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Lorensen MDBB, Hayat SY, Wellner N, Bjarnholt N, Janfelt C. Leaves of Cannabis sativa and their trichomes studied by DESI and MALDI mass spectrometry imaging for their contents of cannabinoids and flavonoids. Phytochem Anal 2023; 34:269-279. [PMID: 36654257 DOI: 10.1002/pca.3202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
INTRODUCTION In recent years, industrial production of Cannabis sativa has increased due to increased demand of medicinal products based on the plant. In these medicinal products, it is mainly the contents of cannabinoids like THCA and CBDA which are of interest, but also the flavonoids of C. sativa have pharmaceutical interest. OBJECTIVES The primary aim is to study the distribution of the different cannabinoids in leaves of C. sativa and specifically to which extent they are located on the trichomes found on the surface of C. sativa leaves. Desorption electrospray ionization (DESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry imaging (MSI) provide non-targeted imaging of numerous compounds in the same experiment. Therefore, the distribution of flavonoids is also mapped in the same experiments. MATERIAL AND METHODS Fan leaves from C. sativa were imaged in the lateral dimension using direct DESI-MSI as well as indirect DESI-MSI via a porous PTFE surface using pixel sizes of 150-200 μm. For cross sections of sugar leaves, MALDI-MSI was performed at 20 μm pixel size. RESULTS From indirect DESI-MSI experiments, a connection was made between the cannabinoid CBGA and capitate-stalked trichomes. Other cannabinoids like THCA/CBDA (isomers, which are not resolved in an MSI experiment) were also detected in the capitate-stalked trichomes, but in addition to this also in the small glandular trichomes. MALDI-MSI experiments on cross sections of sugar leaves confirmed that the cannabinoids were not an integral part of the leaf tissue itself, but originated from the trichomes on the surface of the leaf. CONCLUSION The study provides visual evidence that the cannabinoids are produced and accumulated in the trichomes of C. sativa leaves.
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Affiliation(s)
| | - Sidra Yasmine Hayat
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Nanna Bjarnholt
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Christian Janfelt
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Monti G, Kjolby M, Jensen AMG, Allen M, Reiche J, Møller PL, Comaposada-Baró R, Zolkowski BE, Vieira C, Jørgensen MM, Holm IE, Valdmanis PN, Wellner N, Vægter CB, Lincoln SJ, Nykjær A, Ertekin-Taner N, Young JE, Nyegaard M, Andersen OM. Expression of an alternatively spliced variant of SORL1 in neuronal dendrites is decreased in patients with Alzheimer's disease. Acta Neuropathol Commun 2021; 9:43. [PMID: 33726851 PMCID: PMC7962264 DOI: 10.1186/s40478-021-01140-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 02/26/2021] [Indexed: 12/13/2022] Open
Abstract
SORL1 is strongly associated with both sporadic and familial forms of Alzheimer's disease (AD), but a lack of information about alternatively spliced transcripts currently limits our understanding of the role of SORL1 in AD. Here, we describe a SORL1 transcript (SORL1-38b) characterized by inclusion of a novel exon (E38b) that encodes a truncated protein. We identified E38b-containing transcripts in several brain regions, with the highest expression in the cerebellum and showed that SORL1-38b is largely located in neuronal dendrites, which is in contrast to the somatic distribution of transcripts encoding the full-length SORLA protein (SORL1-fl). SORL1-38b transcript levels were significantly reduced in AD cerebellum in three independent cohorts of postmortem brains, whereas no changes were observed for SORL1-fl. A trend of lower 38b transcript level in cerebellum was found for individuals carrying the risk variant at rs2282649 (known as SNP24), although not reaching statistical significance. These findings suggest synaptic functions for SORL1-38b in the brain, uncovering novel aspects of SORL1 that can be further explored in AD research.
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Affiliation(s)
- Giulia Monti
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Mads Kjolby
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Anne Mette G Jensen
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Mariet Allen
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Juliane Reiche
- Department of Biochemistry, Jena University Hospital, Jena, Germany
| | - Peter L Møller
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Raquel Comaposada-Baró
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Bartlomiej E Zolkowski
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Cármen Vieira
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Margarita Melnikova Jørgensen
- Department of Clinical Medicine, Aarhus University, Aarhus C, Denmark
- Department of Pathology, Randers Regional Hospital, Randers, Denmark
| | - Ida E Holm
- Department of Clinical Medicine, Aarhus University, Aarhus C, Denmark
- Department of Pathology, Randers Regional Hospital, Randers, Denmark
| | - Paul N Valdmanis
- Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, WA, USA
| | - Niels Wellner
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Christian B Vægter
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Sarah J Lincoln
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Anders Nykjær
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
- Center for Proteins in Memory - PROMEMO, Danish National Research Foundation, Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Nilüfer Ertekin-Taner
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Department of Neurology, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Jessica E Young
- Department of Pathology, Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | - Mette Nyegaard
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark
| | - Olav M Andersen
- Department of Biomedicine, Aarhus University, Høegh-Guldbergs Gade 10, 8000, Aarhus C, Denmark.
