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Koy C, Röwer C, Thiesen HJ, Neamtu A, Glocker MO. Intact Transition Epitope Mapping-Force Interferences by Variable Extensions (ITEM-FIVE). Biomolecules 2024; 14:454. [PMID: 38672470 PMCID: PMC11048379 DOI: 10.3390/biom14040454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
Investigations on binding strength differences of non-covalent protein complex components were performed by mass spectrometry. T4 fibritin foldon (T4Ff) is a well-studied miniprotein, which together with its biotinylated version served as model system to represent a compactly folded protein to which an Intrinsically Disordered Region (IDR) was attached. The apparent enthalpies of the gas phase dissociation reactions of the homo-trimeric foldon F-F-F and of the homo-trimeric triply biotinylated foldon bF-bF-bF have been determined to be rather similar (3.32 kJ/mol and 3.85 kJ/mol) but quite distinct from those of the singly and doubly biotinylated hetero-trimers F-F-bF and F-bF-bF (1.86 kJ/mol and 1.08 kJ/mol). Molecular dynamics simulations suggest that the ground states of the (biotinylated) T4Ff trimers are highly symmetric and well comparable to each other, indicating that the energy levels of all four (biotinylated) T4Ff trimer ground states are nearly indistinguishable. The experimentally determined differences and/or similarities in enthalpies of the complex dissociation reactions are explained by entropic spring effects, which are noticeable in the T4Ff hetero-trimers but not in the T4Ff homo-trimers. A lowering of the transition state energy levels of the T4Ff hetero-trimers seems likely because the biotin moieties, mimicking intrinsically disordered regions (IDRs), induced asymmetries in the transition states of the biotinylated T4Ff hetero-trimers. This transition state energy level lowering effect is absent in the T4Ff homo-trimer, as well as in the triply biotinylated T4Ff homo-trimer. In the latter, the IDR-associated entropic spring effects on complex stability cancel each other out. ITEM-FIVE enabled semi-quantitative determination of energy differences of complex dissociation reactions, whose differences were modulated by IDRs attached to compactly folded proteins.
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Affiliation(s)
- Cornelia Koy
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock Schillingallee 69, 18057 Rostock, Germany; (C.K.)
| | - Claudia Röwer
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock Schillingallee 69, 18057 Rostock, Germany; (C.K.)
| | - Hans-Jürgen Thiesen
- Institute for Immunology, Medical Faculty, University of Rostock, Schillingallee 70, 18057 Rostock, Germany;
| | - Andrei Neamtu
- Department of Physiology, “Gr. T. Popa” University of Medicine and Pharmacy, Str. Universitatii nr. 16, 700115 Iasi, Romania
- TRANSCEND Centre, Regional Institute of Oncology (IRO) Iasi, Str. General Henri Mathias Berthelot, Nr. 2–4, 700483 Iasi, Romania
| | - Michael O. Glocker
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock Schillingallee 69, 18057 Rostock, Germany; (C.K.)
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Adhikari J, Heffernan J, Edeling M, Fernandez E, Jethva PN, Diamond MS, Fremont DH, Gross ML. Epitope Mapping of Japanese Encephalitis Virus Neutralizing Antibodies by Native Mass Spectrometry and Hydrogen/Deuterium Exchange. Biomolecules 2024; 14:374. [PMID: 38540792 PMCID: PMC10967844 DOI: 10.3390/biom14030374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 06/27/2024] Open
Abstract
Japanese encephalitis virus (JEV) remains a global public health concern due to its epidemiological distribution and the existence of multiple strains. Neutralizing antibodies against this infection have shown efficacy in in vivo studies. Thus, elucidation of the epitopes of neutralizing antibodies can aid in the design and development of effective vaccines against different strains of JEV. Here, we describe a combination of native mass spectrometry (native-MS) and hydrogen/deuterium exchange mass spectrometry (HDX-MS) to complete screening of eight mouse monoclonal antibodies (MAbs) against JEV E-DIII to identify epitope regions. Native-MS was used as a first pass to identify the antibodies that formed a complex with the target antigen, and it revealed that seven of the eight monoclonal antibodies underwent binding. Native mass spectra of a MAb (JEV-27) known to be non-binding showed broad native-MS peaks and poor signal, suggesting the protein is a mixture or that there are impurities in the sample. We followed native-MS with HDX-MS to locate the binding sites for several of the complex-forming antibodies. This combination of two mass spectrometry-based approaches should be generally applicable and particularly suitable for screening of antigen-antibody and other protein-protein interactions when other traditional approaches give unclear results or are difficult, unavailable, or need to be validated.
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Affiliation(s)
- Jagat Adhikari
- Department of Chemistry, Washington University in St. Louis, Saint Louis, MO 63130, USA; (J.A.); (P.N.J.)
| | - James Heffernan
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63130, USA; (J.H.); (M.E.); (E.F.); (M.S.D.); (D.H.F.)
| | - Melissa Edeling
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63130, USA; (J.H.); (M.E.); (E.F.); (M.S.D.); (D.H.F.)
| | - Estefania Fernandez
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63130, USA; (J.H.); (M.E.); (E.F.); (M.S.D.); (D.H.F.)
| | - Prashant N. Jethva
- Department of Chemistry, Washington University in St. Louis, Saint Louis, MO 63130, USA; (J.A.); (P.N.J.)
| | - Michael S. Diamond
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63130, USA; (J.H.); (M.E.); (E.F.); (M.S.D.); (D.H.F.)
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63130, USA
- Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, Saint Louis, MO 63130, USA
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63130, USA
| | - Daved H. Fremont
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63130, USA; (J.H.); (M.E.); (E.F.); (M.S.D.); (D.H.F.)
