307 results on '"Maser E"'
Search Results
52. Carbonyl reduction of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in cytosol of mouse liver and lung
- Author
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Atalla, A. and Maser, E.
- Published
- 1999
- Full Text
- View/download PDF
53. The 14CO2 breath test: facilities and limitations of a rapid and noninvasive method for in vivo evaluation of modified hepatic cytochrome P-450 — a critique
- Author
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Brüch, M., Kling, L., Legrum, W., and Maser, E.
- Abstract
By means of the breath test technique the cascade from O-demethylations to CO
2 was investigated after pretreatment of mice with warfarin, phenobarbital, cobaltous chloride, sodium vanadate and metyrapone. It was the intention to examine the validity of the technique with respect to cytochrome P-450 activity. Therefore three different radioactive labeled substrates, i.e., hydrogen carbonate, formate and xenobiotics, were applied at three different levels of the one-carbon pathway and were utilized to demonstrate possible interference of the modifiers with the sequence from O-demethylation to CO2 .- Published
- 1987
- Full Text
- View/download PDF
54. Induction of Daunorubicin Carbonyl Reducing Enzymes by Daunorubicin in Sensitive and Resistant Pancreas Carcinoma Cells
- Author
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Soldan, M., Netter, K. J., and Maser, E.
- Published
- 1996
- Full Text
- View/download PDF
55. Carbonyl reduction of an anti-insect agent imidazole analogue of metyrapone in soil bacteria, invertebrate and vertebrate species
- Author
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Oppermann, U. C., Nagel, G., Belai, I., Bueld, J. E., Genti-Raimondi, S., Koolman, J., Netter, K. J., and Maser, E.
- Published
- 1998
- Full Text
- View/download PDF
56. Molecular cloning, overexpression, and characterization of steroid-inducible 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase from Comamonas testosteroni. A novel member of the short-chain dehydrogenase/reductase superfamily.
- Author
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Möbus, E and Maser, E
- Abstract
3alpha-Hydroxysteroid dehydrogenase/carbonyl reductase (3alpha-HSD/CR) from Comamonas testosteroni, a bacterium that is able to grow on steroids as the sole carbon source, catalyzes the oxidoreduction at position 3 of a variety of C19-27 steroids and the carbonyl reduction of a variety of nonsteroidal aldehydes and ketones. The gene of this steroid-inducible 3alpha-HSD/CR was cloned by screening a C. testosteroni gene bank with a homologous DNA probe that was obtained by polymerase chain reaction with two degenerative primers based on the N-terminal sequence of the purified enzyme. The 3alpha-HSD/CR gene is 774 base pairs long, and the deduced amino acid sequence comprises 258 residues with a calculated molecular mass of 26.4 kDa. A homology search revealed that amino acid sequences highly conserved in the short-chain dehydrogenase/reductase (SDR) superfamily are present in 3alpha-HSD/CR. Two consensus sequences of the SDR superfamily were found, an N-terminal Gly-X-X-X-Gly-X-Gly cofactor-binding motif and a Tyr-X-X-X-Lys segment (residues 155-159 in the 3alpha-HSD/CR sequence) essential for catalytic activity of SDR proteins. 3alpha-HSD/CR was overexpressed and purified to homogeneity, and its activity was determined for steroid and nonsteroidal carbonyl substrates. These results suggest that inducible 3alpha-HSD/CR from C. testosteroni is a novel member of the SDR superfamily.
- Published
- 1998
57. Contribution of aldo-keto reductases to the metabolism of the novel anticancer drug oracin in man
- Author
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Wsol, V., Barbora Szotáková, Skalova, L., and Maser, E.
58. Stereospecific carbonyl reduction of the anticancer drug oracin by 11 beta-hydroxysteroid dehydrogenase/carbonyl reductase
- Author
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Maser, E., Barbora Szotáková, and Wsol, V.
59. Cytostatic drug resistance. Role of phase-I daunorubicin metabolism in cancer cells
- Author
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Soldan M, Ax W, Plebuch M, Lutz Koch, and Maser E
- Subjects
Alcohol Oxidoreductases ,Antibiotics, Antineoplastic ,Aldehyde Reductase ,Drug Resistance, Neoplasm ,Stomach Neoplasms ,Neoplasms ,Daunorubicin ,Aldo-Keto Reductases ,Tumor Cells, Cultured ,Humans ,Transfection
60. 16th Carbonyl Metabolism Meeting: from enzymology to genomics
- Author
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Maser Edmund
- Subjects
Carbonyl metabolism ,Alcohol dehydrogenase (ADH) ,Aldehyde dehydrogenase (ALDH) ,Medium-chain dehydrogenase (MDR) ,Short-chain dehydrogenase/reductase (SDR) ,Aldo-keto reductase (AKR) ,Medicine ,Genetics ,QH426-470 - Abstract
Abstract The 16th International Meeting on the Enzymology and Molecular Biology of Carbonyl Metabolism, Castle of Ploen (Schleswig-Holstein, Germany), July 10–15, 2012, covered all aspects of NAD(P)-dependent oxido-reductases that are involved in the general metabolism of xenobiotic and physiological carbonyl compounds. Starting 30 years ago with enzyme purification, structure elucidation and enzyme kinetics, the Carbonyl Society members have meanwhile established internationally recognized enzyme nomenclature systems and now consider aspects of enzyme genomics and enzyme evolution along with their roles in diseases. The 16th international meeting included lectures from international speakers from all over the world.
- Published
- 2012
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61. Ontogenic pattern of carbonyl reductase activity of 11{beta}-hydroxysteroid dehydrogenase in mouse liver and kidney
- Author
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Freibertshauser, J., Maser, E., and Mangoura, S. A.
- Subjects
ENZYME activation ,CARBONYL reductase - Published
- 1994
62. The purification of 11 -hydroxysteroid dehydrogenase from mouse liver microsomes
- Author
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Maser, E. and Bannenberg, G.
- Published
- 1994
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63. Xenobiotic carbonyl reduction and physiological steroid oxidoreduction. The pluripotency of several hydroxysteroid dehydrogenases
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Maser, E.
- Published
- 1995
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64. Homologies between enzymes involved in steroid and xenobiotic carbonyl reduction in vertebrates, invertebrates and procaryonts
- Author
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Oppermann, U. C. T., Maser, E., Hermans, J. J. R., and Koolman, J.
- Published
- 1992
- Full Text
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65. 11 -Hydroxysteroid dehydrogenase mediates reductive metabolism of xenobiotic carbonyl compounds
- Author
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Maser, E. and Bannenberg, G.
- Published
- 1994
- Full Text
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66. Characterization of carbonyl reducing activity in continuous cell lines of human and rodent origin
- Author
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Gebel, T. and Maser, E.
- Published
- 1992
- Full Text
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67. Strukturelle und immunpharmakologische Untersuchungen zu Arabinogalactan-Proteinen und einem Arabinan aus Echinacea sp
- Author
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Thude, Sebastian, Blaschek, W., and Maser, E.
- Subjects
Echinacea, Arabinogalactan-Protein, Yariv, Immunmodulation, Durchflusszytometrie, Arabinan, Glykoprotein, Polysaccharid ,Abschlussarbeit ,Polysaccharid ,Yariv ,Faculty of Mathematics and Natural Sciences ,Arabinan ,Echinacea ,Glykoprotein ,doctoral thesis ,Arabinogalactan-Protein ,Durchflusszytometrie ,ddc:610 ,Mathematisch-Naturwissenschaftliche Fakultät ,ddc:6XX ,Immunmodulation - Abstract
Arzneimittel mit Zubereitungen aus Echinacea sp. werden als pflanzliche Immunstimulanzien eingesetzt. Dabei kommen niedermolekulare Alkylamide und Cichoriensäure, aber auch hochmolekulare Glykoproteine und Polysaccharide als Wirkprinzipien in Frage. Aus den Wurzeln von Echinacea pallida wurden ein hochmolekulares Glykoprotein vom Typ der Arabinogalactan-Protein (AGP) und ein Polysaccharid vom Typ der Arabinane isoliert und strukturell charakterisiert. Beide zeigen immunmodulatorische Eigenschaften, besonders das AGP. So steigerten die Substanzen in einem in vitro Mausmdodell die Milzzellproliferation, Cytokinfreisetzungen sowie NO- und IgM-Freisetzung. Einem AGP aus dem Presssaft von Echinacea purpurea konnte mit Hilfe von Antikörpern durchflusszytometrisch nachgewiesen werden, dass es konzentrationsabhängig an die Oberfläche von humanen Leukozyten bindet.
- Published
- 2005
68. How contaminated is flatfish living near World Wars' munition dumping sites with energetic compounds?
- Author
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Maser E, Buenning TH, and Strehse JS
- Subjects
- Animals, Weapons, Seawater chemistry, Muscles metabolism, Geologic Sediments chemistry, Flatfishes metabolism, Environmental Monitoring, Water Pollution, Chemical statistics & numerical data, Water Pollutants, Chemical analysis, Water Pollutants, Chemical metabolism
- Abstract
Seas worldwide are threatened by an emerging source of pollution as millions of tons of warfare materials were dumped after the World Wars. As their metal shells are progressively corroding, energetic compounds (EC) leak out and distribute in the marine environment. EC are taken up by aquatic organisms and pose a threat to both the marine ecosphere and the human seafood consumer because of their toxicity and potential carcinogenicity. Here, sediment samples and fish from different locations in the German North Sea of Lower Saxony were examined to determine whether EC transfer to fish living close to munition dumping areas. EC were found in sediments with a maximum concentration of 1.5 ng/kg. All analyzed fish muscle tissues/fillets and bile samples were positive for EC detection. In bile, the max. EC concentrations ranged between 0.25 and 1.25 ng/mL. Interestingly, while detected TNT metabolites in the muscle tissues were in concentrations of max. 1 ng/g (dry weight), TNT itself was found in concentrations of up to 4 ng/g (dry weight). As we found considerable higher amounts of non-metabolized TNT in the fish muscle, rather than TNT metabolites, we conclude an additional absorption route of EC into fish other than per diet. This is the first study to detect EC in the edible parts of fish caught randomly in the North Sea., (© 2024. The Author(s).)
