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Zhong S, Liu R, Yue S, Wang P, Zhang Q, Ma C, Deng J, Qi Y, Zhu J, Liu CQ, Kawamura K, Fu P. Peatland Wildfires Enhance Nitrogen-Containing Organic Compounds in Marine Aerosols over the Western Pacific. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:10991-11002. [PMID: 38829627 DOI: 10.1021/acs.est.3c10125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
Peatland wildfires contribute significantly to the atmospheric release of light-absorbing organic carbon, often referred to as brown carbon. In this study, we examine the presence of nitrogen-containing organic compounds (NOCs) within marine aerosols across the Western Pacific Ocean, which are influenced by peatland fires from Southeast Asia. Employing ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in electrospray ionization (ESI) positive mode, we discovered that NOCs are predominantly composed of reduced nitrogenous bases, including CHN+ and CHON+ groups. Notably, the count of NOC formulas experiences a marked increase within plumes from peatland wildfires compared to those found in typical marine air masses. These NOCs, often identified as N-heterocyclic alkaloids, serve as potential light-absorbing chromophores. Furthermore, many NOCs demonstrate pyrolytic stability, engage in a variety of substitution reactions, and display enhanced hydrophilic properties, attributed to chemical processes such as methoxylation, hydroxylation, methylation, and hydrogenation that occur during emission and subsequent atmospheric aging. During the daytime atmospheric transport, aging of aromatic N-heterocyclic compounds, particularly in aliphatic amines prone to oxidation and reactions with amine, was observed. The findings underscore the critical role of peatland wildfires in augmenting nitrogen-containing organics in marine aerosols, underscoring the need for in-depth research into their effects on marine ecosystems and regional climatic conditions.
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Affiliation(s)
- Shujun Zhong
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
- Scientific Research Academy of Guangxi Environment Protection, Nanning, Guangxi Zhuang Autonomous Region 530022, China
| | - Rui Liu
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Siyao Yue
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Peng Wang
- Department of Atmospheric and Oceanic Sciences, Fudan University, Shanghai 200438, China
| | - Qiang Zhang
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Chao Ma
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Junjun Deng
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Yulin Qi
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Jialei Zhu
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Cong-Qiang Liu
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Kimitaka Kawamura
- Chubu Institute for Advanced Studies, Chubu University, Kasugai 487-8501, Japan
| | - Pingqing Fu
- Institute of Surface-Earth Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
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Łuczkowski M, Leszczyńska W, Wątły J, Clemens S, Krężel A. Phytochelatins Bind Zn(II) with Micro- to Picomolar Affinities without the Formation of Binuclear Complexes, Exhibiting Zinc Buffering and Muffling Rather than Storing Functions. Inorg Chem 2024; 63:10915-10931. [PMID: 38845098 PMCID: PMC11191002 DOI: 10.1021/acs.inorgchem.4c01707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 05/24/2024] [Accepted: 05/28/2024] [Indexed: 06/18/2024]
Abstract
Phytochelatins (PCs) are poly-Cys peptides containing a repeating γ-Glu-Cys motif synthesized in plants, algae, certain fungi, and worms by PC synthase from reduced glutathione. It has been shown that an excess of toxic metal ions induces their biosynthesis and that they are responsible for the detoxification process. Little is known about their participation in essential metal binding under nontoxic, basal conditions under which PC synthase is active. This study presents spectroscopic and thermodynamic interactions with the PC2-PC5 series, mainly focusing on the relations between Zn(II) complex stability and cellular Zn(II) availability. The investigations employed mass spectrometry, UV-vis spectroscopy, potentiometry, competition assays with zinc probes, and isothermal titration calorimetry (ITC). All peptides form ZnL complexes, while ZnL2 was found only for PC2, containing two to four sulfur donors in the coordination sphere. Binuclear species typical of Cd(II)-PC complexes are not formed in the case of Zn(II). Results demonstrate that the affinity for Zn(II) increases linearly from PC2 to PC4, ranging from micro- to low-picomolar. Further elongation does not significantly increase the stability. Stability elevation is driven mainly by entropic factors related to the chelate effect and conformational restriction rather than enthalpic factors related to the increasing number of sulfur donors. The affinity of the investigated PCs falls within the range of exchangeable Zn(II) concentrations (hundreds of pM) observed in plants, supporting for the first time a role of PCs both in buffering and in muffling cytosolic Zn(II) concentrations under normal conditions, not exposed to zinc excess, where short PCs have been identified in numerous studies. Furthermore, we found that Cd(II)-PC complexes demonstrate significantly higher metal capacities due to the formation of polynuclear species, which are lacking for Zn(II), supporting the role of PCs in Cd(II) storage (detoxification) and Zn(II) buffering and muffling. Our results on phytochelatins' coordination chemistry and thermodynamics are important for zinc biology and understanding the molecular basis of cadmium toxicity, leaving room for future studies.