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63130, USA
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, Saint Louis, MO 63130, USA
| | - Michael L. Gross
- Department of Chemistry, Washington University in St. Louis, Saint Louis, MO 63130, USA; (J.A.); (P.N.J.)
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Röwer C, Olaleye OO, Bischoff R, Glocker MO. Mass Spectrometric ITEM-ONE and ITEM-TWO Analyses Confirm and Refine an Assembled Epitope of an Anti-Pertuzumab Affimer. Biomolecules 2023; 14:24. [PMID: 38254624 PMCID: PMC10813730 DOI: 10.3390/biom14010024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/13/2023] [Accepted: 12/21/2023] [Indexed: 01/24/2024] Open
Abstract
Intact Transition Epitope Mapping-One-step Non-covalent force Exploitation (ITEM-ONE) analysis reveals an assembled epitope on the surface of Pertuzumab, which is recognized by the anti-Pertuzumab affimer 00557_709097. It encompasses amino acid residues NSGGSIYNQRFKGR, which are part of CDR2, as well as residues FTLSVDR, which are located on the variable region of Pertuzumab's heavy chain and together form a surface area of 1381.46 Å2. Despite not being part of Pertuzumab's CDR2, the partial sequence FTLSVDR marks a unique proteotypic Pertuzumab peptide. Binding between intact Pertuzumab and the anti-Pertuzumab affimer was further investigated using the Intact Transition Epitope Mapping-Thermodynamic Weak-force Order (ITEM-TWO) approach. Quantitative analysis of the complex dissociation reaction in the gas phase afforded a quasi-equilibrium constant (KD m0g#) of 3.07 × 10-12. The experimentally determined apparent enthalpy (ΔHm0g#) and apparent free energy (ΔGm0g#) of the complex dissociation reaction indicate that the opposite reaction-complex formation-is spontaneous at room temperature. Due to strong binding to Pertuzumab and because of recognizing Pertuzumab's unique partial amino acid sequences, the anti-Pertuzumab affimer 00557_709097 is considered excellently suitable for implementation in Pertuzumab quantitation assays as well as for the accurate therapeutic drug monitoring of Pertuzumab in biological fluids.
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Affiliation(s)
- Claudia Röwer
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, 18057 Rostock, Germany
| | - Oladapo O. Olaleye
- Department of Analytical Biochemistry, Faculty of Science & Engineering, University of Groningen, 9713 AV Groningen, The Netherlands
| | - Rainer Bischoff
- Department of Analytical Biochemistry, Faculty of Science & Engineering, University of Groningen, 9713 AV Groningen, The Netherlands
| | - Michael O. Glocker
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, 18057 Rostock, Germany
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Lupu L, Kleinekofort W, Morgner N. Epitope characterization of proteins and aptamers with mass spectrometry. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2023; 29:359-369. [PMID: 37957929 DOI: 10.1177/14690667231208530] [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: 11/15/2023]
Abstract
The way in which professor Michael Przybylski has combined the spirit of research with entrepreneurship has set an example for any and all scientists. He has made significant achievements in the fields of mass spectrometry, biochemistry and medicine, and has initiated important technological developments in the area of protein analysis. Between 2016 and 2023 professor Przybylski's scientific focus shifted on protein interactions with emphasis on aptamer-protein and antibody-protein analysis. This review focuses on professor Przybylski's achievements in the last few years highlighting his impact on the scientific community, on his students and colleagues.
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Affiliation(s)
- Loredana Lupu
- AffyMSLifeChem Centre for Analytical Biochemistry and Biomedical Mass Spectrometry, Rüsselsheim am Main, Germany
| | | | - Nina Morgner
- Institut für Physikalische und Theoretische Chemie, Goethe-Universität Frankfurt am Main, Frankfurt Am Main, Germany
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Koy C, Glocker UM, Danquah BD, Glocker MO. Native and compactly folded in-solution conformers of pepsin are revealed and distinguished by mass spectrometric ITEM-TWO analyses of gas-phase pepstatin A - pepsin complex binding strength differences. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2023; 29:303-312. [PMID: 37259551 DOI: 10.1177/14690667231178999] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Pepsin, because of its optimal activity at low acidic pH, has gained importance in mass spectrometric proteome research as a readily available and easy-to-handle protease. Pepsin has also been study object of protein higher-order structure analyses, but questions about how to best investigate pepsin in-solution conformers still remain. We first determined dependencies of pepsin ion charge structures on solvent pH which indicated the in-solution existence of (a) natively folded pepsin (N) which by nanoESI-MS analysis gave rise to a narrow charge state distribution with an 11-fold protonated most intense ion signal, (b) unfolded pepsin (U) with a rather broad ion charge state distribution whose highest ion signal carried 25 protons, and (c) a compactly folded pepsin conformer (C) with a narrow charge structure and a 12-fold protonated ion signal in the center of its charge state envelope. Because pepsin is a protease, unfolded pepsin became its own substrate in solution at pH 6.6 since at this pH some portion of pepsin maintained a compact/native fold which displayed enzymatic activity. Subsequent mass spectrometric ITEM-TWO analyses of pepstatin A - pepsin complex dissociation reactions in the gas phase confirmed a very strong binding of pepstatin A by natively folded pepsin (N). ITEM-TWO further revealed the existence of two compactly folded in-solution pepsin conformers (Ca and Cb) which also were able to bind pepstatin A. Binding strengths of the respective compactly folded pepsin conformer-containing complexes could be determined and apparent gas phase complex dissociation constants and reaction enthalpies differentiated these from each other and from the pepstatin A - pepsin complex which had been formed from natively folded pepsin. Thus, ITEM-TWO turned out to be well suited to pinpoint in-solution pepsin conformers by interrogating quantitative traits of pepstatin A - pepsin complexes in the gas phase.