- Published
- 2024
- Full Text
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69. Dietary Chlorella vulgaris supplementation modulates health, microbiota and the response to oxidative stress of Atlantic salmon.
- Author
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Mueller J, van Muilekom DR, Ehlers J, Suhr M, Hornburg SC, Bang C, Wilkes M, Schultheiß T, Maser E, Rebl A, Goldammer T, Seibel H, and Schulz C
- Subjects
- Animals, Gastrointestinal Microbiome drug effects, Aquaculture methods, Microbiota drug effects, Salmo salar microbiology, Salmo salar metabolism, Chlorella vulgaris metabolism, Dietary Supplements, Oxidative Stress drug effects, Animal Feed analysis
- Abstract
Microalgae are emerging as functional feed ingredients in aquaculture due to their immune-stimulating and stress-modulating properties. We investigated the potential of the microalgae Chlorella vulgaris as a feed supplement to improve the health and modulate microbiota and stress responses of Atlantic salmon. Triplicate groups of Atlantic salmon (~ 126 g) were reared in a recirculating aquaculture system (RAS) at 15 °C and received diets supplemented with 2% (CV2) or 14% (CV14) spray-dried C. vulgaris daily, 14% once weekly (CV14w), or a control diet (CD) for 8 weeks. Subsequently, all groups were exposed to an acute one-hour peracetic acid (CH
3 CO3 H; PAA) treatment, a commonly used disinfectant in RAS. While CV14 increased feed conversion (FCR) significantly, feeding the diets CV2 and CV14w improved protein retention efficiency. CV14 significantly modulated beta-diversity in the intestinal digesta and mucosa, but this effect was already visible in fish fed CV2. Feeding CV14 and, to a lesser degree, CV2 increased the relative abundances of Paenarthrobacter and Trichococcus in the digesta and mucosa, which are able to metabolize complex carbohydrates. However, the same diets reduced the abundance of the lactic acid bacteria Lactobacillus and Weissella in the digesta and Floricoccus in the mucosa. Peracetic acid exposure induced systemic stress (increase in plasma glucose and cortisol) and a local immune response in the gill, with the most prominent upregulation of several immune- and stress-regulated genes (clra, cebpb, marco, tnfrsf14, ikba, c1ql2, drtp1) 18 h after exposure in fish fed the control diet. Fish receiving CV14 once a week showed a reduced transcriptional response to PAA exposure. Catalase protein abundance in the liver increased following exposure to PAA, while superoxide dismutase abundance in the gill and liver was increased in response to C. vulgaris inclusion before stress. Overall, the results highlight that a high (14%) inclusion rate of C. vulgaris in feed for Atlantic salmon impairs feed conversion and shifts the intestinal microbiota composition in digesta and mucosa. Weekly feeding of C. vulgaris proves a viable approach in improving protein retention and improving transcriptional resilience towards oxidative stress in increasingly intensive production systems. Thereby this study may motivate future studies on optimizing temporal feeding schedules for health-promoting aquafeeds., (© 2024. The Author(s).)- Published
- 2024
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70. Metabolic activation of 2,4,6-trinitrotoluene; a case for ROS-induced cell damage.
- Author
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Adomako-Bonsu AG, Jacobsen J, and Maser E
- Subjects
- Humans, Activation, Metabolic, Animals, Explosive Agents metabolism, Explosive Agents toxicity, Oxidation-Reduction, Trinitrotoluene metabolism, Trinitrotoluene toxicity, Reactive Oxygen Species metabolism, Oxidative Stress drug effects
- Abstract
The explosive compound 2,4,6-trinitrotoluene (TNT) is well known as a major component of munitions. In addition to its potential carcinogenicity and mutagenicity in humans, recent reports have highlighted TNT toxicities in diverse organisms due to its occurrence in the environment. These toxic effects have been linked to the intracellular metabolism of TNT, which is generally characterised by redox cycling and the generation of noxious reactive molecules. The reactive intermediates formed, such as nitroso and hydroxylamine compounds, also interact with oxygen molecules and cellular components to cause macromolecular damage and oxidative stress. The current review aims to highlight the crucial role of TNT metabolism in mediating TNT toxicity, via increased generation of reactive oxygen species. Cellular proliferation of reactive species results in depletion of cellular antioxidant enzymes, DNA and protein adduct formation, and oxidative stress. While TNT toxicity is well known, its ability to induce oxidative stress, resulting from its reductive activation, suggests that some of its toxic effects may be caused by its reactive metabolites. Hence, further research on TNT metabolism is imperative to elucidate TNT-induced toxicities., Competing Interests: Declaration of competing interest I, as the corresponding author, declare on behalf of all the authors of the submission, that there is not any financial interest or personal relationship with other people or organizations that could inappropriately influence this work., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
71. The mechanism of anthracene degradation by tryptophan -2,3-dioxygenase (T23D) in Comamonas testosteroni.
- Author
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Xu M, Yang X, Zhang J, Liu D, Zhang C, Wu M, Musazade E, Maser E, Xiong G, and Guo L
- Subjects
- Tryptophan, Anthracenes, Comamonas testosteroni genetics, Dioxygenases metabolism, Polycyclic Aromatic Hydrocarbons metabolism
- Abstract
It is well known that anthracene is a persistent organic pollutant. Among the four natural polycyclic aromatic hydrocarbons (PAHs) degrading strains, Comamonas testosterone (CT1) was selected as the strain with the highest degradation efficiency. In the present study, prokaryotic transcriptome analysis of CT1 revealed an increase in a gene that encodes tryptophane-2,3-dioxygenase (T23D) in the anthracene and erythromycin groups compared to CK. Compared to the wild-type CT1 strain, anthracene degradation by the CtT23D knockout mutant (CT-M1) was significantly reduced. Compared to Escherichia coli (DH5α), CtT23D transformed DH5α (EC-M1) had a higher degradation efficiency for anthracene. The recombinant protein rT23D oxidized tryptophan at pH 7.0 and 37 °C with an enzyme activity of 2.42 ± 0.06 μmol min
-1 ·mg-1 protein. In addition, gas chromatography-mass (GC-MS) analysis of anthracene degradation by EC-M1 and the purified rT23D revealed that 2-methyl-1-benzofuran-3-carbaldehyde is an anthracene metabolite, suggesting that it is a new pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
72. Salinity change evokes stress and immune responses in Atlantic salmon with microalgae showing limited potential for dietary mitigation.
- Author
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van Muilekom DR, Mueller J, Lindemeyer J, Schultheiß T, Maser E, Seibel H, Rebl A, Schulz C, and Goldammer T
- Abstract
Smoltification was found to impact both immune and stress responses of farmed Atlantic salmon ( Salmo salar ), but little is known about how salinity change affects salmon months after completed smoltification. Here, we examined (1) the effect of salinity change from brackish water to seawater on the stress and immune responses in Atlantic salmon and (2) evaluated if functional diets enriched with microalgae can mitigate stress- and immune-related changes. Groups of Atlantic salmon were fed for 8 weeks with different microalgae-enriched diets in brackish water and were then transferred into seawater. Samples of the head kidney, gill, liver and plasma were taken before seawater transfer (SWT), 20 h after SWT, and 2 weeks after SWT for gene-expression analysis, plasma biochemistry and protein quantification. The salmon showed full osmoregulatory ability upon transfer to seawater reflected by high nkaα1b levels in the gill and tight plasma ion regulation. In the gill, one-third of 44 investigated genes were reduced at either 20 h or 2 weeks in seawater, including genes involved in cytokine signaling ( il1b ) and antiviral defense ( isg15, rsad2, ifit5 ). In contrast, an acute response after 20 h in SW was apparent in the head kidney reflected by increased plasma stress indicators and induced expression of genes involved in acute-phase response ( drtp1 ), antimicrobial defense ( camp ) and stress response ( hspa5 ). However, after 2 weeks in seawater, the expression of antiviral genes ( isg15, rsad2, znfx1 ) was reduced in the head kidney. Few genes ( camp, clra, c1ql2 ) in the gill were downregulated by a diet with 8% inclusion of Athrospira platensis . The results of the present study indicate that salinity change months after smoltification evokes molecular stress- and immune responses in Atlantic salmon. However, microalgae-enriched functional diets seem to have only limited potential to mitigate the related changes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 van Muilekom, Mueller, Lindemeyer, Schultheiß, Maser, Seibel, Rebl, Schulz and Goldammer.)
- Published
- 2024
- Full Text
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73. Ecotoxicological Risk of World War Relic Munitions in the Sea after Low- and High-Order Blast-in-Place Operations.
