56 results on '"Janne Jänis"'
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2. Properties and Hydrophobization of Nonwoven-Woven All-Cellulose Composites
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Eija-Katriina Uusi-Tarkka, Eemeli Eronen, Afshan Begum, Janne Jänis, Nawar Kadi, Pooria Khalili, Mikael Skrifvars, Henrik Heräjärvi, and Antti Haapala
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acc ,betulin ,micro-ct ,naoh-urea solvent ,lyocell ,spinnova ,suberin ,Biotechnology ,TP248.13-248.65 - Abstract
All-cellulose composites (ACCs) have been fabricated by using a variety of cellulosic sources, versatile technologies, and are sustainable alternatives for traditional composites. In this study, nonwoven-woven ACC laminates were created from wood-based Spinnova short fibers and Lyocell fabrics via partial dissolution and an NaOH-urea solvent system. The less-known wood-based Spinnova fiber is created for the textile industry, but it also has great potential for the composite industry. To identify the mechanical properties of ACCs—which greatly influence the range of material application—tensile, impact, and flexural tests were conducted. The mechanical properties indicated only moderate properties, which are influenced by high porosity and weak fiber bonding. Despite this, valuable information on the nonwoven-woven structured ACCs was obtained. To improve the ACC laminate’s ability to resist moisture, bio-based coatings (e.g., commercially available birch bark betulin and suberin acid mixture) were applied on the surface of ACCs and it successfully improved the wetting resistance. The results of contact angle analyses demonstrated that the highest contact angle of 128° was measured for betulin-coated laminates and the best stable hydrophobicity calculated a minute after the beginning of the experiment were observed at 109° for the uncommercial pressurized hot ethanol (PHE) extract of birch bark.
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- 2024
3. Robust Approach for Quantifying Glucocorticoid Binding to the Anti-Cortisol Fab Fragment via Native Mass Spectrometry
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Veikko Eronen, Kristiina Iljin, Johan Pääkkönen, Janne Jänis, Juha Rouvinen, Tarja K. Nevanen, and Nina Hakulinen
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Chemistry ,QD1-999 - Published
- 2024
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4. High-Resolution Mass Spectrometry-Based Chemical Fingerprinting of Baijiu, a Traditional Chinese Liquor
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Yanning Dou, Marko Mäkinen, and Janne Jänis
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Chemistry ,QD1-999 - Published
- 2024
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5. Elevated methane alters dissolved organic matter composition in the Arctic Ocean cold seeps
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Muhammed Fatih Sert, Hannah D. Schweitzer, Tim R. de Groot, Timo Kekäläinen, Janne Jänis, Hans C. Bernstein, Bénédicte Ferré, Friederike Gründger, Dimitri Kalenitchenko, and Helge Niemann
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dissolved organic matter ,methane ,cold seeps ,Arctic Ocean ,methane oxidation ,methanotrophs ,Science - Abstract
Cold seeps release methane (CH4) from the seafloor to the water column, which fuels microbially mediated aerobic methane oxidation (MOx). Methane-oxidising bacteria (MOB) utilise excess methane, and the MOB biomass serves as a carbon source in the food web. Yet, it remains unclear if and how MOx modifies the composition of dissolved organic matter (DOM) in cold seeps. We investigated MOx rates, DOM compositions and the microbial community during ex-situ incubations of seawater collected from a cold seep site at Norskebanken (north of the Svalbard archipelago) in the Arctic Ocean. Samples were incubated with and without methane amendments. Samples amended with methane (∼1 µM final concentration) showed elevated rates of MOx in both seep and non-seep incubations. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analyses showed that the number of DOM formulas (i.e., molecular diversity) increased by up to 39% in these incubations. In contrast, the number of formulas decreased by 20% in samples not amended with methane, both from non-seep and seep locations. DOM composition was thus altered towards a more diverse and heterogeneous composition along with elevated methanotrophic activity in methane-amended conditions. In addition to microbial DOM production, abating microbial diversity indicates that elevated DOM diversity was potentially related to grazing pressure on bacteria. The diversity of DOM constituents, therefore, likely increased with the variety of decaying cells contributing to DOM production. Furthermore, based on a principal coordinate analysis, we show that the final DOM composition of non-seep samples amended with methane became more resemblant to that of seep samples. This suggests that methane intrusions will affect water column DOM dynamics similarly, irrespective of the water column’s methane history.
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- 2023
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6. Calculation and Visualization of Binding Equilibria in Protein Studies
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Johan Pääkkönen, Janne Jänis, and Juha Rouvinen
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Chemistry ,QD1-999 - Published
- 2022
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7. 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, and Rajaram Venkatesan
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mycobacterium tuberculosis ,mammalian cell entry proteins ,mce1 ,mce4 ,substrate-binding proteins ,lipids ,abc transporters ,crystal structure ,saxs ,membrane proteins ,protein structure ,x-ray crystallography ,Crystallography ,QD901-999 - Abstract
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
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8. Valorization of Bark from Short Rotation Trees by Temperature-Programmed Slow Pyrolysis
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Qing Zhao, Marko Mäkinen, Antti Haapala, and Janne Jänis
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Chemistry ,QD1-999 - Published
- 2021
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9. 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, and Tuula Jyske
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pyroligneous acid ,hybrid aspen ,biomass ,torrefaction ,biopesticide ,herbicide ,Chemistry ,QD1-999 - 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
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10. Chemical Fingerprinting of Conifer Needle Essential Oils and Solvent Extracts by Ultrahigh-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry
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Omolara O. Mofikoya, Marko Mäkinen, and Janne Jänis
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Chemistry ,QD1-999 - Published
- 2020
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11. Quantitation of Thyroid Hormone Binding to Anti-Thyroxine Antibody Fab Fragment by Native Mass Spectrometry
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Senthil K. Thangaraj, Henri Arola, Antti Tullila, Tarja K. Nevanen, Juha Rouvinen, and Janne Jänis
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Chemistry ,QD1-999 - Published
- 2019
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12. 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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Cheng‐Ham Wu, Kristina S. Kisel, Muthu Kumar Thangavel, Yi‐Ting Chen, Kai‐Hsin Chang, Ming‐Rung Tsai, Chia‐Yu Chu, Yu‐Fang Shen, Pei‐Chun Wu, Zhiming Zhang, Tzu‐Ming Liu, Janne Jänis, Elena V. Grachova, Julia R. Shakirova, Sergey P. Tunik, Igor O. Koshevoy, and Pi‐Tai Chou
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phosphorescence lifetime imaging microscopy ,phosphorescent oxygen sensors ,ReI diimine carbonyl complexes ,tissue ischemia ,tumor hypoxia ,two‐photon phosphorescence ,Science - Abstract
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%, λem = 583 nm) and large two‐photon absorption cross‐sections (σ2 = 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.
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- 2021
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13. Bioconjugation with Aminoalkylhydrazine for Efficient Mass Spectrometry-Based Detection of Small Carbonyl Compounds
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Senthil K. Thangaraj, Sanni Voutilainen, Martina Andberg, Anu Koivula, Janne Jänis, and Juha Rouvinen
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Chemistry ,QD1-999 - Published
- 2019
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14. Characterization of porphobilinogen deaminase mutants reveals that arginine-173 is crucial for polypyrrole elongation mechanism
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Helene J. Bustad, Juha P. Kallio, Mikko Laitaoja, Karen Toska, Inari Kursula, Aurora Martinez, and Janne Jänis
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Biological Sciences ,Biochemistry ,Structural Biology ,Proteomics ,Science - Abstract
Summary: Porphobilinogen deaminase (PBGD), the third enzyme in the heme biosynthesis, catalyzes the sequential coupling of four porphobilinogen (PBG) molecules into a heme precursor. Mutations in PBGD are associated with acute intermittent porphyria (AIP), a rare metabolic disorder. We used Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to demonstrate that wild-type PBGD and AIP-associated mutant R167W both existed as holoenzymes (Eholo) covalently attached to the dipyrromethane cofactor, and three intermediate complexes, ES, ES2, and ES3, where S represents PBG. In contrast, only ES2 was detected in AIP-associated mutant R173W, indicating that the formation of ES3 is inhibited. The R173W crystal structure in the ES2-state revealed major rearrangements of the loops around the active site, compared to wild-type PBGD in the Eholo-state. These results contribute to elucidating the structural pathogenesis of two common AIP-associated mutations and reveal the important structural role of Arg173 in the polypyrrole elongation mechanism.