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Affiliation(s)
- Cornelia Koy
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
| | - Ursula M Glocker
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
| | - Bright D Danquah
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
| | - Michael O Glocker
- Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
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Jethva PN, Gross ML. Hydrogen Deuterium Exchange and other Mass Spectrometry-based Approaches for Epitope Mapping. FRONTIERS IN ANALYTICAL SCIENCE 2023; 3:1118749. [PMID: 37746528 PMCID: PMC10512744 DOI: 10.3389/frans.2023.1118749] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Antigen-antibody interactions are a fundamental subset of protein-protein interactions responsible for the "survival of the fittest". Determining the interacting interface of the antigen, called an epitope, and that on the antibody, called a paratope, is crucial to antibody development. Because each antigen presents multiple epitopes (unique footprints), sophisticated approaches are required to determine the target region for a given antibody. Although X-ray crystallography, Cryo-EM, and nuclear magnetic resonance can provide atomic details of an epitope, they are often laborious, poor in throughput, and insensitive. Mass spectrometry-based approaches offer rapid turnaround, intermediate structural resolution, and virtually no size limit for the antigen, making them a vital approach for epitope mapping. In this review, we describe in detail the principles of hydrogen deuterium exchange mass spectrometry in application to epitope mapping. We also show that a combination of MS-based approaches can assist or complement epitope mapping and push the limit of structural resolution to the residue level. We describe in detail the MS methods used in epitope mapping, provide our perspective about the approaches, and focus on elucidating the role that HDX-MS is playing now and in the future by organizing a discussion centered around several improvements in prototype instrument/applications used for epitope mapping. At the end, we provide a tabular summary of the current literature on HDX-MS-based epitope mapping.
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Affiliation(s)
- Prashant N. Jethva
- Department of Chemistry, Washington University in St. Louis, St Louis, MO 63130, USA
| | - Michael L. Gross
- Department of Chemistry, Washington University in St. Louis, St Louis, MO 63130, USA
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Zammataro A, Koy C, Ruß M, Röwer C, Glocker MO. Intact Transition Epitope Mapping—Serological Inspection by Epitope EXtraction (ITEM—SIX). Molecules 2023; 28:molecules28073092. [PMID: 37049857 PMCID: PMC10096252 DOI: 10.3390/molecules28073092] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/27/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023] Open
Abstract
Precision medicine requests accurate serological inspections to precisely stratify patients for targeted treatment. Intact transition epitope mapping analysis proved surrogate seroconversion of a model organism’s serum when spiked with a monoclonal murine anti-Ovalbumin antibody (mAb) with epitope resolution. Isolation of the IgG fraction from blood serum applied two consecutive protein precipitation steps followed by ultrafiltration and resulted in an ESI-MS analysis-ready IgG preparation. For epitope mapping by epitope extraction, the Ovalbumin antigen was digested with trypsin. After desalting, the peptide mixture was added to the ESI-MS-ready IgG preparation from mAb-spiked serum and the solution was incubated to form an immune complex between the Ovalbumin-derived epitope peptide and the anti-Ovalbumin mAb. Then, the entire mixture of proteins and peptides was directly electrosprayed. Sorting of ions in the mass spectrometer’s gas phase, dissociation of the immune complex ions by collision-induced dissociation, and recording of the epitope peptide ion that had been released from the immune complex proved the presence of the anti-Ovalbumin mAb in serum. Mass determination of the complex-released epitope peptide ion with isotope resolution is highly accurate, guaranteeing high specificity of this novel analysis approach, which is termed Intact Transition Epitope Mapping—Serological Inspections by Epitope EXtraction (ITEM—SIX).
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Scherf M, Koy C, Röwer C, Neamtu A, Glocker MO. Characterization of Phosphorylation-Dependent Antibody Binding to Cancer-Mutated Linkers of C 2H 2 Zinc Finger Proteins by Intact Transition Epitope Mapping-Thermodynamic Weak-Force Order Analysis. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:171-181. [PMID: 36656134 DOI: 10.1021/jasms.2c00244] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
With Intact Transition Epitope Mapping-Thermodynamic Weak-force Order (ITEM-TWO) analysis in combination with molecular modeling, the phosphorylation-dependent molecular recognition motif of the anti-HpTGEKP antibody has been investigated with binary and ternary component mixtures consisting of antibody and (phospho-) peptides. Amino acid sequences have been selected to match either the antibody's recognition motif or the cancer-related zinc finger protein mutations and phosphorylations of the respective amino acid residues. Upon electrospraying of all the components of the mixtures, that is, hexapeptides, antibody, and intact immune complexes, the produced ions were subjected to mass spectrometric mass filtering. The antibody ions as well as the immune complex ions traversed into the mass spectrometer's collision chamber, whereas paths of unbound peptide ions were blocked prior to entering the collision cell. After dissociation of the multiply charged immune complexes in the gas phase, the complex-released peptide ions were recorded after having traversed the second mass filter. Complex-released peptides were unambiguously identified by their masses using mass analysis with isotope resolution. From the results of our studies with seven (phospho-) peptides with distinct amino acid sequences, which resembled either the antibody's binding motif or mutations, we conclude the following: (i) A negatively charged phospho group, located near the peptide's N-terminus is mandatory for antibody binding when placed on the peptide surface at a precise distance to the C-terminally located positively charged ε-amino group of a lysinyl residue. (ii) A bulky amino acid residue, such as the tyrosinyl residue at the N-terminal position of the (phospho-) threoninyl residue, abolishes antibody binding. (iii) Two closely spaced phospho groups negatively interfere with the surface polarity pattern and abolish antibody binding as well. (iv) Non-phosphorylated peptides are not binding partners of the anti-HpTGEKP antibody.