- Center for Proteins in Memory - PROMEMO, Danish National Research Foundation, Department of Biomedicine, Aarhus University, Aarhus C, Denmark.
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Olsen D, Wellner N, Kaas M, de Jong IEM, Sotty F, Didriksen M, Glerup S, Nykjaer A. Altered dopaminergic firing pattern and novelty response underlie ADHD-like behavior of SorCS2-deficient mice. Transl Psychiatry 2021; 11:74. [PMID: 33495438 PMCID: PMC7835366 DOI: 10.1038/s41398-021-01199-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 12/12/2020] [Accepted: 01/05/2021] [Indexed: 01/03/2023] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is the most frequently diagnosed neurodevelopmental disorder worldwide. Affected individuals present with hyperactivity, inattention, and cognitive deficits and display a characteristic paradoxical response to drugs affecting the dopaminergic system. However, the underlying pathophysiology of ADHD and how this relates to dopaminergic transmission remains to be fully understood. Sorcs2-/- mice uniquely recapitulate symptoms reminiscent of ADHD in humans. Here, we show that lack of SorCS2 in mice results in lower sucrose intake, indicating general reward deficits. Using in-vivo recordings, we further find that dopaminergic transmission in the ventral tegmental area (VTA) is shifted towards a more regular firing pattern with marked reductions in the relative occurrence of irregular firing in Sorcs2-/- mice. This was paralleled by abnormal acute behavioral responses to dopamine receptor agonists, suggesting fundamental differences in dopaminergic circuits and indicating a perturbation in the balance between the activities of the postsynaptic dopamine receptor DRD1 and the presynaptic inhibitory autoreceptor DRD2. Interestingly, the hyperactivity and drug response of Sorcs2-/- mice were markedly affected by novelty. Taken together, our findings show how loss of a candidate ADHD-risk gene has marked effects on dopaminergic circuit function and the behavioral response to the environment.
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Affiliation(s)
- Ditte Olsen
- grid.7048.b0000 0001 1956 2722Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000 Aarhus C, Denmark ,grid.424580.f0000 0004 0476 7612Neurodegeneration and Biologics, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark ,grid.7048.b0000 0001 1956 2722Present Address: Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000 Aarhus C, Denmark
| | - Niels Wellner
- grid.7048.b0000 0001 1956 2722Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000 Aarhus C, Denmark ,grid.7048.b0000 0001 1956 2722Danish Research Institute of Translational Neuroscience DANDRITE Nordic-EMBL Partnership, Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000 Aarhus C, Denmark
| | - Mathias Kaas
- grid.7048.b0000 0001 1956 2722Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000 Aarhus C, Denmark
| | - Inge E. M. de Jong
- grid.424580.f0000 0004 0476 7612Neurodegeneration and Biologics, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Florence Sotty
- grid.424580.f0000 0004 0476 7612Neurodegeneration and Biologics, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Michael Didriksen
- grid.424580.f0000 0004 0476 7612Neurodegeneration and Biologics, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Simon Glerup
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark.
| | - Anders Nykjaer
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark. .,Danish Research Institute of Translational Neuroscience DANDRITE Nordic-EMBL Partnership, Department of Biomedicine, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark. .,The Danish National Research Foundation Center PROMEMO, Aarhus University, Hoegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark. .,Department of Neurosurgery, Skejby University Hospital, Palle Juul-Jensens Blvd. 99, DK-8200, Aarhus N, Denmark.