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Affiliation(s)
- Marek Łuczkowski
- Department
of Chemical Biology, Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Weronika Leszczyńska
- Department
of Chemical Biology, Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Joanna Wątły
- Department
of Chemical Biology, Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Stephan Clemens
- Department
of Plant Physiology, Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, 95440 Bayreuth, Germany
| | - Artur Krężel
- Department
of Chemical Biology, Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
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3
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Cu and Zn Interactions with Peptides Revealed by High-Resolution Mass Spectrometry. Pharmaceuticals (Basel) 2022; 15:ph15091096. [PMID: 36145317 PMCID: PMC9504920 DOI: 10.3390/ph15091096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 11/26/2022] Open
Abstract
Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by abnormal extracellular amyloid-beta (Aβ) peptide depositions in the brain. Among amorphous aggregates, altered metal homeostasis is considered a common risk factor for neurodegeneration known to accelerate plaque formation. Recently, peptide-based drugs capable of inhibiting amyloid aggregation have achieved unprecedented scientific and pharmaceutical interest. In response to metal ions binding to Aβ peptide, metal chelation was also proposed as a therapy in AD. The present study analyzes the interactions formed between NAP octapeptide, derived from activity-dependent neuroprotective protein (ADNP), amyloid Aβ(9–16) fragment and divalent metal ions such as Cu and Zn. The binding affinity studies for Cu and Zn ions of synthetic NAP peptide and Aβ(9–16) fragment were investigated by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), electrospray ion trap mass spectrometry (ESI-MS) and atomic force microscopy (AFM). Both mass spectrometric methods confirmed the formation of metal–peptide complexes while the AFM technique provided morphological and topographic information regarding the influence of metal ions upon peptide crystallization. Our findings showed that due to a rich histidine center, the Aβ(9–16) fragment is capable of binding metal ions, thus becoming stiff and promoting aggregation of the entire amyloid peptide. Apart from this, the protective effect of the NAP peptide was found to rely on the ability of this octapeptide to generate both chelating properties with metals and interactions with Aβ peptide, thus stopping its folding process.
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4
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Gaigher B, do Nascimento da Silva E, Lacerda Sanches V, Fernanda Milani R, Galland F, Cadore S, Grancieri M, Bertoldo Pacheco MT. Formulations with microencapsulated Fe–peptides improve in vitro bioaccessibility and bioavailability. Curr Res Food Sci 2022; 5:687-697. [PMID: 35465643 PMCID: PMC9019146 DOI: 10.1016/j.crfs.2022.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 03/04/2022] [Accepted: 03/17/2022] [Indexed: 11/25/2022] Open
Abstract
The bioaccessibility and the bioavailability of iron complexed to peptides (active) in microparticles forms contained in dry beverages formulations were evaluated. The peptide-iron complexes microparticles were obtained by spray drying and added in three dry formulations (tangerine, strawberry, and chocolate flavors). The peptides isolated by iron ion affinity (IMAC-Fe III) had their biological activity predicted by BIOPEP® database and were evaluated by molecular coupling. The bioaccessibility was evaluated by solubility and dialysability and the bioavalability was assessed by Caco-2 cellular model. The proportion 10:1 of peptide-iron complexes presented higher rates of bioaccessibility (49%) and bioavailability (56%). The microparticle with peptide-iron complex showed greater solubility after digestion (39.1%), bioaccessibility (19.8%), and bioavailability (34.8%) than the ferrous sulfate salt (control) for the three assays (10.2%; 12.9%; 9.7%, respectively). Tangerine and strawberry formulations contributed to the iron absorption according to the results of bioaccessibility (36.2%, 30.0% respectively) and bioavailability (80.5%, 84.1%, respectively). The results showed that iron peptide complexation and microencapsulation process improve the bioaccessibility and bioavailability when incorporated into formulations. Iron solubility is increased in iron peptide complexes. In silico interaction between peptides > 5 KDa and ferric iron (Fe2+). Microparticle with Fe-peptides increase iron bioavailability after digestion. Microparticle formulations improve iron bioaccessibility and bioavailability.
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Płonka D, Kotuniak R, Dąbrowska K, Bal W. Electrospray-Induced Mass Spectrometry Is Not Suitable for Determination of Peptidic Cu(II) Complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:2766-2776. [PMID: 34738801 PMCID: PMC8640992 DOI: 10.1021/jasms.1c00206] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 06/13/2023]
Abstract
The toolset of mass spectrometry (MS) is still expanding, and the number of metal ion complexes researched this way is growing. The Cu(II) ion forms particularly strong peptide complexes of biological interest which are frequent objects of MS studies, but quantitative aspects of some reported results are at odds with those of experiments performed in solution. Cu(II) complexes are usually characterized by fast ligand exchange rates, despite their high affinity, and we speculated that such kinetic lability could be responsible for the observed discrepancies. In order to resolve this issue, we selected peptides belonging to the ATCUN family characterized with high and thoroughly determined Cu(II) binding constants and re-estimated them using two ESI-MS techniques: standard conditions in combination with serial dilution experiments and very mild conditions for competition experiments. The sample acidification, which accompanies the electrospray formation, was simulated with the pH-jump stopped-flow technique. Our results indicate that ESI-MS should not be used for quantitative studies of Cu(II)-peptide complexes because the electrospray formation process compromises the entropic contribution to the complex stability, yielding underestimations of complex stability constants.