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Affiliation(s)
- Maximilian Scherf
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18059 Rostock, Germany
| | - Cornelia Koy
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18059 Rostock, Germany
| | - Claudia Röwer
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18059 Rostock, Germany
| | - Andrei Neamtu
- TRANSCEND Centre, Regional Institute of Oncology (IRO) Iasi, Str. General Henri Mathias Berthelot Nr. 2-4, 700483 Iasi, Romania
- Department of Physiology, Grigore T. Popa University of Medicine and Pharmacy of Iasi, Str. Universitatii Nr. 16, 700115 Iasi, Romania
| | - Michael O Glocker
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18059 Rostock, Germany
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Intact Transition Epitope Mapping-Force Differences between Original and Unusual Residues (ITEM-FOUR). Biomolecules 2023; 13:biom13010187. [PMID: 36671572 PMCID: PMC9856199 DOI: 10.3390/biom13010187] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/06/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Antibody-based point-of-care diagnostics have become indispensable for modern medicine. In-depth analysis of antibody recognition mechanisms is the key to tailoring the accuracy and precision of test results, which themselves are crucial for targeted and personalized therapy. A rapid and robust method is desired by which binding strengths between antigens and antibodies of concern can be fine-mapped with amino acid residue resolution to examine the assumedly serious effects of single amino acid polymorphisms on insufficiencies of antibody-based detection capabilities of, e.g., life-threatening conditions such as myocardial infarction. The experimental ITEM-FOUR approach makes use of modern mass spectrometry instrumentation to investigate intact immune complexes in the gas phase. ITEM-FOUR together with molecular dynamics simulations, enables the determination of the influences of individually exchanged amino acid residues within a defined epitope on an immune complex's binding strength. Wild-type and mutated epitope peptides were ranked according to their experimentally determined dissociation enthalpies relative to each other, thereby revealing which single amino acid polymorphism caused weakened, impaired, and even abolished antibody binding. Investigating a diagnostically relevant human cardiac Troponin I epitope for which seven nonsynonymous single nucleotide polymorphisms are known to exist in the human population tackles a medically relevant but hitherto unsolved problem of current antibody-based point-of-care diagnostics.
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Scherf M, Danquah BD, Koy C, Lorenz P, Steinbeck F, Neamtu A, Thiesen H, Glocker MO. Epitope Fine Mapping by Mass Spectrometry: Investigations of Immune Complexes Consisting of Monoclonal Anti-HpTGEKP Antibody and Zinc Finger Protein Linker Phospho-Hexapeptides. Chembiochem 2022; 23:e202200390. [PMID: 35950614 PMCID: PMC9826235 DOI: 10.1002/cbic.202200390] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/03/2022] [Indexed: 01/11/2023]
Abstract
Accurate formation of antibody-antigen complexes has been relied on in both, multitudes of scientific projects and ample therapeutic and diagnostic applications. Mass spectrometrically determined dissociation behavior of immune complexes with the anti-HpTGEKP antibody revealed that the ten most frequently occurring phospho-hexapeptide linker sequences from C2H2 zinc finger proteins could be divided into two classes: orthodox binders, where strong noncovalent interactions developed as anticipated, and unorthodox binders with deviating structures and weaker binding. Phosphorylation of threonine was compulsory for antibody binding in an orthodox manner. Gas phase dissociation energy determinations of seven C2H2 zinc finger protein linker phospho-hexapeptides with orthodox binding properties revealed a bipolar binding motif of the antibody paratope. Epitope peptides, which in addition to the negatively charged phospho-threonine residue were C-terminally flanked by positively charged residues provided stronger binding, i. e. dissociation was endothermic, than peptides with acidic amino acid residues at these positions, for which dissociation was exothermic.
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Affiliation(s)
- Maximilian Scherf
- Proteome Center RostockUniversity Medicine Rostock and University of RostockSchillingallee 6918059RostockGermany
| | - Bright D. Danquah
- Proteome Center RostockUniversity Medicine Rostock and University of RostockSchillingallee 6918059RostockGermany
| | - Cornelia Koy
- Proteome Center RostockUniversity Medicine Rostock and University of RostockSchillingallee 6918059RostockGermany
| | - Peter Lorenz
- Institute of ImmunologyUniversity Medicine RostockSchillingallee 7018059RostockGermany
| | - Felix Steinbeck
- Institute of ImmunologyUniversity Medicine RostockSchillingallee 7018059RostockGermany,Gesellschaft für Individualisierte Medizin mbH (IndyMed)Industriestrasse 1518069RostockGermany
| | - Andrei Neamtu
- Department of PhysiologyGr. T. Popa University of Medicine and Pharmacy of IasiStr. Universitatii nr. 16Iasi Jud.Romania
| | - Hans‐Jürgen Thiesen
- Institute of ImmunologyUniversity Medicine RostockSchillingallee 7018059RostockGermany,Gesellschaft für Individualisierte Medizin mbH (IndyMed)Industriestrasse 1518069RostockGermany
| | - Michael O. Glocker
- Proteome Center RostockUniversity Medicine Rostock and University of RostockSchillingallee 6918059RostockGermany
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Koy C, Opuni KFM, Danquah BD, Neamtu A, Glocker MO. Mass Spectrometric and Bio-Computational Binding Strength Analysis of Multiply Charged RNAse S Gas-Phase Complexes Obtained by Electrospray Ionization from Varying In-Solution Equilibrium Conditions. Int J Mol Sci 2021; 22:ijms221910183. [PMID: 34638522 PMCID: PMC8508491 DOI: 10.3390/ijms221910183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 11/18/2022] Open
Abstract
We investigated the influence of a solvent’s composition on the stability of desorbed and multiply charged RNAse S ions by analyzing the non-covalent complex’s gas-phase dissociation processes. RNAse S was dissolved in electrospray ionization-compatible buffers with either increasing organic co-solvent content or different pHs. The direct transition of all the ions and the evaporation of the solvent from all the in-solution components of RNAse S under the respective in-solution conditions by electrospray ionization was followed by a collision-induced dissociation of the surviving non-covalent RNAse S complex ions. Both types of changes of solvent conditions yielded in mass spectrometrically observable differences of the in-solution complexation equilibria. Through quantitative analysis of the dissociation products, i.e., from normalized ion abundances of RNAse S, S-protein, and S-peptide, the apparent kinetic and apparent thermodynamic gas-phase complex properties were deduced. From the experimental data, it is concluded that the stability of RNAse S in the gas phase is independent of its in-solution equilibrium but is sensitive to the complexes’ gas-phase charge states. Bio-computational in-silico studies showed that after desolvation and ionization by electrospray, the remaining binding forces kept the S-peptide and S-protein together in the gas phase predominantly by polar interactions, which indirectly stabilized the in-bulk solution predominating non-polar intermolecular interactions. As polar interactions are sensitive to in-solution protonation, bio-computational results provide an explanation of quantitative experimental data with single amino acid residue resolution.
