes, a model cell membrane, revealed that DSP-1 binding is mediated by a specific interaction with choline phospholipids and results in membrane perturbation, suggesting that binding of this protein to sperm plasma membrane could be physiologically significant.
- Published
- 2021
26. Structural insights into the substrate-binding proteins Mce1A and Mce4A from
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Pooja, Asthana, Dhirendra, Singh, Jan Skov, Pedersen, Mikko J, Hynönen, Ramita, Sulu, Abhinandan V, Murthy, Mikko, Laitaoja, Janne, Jänis, Lee W, Riley, and Rajaram, Venkatesan
- Subjects
substrate-binding proteins ,lipids ,crystal structure ,ABC transporters ,Mce4 ,membrane proteins ,Mycobacterium tuberculosis ,SAXS ,protein structure ,Research Papers ,mammalian cell entry proteins ,Mce1 ,X-ray crystallography - Abstract
The mammalian cell entry genes (mceA–mceF) encode the substrate-binding proteins of the lipid-transporting Mce complexes in mycobacteria. The MCE domain of Mce4A has been crystallized as a domain-swapped dimer with the signature β-barrel fold. Solution studies show that the domains of Mce1A and Mce4A are predominantly monomeric and suggest that the helical domain is involved in lipid interactions., Mycobacterium tuberculosis (Mtb), which is responsible for more than a million deaths annually, uses lipids as the source of carbon and energy for its survival in the latent phase of infection. Mtb cannot synthesize all of the lipid molecules required for its growth and pathogenicity. Therefore, it relies on transporters such as the mammalian cell entry (Mce) complexes to import lipids from the host across the cell wall. Despite their importance for the survival and pathogenicity of Mtb, information on the structural properties of these proteins is not yet available. Each of the four Mce complexes in Mtb (Mce1–4) comprises six substrate-binding proteins (SBPs; MceA–F), each of which contains four conserved domains (N-terminal transmembrane, MCE, helical and C-terminal unstructured tail domains). Here, the properties of the various domains of Mtb Mce1A and Mce4A, which are involved in the import of mycolic/fatty acids and cholesterol, respectively, are reported. In the crystal structure of the MCE domain of Mce4A (MtMce4A39–140) a domain-swapped conformation is observed, whereas solution studies, including small-angle X-ray scattering (SAXS), indicate that all Mce1A and Mce4A domains are predominantly monomeric. Further, structural comparisons show interesting differences from the bacterial homologs MlaD, PqiB and LetB, which form homohexamers when assembled as functional transporter complexes. These data, and the fact that there are six SBPs in each Mtb mce operon, suggest that the MceA–F SBPs from Mce1–4 may form heterohexamers. Also, interestingly, the purification and SAXS analysis showed that the helical domains interact with the detergent micelle, suggesting that when assembled the helical domains of MceA–F may form a hydrophobic pore for lipid transport, as observed in EcPqiB. Overall, these data highlight the unique structural properties of the Mtb Mce SBPs.
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- 2021
27. A Comparative Study of Pyrolysis Liquids by Slow Pyrolysis of Industrial Hemp Leaves, Hurds and Roots
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Ayobami Salami, Jorma Heikkinen, Laura Tomppo, Marko Hyttinen, Timo Kekäläinen, Janne Jänis, Jouko Vepsäläinen, and Reijo Lappalainen
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chemical characterization ,Proton Magnetic Resonance Spectroscopy ,economic assessment ,Organic chemistry ,APPI FT-ICR MS ,slow pyrolysis ,Plant Roots ,Gas Chromatography-Mass Spectrometry ,Mass Spectrometry ,Article ,NMR ,Plant Leaves ,industrial hemp ,QD241-441 ,nonvolatile compounds ,Spectroscopy, Fourier Transform Infrared ,volatile compounds ,pyrolysis liquid ,GC-MS ,Pyrolysis ,Cannabis - Abstract
This study assessed the pyrolysis liquids obtained by slow pyrolysis of industrial hemp leaves, hurds, and roots. The liquids recovered between a pyrolysis temperature of 275–350 °C, at two condensation temperatures 130 °C and 70 °C, were analyzed. Aqueous and bio-oil pyrolysis liquids were produced and analyzed by proton nuclear magnetic resonance (NMR), gas chromatography–mass spectrometry (GC-MS), and atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry (APPI FT-ICR MS). NMR revealed quantitative concentrations of the most abundant compounds in the aqueous fractions and compound groups in the oily fractions. In the aqueous fractions, the concentration range of acetic acid was 50–241 gL−1, methanol 2–30 gL−1, propanoic acid 5–20 gL−1, and 1-hydroxybutan-2-one 2 gL−1. GC-MS was used to compare the compositions of the volatile compounds and APPI FT-ICR MS was utilized to determine the most abundant higher molecular weight compounds. The different obtained pyrolysis liquids (aqueous and oily) had various volatile and nonvolatile compounds such as acetic acid, 2,6-dimethoxyphenol, 2-methoxyphenol, and cannabidiol. This study provides a detailed understanding of the chemical composition of pyrolysis liquids from different parts of the industrial hemp plant and assesses their possible economic potential.