- Author
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Maser E, Andresen KJ, Bünning TH, Clausen OR, Wichert U, and Strehse JS
- Subjects
- Humans, Tandem Mass Spectrometry, Chromatography, Liquid, Oceans and Seas, Water, Explosions, Water Pollutants, Chemical toxicity
- Abstract
Submerged munitions from World War I and II are threatening human activities in the oceans, including fisheries and shipping or the construction of pipelines and offshore facilities. To avoid unforeseen explosions, remotely controlled "blast-in-place" (BiP) operations are a common practice worldwide. However, after underwater BiP detonations, the toxic and carcinogenic energetic compounds (ECs) will not completely combust but rather distribute within the marine ecosphere. To shed light on this question, two comparable World War II mines in Denmark's Sejerø Bay (Baltic Sea) were blown up by either low-order or high-order BiP operations by the Royal Danish Navy. Water and sediment samples were taken before and immediately after the respective BiP operation and analyzed for the presence of ECs with sensitive GC-MS/MS and LC-MS/MS technology. EC concentrations increased after high-order BiP detonations up to 353 ng/L and 175 μg/kg in water and sediment, respectively, while low-order BiP detonations resulted in EC water and sediment concentrations up to 1,000,000 ng/L (1 mg/L) and >10,000,000 μg/kg (>10 g/kg), respectively. Our studies provide unequivocal evidence that BiP operations in general lead to a significant increase of contamination of the marine environment and ecotoxicological risk with toxic ECs. Moreover, as compared to high-order BiP detonations, low-order BiP detonations resulted in a several 1000-fold higher burden on the marine environment.
- Published
- 2023
- Full Text
- View/download PDF
74. Influence of Early Life Factors, including breast milk Composition, on the Microbiome of Infants Born to Mothers with and without Inflammatory Bowel Disease.
- Author
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Sabino J, Tarassishin L, Eisele C, Hawkins K, Barré A, Nair N, Rendon A, Debebe A, Picker M, Agrawal M, Stone J, George J, Legnani P, Maser E, Chen CL, Thjømøe A, Mørk E, Dubinsky M, Hu J, Colombel JF, Peter I, and Torres J
- Subjects
- Infant, Female, Humans, Pregnancy, Milk, Human chemistry, Prospective Studies, RNA, Ribosomal, 16S genetics, Proteomics, Feces chemistry, Leukocyte L1 Antigen Complex analysis, Mothers, Microbiota, Inflammatory Bowel Diseases metabolism
- Abstract
Background and Aims: Herein we analysed the influence of early life factors, including breast milk composition, on the development of the intestinal microbiota of infants born to mothers with and without IBD., Methods: The MECONIUM [Exploring MEChanisms Of disease traNsmission In Utero through the Microbiome] study is a prospective cohort study consisting of pregnant women with or without IBD and their infants. Longitudinal stool samples were collected from babies and analysed using 16s rRNA sequencing and faecal calprotectin. Breast milk proteomics was profiled using Olink inflammation panel., Results: We analysed gut microbiota of 1034 faecal samples from 294 infants [80 born to mothers with and 214 to mothers without IBD]. Alpha diversity was driven by maternal IBD status and time point. The major influencers of the overall composition of the microbiota were mode of delivery, feeding, and maternal IBD status. Specific taxa were associated with these exposures, and maternal IBD was associated with a reduction in Bifidobacterium. In 312 breast milk samples [91 from mothers with IBD], mothers with IBD displayed lower abundance of proteins involved in immune regulation, such as thymic stromal lymphopoietin, interleukin-12 subunit beta, tumour necrosis factor-beta, and C-C motif chemokine 20, as compared with control mothers [adjusted p = 0.0016, 0.049, 0.049, and 0.049, respectively], with negative correlations with baby´s calprotectin, and microbiome at different time points., Conclusion: Maternal IBD diagnosis influences microbiota in their offspring during early life. The proteomic profile of breast milk of women with IBD differs from that of women without IBD, with distinct time-dependent associations with baby's gut microbiome and feacal calprotectin., (© The Author(s) 2023. Published by Oxford University Press on behalf of European Crohn’s and Colitis Organisation. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2023
- Full Text
- View/download PDF
75. Long-Term Trends for Blue Mussels from the German Environmental Specimen Bank Show First Evidence of Munition Contaminants Uptake.
- Author
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Strehse JS, Bünning TH, Koschorreck J, Künitzer A, and Maser E
- Abstract
Submerged munitions are present in marine waters across the globe. They contain energetic compounds (ECs), such as TNT and metabolites thereof, which are considered carcinogenic, exhibit toxic effects in marine organisms, and may affect human health. The aim of this study was to investigate the occurrence of ECs and their trends in blue mussels from the annual collections of the German Environmental Specimen Bank sampled over the last 30 years at three different locations along the coastline of the Baltic and North Sea. Samples were analyzed by GC-MS/MS for 1,3-dinitrobenzene (1,3-DNB), 2,4-dinitrotoluene (2,4-DNT), 2,4,6-trinitrotoluene (TNT), 2-amino-4,6-dinitrotoluene (2-ADNT), and 4-amino-2,6-dinitrotoluene (4-ADNT). The first signals indicating trace levels of 1,3-DNB were observed in samples from 1999 and 2000. ECs were also found below the limit of detection (LoD) in subsequent years. From 2012 onwards, signals just above the LoD were detected. The highest signal intensities of 2-ADNT and 4-ADNT, just below the LoQ (0.14 ng/g d.w. and 0.17 ng/g d.w., respectively), were measured in 2019 and 2020. This study clearly shows that corroding submerged munitions are gradually releasing ECs into the waters that can be detected in randomly sampled blue mussels, even though the concentrations measured are still in the non-quantifiable trace range.
- Published
- 2023
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76. Critical Role of Monooxygenase in Biodegradation of 2,4,6-Trinitrotoluene by Buttiauxella sp. S19-1.
- Author
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Xu M, He L, Sun P, Wu M, Cui X, Liu D, Adomako-Bonsu AG, Geng M, Xiong G, Guo L, and Maser E
- Subjects
- Biodegradation, Environmental, Mixed Function Oxygenases, Escherichia coli metabolism, Trinitrotoluene metabolism
- Abstract
2,4,6-Trinitrotoluene (TNT) is an aromatic pollutant that is difficult to be degraded in the natural environment. The screening of efficient degrading bacteria for bioremediation of TNT has received much attention from scholars. In this paper, transcriptome analysis of the efficient degrading bacterium Buttiauxella sp. S19-1 revealed that the monooxygenase gene ( BuMO ) was significantly up-regulated during TNT degradation. S-Δ MO (absence of BuMO gene in S19-1 mutant) degraded TNT 1.66-fold less efficiently than strain S19-1 (from 71.2% to 42.9%), and E- MO mutant ( Escherichia coli BuMO -expressing strain) increased the efficiency of TNT degradation 1.33-fold (from 52.1% to 69.5%) for 9 h at 180 rpm at 27 °C in LB medium with 1.4 µg·mL
-1 TNT. We predicted the structure of BuMO and purified recombinant BuMO (rBuMO). Its specific activity was 1.81 µmol·min-1 ·mg-1 protein at pH 7.5 and 35 °C. The results of gas chromatography mass spectrometry (GC-MS) analysis indicated that 4-amino-2,6-dinitrotoluene (ADNT) is a metabolite of TNT biodegradation. We speculate that MO is involved in catalysis in the bacterial degradation pathway of TNT in TNT-polluted environment.- Published
- 2023
- Full Text
- View/download PDF
77. Warship wrecks and their munition cargos as a threat to the marine environment and humans: The V 1302 "JOHN MAHN" from World War II.
- Author
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Maser E, Bünning TH, Brenner M, Van Haelst S, De Rijcke M, Müller P, Wichert U, and Strehse JS
- Subjects
- Animals, Humans, Ecosystem, World War II, Energy-Generating Resources, Tandem Mass Spectrometry, Wind, Fishes, Water analysis, Environmental Monitoring, Water Pollutants, Chemical analysis
- Abstract
In addition to endangering sea traffic, cable routes, and wind farms, sunken warship wrecks with dangerous cargo, fuel, or munitions on board may emerge as point sources for environmental damage. Energetic compounds such as TNT (which could leak from these munitions) are known for their toxicity, mutagenicity, and carcinogenicity. These compounds may cause potential adverse effects on marine life via contamination of the marine ecosystem, and their entry into the marine and human food chain could directly affect human health. To ascertain the impending danger of an environmental catastrophe posed by sunken warships, the North Sea Wrecks (NSW) project (funded by the Interreg North Sea Region Program) was launched in 2018. Based on historical data (derived from military archives) including the calculated amount of munitions still on board, its known location and accessibility, the German World War II ship "Vorpostenboot 1302" (former civilian name - "JOHN MAHN") was selected as a case study to investigate the leakage and distribution of toxic explosives in the marine environment. The wreck site and surrounding areas were mapped in great detail by scientific divers and a multibeam echosounder. Water and sediment samples were taken in a cross-shaped pattern around the wreck. To assess a possible entry into the marine food chain, caged mussels were exposed at the wreck, and wild fish (pouting), a sedentary species that stays locally at the wreck, were caught. All samples were analyzed for the presence of TNT and derivatives thereof by GC-MS/MS analysis. As a result, we could provide evidence that sunken warship wrecks emerge as a point source of contamination with nitroaromatic energetic compounds leaking from corroding munitions cargo still on board. Not only did we find these explosive substances in bottom water and sediment samples around the wreck, but also in the caged mussels as well as in wild fish living at the wreck. Fortunately so far, the concentrations found in mussel meat and fish filet were only in the one-digit ng per gram range thus indicating no current concern for the human seafood consumer. However, in the future the situation may worsen as the corrosion continues. From our study, it is proposed that wrecks should not only be ranked according to critical infrastructure and human activities at sea, but also to the threats they pose to the environment and the human seafood consumer., Competing Interests: Declaration of competing interest I, as the corresponding author, declare on behalf of all the authors of the submission, that there is not any financial interest or personal relationship with other people or organizations that could inappropriately influence this work., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
78. Improved Smoking Cessation Rates in a Pharmacist-Led Program Embedded in an Inflammatory Bowel Disease Specialty Medical Home.