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Affiliation(s)
- Cornelia Koy
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18057 Rostock, Germany; (C.K.); (K.F.M.O.); (B.D.D.)
| | - Kwabena F. M. Opuni
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18057 Rostock, Germany; (C.K.); (K.F.M.O.); (B.D.D.)
- Department of Pharmaceutical Chemistry, School of Pharmacy, College of Health Science, University of Ghana, P.O. Box LG43, Legon, Ghana
| | - Bright D. Danquah
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18057 Rostock, Germany; (C.K.); (K.F.M.O.); (B.D.D.)
| | - Andrei Neamtu
- Department of Physiology, Grigore T. Popa University of Medicine and Pharmacy of Iasi, Str. Universitatii nr. 16, 700051 Iasi, Romania;
| | - Michael O. Glocker
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Schillingallee 69, 18057 Rostock, Germany; (C.K.); (K.F.M.O.); (B.D.D.)
- Correspondence: ; Tel.: +49-381-494-4930; Fax: +49-381-494-4932
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Mass Spectrometric Analysis of Antibody-Epitope Peptide Complex Dissociation: Theoretical Concept and Practical Procedure of Binding Strength Characterization. Molecules 2020; 25:molecules25204776. [PMID: 33080923 PMCID: PMC7587528 DOI: 10.3390/molecules25204776] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/09/2020] [Accepted: 10/16/2020] [Indexed: 12/02/2022] Open
Abstract
Electrospray mass spectrometry is applied to determine apparent binding energies and quasi equilibrium dissociation constants of immune complex dissociation reactions in the gas phase. Myoglobin, a natural protein-ligand complex, has been used to develop the procedure which starts from determining mean charge states and normalized and averaged ion intensities. The apparent dissociation constant KD m0g#= 3.60 × 10−12 for the gas phase heme dissociation process was calculated from the mass spectrometry data and by subsequent extrapolation to room temperature to mimic collision conditions for neutral and resting myoglobin. Similarly, for RNAse S dissociation at room temperature a KD m0g#= 4.03 × 10−12 was determined. The protocol was tested with two immune complexes consisting of epitope peptides and monoclonal antibodies. For the epitope peptide dissociation reaction of the FLAG peptide from the antiFLAG antibody complex an apparent gas phase dissociation constant KD m0g#= 4.04 × 10−12 was calculated. Likewise, an apparent KD m0g#= 4.58 × 10−12 was calculated for the troponin I epitope peptide—antiTroponin I antibody immune complex dissociation. Electrospray mass spectrometry is a rapid method, which requires small sample amounts for either identification of protein-bound ligands or for determination of the apparent gas phase protein-ligand complex binding strengths.
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Barth M, Schmidt C. Native mass spectrometry-A valuable tool in structural biology. JOURNAL OF MASS SPECTROMETRY : JMS 2020; 55:e4578. [PMID: 32662584 DOI: 10.1002/jms.4578] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 05/16/2023]
Abstract
Proteins and the complexes they form with their ligands are the players of cellular action. Their function is directly linked with their structure making the structural analysis of protein-ligand complexes essential. Classical techniques of structural biology include X-ray crystallography, nuclear magnetic resonance spectroscopy and recently distinguished cryo-electron microscopy. However, protein-ligand complexes are often dynamic and heterogeneous and consequently challenging for these techniques. Alternative approaches are therefore needed and gained importance during the last decades. One alternative is native mass spectrometry, which is the analysis of intact protein complexes in the gas phase. To achieve this, sample preparation and instrument conditions have to be optimised. Native mass spectrometry then reveals stoichiometry, protein interactions and topology of protein assemblies. Advanced techniques such as ion mobility and high-resolution mass spectrometry further add to the range of applications and deliver information on shape and microheterogeneity of the complexes. In this tutorial, we explain the basics of native mass spectrometry including sample requirements, instrument modifications and interpretation of native mass spectra. We further discuss the developments of native mass spectrometry and provide example spectra and applications.