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- 2021
28. Gingerbread ingredient-derived carbons-assembled CNT foam for the efficient peroxymonosulfate-mediated degradation of emerging pharmaceutical contaminants
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Mika Sillanpää, Senthil K. Thangaraj, Janne Jänis, Mohamed Chaker Ncibi, Tam Do Minh, and Varsha Srivastava
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Spin trapping ,Singlet oxygen ,Process Chemistry and Technology ,Radical ,Catalysis ,Fourier transform ion cyclotron resonance ,Solvent ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Phenol ,Pyrolysis ,General Environmental Science - Abstract
This article reports on the macronization of self-supported 3D CNT foam inter-connected by heteroatom-enriched porous shells derived from renewable baking ingredients via mild pyrolysis. The synthesized hybrids enabled disintegrating peroxymonosulfate (PMS) into reactive oxidants (sulfate radicals, hydroxyl radicals, and singlet oxygen) for the degradation of atenolol, iopamidol, metformin, trimethoprim, and phenol in water. Hierarchically structured nitrogen- and oxygen-doping significantly enhanced adsorptive and catalytic performance whereas the magnetic 3D framework promoted mass transport, multicycle use and induced synergetic effects via the Me-Nx-C interfaces. The samples were highly efficient for degradative removal of model pollutants at low catalyst and PMS dose. The catalyst loading, PMS dose, contact time, and temperature positively influenced the removal potency while pH and water matrix governed the rates differently. Spin trapping, oxidant quenching and solvent isotope effect study coupled with liquid chromatography and Fourier transform ion cyclotron resonance mass spectrometry analysis suggested the footprints of transformation products via a dual-mode (radical and non-radical) activation of PMS. This durable, magnetic carbofoam might be a promising catalyst for the oxidative abatement of pharmaceutical micropollutants from contaminated waters.
- Published
- 2019
29. The peroxisomal zebrafish SCP2-thiolase (type-1) is a weak transient dimer as revealed by crystal structures and native mass spectrometry
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Tiila-Riikka Kiema, Chandan J. Thapa, Mikko Laitaoja, Werner Schmitz, Mirko M. Maksimainen, Toshiyuki Fukao, Juha Rouvinen, Janne Jänis, and Rik K. Wierenga
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Models, Molecular ,0303 health sciences ,Cell Biology ,Zebrafish Proteins ,Biochemistry ,Substrate Specificity ,03 medical and health sciences ,0302 clinical medicine ,Catalytic Domain ,Animals ,Humans ,Acyl Coenzyme A ,Carrier Proteins ,Molecular Biology ,Zebrafish ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
The SCP2 (sterol carrier protein 2)-thiolase (type-1) functions in the vertebrate peroxisomal, bile acid synthesis pathway, converting 24-keto-THC-CoA and CoA into choloyl-CoA and propionyl-CoA. This conversion concerns the β-oxidation chain shortening of the steroid fatty acyl-moiety of 24-keto-THC-CoA. This class of dimeric thiolases has previously been poorly characterized. High-resolution crystal structures of the zebrafish SCP2-thiolase (type-1) now reveal an open catalytic site, shaped by residues of both subunits. The structure of its non-dimerized monomeric form has also been captured in the obtained crystals. Four loops at the dimer interface adopt very different conformations in the monomeric form. These loops also shape the active site and their structural changes explain why a competent active site is not present in the monomeric form. Native mass spectrometry studies confirm that the zebrafish SCP2-thiolase (type-1) as well as its human homolog are weak transient dimers in solution. The crystallographic binding studies reveal the mode of binding of CoA and octanoyl-CoA in the active site, highlighting the conserved geometry of the nucleophilic cysteine, the catalytic acid/base cysteine and the two oxyanion holes. The dimer interface of SCP2-thiolase (type-1) is equally extensive as in other thiolase dimers; however, it is more polar than any of the corresponding interfaces, which correlates with the notion that the enzyme forms a weak transient dimer. The structure comparison of the monomeric and dimeric forms suggests functional relevance of this property. These comparisons provide also insights into the structural rearrangements that occur when the folded inactive monomers assemble into the mature dimer.
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- 2019
30. Diversification of the forest industries: role of new wood-based products
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Lauri Hetemäki, Janne Jänis, Marko Mäkinen, Ragnar Jonsson, Jaana Korhonen, Elias Hurmekoski, and Pekka Leskinen
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Global and Planetary Change ,Ecology ,Natural resource economics ,020209 energy ,Forestry ,02 engineering and technology ,010501 environmental sciences ,Diversification (marketing strategy) ,01 natural sciences ,Biofuel ,0202 electrical engineering, electronic engineering, information engineering ,Business ,Forest industry ,Value chain ,Life-cycle assessment ,0105 earth and related environmental sciences - Abstract
This study identifies new wood-based products with considerable potential and attractive markets, including textiles, liquid biofuels, platform chemicals, plastics, and packaging. We apply a mixed-...
- Published
- 2018
31. Structural insights into the substrate-binding proteins Mce1A and Mce4A from Mycobacterium tuberculosis
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Pooja Asthana, Dhirendra Singh, Jan Skov Pedersen, Mikko J. Hynönen, Ramita Sulu, Abhinandan V. Murthy, Mikko Laitaoja, Janne Jänis, Lee W. Riley, Rajaram Venkatesan
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- 2021
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32. Structural insights on the substrate-binding proteins of the Mycobacterium tuberculosis mammalian-cell-entry (Mce) 1 and 4 complexes
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Asthana P, Rajaram Venkatesan, Singh D, Mikko J. Hynönen, Jakob Skou Pedersen, Mikko Laitaoja, R. Sulu, Lee W. Riley, Janne Jänis, and A.V. Murthy
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chemistry.chemical_classification ,0303 health sciences ,biology ,030306 microbiology ,Chemistry ,Periplasmic space ,biology.organism_classification ,DNA-binding protein ,Transmembrane protein ,3. Good health ,Mycolic acid ,Mycobacterium tuberculosis ,Cell wall ,Hydrophobic effect ,03 medical and health sciences ,Biophysics ,Lipid bilayer ,030304 developmental biology - Abstract
Tuberculosis (Tb), caused by Mycobacterium tuberculosis (Mtb), is responsible for more than a million deaths annually. In the latent phase of infection, Mtb uses lipids as the source of carbon and energy for its survival. The lipid molecules are transported across the cell wall via multiple transport systems. One such set of widely present and less-studied transporters is the Mammalian-cell-entry (Mce) complexes. Here, we report the properties of the substrate-binding proteins (SBPs; MceA-F) of the Mce1 and Mce4 complexes from Mtb which are responsible for the import of mycolic acid/fatty acids, and cholesterol respectively. MceA-F are composed of four domains namely, transmembrane, MCE, helical and tail domains. Our studies show that MceA-F are predominantly monomeric when purified individually and do not form homohexamers unlike the reported homologs (MlaD, PqiB and LetB) from other prokaryotes. The crystal structure of MCE domain of Mtb Mce4A (MtMce4A39-140) determined at 2.9 Å shows the formation of an unexpected domain-swapped dimer in the crystals. Further, the purification and small-angle X-ray scattering (SAXS) analysis on MtMce1A, MtMce4A and their domains suggest that the helical domain requires hydrophobic interactions with the detergent molecules for its stability. Combining all the experimental data, we propose a heterohexameric arrangement of MtMceA-F SBPs, where the soluble MCE domain of the SBPs would remain in the periplasm with the helical domain extending to the lipid layer forming a hollow channel for the transport of lipids across the membranes. The tail domain would reach the cell surface assisting in lipid recognition and binding.
