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Fang YN, Rumyantsev AM, Neitzel AE, Liang H, Heller WT, Nealey PF, Tirrell MV, de Pablo JJ. Scattering evidence of positional charge correlations in polyelectrolyte complexes. Proc Natl Acad Sci U S A 2023; 120:e2302151120. [PMID: 37523553 PMCID: PMC10410704 DOI: 10.1073/pnas.2302151120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/30/2023] [Indexed: 08/02/2023] Open
Abstract
Polyelectrolyte complexation plays an important role in materials science and biology. The internal structure of the resultant polyelectrolyte complex (PEC) phase dictates properties such as physical state, response to external stimuli, and dynamics. Small-angle scattering experiments with X-rays and neutrons have revealed structural similarities between PECs and semidilute solutions of neutral polymers, where the total scattering function exhibits an Ornstein-Zernike form. In spite of consensus among different theoretical predictions, the existence of positional correlations between polyanion and polycation charges has not been confirmed experimentally. Here, we present small-angle neutron scattering profiles where the polycation scattering length density is matched to that of the solvent to extract positional correlations among anionic monomers. The polyanion scattering functions exhibit a peak at the inverse polymer screening radius of Coulomb interactions, q* ≈ 0.2 Å-1. This peak, attributed to Coulomb repulsions between the fragments of polyanions and their attractions to polycations, is even more pronounced in the calculated charge scattering function that quantifies positional correlations of all polymer charges within the PEC. Screening of electrostatic interactions by adding salt leads to the gradual disappearance of this correlation peak, and the scattering functions regain an Ornstein-Zernike form. Experimental scattering results are consistent with those calculated from the random phase approximation, a scaling analysis, and molecular simulations.
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Affiliation(s)
- Yan N. Fang
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, IL60439
| | - Artem M. Rumyantsev
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC27695
| | - Angelika E. Neitzel
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, IL60439
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL32611
| | - Heyi Liang
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
| | - William T. Heller
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN37831
| | - Paul F. Nealey
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, IL60439
| | - Matthew V. Tirrell
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, IL60439
| | - Juan J. de Pablo
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL60637
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, IL60439
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2
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Damont A, Legrand A, Cao C, Fenaille F, Tabet JC. Hydrogen/deuterium exchange mass spectrometry in the world of small molecules. Mass Spectrom Rev 2023; 42:1300-1331. [PMID: 34859466 DOI: 10.1002/mas.21765] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 06/07/2023]
Abstract
The combined use of hydrogen/deuterium exchange (HDX) and mass spectrometry (MS), referred to as HDX-MS, is a powerful tool for exploring molecular edifices and has been used for over 60 years. Initially for structural and mechanistic investigation of low-molecular weight organic compounds, then to study protein structure and dynamics, then, the craze to study small molecules by HDX-MS accelerated and has not stopped yet. The purpose of this review is to present its different facets with particular emphasis on recent developments and applications. Reversible H/D exchanges of mobilizable protons as well as stable exchanges of non-labile hydrogen are considered whether they are taking place in solution or in the gas phase, or enzymatically in a biological media. Some fundamental principles are restated, especially for gas-phase processes, and an overview of recent applications, ranging from identification to quantification through the study of metabolic pathways, is given.
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Affiliation(s)
- Annelaure Damont
- Département Médicaments et Technologies pour la Santé (DMTS), MetaboHUB, Université Paris-Saclay, CEA, INRAE, Gif-sur-Yvette, France
| | - Anaïs Legrand
- Département Médicaments et Technologies pour la Santé (DMTS), MetaboHUB, Université Paris-Saclay, CEA, INRAE, Gif-sur-Yvette, France
| | - Chenqin Cao
- Département Médicaments et Technologies pour la Santé (DMTS), MetaboHUB, Université Paris-Saclay, CEA, INRAE, Gif-sur-Yvette, France
| | - François Fenaille
- Département Médicaments et Technologies pour la Santé (DMTS), MetaboHUB, Université Paris-Saclay, CEA, INRAE, Gif-sur-Yvette, France
| | - Jean-Claude Tabet
- Département Médicaments et Technologies pour la Santé (DMTS), MetaboHUB, Université Paris-Saclay, CEA, INRAE, Gif-sur-Yvette, France
- Faculté des Sciences et de l'Ingénierie, Institut Parisien de Chimie Moléculaire (IPCM), Sorbonne Université, Paris, France
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3
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Niess F, Hingerl L, Strasser B, Bednarik P, Goranovic D, Niess E, Hangel G, Krššák M, Spurny-Dworak B, Scherer T, Lanzenberger R, Bogner W. Noninvasive 3-Dimensional 1 H-Magnetic Resonance Spectroscopic Imaging of Human Brain Glucose and Neurotransmitter Metabolism Using Deuterium Labeling at 3T : Feasibility and Interscanner Reproducibility. Invest Radiol 2023; 58:431-437. [PMID: 36735486 PMCID: PMC10184811 DOI: 10.1097/rli.0000000000000953] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/15/2022] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Noninvasive, affordable, and reliable mapping of brain glucose metabolism is of critical interest for clinical research and routine application as metabolic impairment is linked to numerous pathologies, for example, cancer, dementia, and depression. A novel approach to map glucose metabolism noninvasively in the human brain has been presented recently on ultrahigh-field magnetic resonance (MR) scanners (≥7T) using indirect detection of deuterium-labeled glucose and downstream metabolites such as glutamate, glutamine, and lactate. The aim of this study was to demonstrate the feasibility to noninvasively detect deuterium-labeled downstream glucose metabolites indirectly in the human brain via 3-dimensional (3D) proton ( 1 H) MR spectroscopic imaging on a clinical 3T MR scanner without additional hardware. MATERIALS AND METHODS This prospective, institutional review board-approved study was performed in 7 healthy volunteers (mean age, 31 ± 4 years, 5 men/2 women) after obtaining written informed consent. After overnight fasting and oral deuterium-labeled glucose administration, 3D metabolic maps were acquired every ∼4 minutes with ∼0.24 mL isotropic spatial resolution using real-time motion-, shim-, and frequency-corrected echo-less 3D 1 H-MR spectroscopic Imaging on a clinical routine 3T MR system. To test the interscanner reproducibility of the method, subjects were remeasured on a similar 3T MR system. Time courses were analyzed using linear regression and nonparametric statistical tests. Deuterium-labeled glucose and downstream metabolites were detected indirectly via their respective signal decrease in dynamic 1 H MR spectra due to exchange of labeled and unlabeled molecules. RESULTS Sixty-five minutes after deuterium-labeled glucose administration, glutamate + glutamine (Glx) signal intensities decreased in gray/white matter (GM/WM) by -1.63 ± 0.3/-1.0 ± 0.3 mM (-13% ± 3%, P = 0.02/-11% ± 3%, P = 0.02), respectively. A moderate to strong negative correlation between Glx and time was observed in GM/WM ( r = -0.64, P < 0.001/ r = -0.54, P < 0.001), with 60% ± 18% ( P = 0.02) steeper slopes in GM versus WM, indicating faster metabolic activity. Other nonlabeled metabolites showed no significant changes. Excellent intrasubject repeatability was observed across scanners for static results at the beginning of the measurement (coefficient of variation 4% ± 4%), whereas differences were observed in individual Glx dynamics, presumably owing to physiological variation of glucose metabolism. CONCLUSION Our approach translates deuterium metabolic imaging to widely available clinical routine MR scanners without specialized hardware, offering a safe, affordable, and versatile (other substances than glucose can be labeled) approach for noninvasive imaging of glucose and neurotransmitter metabolism in the human brain.