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Graae AS, Grarup N, Ribel-Madsen R, Lystbæk SH, Boesgaard T, Staiger H, Fritsche A, Wellner N, Sulek K, Kjolby M, Backe MB, Chubanava S, Prats C, Serup AK, Birk JB, Dubail J, Gillberg L, Vienberg SG, Nykjær A, Kiens B, Wojtaszewski JFP, Larsen S, Apte SS, Häring HU, Vaag A, Zethelius B, Pedersen O, Treebak JT, Hansen T, Holst B. ADAMTS9 Regulates Skeletal Muscle Insulin Sensitivity Through Extracellular Matrix Alterations. Diabetes 2019; 68:502-514. [PMID: 30626608 PMCID: PMC6385758 DOI: 10.2337/db18-0418] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 12/14/2018] [Indexed: 12/17/2022]
Abstract
The ADAMTS9 rs4607103 C allele is one of the few gene variants proposed to increase the risk of type 2 diabetes through an impairment of insulin sensitivity. We show that the variant is associated with increased expression of the secreted ADAMTS9 and decreased insulin sensitivity and signaling in human skeletal muscle. In line with this, mice lacking Adamts9 selectively in skeletal muscle have improved insulin sensitivity. The molecular link between ADAMTS9 and insulin signaling was characterized further in a model where ADAMTS9 was overexpressed in skeletal muscle. This selective overexpression resulted in decreased insulin signaling presumably mediated through alterations of the integrin β1 signaling pathway and disruption of the intracellular cytoskeletal organization. Furthermore, this led to impaired mitochondrial function in mouse muscle-an observation found to be of translational character because humans carrying the ADAMTS9 risk allele have decreased expression of mitochondrial markers. Finally, we found that the link between ADAMTS9 overexpression and impaired insulin signaling could be due to accumulation of harmful lipid intermediates. Our findings contribute to the understanding of the molecular mechanisms underlying insulin resistance and type 2 diabetes and point to inhibition of ADAMTS9 as a potential novel mode of treating insulin resistance.
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Affiliation(s)
- Anne-Sofie Graae
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niels Grarup
- Section for Metabolic Genetics, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rasmus Ribel-Madsen
- Section for Metabolic Genetics, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Endocrinology, Rigshospitalet, Copenhagen, Denmark
- Danish Diabetes Academy, Novo Nordisk Foundation, Odense, Denmark
- Steno Diabetes Center, Gentofte, Denmark
| | - Sara H Lystbæk
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Trine Boesgaard
- Section for Metabolic Genetics, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Harald Staiger
- Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research, Tübingen, Germany
- Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine IV, University Hospital of Tübingen, Tübingen, Germany
| | - Niels Wellner
- The Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience, Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Karolina Sulek
- Section for Integrative Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mads Kjolby
- Danish Diabetes Academy, Novo Nordisk Foundation, Odense, Denmark
- The Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience, Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Marie Balslev Backe
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sabina Chubanava
- Section for Integrative Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Clara Prats
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Annette K Serup
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Jesper B Birk
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Johanne Dubail
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH
| | | | - Sara G Vienberg
- Section for Integrative Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anders Nykjær
- The Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience, Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Bente Kiens
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen F P Wojtaszewski
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Steen Larsen
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Suneel S Apte
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH
| | - Hans-Ulrich Häring
- Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich, University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine IV, University Hospital of Tübingen, Tübingen, Germany
| | - Allan Vaag
- Cardiovascular and Metabolic Disease Translational Medicine Unit, Early Clinical Development, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Björn Zethelius
- Geriatrics, Department of Public Health and Caring Services, Uppsala University, Uppsala, Sweden
| | - Oluf Pedersen
- Section for Metabolic Genetics, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jonas T Treebak
- Section for Integrative Physiology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Torben Hansen
- Section for Metabolic Genetics, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Birgitte Holst
- Section for Metabolic Receptology, Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Zhao X, Moates G, Wellner N, Collins S, Coleman M, Waldron K. Chemical characterisation and analysis of the cell wall polysaccharides of duckweed (Lemna minor). Carbohydr Polym 2014; 111:410-8. [DOI: 10.1016/j.carbpol.2014.04.079] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/15/2014] [Accepted: 04/18/2014] [Indexed: 11/16/2022]
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Wellner N, Scholl S. Kontinuierliche Entwässerung ionischer Flüssigkeiten im Fallfilmverdampfer. CHEM-ING-TECH 2013. [DOI: 10.1002/cite.201250668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Janfelt C, Wellner N, Hansen HS, Hansen SH. Displaced dual-mode imaging with desorption electrospray ionization for simultaneous mass spectrometry imaging in both polarities and with several scan modes. J Mass Spectrom 2013; 48:361-366. [PMID: 23494793 DOI: 10.1002/jms.3166] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/08/2013] [Accepted: 01/09/2013] [Indexed: 06/01/2023]
Abstract
Displaced dual-mode imaging (DDI) is introduced as a method for simultaneous imaging in positive and negative-ion mode on the same sample with desorption electrospray ionization imaging, as well as a method for simultaneous imaging in full-scan and tandem mass spectrometry (MS/MS) mode. DDI is performed by using a smaller row distance in the y-direction than the desired image resolution and recording for example every second row in positive-ion mode and the other half of the rows in negative-ion mode, thus resulting in two separate images. This causes some degree of oversampling, which is thus utilized to obtain complementary mass spectrometric of the sample. Imaging with both polarities is exemplified on an imprint of a Hypericum perforatum leaf containing secondary metabolites which ionize in both polarites and a mouse kidney containing phospholipids which ionize in positive or negative mode only. Simultaneous full-scan and MS/MS imaging was demonstrated on the same mouse kidney, as the mouse had been given a relatively low dose of the antidepressive drug amitriptyline. While the full-scan data allowed imaging of the endogenous phospholipids, the drug and its metabolites were only visible in the MS/MS images. The latter approach is useful, for example in whole-body imaging experiments where the full-scan data gives an overview of the tissue, and the MS/MS mode provides the sensitivity to image trace amounts of drugs and metabolites.