- Author
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Tse SS, Sands BE, Keefer L, Cohen BL, Maser E, Ungaro RC, Marion JF, Colombel JF, Itzkowitz SH, Gelman J, and Dubinsky MC
- Subjects
- Humans, Pharmacists, Prospective Studies, Patient-Centered Care, Smoking Cessation methods, Crohn Disease, Biological Products
- Abstract
Background: Cigarette smoking is associated with disease progression, poor outcomes, and increased biologic use in Crohn's Disease (CD). In this prospective study, we describe the structure and results of a pharmacist-driven smoking cessation program in an Inflammatory Bowel Disease (IBD) Specialty Medical Home., Methods: One pharmacist designed and implemented a collaborative drug therapy management (CDTM) program, which allowed the pharmacist to initiate and modify smoking cessation aids, monitor medication safety and efficacy, and provide behavioral counseling. Crohn's Disease patients who were current smokers and referred to the program were analyzed. Clinical and demographic data, disease activity, and smoking history were collected. The primary outcome was the proportion of patients in the enrolled group and the declined group who quit smoking at least once during the follow-up period. Secondary outcomes include demographic and clinical differences between enrolled and declined patients, and enrolled quitters and non-quitters., Results: Thirty-two patients were referred to the program and 19 participated. Over a median follow-up period of 305 [264-499] days, 42% (8/19) of enrolled patients quit smoking at least once. Fifteen percent (2/13) of declined patients quit smoking. Patients who continued to smoke had more instances of loss of response to a biologic, need to start a new biologic, or escalation of biologic therapy. The CDTM pharmacist was able to provide all necessary clinical services for smokers enrolled in the program., Conclusions: A pharmacist-led smoking cessation program in a specialty medical home is feasible. It may result in successful quit attempts and may optimize IBD medication use.
- Published
- 2022
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79. Energetic Compounds in the Trophic Chain—A Pilot Study Examining the Exposure Risk of Common Eiders (Somateria mollissima) to TNT, Its Metabolites, and By-Products
- Author
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Schick LA, Strehse JS, Bünning TH, Maser E, and Siebert U
- Abstract
The Baltic and North Seas still contain large amounts of dumped munitions from both World Wars. The exposure of the munition shells to the seawater causes corrosion, which leads to the disintegration of shells and a leakage of energetic compounds, including the highly toxic 2,4,6-trinitrotoluene (TNT), and consequently threatening the marine environment. To evaluate the risk of accumulation of energetic compounds from conventional munitions in the marine food chain, we analyzed the presence of TNT and its metabolites 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) as well as their byproducts 1,3-dinitrobenzene (1,3-DNB) and 2,4-dinitrotoluene (2,4-DNT) in different tissues (including muscle, liver, kidney, brain, and bile) from 25 Common Eiders ( Somateria mollissima ) from the Danish Baltic Sea. Tissues were prepared according to approved protocols, followed by GC-MS/MS analysis. None of the aforementioned energetic compounds were detected in any of the samples. This pilot study is one of the first analyzing the presence of explosive chemicals in tissues from a free-ranging predatory species. This study highlights the need for continuous monitoring at different levels of the trophic chain to increase our knowledge on the distribution and possible accumulation of energetic compounds in the marine environment in order to provide reliable data for decision-making tools and risk assessments.
- Published
- 2022
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80. Carbonyl reduction of 4-oxonon-2-enal (4-ONE) by Sniffer from D. magna and D.pulex.
- Author
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Strehse JS, Hoffmann D, Protopapas N, Martin HJ, and Maser E
- Subjects
- Animals, Alcohol Oxidoreductases metabolism, Alcohol Oxidoreductases genetics, Recombinant Proteins metabolism, Recombinant Proteins chemistry, Chromatography, High Pressure Liquid, Daphnia metabolism, Aldehydes metabolism, Aldehydes chemistry, Oxidation-Reduction
- Abstract
The α, β-unsaturated aldehydes 4-oxonon-2-enal (4ONE) and 4-hydroxynon-2-enal (4HNE) are products of unsaturated fatty acids and ROS, and can be formed in lipid-rich tissues such as neurons. As strong electrophiles, both compounds react with DNA and proteins, and are capable of inactivating enzymes. However, both the human carbonyl reductase and the carbonyl reductase Drosophila melanogaster Sniffer are known to reduce 4ONE, a major lipid peroxidation product, to a less or non-toxic form. In this study, products formed during carbonyl reduction of 4ONE and 4HNE by recombinant Sniffer proteins from Daphnia magna and Daphnia pulex were investigated. A high-performance liquid chromatography analysis showed that Sniffer from D. magna converted 35.6% of 4ONE to 11.9% HNO and 23.7% 4HNE, while D. pulex converted 34.5% of this substrate to 14.8% HNO and 19.7% 4HNE. Thus, 4HNE is the main product formed from the sniffer-mediated reduction of 4ONE. The kinetic parameters obtained from the reduction of 4ONE were K
m = 13.9 ± 2.1 μM, kcat = 1.53 s-1 , kcat /km = 0.11 s-1 μM-1 for D. magna Sniffer and Km = 29.2 ± 4.3 μM, kcat = 0.64 s-1 , kcat /km = 0.02 s-1 μM-1 for D. pulex Sniffer. These results demonstrate that Sniffer from D. magna and D. pulex are important enzymes involved in the carbonyl reductive biotransformation of 4ONE, a cytotoxic lipid peroxidation product. Noteworthy, the catalytic properties of both Daphnia Sniffer enzymes reflect previous findings with Sniffer from Drosophila melanogaster., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
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81. Inhibition of human carbonyl reducing enzymes by plant anthrone and anthraquinone derivatives.
- Author
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Westermann M, Adomako-Bonsu AG, Thiele S, Çiçek SS, Martin HJ, and Maser E
- Subjects
- Humans, Enzyme Inhibitors pharmacology, Enzyme Inhibitors chemistry, Aldehyde Reductase antagonists & inhibitors, Aldehyde Reductase metabolism, Aldo-Keto Reductase Family 1 Member C3 antagonists & inhibitors, Aldo-Keto Reductase Family 1 Member C3 metabolism, 3-Hydroxysteroid Dehydrogenases antagonists & inhibitors, 3-Hydroxysteroid Dehydrogenases metabolism, Anthracenes pharmacology, Anthracenes chemistry, Hydroxyprostaglandin Dehydrogenases antagonists & inhibitors, Hydroxyprostaglandin Dehydrogenases metabolism, Escherichia coli enzymology, Alcohol Oxidoreductases antagonists & inhibitors, Alcohol Oxidoreductases metabolism, Alcohol Oxidoreductases chemistry, Recombinant Proteins metabolism, Recombinant Proteins chemistry, Kinetics, Carbonyl Reductase (NADPH) metabolism, Carbonyl Reductase (NADPH) antagonists & inhibitors, Plants chemistry, Short Chain Dehydrogenase-Reductases metabolism, Short Chain Dehydrogenase-Reductases chemistry, Short Chain Dehydrogenase-Reductases antagonists & inhibitors, 20-Hydroxysteroid Dehydrogenases, Anthraquinones chemistry, Anthraquinones pharmacology, Anthraquinones metabolism, Aldo-Keto Reductases antagonists & inhibitors, Aldo-Keto Reductases metabolism, Aldo-Keto Reductases chemistry, Aldo-Keto Reductases genetics
- Abstract
Members of the aldo-keto reductase and short-chain dehydrogenase/reductase enzyme superfamilies catalyze the conversion of a wide range of substrates, including carbohydrates, lipids, and steroids. These enzymes also participate in the transformation of xenobiotics, inactivation of the cytostatics doxo- and daunorubicin, and play a role in the development of cancer. Therefore, inhibitors of such enzymes may improve therapeutic outcomes. Plant-derived compounds such as anthraquinones have been used for medicinal purposes for several centuries. In the current study, the inhibitory potential of selected anthrone and anthraquinone derivatives (from plants) was tested on six recombinant human carbonyl reducing enzymes (AKR1B1, AKR1B10, AKR1C3, AKR7A2, AKR7A3, CBR1) isolated from an Escherichia coli expression system. Overall, the least inhibition was observed with the anthrone derivative aloin, while IC
50 values obtained with the anthraquinone derivatives (frangula emodin, aloe emodin, frangulin A, and frangulin B) and the aldo-keto reductase AKR1B10 were in the low micromolar range (3.5-16.6 μM). AKR1B1 inhibition was significantly weaker in comparison with AKR1B10 inhibition (IC50 values > 50 μM). The strongest inhibition was observed with the short-chain dehydrogenase/reductase CBR1. AKR7A2, AKR7A3, and AKR1C3 were not, or less inhibited by inhibitor concentrations of up to 50 μM. Analysis of the kinetic data suggests noncompetitive or uncompetitive inhibition mechanisms. The new inhibitors described here may serve as lead structures for the development of future drugs., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
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82. Induction of carbonyl reductase 1 (CR1) gene expression in Daphnia magna by TNT, but not its key metabolites 2-ADNT and 4-ADNT.