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- 2020
33. Paclitaxel, Imatinib and 5-Fluorouracil Increase the Unbound Fraction of Flucloxacillin In Vitro
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Maximilian Stolte, Weaam Ali, André Gessner, Nahed El-Najjar, and Janne Jänis
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0301 basic medicine ,Microbiology (medical) ,drug-drug interactions ,030106 microbiology ,610 Medizin ,Pharmacology ,Biochemistry ,Microbiology ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Intensive care ,medicine ,polycyclic compounds ,α-1-acid glycoprotein ,cancer ,Pharmacology (medical) ,General Pharmacology, Toxicology and Pharmaceutics ,albumin ,ddc:610 ,anti-infective agents ,ultrafiltration ,lcsh:RM1-950 ,Albumin ,virus diseases ,Human serum albumin ,Blood proteins ,respiratory tract diseases ,Penicillin ,lcsh:Therapeutics. Pharmacology ,Infectious Diseases ,Paclitaxel ,chemistry ,030220 oncology & carcinogenesis ,Flucloxacillin ,Drug carrier ,medicine.drug - Abstract
Flucloxacillin (FLU), an isoxazolyl penicillin, is widely used for the treatment of different bacterial infections in intensive care units (ICU). Being highly bound to plasma proteins, FLU is prone to drug-drug interactions (DDI) when administered concurrently with other drugs. As FLU is binding to both Sudlow&rsquo, s site I and site II of human serum albumin (HSA), competitive and allosteric interactions with other drugs, highly bound to the same sites, seem conceivable. Knowledge about interaction(s) of FLU with the widely used anticancer agents paclitaxel (PAC), imatinib (IMA), and 5-fluorouracil (5-FU is scarce. The effects of the selected anticancer agents on the unbound fraction of FLU were evaluated in pooled plasma as well as in HSA and &alpha, 1-acid glycoprotein (AGP) samples, the second major drug carrier in plasma. FLU levels in spiked samples were analyzed by LC-MS/MS after ultrafiltration. Significant increase in FLU unbound fraction was observed when in combination with PAC and IMA and to a lesser extent with 5-FU. Furthermore, significant binding of FLU to AGP was observed. Collectively, this is the first study showing the binding of FLU to AGP as well as demonstrating a significant DDI between PAC/IMA/5-FU and FLU.
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- 2020
34. Oxidation of 2,4-dichlorophenol in saline water by unactivated peroxymonosulfate: Mechanism, kinetics and implication for in situ chemical oxidation
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Janne Jänis, Senthil K. Thangaraj, Mika Sillanpää, Eveliina Repo, Yuri Park, Xu Zhao, Huabin Zeng, and Feiping Zhao
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Environmental Engineering ,010504 meteorology & atmospheric sciences ,Hypochlorous acid ,Kinetics ,Inorganic chemistry ,2,4-Dichlorophenol ,010501 environmental sciences ,Saline water ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,chemistry ,In situ chemical oxidation ,Peroxydisulfate ,Environmental Chemistry ,Degradation (geology) ,Reactivity (chemistry) ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Inorganic and organic pollutants present a hazard to surface and groundwater resources. Peroxymonosulfate (PMS, HSO5−) has received increasing attention for in situ chemical oxidation (ISCO) capable of remediating contaminated sites. Considering that saline waters occur widely in natural environments, it is desirable to evaluate the effect of Cl− on the PMS oxidation of organic compounds. In this study, 2,4-dichlorophenol (2,4-DCP) was used as a model pollutant. At a PMS concentration of 2.0 mM, Cl− concentration of 50 mM, and solution pH of 7.0, 2,4-DCP was completely degraded by PMS in the presence of Cl− (PMS/Cl− system), while PMS alone exhibited almost no reactivity with 2,4-DCP. The degradation of 2,4-DCP was optimized at a solution pH of 8.4 and high concentrations of PMS and Cl−. Quenching experiments and degradation pathway analyses indicated that HClO was responsible for 2,4-DCP oxidation, and HClO was mainly generated by the interaction of Cl− with HSO5−, rather than SO52−. Consequently, the transformation from HSO5− to HClO appeared under a solution pH of 10.0 and was favored in an acidic solution. Given the ambient pH and Cl− concentrations of saline waters, a considerable amount of HClO may be produced by the interaction of PMS with Cl− in the oxidant delivery stage of ISCO processes. Interestingly, H2O2 and peroxydisulfate did not exhibit reactions similar to those of PMS. This research indicated that caution must be exercised when choosing an oxidant for ISCO processes in saline waters.