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Affiliation(s)
- Christian Janfelt
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.
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Wellner N, Diep TA, Janfelt C, Hansen HS. N-acylation of phosphatidylethanolamine and its biological functions in mammals. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:652-62. [DOI: 10.1016/j.bbalip.2012.08.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 08/30/2012] [Accepted: 08/31/2012] [Indexed: 12/22/2022]
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Janfelt C, Wellner N, Leger P, Kokesch‐Himmelreich J, Hansen SH, Charriaut‐Marlangue C, Hansen HS. Visualization by mass spectrometry of 2‐dimensional changes in rat brain lipids, including
N
‐acylphosphatidylethanolamines, during neonatal brain ischemia. FASEB J 2012; 26:2667-73. [DOI: 10.1096/fj.11-201152] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Christian Janfelt
- Department of Pharmaceutics and Analytical ChemistryUniversity of CopenhagenDenmark
| | - Niels Wellner
- Department of Pharmacology and PharmacotherapyFaculty of Pharmaceutical SciencesUniversity of CopenhagenDenmark
| | - Pierre‐Louis Leger
- Institut National de la Santé et de la Recherche Médicale (INSERM) U676Hôpital Robert DebréUniversite‐Denis Diderot‐Paris 7ParisFrance
| | | | - Steen Honoré Hansen
- Department of Pharmaceutics and Analytical ChemistryUniversity of CopenhagenDenmark
| | - Christiane Charriaut‐Marlangue
- Institut National de la Santé et de la Recherche Médicale (INSERM) U676Hôpital Robert DebréUniversite‐Denis Diderot‐Paris 7ParisFrance
| | - Harald Severin Hansen
- Department of Pharmacology and PharmacotherapyFaculty of Pharmaceutical SciencesUniversity of CopenhagenDenmark
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Wellner N, Tsuboi K, Madsen AN, Holst B, Diep TA, Nakao M, Tokumura A, Burns MP, Deutsch DG, Ueda N, Hansen HS. Studies on the anorectic effect of N-acylphosphatidylethanolamine and phosphatidylethanolamine in mice. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1811:508-12. [DOI: 10.1016/j.bbalip.2011.06.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 05/28/2011] [Accepted: 06/16/2011] [Indexed: 12/13/2022]
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Hansen KB, Rosenkilde MM, Knop FK, Wellner N, Diep TA, Rehfeld JF, Andersen UB, Holst JJ, Hansen HS. 2-Oleoyl glycerol is a GPR119 agonist and signals GLP-1 release in humans. J Clin Endocrinol Metab 2011; 96:E1409-17. [PMID: 21778222 DOI: 10.1210/jc.2011-0647] [Citation(s) in RCA: 199] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Dietary fat is thought to stimulate release of incretin hormones via activation of fatty acid receptors in the intestine. However, dietary fat (triacylglycerol) is digested to 2-monoacylglycerol and fatty acids. Activation of G protein-coupled receptor 119 (GPR119) stimulates glucagon-like peptide-1 (GLP-1) release from the intestinal L-cells. We aimed to investigate if 2-oleoyl glycerol (2OG) can activate GPR119 in vitro and stimulate GLP-1 secretion in vivo. RESEARCH DESIGN AND METHODS Agonist activity for various lipids was tested on transiently expressed human GPR119 in COS-7 cells. The effect of a jejunal bolus of 2 g 2OG on plasma levels of GLP-1 was evaluated in eight healthy human volunteers. The effect of 2OG was compared to an equimolar amount of oleic acid, a degradation product from 2OG, and the vehicle, glycerol. Digestion of 5 ml olive oil with pancreatic lipase will result in formation of approximately 2 g 2OG and 3.2 g oleic acid. RESULTS 2OG and other 2-monoacylglycerols increased intracellular concentrations of cAMP in GPR119-expressing COS-7 cells (2OG EC(50) = 2.5 μm). Administration of 2OG to humans significantly increased plasma GLP-1 (0-25 min) when compared to the two controls, oleic acid and vehicle. Plasma levels of glucose-dependent insulinotropic polypeptide also increased. CONCLUSION 2OG and other 2-monoacylglycerols formed during fat digestion can activate GPR119 and cause incretin release from the human intestine. This mechanism is likely to contribute to the known stimulatory effect of dietary fat on incretin secretion, and it indicates that GPR119 is a fat sensor.