- Author
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Jacobsen J, Adomako-Bonsu AG, and Maser E
- Subjects
- Aniline Compounds pharmacology, Animals, Biomarkers metabolism, Carbonyl Reductase (NADPH) genetics, Carbonyl Reductase (NADPH) metabolism, Daphnia drug effects, Trinitrotoluene pharmacology, Up-Regulation drug effects, Water Pollutants, Chemical pharmacology
- Abstract
2,4,6-trinitrotoluene (TNT) is a known source of reactive oxygen species (ROS), which cause oxidative stress in aquatic ecosystems. Carbonyl reductases (CRs) are one of several possible defense mechanisms induced against ROS products, especially those that result in the 'so-called' carbonyl stress. Daphnia magna, a freshwater organism living in stagnant freshwater bodies, expresses four copies of the CR gene (Dma_CR1, Dma_CR2, Dma_CR3 and Dma_CR4). In this study, induction of all four copies of Dma_CR by 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT), was investigated. Reverse transcription polymerase chain reaction (RT-PCR) analysis of treated daphnids revealed up-regulation of Dma_CR1 alone in response to TNT, but not 2-ADNT and 4-ADNT (which are key metabolites of TNT). This concentration- and time-dependent up-regulation in mRNA-expression was observed both in the presence and absence of light, in the same magnitude. Moreover, significant change in mRNA-expression could be observed 8 h after treatment with TNT. In the presence of TNT, the antioxidant N-acetylcysteine (NAc) could not reverse TNT-induced up-regulation of Dma_CR1 mRNA-expression. On the other hand, withdrawal of TNT from the culture medium caused a significant reduction in the TNT-induced mRNA-expression of Dma_CR1 within 24 h. These findings highlight the potential of Dma_CR1 as a biomarker for biomonitoring of TNT levels in freshwater bodies., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2022
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83. Genomic analysis of Gordonia polyisoprenivorans strain R9, a highly effective 17 beta-estradiol- and steroid-degrading bacterium.
- Author
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Liu N, Maser E, and Zhang T
- Subjects
- Actinobacteria classification, Animals, Base Composition, Biodegradation, Environmental, Endocrine Disruptors metabolism, Estrogens metabolism, Genome, Bacterial, Humans, Multigene Family, Phylogeny, Species Specificity, Actinobacteria genetics, Actinobacteria metabolism, Environmental Pollutants metabolism, Estradiol metabolism, Steroids metabolism
- Abstract
The increasing levels of estrogens and pollution by other steroids pose considerable challenges to the environment. In this study, the genome of Gordonia polyisoprenivorans strain R9, one of the most effective 17 beta-estradiol- and steroid-degrading bacteria, was sequenced and annotated. The circular chromosome of G. polyisoprenivorans R9 was 6,033,879 bp in size, with an average GC content of 66.91%. More so, 5213 putative protein-coding sequences, 9 rRNA, 49 tRNA, and 3 sRNA genes were predicted. The core-pan gene evolutionary tree for the genus Gordonia showed that G. polyisoprenivorans R9 is clustered with G. polyisoprenivorans VH2 and G. polyisoprenivorans C, with 93.75% and 93.8% similarity to these two strains, respectively. Altogether, the three G. polyisoprenivorans strains contained 3890 core gene clusters. Strain R9 contained 785 specific gene clusters, while 501 and 474 specific gene clusters were identified in strains VH2 and C, respectively. Furthermore, whole genome analysis revealed the existence of the steroids and estrogens degradation pathway in the core genome of all three G. polyisoprenivorans strains, although the G. polyisoprenivorans R9 genome contained more specific estrogen and steroid degradation genes. In strain R9, 207 ABC transporters, 95 short-chain dehydrogenases (SDRs), 26 monooxygenases, 21 dioxygenases, 7 aromatic ring-hydroxylating dioxygenases, and 3 CoA esters were identified, and these are very important for estrogen and steroid transport, and degradation. The results of this study could enhance our understanding of the role of G. polyisoprenivorans R9 in estradiol and steroid degradation as well as evolution within the G. polyisoprenivorans species., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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84. Machine Learning Predicts the Presence of 2,4,6-Trinitrotoluene in Sediments of a Baltic Sea Munitions Dumpsite Using Microbial Community Compositions.
- Author
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Janßen R, Beck AJ, Werner J, Dellwig O, Alneberg J, Kreikemeyer B, Maser E, Böttcher C, Achterberg EP, Andersson AF, and Labrenz M
- Abstract
Bacteria are ubiquitous and live in complex microbial communities. Due to differences in physiological properties and niche preferences among community members, microbial communities respond in specific ways to environmental drivers, potentially resulting in distinct microbial fingerprints for a given environmental state. As proof of the principle, our goal was to assess the opportunities and limitations of machine learning to detect microbial fingerprints indicating the presence of the munition compound 2,4,6-trinitrotoluene (TNT) in southwestern Baltic Sea sediments. Over 40 environmental variables including grain size distribution, elemental composition, and concentration of munition compounds (mostly at pmol⋅g
-1 levels) from 150 sediments collected at the near-to-shore munition dumpsite Kolberger Heide by the German city of Kiel were combined with 16S rRNA gene amplicon sequencing libraries. Prediction was achieved using Random Forests (RFs); the robustness of predictions was validated using Artificial Neural Networks (ANN). To facilitate machine learning with microbiome data we developed the R package phyloseq2ML. Using the most classification-relevant 25 bacterial genera exclusively, potentially representing a TNT-indicative fingerprint, TNT was predicted correctly with up to 81.5% balanced accuracy. False positive classifications indicated that this approach also has the potential to identify samples where the original TNT contamination was no longer detectable. The fact that TNT presence was not among the main drivers of the microbial community composition demonstrates the sensitivity of the approach. Moreover, environmental variables resulted in poorer prediction rates than using microbial fingerprints. Our results suggest that microbial communities can predict even minor influencing factors in complex environments, demonstrating the potential of this approach for the discovery of contamination events over an integrated period of time. Proven for a distinct environment future studies should assess the ability of this approach for environmental monitoring in general., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Janßen, Beck, Werner, Dellwig, Alneberg, Kreikemeyer, Maser, Böttcher, Achterberg, Andersson and Labrenz.)- Published
- 2021
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85. Degradation of 2,4,6-Trinitrotoluene (TNT): Involvement of Protocatechuate 3,4-Dioxygenase (P34O) in Buttiauxella sp. S19-1.
- Author
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Xu M, Liu D, Sun P, Li Y, Wu M, Liu W, Maser E, Xiong G, and Guo L
- Abstract
Extensive use and disposal of 2,4,6-trinitrotoluene (TNT), a primary constituent of explosives, pollutes the environment and causes severe damage to human health. Complete mineralization of TNT via bacterial degradation has recently gained research interest as an effective method for the restoration of contaminated sites. Here, screening for TNT degradation by six selected bacteria revealed that Buttiauxella sp. S19-1, possesses the strongest degrading ability. Moreover, BuP34O (a gene encoding for protocatechuate 3,4-dioxygenase-P34O, a key enzyme in the β-ketoadipate pathway) was upregulated during TNT degradation. A knockout of BuP34O in S19-1 to generate S-M1 mutant strain caused a marked reduction in TNT degradation efficiency compared to S19-1. Additionally, the EM1 mutant strain ( Escherichia coli DH5α transfected with BuP34O ) showed higher degradation efficiency than DH5α. Gas chromatography mass spectrometry (GC-MS) analysis of TNT degradation by S19-1 revealed 4-amino-2,6-dinitrotolune (ADNT) as the intermediate metabolite of TNT. Furthermore, the recombinant protein P34O (rP34O) expressed the activity of 2.46 µmol/min·mg. Our findings present the first report on the involvement of P34O in bacterial degradation of TNT and its metabolites, suggesting that P34O could catalyze downstream reactions in the TNT degradation pathway. In addition, the TNT-degrading ability of S19-1, a Gram-negative marine-derived bacterium, presents enormous potential for restoration of TNT-contaminated seas.
- Published
- 2021
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86. Correction to: The explosive trinitrotoluene (TNT) induces gene expression of carbonyl reductase in the blue mussel (Mytilus spp.): a new promising biomarker for sea dumped war relicts?
- Author
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Strehse JS, Brenner M, Kisiela M, and Maser E
- Published
- 2021
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87. Correction to: "Don't Blast": blast‑in‑place (BiP) operations of dumped World War munitions in the oceans significantly increase hazards to the environment and the human seafood consumer.
- Author
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Maser E and Strehse JS
- Published
- 2021
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88. Can seafood from marine sites of dumped World War relicts be eaten?