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- 2021
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15. 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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pyrolysis liquid ,slow pyrolysis ,industrial hemp ,chemical characterization ,NMR ,GC-MS ,Organic chemistry ,QD241-441 - 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
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16. Paclitaxel, Imatinib and 5-Fluorouracil Increase the Unbound Fraction of Flucloxacillin In Vitro
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Maximilian Stolte, Weaam Ali, Janne Jänis, Andre’ Gessner, and Nahed El-Najjar
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albumin ,α-1-acid glycoprotein ,drug-drug interactions ,anti-infective agents ,ultrafiltration ,cancer ,Therapeutics. Pharmacology ,RM1-950 - 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’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 α-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
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17. Identification and characterization of a novel zebrafish (Danio rerio) pentraxin–carbonic anhydrase
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Maarit S. Patrikainen, Martti E.E. Tolvanen, Ashok Aspatwar, Harlan R. Barker, Csaba Ortutay, Janne Jänis, Mikko Laitaoja, Vesa P. Hytönen, Latifeh Azizi, Prajwol Manandhar, Edit Jáger, Daniela Vullo, Sampo Kukkurainen, Mika Hilvo, Claudiu T. Supuran, and Seppo Parkkila
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Phylogeny ,Protein modeling ,Pentraxin ,Zebrafish ,Carbonic anhydrase VI ,Carbonic anhydrase ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background Carbonic anhydrases (CAs) are ubiquitous, essential enzymes which catalyze the conversion of carbon dioxide and water to bicarbonate and H+ ions. Vertebrate genomes generally contain gene loci for 15–21 different CA isoforms, three of which are enzymatically inactive. CA VI is the only secretory protein of the enzymatically active isoforms. We discovered that non-mammalian CA VI contains a C-terminal pentraxin (PTX) domain, a novel combination for both CAs and PTXs. Methods We isolated and sequenced zebrafish (Danio rerio) CA VI cDNA, complete with the sequence coding for the PTX domain, and produced the recombinant CA VI–PTX protein. Enzymatic activity and kinetic parameters were measured with a stopped-flow instrument. Mass spectrometry, analytical gel filtration and dynamic light scattering were used for biophysical characterization. Sequence analyses and Bayesian phylogenetics were used in generating hypotheses of protein structure and CA VI gene evolution. A CA VI–PTX antiserum was produced, and the expression of CA VI protein was studied by immunohistochemistry. A knock-down zebrafish model was constructed, and larvae were observed up to five days post-fertilization (dpf). The expression of ca6 mRNA was quantitated by qRT-PCR in different developmental times in morphant and wild-type larvae and in different adult fish tissues. Finally, the swimming behavior of the morphant fish was compared to that of wild-type fish. Results The recombinant enzyme has a very high carbonate dehydratase activity. Sequencing confirms a 530-residue protein identical to one of the predicted proteins in the Ensembl database (ensembl.org). The protein is pentameric in solution, as studied by gel filtration and light scattering, presumably joined by the PTX domains. Mass spectrometry confirms the predicted signal peptide cleavage and disulfides, and N-glycosylation in two of the four observed glycosylation motifs. Molecular modeling of the pentamer is consistent with the modifications observed in mass spectrometry. Phylogenetics and sequence analyses provide a consistent hypothesis of the evolutionary history of domains associated with CA VI in mammals and non-mammals. Briefly, the evidence suggests that ancestral CA VI was a transmembrane protein, the exon coding for the cytoplasmic domain was replaced by one coding for PTX domain, and finally, in the therian lineage, the PTX-coding exon was lost. We knocked down CA VI expression in zebrafish embryos with antisense morpholino oligonucleotides, resulting in phenotype features of decreased buoyancy and swim bladder deflation in 4 dpf larvae. Discussion These findings provide novel insights into the evolution, structure, and function of this unique CA form.
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- 2017
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18. Co-exposure with fullerene may strengthen health effects of organic industrial chemicals.
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Maili Lehto, Topi Karilainen, Tomasz Róg, Oana Cramariuc, Esa Vanhala, Jarkko Tornaeus, Helena Taberman, Janne Jänis, Harri Alenius, Ilpo Vattulainen, and Olli Laine
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Medicine ,Science - Abstract
In vitro toxicological studies together with atomistic molecular dynamics simulations show that occupational co-exposure with C60 fullerene may strengthen the health effects of organic industrial chemicals. The chemicals studied are acetophenone, benzaldehyde, benzyl alcohol, m-cresol, and toluene which can be used with fullerene as reagents or solvents in industrial processes. Potential co-exposure scenarios include a fullerene dust and organic chemical vapor, or a fullerene solution aerosolized in workplace air. Unfiltered and filtered mixtures of C60 and organic chemicals represent different co-exposure scenarios in in vitro studies where acute cytotoxicity and immunotoxicity of C60 and organic chemicals are tested together and alone by using human THP-1-derived macrophages. Statistically significant co-effects are observed for an unfiltered mixture of benzaldehyde and C60 that is more cytotoxic than benzaldehyde alone, and for a filtered mixture of m-cresol and C60 that is slightly less cytotoxic than m-cresol. Hydrophobicity of chemicals correlates with co-effects when secretion of pro-inflammatory cytokines IL-1β and TNF-α is considered. Complementary atomistic molecular dynamics simulations reveal that C60 co-aggregates with all chemicals in aqueous environment. Stable aggregates have a fullerene-rich core and a chemical-rich surface layer, and while essentially all C60 molecules aggregate together, a portion of organic molecules remains in water.
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- 2014
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19. A novel chimeric avidin with increased thermal stability using DNA shuffling.
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Barbara Taskinen, Tomi T Airenne, Janne Jänis, Rolle Rahikainen, Mark S Johnson, Markku S Kulomaa, and Vesa P Hytönen
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Medicine ,Science - Abstract
Avidins are a family of proteins widely employed in biotechnology. We have previously shown that functional chimeric mutant proteins can be created from avidin and avidin-related protein 2 using a methodology combining random mutagenesis by recombination and selection by a tailored biopanning protocol (phage display). Here, we report the crystal structure of one of the previously selected and characterized chimeric avidin forms, A/A2-1. The structure was solved at 1.8 Å resolution and revealed that the protein fold was not affected by the shuffled sequences. The structure also supports the previously observed physicochemical properties of the mutant. Furthermore, we improved the selection and screening methodology to select for chimeric avidins with slower dissociation rate from biotin than were selected earlier. This resulted in the chimeric mutant A/A2-B, which showed increased thermal stability as compared to A/A2-1 and the parental proteins. The increased stability was especially evident at conditions of extreme pH as characterized using differential scanning calorimetry. In addition, amino acid sequence and structural comparison of the chimeric mutants and the parental proteins led to the rational design of A/A2-B I109K. This mutation further decreased the dissociation rate from biotin and yielded an increase in the thermal stability.
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- 2014
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20. Zebavidin--an avidin-like protein from zebrafish.