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Affiliation(s)
- Fabian Niess
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Lukas Hingerl
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Bernhard Strasser
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Petr Bednarik
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, University Hospital Amager and Hvidovre, Hvidovre, Denmark
- Department of Radiology, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark
| | - Dario Goranovic
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Eva Niess
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Gilbert Hangel
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
- Department of Neurosurgery
| | - Martin Krššák
- Department of Medicine III, Division of Endocrinology and Metabolism
| | - Benjamin Spurny-Dworak
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Vienna, Austria
| | - Thomas Scherer
- Department of Medicine III, Division of Endocrinology and Metabolism
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Vienna, Austria
| | - Wolfgang Bogner
- From the High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
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Abstract
Small-angle neutron scattering (SANS) is a powerful tool for studying biological membranes and model lipid bilayer membranes. The length scales probed by SANS, being from 1 nm to over 100 nm, are well-matched to the relevant length scales of the bilayer, particularly when it is in the form of a vesicle. However, it is the ability of SANS to differentiate between isotopes of hydrogen as well as the availability of deuterium labeled lipids that truly enable SANS to reveal details of membranes that are not accessible with the use of other techniques, such as small-angle X-ray scattering. In this work, an overview of the use of SANS for studying unilamellar lipid bilayer vesicles is presented. The technique is briefly presented, and the power of selective deuteration and contrast variation methods is discussed. Approaches to modeling SANS data from unilamellar lipid bilayer vesicles are presented. Finally, recent examples are discussed. While the emphasis is on studies of unilamellar vesicles, examples of the use of SANS to study intact cells are also presented.
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Affiliation(s)
- William T Heller
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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5
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Larson EA, Rensner JJ, Larsen KR, Bellaire B, Lee YJ. Rapid Antibiotic Susceptibility Testing by Deuterium Labeling of Bacterial Lipids in On-Target Microdroplet Cultures. J Am Soc Mass Spectrom 2022; 33:1221-1228. [PMID: 35623100 PMCID: PMC9264383 DOI: 10.1021/jasms.2c00056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Antimicrobial resistance is a serious challenge facing human and veterinary health. Current methods of detecting resistance are limited in turn-around time or universal detection. In this work, a new antimicrobial susceptibility test is developed and validated, which utilizes deuterium labeling of membrane lipids to track the growth of bacterial cells. We hypothesize that deuterium uptake and subsequent labeling of lipids can be detected using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Additionally, bacteria growth is performed on the MALDI target, minimizing sample preparation materials and time. When two Escherichia coli strains are grown in the presence of deuterium oxide, labeling can be detected in as little as 30 min to 2 h. The labeling efficiency, or the ratio of labeled to unlabeled lipid peaks, provides information about the growth rate of bacteria. This growth ratio can differentiate between resistant and susceptible strains of bacteria as a resistant strain will maintain ∼50% labeling efficiency between untreated and treated cultures. In comparison, a susceptible strain will see a decrease in fractional abundance of deuterium from ∼50% in the untreated to ∼10% in the treated. This approach is applied to measure the minimum inhibitory concentration (MIC) of the resistant and susceptible strains from on-target microdroplet culture in a range of antibiotic concentrations. The first antibiotic concentration with a significant decrease in fractional abundance of deuterium correlates well with a traditionally obtained MIC using broth dilution, indicating the clinical relevance of the results.
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Affiliation(s)
- Evan A. Larson
- Department
of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Josiah J. Rensner
- Department
of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Kristina R. Larsen
- Department
of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, Iowa 50011, United States
| | - Bryan Bellaire
- Department
of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, Iowa 50011, United States
| | - Young Jin Lee
- Department
of Chemistry, Iowa State University, Ames, Iowa 50011, United States
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6
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Sancéau JY, Bélanger P, Maltais R, Poirier D. An Improved Synthesis of Glucuronide Metabolites of Hindered Phenolic Xenoestrogens. Curr Org Synth 2022; 19:838-845. [PMID: 35473530 DOI: 10.2174/1570179419666220426104848] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 02/18/2022] [Accepted: 03/08/2022] [Indexed: 11/22/2022]
Abstract
AIM AND OBJECTIVE The syntheses of glucuronide metabolites of phenolic xenoestrogens triclosan and 2-phenylphenol, namely triclosan-O-glucuronide (TCS-G; 1), and 2-phenylphenol-O-glucuronide (OPP-G; 2), were achieved for use as analytical standards. METHODS Under classical conditions previously reported for glucuronide synthesis, the final basic hydrolysis of the peracylated ester intermediate leading to the free glucuronides is often a limiting step. Indeed, the presence of contaminating by-products resulting from ester elimination has often been observed during this step. This is particularly relevant when the sugar unit is close to a crowded environment as for triclosan and 2-phenylphenol. RESULTS To circumvent these problems, we proposed mild conditions for the deprotection of peracetylated glucuronate intermediates. CONCLUSION A new methodology using a key imidate following a two-step saponification protocol for acetates and methyl ester hydrolysis was successfully applied to the preparation of TCS-d3 (1) and OPP-G (2) as well as deuterated isotopomers TCS-d3-G (1-d3) and OPP-d5-G (2-d5).