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Affiliation(s)
- Katrine B Hansen
- Department of Clinical Physiology, Glostrup Hospital, 2600 Glostrup, Denmark
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Diep TA, Madsen AN, Holst B, Kristiansen MM, Wellner N, Hansen SH, Hansen HS. Dietary fat decreases intestinal levels of the anorectic lipids through a fat sensor. FASEB J 2010; 25:765-74. [PMID: 20959516 DOI: 10.1096/fj.10-166595] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
This study was undertaken to investigate the link between dietary fat content and intestinal levels of anorectic N-acylethanolamines (NAEs), including oleoylethanolamide (OEA), palmitoylethanolamide (PEA), and linoleoylethanolamide (LEA). Male rats were fed high-fat diets (HFDs) with variable percentages of fat [20-45% of total energy (E%)] for 1-7 d; afterward, the jejunums were isolated, and jejunal NAE levels were measured by liquid-chromatography mass spectrometry. Enzyme activities and mRNA expression levels were measured for two synthesizing enzymes, N-acylphosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and glycerophosphodiesterase (GDE1), and one degrading enzyme, fatty acid amide hydrolase (FAAH). We found a dose-response relation between the quantity/percentage of dietary fat, irrespective of the energy density, and the reduction of intestinal levels of OEA, PEA, and LEA. The reductions were present after 1 d of 45E% HFD. LEA, the major NAE species, was shown to have an anorectic potency slightly less than that of OEA but higher than PEA. Regulation at the enzyme level seems not to explain the changes in NAE levels. The results suggest the presence of a fat sensor, mediating the reduced intestinal NAE levels. The intestinal NAE levels are reduced in a dose- and time-dependent manner in response to dietary fat intake, and this may contribute to the well-known hyperphagic effect of HFDs.
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Affiliation(s)
- Thi Ai Diep
- Department of Pharmacology and Pharmacotheraphy, Faculty of Pharmaceutical Sciences, University of Copenhagen, Copenhagen, Denmark
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16
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Reis K, Pereira J, Smith A, Carvalho C, Wellner N, Yakimets I. Characterization of polyhydroxybutyrate-hydroxyvalerate (PHB-HV)/maize starch blend films. J FOOD ENG 2008. [DOI: 10.1016/j.jfoodeng.2008.04.022] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Laos K, Parker R, Moffat J, Wellner N, Ring S. The adsorption of globular proteins, bovine serum albumin and β-lactoglobulin, on poly-l-lysine–furcellaran multilayers. Carbohydr Polym 2006. [DOI: 10.1016/j.carbpol.2006.01.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Byaruhanga YB, Emmambux MN, Belton PS, Wellner N, Ng KG, Taylor JRN. Alteration of kafirin and kafirin film structure by heating with microwave energy and tannin complexation. J Agric Food Chem 2006; 54:4198-207. [PMID: 16756347 DOI: 10.1021/jf052942z] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Heating with microwave energy and tannin complexation of kafirin both increase the tensile strength of cast kafirin bioplastic films. The effects of these treatments on the molecular structure of kafirin and of kafirin in the film were investigated. SDS-PAGE of heated wet kafirin showed an increase in kafirin oligomers. Disulfide groups increased in heated kafirin and in films made from the heated kafirin. Fourier transform infrared (FTIR) spectroscopy of heated kafirin and films made from the heated kafirin indicated an increase in beta-sheet conformation. In contrast, kafirin complexation with tannic acid (TA) and sorghum condensed tannin (SCT) resulted in a slight decrease in beta-sheet conformation in the kafirin and a larger decrease in the kafirin in the films. Raman spectroscopy showed that, with TA, there was a shift in peak from 1710 to 1728 cm(-1) for kafirin-tannic acid complexes, indicating kafirin and tannic acid interaction. The protein conformational changes presumably facilitated cross-linking between kafirin molecules and/or between kafirin and the tannins. Thus, although both heating with microwave energy and tannin complexation cause cross-linking of kafirin to increase film tensile strength, their effects on kafirin structure appear to be different.