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Byrne L, Hynes MJ, Connolly CD, Murphy RA. Influence of the Chelation Process on the Stability of Organic Trace Mineral Supplements Used in Animal Nutrition. Animals (Basel) 2021; 11:1730. [PMID: 34200569 PMCID: PMC8227544 DOI: 10.3390/ani11061730] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/02/2021] [Accepted: 06/08/2021] [Indexed: 12/26/2022] Open
Abstract
The effect of the chelation process on the pH-dependent stability of organic trace minerals (OTMs) used as mineral supplements in animal nutrition was assessed using analytical techniques such as potentiometry, Fourier Transform Infrared Spectroscopy (FTIRS) and amino acid profiling. The aim was to understand the influence and relative importance of the manufacturing conditions on mineral chelation and the subsequent pH stability of OTMs. A selection of OTMs were assessed over a wide pH range to account for the typical environmental changes encountered in the gastrointestinal (GI) tract. In the case of proteinate type products, the potentiometric assessment of free mineral concentration indicated that the hydrolysis procedure used to generate the chelating peptides was the major influencer of the pH stability of the products. Many products are available under the umbrella term "OTMs", including amino acid complexes, amino acid chelates, polysaccharide complexes and proteinates. Significant differences in the pH-dependent stability of a range of commercially available OTMs were observed.
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Affiliation(s)
- Laurann Byrne
- Alltech Bioscience Centre, Summerhill Road, Dunboyne, A86 X006 Co. Meath, Ireland; (C.D.C.); (R.A.M.)
| | - Michael J. Hynes
- School of Chemistry, National University of Ireland, H91 TK33 Galway, Ireland;
| | - Cathal D. Connolly
- Alltech Bioscience Centre, Summerhill Road, Dunboyne, A86 X006 Co. Meath, Ireland; (C.D.C.); (R.A.M.)
| | - Richard A. Murphy
- Alltech Bioscience Centre, Summerhill Road, Dunboyne, A86 X006 Co. Meath, Ireland; (C.D.C.); (R.A.M.)
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7
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Wątły J, Łuczkowski M, Padjasek M, Krężel A. Phytochelatins as a Dynamic System for Cd(II) Buffering from the Micro- to Femtomolar Range. Inorg Chem 2021; 60:4657-4675. [PMID: 33736430 PMCID: PMC8041291 DOI: 10.1021/acs.inorgchem.0c03639] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Indexed: 01/30/2023]
Abstract
Phytochelatins (PCs) are short Cys-rich peptides with repeating γ-Glu-Cys motifs found in plants, algae, certain fungi, and worms. Their biosynthesis has been found to be induced by heavy metals-both biogenic and toxic. Among all metal inducers, Cd(II) has been the most explored from a biological and chemical point of view. Although Cd(II)-induced PC biosynthesis has been widely examined, still little is known about the structure of Cd(II) complexes and their thermodynamic stability. Here, we systematically investigated glutathione (GSH) and PC2-PC6 systems, with regard to their complex stoichiometries and spectroscopic and thermodynamic properties. We paid special attention to the determination of stability constants using several complementary techniques. All peptides form CdL complexes, but CdL2 was found for GSH, PC2, and partially for PC3. Moreover, binuclear species CdxLy were identified for the series PC3-PC6 in an excess of Cd(II). Potentiometric and competition spectroscopic studies showed that the affinity of Cd(II) complexes increases from GSH to PC4 almost linearly from micromolar (log K7.4GSH = 5.93) to the femtomolar range (log K7.4PC4 = 13.39) and additional chain elongation does not increase the stability significantly. Data show that PCs form an efficient system which buffers free Cd(II) ions in the pico- to femtomolar range under cellular conditions, avoiding significant interference with Zn(II) complexes. Our study confirms that the favorable entropy change is the factor governing the elevation of phytochelatins' stability and illuminates the importance of the chelate effect in shifting the free Gibbs energy.