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Affiliation(s)
- Jean-Yves Sancéau
- Organic Synthesis Service, Medicinal Chemistry Platform, Centre Hospitalier Universitaire (CHU) de Québec-Research Center, Québec, QC, G1V 4G2, Canada
| | - Patrick Bélanger
- Laboratoire du Centre de Toxicologie (CTQ), Institut national de santé publique du Québec (INSPQ), Québec, QC, G1V 5B3, Canada
| | - René Maltais
- Organic Synthesis Service, Medicinal Chemistry Platform, Centre Hospitalier Universitaire (CHU) de Québec-Research Center, Québec, QC, G1V 4G2, Canada
| | - Donald Poirier
- Organic Synthesis Service, Medicinal Chemistry Platform, Centre Hospitalier Universitaire (CHU) de Québec-Research Center, Québec, QC, G1V 4G2, Canada.,Laboratoire du Centre de Toxicologie (CTQ), Institut national de santé publique du Québec (INSPQ), Québec, QC, G1V 5B3, Canada
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7
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Kobak KA, Batushansky A, Borowik AK, Lopes EPB, Peelor III FF, Donovan EL, Kinter MT, Miller BF, Griffin TM. An In Vivo Stable Isotope Labeling Method to Investigate Individual Matrix Protein Synthesis, Ribosomal Biogenesis, and Cellular Proliferation in Murine Articular Cartilage. Function (Oxf) 2022; 3:zqac008. [PMID: 35399495 PMCID: PMC8991031 DOI: 10.1093/function/zqac008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/28/2022] [Accepted: 02/17/2022] [Indexed: 02/04/2023]
Abstract
Targeting chondrocyte dynamics is a strategy for slowing osteoarthritis progression during aging. We describe a stable-isotope method using in vivo deuterium oxide labeling and mass spectrometry to measure protein concentration, protein half-life, cell proliferation, and ribosomal biogenesis in a single sample of murine articular cartilage. We hypothesized that a 60-d labeling period would capture age-related declines in cartilage matrix protein content, protein synthesis rates, and cellular proliferation. Knee cartilage was harvested to the subchondral bone from 25- to 90-wk-old female C57BL/6J mice treated with deuterium oxide for 15, 30, 45, and 60 d. We measured protein concentration and half-lives using targeted high resolution accurate mass spectrometry and d2ome data processing software. Deuterium enrichment was quantified in isolated DNA and RNA to measure cell proliferation and ribosomal biogenesis, respectively. Most collagen isoforms were less abundant in aged animals, with negligible collagen synthesis at either age. In contrast, age altered the concentration and half-lives of many proteoglycans and other matrix proteins, including several with greater concentration and half-lives in older mice such as proteoglycan 4, clusterin, and fibronectin-1. Cellular proteins were less abundant in older animals, consistent with reduced cellularity. Nevertheless, deuterium was maximally incorporated into 60% of DNA and RNA by 15 d of labeling in both age groups, suggesting the presence of two large pools of either rapidly (<15 d) or slowly (>60 d) proliferating cells. Our findings indicate that age-associated changes in cartilage matrix protein content and synthesis occur without detectable changes in the relative number of proliferating cells.
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Affiliation(s)
- Kamil A Kobak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA,Institute of Heart Diseases, Wroclaw Medical University, Wroclaw 50-367, Poland
| | | | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Erika Prado Barboza Lopes
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Frederick F Peelor III
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | | | - Michael T Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
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Shirakawa A, Manabe Y, Marchetti R, Yano K, Masui S, Silipo A, Molinaro A, Fukase K. Chemical Synthesis of Sialyl N-Glycans and Analysis of Their Recognition by Neuraminidase. Angew Chem Int Ed Engl 2021; 60:24686-24693. [PMID: 34520098 DOI: 10.1002/anie.202111035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Indexed: 11/07/2022]
Abstract
The chemical synthesis of a fully sialylated tetraantennary N-glycan has been achieved for the first time by using the diacetyl strategy, in which NHAc is protected as NAc2 to improve reactivity by preventing intermolecular hydrogen bonds. Another key was the glycosylation to the branched mannose in an ether solvent, which promoted the desired glycosylation by stabilizing the oxocarbenium ion intermediate. Furthermore, high α-selectivity of these glycosylation reactions was realized by utilizing remote participation. Two asymmetrically deuterium labeled sialyl N-glycans were also synthesized by the same strategy. The synthesized N-glycans were used to probe the molecular basis of H1N1 neuraminidase recognition. The asymmetrically deuterated N-glycans revealed a difference in the recognition of sialic acid on each branch. Meanwhile, the tetraantennary N-glycan was used to evaluate the effects of multivalency and steric hinderance by forming branching structures.
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Affiliation(s)
- Asuka Shirakawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Yoshiyuki Manabe
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Roberta Marchetti
- Department of Chemical Science, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy
| | - Kumpei Yano
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Seiji Masui
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Alba Silipo
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Department of Chemical Science, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy
| | - Antonio Molinaro
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Department of Chemical Science, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy
| | - Koichi Fukase
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
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9
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Sakakibara Y, Osada K, Uraki Y, Ubukata M, Shigetomi K. Direct deuteration of hinokitiol and its mechanistic study. Biosci Biotechnol Biochem 2021; 85:215-222. [PMID: 33590006 DOI: 10.1093/bbb/zbaa031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 09/05/2020] [Indexed: 11/14/2022]
Abstract
Hinokitiol has a broad antibacterial activity against bacteria and fungi. While its biosynthetic pathway has been intensively studied, its dynamics in natural environments, such as biodegradation pathway, remain unclear. In this study, the authors report a direct deuterium labeling of hinokitiol as a traceable molecular probe to serve those studies. Hinokitiol was subjected to the H2-Pd/C-D2O conditions and deuterated hinokitiol was obtained with excellent deuteration efficiencies and in moderate yield. The 1H and 2H NMR spectra indicated that all ring- and aliphatic hydrogens except that on C-6 were substituted by deuterium. According to the substrate scope and computational chemistry, deuteration on tropolone ring was suggested to proceed via D+-mediated process, and which was supported by the results of the experiment with trifluoroacetic acid and Pd(TPP)4. On the other hand, the deuteration on aliphatic group was predicted to be catalyzed by Pd(II) species.
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Affiliation(s)
| | - Kota Osada
- School of Agriculture, Hokkaido University, Sapporo, Japan
| | - Yasumitsu Uraki
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Makoto Ubukata
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Kengo Shigetomi
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
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10
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Baliu-Piqué M, van Hoeven V, Drylewicz J, van der Wagen LE, Janssen A, Otto SA, van Zelm MC, de Boer RJ, Kuball J, Borghans JA, Tesselaar K. Cell-density independent increased lymphocyte production and loss rates post-autologous HSCT. eLife 2021; 10:59775. [PMID: 33538246 PMCID: PMC7886352 DOI: 10.7554/elife.59775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 02/03/2021] [Indexed: 12/18/2022] Open
Abstract
Lymphocyte numbers need to be quite tightly regulated. It is generally assumed that lymphocyte production and lifespan increase homeostatically when lymphocyte numbers are low and, vice versa, return to normal once cell numbers have normalized. This widely accepted concept is largely based on experiments in mice, but is hardly investigated in vivo in humans. Here we quantified lymphocyte production and loss rates in vivo in patients 0.5–1 year after their autologous hematopoietic stem cell transplantation (autoHSCT). We indeed found that the production rates of most T- and B-cell subsets in autoHSCT-patients were two to eight times higher than in healthy controls, but went hand in hand with a threefold to ninefold increase in cell loss rates. Both rates also did not normalize when cell numbers did. This shows that increased lymphocyte production and loss rates occur even long after autoHSCT and can persist in the face of apparently normal cell numbers.
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Affiliation(s)
- Mariona Baliu-Piqué
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Vera van Hoeven
- Department of Experimental Immunology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Julia Drylewicz
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | | | - Anke Janssen
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Sigrid A Otto
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Menno C van Zelm
- Department of Immunology and Pathology, Monash University and Alfred Hospital, Melbourne, Australia
| | - Rob J de Boer
- Theoretical Biology, Utrecht University, Utrecht, Netherlands
| | - Jürgen Kuball
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands.,Department of Hematology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Jose Am Borghans
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Kiki Tesselaar
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
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11
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Abstract
α-2H amino acids are valuable precursors toward labeled pharmaceutical agents and tools for studying biological systems; however, these molecules are costly to purchase and challenging to synthesize in a site- and stereoselective manner. Here, we show that an α-oxo-amine synthase that evolved for saxitoxin biosynthesis, SxtA AONS, is capable of producing a range of α-2H amino acids and esters site- and stereoselectively using D2O as the deuterium source. Additionally, we demonstrate the utility of this operationally simple reaction on preparative scale in the stereoselective chemoenzymatic synthesis of a deuterated analog of safinamide, a drug used to treat Parkinson's disease.