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Affiliation(s)
- Y B Byaruhanga
- Department of Food Science and Technology, Makerere University, P.O. Box 7062, Kampala, Uganda
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19
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20
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Mills E, Parker M, Wellner N, Toole G, Feeney K, Shewry P. Chemical imaging: the distribution of ions and molecules in developing and mature wheat grain. J Cereal Sci 2005. [DOI: 10.1016/j.jcs.2004.09.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Halford N, Savage A, Wellner N, Mills E, Belton P, Shewry P. Use of Recombinant Peptides to Explore the Molecular Mechanism of Glutenprotein Viscoelasticity. Gluten Proteins 2004. [DOI: 10.1039/9781847552099-00054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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22
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Feeney KA, Wellner N, Gilbert SM, Halford NG, Tatham AS, Shewry PR, Belton PS. Molecular structures and interactions of repetitive peptides based on wheat glutenin subunits depend on chain length. Biopolymers 2003; 72:123-31. [PMID: 12583015 DOI: 10.1002/bip.10298] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Synthetic and recombinant peptide models of the central repetitive domain of the high molecular weight subunits of wheat glutenin with different numbers of the consensus repeat motifs PGQGQQ + GYYPTSLQQ (21, 45, 110, and 203 residues long) and a recombinant 58,000-Da relative molecular mass (M(r) 58,000) repetitive peptide from a single subunit (1Dx5) are studied using Fourier transform IR spectroscopy. The spectra of the dry peptides are very similar; at low water contents (<76% relative humidity) there is an increase in beta-sheet structures in all peptides. However, on further hydration the content of beta sheets decrease and more beta turns are observed. The changes during the second step of hydration are very marked in the 21 and 45 residue peptides, but they are less apparent in the longer perfect repeat peptides. In the 110 and 203 residue peptides hydration results in increased contents of intermolecular beta-sheets and less beta-turn formation. In contrast, the beta-turn content of the M(r) 58,000 peptide increases during the second hydration step. The decreased extent of structure changes with increasing chain length indicates that cumulative intermolecular interactions, in particular hydrogen bonds, are an important factor in determining the structures in the solid state. The regularity of the perfect repeat sequences in the 21, 45, 110, and 203 residue peptides may favor the formation of larger stretches of intermolecular beta sheets. In contrast, the M(r) 58,000 peptide contains imperfect repeats (in common with native glutenin subunits), which may limit its ability to form intermolecular beta sheets.
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Affiliation(s)
- K A Feeney
- IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS41 9AF, United Kingdom
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23
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Shewry PR, Gilbert SM, Savage AWJ, Tatham AS, Wan YF, Belton PS, Wellner N, D'Ovidio R, Békés F, Halford NG. Sequence and properties of HMW subunit 1Bx20 from pasta wheat (Triticum durum) which is associated with poor end use properties. Theor Appl Genet 2003; 106:744-750. [PMID: 12596005 DOI: 10.1007/s00122-002-1135-6] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2002] [Accepted: 07/23/2002] [Indexed: 05/24/2023]
Abstract
The gene encoding high-molecular-weight (HMW) subunit 1Bx20 was isolated from durum wheat cv. Lira. It encodes a mature protein of 774 amino acid residues with an M(r) of 83,913. Comparison with the sequence of subunit 1Bx7 showed over 96% identity, the main difference being the substitution of two cysteine residues in the N-terminal domain of subunit 1Bx7 with tyrosine residues in 1Bx20. Comparison of the structures and stabilities of the two subunits purified from wheat using Fourier-transform infra-red and circular dichroism spectroscopy showed no significant differences. However, incorporation of subunit 1Bx7 into a base flour gave increased dough strength and stability measured by Mixograph analysis, while incorporation of subunit 1Bx20 resulted in small positive or negative effects on the parameters measured. It is concluded that the different effects of the two subunits could relate to the differences in their cysteine contents, thereby affecting the cross-linking and hence properties of the glutenin polymers.
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Affiliation(s)
- P R Shewry
- Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, UK.
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24
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Wang Y, Belton PS, Bridon H, Garanger E, Wellner N, Parker ML, Grant A, Feillet P, Noel TR. Physicochemical studies of caroubin: a gluten-like protein. J Agric Food Chem 2001; 49:3414-3419. [PMID: 11453784 DOI: 10.1021/jf010076u] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
It has been reported that caroubin, a protein mixture obtained from carob seeds, has rheological properties similar to those of gluten. Comparative studies of the effects of hydration and temperature on caroubin and gluten were carried out with the aid of NMR, FTIR, scanning electron microscopy, and differential scanning calorimetry techniques. The results show that caroubin has a more ordered structure than gluten and that hydration has little effect on its secondary structure when compared to gluten. Caroubin is more easily accessible to water than gluten, suggesting that caroubin is more hydrophilic in nature. On hydration, caroubin, like gluten, forms fibrillar structures and sheets.