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Affiliation(s)
- Marie Barth
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Institute for Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Carla Schmidt
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Institute for Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle, Germany
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14
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Memory-Enhancing Effects of Origanum majorana Essential Oil in an Alzheimer's Amyloid beta1-42 Rat Model: A Molecular and Behavioral Study. Antioxidants (Basel) 2020; 9:antiox9100919. [PMID: 32993114 PMCID: PMC7600529 DOI: 10.3390/antiox9100919] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/23/2020] [Accepted: 09/24/2020] [Indexed: 12/18/2022] Open
Abstract
Origanum L. (Lamiaceae) is an important genus of medicinal and aromatic plants used in traditional medicine since ancient times as culinary herbs and remedies. The aim of the present study was to evaluate the chemical composition, as well as the biochemical and cellular activities of freshly prepared Origanum majorana L. essential oil (OmEO) in an Alzheimer’s disease (AD) amyloid beta1-42 (Aβ1-42) rat model. OmEO (1% and 3%) was inhaled for 21 consecutive days, while Aβ1-42 was administered intracerebroventricularly to induce AD-like symptoms. Our data demonstrate that OmEO increased antioxidant activity and enhanced brain-derived neurotrophic factor (BDNF) expression, which in concert contributed to the improvement of cognitive function of animals. Moreover, OmEO presented beneficial effects on memory performance in Y-maze and radial arm-maze tests in the Aβ1-42 rat AD model.
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15
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Opuni KFM, Koy C, Russ M, Reepmeyer M, Danquah BD, Weresow M, Alef A, Lorenz P, Thiesen HJ, Glocker MO. ITEM-THREE analysis of a monoclonal anti-malaria antibody reveals its assembled epitope on the pfMSP1 19 antigen. J Biol Chem 2020; 295:14987-14997. [PMID: 32848020 DOI: 10.1074/jbc.ra120.014802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/18/2020] [Indexed: 11/06/2022] Open
Abstract
Rapid diagnostic tests are first-line assays for diagnosing infectious diseases, such as malaria. To minimize false positive and false negative test results in population-screening assays, high-quality reagents and well-characterized antigens and antibodies are needed. An important property of antigen-antibody binding is recognition specificity, which best can be estimated by mapping an antibody's epitope on the respective antigen. We have cloned a malarial antigen-containing fusion protein, MBP-pfMSP119, in Escherichia coli, which then was structurally and functionally characterized before and after high pressure-assisted enzymatic digestion. We then used our previously developed method, intact transition epitope mapping-targeted high-energy rupture of extracted epitopes (ITEM-THREE), to map the area on the MBP-pfMSP119 antigen surface that is recognized by the anti-pfMSP119 antibody G17.12. We identified three epitope-carrying peptides, 386GRNISQHQCVKKQCPQNSGCFRHLDE411, 386GRNISQHQCVKKQCPQNSGCFRHLDEREE414, and 415CKCLLNYKQE424, from the GluC-derived peptide mixture. These peptides belong to an assembled (conformational) epitope on the MBP-pfMSP119 antigen whose identification was substantiated by positive and negative control experiments. In conclusion, our data help to establish a workflow to obtain high-quality control data for diagnostic assays, including the use of ITEM-THREE as a powerful analytical tool. Data are available via ProteomeXchange: PXD019717.
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Affiliation(s)
- Kwabena F M Opuni
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Rostock, Germany; Department of Pharmaceutical Chemistry, School of Pharmacy, College of Health, University of Ghana, Legon, Ghana
| | - Cornelia Koy
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Rostock, Germany
| | - Manuela Russ
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Rostock, Germany
| | - Maren Reepmeyer
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Rostock, Germany
| | - Bright D Danquah
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Rostock, Germany
| | | | | | - Peter Lorenz
- Institute for Immunology, University Medicine Rostock, Rostock, Germany
| | | | - Michael O Glocker
- Proteome Center Rostock, University Medicine Rostock and University of Rostock, Rostock, Germany.
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16
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Howlett DR, Clarke IJ, Newton RP, Hart JE. Epitope mapping of an uncertain endogenous antigen implies secretogranin II peptide splicing. F1000Res 2019; 8:1732. [PMID: 32399184 PMCID: PMC7194351 DOI: 10.12688/f1000research.20633.2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/25/2019] [Indexed: 11/20/2022] Open
Abstract
Background: The search for a tissue-mass reducing reproductive hormone involved a bioassay-guided physicochemical fractionation of sheep blood plasma. This brought forth a candidate protein whose apparent mass on gels and in mass spectrometry (MS) was 7-8 kDa, implying a polypeptide of ~70 residues. Four purification runs gave Edman N-terminal sequences relating to 1MKPLTGKVKEFNNI 14. This is bioinformatically obscure and has been resistant to molecular biological investigation. The sequence was synthesized as the peptide EPL001, against which was raised a goat polyclonal antiserum, G530. Used in an antigen capture campaign, G530 pointed to the existence of a novel derivative of secretogranin II (SgII), the neuroendocrine secretory vesicle helper protein and prohormone. The proposed SgII derivative was dubbed SgII-70, yet the sequence commonality between SgII and EPL001 is essentially NNI. Methods: Immunohistochemical (IHC) labelling with G530 is reported within rat, mouse and human cerebrovasculature and in glandular elements of the mouse intestine. Epitope mapping involved IHC peptide preabsorption, allied to deductive bioinformatics and molecular modelling in silico. Results: G530 is deemed monoepitopic in regard to both its synthetic antigen (EPL001) and its putative endogenous antigen (SgII related). The epitope within EPL001 of the anti-EPL001 antibody is inferred to be the contiguous C-terminal 9KEFNNI 14. This is so because the G530 blockade data are consistent with the epitope in the mammalian endogenous antigen being part contiguous, part non-contiguous KE·F·NNI, ex hypothesi. The observed immunostaining is deduced to be due to pre-SgII-70, which has a non-C-terminal NNI, and SgII-70, which has an N-terminal MLKTGEKPV/N and a C-terminal NNI (these two motifs being in the reverse order in the SgII parent protein). Conclusion: The present data are consistent with the hypothesis that the anti-EPL001 antibody binds to an SgII-related epitope. SgII is apparently subject to peptide splicing, as has been reported for the related chromogranin A.