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12
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Morris-Paterson TE, Stimpson SA, Miller RR, Barton ME, Leonard MS, Carmichael O, van Someren KA, Harridge SDR. Total body skeletal muscle mass estimated by magnetic resonance imaging and creatine (methyl-d 3 ) dilution in athletes. Scand J Med Sci Sports 2019; 30:421-428. [PMID: 31715651 DOI: 10.1111/sms.13585] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 10/15/2019] [Accepted: 10/21/2019] [Indexed: 01/07/2023]
Abstract
Creatine dilution (D3 -cr) is a technique for estimating total skeletal muscle mass (SMM) with practical utility, but has not been applied in athletic populations where body composition may differ to that in the normal population. This study aimed to assess the agreement between SMM derived from both D3 -cr and that obtained from whole-body magnetic resonance imaging (MRI) in 15 male and 5 female national level kayakers (stature: 182.0 ± 13.1 and 170.0 ± 9.0 cm; body mass: 80.6 ± 9.9 and 66.4 ± 6.0 kg; V̇O2 peak: 56.5 ± 7.0 and 49.6 ± 4.4 mL kg-1 min-1 , mean ± SD). SMM was determined following 60 mg of dosed D3 -cr and analysis of expelled urine collected on four subsequent days for creatine, creatinine, D3 -cr, and D3 -creatinine using liquid chromatography/mass spectroscopy. SMM was then estimated by assuming a creatine pool size of 4.3 g/kg. During the same time period, a whole-body MRI was undertaken to derive SMM from the analysis of multiple slices taken across the body. A strong positive correlation (F = 74.32; R = 0.90; P < .0001) between the two methods was observed, but the D3 -cr SMM was found to be significantly higher (43.3 ± 6.8 kg) when compared with MRI (36.3 ± 5.8 kg, P < .0001). However, the difference between the methods was removed when a higher intramuscular creatine pool (5.1 g/kg) was assumed. These data show that D3 -cr has potential utility in athletes, as referenced against MRI, but show that assumptions regarding creatine pool size need to be carefully considered.
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Affiliation(s)
- Tessa E Morris-Paterson
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Stephen A Stimpson
- Muscle Metabolism Discovery Performance Unit, GSK, Research Triangle Park, NC, USA
| | - Ram R Miller
- Muscle Metabolism Discovery Performance Unit, GSK, Research Triangle Park, NC, USA.,Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Matthew E Barton
- Muscle Metabolism Discovery Performance Unit, GSK, Research Triangle Park, NC, USA.,Global Clinical Development, Gan & Lee Pharmaceuticals USA Corporation, Bridgewater, NJ, USA
| | - Michael S Leonard
- Muscle Metabolism Discovery Performance Unit, GSK, Research Triangle Park, NC, USA.,United Therapeutics, Research Triangle Park, NC, USA
| | - Owen Carmichael
- Biomedical Imaging Center, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | | | - Stephen D R Harridge
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
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13
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Könen PP, Wüst M. Analysis of sesquiterpene hydrocarbons in grape berry exocarp ( Vitis vinifera L.) using in vivo-labeling and comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS). Beilstein J Org Chem 2019; 15:1945-1961. [PMID: 31501661 PMCID: PMC6720654 DOI: 10.3762/bjoc.15.190] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/02/2019] [Indexed: 12/11/2022] Open
Abstract
Sesquiterpenes are structurally diverse, potent flavoring substances that significantly influence the aroma profile of grapes (Vitis vinifera L.) at the time of physiological ripening. To investigate these natural compounds, freshly harvested, ripe berries of the red wine variety Lemberger (Vitis vinifera subsp. vinifera L.) were analyzed using comprehensive two-dimensional gas chromatography (GC×GC) coupled to a time-of-flight mass spectrometer (TOF–MS) after headspace-solid phase microextraction (HS-SPME). The identification of structurally complex natural compounds, such as sesquiterpenes from fruits and vegetables, is often reported as “tentative”, as authentic standards are not commercially available for most of the analytes. For this reason, feeding experiments (in vivo labeling) were carried out using the stable isotope-labeled precursors [5,5-2H2]-1-deoxy-ᴅ-xylulose (d2-DOX) and [6,6,6-2H3]-(±)-mevalonolactone (d3-MVL) to clearly identify the volatiles. Based on the recorded mass spectra of the unlabeled and deuterated compounds, mechanisms for sesquiterpene formation in V. vinifera could be proposed and already known pathways could be confirmed or disproved. For example, the HS-SPME–GC×GC–TOF–MS measurements of fed sample material showed that the tricyclic sesquiterpene hydrocarbons α-copaene, β-copaene, α-cubebene, β-cubebene and the bicyclic δ-cadinene were biosynthesized via (S)-(−)-germacrene D rather than via (R)-(+)-germacrene D as intermediate.
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Affiliation(s)
- Philipp P Könen
- Institute of Nutritional and Food Sciences, Chair of Food Chemistry, University of Bonn, Endenicher Allee 19C, 53115 Bonn, Germany
| | - Matthias Wüst
- Institute of Nutritional and Food Sciences, Chair of Food Chemistry, University of Bonn, Endenicher Allee 19C, 53115 Bonn, Germany
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14
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Sheveleva NN, Markelov DA, Vovk MA, Tarasenko II, Mikhailova ME, Ilyash MY, Neelov IM, Lahderanta E. Stable Deuterium Labeling of Histidine-Rich Lysine-Based Dendrimers. Molecules 2019; 24:E2481. [PMID: 31284551 PMCID: PMC6651089 DOI: 10.3390/molecules24132481] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [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: 06/15/2019] [Revised: 07/02/2019] [Accepted: 07/04/2019] [Indexed: 01/02/2023] Open
Abstract
Peptide dendrimers, due to their biocompatibility and low toxicity, are highly promising candidates as nanocarriers for drugs and genes. The development of this kind of delivery system requires reliable monitoring of their metabolic and biological pathways. In this respect, hydrogen isotope labeling has tremendous importance, being a safe tool for detection of the labeled nanocarriers. In this work, we have synthesized new histidine-rich lysine-based dendrimers (Lys-2His dendrimer) with two linear histidine (His) residues in every inner segment. The presence of His residues has enabled us to perform controlled deuteration of Lys-2His dendrimers. The high deuteration degree (around 70%) does not practically change after redissolving the samples in H2O and heating them at 40 °C, which indicates the isotopic label stability.