- Author
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Maser E and Strehse JS
- Subjects
- Animals, Environmental Monitoring, Fishes, Seafood, Explosive Agents toxicity, Trinitrotoluene, Water Pollutants, Chemical analysis, Water Pollutants, Chemical toxicity
- Abstract
Since World War I, considerable amounts of warfare materials have been dumped at seas worldwide. After more than 70 years of resting on the seabed, reports suggest that the metal shells of these munitions are corroding, such that explosive chemicals leak out and distribute in the marine environment. Explosives such as TNT (2,4,6-trinitrotoluene) and its derivatives are known for their toxicity and carcinogenicity, thereby posing a threat to the marine environment. Toxicity studies suggest that chemical components of munitions are unlikely to cause acute toxicity to marine organisms. However, there is increasing evidence that they can have sublethal and chronic effects in aquatic biota, especially in organisms that live directly on the sea floor or in subsurface substrates. Moreover, munition-dumping sites could serve as nursery habitats for young biota species, demanding special emphasis on all kinds of developing juvenile marine animals. Unfortunately, these chemicals may also enter the marine food chain and directly affect human health upon consuming contaminated seafood. While uptake and accumulation of toxic munition compounds in marine seafood species such as mussels and fish have already been shown, a reliable risk assessment for the human seafood consumer and the marine ecosphere is lacking and has not been performed until now. In this review, we compile the first data and landmarks for a reliable risk assessment for humans who consume seafood contaminated with munition compounds. We hereby follow the general guidelines for a toxicological risk assessment of food as suggested by authorities.
- Published
- 2021
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89. Exposure to dissolved TNT causes multilevel biological effects in Baltic mussels (Mytilus spp.).
- Author
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Schuster R, Strehse JS, Ahvo A, Turja R, Maser E, Bickmeyer U, Lehtonen KK, and Brenner M
- Subjects
- Animals, Baltic States, Biomarkers, Mytilus, Trinitrotoluene, Water Pollutants, Chemical analysis, Water Pollutants, Chemical toxicity
- Abstract
Baltic mussels (Mytilus spp.) were exposed to the explosive trinitrotoluene (TNT) for 96 h (0.31-10.0 mg/L) and 21 d (0.31-2.5 mg/L). Bioaccumulation of TNT and its degradation products (2- and 4-ADNT) as well as biological effects ranging from the gene and cellular levels to behaviour were investigated. Although no mortality occurred in the concentration range tested, uptake and metabolism of TNT and responses in antioxidant enzymes and histochemical biomarkers were observed already at the lowest concentrations. The characteristic shell closure behaviour of bivalves at trigger concentrations led to complex exposure patterns and non-linear responses to the exposure concentrations. Conclusively, exposure to TNT exerts biomarker reponses in mussels already at 0.31 mg/L while effects are recorded also after a prolonged exposure although no mortality occurs. Finally, more attention should be paid on shell closure of bivalves in exposure studies since it plays a marked role in definining toxicity threshold levels., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2021
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90. A Toolbox for the Determination of Nitroaromatic Explosives in Marine Water, Sediment, and Biota Samples on Femtogram Levels by GC-MS/MS.
- Author
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Bünning TH, Strehse JS, Hollmann AC, Bötticher T, and Maser E
- Abstract
To determine the amount of the explosives 1,3-dinitrobenzene, 2,4-dinitrotoluene, 2,4,6-trinitrotoluene, and its metabolites in marine samples, a toolbox of methods was developed to enhance sample preparation and analysis of various types of marine samples, such as water, sediment, and different kinds of biota. To achieve this, established methods were adapted, improved, and combined. As a result, if explosive concentrations in sediment or mussel samples are greater than 10 ng per g, direct extraction allows for time-saving sample preparation; if concentrations are below 10 ng per g, techniques such as freeze-drying, ultrasonic, and solid-phase extraction can help to detect even picogram amounts. Two different GC-MS/MS methods were developed to enable the detection of these explosives in femtogram per microliter. With a splitless injector, limits of detection (LODs) between 77 and 333 fg/µL could be achieved in only 6.25 min. With the 5 µL programmable temperature vaporization-large volume method (PTV-LVI), LODs between 8 and 47 fg/µL could be achieved in less than 7 min. The detection limits achieved by these methods are among the lowest published to date. Their reliability has been tested and confirmed by measuring large and diverse sample sets.
- Published
- 2021
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91. Longitudinal Changes in Fecal Calprotectin Levels Among Pregnant Women With and Without Inflammatory Bowel Disease and Their Babies.
- Author
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Kim ES, Tarassishin L, Eisele C, Barre A, Nair N, Rendon A, Hawkins K, Debebe A, White S, Thjømøe A, Mørk E, Bento-Miranda M, Panchal H, Agrawal M, Patel A, Chen CL, Kornbluth A, George J, Legnani P, Maser E, Loudon H, Mella MT, Stone J, Dubinsky M, Sabino J, Torres J, Colombel JF, Peter I, and Hu J
- Subjects
- Adult, Anti-Bacterial Agents administration & dosage, Bacteria drug effects, Bacteria immunology, Bacteria isolation & purification, Case-Control Studies, Child, Preschool, Colitis, Ulcerative drug therapy, Colitis, Ulcerative immunology, Colonoscopy, Crohn Disease drug therapy, Crohn Disease immunology, Feces chemistry, Female, Gastrointestinal Microbiome drug effects, Gastrointestinal Microbiome immunology, Humans, Infant, Infant, Newborn, Intestinal Mucosa immunology, Intestinal Mucosa microbiology, Longitudinal Studies, Male, Pregnancy, Pregnancy Complications drug therapy, Pregnancy Complications immunology, Prenatal Exposure Delayed Effects immunology, Prospective Studies, Severity of Illness Index, Colitis, Ulcerative diagnosis, Crohn Disease diagnosis, Leukocyte L1 Antigen Complex analysis, Pregnancy Complications diagnosis, Prenatal Exposure Delayed Effects diagnosis
- Abstract
Background & Aims: The effect of pregnancy on inflammatory bowel disease (IBD) remains poorly understood. We aimed to monitor intestinal inflammation using fecal calprotectin (FC) in pregnant women and their babies during early life., Methods: Pregnant women with or without IBD and their infants were prospectively enrolled. FC levels were measured at each trimester of pregnancy and in babies throughout the first 3 years of life. Repeated-measures analysis was applied to investigate changes in FC levels while adjusting for confounders. The FC levels were correlated with the bacterial abundance in both mothers and babies., Results: Six hundred and fourteen fecal samples from 358 mothers (98 with IBD) and 1005 fecal samples from 289 infants (76 born to IBD mothers) were analyzed. Pregnant Patients with IBD maintained higher FC levels through pregnancy compared with controls (P = 7.5 × 10
-54 ). FC gradually increased in controls and declined in Patients with IBD throughout pregnancy (P for interaction = 5.8 × 10-7 ). Babies born to mothers with IBD presented with significantly higher FC levels than those born to controls up to 3 years of age, after adjusting for sex, delivery mode, feeding behavior, and antibiotics exposure (2 weeks to 3 months of age, P = .015; 12-36 months of age, P = .00003). Subdoligranulum, Roseburia, Fusicatenibacter, and Alistipes negatively correlated, and Streptococcus, Prevotella, Escherichia-Shigella, and Bifidobacterium positively correlated with maternal FC levels at T3. Faecalibacterium, Bifidobacterium, and Alistipes showed negative correlations, and Streptococcus were positively correlated with FC levels within 3 months of birth., Conclusions: Pregnancy is associated with decreased inflammatory activity in mothers with IBD. Higher FC levels in babies born to mothers with IBD suggest subclinical inflammation in early life, the long-term consequences of which are uncertain., (Copyright © 2021. Published by Elsevier Inc.)- Published
- 2021
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92. Acute aquatic toxicity of arsenic-based chemical warfare agents to Daphnia magna.
- Author
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Czub M, Nawała J, Popiel S, Brzeziński T, Maszczyk P, Sanderson H, Maser E, Gordon D, Dziedzic D, Dawidziuk B, Pijanowska J, Fabisiak J, Szubska M, Lang T, Vanninen P, Niemikoski H, Missiaen T, Lehtonen KK, Bełdowski J, and Kotwicki L
- Subjects
- Animals, Arsenic analysis, Arsenicals analysis, Chemical Warfare Agents analysis, Chlorides analysis, Ecosystem, Lethal Dose 50, Limit of Detection, Seawater chemistry, Toxicity Tests, Acute, Water Pollutants, Chemical analysis, Arsenic toxicity, Chemical Warfare Agents toxicity, Daphnia drug effects, Water Pollutants, Chemical toxicity
- Abstract
Sea dumping of chemical warfare (CW) took place worldwide during the 20th century. Submerged CW included metal bombs and casings that have been exposed for 50-100 years of corrosion and are now known to be leaking. Therefore, the arsenic-based chemical warfare agents (CWAs), pose a potential threat to the marine ecosystems. The aim of this research was to support a need for real-data measurements for accurate risk assessments and categorization of threats originating from submerged CWAs. This has been achieved by providing a broad insight into arsenic-based CWAs acute toxicity in aquatic ecosystems. Standard tests were performed to provide a solid foundation for acute aquatic toxicity threshold estimations of CWA: Lewisite, Adamsite, Clark I, phenyldichloroarsine (PDCA), CWA-related compounds: TPA, arsenic trichloride and four arsenic-based CWA degradation products. Despite their low solubility, during the 48 h exposure, all CWA caused highly negative effects on Daphnia magna. PDCA was very toxic with 48 h D. magna LC50 at 0.36 μg × L
-1 and Lewisite with EC50 at 3.2 μg × L-1 . Concentrations at which no immobilization effects were observed were slightly above the analytical Limits of Detection (LOD) and Quantification (LOQ). More water-soluble CWA degradation products showed no effects at concentrations up to 100 mg × L-1 ., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2021
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93. The explosive trinitrotoluene (TNT) induces gene expression of carbonyl reductase in the blue mussel (Mytilus spp.): a new promising biomarker for sea dumped war relicts?