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- 2020
35. The F1 loop of the talin head domain acts as a gatekeeper in integrin activation and clustering
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R. Holland Cheng, Magdaléna von Essen, Vesa P. Hytönen, Janne Jänis, Adam Orłowski, Juha A. E. Määttä, Rolle Rahikainen, Mikko Laitaoja, Marie-Claude Jacquier, Anne T. Tuukkanen, Bernhard Wehrle-Haller, Xiaonan Liu, Tomasz Róg, Jinhua Wu, Sampo Kukkurainen, Dmitri I. Svergun, Pingfeng Zhang, Markku Varjosalo, Latifeh Azizi, Ilpo Vattulainen, Mo Baikoghli, Tampere University, BioMediTech, Department of Clinical Chemistry, Physics, Institute of Biotechnology, Molecular Systems Biology, Biosciences, and Department of Physics
- Subjects
Talin ,MONOCLONAL-ANTIBODY ,Integrin ,environment and public health ,0302 clinical medicine ,β3 integrin ,Cluster Analysis ,0303 health sciences ,SITES ,FERM domain ,biology ,Integrin beta3 ,3. Good health ,Cell biology ,Talin/genetics/metabolism ,embryonic structures ,biological phenomena, cell phenomena, and immunity ,CELL-ADHESION ,Integrin beta3/metabolism ,Protein Binding ,STRUCTURAL BASIS ,Protein Structure ,animal structures ,Activation ,macromolecular substances ,Molecular dynamics ,SEQUENCE ,Clustering ,03 medical and health sciences ,ddc:570 ,Cell Adhesion ,Inner membrane ,Cell adhesion ,Cluster analysis ,ddc:612 ,030304 developmental biology ,BINDING-LIKE DOMAIN ,Cell Biology ,AUTOINHIBITION ,KINDLIN-3 ,X-RAY-SCATTERING ,Protein Structure, Tertiary ,Cytoplasm ,biology.protein ,1182 Biochemistry, cell and molecular biology ,3111 Biomedicine ,030217 neurology & neurosurgery ,Tertiary ,Cysteine ,FERM DOMAIN - Abstract
Journal of cell science 133(19), jcs239202 (1-15) - (2020). doi:10.1242/jcs.239202, Integrin activation and clustering by talin are early steps of cell adhesion. Membrane-bound talin head domain and kindlin bind to the �� integrin cytoplasmic tail, cooperating to activate the heterodimeric integrin, and the talin head domain induces integrin clustering in the presence of Mn$^{2+}$. Here we show that kindlin-1 can replace Mn2+ to mediate ��3 integrin clustering induced by the talin head, but not that induced by the F2���F3 fragment of talin. Integrin clustering mediated by kindlin-1 and the talin head was lost upon deletion of the flexible loop within the talin head F1 subdomain. Further mutagenesis identified hydrophobic and acidic motifs in the F1 loop responsible for ��3 integrin clustering. Modeling, computational and cysteine crosslinking studies showed direct and catalytic interactions of the acidic F1 loop motif with the juxtamembrane domains of ��- and ��3-integrins, in order to activate the ��3 integrin heterodimer, further detailing the mechanism by which the talin���kindlin complex activates and clusters integrins. Moreover, the F1 loop interaction with the ��3 integrin tail required the newly identified compact FERM fold of the talin head, which positions the F1 loop next to the inner membrane clasp of the talin-bound integrin heterodimer., Published by Company of Biologists Limited, Cambridge
- Published
- 2020
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- View/download PDF
36. In-Depth Analysis of Raw Bio-Oil and Its Hydrodeoxygenated Products for a Comprehensive Catalyst Performance Evaluation
- Author
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Ogechukwu Okafor, Janne Jänis, Idoia Hita, Timo Kekäläinen, Tomás Cordero, Pedro Castaño, José Rodríguez-Mirasol, Tomás Cordero-Lanzac, and Javier Bilbao
- Subjects
Renewable Energy, Sustainability and the Environment ,Chemistry ,General Chemical Engineering ,Biomass ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Pulp and paper industry ,01 natural sciences ,0104 chemical sciences ,Catalysis ,Environmental Chemistry ,Composition (visual arts) ,0210 nano-technology ,Hydrodeoxygenation ,Pyrolysis ,Oxygenate - Abstract
Biomass pyrolysis liquids (bio-oils) unavoidably require catalytic hydrodeoxygenation (HDO) for their upgrading and stabilization for commercial usage. The complex composition of bio-oil constrains...
- Published
- 2020
- Full Text
- View/download PDF
37. Heterometallic Cluster-Capped Tetrahedral Assemblies with Postsynthetic Modification of the Metal Cores
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Elena V. Grachova, Julia R. Shakirova, Igor O. Koshevoy, Antti J. Karttunen, Senthil K. Thangaraj, Vladislav V. Gurzhiy, Janne Jänis, Alexey S. Melnikov, and Sergey P. Tunik
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Materials science ,Supramolecular chemistry ,Coinage metals ,010402 general chemistry ,01 natural sciences ,Catalysis ,chemistry.chemical_compound ,Isostructural ,ta216 ,ta116 ,010405 organic chemistry ,alkyne ligands ,General Chemistry ,General Medicine ,Metallacycle ,coinage metals ,0104 chemical sciences ,phosphorescence ,Crystallography ,Triphosphane ,chemistry ,Excited state ,cluster compounds ,heterometallic complexes ,Luminescence ,Phosphorescence - Abstract
Combining the star-shaped alkynyl ligands with low-nuclearity gold-copper triphosphane clusters produces 3D metallocage aggregates, which demonstrate room temperature phosphorescence in solution (max Φem =0.6). Their luminescence mainly originates from cluster-localized metal-to-ligand charge transfer excited state. These supramolecular assemblies can be easily converted into the isostructural gold-silver congeners by the direct exchange of the metal ions. Such modification of the terminal metal cores switches the emission to the intraligand (alkyne) electronic transitions of the triplet manifold, that represents an unusual optical functionality among the metallocycle/metallocage complexes.