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Affiliation(s)
- Nadezhda N Sheveleva
- Saint Petersburg State University, 7/9 Universitetskaya nab, 199034 Saint Petersburg, Russia
| | - Denis A Markelov
- Saint Petersburg State University, 7/9 Universitetskaya nab, 199034 Saint Petersburg, Russia.
| | - Mikhail A Vovk
- Saint Petersburg State University, 7/9 Universitetskaya nab, 199034 Saint Petersburg, Russia
| | - Irina I Tarasenko
- Institute of Macromolecular Compounds, Russian Academy of Sciences, Bolshoi Prospect 31, V.O., 199004 Saint Petersburg, Russia
| | - Mariya E Mikhailova
- Saint Petersburg State University, 7/9 Universitetskaya nab, 199034 Saint Petersburg, Russia
| | - Maxim Yu Ilyash
- Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University), Kronverkskiy pr. 49, 197101 Saint Petersburg, Russia
| | - Igor M Neelov
- Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University), Kronverkskiy pr. 49, 197101 Saint Petersburg, Russia
| | - Erkki Lahderanta
- Department of Physics, LUT University, Box 20, 53851 Lappeenranta, Finland
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15
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Borghans JAM, Tesselaar K, de Boer RJ. Current best estimates for the average lifespans of mouse and human leukocytes: reviewing two decades of deuterium-labeling experiments. Immunol Rev 2019; 285:233-248. [PMID: 30129193 DOI: 10.1111/imr.12693] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Deuterium is a non-toxic, stable isotope that can safely be administered to humans and mice to study their cellular turnover rates in vivo. It is incorporated into newly synthesized DNA strands during cell division, without interference with the kinetics of cells, and the accumulation and loss of deuterium in the DNA of sorted (sub-)populations of leukocytes can be used to estimate their cellular production rates and lifespans. In the past two decades, this powerful technology has been used to estimate the turnover rates of various types of leukocytes. Although it is the most reliable technique currently available to study leukocyte turnover, there are remarkable differences between the cellular turnover rates estimated by some of these studies. We have recently established that part of this variation is due to (a) difficulties in estimating deuterium availability in some deuterium-labeling studies, and (b) assumptions made by the mathematical models employed to fit the data. Being aware of these two problems, we here aim to approach a consensus on the life expectancies of different types of T cells, B cells, monocytes, and neutrophils in mice and men. We address remaining outstanding problems whenever appropriate and discuss for which immune subpopulations we currently have too little information to draw firm conclusions about their turnover.
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Affiliation(s)
- José A M Borghans
- Laboratory of Translational Immunology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Kiki Tesselaar
- Laboratory of Translational Immunology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Rob J de Boer
- Theoretical Biology & Bioinformatics, Utrecht, The Netherlands
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16
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Bolla RS, Gandikota NM, Kasi Viswanath IV. Synthesis of Deuterium Labeled 5, 5-Dimethyl-3-(α, α, α-trifluoro-4-nitro-m-tolyl) Hydantoin. Curr Radiopharm 2019; 12:82-87. [PMID: 30854946 DOI: 10.2174/1874471012666181130162731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 10/25/2018] [Accepted: 11/05/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Stable and non-radioactive isotope labeled compounds gained significance in recent drug discovery and other various applications such as bio-analytical studies. The modern bioanalytical techniques can study the adverse therapeutic effects of drugs by comparing isotopically labeled internal standards. A well-designed labeled compound can provide high-quality information about the identity and quantification of drug-related compounds in biological samples. This information can be very useful at key decision points in drug development. In this study, we tried to synthesize Nilutamide- d6 which can be useful to study the adverse effects of Nilutamide, and based on these can modify or widen the new drug derivatives. Nilutamide is a nonsteroidal antiandrogen which is used in the treatment of prostate cancer. The aim of this study was to develop a synthetic approach to prepare deuterium labeled [2H6]-5, 5-dimethylimidazolidine-2, 4-dione and [2H6]-nilutamide. METHODS Since nilutamide is a derivative of hydantoin, it involves the synthesis of Dimethylhydantoin via Bucherer-Bergs hydantoin synthesis, followed by oxidative N-arylation with 4-iodo-1-nitro-2- (trifluoromethyl) benzene. CONCLUSION We successfully synthesized [2H6]-nilutamide and [2H6]-dimethylhydantoin with good isotopic purity, measured to be of adequate quality for use as internal standards in bio-analytical studies. A brief mechanistic study of Bucherer-Bergs hydantoin reaction was carried and the reason for possible H/D exchange was explained.
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Affiliation(s)
- Ratna Sekhar Bolla
- Department of Chemistry, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur Dist 522502, India
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17
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Xia HM, Zhang FL, Ye T, Wang YF. Selective α-Monomethylation by an Amine-Borane/N,N-Dimethylformamide System as the Methyl Source. Angew Chem Int Ed Engl 2018; 57:11770-11775. [PMID: 29968283 DOI: 10.1002/anie.201804794] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Indexed: 12/13/2022]
Abstract
A new and practical α-monomethylation strategy using an amine-borane/N,N-dimethylformamide (R3 N-BH3 /DMF) system as the methyl source was developed. This protocol has been found to be effective in the α-monomethylation of arylacetonitriles and arylacetamides. Mechanistic studies revealed that the formyl group of DMF delivered the carbon and one hydrogen atoms of the methyl group, and R3 N-BH3 donated the remaining two hydrogen atoms. Such a unique reaction pathway enabled controllable assemblies of CDH2 -, CD2 H-, and CD3 - units using Me2 NH-BH3 /d7 -DMF, Me3 N-BD3 /DMF and Me3 N-BD3 /d7 -DMF systems, respectively. Further application of this method to the facile synthesis of anti-inflammatory flurbiprofen and its varied deuterium-labeled derivatives was demonstrated.
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Affiliation(s)
- Hui-Min Xia
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, and, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Feng-Lian Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, and, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Tian Ye
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, and, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Yi-Feng Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, and, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China.,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, China
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18
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Liu B, Qin H, Zhang Y. An efficient and facile synthesis of deuterium-labeled anticancer agent bendamustine hydrochloride. J Labelled Comp Radiopharm 2018; 61:869-874. [PMID: 29770488 DOI: 10.1002/jlcr.3637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 04/11/2018] [Accepted: 05/02/2018] [Indexed: 11/11/2022]
Abstract
Bendamustine hydrochloride is an alkylating agent that was developed for the treatment of various human cancers. The stable isotope-labeled bendamustine was required to support clinic studies. An effective and operationally simple method for the synthesis of [D6 ] bendamustine hydrochloride was developed using DCl as a catalyst and D2 O as a deuterium source. Under the present condition, regioselectively deuterated bendamustine hydrochloride with high deuterium incorporation is achieved.