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Barbara Taskinen, Joanna Zmurko, Markus Ojanen, Sampo Kukkurainen, Marimuthu Parthiban, Juha A E Määttä, Jenni Leppiniemi, Janne Jänis, Mataleena Parikka, Hannu Turpeinen, Mika Rämet, Marko Pesu, Mark S Johnson, Markku S Kulomaa, Tomi T Airenne, and Vesa P Hytönen
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Medicine ,Science - Abstract
The avidin protein family members are well known for their high affinity towards D-biotin and high structural stability. These properties make avidins valuable tools for a wide range of biotechnology applications. We have identified a new member of the avidin family in the zebrafish (Danio rerio) genome, hereafter called zebavidin. The protein is highly expressed in the gonads of both male and female zebrafish and in the gills of male fish, but our data suggest that zebavidin is not crucial for the developing embryo. Biophysical and structural characterisation of zebavidin revealed distinct properties not found in any previously characterised avidins. Gel filtration chromatography and native mass spectrometry suggest that the protein forms dimers in the absence of biotin at low ionic strength, but assembles into tetramers upon binding biotin. Ligand binding was analysed using radioactive and fluorescently labelled biotin and isothermal titration calorimetry. Moreover, the crystal structure of zebavidin in complex with biotin was solved at 2.4 Å resolution and unveiled unique ligand binding and subunit interface architectures; the atomic-level details support our physicochemical observations.
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- 2013
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21. Characterization of non-specific cytotoxic cell receptor protein 1: a new member of the lectin-type subfamily of F-box proteins.
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Heini Kallio, Martti Tolvanen, Janne Jänis, Pei-wen Pan, Eeva Laurila, Anne Kallioniemi, Sami Kilpinen, Vilppu J Tuominen, Jorma Isola, Jarkko Valjakka, Silvia Pastorekova, Jaromir Pastorek, and Seppo Parkkila
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Medicine ,Science - Abstract
Our previous microarray study showed that the non-specific cytotoxic cell receptor protein 1 (Nccrp1) transcript is significantly upregulated in the gastric mucosa of carbonic anhydrase IX (CA IX)-deficient (Car9(-/-)) mice. In this paper, we aimed to characterize human NCCRP1 and to elucidate its relationship to CA IX. Recombinant NCCRP1 protein was expressed in Escherichia coli, and a novel polyclonal antiserum was raised against the purified full-length protein. Immunocytochemistry showed that NCCRP1 is expressed intracellularly, even though it has previously been described as a transmembrane protein. Using bioinformatic analyses, we identified orthologs of NCCRP1 in 35 vertebrate genomes, and up to five paralogs per genome. These paralogs are FBXO genes whose protein products are components of the E3 ubiquitin ligase complexes. NCCRP1 proteins have no signal peptides or transmembrane domains. NCCRP1 has mainly been studied in fish and was thought to be responsible for the cytolytic function of nonspecific cytotoxic cells (NCCs). Our analyses showed that in humans, NCCRP1 mRNA is expressed in tissues containing squamous epithelium, whereas it shows a more ubiquitous tissue expression pattern in mice. Neither human nor mouse NCCRP1 expression is specific to immune tissues. Silencing CA9 using siRNAs did not affect NCCRP1 levels, indicating that its expression is not directly regulated by CA9. Interestingly, silencing NCCRP1 caused a statistically significant decrease in the growth of HeLa cells. These studies provide ample evidence that the current name, "non-specific cytotoxic cell receptor protein 1," is not appropriate. We therefore propose that the gene name be changed to FBXO50.
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- 2011
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22. Bifunctional avidin with covalently modifiable ligand binding site.
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Jenni Leppiniemi, Juha A E Määttä, Henrik Hammaren, Mikko Soikkeli, Mikko Laitaoja, Janne Jänis, Markku S Kulomaa, and Vesa P Hytönen
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Medicine ,Science - Abstract
The extensive use of avidin and streptavidin in life sciences originates from the extraordinary tight biotin-binding affinity of these tetrameric proteins. Numerous studies have been performed to modify the biotin-binding affinity of (strept)avidin to improve the existing applications. Even so, (strept)avidin greatly favours its natural ligand, biotin. Here we engineered the biotin-binding pocket of avidin with a single point mutation S16C and thus introduced a chemically active thiol group, which could be covalently coupled with thiol-reactive molecules. This approach was applied to the previously reported bivalent dual chain avidin by modifying one binding site while preserving the other one intact. Maleimide was then coupled to the modified binding site resulting in a decrease in biotin affinity. Furthermore, we showed that this thiol could be covalently coupled to other maleimide derivatives, for instance fluorescent labels, allowing intratetrameric FRET. The bifunctional avidins described here provide improved and novel tools for applications such as the biofunctionalization of surfaces.
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- 2011
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23. Transient dimers of allergens.
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Juha Rouvinen, Janne Jänis, Marja-Leena Laukkanen, Sirpa Jylhä, Merja Niemi, Tero Päivinen, Soili Mäkinen-Kiljunen, Tari Haahtela, Hans Söderlund, and Kristiina Takkinen
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Medicine ,Science - Abstract
BACKGROUND: Allergen-mediated cross-linking of IgE antibodies bound to the FcepsilonRI receptors on the mast cell surface is the key feature of the type I allergy. If an allergen is a homodimer, its allergenicity is enhanced because it would only need one type of antibody, instead of two, for cross-linking. METHODOLOGY/PRINCIPAL FINDINGS: An analysis of 55 crystal structures of allergens showed that 80% of them exist in symmetric dimers or oligomers in crystals. The majority are transient dimers that are formed at high protein concentrations that are reached in cells by colocalization. Native mass spectrometric analysis showed that native allergens do indeed form transient dimers in solution, while hypoallergenic variants of them exist almost solely in the monomeric form. We created a monomeric Bos d 5 allergen and show that it has a reduced capability to induce histamine release. CONCLUSIONS/SIGNIFICANCE: The results suggest that dimerization would be a very common and essential feature for allergens. Thus, the preparation of purely monomeric variants of allergens could open up novel possibilities for specific immunotherapy.
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- 2010
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24. 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
25. 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
26. 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
27. 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
28. 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.