- Published
- 2018
38. Synthesis of Novel Anti-inflammatory Psoralen Derivatives - Structures with Distinct Anti-Inflammatory Activities
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Pirjo Vainiotalo, Katriina Vuolteenaho, Juri M. Timonen, Janne Jänis, Paula Aulaskari, Eeva Moilanen, Riina Nieminen, and Tiina Leppänen
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0301 basic medicine ,medicine.drug_class ,Organic Chemistry ,Pharmacology ,01 natural sciences ,Anti-inflammatory ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,medicine ,Psoralen - Published
- 2018
39. Development of hypoallergenic variants of the major horse allergen Equ c 1 for immunotherapy by rational structure based engineering
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Juha Rouvinen, Janne Jänis, Jaana Haka, Merja Niemi, Kristiina Takkinen, and Pekka Mattila
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Models, Molecular ,0301 basic medicine ,Antigen processing and presentation ,medicine.medical_treatment ,Molecular Conformation ,lcsh:Medicine ,Signal transduction ,medicine.disease_cause ,Histamine Release ,Mass Spectrometry ,law.invention ,chemistry.chemical_compound ,Applied immunology ,0302 clinical medicine ,Allergen ,law ,lcsh:Science ,Desensitization (medicine) ,Vaccines ,Multidisciplinary ,biology ,Chemistry ,Immunochemistry ,Antigenic Variation ,Lipocalins ,Allergic response ,Recombinant DNA ,Antibody ,Histamine ,Protein vaccines ,Article ,Structure-Activity Relationship ,03 medical and health sciences ,Hypersensitivity ,medicine ,Animals ,Humans ,Horses ,lcsh:R ,Wild type ,Genetic Variation ,Hypoallergenic ,Allergens ,Immunoglobulin E ,Molecular biology ,030104 developmental biology ,030228 respiratory system ,Desensitization, Immunologic ,biology.protein ,lcsh:Q ,Protein design - Abstract
The use of recombinant allergens is a promising approach in allergen-specific immunotherapy (AIT). Considerable limitation, however, has been the ability of recombinant allergens to activate effector cells leading to allergic reactions. Recombinant hypoallergens with preserved protein folding and capacity to induce protective IgG antibodies binding effectively to the native allergen upon sensitization would be beneficial for safer AIT. In this study, hypoallergen variants of the major horse allergen Equ c 1 were designed by introducing one point mutation on the putative IgE epitope region and two mutations on the monomer-monomer interface of Equ c 1 dimer. The recombinant Equ c 1 wild type and the variants were produced and purified to homogeneity, characterized by size-exclusion ultra-high performance liquid chromatography and ultra-high resolution mass spectrometry. The IgE-binding profiles were analyzed by a competitive immunoassay and the biological activity by a histamine release assay using sera from horse allergic individuals. Two Equ c 1 variants, Triple 2 (V47K + V110E + F112K) and Triple 3 (E21Y + V110E + F112K) showed lower allergen-specific IgE-binding capacity and decreased capability to release histamine from basophils in vitro when using sera from six allergic individuals. Triple 3 showed higher reduction than Triple 2 in IgE-binding (5.5 fold) and in histamine release (15.7 fold) compared to wild type Equ c 1. Mutations designed on the putative IgE epitope region and monomer-monomer interface of Equ c 1 resulted in decreased dimerization, a lower IgE-binding capacity and a reduced triggering of an allergic response in vitro.
- Published
- 2019
40. An assessment of side-stream generation from Finnish forest industry
- Author
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Md. Kamrul Hassan, Suvi Kuittinen, Janne Jänis, Aki Villa, and Ari Pappinen
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Side stream ,Pulp (paper) ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,engineering.material ,Pulp and paper industry ,Solid wood ,01 natural sciences ,Mechanics of Materials ,visual_art ,visual_art.visual_art_medium ,engineering ,Environmental science ,Mill ,Woodchips ,021108 energy ,Sawdust ,Forest industry ,Waste Management and Disposal ,Black liquor ,0105 earth and related environmental sciences - Abstract
This study examined side-stream generation from Finnish forest industry comprising data from 19 sawmills, 1 plywood mill, 1 particleboard mill, 10 paper and board mills, 1 semi-mechanical mill, and 15 chemical pulp mills. A structured questionnaire survey was carried out for this study. The results revealed that the generation of side stream in sawmills, plywood mills, paper and board mills, mechanical pulp mills, and chemical pulp mills accounted for 42.2%, 56.1%, 23.8%, 30.7%, and 56% of round wood log input, respectively, and 91.2%, 135.5%, 42.2%, 44.7%, and 238.5% of the finished product, respectively. Woodchips, sawdust, and bark were recognized as the significant side streams in sawmills and plywood mills, whereas fiber sludge was found the main side stream in paper, board and mechanical pulp mills. In chemical pulp mills, black liquor was found the greatest side stream, which comprises 43% of the wood input and 183.3% of the finished product. The study estimated that in 2016, Finnish forest industry generated a total 27.7 million tons of side streams, consisting of 49.2% black liquor, 28.5% solid wood-based waste, 14.1% sludge, 4.4% ashes, and 3.8% others. A current use of these side streams and their future utilization potential is also discussed.