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Affiliation(s)
- Baomin Liu
- Jiangsu Key Laboratory of Targeted Antiviral Research, Chia Tai Tianqing Pharmaceutical Group Co., LTD, Nanjing, Jiangsu Province, China
| | - Hui Qin
- Jiangsu Key Laboratory of Targeted Antiviral Research, Chia Tai Tianqing Pharmaceutical Group Co., LTD, Nanjing, Jiangsu Province, China
| | - Yinsheng Zhang
- Jiangsu Key Laboratory of Targeted Antiviral Research, Chia Tai Tianqing Pharmaceutical Group Co., LTD, Nanjing, Jiangsu Province, China
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19
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Nishida Y, Yuan M, Fukuda K, Fujisawa K, Dohi H, Uzawa H. Remarkable functions of sn-3 hydroxy and phosphocholine groups in 1,2-diacyl- sn-glycerolipids to induce clockwise (+)-helicity around the 1,2-diacyl moiety: Evidence from conformation analysis by 1H NMR spectroscopy. Beilstein J Org Chem 2017; 13:1999-2009. [PMID: 29062420 PMCID: PMC5629397 DOI: 10.3762/bjoc.13.196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 09/01/2017] [Indexed: 01/31/2023] Open
Abstract
Cell-membrane glycerolipids exhibit a common structural backbone of asymmetric 1,2-diacyl-sn-glycerol bearing polar head groups in the sn-3 position. In this study, the possible effects of sn-3 head groups on the helical conformational property around the 1,2-diacyl moiety in the solution state were examined. 1H NMR Karplus relation studies were carried out using a series of 1,2-dipalmitoyl-sn-glycerols bearing different sn-3 substituents (namely palmitoyl, benzyl, hydrogen, and phosphates). The 1H NMR analysis indicated that the helical property around the 1,2-diacyl moiety is considerably affected by these sn-3 substituents. The sn-3 hydroxy group induced a unique helical property, which was considerably dependent on the solvents used. In CDCl3 solution, three staggered conformers, namely gt(+), gg(−) and tg, were randomized, while in more polar solvents, the gt(+) conformer with (+)-helicity was amplified at the expense of gg(−) and tg conformers. The sn-3 phosphocholine in phosphatidylcholine exhibited a greater effect on the gt(+) conformer, which was independent of the solvents used. From the 1H NMR analysis, the helical conformational properties around the 1,2-diacyl moiety conformed to a simple empirical rule, which permitted the proposal of a conformational diagram for 1,2-dipalmitoyl-sn-glycerols in the solution states.
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Affiliation(s)
- Yoshihiro Nishida
- Nanobiology Course in Graduate School of Advanced Integration Science & Molecular Chirality Research Center, Chiba University, Matsudo 271-8510, Chiba, Japan
| | - Mengfei Yuan
- Nanobiology Course in Graduate School of Advanced Integration Science & Molecular Chirality Research Center, Chiba University, Matsudo 271-8510, Chiba, Japan
| | - Kazuo Fukuda
- Nanobiology Course in Graduate School of Advanced Integration Science & Molecular Chirality Research Center, Chiba University, Matsudo 271-8510, Chiba, Japan
| | - Kaito Fujisawa
- Nanobiology Course in Graduate School of Advanced Integration Science & Molecular Chirality Research Center, Chiba University, Matsudo 271-8510, Chiba, Japan
| | - Hirofumi Dohi
- Nanobiology Course in Graduate School of Advanced Integration Science & Molecular Chirality Research Center, Chiba University, Matsudo 271-8510, Chiba, Japan
| | - Hirotaka Uzawa
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8565, Japan
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20
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Abstract
Raman-based optical imaging is a promising analytical tool for noninvasive, label-free chemical imaging of lipid bilayers and cellular membranes. Imaging using spontaneous Raman scattering suffers from a low intensity that hinders its use in some cellular applications. However, developments in coherent Raman imaging, surface-enhanced Raman imaging, and tip-enhanced Raman imaging have enabled video-rate imaging, excellent detection limits, and nanometer spatial resolution, respectively. After a brief introduction to these commonly used Raman imaging techniques for cell membrane studies, this review discusses selected applications of these modalities for chemical imaging of membrane proteins and lipids. Finally, recent developments in chemical tags for Raman imaging and their applications in the analysis of selected cell membrane components are summarized. Ongoing developments toward improving the temporal and spatial resolution of Raman imaging and small-molecule tags with strong Raman scattering cross sections continue to expand the utility of Raman imaging for diverse cell membrane studies.
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Affiliation(s)
- Aleem Syed
- Department of Chemistry, Iowa State University, Ames, Iowa 50011; ,
- Ames Laboratory, US Department of Energy, Ames, Iowa 50011
| | - Emily A Smith
- Department of Chemistry, Iowa State University, Ames, Iowa 50011; ,
- Ames Laboratory, US Department of Energy, Ames, Iowa 50011
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21
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Lahoz-Beneytez J, Schaller S, Macallan D, Eissing T, Niederalt C, Asquith B. Physiologically Based Simulations of Deuterated Glucose for Quantifying Cell Turnover in Humans. Front Immunol 2017; 8:474. [PMID: 28487698 PMCID: PMC5403812 DOI: 10.3389/fimmu.2017.00474] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/05/2017] [Indexed: 01/18/2023] Open
Abstract
In vivo [6,6-2H2]-glucose labeling is a state-of-the-art technique for quantifying cell proliferation and cell disappearance in humans. However, there are discrepancies between estimates of T cell proliferation reported in short (1-day) versus long (7-day) 2H2-glucose studies and very-long (9-week) 2H2O studies. It has been suggested that these discrepancies arise from underestimation of true glucose exposure from intermittent blood sampling in the 1-day study. Label availability in glucose studies is normally approximated by a “square pulse” (Sq pulse). Since the body glucose pool is small and turns over rapidly, the availability of labeled glucose can be subject to large fluctuations and the Sq pulse approximation may be very inaccurate. Here, we model the pharmacokinetics of exogenous labeled glucose using a physiologically based pharmacokinetic (PBPK) model to assess the impact of a more complete description of label availability as a function of time on estimates of CD4+ and CD8+ T cell proliferation and disappearance. The model enabled us to predict the exposure to labeled glucose during the fasting and de-labeling phases, to capture the fluctuations of labeled glucose availability caused by the intake of food or high-glucose beverages, and to recalculate the proliferation and death rates of immune cells. The PBPK model was used to reanalyze experimental data from three previously published studies using different labeling protocols. Although using the PBPK enrichment profile decreased the 1-day proliferation estimates by about 4 and 7% for CD4 and CD8+ T cells, respectively, differences with the 7-day and 9-week studies remained significant. We conclude that the approximations underlying the “square pulse” approach—recently suggested as the most plausible hypothesis—only explain a component of the discrepancy in published T cell proliferation rate estimates.
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Affiliation(s)
- Julio Lahoz-Beneytez
- Computational Systems Biology, Bayer AG, Leverkusen, Germany.,Theoretical Immunology Group, Faculty of Medicine, Imperial College London, London, UK
| | | | - Derek Macallan
- Institute for Infection and Immunity, St. George's, University of London, London, UK.,St George's University Hospitals NHS Foundation Trust, London, UK
| | - Thomas Eissing
- Computational Systems Biology, Bayer AG, Leverkusen, Germany
| | | | - Becca Asquith
- Theoretical Immunology Group, Faculty of Medicine, Imperial College London, London, UK
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22
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Ötvös SB, Hsieh CT, Wu YC, Li JH, Chang FR, Fülöp F. Continuous-Flow Synthesis of Deuterium-Labeled Antidiabetic Chalcones: Studies towards the Selective Deuteration of the Alkynone Core. Molecules 2016; 21:318. [PMID: 26959006 PMCID: PMC6273355 DOI: 10.3390/molecules21030318] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 02/24/2016] [Indexed: 01/17/2023] Open
Abstract
Flow chemistry-based syntheses of deuterium-labeled analogs of important antidiabetic chalcones were achieved via highly controlled partial C≡C bond deuteration of the corresponding 1,3-diphenylalkynones. The benefits of a scalable continuous process in combination with on-demand electrolytic D2 gas generation were exploited to suppress undesired over-reactions and to maximize reaction rates simultaneously. The novel deuterium-containing chalcone derivatives may have interesting biological effects and improved metabolic properties as compared with the parent compounds.