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- 2022
29. 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
30. 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
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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
- Full Text
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31. Characterization of fast pyrolysis oil from short-rotation willow by high-resolution Fourier transform ion cyclotron resonance mass spectrometry
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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
32. 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
33. 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
34. 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
35. Structural and functional insights into the unique CBS–CP12 fusion protein family in cyanobacteria
- Author
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Cheryl A. Kerfeld, Svetlana V. Antonyuk, Claudia Hackenberg, Mikko Laitaoja, Johanna Hakanpää, Elke Dittmann, Caroline Eigner, Fei Cai, Sven Meissner, Janne Jänis, and Victor S. Lamzin
- Subjects
0106 biological sciences ,0301 basic medicine ,Cyanobacteria ,inorganic chemicals ,crystal structure ,congenital, hereditary, and neonatal diseases and abnormalities ,Microcystis ,Architecture domain ,1.1 Normal biological development and functioning ,Protein domain ,Cystathionine beta-Synthase ,Computational biology ,01 natural sciences ,Chloroplast Proteins ,03 medical and health sciences ,Bacterial Proteins ,Protein Domains ,Underpinning research ,ddc:570 ,MD Multidisciplinary ,Genetics ,Microcystis aeruginosa ,Gene ,Institut für Biochemie und Biologie ,Multidisciplinary ,biology ,Phosphoribulokinase ,biology.organism_classification ,Fusion protein ,030104 developmental biology ,Multigene Family ,redox ,hexamer ,ddc:500 ,Thioredoxin ,010606 plant biology & botany - Abstract
Proceedings of the National Academy of Sciences of the United States of America 115(27), 7141 - 7146 (2018). doi:10.1073/pnas.1806668115, Cyanobacteria are important photosynthetic organisms inhabiting a range of dynamic environments. This phylum is distinctive among photosynthetic organisms in containing genes encoding uncharacterized cystathionine β-synthase (CBS)–chloroplast protein (CP12) fusion proteins. These consist of two domains, each recognized as stand-alone photosynthetic regulators with different functions described in cyanobacteria (CP12) and plants (CP12 and CBSX). Here we show that CBS–CP12 fusion proteins are encoded in distinct gene neighborhoods, several unrelated to photosynthesis. Most frequently, CBS–CP12 genes are in a gene cluster with thioredoxin A (TrxA), which is prevalent in bloom-forming, marine symbiotic, and benthic mat cyanobacteria. Focusing on a CBS–CP12 from Microcystis aeruginosa PCC 7806 encoded in a gene cluster with TrxA, we reveal that the domain fusion led to the formation of a hexameric protein. We show that the CP12 domain is essential for hexamerization and contains an ordered, previously structurally uncharacterized N-terminal region. We provide evidence that CBS–CP12, while combining properties of both regulatory domains, behaves different from CP12 and plant CBSX. It does not form a ternary complex with phosphoribulokinase (PRK) and glyceraldehyde-3-phosphate dehydrogenase. Instead, CBS–CP12 decreases the activity of PRK in an AMP-dependent manner. We propose that the novel domain architecture and oligomeric state of CBS–CP12 expand its regulatory function beyond those of CP12 in cyanobacteria., Published by National Acad. of Sciences, Washington, DC
- Published
- 2018
36. Identification and characterization of a novel zebrafish (Danio rerio) pentraxin–carbonic anhydrase
- Author
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Latifeh Azizi, Vesa P. Hytönen, Edit Jáger, Csaba Ortutay, Ashok Aspatwar, Prajwol Manandhar, Janne Jänis, Sampo Kukkurainen, Mikko Laitaoja, Martti Tolvanen, Daniela Vullo, Harlan Barker, Seppo Parkkila, Maarit S. Patrikainen, Mika Hilvo, Claudiu T. Supuran, Lääketieteen ja biotieteiden tiedekunta - Faculty of Medicine and Life Sciences, University of Tampere, and Department of Chemistry, activities
- Subjects
0301 basic medicine ,Gene isoform ,Signal peptide ,Bioinformatics ,Carbonic anhydrase VI ,lcsh:Medicine ,Biochemistry ,General Biochemistry, Genetics and Molecular Biology ,Biokemia, solu- ja molekyylibiologia - Biochemistry, cell and molecular biology ,03 medical and health sciences ,Protein structure ,Carbonic anhydrase ,Complementary DNA ,Carbonate dehydratase activity ,Zebrafish ,Phylogeny ,Innate immunity ,ta113 ,Mass spectrometry ,030102 biochemistry & molecular biology ,biology ,Chemistry ,General Neuroscience ,lcsh:R ,Morphant ,Pentraxin ,General Medicine ,biology.organism_classification ,Evolutionary Studies ,3. Good health ,030104 developmental biology ,biology.protein ,Knockdown ,Protein modeling ,General Agricultural and Biological Sciences - Abstract
Background Carbonic anhydrases (CAs) are ubiquitous, essential enzymes which catalyze the conversion of carbon dioxide and water to bicarbonate and H+ ions. Vertebrate genomes generally contain gene loci for 15–21 different CA isoforms, three of which are enzymatically inactive. CA VI is the only secretory protein of the enzymatically active isoforms. We discovered that non-mammalian CA VI contains a C-terminal pentraxin (PTX) domain, a novel combination for both CAs and PTXs. Methods We isolated and sequenced zebrafish (Danio rerio) CA VI cDNA, complete with the sequence coding for the PTX domain, and produced the recombinant CA VI–PTX protein. Enzymatic activity and kinetic parameters were measured with a stopped-flow instrument. Mass spectrometry, analytical gel filtration and dynamic light scattering were used for biophysical characterization. Sequence analyses and Bayesian phylogenetics were used in generating hypotheses of protein structure and CA VI gene evolution. A CA VI–PTX antiserum was produced, and the expression of CA VI protein was studied by immunohistochemistry. A knock-down zebrafish model was constructed, and larvae were observed up to five days post-fertilization (dpf). The expression of ca6 mRNA was quantitated by qRT-PCR in different developmental times in morphant and wild-type larvae and in different adult fish tissues. Finally, the swimming behavior of the morphant fish was compared to that of wild-type fish. Results The recombinant enzyme has a very high carbonate dehydratase activity. Sequencing confirms a 530-residue protein identical to one of the predicted proteins in the Ensembl database (ensembl.org). The protein is pentameric in solution, as studied by gel filtration and light scattering, presumably joined by the PTX domains. Mass spectrometry confirms the predicted signal peptide cleavage and disulfides, and N-glycosylation in two of the four observed glycosylation motifs. Molecular modeling of the pentamer is consistent with the modifications observed in mass spectrometry. Phylogenetics and sequence analyses provide a consistent hypothesis of the evolutionary history of domains associated with CA VI in mammals and non-mammals. Briefly, the evidence suggests that ancestral CA VI was a transmembrane protein, the exon coding for the cytoplasmic domain was replaced by one coding for PTX domain, and finally, in the therian lineage, the PTX-coding exon was lost. We knocked down CA VI expression in zebrafish embryos with antisense morpholino oligonucleotides, resulting in phenotype features of decreased buoyancy and swim bladder deflation in 4 dpf larvae. Discussion These findings provide novel insights into the evolution, structure, and function of this unique CA form., published version, peerReviewed
- Published
- 2017
37. Ferrocenyl-functionalized tetranuclear gold(I) and gold(I)-copper(I) complexes based on tridentate phosphanes
- Author
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Thuy Minh Dau, Matti Haukka, Janne Jänis, Tapani A. Pakkanen, Antonio Doménech, Sergey P. Tunik, Igor O. Koshevoy, Elena V. Grachova, and Julia R. Shakirova
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Chemistry ,Stereochemistry ,chemistry.chemical_element ,Trigonal pyramidal molecular geometry ,Nuclear magnetic resonance spectroscopy ,Electrochemistry ,Redox ,Copper ,Inorganic Chemistry ,Metal ,Electron transfer ,chemistry.chemical_compound ,Crystallography ,Triphosphane ,visual_art ,visual_art.visual_art_medium ,ta116 - Abstract
Tetranuclear AuI–FeII dimetallic and AuI–CuI–FeII trimetallic complexes bearing ferrocenyl (Fc) groups have been assembled by using two triphosphane ligands, namely, (PPh2CH2)2PPh (dpmp) and (PPh2)3CH (tppm). The compositions and structural type of the clusters are dependent on the stereochemistry of the P donor ligands. The complexes [tppmAu3Cu(C2R)3]PF6 [R = Fc (1) and 4-C6H4-Fc (2)] adopt a trigonal pyramidal {Au3Cu} arrangement of the coordinating metal core, whereas for the compounds with the linear triphosphane [Au4(dpmp)2(C2R)2](PF6)2 [R = Fc (3) and 4-C6H4-Fc (4)], a planar rhomboidal {Au4} framework was found. Clusters 1–4 were characterized by NMR spectroscopy and ESI-MS measurements. The solid-state structures of 1, 3, and 4 have been determined by X-ray crystallography. The electrochemical properties of 1–4 were studied and revealed redox processes attributed to the Fc functions. Oxidation of the Fc units in 1, 2, and 4 occurs independently. In 3, an electron transfer process mediated by the {Au4} metal core was observed.