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Affiliation(s)
- Y Wang
- Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, United Kingdom
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Wilson RH, Smith AC, Kacuráková M, Saunders PK, Wellner N, Waldron KW. The mechanical properties and molecular dynamics of plant cell wall polysaccharides studied by Fourier-transform infrared spectroscopy. Plant Physiol 2000; 124:397-405. [PMID: 10982452 PMCID: PMC59152 DOI: 10.1104/pp.124.1.397] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2000] [Accepted: 05/24/2000] [Indexed: 05/18/2023]
Abstract
Polarized one- and two-dimensional infrared spectra were obtained from the epidermis of onion (Allium cepa) under hydrated and mechanically stressed conditions. By Fourier-transform infrared microspectroscopy, the orientation of macromolecules in single cell walls was determined. Cellulose and pectin exhibited little orientation in native epidermal cell walls, but when a mechanical stress was placed on the tissue these molecules showed distinct reorientation as the cells were elongated. When the stress was removed the tissue recovered slightly, but a relatively large plastic deformation remained. The plastic deformation was confirmed in microscopic images by retention of some elongation of cells within the tissue and by residual molecular orientation in the infrared spectra of the cell wall. Two-dimensional infrared spectroscopy was used to determine the nature of the interaction between the polysaccharide networks during deformation. The results provide evidence that cellulose and xyloglucan associate while pectin creates an independent network that exhibits different reorientation rates in the wet onion cell walls. The pectin chains respond faster to oscillation than the more rigid cellulose.
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Affiliation(s)
- R H Wilson
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, United Kingdom.
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26
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Gilbert SM, Wellner N, Belton PS, Greenfield JA, Siligardi G, Shewry PR, Tatham AS. Expression and characterisation of a highly repetitive peptide derived from a wheat seed storage protein. Biochim Biophys Acta 2000; 1479:135-46. [PMID: 11004535 DOI: 10.1016/s0167-4838(00)00059-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The high molecular weight (HMW) subunit group of wheat seed storage proteins impart elasticity to wheat doughs and glutens. They consist of three domains: non-repetitive N- and C-terminal domains, which contain cysteine residues for covalent cross-linking, and a central domain consisting of repeated sequences. The circular dichroism and infrared (IR) spectra of an intact HMW subunit were compared with those of a peptide corresponding to the central repetitive domain expressed in Escherichia coli. This allowed the structure of the central domain to be studied in the absence of the N- and C-terminal domains and the contributions of these domains to the structure of the whole protein to be determined. In solution the peptide showed the presence of beta-turns and polyproline II-like structure. Variable temperature studies indicated an equilibrium between these two structures, the polyproline II conformation predominating at low temperatures and the beta-turn conformation at higher temperatures. IR in the hydrated solid state also indicated the presence of beta-turns and intermolecular beta-sheet structures. In contrast, spectroscopy of the whole subunit showed the presence of alpha-helix in the N- and C-terminal domains. The content of beta-sheet was also higher in the whole subunit, indicating that the N- and C-terminal domains may promote the formation of intermolecular beta-sheet structures between the repetitive sequences, perhaps by aligning the molecules to promote interaction.
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Affiliation(s)
- S M Gilbert
- IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, UK
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Grant A, Belton PS, Colquhoun IJ, Parker ML, Plijter JJ, Shewry PR, Tatham AS, Wellner N. Effects of Temperature on Sorption of Water by Wheat Gluten Determined Using Deuterium Nuclear Magnetic Resonance. Cereal Chem 1999. [DOI: 10.1094/cchem.1999.76.2.219] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- A. Grant
- Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, Norwich, NR4 7UA, UK
- Corresponding author. Phone: +44(0) 1603 255000. Fax: +44(0)1603 507723. E-mail:
| | - P. S. Belton
- Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, Norwich, NR4 7UA, UK
| | - I. J. Colquhoun
- Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, Norwich, NR4 7UA, UK
| | - M. L. Parker
- Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, Norwich, NR4 7UA, UK
| | - J. J. Plijter
- Gist Brocades N.V., Research and Development, Wateringseweg 1, PO Box 1, 2600 MA, Delft, The Netherlands
| | - P. R. Shewry
- Department of Agricultural Sciences, University of Bristol, Institute of Arable Crops Research, Long Ashton Research Station, Bristol, BS18 9AF, UK
| | - A. S. Tatham
- Department of Agricultural Sciences, University of Bristol, Institute of Arable Crops Research, Long Ashton Research Station, Bristol, BS18 9AF, UK
| | - N. Wellner
- Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, Norwich, NR4 7UA, UK
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Kačuráková M, Wellner N, Ebringerová A, Hromádková Z, Wilson R, Belton P. Characterisation of xylan-type polysaccharides and associated cell wall components by FT-IR and FT-Raman spectroscopies. Food Hydrocoll 1999. [DOI: 10.1016/s0268-005x(98)00067-8] [Citation(s) in RCA: 211] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lacey DJ, Wellner N, Beaudoin F, Napier JA, Shewry PR. Secondary structure of oleosins in oil bodies isolated from seeds of safflower (Carthamus tinctorius L.) and sunflower (Helianthus annuus L.). Biochem J 1998; 334 ( Pt 2):469-77. [PMID: 9716507 PMCID: PMC1219711 DOI: 10.1042/bj3340469] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Oil bodies were isolated from mature seeds of sunflower (Helianthus annuus L.) and safflower (Carthamus tinctorius L.). Oil body preparations containing only oleosin proteins could be obtained from safflower seeds by salt-washing followed by centrifugation on discontinuous sucrose density gradients. However, it was necessary to treat sunflower oil bodies with urea to obtain preparations of similar purity. Incubation of the oil bodies with proteinases gave two fragments with molecular masses of 6 and 8 kDa which were protected from digestion. These fragments represented the hydrophobic domain of the oleosins, as determined by N-terminal sequencing. Intact and proteinase-treated oil bodies of both species were analysed by Fourier-transform infrared spectroscopy, as dry films and in aqueous medium, the spectra being compared with those obtained for pure oil samples in order to identify the bands resulting from the oleosin proteins and protected peptides. This investigation showed that the hydrophobic domain of the oleosins in intact oil bodies is predominantly alpha-helical in structure and that the conformation was not greatly affected by washing the oil bodies with urea during preparation.