- Author
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Strehse JS, Brenner M, Kisiela M, and Maser E
- Subjects
- Alcohol Oxidoreductases genetics, Animals, Computational Biology, Dose-Response Relationship, Drug, Environmental Biomarkers genetics, Enzyme Induction, Mytilus edulis enzymology, Mytilus edulis genetics, Oceans and Seas, Risk Assessment, World War II, Alcohol Oxidoreductases biosynthesis, Bombs, Environmental Monitoring, Explosive Agents toxicity, Hazardous Waste, Mytilus edulis drug effects, Trinitrotoluene toxicity, Water Pollutants, Chemical toxicity
- Abstract
Millions of tons of all kind of munitions, including mines, bombs and torpedoes have been dumped after World War II in the marine environment and do now pose a new threat to the seas worldwide. Beside the acute risk of unwanted detonation, there is a chronic risk of contamination, because the metal vessels corrode and the toxic and carcinogenic explosives (trinitrotoluene (TNT) and metabolites) leak into the environment. While the mechanism of toxicity and carcinogenicity of TNT and its derivatives occurs through its capability of inducing oxidative stress in the target biota, we had the idea if TNT can induce the gene expression of carbonyl reductase in blue mussels. Carbonyl reductases are members of the short-chain dehydrogenase/reductase (SDR) superfamily. They metabolize xenobiotics bearing carbonyl functions, but also endogenous signal molecules such as steroid hormones, prostaglandins, biogenic amines, as well as sugar and lipid peroxidation derived reactive carbonyls, the latter providing a defence mechanism against oxidative stress and reactive oxygen species (ROS). Here, we identified and cloned the gene coding for carbonyl reductase from the blue mussel Mytilus spp. by a bioinformatics approach. In both laboratory and field studies, we could show that TNT induces a strong and concentration-dependent induction of gene expression of carbonyl reductase in the blue mussel. Carbonyl reductase may thus serve as a biomarker for TNT exposure on a molecular level which is useful to detect TNT contaminations in the environment and to perform a risk assessment both for the ecosphere and the human seafood consumer.
- Published
- 2020
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94. Marine bivalves as bioindicators for environmental pollutants with focus on dumped munitions in the sea: A review.
- Author
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Strehse JS and Maser E
- Subjects
- Animals, Environmental Monitoring, Humans, Oceans and Seas, Bivalvia, Environmental Biomarkers, Environmental Pollutants, Water Pollutants, Chemical
- Abstract
The seas worldwide are threatened by a "new" source of pollution. Munitions dumped into the seas worldwide will corrode and start to leak. Their impacts on the environment and on human health are now more than ever subject of scientific research. Bivalves are a first choice bioindicator and their importance is demonstrated in numerous worldwide studies as well as their integration in important monitoring programs. In this review, the use of mussels in context with marine pollutants in recent years is pointed out in general but with a special focus on dumped conventional and chemical munitions. Monitoring experiments with mussels are able to generate large data sets, which should be mandatory included in decision support tools to increase their weight of evidence. The usefulness of mussels with regard to dumped munitions has clearly been documented in recent years and the further application of this important biomonitoring system is strongly recommended., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
- Full Text
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95. "Don't Blast": blast-in-place (BiP) operations of dumped World War munitions in the oceans significantly increase hazards to the environment and the human seafood consumer.
- Author
-
Maser E and Strehse JS
- Subjects
- Animals, Biological Monitoring, Consumer Product Safety, Explosive Agents adverse effects, Humans, Oceans and Seas, Risk Assessment, Seafood adverse effects, Waste Products adverse effects, Water Pollutants, Chemical adverse effects, Explosions, Explosive Agents analysis, Food Contamination analysis, Mytilus edulis chemistry, Seafood analysis, Waste Management, Waste Products analysis, Water Pollutants, Chemical analysis, World War I, World War II
- Abstract
The seas worldwide are threatened by a "new" source of pollution: millions of tons of all kind of warfare material have been dumped intentionally after World War I and II, in addition to mine barriers, failed detonations as well as shot down military planes and sunken ship wrecks carrying munitions. For example, in the German parts of the North and Baltic Sea approximately 1.6 million metric tons of toxic conventional explosives (TNT and others) and more than 5000 metric tons of chemical weapons are present. Such unexploded ordnance (UXO) constitutes a direct risk of detonation with increased human access (fisheries, water sports, cable constructions, wind farms and pipelines). Moreover, after more than 70 years of resting on the seabed, the metal shells of these munitions items corrode, such that chemicals leak out and distribute in the marine environment. Explosive chemicals such as TNT and its derivatives are known for their toxicity and carcinogenicity. In order not to endanger today's shipping traffic or the installation of pipelines and offshore plants by uncontrolled explosions, controlled blast-in-place (BiP) operations of these dangerous relics is a common practice worldwide. However, blast-in-place methods of in situ munitions disposal often result in incomplete (low-order) detonation, leaving substantial quantities of the explosive material in the environment. In the present free field investigation, we placed mussels (Mytilus spp.) as a biomonitoring system in an area of the Baltic Sea where BiP operations took place and where, by visual inspections by scientific divers, smaller and larger pieces of munitions-related materials were scattered on the seafloor. After recovery, the mussels were transferred to our laboratory and analyzed for TNT and its derivatives via gas chromatography and mass spectroscopy. Our data unequivocally demonstrate that low-order BiP operations of dumped munitions in the sea lead to multiple increases in the concentration of TNT and its metabolites in the mussels when compared to similar studies at corroding but still encased mines. For this reason, we explicitly criticize BiP operations because of the resulting environmental hazards, which can ultimately even endanger human seafood consumers.
- Published
- 2020
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96. Sex-specificity in lung cancer risk.
- Author
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Stapelfeld C, Dammann C, and Maser E
- Subjects
- Carcinogens toxicity, Female, Hormone Replacement Therapy adverse effects, Humans, Incidence, Lung Neoplasms pathology, Male, Proto-Oncogene Mas, Proto-Oncogenes genetics, Risk Factors, Sex Factors, United States epidemiology, Lung Neoplasms epidemiology, Lung Neoplasms etiology
- Abstract
Smoking is indisputably linked to lung cancer, yet only a small fraction of smokers develops this disease. Although previously tobacco-derived carcinogens and enzyme polymorphisms have been identified to increase the risk for smokers, recent epidemiological data suggest even sex-specificity as a new and additional factor. Obviously, women have a higher risk to develop lung cancer upon smoking than men. Overall, the odds ratio to develop lung cancer was almost three times greater for women than for men, DNA adduct levels were higher among females than in males and mutations in the tumor suppressor gene p53 and the proto-oncogene K-RAS were more frequently found in women than in men. A growing number of studies suggest that the interaction between tobacco carcinogens and endogenous and exogenous sex steroids may be important. Women taking hormone replacement therapy (HRT) or oral contraceptives experienced to have an increased lung cancer incidence. Epidemiologic data on HRT show a significant association between both a younger median age at lung cancer diagnosis and a shorter median survival time. Another clue is the significantly higher number of lung cancer diagnosed women who are largely premenopausal in comparison to diagnosed men in the same age or women with shorter menstrual cycles. Finally, the Coronary Drug Project (men who received estrogen preparations to reduce future cardiac events) was stopped when increased lung cancer mortality was observed in the estrogen therapy group. The present review provides a short overview and discussion on lung cancer risk and the impact thereon of sex., (© 2019 UICC.)
- Published
- 2020
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97. Infants born to mothers with IBD present with altered gut microbiome that transfers abnormalities of the adaptive immune system to germ-free mice.
- Author
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Torres J, Hu J, Seki A, Eisele C, Nair N, Huang R, Tarassishin L, Jharap B, Cote-Daigneault J, Mao Q, Mogno I, Britton GJ, Uzzan M, Chen CL, Kornbluth A, George J, Legnani P, Maser E, Loudon H, Stone J, Dubinsky M, Faith JJ, Clemente JC, Mehandru S, Colombel JF, and Peter I
- Subjects
- Adaptive Immunity, Adult, Animals, Bacteria classification, Bacteria isolation & purification, Dysbiosis immunology, Dysbiosis microbiology, Fecal Microbiota Transplantation methods, Feces microbiology, Female, Follow-Up Studies, Gastrointestinal Tract immunology, Gastrointestinal Tract microbiology, Germ-Free Life, Humans, Infant, Newborn, Inflammatory Bowel Diseases immunology, Male, Maternal-Fetal Exchange, Pregnancy, Pregnancy Complications immunology, Prenatal Exposure Delayed Effects immunology, Prospective Studies, Gastrointestinal Microbiome immunology, Inflammatory Bowel Diseases microbiology, Pregnancy Complications microbiology, Prenatal Exposure Delayed Effects microbiology
- Abstract
Background and Aims: Prenatal and early life bacterial colonisation is thought to play a major role in shaping the immune system. Furthermore, accumulating evidence links early life exposures to the risk of developing IBD later in life. We aimed to assess the effect of maternal IBD on the composition of the microbiome during pregnancy and on the offspring's microbiome., Methods: We prospectively examined the diversity and taxonomy of the microbiome of pregnant women with and without IBD and their babies at multiple time points. We evaluated the role of maternal IBD diagnosis, the mode of delivery, antibiotic use and feeding behaviour on the microbiome composition during early life. To assess the effects of IBD-associated maternal and infant microbiota on the enteric immune system, we inoculated germ-free mice (GFM) with the respective stool and profiled adaptive and innate immune cell populations in the murine intestines., Results: Pregnant women with IBD and their offspring presented with lower bacterial diversity and altered bacterial composition compared with control women and their babies. Maternal IBD was the main predictor of the microbiota diversity in the infant gut at 7, 14, 30, 60 and 90 days of life. Babies born to mothers with IBD demonstrated enrichment in Gammaproteobacteria and depletion in Bifidobacteria . Finally, GFM inoculated with third trimester IBD mother and 90-day infant stools showed significantly reduced microbial diversity and fewer class-switched memory B cells and regulatory T cells in the colon., Conclusion: Aberrant gut microbiota composition persists during pregnancy with IBD and alters the bacterial diversity and abundance in the infant stool. The dysbiotic microbiota triggered abnormal imprinting of the intestinal immune system in GFM., Competing Interests: Competing interests: JT received lecture fees from Takeda and Abbvie. JJF is a consultant for Janssen Research & Development and a member of the Scientific Advisory Board of Vedanta Biosciences. JFC reports receiving research grants from AbbVie, Janssen Pharmaceuticals and Takeda; receiving payment for lectures from AbbVie, Amgen, Allergan, Inc. Ferring Pharmaceuticals, Shire, and Takeda; receiving consulting fees from AbbVie, Amgen, Arena Pharmaceuticals, Boehringer Ingelheim, Celgene Corporation, Celltrion, Eli Lilly, Enterome, Ferring Pharmaceuticals, Genentech, Janssen Pharmaceuticals, Landos, Ipsen, Medimmune, Merck,Novartis, Pfizer, Shire, Takeda, Tigenix and holding stock options in Intestinal Biotech Development and Genfit., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2020
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98. Carbonyl reductase sniffer from the model organism daphnia: Cloning, substrate determination and inhibitory sensitivity.