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Affiliation(s)
| | | | - Michał Padjasek
- Department of Chemical Biology, Faculty
of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Artur Krężel
- Department of Chemical Biology, Faculty
of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
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8
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Glasmacher S, Gertsch J. Characterization of pepcan-23 as pro-peptide of RVD-hemopressin (pepcan-12) and stability of hemopressins in mice. Adv Biol Regul 2021; 80:100808. [PMID: 33799079 DOI: 10.1016/j.jbior.2021.100808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/02/2021] [Accepted: 03/18/2021] [Indexed: 11/26/2022]
Abstract
Hemopressins ((x)-PVNFKLLSH) or peptide endocannabinoids (pepcans) can bind to cannabinoid receptors. RVD-hemopressin (pepcan-12) was shown to act as endogenous allosteric modulator of cannabinoid receptors, with opposite effects on CB1 and CB2, respectively. Moreover, the N-terminally elongated pepcan-23 was detected in different tissues and was postulated to be the pro-peptide of RVD-hemopressin. Currently, data about the pharmacokinetics, tissue distribution and stability of hemopressin-type peptides are lacking. Here we investigated the secondary structure and physiological role of pepcan-23 as precursor of RVD-hemopressin. We assessed the metabolic stability of these peptides, including hemopressin. Using LC-ESI-MS/MS, pepcan-23 was measured in mouse tissues and human whole blood (~50 pmol/mL) and in plasma was the most stable endogenous peptide containing the hemopressin sequence. Using peptide spiked human whole blood, mouse adrenal gland and liver homogenates demonstrate that pepcan-23 acts as endogenous pro-peptide of RVD-hemopressin. Furthermore, administered pepcan-23 converted to RVD-hemopressin in mice. In circular dichroism spectroscopy, pepcan-23 showed a helix-unordered-helix structure and efficiently formed complexes with divalent metal ions, in particular Cu(II) and Ni(II). Hemopressin and RVD-hemopressin were not bioavailable to the brain and showed poor stability in plasma, in agreement with their overall poor biodistribution. Acute hemopressin administration (100 mg/kg) did not modulate endogenous RVD-hemopressin/pepcan-23 levels or influence the endocannabinoid lipidome but increased 1-stearoyl-2-arachidonoyl-sn-glycerol. Overall, we show that pepcan-23 is a biological pro-peptide of RVD-hemopressin and divalent metal ions may regulate this process. Given the lack of metabolic stability of hemopressins, administration of pepcan-23 as pro-peptide may be suitable in pharmacological experiments as it is converted to RVD-hemopressin in vivo.
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Affiliation(s)
- Sandra Glasmacher
- Institute of Biochemistry and Molecular Medicine, University of Bern, CH-3012, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland
| | - Jürg Gertsch
- Institute of Biochemistry and Molecular Medicine, University of Bern, CH-3012, Bern, Switzerland.
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9
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Liu XR, Zhang MM, Gross ML. Mass Spectrometry-Based Protein Footprinting for Higher-Order Structure Analysis: Fundamentals and Applications. Chem Rev 2020; 120:4355-4454. [PMID: 32319757 PMCID: PMC7531764 DOI: 10.1021/acs.chemrev.9b00815] [Citation(s) in RCA: 130] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Proteins adopt different higher-order structures (HOS) to enable their unique biological functions. Understanding the complexities of protein higher-order structures and dynamics requires integrated approaches, where mass spectrometry (MS) is now positioned to play a key role. One of those approaches is protein footprinting. Although the initial demonstration of footprinting was for the HOS determination of protein/nucleic acid binding, the concept was later adapted to MS-based protein HOS analysis, through which different covalent labeling approaches "mark" the solvent accessible surface area (SASA) of proteins to reflect protein HOS. Hydrogen-deuterium exchange (HDX), where deuterium in D2O replaces hydrogen of the backbone amides, is the most common example of footprinting. Its advantage is that the footprint reflects SASA and hydrogen bonding, whereas one drawback is the labeling is reversible. Another example of footprinting is slow irreversible labeling of functional groups on amino acid side chains by targeted reagents with high specificity, probing structural changes at selected sites. A third footprinting approach is by reactions with fast, irreversible labeling species that are highly reactive and footprint broadly several amino acid residue side chains on the time scale of submilliseconds. All of these covalent labeling approaches combine to constitute a problem-solving toolbox that enables mass spectrometry as a valuable tool for HOS elucidation. As there has been a growing need for MS-based protein footprinting in both academia and industry owing to its high throughput capability, prompt availability, and high spatial resolution, we present a summary of the history, descriptions, principles, mechanisms, and applications of these covalent labeling approaches. Moreover, their applications are highlighted according to the biological questions they can answer. This review is intended as a tutorial for MS-based protein HOS elucidation and as a reference for investigators seeking a MS-based tool to address structural questions in protein science.