- Published
- 2013
38. Preliminary X-ray analysis of twinned crystals of sarcosine dimethylglycine methyltransferase from Halorhodospira halochoris
- Author
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Juha Rouvinen, Juha P. Kallio, Antti Nyyssölä, Janne Jänis, and Nina Hakulinen
- Subjects
Sarcosine ,Twinning ,Protein Conformation ,Stereochemistry ,Biophysics ,Crystallography, X-Ray ,Biochemistry ,Mass Spectrometry ,law.invention ,Dimethylglycine ,Crystal ,chemistry.chemical_compound ,Tetragonal crystal system ,Betaine ,Bacterial Proteins ,Structural Biology ,law ,Genetics ,Crystallization ,Fourier Analysis ,Chemistry ,Methyltransferases ,Condensed Matter Physics ,Recombinant Proteins ,Crystallography ,Crystallization Communications ,Halorhodospira halochoris ,Sarcosine dimethylglycine methyltransferase ,Orthorhombic crystal system ,Ectothiorhodospiraceae ,Monoclinic crystal system - Abstract
Sarcosine dimethylglycine methyltransferase (EC 2.1.1.157) is an enzyme from the extremely halophilic anaerobic bacterium Halorhodospira halochoris. This enzyme catalyzes the twofold methylation of sarcosine to betaine, with S-adenosylmethionine (AdoMet) as the methyl-group donor. This study presents the crystallization and preliminary X-ray analysis of recombinant sarcosine dimethylglycine methyltransferase produced in Escherichia coli. Mass spectroscopy was used to determine the purity and homogeneity of the enzyme material. Two different crystal forms, which initially appeared to be hexagonal and tetragonal, were obtained. However, on analyzing the diffraction data it was discovered that both crystal forms were pseudo-merohedrally twinned. The true crystal systems were monoclinic and orthorhombic. The monoclinic crystal diffracted to a maximum of 2.15 Å resolution and the orthorhombic crystal diffracted to 1.8 Å resolution.
- Published
- 2009
39. Characterization and crystallization of a recombinant IgE Fab fragment in complex with the bovine [beta]-lactoglobulin allergen
- Author
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Marja-Leena Laukkanen, Johanna Kallio, Nina Hakulinen, Janne Jänis, Kristiina Takkinen, Juha Rouvinen, Merja Niemi, and Sirpa Jylhä
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Resolution (mass spectrometry) ,Stereochemistry ,Molecular Sequence Data ,Biophysics ,Lactoglobulins ,Crystallography, X-Ray ,Mass spectrometry ,Immunoglobulin E ,Biochemistry ,Antibodies ,law.invention ,Immunoglobulin Fab Fragments ,Structural Biology ,law ,Hypersensitivity ,Genetics ,Animals ,Humans ,Amino Acid Sequence ,Lymphocytes ,Child ,Peptide sequence ,biology ,Chemistry ,Spectrum Analysis ,food and beverages ,Allergens ,Condensed Matter Physics ,Crystallization Communications ,biology.protein ,Recombinant DNA ,Food allergens ,Immunoglobulin heavy chain ,Cattle ,Immunoglobulin Light Chains ,Orthorhombic crystal system ,IgE ,Immunoglobulin Heavy Chains ,Food Hypersensitivity - Abstract
A D1 Fab fragment containing the allergen-binding variable domains of the IgE antibody was characterized by ESI FT-ICR mass spectrometry and crystallized with bovine beta-lactoglobulin (BLG) using the hanging-drop vapour-diffusion method at 293 K. X-ray data suitable for structure determination were collected to 2.8 A resolution using synchrotron radiation. The crystal belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 67.0, b = 100.6, c = 168.1 A. The three-dimensional structure of the D1 Fab fragment-BLG complex will provide the first insight into IgE antibody-allergen interactions at the molecular level.
- Published
- 2008
40. Dimerization of lipocalin allergens
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Marja Rytkönen-Nissinen, Janne Jänis, Merja Niemi, Ilja Miettinen, Tuomas Virtanen, and Juha Rouvinen
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Intoxicative inhalant ,Models, Molecular ,Protein Conformation ,Dimer ,Lipocalin ,medicine.disease_cause ,Article ,Mass Spectrometry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Allergen ,Protein structure ,medicine ,030304 developmental biology ,0303 health sciences ,Multidisciplinary ,integumentary system ,Chemistry ,Allergens ,Protein multimerization ,humanities ,Lipocalins ,3. Good health ,Animal allergens ,Biochemistry ,Protein Multimerization ,030217 neurology & neurosurgery - Abstract
Lipocalins are one of the most important groups of inhalant animal allergens. The analysis of structural features of these proteins is important to get insights into their allergenicity. We have determined two different dimeric crystal structures for bovine dander lipocalin Bos d 2, which was earlier described as a monomeric allergen. The crystal structure analysis of all other determined lipocalin allergens also revealed oligomeric structures which broadly utilize inherent structural features of the β-sheet in dimer formation. According to the moderate size of monomer-monomer interfaces, most of these dimers would be transient in solution. Native mass spectrometry was employed to characterize quantitatively transient dimerization of two lipocalin allergens, Bos d 2 and Bos d 5, in solution.
- Published
- 2015
41. A novel chimeric avidin with increased thermal stability using DNA shuffling
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Markku S. Kulomaa, Barbara Taskinen, Tomi T. Airenne, Janne Jänis, Rolle Rahikainen, Mark S. Johnson, Vesa P. Hytönen, BioMediTech - BioMediTech, and University of Tampere
- Subjects
Models, Molecular ,Proteomics ,Phage display ,Mutant ,lcsh:Medicine ,Crystallography, X-Ray ,Protein Engineering ,Biochemistry ,chemistry.chemical_compound ,Biotin ,Nucleic Acids ,Lääketieteen bioteknologia - Medical biotechnology ,Biomacromolecule-Ligand Interactions ,lcsh:Science ,Peptide sequence ,0303 health sciences ,Multidisciplinary ,biology ,Protein Stability ,Chemistry ,030302 biochemistry & molecular biology ,Temperature ,Recombinant Proteins ,DNA shuffling ,DNA modification ,Research Article ,Biotechnology ,Protein Structure ,DNA recombination ,Recombinant Fusion Proteins ,Molecular Sequence Data ,Biophysics ,Mutagenesis (molecular biology technique) ,Bioengineering ,Biopanning ,03 medical and health sciences ,Genetics ,Amino Acid Sequence ,Protein Structure, Quaternary ,030304 developmental biology ,Biology and life sciences ,lcsh:R ,Proteins ,DNA Shuffling ,DNA ,Avidin ,Mutagenesis ,Mutation ,biology.protein ,lcsh:Q ,Protein Multimerization - Abstract
Avidins are a family of proteins widely employed in biotechnology. We have previously shown that functional chimeric mutant proteins can be created from avidin and avidin-related protein 2 using a methodology combining random mutagenesis by recombination and selection by a tailored biopanning protocol (phage display). Here, we report the crystal structure of one of the previously selected and characterized chimeric avidin forms, A/A2-1. The structure was solved at 1.8 Å resolution and revealed that the protein fold was not affected by the shuffled sequences. The structure also supports the previously observed physicochemical properties of the mutant. Furthermore, we improved the selection and screening methodology to select for chimeric avidins with slower dissociation rate from biotin than were selected earlier. This resulted in the chimeric mutant A/A2-B, which showed increased thermal stability as compared to A/A2-1 and the parental proteins. The increased stability was especially evident at conditions of extreme pH as characterized using differential scanning calorimetry. In addition, amino acid sequence and structural comparison of the chimeric mutants and the parental proteins led to the rational design of A/A2-B I109K. This mutation further decreased the dissociation rate from biotin and yielded an increase in the thermal stability. Public Library of Science open access
- Published
- 2014
42. Co-exposure with fullerene may strengthen health effects of organic industrial chemicals
- Author
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Harri Alenius, Janne Jänis, Topi Karilainen, Helena Taberman, Jarkko Tornaeus, Oana Cramariuc, Esa Vanhala, Tomasz Róg, Maili Lehto, Ilpo Vattulainen, and Olli Laine
- Subjects