- Published
- 2018
41. Functionalizing Collagen with Vessel‐Penetrating Two‐Photon Phosphorescence Probes: A New In Vivo Strategy to Map Oxygen Concentration in Tumor Microenvironment and Tissue Ischemia
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Elena V. Grachova, Julia R. Shakirova, Yu-Fang Shen, Kristina S. Kisel, Igor O. Koshevoy, Kai-Hsin Chang, Yi-Ting Chen, Pi-Tai Chou, Zhiming Zhang, Janne Jänis, Chia-Yu Chu, Sergey P. Tunik, Tzu-Ming Liu, Cheng-Ham Wu, Pei-Chun Wu, Ming-Rung Tsai, and Muthu Kumar Thangavel
- Subjects
Science ,General Chemical Engineering ,General Physics and Astronomy ,Medicine (miscellaneous) ,Absorption (skin) ,Iridium ,010402 general chemistry ,01 natural sciences ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Two-photon excitation microscopy ,In vivo ,Neoplasms ,Tumor Microenvironment ,Humans ,General Materials Science ,phosphorescence lifetime imaging microscopy ,Research Articles ,tumor hypoxia ,Photons ,Luminescent Agents ,Microscopy, Confocal ,Tumor hypoxia ,010405 organic chemistry ,Chemistry ,General Engineering ,tissue ischemia ,Permeation ,ReI diimine carbonyl complexes ,Extravasation ,3. Good health ,0104 chemical sciences ,Oxygen ,Rhenium ,two‐photon phosphorescence ,Biophysics ,Blood Vessels ,Surface modification ,Collagen ,phosphorescent oxygen sensors ,Phosphorescence ,Research Article - Abstract
The encapsulation and/or surface modification can stabilize and protect the phosphorescence bio‐probes but impede their intravenous delivery across biological barriers. Here, a new class of biocompatible rhenium (ReI) diimine carbonyl complexes is developed, which can efficaciously permeate normal vessel walls and then functionalize the extravascular collagen matrixes as in situ oxygen sensor. Without protective agents, ReI‐diimine complex already exhibits excellent emission yield (34%, λ em = 583 nm) and large two‐photon absorption cross‐sections (σ 2 = 300 GM @ 800 nm) in water (pH 7.4). After extravasation, remarkably, the collagen‐bound probes further enhanced their excitation efficiency by increasing the deoxygenated lifetime from 4.0 to 7.5 µs, paving a way to visualize tumor hypoxia and tissue ischemia in vivo. The post‐extravasation functionalization of extracellular matrixes demonstrates a new methodology for biomaterial‐empowered phosphorescence sensing and imaging., Biocompatible rhenium (ReI) diimine carbonyl complexes functionalize the extravascular collagen matrixes as in situ oxygen sensor. After tail‐vein delivery and vessel penetration, the probe can bind extravascular collagens and achieve stabilization enhanced two‐photon phosphorescence yields. Increased deoxygenated phosphorescence lifetime from 4.0 to 7.5 µs paves a way to visualize tumor hypoxia and tissue ischemia in vivo.
- Published
- 2021
42. Light-driven micro- and nanomotors for environmental remediation
- Author
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Juliane Simmchen, Janne Jänis, and Muhammad Safdar
- Subjects
Engineering ,business.industry ,Environmental remediation ,Materials Science (miscellaneous) ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Light driven ,Nature inspired ,0210 nano-technology ,business ,General Environmental Science - Abstract
Synthetic micro- and nanomotors (MNMs) have emerged as a vibrant research field in multidisciplinary nanotechnology with proof-of-concept applications in various disciplines. In this tutorial review, an overview of the latest achievements towards light-driven MNMs is given and their propulsion mechanisms are introduced. The focus of the paper is on the autonomously propelled MNMs that exploit light-induced physical effects or chemical reactions. Light-induced body deformation, as a completely different, nature inspired concept that is found mostly in soft, polymeric MNMs, is also reviewed. In the end, a few applications of photocatalytic and light-driven MNMs for environmental remediation are presented and their potential is critically discussed.
- Published
- 2017
43. Characterization of fast pyrolysis oil from short-rotation willow by high-resolution Fourier transform ion cyclotron resonance mass spectrometry
- Author
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Ilja Miettinen, Suvi Kuittinen, Marko Mäkinen, Ville Paasikallio, Janne Jänis, and Ari Pappinen
- Subjects
fast pyrolysis ,020209 energy ,General Chemical Engineering ,Electrospray ionization ,Analytical chemistry ,electrospray ionization ,Energy Engineering and Power Technology ,02 engineering and technology ,Photoionization ,Mass spectrometry ,Fourier transform ion cyclotron resonance ,chemistry.chemical_compound ,atmospheric pressure photoionization ,020401 chemical engineering ,Pyrolysis oil ,Ionization ,0202 electrical engineering, electronic engineering, information engineering ,Pyrolytic carbon ,high-resolution mass spectrometry ,0204 chemical engineering ,ta116 ,ta215 ,ta218 ,willow ,Organic Chemistry ,pyrolysis oil ,Fuel Technology ,chemistry ,short-rotation coppice ,fourier transform ion cyclotron resonance ,Pyrolysis - Abstract
Fast pyrolysis oil (FPO) produced from short-rotation willow was characterized by using high-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry and various bulk chemical analyses. The pyrolysis experiments were carried out on a bench-scale bubbling fluidized bed pyrolysis reactor operating at the temperature of 500 °C. The resulting pyrolysis oil was a single-phase liquid with relatively low oxygen content and had pH and total acid number values of 3.0 and 129 mg/g, respectively. A wealth of compositional information of the willow FPO was obtained using FT-ICR MS in combination with electrospray ionization (ESI) and atmospheric-pressure photoionization (APPI) techniques. While ESI preferentially ionized acidic extractives, small phenolics and anhydrosugars, APPI ionized clearly larger compounds, including neutral lipophilic extractives, triterpenoids and high molecular mass pyrolytic lignin, most of which are beyond conventional gas chromatography–mass spectrometry analyses.