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Affiliation(s)
- David R. Howlett
- Wolfson Centre for Age Related Disease, Kings College London, London, SE1 1UL, UK,
| | - Iain J. Clarke
- School of Agriculture and Veterinary Science, Melbourne University, Parkville, Victoria, VIC 3010, Australia
| | - Russell P. Newton
- Biochemistry Group, Institute of Life Sciences, Medical School, Swansea University, Swansea, Wales, SA2 8PP, UK
| | - John E. Hart
- Endocrine Pharmaceuticals Ltd, Tadley, Hampshire, RG26 3TA, UK
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Danquah BD, Yefremova Y, Opuni KFM, Röwer C, Koy C, Glocker MO. Intact Transition Epitope Mapping - Thermodynamic Weak-force Order (ITEM - TWO). J Proteomics 2019; 212:103572. [PMID: 31683061 DOI: 10.1016/j.jprot.2019.103572] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/25/2019] [Accepted: 10/27/2019] [Indexed: 01/17/2023]
Abstract
We have developed an electrospray mass spectrometry method which is capable to determine antibody affinity in a gas phase experiment. A solution with the immune complex is electrosprayed and multiply charged ions are translated into the gas phase. Then, the intact immune-complex ions are separated from unbound peptide ions. Increasing the voltage difference in a collision cell results in collision induced dissociation of the immune-complex by which bound peptide ions are released. When analyzing a peptide mixture, measuring the mass of the complex-released peptide ions identifies which of the peptides contains the epitope. A step-wise increase in the collision cell voltage difference changes the intensity ratios of the surviving immune complex ions, the released peptide ions, and the antibody ions. From all the ions´ normalized intensity ratios are deduced the thermodynamic quasi equilibrium dissociation constants (KDm0g#) from which are calculated the apparent gas phase Gibbs energies of activation over temperature (ΔGm0g#T). The order of the apparent gas phase dissociation constants of four antibody - epitope peptide pairs matched well with those obtained from in-solution measurements. The determined gas phase values for antibody affinities are independent from the source of the investigated peptides and from the applied instrument. Data are available via ProteomeXchange with identifier PXD016024. SIGNIFICANCE: ITEM - TWO enables rapid epitope mapping and determination of apparent dissociation energies of immune complexes with minimal in-solution handling. Mixing of antibody and antigen peptide solutions initiates immune complex formation in solution. Epitope binding strengths are determined in the gas phase after electrospraying the antibody / antigen peptide mixtures and mass spectrometric analysis of immune complexes under different collision induced dissociation conditions. Since the order of binding strengths in the gas phase is the same as that in solution, ITEM - TWO characterizes two most important antibody properties, specificity and affinity.
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Affiliation(s)
- Bright D Danquah
- Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | - Yelena Yefremova
- Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | | | - Claudia Röwer
- Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | - Cornelia Koy
- Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | - Michael O Glocker
- Proteome Center Rostock, University Medicine Rostock, Rostock, Germany.
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18
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Danquah BD, Röwer C, Opuni KM, El-Kased R, Frommholz D, Illges H, Koy C, Glocker MO. Intact Transition Epitope Mapping - Targeted High-Energy Rupture of Extracted Epitopes (ITEM-THREE). Mol Cell Proteomics 2019; 18:1543-1555. [PMID: 31147491 PMCID: PMC6683010 DOI: 10.1074/mcp.ra119.001429] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/14/2019] [Indexed: 12/31/2022] Open
Abstract
Epitope mapping, which is the identification of antigenic determinants, is essential for the design of novel antibody-based therapeutics and diagnostic tools. ITEM-THREE is a mass spectrometry-based epitope mapping method that can identify epitopes on antigens upon generating an immune complex in electrospray-compatible solutions by adding an antibody of interest to a mixture of peptides from which at least one holds the antibody's epitope. This mixture is nano-electrosprayed without purification. Identification of the epitope peptide is performed within a mass spectrometer that provides an ion mobility cell sandwiched in-between two collision cells and where this ion manipulation setup is flanked by a quadrupole mass analyzer on one side and a time-of-flight mass analyzer on the other side. In a stepwise fashion, immune-complex ions are separated from unbound peptide ions and dissociated to release epitope peptide ions. Immune complex-released peptide ions are separated from antibody ions and fragmented by collision induced dissociation. Epitope-containing peptide fragment ions are recorded, and mass lists are submitted to unsupervised data base search thereby retrieving both, the amino acid sequence of the epitope peptide and the originating antigen. ITEM-THREE was developed with antiTRIM21 and antiRA33 antibodies for which the epitopes were known, subjecting them to mixtures of synthetic peptides of which one contained the respective epitope. ITEM-THREE was then successfully tested with an enzymatic digest of His-tagged recombinant human β-actin and an antiHis-tag antibody, as well as with an enzymatic digest of recombinant human TNFα and an antiTNFα antibody whose epitope was previously unknown.
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Affiliation(s)
- Bright D Danquah
- ‡Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | - Claudia Röwer
- ‡Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | | | - Reham El-Kased
- ¶Microbiology and Immunology Faculty of Pharmacy, The British University in Egypt, Cairo, Egypt
| | - David Frommholz
- ‖University of Applied Sciences Bonn-Rhein-Sieg, Immunology and Cell Biology, Rheinbach, Germany
| | - Harald Illges
- ‖University of Applied Sciences Bonn-Rhein-Sieg, Immunology and Cell Biology, Rheinbach, Germany;; **University of Applied Sciences Bonn-Rhein-Sieg, Institute for Functional Gene Analytics, Rheinbach, Germany
| | - Cornelia Koy
- ‡Proteome Center Rostock, University Medicine Rostock, Rostock, Germany
| | - Michael O Glocker
- ‡Proteome Center Rostock, University Medicine Rostock, Rostock, Germany.