Light ,Cytotoxicity ,Interleukin-1beta ,lcsh:Medicine ,02 engineering and technology ,010501 environmental sciences ,Toxicology ,Molecular Dynamics ,01 natural sciences ,Mass Spectrometry ,POLYCYCLIC AROMATIC-HYDROCARBONS IN-VITRO EVALUATION MOLECULAR-DYNAMICS AQUEOUS SUSPENSIONS C-60 TOXICITY NANOPARTICLES EXPOSURE DISTRIBUTIONS DISPERSIONS ,Analytical Chemistry ,Scattering ,chemistry.chemical_compound ,Cresols ,Computational Chemistry ,Immunotoxicology ,Organic chemistry ,Nanotechnology ,Drug Interactions ,Electron Microscopy ,lcsh:Science ,Microscopy ,Multidisciplinary ,Aqueous solution ,Organic Compounds ,Physics ,Electromagnetic Radiation ,Electrospray Ionization Mass Spectrometry ,021001 nanoscience & nanotechnology ,3. Good health ,Chemistry ,Benzyl alcohol ,Benzaldehydes ,Physical Sciences ,Thermodynamics ,Engineering and Technology ,Fullerenes ,0210 nano-technology ,Hydrophobic and Hydrophilic Interactions ,Acetophenone ,Research Article ,Fullerene ,Liquid Chromatography-Mass Spectrometry ,Air Pollutants, Occupational ,Molecular Dynamics Simulation ,Research and Analysis Methods ,Benzaldehyde ,Cell Line, Tumor ,Humans ,0105 earth and related environmental sciences ,Nanomaterials ,business.industry ,Tumor Necrosis Factor-alpha ,Macrophages ,Organic Chemistry ,lcsh:R ,Chemical Compounds ,Light Scattering ,Acetophenones ,Biology and Life Sciences ,Chemical industry ,Toluene ,chemistry ,13. Climate action ,Reagent ,Nanoparticles ,Transmission Electron Microscopy ,lcsh:Q ,business ,Benzyl Alcohol - Abstract
In vitro toxicological studies together with atomistic molecular dynamics simulations show that occupational co-exposure with C-60 fullerene may strengthen the health effects of organic industrial chemicals. The chemicals studied are acetophenone, benzaldehyde, benzyl alcohol, m-cresol, and toluene which can be used with fullerene as reagents or solvents in industrial processes. Potential co-exposure scenarios include a fullerene dust and organic chemical vapor, or a fullerene solution aerosolized in workplace air. Unfiltered and filtered mixtures of C-60 and organic chemicals represent different co-exposure scenarios in in vitro studies where acute cytotoxicity and immunotoxicity of C-60 and organic chemicals are tested together and alone by using human THP-1-derived macrophages. Statistically significant co-effects are observed for an unfiltered mixture of benzaldehyde and C-60 that is more cytotoxic than benzaldehyde alone, and for a filtered mixture of m-cresol and C-60 that is slightly less cytotoxic than m-cresol. Hydrophobicity of chemicals correlates with co-effects when secretion of pro-inflammatory cytokines IL-1 beta and TNF-alpha is considered. Complementary atomistic molecular dynamics simulations reveal that C-60 co-aggregates with all chemicals in aqueous environment. Stable aggregates have a fullerene-rich core and a chemical-rich surface layer, and while essentially all C-60 molecules aggregate together, a portion of organic molecules remains in water.
- Published
- 2014
43. Zebavidin--an avidin-like protein from zebrafish
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Vesa P. Hytönen, Markus J. T. Ojanen, Mark S. Johnson, Markku S. Kulomaa, Joanna Zmurko, Marko Pesu, M Parthiban, Mataleena Parikka, Hannu Turpeinen, Sampo Kukkurainen, Barbara Taskinen, Jenni Leppiniemi, Juha A. E. Määttä, Janne Jänis, Tomi T. Airenne, Mika Rämet, BioMediTech - BioMediTech, and University of Tampere
- Subjects
Gills ,Male ,Models, Molecular ,Embryo, Nonmammalian ,Gene Expression ,lcsh:Medicine ,Plasma protein binding ,Crystallography, X-Ray ,chemistry.chemical_compound ,Biotin ,Protein Isoforms ,lcsh:Science ,Zebrafish ,Peptide sequence ,0303 health sciences ,Genome ,Multidisciplinary ,biology ,030302 biochemistry & molecular biology ,Recombinant Proteins ,Biochemistry ,Female ,Protein Binding ,Research Article ,Fish Proteins ,animal structures ,Protein family ,Biolääketieteet - Biomedicine ,Protein subunit ,Molecular Sequence Data ,03 medical and health sciences ,Escherichia coli ,Animals ,Amino Acid Sequence ,Gonads ,Glycoproteins ,030304 developmental biology ,Sequence Homology, Amino Acid ,lcsh:R ,Isothermal titration calorimetry ,Zebrafish Proteins ,Avidin ,biology.organism_classification ,chemistry ,biology.protein ,lcsh:Q ,Protein Multimerization ,Sequence Alignment - Abstract
The avidin protein family members are well known for their high affinity towards D-biotin and high structural stability. These properties make avidins valuable tools for a wide range of biotechnology applications. We have identified a new member of the avidin family in the zebrafish (Danio rerio) genome, hereafter called zebavidin. The protein is highly expressed in the gonads of both male and female zebrafish and in the gills of male fish, but our data suggest that zebavidin is not crucial for the developing embryo. Biophysical and structural characterisation of zebavidin revealed distinct properties not found in any previously characterised avidins. Gel filtration chromatography and native mass spectrometry suggest that the protein forms dimers in the absence of biotin at low ionic strength, but assembles into tetramers upon binding biotin. Ligand binding was analysed using radioactive and fluorescently labelled biotin and isothermal titration calorimetry. Moreover, the crystal structure of zebavidin in complex with biotin was solved at 2.4 Å resolution and unveiled unique ligand binding and subunit interface architectures; the atomic-level details support our physicochemical observations. Public Library of Science open access
- Published
- 2013
44. Characterization of Non-Specific Cytotoxic Cell Receptor Protein 1: A New Member of the Lectin-Type Subfamily of F-Box Proteins
- Author
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Anne Kallioniemi, Heini Kallio, Janne Jänis, Peiwen Pan, Vilppu J. Tuominen, Martti Tolvanen, Eeva Laurila, Jaromir Pastorek, Seppo Parkkila, Jarkko Valjakka, Jorma Isola, Silvia Pastorekova, and Sami Kilpinen
- Subjects
Signal peptide ,Evolutionary Genetics ,Ubiquitin-Protein Ligases ,Protein domain ,Immunology ,lcsh:Medicine ,Gene Expression ,F-box protein ,Biochemistry ,Protein Chemistry ,Molecular Genetics ,Mice ,Antigens, Neoplasm ,Lectins ,Gene expression ,Molecular Cell Biology ,Genetics ,Gene silencing ,Animals ,Humans ,Tissue Distribution ,RNA, Messenger ,lcsh:Science ,Immunoassays ,Carbonic Anhydrase IX ,Biology ,Phylogeny ,Carbonic Anhydrases ,Evolutionary Biology ,Multidisciplinary ,biology ,F-Box Proteins ,lcsh:R ,Proteins ,Computational Biology ,Molecular biology ,Transmembrane protein ,Recombinant Proteins ,Ubiquitin ligase ,Transmembrane domain ,Receptors, Antigen ,biology.protein ,Immunologic Techniques ,Medicine ,lcsh:Q ,Clinical Immunology ,Research Article ,HeLa Cells - Abstract
Our previous microarray study showed that the non-specific cytotoxic cell receptor protein 1 (Nccrp1) transcript is significantly upregulated in the gastric mucosa of carbonic anhydrase IX (CA IX)-deficient (Car9(-/-)) mice. In this paper, we aimed to characterize human NCCRP1 and to elucidate its relationship to CA IX. Recombinant NCCRP1 protein was expressed in Escherichia coli, and a novel polyclonal antiserum was raised against the purified full-length protein. Immunocytochemistry showed that NCCRP1 is expressed intracellularly, even though it has previously been described as a transmembrane protein. Using bioinformatic analyses, we identified orthologs of NCCRP1 in 35 vertebrate genomes, and up to five paralogs per genome. These paralogs are FBXO genes whose protein products are components of the E3 ubiquitin ligase complexes. NCCRP1 proteins have no signal peptides or transmembrane domains. NCCRP1 has mainly been studied in fish and was thought to be responsible for the cytolytic function of nonspecific cytotoxic cells (NCCs). Our analyses showed that in humans, NCCRP1 mRNA is expressed in tissues containing squamous epithelium, whereas it shows a more ubiquitous tissue expression pattern in mice. Neither human nor mouse NCCRP1 expression is specific to immune tissues. Silencing CA9 using siRNAs did not affect NCCRP1 levels, indicating that its expression is not directly regulated by CA9. Interestingly, silencing NCCRP1 caused a statistically significant decrease in the growth of HeLa cells. These studies provide ample evidence that the current name, "non-specific cytotoxic cell receptor protein 1," is not appropriate. We therefore propose that the gene name be changed to FBXO50.