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Affiliation(s)
| | | | - Michael L. Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA, 63130
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10
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Caetano-Silva ME, Netto FM, Bertoldo-Pacheco MT, Alegría A, Cilla A. Peptide-metal complexes: obtention and role in increasing bioavailability and decreasing the pro-oxidant effect of minerals. Crit Rev Food Sci Nutr 2020; 61:1470-1489. [PMID: 32370550 DOI: 10.1080/10408398.2020.1761770] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Bioactive peptides derived from food protein sources have been widely studied in the last years, and scientific researchers have been proving their role in human health, beyond their nutritional value. Several bioactivities have been attributed to these peptides, such as immunomodulatory, antimicrobial, antioxidant, antihypertensive, and opioid. Among them, metal-binding capacity has gained prominence. Mineral chelating peptides have shown potential to be applied in food products so as to decrease mineral deficiencies since peptide-metal complexes could enhance their bioavailability. Furthermore, many studies have been investigating their potential to decrease the Fe pro-oxidant effect by forming a stable structure with the metal and avoiding its interaction with other food constituents. These complexes can be formed during gastrointestinal digestion or can be synthesized prior to intake, with the aim to protect the mineral through the gastrointestinal tract. This review addresses: (i) the amino acid residues for metal-binding peptides and their main protein sources, (ii) peptide-metal complexation prior to or during gastrointestinal digestion, (iii) the function of metal (especially Fe, Ca, and Zn)-binding peptides on the metal bioavailability and (iv) their reactivity and possible pro-oxidant and side effects.
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Affiliation(s)
| | - Flavia Maria Netto
- Faculty of Food Engineering, University of Campinas (UNICAMP), Campinas, SP, Brazil
| | | | - Amparo Alegría
- Nutrition and Food Science Area, Faculty of Pharmacy, University of Valencia, Valencia, Spain
| | - Antonio Cilla
- Nutrition and Food Science Area, Faculty of Pharmacy, University of Valencia, Valencia, Spain
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11
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Chen G, Fan M, Liu Y, Sun B, Liu M, Wu J, Li N, Guo M. Advances in MS Based Strategies for Probing Ligand-Target Interactions: Focus on Soft Ionization Mass Spectrometric Techniques. Front Chem 2019; 7:703. [PMID: 31709232 PMCID: PMC6819514 DOI: 10.3389/fchem.2019.00703] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/08/2019] [Indexed: 12/12/2022] Open
Abstract
The non-covalent interactions between small drug molecules and disease-related proteins (ligand-target interactions) mediate various pharmacological processes in the treatment of different diseases. The development of the analytical methods to assess those interactions, including binding sites, binding energies, stoichiometry and association-dissociation constants, could assist in clarifying the mechanisms of action, precise treatment of targeted diseases as well as the targeted drug discovery. For the last decades, mass spectrometry (MS) has been recognized as a powerful tool to study the non-covalent interactions of the ligand-target complexes with the characteristics of high sensitivity, high-resolution, and high-throughput. Soft ionization mass spectrometry, especially the electrospray mass spectrometry (ESI-MS) and matrix assisted laser desorption ionization mass spectrometry (MALDI-MS), could achieve the complete transformation of the target analytes into the gas phase, and subsequent detection of the small drug molecules and disease-related protein complexes, and has exerted great advantages for studying the drug ligands-protein targets interactions, even in case of identifying active components as drug ligands from crude extracts of medicinal plants. Despite of other analytical techniques for this purpose, such as the NMR and X-ray crystallography, this review highlights the principles, research hotspots and recent applications of the soft ionization mass spectrometry and its hyphenated techniques, including hydrogen-deuterium exchange mass spectrometry (HDX-MS), chemical cross-linking mass spectrometry (CX-MS), and ion mobility spectrometry mass spectrometry (IMS-MS), in the study of the non-covalent interactions between small drug molecules and disease-related proteins.
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Affiliation(s)
- Guilin Chen
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, China
| | - Minxia Fan
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, China
- Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Ye Liu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, China
| | - Baoqing Sun
- State Key Laboratory of Respiratory Disease, National Clinical Center for Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, First Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Meixian Liu
- State Key Laboratory for Quality Research of Chinese Medicines, Macau University of Science and Technology, Taipa, Macau
| | - Jianlin Wu
- State Key Laboratory for Quality Research of Chinese Medicines, Macau University of Science and Technology, Taipa, Macau
| | - Na Li
- State Key Laboratory for Quality Research of Chinese Medicines, Macau University of Science and Technology, Taipa, Macau
| | - Mingquan Guo
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, China
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12
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Pangavhane S, Makrlík E, Ruzza P, Kašička V. Affinity capillary electrophoresis employed for determination of stability constants of antamanide complexes with univalent and divalent cations in methanol. Electrophoresis 2019; 40:2321-2328. [DOI: 10.1002/elps.201900043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/18/2019] [Accepted: 04/29/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Sachin Pangavhane
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences Prague Czechia
- University of Chemistry and Technology Prague Czechia
| | - Emanuel Makrlík
- Faculty of Environmental SciencesCzech University of Life Sciences Prague Czechia
| | - Paolo Ruzza
- Institute of Biomolecular Chemistry of CNR, Padua Unit Padua Italy
| | - Václav Kašička
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences Prague Czechia
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13
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Iacobucci C, Schäfer M, Sinz A. Free radical-initiated peptide sequencing (FRIPS)-based cross-linkers for improved peptide and protein structure analysis. MASS SPECTROMETRY REVIEWS 2019; 38:187-201. [PMID: 29660147 DOI: 10.1002/mas.21568] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 03/09/2018] [Indexed: 06/08/2023]
Abstract
Free radical-initiated peptide sequencing (FRIPS) has recently been introduced as an analytical strategy to create peptide radical ions in a predictable and effective way by collisional activation of specifically modified peptides ions. FRIPS is based on the unimolecular dissociation of open-shell ions and yields fragments that resemble those obtained by electron capture dissociation (ECD) or electron transfer dissociation (ETD). In this review article, we describe the fundamentals of FRIPS and highlight its fruitful combination with chemical cross-linking/mass spectrometry (MS) as a highly promising option to derive complementary structural information of peptides and proteins. FRIPS does not only yield exhaustive sequence information of cross-linked peptides, but also defines the exact cross-linking sites of the connected peptides. The development of more advanced FRIPS cross-linkers that extend the FRIPS-based cross-linking/MS approach to the study of large protein assemblies and protein interaction networks can be eagerly anticipated.