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19
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Wölter M, Russ M, Okai CA, Rath W, Pecks U, Glocker MO. Comparison of blood serum protein analysis by MALDI-MS from either conventional frozen samples or storage disc-deposited samples: A study with human serum from pregnant donors and from patients with intrauterine growth restriction. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2019; 25:381-390. [PMID: 30587036 DOI: 10.1177/1469066718820991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Mass spectrometric profiling of intact serum proteins, i.e. determination of relative protein abundance differences, was performed using two different serum sample preparation methods: one with frozen and thawed serum, the other with at room temperature deposited and dried serum. Since in a typical clinical setting freezing of serum is difficult to achieve, sampling at room temperature is preferred and can be met when using the Noviplex™ card system. Once deposited and dried, serum proteins can be stored and shipped at room temperature. After resolubilization of serum proteins from "dried serum spots", mass spectra of high quality have been recorded comparable to those that were obtained using fresh-frozen and subsequently thawed serum samples. Differentiation between patients with intrauterine growth restriction and control individuals was achievable, independent from the sample work-up procedure. Having at hand a reliable and robust method for serum storage and shipment which works at room temperature bridges the gap between the clinics and the protein analysis laboratory. Our novel serum handling protocol reduces costs for both, storage and shipping, and ultimately enables clinical risk assessment based on mass spectrometric determination of intact protein abundance profiles.
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Affiliation(s)
- Manja Wölter
- 1 Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
| | - Manuela Russ
- 1 Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
| | - Charles A Okai
- 1 Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
| | - Werner Rath
- 2 Department of Obstetrics and Gynecology, University of Schleswig-Holstein, Kiel, Germany
| | - Ulrich Pecks
- 2 Department of Obstetrics and Gynecology, University of Schleswig-Holstein, Kiel, Germany
| | - Michael O Glocker
- 1 Proteome Center Rostock, Medical Faculty and Natural Science Faculty, University of Rostock, Rostock, Germany
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Ştefănescu R, Stanciu GD, Luca A, Caba IC, Tamba BI, Mihai CT. Contributions of Mass Spectrometry to the Identification of Low Molecular Weight Molecules Able to Reduce the Toxicity of Amyloid-β Peptide to Cell Cultures and Transgenic Mouse Models of Alzheimer's Disease. Molecules 2019; 24:E1167. [PMID: 30909659 PMCID: PMC6471768 DOI: 10.3390/molecules24061167] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 03/22/2019] [Accepted: 03/22/2019] [Indexed: 11/16/2022] Open
Abstract
Alzheimer's Disease affects approximately 33 million people worldwide and is characterized by progressive loss of memory at the cognitive level. The formation of toxic amyloid oligomers, extracellular amyloid plaques and amyloid angiopathy in brain by amyloid beta peptides are considered a part of the identified mechanism involved in disease pathogenesis. The optimal treatment approach leads toward finding a chemical compound able to form a noncovalent complex with the amyloid peptide thus blocking the process of amyloid aggregation. This direction gained an increasing interest lately, many studies demonstrating that mass spectrometry is a valuable method useful for the identification and characterization of such molecules able to interact with amyloid peptides. In the present review we aim to identify in the scientific literature low molecular weight chemical compounds for which there is mass spectrometric evidence of noncovalent complex formation with amyloid peptides and also there are toxicity reduction results which verify the effects of these compounds on amyloid beta toxicity towards cell cultures and transgenic mouse models developing Alzheimer's Disease.
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Affiliation(s)
- Raluca Ştefănescu
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universității Street, 700115 Iaşi, Romania.
| | - Gabriela Dumitriṭa Stanciu
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universității Street, 700115 Iaşi, Romania.
| | - Andrei Luca
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universității Street, 700115 Iaşi, Romania.
| | - Ioana Cezara Caba
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universității Street, 700115 Iaşi, Romania.
- Faculty of Pharmacy, "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universităṭii Street, 700115 Iaşi, Romania.
| | - Bogdan Ionel Tamba
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universității Street, 700115 Iaşi, Romania.
| | - Cosmin Teodor Mihai
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), "Grigore T. Popa" University of Medicine and Pharmacy, 16 Universității Street, 700115 Iaşi, Romania.
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21
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Ion L, Petre BA. Immuno-Affinity Mass Spectrometry: A Novel Approaches with Biomedical Relevance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1140:377-388. [DOI: 10.1007/978-3-030-15950-4_21] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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22
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Ben-Nissan G, Sharon M. The application of ion-mobility mass spectrometry for structure/function investigation of protein complexes. Curr Opin Chem Biol 2018; 42:25-33. [PMID: 29128665 PMCID: PMC5796646 DOI: 10.1016/j.cbpa.2017.10.026] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 10/19/2017] [Accepted: 10/24/2017] [Indexed: 12/16/2022]
Abstract
Ion-mobility mass spectrometry (IM-MS) is an approach that can provide information on the stoichiometry, composition, protein contacts and topology of protein complexes. The power of this approach lies not only in its sensitivity and speed of analysis, but also in the fact that it is a technique that can capture the repertoire of conformational states adopted by protein assemblies. Here, we describe the array of available IM-MS based tools, and demonstrate their application to the structural characterization of various protein complexes, including challenging systems as amyloid aggregates and membrane proteins. We also discuss recent studies in which IM-MS was applied towards investigations of conformational transitions and stabilization effects induced by protein interactions.
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Affiliation(s)
- Gili Ben-Nissan
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Michal Sharon
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
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