- Published
- 2011
45. Bifunctional Avidin with Covalently Modifiable Ligand Binding Site
- Author
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Juha A. E. Määttä, Jenni Leppiniemi, Mikko Soikkeli, Henrik Hammaren, Markku S. Kulomaa, Vesa P. Hytönen, Janne Jänis, Mikko Laitaoja, Biolääketieteellisen teknologian yksikkö - Institute of Biomedical Technology, and University of Tampere
- Subjects
Streptavidin ,Macromolecular Assemblies ,Proteomics ,Biophysics ,lcsh:Medicine ,Biotin ,Protein Engineering ,Ligands ,Biochemistry ,Protein Chemistry ,Biokemia, solu- ja molekyylibiologia - Biochemistry, cell and molecular biology ,03 medical and health sciences ,chemistry.chemical_compound ,Chemical Biology ,Point Mutation ,Sulfhydryl Compounds ,Binding site ,Biomacromolecule-Ligand Interactions ,lcsh:Science ,Bifunctional ,Maleimide ,Biology ,030304 developmental biology ,0303 health sciences ,Multidisciplinary ,Binding Sites ,biology ,lcsh:R ,030302 biochemistry & molecular biology ,Proteins ,Ligand (biochemistry) ,Avidin ,Combinatorial chemistry ,Recombinant Proteins ,Cross-Linking Reagents ,chemistry ,Small Molecules ,Biotinylation ,Bionanotechnology ,biology.protein ,lcsh:Q ,Genetic Engineering ,Research Article ,Biotechnology - Abstract
The extensive use of avidin and streptavidin in life sciences originates from the extraordinary tight biotin-binding affinity of these tetrameric proteins. Numerous studies have been performed to modify the biotin-binding affinity of (strept)avidin to improve the existing applications. Even so, (strept)avidin greatly favours its natural ligand, biotin. Here we engineered the biotin-binding pocket of avidin with a single point mutation S16C and thus introduced a chemically active thiol group, which could be covalently coupled with thiol-reactive molecules. This approach was applied to the previously reported bivalent dual chain avidin by modifying one binding site while preserving the other one intact. Maleimide was then coupled to the modified binding site resulting in a decrease in biotin affinity. Furthermore, we showed that this thiol could be covalently coupled to other maleimide derivatives, for instance fluorescent labels, allowing intratetrameric FRET. The bifunctional avidins described here provide improved and novel tools for applications such as the biofunctionalization of surfaces. Public Library of Science
- Published
- 2011
46. Transient dimers of allergens
- Author
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Janne Jänis, Tero Päivinen, Tari Haahtela, Sirpa Jylhä, Juha Rouvinen, Marja-Leena Laukkanen, Kristiina Takkinen, Hans Söderlund, Soili Mäkinen-Kiljunen, Merja Niemi, and Department of Dermatology, Allergology and Venereology
- Subjects
Models, Molecular ,lcsh:Medicine ,312 Clinical medicine ,medicine.disease_cause ,Immunoglobulin E ,Crystallography, X-Ray ,Cross-reactivity ,Histamine Release ,Mass Spectrometry ,law.invention ,0302 clinical medicine ,Allergen ,law ,BET V 1 ,immune system diseases ,CRYSTAL-STRUCTURE ,lcsh:Science ,Receptor ,BIRCH POLLEN ALLERGEN ,Biochemistry/Experimental Biophysical Methods ,Plant Proteins ,0303 health sciences ,Multidisciplinary ,biology ,MACROMOLECULAR ASSEMBLIES ,respiratory system ,Mast cell ,3. Good health ,Basophils ,medicine.anatomical_structure ,Biochemistry/Macromolecular Assemblies and Machines ,CROSS-REACTIVITY ,Recombinant DNA ,Antibody ,Immunology/Allergy and Hypersensitivity ,Crystallization ,Research Article ,Antigens, Fungal ,MAJOR ALLERGEN ,education ,Protein–protein interaction ,03 medical and health sciences ,medicine ,otorhinolaryngologic diseases ,Animals ,Humans ,IGE ,Protein Structure, Quaternary ,030304 developmental biology ,lcsh:R ,MASS-SPECTROMETRY ,Allergens ,Antigens, Plant ,PROTEIN INTERACTIONS ,respiratory tract diseases ,Immunology ,Mutation ,biology.protein ,X-RAY ,lcsh:Q ,Cattle ,Protein Multimerization ,030215 immunology - Abstract
BackgroundAllergen-mediated cross-linking of IgE antibodies bound to the FcεRI receptors on the mast cell surface is the key feature of the type I allergy. If an allergen is a homodimer, its allergenicity is enhanced because it would only need one type of antibody, instead of two, for cross-linking.Methodology/Principal FindingsAn analysis of 55 crystal structures of allergens showed that 80% of them exist in symmetric dimers or oligomers in crystals. The majority are transient dimers that are formed at high protein concentrations that are reached in cells by colocalization. Native mass spectrometric analysis showed that native allergens do indeed form transient dimers in solution, while hypoallergenic variants of them exist almost solely in the monomeric form. We created a monomeric Bos d 5 allergen and show that it has a reduced capability to induce histamine release.Conclusions/SignificanceThe results suggest that dimerization would be a very common and essential feature for allergens. Thus, the preparation of purely monomeric variants of allergens could open up novel possibilities for specific immunotherapy.
- Published
- 2010
47. Improving the thermostability and activity of <em class='EmphasisTypeItalic'>Melanocarpus albomyces cellobiohydrolase Cel7B
- Author
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Jari Vehmaanperä, Janne Jänis, Sanni Voutilainen, Harry Boer, Marika Alapuranen, and Anu Koivula
- Subjects
Hot Temperature ,Stereochemistry ,Mutant ,Sordariales ,Cellulase ,Protein Engineering ,Applied Microbiology and Biotechnology ,Fungal Proteins ,chemistry.chemical_compound ,Hydrolysis ,Enzyme Stability ,Cellulose 1,4-beta-Cellobiosidase ,Cellulose ,Site-directed mutagenesis ,Trichoderma reesei ,Thermostability ,biology ,Active site ,General Medicine ,biology.organism_classification ,Kinetics ,chemistry ,Biochemistry ,Saccharomyces cerevisiae expression ,biology.protein ,Protein engineering ,Biotechnology - Abstract
Two different types of approach were taken to improve the hydrolytic activity towards crystalline cellulose at elevated temperatures of Melanocarpus albomyces Cel7B (Ma Cel7B), a single-module GH-7 family cellobiohydrolase. Structure-guided protein engineering was used to introduce an additional tenth disulphide bridge to the Ma Cel7B catalytic module. In addition, a fusion protein was constructed by linking a cellulose-binding module (CBM) and a linker from the Trichoderma reesei Cel7A to the C terminus of Ma Cel7B. Both approaches proved successful. The disulphide bridge mutation G4C/M70C located near the N terminus, close to the entrance of the active site tunnel of Ma Cel7B, led to improved thermostability (ΔT m = 2.5°C). By adding the earlier found thermostability-increasing mutation S290T (ΔT m = 1.5°C) together with the disulphide bridge mutation, the unfolding temperature was increased by 4°C (mutant G4C/M70C/S290T) compared to that of the wild-type enzyme, thus showing an additive effect on thermostability. Both disulphide mutants had increased activity towards microcrystalline cellulose (Avicel) at 75°C, apparently solely because of their improved thermostability. The addition of a CBM also improved the thermostability (ΔT m = 2.5°C) and caused a clear (sevenfold) increase in the hydrolysis activity of Ma Cel7B towards Avicel at 70°C.