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Affiliation(s)
- Sándor B Ötvös
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, Eötvös u. 6, H-6720 Szeged, Hungary.
| | - Chi-Ting Hsieh
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Yang-Chang Wu
- School of Pharmacy, College of Pharmacy, China Medical University, Taichung 40402, Taiwan.
- Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 40447, Taiwan.
| | - Jih-Heng Li
- Ph.D. Program in Toxicology and School of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Fang-Rong Chang
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
- Center for Infectious Disease and Cancer Research, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, Eötvös u. 6, H-6720 Szeged, Hungary.
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23
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Wang X, Schrader W. Selective Analysis of Sulfur-Containing Species in a Heavy Crude Oil by Deuterium Labeling Reactions and Ultrahigh Resolution Mass Spectrometry. Int J Mol Sci 2015; 16:30133-43. [PMID: 26694374 PMCID: PMC4691148 DOI: 10.3390/ijms161226205] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 12/04/2015] [Accepted: 12/09/2015] [Indexed: 02/06/2023] Open
Abstract
A heavy crude oil has been treated with deuterated alkylating reagents (CD₃I and C₂D₅I) and directly analyzed without any prior fractionation and chromatographic separation by high-field Orbitrap Fourier Transform Mass Spectrometry (FTMS) and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) using electrospray ionization (ESI). The reaction of a polycyclic aromatic sulfur heterocycles (PASHs) dibenzothiophene (DBT), in the presence of silver tetrafluoroborate (AgBF₄) with ethyl iodide (C₂H₅I) in anhydrous dichloroethane (DCE) was optimized as a sample reaction to study heavy crude oil mixtures, and the reaction yield was monitored and determined by proton nuclear magnetic resonance spectroscopy (¹H-NMR). The obtained conditions were then applied to a mixture of standard aromatic CH-, N-, O- and S-containing compounds and then a heavy crude oil, and only sulfur-containing compounds were selectively alkylated. The deuterium labeled alkylating reagents, iodomethane-d₃ (CD₃I) and iodoethane-d₅ (C₂D₅I), were employed to the alkylation of heavy crude oil to selectively differentiate the tagged sulfur species from the original crude oil.
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Affiliation(s)
- Xuxiao Wang
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.
| | - Wolfgang Schrader
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.
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24
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Karnawat V, Puranik M. Solution structures of purine base analogues 9-deazaguanine and 9-deazahypoxanthine. J Biomol Struct Dyn 2015; 34:640-52. [PMID: 25894214 DOI: 10.1080/07391102.2015.1042916] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Deaza analogues of nucleobases are potential drugs against infectious diseases caused by parasites. A caveat is that apart from binding their target parasite enzymes, they also bind and inhibit enzymes of the host. In order to design derivatives of deaza analogues which specifically bind target enzymes, knowledge of their molecular structure, protonation state, and predominant tautomers at physiological conditions is essential. We have employed resonance Raman spectroscopy at an excitation wavelength of 260 nm, to decipher solution structure of 9-deazaguanine (9DAG) and 9-deazahypoxanthine (9DAH). These are analogues of guanine and hypoxanthine, respectively, and have been exploited to study static complexes of nucleobase binding enzymes. Such enzymes are known to perturb pKa of their ligands, and thus, we also determined solution structures of these analogues at two, acidic and alkaline, pH. Structure of each possible protonation state and tautomer was computed using density functional theoretical calculations. Species at various pHs were identified based on isotopic shifts in experimental wavenumbers and by comparing these shifts with corresponding computed isotopic shifts. Our results show that at physiological pH, N1 of pyrimidine ring in 9DAG and 9DAH bears a proton. At lower pH, N3 is place of protonation, and at higher pH, deprotonation occurs at N1 position. The proton at N7 of purine ring remains intact even at pH 12.5. We have further compared these results with naturally occurring nucleotides. Our results identify key vibrational modes which can report on hydrogen bonding interactions, protonation and deprotonation in purine rings upon binding to the active site of enzymes.
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Affiliation(s)
- Vishakha Karnawat
- a Chemistry Department , Indian Institute of Science Education and Research , Pune 411008 , Maharashtra , India
| | - Mrinalini Puranik
- a Chemistry Department , Indian Institute of Science Education and Research , Pune 411008 , Maharashtra , India
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Cheng C, Vedananda S, Wu L, Harbeson S, Braman V, Tung R. Revealing the metabolic sites of atazanavir in human by parallel administrations of D-atazanavir analogs. J Mass Spectrom 2013; 48:1019-1031. [PMID: 24078243 DOI: 10.1002/jms.3247] [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: 04/12/2013] [Revised: 05/24/2013] [Accepted: 06/03/2013] [Indexed: 06/02/2023]
Abstract
Atazanavir (Reyataz(®)) is an important member of the HIV protease inhibitor class. Because of the complexity of its chemical structure, metabolite identification and structural elucidation face serious challenges. So far, only seven non-conjugated metabolites in human plasma have been reported, and their structural elucidation is not complete, especially for the major metabolites produced by oxidations. To probe the exact sites of metabolism and to elucidate the relationship among in vivo metabolites of atazanavir, we designed and performed two sets of experiments. The first set of experiments was to determine atazanavir metabolites in human plasma by LC-MS, from which more than a dozen metabolites were discovered, including seven new ones that have not been reported. The second set involved deuterium labeling on potential metabolic sites to generate D-atazanavir analogs. D-atazanavir analogs were dosed to human in parallel with atazanavir. Metabolites of D-atazanavir were identified by the same LC-MS method, and the results were compared with those of atazanavir. A metabolite structure can be readily elucidated by comparing the results of the analogs and the pathway by which the metabolite is formed can be proposed with confidence. Experimental results demonstrated that oxidation is the most common metabolic pathway of atazanavir, resulting in the formation of six metabolites of monooxidation (M1, M2, M7, M8, M13, and M14) and four of dioxidation (M15, M16, M17, and M18). The second metabolic pathway is hydrolysis, and the third is N-dealkylation. Metabolites produced by hydrolysis include M3, M4, and M19. Metabolites formed by N-dealkylation are M5, M6a, and M6b.