- Published
- 2017
44. The Crystal Structure of a Bacterial l -Arabinonate Dehydratase Contains a [2Fe-2S] Cluster
- Author
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Janne Jänis, Mohammad Mubinur Rahman, Merja Penttilä, Martina Andberg, Senthil K. Thangaraj, Nina Hakulinen, Tarja Parkkinen, Juha Rouvinen, and Anu Koivula
- Subjects
Iron-Sulfur Proteins ,Models, Molecular ,0301 basic medicine ,Stereochemistry ,Dimer ,Crystallography, X-Ray ,medicine.disease_cause ,Biochemistry ,Rhizobium leguminosarum ,03 medical and health sciences ,chemistry.chemical_compound ,Tetramer ,Catalytic Domain ,medicine ,ta318 ,Amino Acid Sequence ,Lewis acids and bases ,Phosphorylation ,Hydro-Lyases ,Pentosephosphates ,030102 biochemistry & molecular biology ,biology ,ta1182 ,Active site ,Substrate (chemistry) ,General Medicine ,Lyase ,030104 developmental biology ,chemistry ,Dehydratase ,biology.protein ,Molecular Medicine ,Rhizobium - Abstract
We present a novel crystal structure of the IlvD/EDD family enzyme, l-arabinonate dehydratase from Rhizobium leguminosarum bv. trifolii (RlArDHT, EC 4.2.1.25), which catalyzes the conversion of l-arabinonate to 2-dehydro-3-deoxy-L-arabinonate. The enzyme is a tetramer consisting of a dimer of dimers, where each monomer is composed of two domains. The active site contains a catalytically important [2Fe-2S] cluster and Mg2+ ion and is buried between two domains, and also at the dimer interface. The active site Lys129 was found to be carbamylated. Ser480 and Thr482 were shown to be essential residues for catalysis, and the S480A mutant structure showed an unexpected open conformation in which the active site was more accessible for the substrate. This structure showed the partial binding of L-arabinonate, which allowed us to suggest that the alkoxide ion form of the Ser480 side chain functions as a base and the [2Fe-2S] cluster functions as a Lewis acid in the elimination reaction.
- Published
- 2017
45. Low-Nuclearity Alkynyl d10 Clusters Supported by Chelating Multidentate Phosphines
- Author
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Thuy Minh Dau, Andrey Belyaev, Sergey P. Tunik, Igor O. Koshevoy, Janne Jänis, and Elena V. Grachova
- Subjects
chemistry.chemical_classification ,Denticity ,010405 organic chemistry ,Depolymerization ,Stereochemistry ,Ligand ,Metal ions in aqueous solution ,Organic Chemistry ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Copper ,Medicinal chemistry ,0104 chemical sciences ,Coordination complex ,Inorganic Chemistry ,Metal ,chemistry ,visual_art ,visual_art.visual_art_medium ,Chelation ,Physical and Theoretical Chemistry - Abstract
The coordination chemistry of the tri- and tetradentate chelating phosphines (2-PPh2C6H4)2P(O)Ph (P3O) and (2-PPh2C6H4)3P (P4) with respect to d10 copper subgroup metal ions has been investigated. Depolymerization of (MC2R)n (M = Cu, Ag) with P4 affords the series of mono- and trinuclear complexes (P4)CuC2Ph (1), (P4)Cu3(C2Ph)3 (2), (P4)Ag3(C2Ph) (Hal)2 (Hal = Cl (3), Br (4), I (5)). Reactions of the M+ (M = Cu, Ag) ions with (M′C2R)n (M′ = Cu, Ag, Au) acetylides in the presence of P4 yield the family of dinuclear species [(P4)MM′(C2R)]+ (6–12), which comprise the Cu2/Ag2 (6, 7; R = Ph), AuCu (8–10; R = Ph, C(OH)Me2, C(OH)Ph2), and AuAg (11, 12; R = Ph, C(OH)Ph2) metal cores. A related triphosphine, (2-PPh2C6H4)2PPh (P3), applied in a similar protocol undergoes partial oxidation and leads to the heterotrimetallic clusters [{(P3O)M}2Au(C2R)2]+ (M = Cu, R = C(OH)Ph2, 13; M = Ag, R = C(OH)Ph2, 14; M = Ag, R = Ph, 15), which can be prepared more efficiently starting from the oxidized ligand P3O. The structure...
- Published
- 2016
46. Deciphering metal ion preference and primary coordination sphere robustness of a designed zinc finger with high-resolution mass spectrometry
- Author
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Jarkko Valjakka, István M. Mándity, Mikko Laitaoja, Sari Isoniemi, and Janne Jänis
- Subjects
0301 basic medicine ,Zinc finger ,Coordination sphere ,Chemistry ,Protein design ,Inorganic chemistry ,chemistry.chemical_element ,Zinc ,Biochemistry ,Folding (chemistry) ,03 medical and health sciences ,Crystallography ,030104 developmental biology ,Protein folding ,Molecular Biology ,Histidine ,Binding selectivity - Abstract
Small zinc finger (ZnF) motifs are promising molecular scaffolds for protein design owing to their structural robustness and versatility. Moreover, their characterization provides important insights into protein folding in general. ZnF motifs usually possess an exceptional specificity and high affinity towards Zn(II) ion to drive folding. While the Zn(II) ion is canonically coordinated by two cysteine and two histidine residues, many other coordination spheres also exist in small ZnFs, all having four amino acid ligands. Here we used high-resolution mass spectrometry to study metal ion binding specificity and primary coordination sphere robustness of a designed zinc finger, named MM1. Based on the results, MM1 possesses high specificity for zinc with sub-micromolar binding affinity. Surprisingly, MM1 retains metal ion binding affinity even in the presence of selective alanine mutations of the primary zinc coordinating amino acid residues.