- Published
- 2009
48. Biochemical characterization of CA IX, one of the most active carbonic anhydrase isozymes
- Author
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Janne Jänis, Andrea Scaloni, Seppo Parkkila, Anna Di Fiore, Lina Baranauskiene, Simona Maria Monti, Mikaela Lindfors, Markku S. Kulomaa, Giuseppina De Simone, Jarkko Valjakka, Anna Maria Salzano, Alessio Innocenti, Henri R. Nordlund, Mika Hilvo, Silvia Pastorekova, Daumantas Matulis, Claudiu T. Supuran, Andrea Scozzafava, and Jaromir Pastorek
- Subjects
Glycosylation ,Protein family ,Spodoptera ,Biochemistry ,Catalysis ,Cell Line ,chemistry.chemical_compound ,Protein structure ,Antigens, Neoplasm ,Polysaccharides ,Carbonic anhydrase ,Neoplasms ,Extracellular ,Cell Adhesion ,Animals ,Humans ,Disulfides ,Carbonic Anhydrase IX ,Molecular Biology ,Carbonic Anhydrases ,Cell Proliferation ,chemistry.chemical_classification ,biology ,Chemistry ,hypoxia ,biochemical characterization ,CAIX ,Cell Biology ,Hydrogen-Ion Concentration ,Transmembrane protein ,Recombinant Proteins ,Protein Structure, Tertiary ,Isoenzymes ,Enzyme ,Membrane protein ,biology.protein ,Baculoviridae ,Dimerization - Abstract
Carbonic anhydrase IX (CA IX) is an exceptional member of the CA protein family; in addition to its classical role in pH regulation, it has also been proposed to participate in cell proliferation, cell adhesion, and tumorigenic processes. To characterize the biochemical properties of this membrane protein, two soluble recombinant forms were produced using the baculovirus-insect cell expression system. The recombinant proteins consisted of either the CA IX catalytic domain only (CA form) or the extracellular domain, which included both the proteoglycan and catalytic domains (PG + CA form). The produced proteins lacked the small transmembrane and intracytoplasmic regions of CA IX. Stopped-flow spectrophotometry experiments on both proteins demonstrated that in the excess of certain metal ions the PG + CA form exhibited the highest catalytic activity ever measured for any CA isozyme. Investigations on the oligomerization and stability of the enzymes revealed that both recombinant proteins form dimers that are stabilized by intermolecular disulfide bond(s). Mass spectrometry experiments showed that CA IX contains an intramolecular disulfide bridge (Cys119-Cys299) and a unique N-linked glycosylation site (Asn309) that bears high mannose-type glycan structures. Parallel experiments on a recombinant protein obtained by a mammalian cell expression system demonstrated the occurrence of an additional O-linked glycosylation site (Thr78) and characterized the nature of the oligosaccharide structures. This study provides novel information on the biochemical properties of CA IX and may help characterize the various cellular and pathophysiological processes in which this unique enzyme is involved.
- Published
- 2008
49. Modification of carbonic anhydrase II with acetaldehyde, the first metabolite of ethanol, leads to decreased enzyme activity
- Author
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Pirjo Vainiotalo, Janne Jänis, Jarkko Valjakka, Claudiu T. Supuran, Abdul Waheed, Sari Isoniemi, Daniela Vullo, Fatemeh Bootorabi, Onni Niemelä, William S. Sly, and Seppo Parkkila
- Subjects
Spectrometry, Mass, Electrospray Ionization ,Metabolite ,Carbonic anhydrase II ,Lysine ,lcsh:Animal biochemistry ,Acetaldehyde ,Biochemistry ,Carbonic Anhydrase II ,lcsh:Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry, Carbonic Anhydrase II ,chemistry/metabolism, Electrophoresis ,Polyacrylamide Gel, Ethanol ,metabolism, Humans, Isoelectric Focusing, Kinetics, Spectrometry ,Mass ,Electrospray Ionization ,Carbonic anhydrase ,Humans ,lcsh:QD415-436 ,Molecular Biology ,lcsh:QP501-801 ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Ethanol ,biology ,Chemistry ,Kinetics ,Enzyme ,biology.protein ,Electrophoresis, Polyacrylamide Gel ,Target protein ,Isoelectric Focusing ,030217 neurology & neurosurgery ,Research Article - Abstract
Background Acetaldehyde, the first metabolite of ethanol, can generate covalent modifications of proteins and cellular constituents. However, functional consequences of such modification remain poorly defined. In the present study, we examined acetaldehyde reaction with human carbonic anhydrase (CA) isozyme II, which has several features that make it a suitable target protein: It is widely expressed, its enzymatic activity can be monitored, its structural and catalytic properties are known, and it contains 24 lysine residues, which are accessible sites for aldehyde reaction. Results Acetaldehyde treatment in the absence and presence of a reducing agent (NaBH3(CN)) caused shifts in the pI values of CA II. SDS-PAGE indicated a shift toward a slightly higher molecular mass. High-resolution mass spectra of CA II, measured with and without NaBH3(CN), indicated the presence of an unmodified protein, as expected. Mass spectra of CA II treated with acetaldehyde revealed a modified protein form (+26 Da), consistent with a "Schiff base" formation between acetaldehyde and one of the primary NH2 groups (e.g., in lysine side chain) in the protein structure. This reaction was highly specific, given the relative abundance of over 90% of the modified protein. In reducing conditions, each CA II molecule had reacted with 9–19 (14 on average) acetaldehyde molecules (+28 Da), consistent with further reduction of the "Schiff bases" to substituted amines (N-ethyllysine residues). The acetaldehyde-modified protein showed decreased CA enzymatic activity. Conclusion The acetaldehyde-derived modifications in CA II molecule may have physiological consequences in alcoholic patients.
- Published
- 2008
50. Detailed nature of tire pyrolysis oil blended with light cycle oil and its hydroprocessed products using a NiW/HY catalyst
- Author
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Timo Kekäläinen, Alazne Gutiérrez, José M. Arandes, Roberto Palos, Janne Jänis, Frank Duodu, and Pedro Castaño
- Subjects
Photoperiod ,020209 energy ,Library science ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Catalysis ,Gas Chromatography-Mass Spectrometry ,Political science ,Ft icr ms ,0202 electrical engineering, electronic engineering, information engineering ,media_common.cataloged_instance ,Christian ministry ,European union ,Waste Management and Disposal ,Gasoline ,Pyrolysis ,0105 earth and related environmental sciences ,media_common - Abstract
The pyrolysis of scrap tires is a very attractive strategy to valorize chemically these end-of-life wastes. The products of this step and any additional one, such as hydrotreating, are relatively complex in nature entangling the understanding and limiting the viability. In this work, we have investigated in detail the composition of a tire pyrolysis oil blended with light cycle oil (from a refinery) and its hydrotreated products using a bifunctional NiW/HY catalyst at 320-400 °C. We have applied a set of analytical techniques to assess the composition, namely simulated distillation, ICP, GC/FID-PFPD, GC × GC/MS, and APPI FT-ICR/MS. Our results show the strength of our analytical workflow to highlight the compositional similarities of this pyrolysis oil with the standard refinery streams. The main differences arise from the higher boiling point species (originated during the pyrolysis of tires) and relatively high concentration of oxygenates. These effects can be minimized by hydrotreating the feed which effectively removes heteroatomic compounds from the feed while boosting the quantity and quality of gasoline and diesel fractions.
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