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Affiliation(s)
- D J Lacey
- Institute of Arable Crops Research-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS41 9AF, UK
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Wellner N, Belton PS, Tatham AS. Fourier transform IR spectroscopic study of hydration-induced structure changes in the solid state of omega-gliadins. Biochem J 1996; 319 ( Pt 3):741-7. [PMID: 8920975 PMCID: PMC1217851 DOI: 10.1042/bj3190741] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The hydration of omega-gliadins and party deamidated and esterified omega-gliadins has been studied by Fourier transform IR spectroscopy. The secondary structure of the fully hydrated proteins was a mixture of beta-turns and extended chains, with a small amount of intermolecular beta-sheets. The absorption of the glutamine side chain amide groups contributed considerably to the amide I band with two well-defined peaks at 1658 and 1610 cm-1. the amide I band of the dry native sample could not be resolved into single component bands. There the backbone structure seemed to be distorted by extensive hydrogen bonding involving glutamine side chains. With increasing water content, these hydrogen bonds were broken successively by water molecules, resulting in an increase in extended, hydrated structures, which gave rise to the formation of intermolecular beta-sheet structures. Above 35% (w/w) water the beta-sheet content fell sharply and was replaced by extensively hydrated extended structures. An amide I band similar to dissolved poly-L-proline proved that parts of the polymer were in a solution-like state. The replacement of many glutamine side chains in the esterified protein produced more resolved secondary structures even in the dry sample. The beta-sheet content of the dry sample was higher than in the native omega-gliadins, but hydration generally caused very similar changes. At all hydration levels the spectra indicated a more ordered structure than in the native sample. Overall, the modification caused changes that go beyond the simple presence or absence of glutamine bands.
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Affiliation(s)
- N Wellner
- Institute of Food Research, Norwich Laboratory, Colney, U.K
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Belton PS, Colquhoun IJ, Grant A, Wellner N, Field JM, Shewry PR, Tatham AS. FTIR and NMR studies on the hydration of a high-M(r) subunit of glutenin. Int J Biol Macromol 1995; 17:74-80. [PMID: 7547718 DOI: 10.1016/0141-8130(95)93520-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The hydration behaviour of a purified high-M(r) subunit of glutenin has been studied using Fourier transform infra-red (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. The water-insoluble protein was examined in an unalkylated form with intermolecular disulfide bonds, and in a reduced and alkylated (unpolymerized) form. Hydration produced a marked increase in chain mobility, especially above a threshold water content of about 37% w/w. NMR experiments also showed that some parts of the chain were held in a much less mobile state, even at higher water contents. Little difference could be seen between alkylated and unalkylated subunits, implying that NMR is sensitive to localized motions, but not to any restrictions imposed by disulfide bridges close to the chain ends. FTIR spectra of the protein films have shown that increasing hydration enables changes to occur in favour of a more extended and beta-sheet-type structure. The changes in secondary structure are very noticeable at water contents corresponding to the NMR mobility threshold. The behaviour is influenced by intermolecular interactions. beta-sheet formation is enhanced by the presence of disulfide bonds in the unalkylated samples. There is little evidence of beta-structure (sheet or extended chain) either in the dry state, where protein-protein interactions are strongest, or in dilute acetic acid solution, where the interactions are weakest. The balance between protein-protein and protein-water hydrogen-bonding interactions therefore appears to influence the formation of beta-sheet and extended chain structures, and these may in turn affect the elasticity of high M(r) subunits.
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Affiliation(s)
- P S Belton
- Institute of Food Research, Norwich Laboratory, Colney, UK
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