- Published
- 2016
47. UVC-assisted photocatalytic degradation of carbamazepine by Nd-doped Sb
- Author
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Zhao, Wang, Varsha, Srivastava, Shaobin, Wang, Hongqi, Sun, Senthil K, Thangaraj, Janne, Jänis, and Mika, Sillanpää
- Subjects
Neodymium ,Titanium ,Carbamazepine ,Ultraviolet Rays ,Tin Compounds ,Photochemical Processes ,Catalysis - Abstract
The photocatalytic degradation of carbamazepine (CBZ) in ultra-pure water was investigated by using neodymium (Nd)-doped antimony trioxide (Sb
- Published
- 2019
48. Removal of pharmaceutically active compounds (PhACs) from real membrane bioreactor (MBR) effluents by photocatalytic degradation using composite Ag2O/P-25 photocatalyst
- Author
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Janne Jänis, Senthil K. Thangaraj, Mika Sillanpää, Mohamed Chaker Ncibi, Mahdi Seyedsalehi, Khum Gurung, Lappeenrannan-Lahden teknillinen yliopisto LUT, Lappeenranta-Lahti University of Technology LUT, and fi=School of Engineering Science|en=School of Engineering Science
- Subjects
Ag2O/P-25 photocatalysts ,Chemistry ,Filtration and Separation ,02 engineering and technology ,Biodegradation ,021001 nanoscience & nanotechnology ,Membrane bioreactor ,Analytical Chemistry ,Catalysis ,Matrix (chemical analysis) ,020401 chemical engineering ,Wastewater ,Transformation products ,PhACs ,Photocatalysis ,0204 chemical engineering ,0210 nano-technology ,Photodegradation ,Effluent ,Photocatalytic degradation ,Matrix effect ,Nuclear chemistry - Abstract
Pharmaceutically active compounds (PhACs) are emerging pollutants causing serious challenges to wastewater treatment plants due to poor biodegradability. In this study, the enhanced removal of highly recalcitrant and commonly monitored PhACs, carbamazepine (CBZ) and diclofenac (DCF) by heterogeneous photocatalysis was investigated using 5% Ag2O/P-25 photocatalyst. The photocatalyst was characterized by scanning electron microscope (SEM-EDX), Brunauer-Emmett-Teller (BET), Fourier transfer infrared spectroscopy (FTIR) and UV–vis diffuse reflectance spectra (UV-DRS). The effects of catalyst dose, initial pollutants concentration, and mineralization during the photocatalytic degradation of PhACs were investigated. The matrix effect was assessed in deionized water (DW) and real membrane bioreactor effluent (RME). Optimal CBZ and DCF removals of 89.10% and 93.5%, respectively for 180 min of UV irradiation were achieved at catalyst dosage of 0.4 g L−1 in DW matrix. However, the optimal catalyst dosages for CBZ and DCF in RME matrix were increased by factor 2 and 1.5, respectively, to achieve the same degree of removal. Declining trends of removal rate were observed when initial concentrations of both the PhACs were increased under optimal catalyst dosages, and kinetics seem to fit the Langmuir-Hinshelwood model. Photo-induced holes and OH were the dominant oxidation species involved in the photocatalytic degradation of the PhACs. A plausible reusability of 5% Ag2O/P-25 photocatalyst was observed for both the PhACs. Moreover, various aromatic/aliphatic intermediates generated during the photodegradation CBZ were identified using fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry, and a possible multi-step degradation pathway was proposed. Overall, the removal of PhACs using 5% Ag2O/P-25 photocatalyst showed promising results in real wastewater. Post-print / Final draft
- Published
- 2019
49. Luminescent Triphosphine Cyanide d10 Metal Complexes
- Author
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Yi-Ting Chen, Gomathy Chakkaradhari, Antti J. Karttunen, Janne Jänis, Minh Thuy Thuy Dau, Pi-Tai Chou, Igor O. Koshevoy, Mei-Lin Ho, and Sergey P. Tunik
- Subjects
010405 organic chemistry ,Chemistry ,Cyanide ,Inorganic chemistry ,Solid-state ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Metal ,Crystallography ,chemistry.chemical_compound ,visual_art ,visual_art.visual_art_medium ,Density functional theory ,Physical and Theoretical Chemistry ,Luminescence ,Bimetallic strip ,ta116 - Abstract
Coinage metal cyanides efficiently react with a triphosphine. PPh2C6H4-PPh-C6H4PPh2 (P(3)). to give the complexes M(P(3))CN, where M = Cu (1), Ag (2), and Au (3), which can further interact with coordinatively unsaturated metal centers [M(P(3))](+) to give the homobimetallic [(P(3))M-CN-M(P(3))](+)X(-) [M = Cu (4a with X(-) = CF3SO3(-) and 4b with X(-) = BF4(-)), Ag (5)] or heterometallic [(P(3))Au-CN-Ag(P(3))](+) (6) species. Extension of this approach also provided the trinuclear complex [(P(3))Cu-NC-Au-CN-Cu(P(3))](+) (7). Compounds 1-5 were characterized in the solid state by X-ray crystallography. The NMR spectroscopic studies revealed that all of the complexes except 6 retain their structures in solution. The title compounds are luminescent in the solid state, with quantum yields ranging from 8 to 87%. The observed photoemission originates mainly from the metal-to-ligand charge-transfer states according to time-dependent density functional theory computational studies. The crystalline bimetallic Cu complexes 4a/4b demonstrate extremely high sensitivity of the emission intensity to molecular O2 (KSV1 = 639 atm(-1) and LOD = 0.010% for 3 times the signal-to-noise ratio).
- Published
- 2016
50. Dual Effect of Manganese Oxide Micromotors: Catalytic Degradation and Adsorptive Bubble Separation of Organic Pollutants
- Author
-
Janne Jänis, Muhammad Safdar, Niko M. Kinnunen, and Owies M. Wani
- Subjects
Catalytic degradation ,Environmental remediation ,Bubble ,Groundwater remediation ,Inorganic chemistry ,Portable water purification ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Hazardous Substances ,Catalysis ,Water Purification ,Coloring Agents ,Pollutant ,Chemistry ,Organic Chemistry ,Oxides ,General Chemistry ,Human decontamination ,Hydrogen-Ion Concentration ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Manganese Compounds ,0210 nano-technology ,Water Pollutants, Chemical - Abstract
Manganese oxide (MnO2 ) based micromotors exhibiting a dual effect, that is, catalytic degradation and adsorptive bubble separation, were employed for water remediation. The dual effect of MnO2 microparticles led to a greater than 90 % of decolorization of non-biodegradable organic dyes in just 1 h, without the need for external agitation or bubble generation. These findings suggest high potential of MnO2 micromotors for decontamination of organic pollutants from wastewaters or natural water reserves.
- Published
- 2015
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