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Affiliation(s)
- Changfu Cheng
- Concert Pharmaceuticals, Inc., 99 Hayden Avenue, Suite 500, Lexington, MA, 02421, USA
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Tamogami S, Noge K, Abe M, Agrawal GK, Rakwal R. Methyl jasmonate is transported to distal leaves via vascular process metabolizing itself into JA-Ile and triggering VOCs emission as defensive metabolites. Plant Signal Behav 2012; 7:1378-81. [PMID: 22918499 PMCID: PMC3548852 DOI: 10.4161/psb.21762] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Plants have developed multifaceted defensive systems against adverse environmental factors. One such recognized system is the production of metabolites in plants. Jasmonic acid (JA) and its metabolite methyl jasmonate (MeJA) are known to play key roles in metabolites production. The role of MeJA as a mobile signal has been established in Arabidopsis and Solanaceae plants. However, it remains largely unclear how MeJA-based signaling is organized via its elicited metabolites. Here, we investigated the signaling ability of MeJA by means of vascular transport using Achyranthes bidentata as an experimental plant. Results showed that MeJA was transported and essentially metabolized into its active form JA-Ile in the distal undamaged leaves accompanied by emission of volatile organic compounds. Results presented and discussed therein provide convincing evidence that MeJA acts as a transportable inter-cellular mobile compound in plants self-defense scheme.
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Affiliation(s)
- Shigeru Tamogami
- Laboratory of Biologically Active Compounds; Department of Biological Production; Akita Prefectural University; Akita, Japan
- Correspondence to: Shigeru Tamogami, and Randeep Rakwal,
| | - Koji Noge
- Laboratory of Biologically Active Compounds; Department of Biological Production; Akita Prefectural University; Akita, Japan
| | - Makoto Abe
- Laboratory of Biologically Active Compounds; Department of Biological Production; Akita Prefectural University; Akita, Japan
| | - Ganesh Kumar Agrawal
- Research Laboratory for Biotechnology and Biochemistry (RLABB); Kathmandu, Nepal
| | - Randeep Rakwal
- Research Laboratory for Biotechnology and Biochemistry (RLABB); Kathmandu, Nepal
- Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Ibaraki, Japan
- Department of Anatomy I; School of Medicine; Showa University; Tokyo, Japan
- Correspondence to: Shigeru Tamogami, and Randeep Rakwal,
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Arora JS, Oe T, Blair IA. Synthesis of deuterium-labeled analogs of the lipid hydroperoxide-derived bifunctional electrophile 4-oxo-2( E)-nonenal. J Labelled Comp Radiopharm 2011; 54:247-251. [PMID: 25152561 DOI: 10.1002/jlcr.1860] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Lipid hydroperoxides undergo homolytic decomposition into the bifunctional 4-hydroxy-2(E)-nonenal and 4-oxo-2(E)-nonenal (ONE). These bifunctional electrophiles are highly reactive and can readily modify intracellular molecules including glutathione (GSH), deoxyribonucleic acid (DNA) and proteins. Lipid hydroperoxide-derived bifunctional electrophiles are thought to contribute to the pathogenesis of a number of diseases. ONE is an α,β-unsaturated aldehyde that can react in multiple ways and with glutathione, proteins and DNA. Heavy isotope-labeled analogs of ONE are not readily available for conducting mechanistic studies or for use as internal standards in mass spectrometry (MS)-based assays. An efficient onestep cost-effective method has been developed for the preparation of C-9 deuterium-labeled ONE. In addition, a method for specific deuterium labeling of ONE at C-2, C-3 or both C-2 and C-3 has been developed. This latter method involved the selective reduction of an intermediate alkyne either by lithium aluminum hydride or lithium aluminum deuteride and quenching with water or deuterium oxide. The availability of these heavy isotope analogs will be useful as internal standards for quantitative studies employing MS and for conducting mechanistic studies of complex interactions between ONE and DNA bases as well as between ONE and proximal amino acid residues in peptides and proteins.
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Affiliation(s)
- Jasbir S Arora
- Center for Cancer Pharmacology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Tomoyuki Oe
- Department of Bio-analytical Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aobaku, Sendai 980-8578, Japan
| | - Ian A Blair
- Center for Cancer Pharmacology, University of Pennsylvania, Philadelphia, PA 19104, USA
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Schenk DJ, Starks CM, Manna KR, Chappell J, Noel JP, Coates RM. Stereochemistry and deuterium isotope effects associated with the cyclization-rearrangements catalyzed by tobacco epiaristolochene and hyoscyamus premnaspirodiene synthases, and the chimeric CH4 hybrid cyclase. Arch Biochem Biophys 2006; 448:31-44. [PMID: 16309622 PMCID: PMC2883252 DOI: 10.1016/j.abb.2005.09.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2005] [Revised: 09/09/2005] [Accepted: 09/14/2005] [Indexed: 11/25/2022]
Abstract
Tobacco epiaristolochene and hyoscyamus premnaspirodiene synthases (TEAS and HPS) catalyze the cyclizations and rearrangements of (E,E)-farnesyl diphosphate (FPP) to the corresponding bicyclic sesquiterpene hydrocarbons. The complex mechanism proceeds through a tightly bound (R)-germacrene A intermediate and involves partitioning of a common eudesm-5-yl carbocation either by angular methyl migration, or by C-9 methylene rearrangement, to form the respective eremophilane and spirovetivane structures. In this work, the stereochemistry and timing of the proton addition and elimination steps in the mechanism were investigated by synthesis of substrates bearing deuterium labels in one or both terminal methyl groups, and in the pro-S and pro-R methylene hydrogens at C-8. Incubations of the labeled FPPs with recombinant TEAS and HPS, and with the chimeric CH4 hybrid cyclase having catalytic activities of both TEAS and HPS, and of unlabeled FPP in D2O, together with gas chromatography-mass spectrometry (GC-MS) and/or NMR analyses of the labeled products gave the following results: (1) stereospecific CH3-->CH2 eliminations at the cis-terminal methyl in all cases; (2) similar primary kinetic isotope effects (KIE) of 4.25-4.64 for the CH3-->CH2 eliminations; (3) a significant intermolecular KIE (1.33+/-0.03) in competitive cyclizations of unlabeled FPP and FPP-d6 to premnaspirodiene by HPS; (4) stereoselective incorporation of label from D2O into the 1beta position of epiaristolochene; (5) stereoselective eliminations of the 1beta and 9beta protons in formation of epiaristolochene and its delta(1(10)) isomer epieremophilene by TEAS and CH4; and (6) predominant loss of the 1alpha proton in forming the cyclohexene double bond of premnaspirodiene by HPS and CH4. The results are explained by consideration of the conformations of individual intermediates, and by imposing the requirement of stereoelectronically favorable proton additions and eliminations.
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Affiliation(s)
- David J. Schenk
- Department of Chemistry, University of Illinois, 600 South Mathews Ave., Urbana, IL 61801, USA
| | - Courtney M. Starks
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, Salk Institute for Biological Studies, 10010 North Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Kathleen Rising Manna
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546-0091, USA
| | - Joe Chappell
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546-0091, USA
| | - Joseph P. Noel
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, Salk Institute for Biological Studies, 10010 North Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Robert M. Coates
- Department of Chemistry, University of Illinois, 600 South Mathews Ave., Urbana, IL 61801, USA
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