- Author
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Strehse JS, Protopapas N, and Maser E
- Subjects
- Alcohol Oxidoreductases antagonists & inhibitors, Alcohol Oxidoreductases genetics, Animals, Arthropod Proteins antagonists & inhibitors, Arthropod Proteins genetics, Biocatalysis, Daphnia enzymology, Drosophila Proteins antagonists & inhibitors, Drosophila Proteins genetics, Drosophila Proteins metabolism, Drosophila melanogaster enzymology, Endosulfan chemistry, Endosulfan metabolism, Kinetics, Phenanthrenes chemistry, Phenanthrenes metabolism, Recombinant Proteins biosynthesis, Recombinant Proteins isolation & purification, Recombinant Proteins metabolism, Substrate Specificity, Alcohol Oxidoreductases metabolism, Arthropod Proteins metabolism, Cloning, Molecular
- Abstract
Carbonyl reductases (CRs) represent a fundamental enzymatic defense mechanism against oxidative stress. While commonly two carbonyl reductases (CBR1 and CBR3) are found in mammalian genomes, invertebrate model organisms like Drosophila melanogaster express no CR but a functional homolog to human CBR1, termed sniffer. The importance of sniffer could be demonstrated in D. melanogaster where it protected against age-dependent neurodegeneration. Interestingly, the microcrustacean Daphnia harbors four copies of the CR gene (CR1, CR2, CR3, CR4) in addition to one sniffer gene. Due to this unique equipment Daphnia is an ideal model organism to investigate the function of sniffer. Recombinant sniffer from D. magna und D. pules were produced in E. coli, purified by Ni-affinity chromatography and tested with a variety of aliphatic and aromatic diketones, reactive aldehydes and precursors of advanced glycation end products (AGE). The highest catalytic activities were determined for sniffer from D. pulex with the aromatic dicarbonyls 9,10-phenanthrenequinone (k
cat /Km = 2.6 s-1 x μM-1 ) and isatin (kcat /Km = 1.5 s-1 x μM-1 ). While sniffer from D. magna displayed preference for the same two substances, the respective catalytic activities were noticeably lower. Kinetic constants with aliphatic diketones were generally lower than those with aromatic dicarbonyls for both sniffer enzymes. The best aliphatic diketone as substrate for sniffer from D. magna and D. pulex was hexane-3,4-dione with kcat /Km = 0.23 s-1 μM-1 and kcat /Km = 0.35 s-1 μM-1 , respectively. Poor or no detectable activity of the two sniffer enzymes was seen with the aliphatic diketones 2,5-hexanedione and 3,5-heptanedione, the aldehydes butanal, hexanal, decanal, crotonaldehyde, acrolein, trans-2-hexenal, and the AGE precursors glyoxal, methylglyoxal, furfural and glyceraldehyde, indicating no physiological function in the metabolism of short-chain aldehydes. Substrate inhibition for both sniffer enzymes was observed with the quinone substrates 1,4-naphthoquinone and 2-methyl-1,4-benzoquinone. From a variety of pesticides endosulfan turned out as an effective inhibitor of the sniffer enzymes (Ki = 9.2 μM for sniffer from D. magna, Ki = 12.0 μM for sniffer from D. pulex). In conclusion, the present results on sniffer from the protein superfamily of the short-chain dehydrogenases/reductases (SDR) in Daphnia ssp. complement earlier studies on carbonyl reductases in the same species and indicate that Daphnia is an interesting model to study the overall response to carbonyl stress., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
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99. Potent inhibition of human carbonyl reductase 1 (CBR1) by the prenylated chalconoid xanthohumol and its related prenylflavonoids isoxanthohumol and 8-prenylnaringenin.
- Author
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Seliger JM, Martin HJ, Maser E, and Hintzpeter J
- Subjects
- Alcohol Oxidoreductases antagonists & inhibitors, Alcohol Oxidoreductases genetics, Cell Line, Tumor, Chalcones chemistry, Daunorubicin chemistry, Daunorubicin metabolism, Flavanones metabolism, Flavonoids metabolism, Hexanones chemistry, Hexanones metabolism, Humans, Inhibitory Concentration 50, Kinetics, Oxidation-Reduction, Propiophenones metabolism, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, Substrate Specificity, Xanthones metabolism, Alcohol Oxidoreductases metabolism, Flavanones chemistry, Flavonoids chemistry, Propiophenones chemistry, Xanthones chemistry
- Abstract
In terms of drug disposal and metabolism SDR21C1 (carbonyl reductase 1; CBR1) exerts an assorted substrate spectrum among a large variety of clinically relevant substances. Additionally, this short-chain dehydrogenase/reductase is extensively expressed in most tissues of the human body, thus underpinning its role in xenobiotic metabolism. Reduction of the chemotherapeutic daunorubicin (DAUN) to daunorubicinol (DAUNol) is a prominent example of its metabolic properties in terms of chemoresistance and cardiotoxicity. The hop-derived prenylated chalcone xanthohumol (XN) and its physiological metabolites isoxanthohumol (IX) and 8-prenylnaringenin (8-PN) have previously been reported to inhibit other DAUN reducing reductases and dehydrogenases including AKR1B1 and AKR1B10. Also with regard to their effects by means of interacting with cancer-related molecular pathways, XN and related prenylated flavonoids in particular have been in the focus of recent studies. In this study, inhibitory properties of these substances were examined with CBR1-mediated 2,3-hexanedione and DAUN reduction. All substances tested in this study turned out to efficiently inhibit recombinant human CBR1 within a low micromolar to submicromolar range. Among the substances tested, 8-PN turned out to be the most effective inhibitor when using 2,3-hexanedione as a substrate (K
i (app) = 180 ± 20 nM). Inhibition rates of recombinant CBR1-mediated DAUN reduction were somewhat weaker with IC50-values ranging from 11 to 20 μM. XN, IX and 8-PN also efficiently inhibited DAUN reduction by SW480 colon adenocarcinoma cytosol (IC50 = 3.71 ± 0.26 μM with 8-PN as inhibitor). This study identifies prenylated inhibitors, which might potentially interact with endogenous CBR1-driven (de-)toxication systems., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
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100. Expression and activity of the cortisol-activating enzyme 11β-hydroxysteroid dehydrogenase type 1 is tissue and species-specific.
- Author
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Dammann C, Stapelfeld C, and Maser E
- Subjects
- Animals, Diabetes Mellitus, Type 2 etiology, Humans, Hydrocortisone metabolism, Obesity, Abdominal etiology, Species Specificity, Tissue Distribution, 11-beta-Hydroxysteroid Dehydrogenase Type 1 metabolism
- Abstract
The microsomal enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) interconverts glucocorticoid receptor-inert cortisone (11-dehydrocorticosterone in rodents) to its receptor-active form cortisol (corticosterone in rodents). Thus, 11β-HSD1 amplifies glucocorticoid action at the tissue level. According to the current literature, dysregulation of glucocorticoid signaling may contribute to the pathogenesis of the metabolic syndrome in which regeneration of cortisol by 11β-HSD1 may be an important factor. This is why the enzyme has been very intensely investigated as a potential therapeutic target to treat metabolic complications such as obesity and diabetes type 2. However, due to controversial results from the various animal and human studies as well as from different findings with regard to tissue-specific expression and activity, the varied results unfortunately do not yield a consistent picture. Therefore, the precise role of 11β-HSD1 in the development of complications associated with the metabolic syndrome has still not been deciphered yet. Overall, the prominent role of this enzyme in the pathogenesis of the metabolic syndrome becomes more and more dubious and therefore further studies are necessary to clarify its role finally. This short review gives an overview on the main contradicting findings on the role of 11β-HSD1 in the development of visceral obesity and diabetes type 2., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
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