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Affiliation(s)
- Claudio Iacobucci
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale), D-06120, Germany
| | - Mathias Schäfer
- Department of Chemistry, Institute of Organic Chemistry, University of Cologne, Cologne, D-50939, Germany
| | - Andrea Sinz
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale), D-06120, Germany
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Stoichiometry of Heavy Metal Binding to Peptides Involved in Alzheimer’s Disease: Mass Spectrometric Evidence. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1140:401-415. [DOI: 10.1007/978-3-030-15950-4_23] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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15
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Caetano-Silva ME, Cilla A, Bertoldo-Pacheco MT, Netto FM, Alegría A. Evaluation of in vitro iron bioavailability in free form and as whey peptide-iron complexes. J Food Compost Anal 2018. [DOI: 10.1016/j.jfca.2017.03.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Kostyukevich YI, Kononikhin AS, Indeykina MI, Popov IA, Bocharov KV, Spassky AI, Kozin SA, Makarov AA, Nikolaev EN. Secondary structure of Aβ(1–16) complexes with zinc: A study in the gas phase using deuterium/hydrogen exchange and ultra-high-resolution mass spectrometry. Mol Biol 2017. [DOI: 10.1134/s0026893317030104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Kostyukevich Y, Yacovlev P, Kononikhin A, Popov I, Bugrova A, Starodubtzeva N, Nikolaev E. The use of H/D exchange for secondary structure characterization of supermetallized complexes of ubiquitin with cerium(III). RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2016. [DOI: 10.1134/s1068162016040117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Kostyukevich YI, Kononikhin AS, Popov IA, Indeykina MI, Nikolaev EN. Supermetallization of Substance P during electrospray ionization. MENDELEEV COMMUNICATIONS 2016. [DOI: 10.1016/j.mencom.2016.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Enhancement of ionization efficiency of mass spectrometric analysis from non-electrospray ionization friendly solvents with conventional and novel ionization techniques. Anal Chim Acta 2015; 897:45-52. [DOI: 10.1016/j.aca.2015.09.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 09/17/2015] [Accepted: 09/19/2015] [Indexed: 11/21/2022]
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20
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Kostyukevich Y, Kononikhin A, Popov I, Indeykina M, Kozin SA, Makarov AA, Nikolaev E. Supermetallization of peptides and proteins during electrospray ionization. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:1079-1087. [PMID: 28338253 DOI: 10.1002/jms.3622] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 04/26/2015] [Accepted: 05/26/2015] [Indexed: 06/06/2023]
Abstract
The formation of metal-peptide complexes during electrospray ionization (ESI) is a widely known phenomenon and is often considered to be undesirable. Such effect considerably limits the use of ESI mass spectrometry for the investigation of biologically relevant metal-peptide compounds that are present in the solution and play critical roles in many bioprocesses such as progression of neurodegenerative diseases. In the article, it is demonstrated that under specific conditions such as high temperature of the desolvating capillary, an interesting effect, which can be called as 'supermetallization', occurs. Using a model peptide Αβ amyloid domain 1-16, it was observed that an increase in the temperature of the desolvating capillary results in multiple substitutions of hydrogen atoms by Zn atoms in this peptide. At high temperatures (T ~ 400 °C), up to 11 zinc atoms can be covalently bound to (1-16) Αβ. It was observed that supermetallization of (1-16) Αβ depends on the solvent composition and pH. Supermetallization was also demonstrated for proteins, such as ubiquitin and cytochrome C. That proves that the supermetallization is a general phenomenon for peptides and proteins. For the structural investigation of supermetallized complexes, electron-capture dissociation (ECD) fragmentation was applied. The effect of hydrogen rearranging during ECD was observed. In addition, quantum chemical calculations were used to estimate the possible structures of different supermetallized complexes. These results allow a more deep understanding of the limitations of the use of ESI mass spectrometry for the investigation of biologically relevant metal-peptide complexes. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Yury Kostyukevich
- Skolkovo Institute of Science and Technology, Novaya St., 100, Skolkovo, 143025, Russia
- Institute for Energy Problems of Chemical Physics, Russian Academy of Sciences, Leninskij pr. 38 k.2, 119334, Moscow, Russia
- Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow, Russia
| | - Alexey Kononikhin
- Institute for Energy Problems of Chemical Physics, Russian Academy of Sciences, Leninskij pr. 38 k.2, 119334, Moscow, Russia
- Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow, Russia
| | - Igor Popov
- Emanuel Institute for Biochemical Physics, Russian Academy of Sciences, Kosygina st. 4, 119334, Moscow, Russia
- Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Maria Indeykina
- Institute for Energy Problems of Chemical Physics, Russian Academy of Sciences, Leninskij pr. 38 k.2, 119334, Moscow, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Sergey A Kozin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Alexander A Makarov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Eugene Nikolaev
- Skolkovo Institute of Science and Technology, Novaya St., 100, Skolkovo, 143025, Russia
- Institute for Energy Problems of Chemical Physics, Russian Academy of Sciences, Leninskij pr. 38 k.2, 119334, Moscow, Russia
- Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow, Russia
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dos Santos PR, Ely MR, Dumas F, Moura S. Synthesis, structural characterization and previous cytotoxicity assay of Zn(II) complex containing 1,10-phenanthroline and 2,2′-bipyridine with valproic acid. Polyhedron 2015. [DOI: 10.1016/j.poly.2015.02.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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22
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Andries C, Manea M, Drochioiu G, Gradinaru R. New insights into coenzyme A interaction with mercury ions provided by mass spectrometric and circular dichroism spectroscopic approaches. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2015; 21:97-102. [PMID: 26181283 DOI: 10.1255/ejms.1361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The interaction of coenzyme A (CoA) with mercury ions was investigated using electrospray ionization mass spectrometry and circular dichroism spectroscopy. Our results indicated a 1:1 stoichiometric CoA-Hg complex at physiological pH. Furthermore, the CoA conformation considerably changed in the presence of mercury ions. In addition, a by-product of the reaction, thiocoenzyme A, was identified using mass spectrometry.
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Affiliation(s)
- Claudia Andries
- Alexandru Ioan Cuza University of Iasi, Department of Chemistry, 11 Carol I, Iasi-700506, Romania..
| | - Marilena Manea
- University of Konstanz, Department of Chemistry and Zukunftskolleg, 78457 Konstanz, Germany.. marilena.manea@uni- konstanz.de
| | - Gabi Drochioiu
- Alexandru Ioan Cuza University of Iasi, Department of Chemistry, 11 Carol I, Iasi-700506, Romania..
| | - Robert Gradinaru
- Alexandru Ioan Cuza University of Iasi, Department of Chemistry, 11 Carol I, Iasi-700506, Romania..
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Mustapha AM, Pasilis SP. Probing uranyl(VI) speciation in the presence of amidoxime ligands using electrospray ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:2135-2142. [PMID: 23996386 DOI: 10.1002/rcm.6672] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 06/29/2013] [Accepted: 06/30/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Extraction processes using poly(acrylamidoxime) resins are being developed to extract uranium from seawater. The main complexing agents in these resins are thought to be 2,6-dihydroxyiminopiperidine (DHIP) and N(1),N(5)-dihydroxypentanediimidamide (DHPD), which form strong complexes with uranyl(VI) at the pH of seawater. It is important to understand uranyl(VI) speciation in the presence of these and similar amidoxime ligands to understand factors affecting uranyl(VI) adsorption to the poly(acrylamidoxime) resins. METHODS Experiments were carried out in positive ion mode on a quadrupole ion trap mass spectrometer equipped with an electrospray ionization source. The ligands investigated were DHIP, DHPD, and N(1),N(2)-dihydroxyethanediimidamide (DHED). DHED and DHPD differ only in the number of carbons separating the oxime groups. The effects on the mass spectra of changes in uranyl(VI):ligand ratio, pH, and ligand type were examined. RESULTS DHIP binds uranyl(VI) more effectively than DHPD or DHED in the pH range investigated, forming ions derived from solution-phase species with uranyl(VI):DHIP stoichiometries of 1:1, 1:2, and 2:3. The 2:3 uranyl(VI):DHIP complex appears to be a previously undescribed solution species. Ions related to uranyl(VI):DHPD complexes were detected in very low abundance. DHED is a more effective complexing agent for uranyl(VI) than DHPD, forming ions having uranyl(VI):DHED stoichiometries of 1:1, 1:2, 1:3, and 2:3. CONCLUSIONS This study presents a first look at the solution chemistry of uranyl(VI)-amidoxime complexes using electrospray ionization mass spectrometry. The appearance of previously undescribed solution species suggests that the uranyl-amidoxime system is a rich and relatively complex one, requiring a more in-depth investigation.
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Affiliation(s)
- Adetayo M Mustapha
- Department of Chemistry, University of Idaho, Moscow, ID 83844-2343, USA
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24
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Gillet FX, Cattoni DI, Petiot-Bécard S, Delalande F, Poignavent V, Brizard JP, Bessin Y, Dorsselaer AV, Declerck N, Sanglier-Cianférani S, Brugidou C, Vignols F. The RYMV-Encoded Viral Suppressor of RNA Silencing P1 Is a Zinc-Binding Protein with Redox-Dependent Flexibility. J Mol Biol 2013; 425:2423-35. [DOI: 10.1016/j.jmb.2013.03.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/14/2013] [Accepted: 03/18/2013] [Indexed: 10/27/2022]
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25
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Moghaddam MB, Fridgen TD. IRMPD Spectroscopic Study of Microsolvated [Na(GlyAla)]+ and [Ca(GlyAla–H)]+ and the Blue Shifting of the Hydrogen-Bonded Amide Stretch with Each Water Addition. J Phys Chem B 2013; 117:6157-64. [DOI: 10.1021/jp402217g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Maryam B. Moghaddam
- Department
of Chemistry, Memorial University, St. John’s, Newfoundland
and Labrador, Canada A1B 3X7 Canada
| | - Travis D. Fridgen
- Department
of Chemistry, Memorial University, St. John’s, Newfoundland
and Labrador, Canada A1B 3X7 Canada
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Li H, Xie H, Yang N, Huang Y, Sun L, Li G. Design of a bi-functional peptide for protein assays: observation of cortactin expression in human placenta. Chem Commun (Camb) 2013; 49:5387-9. [DOI: 10.1039/c3cc42353k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Zidane F, Matéos A, Cakir-Kiefer C, Miclo L, Rahuel-Clermont S, Girardet JM, Corbier C. Binding of divalent metal ions to 1–25 β-caseinophosphopeptide: An isothermal titration calorimetry study. Food Chem 2012; 132:391-8. [DOI: 10.1016/j.foodchem.2011.11.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/20/2011] [Accepted: 11/01/2011] [Indexed: 11/15/2022]
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28
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Hu L, Paul Fawcett J, Gu J. Protein target discovery of drug and its reactive intermediate metabolite by using proteomic strategy. Acta Pharm Sin B 2012. [DOI: 10.1016/j.apsb.2012.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Lu Y, Prudent M, Fauvet B, Lashuel HA, Girault HH. Phosphorylation of α-Synuclein at Y125 and S129 alters its metal binding properties: implications for understanding the role of α-Synuclein in the pathogenesis of Parkinson's Disease and related disorders. ACS Chem Neurosci 2011; 2:667-75. [PMID: 22860160 DOI: 10.1021/cn200074d] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 09/13/2011] [Indexed: 12/15/2022] Open
Abstract
α-Synuclein (α-syn) is a 140-amino acid protein that plays a central role in the pathogenesis of Parkinson's disease (PD) and other synucleinopathies. However, the molecular determinants that are responsible for triggering and/or propagating α-syn aggregation and toxicity remain poorly understood. Several studies have suggested that there are direct interactions between different metals and α-syn, but the role of metal ions and α-syn in the pathogenesis of PD is not firmly established. Interestingly, the majority of disease-associated post-translational modifications (PTMs) (e.g., truncation, phosphorylation, and nitration) of α-syn occur at residues within the C-terminal region (Y125, S129, Y133, and Y136) and in very close proximity to the putative metal binding sites. Therefore, we hypothesized that phosphorylation within this domain could influence the α-syn-metal interactions. In this paper, we sought to map the interactions between the di- and trivalent cations, Cu(II), Pb(II), Fe(II), and Fe(III), and the C-terminal region of α-syn encompassing residues 107-140 and to determine how phosphorylation at S129 or Y125 alters the specificity and binding affinity of metals using electrospray ionization-mass spectrometry (ESI-MS) and fluorescence spectroscopy. We demonstrate that D115-M116 and P128-S129 act as additional Cu(II) binding sites and show for the first time that the residues P128-S129 and D119 are also involved in Pb(II) and Fe(II) coordination, although D119 is not essential for binding to Fe(II) and Pb(II). Furthermore, we demonstrate that phosphorylation at either Y125 or S129 increases the binding affinity of Cu(II), Pb(II), and Fe(II), but not Fe(III). Additionally, we also show that phosphorylations at these residues lead to a shift in the binding sites of metal ions from the N-terminus to the C-teminus. Together, our findings provide critical insight into and expand our understanding of the molecular and structural bases underlying the interactions between α-syn and metal ions, including the identification of novel metal binding sites, and highlight the potential importance of cross-talk between post-translational modifications and metal ion binding in modulating α-syn functional and aggregation properties that are regulated by its C-terminal domain.
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Affiliation(s)
- Yu Lu
- Laboratoire d’Electrochimie Physique et Analytique, Station 6, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Michel Prudent
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, Station 15, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Bruno Fauvet
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, Station 15, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Hilal A. Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, Station 15, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Hubert H. Girault
- Laboratoire d’Electrochimie Physique et Analytique, Station 6, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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