1
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Prell JS. Modeling collisional kinetic energy damping, heating, and cooling of ions in mass spectrometers: a tutorial perspective. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2024; 504:117290. [PMID: 39072228 PMCID: PMC11271708 DOI: 10.1016/j.ijms.2024.117290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Many powerful methods in mass spectrometry rely on activation of ions by high-energy collisions with gas particles. For example, multiple Collision Induced Dissociation (CID) has been used for many years to determine structural information for ions ranging from small organics to large, native-like protein complexes. More recently, Collision Induced Unfolding (CIU) has proved to be a very powerful method for understanding high-order protein structure and detecting differences between similar proteins. Quantifying the thermochemistry underlying dissociation/unfolding in these experiments can be quite challenging without reliable models of ion heating and cooling. Established physical models of CID are valuable in predicting ion heating but do not explicitly include mechanisms for cooling, which may play a large part in CID/CIU in modern instruments. Ab initio and Molecular Dynamics methods are extremely computationally expensive for modeling CID/CIU of large analytes such as biomolecular ions. In this tutorial perspective, limiting behaviors of ion kinetic energy damping, heating, and cooling set by "extreme" cases are explored, and an Improved Impulsive Collision Theory and associated software ("Ion Simulations of the Physics of Activation", IonSPA) are introduced that can model all of these for partially inelastic collisions. Finally, examples of modeled collisional activation of native-like protein ions under realistic experimental conditions are discussed, with an outlook toward the use of IonSPA in accessing the thermochemical information hidden in CID breakdown curves and CIU fingerprints.
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Affiliation(s)
- James S. Prell
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene, OR, USA, 97403-1253
- Materials Science Institute, 1252 University of Oregon, OR, USA, 97403-1252
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2
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Zhang J, Phetsanthad A, Li L. Investigating Anion Effects on Metal Ion Binding Interactions With Amyloid β Peptide by Ion Mobility Mass Spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2024; 59:e5090. [PMID: 39328006 PMCID: PMC11446473 DOI: 10.1002/jms.5090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 07/22/2024] [Accepted: 07/31/2024] [Indexed: 09/28/2024]
Abstract
The study of metal ion's role in the biological processes of Alzheimer's disease has spurred investigations into the coordination chemistry of amyloid beta peptide and its fragments. Nano-electrospray ionization mass spectrometry (nESI-MS) has been utilized to examine the stabilization of bound anions on multiprotein complexes without bulk solvent. However, the effects of anions on metal ion binding interactions with amyloid beta peptide have not been explored. This study directly examined metal-peptide complexes using nESI-MS and investigated the effects of various anions on the binding ratio and stability of these complexes from ammonium salt solutions. The results indicate that different anions have distinct effects on the binding ratio and stability of various metal-peptide complexes. Of these, the bicarbonate ion exhibits the highest binding ratios for metal-peptide complexes, while binding ratios for these complexes in phosphate are comparatively low. Our results suggest that acetate, formate, bicarbonate, and phosphate have weak affinities and act as weak stabilizers of the metal-peptide complex structure in the gas phase. Intriguingly, chloride and sulfate act as stabilizers of the metal-peptide complex in the gas phase. The rank order determined from these data is substantially different from the Hofmeister salt series in solution. Although this outcome was anticipated due to the reduced influence of anions and water solvation, our findings correlate well with expected anion binding in solution and emphasize the importance of both hydration layer and anion-metal-peptide binding effects for Hofmeister-type stabilization in solution. This approach proved useful in examining the interactions between metal ions and amyloid beta peptide, which are relevant to Alzheimer's disease, using direct ESI-MS.
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Affiliation(s)
- Jingwei Zhang
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53705, United States
| | - Ashley Phetsanthad
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53705, United States
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53705, United States
- School of Pharmacy, University of Wisconsin–Madison, Madison, Wisconsin 53705, United States
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3
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Persson LJ, Sahin C, Landreh M, Marklund EG. High-Performance Molecular Dynamics Simulations for Native Mass Spectrometry of Large Protein Complexes with the Fast Multipole Method. Anal Chem 2024; 96:15023-15030. [PMID: 39231152 PMCID: PMC11411496 DOI: 10.1021/acs.analchem.4c03272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2024]
Abstract
Native mass spectrometry (MS) is widely employed to study the structures and assemblies of proteins ranging from small monomers to megadalton complexes. Molecular dynamics (MD) simulation is a useful complement as it provides the spatial detail that native MS cannot offer. However, MD simulations performed in the gas phase have suffered from rapidly increasing computational costs with the system size. The primary bottleneck is the calculation of electrostatic forces, which are effective over long distances and must be explicitly computed for each atom pair, precluding efficient use of methods traditionally used to accelerate condensed-phase simulations. As a result, MD simulations have been unable to match the capacity of MS in probing large multimeric protein complexes. Here, we apply the fast multipole method (FMM) for computing the electrostatic forces, recently implemented by Kohnke et al. (J. Chem. Theory Comput., 2020, 16, 6938-6949), showing that it significantly enhances the performance of gas-phase simulations of large proteins. We assess how to achieve adequate accuracy and optimal performance with FMM, finding that it expands the accessible size range and time scales dramatically. Additionally, we simulate a 460 kDa ferritin complex over microsecond time scales, alongside complementary ion mobility (IM)-MS experiments, uncovering conformational changes that are not apparent from the IM-MS data alone.
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Affiliation(s)
- Louise J Persson
- Department of Chemistry - BMC, Uppsala University, SE-75123 Uppsala, Sweden
| | - Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-17165 Solna, Sweden
- Department of Biology, Structural Biology and NMR Laboratory and the Linderstro̷m-Lang Centre for Protein Science, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-17165 Solna, Sweden
- Department of Cell and Molecular Biology, Uppsala University, SE-75124 Uppsala, Sweden
| | - Erik G Marklund
- Department of Chemistry - BMC, Uppsala University, SE-75123 Uppsala, Sweden
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4
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Zhao C, Slocum ST, Sherman DH, Ruotolo BT. Time-Resolved Ion Mobility-Mass Spectrometry Reveals Structural Transitions in the Disassembly of Modular Polyketide Syntheses. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:2136-2142. [PMID: 39038158 DOI: 10.1021/jasms.4c00181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
The type 1 polyketide synthase (PKS) assembly line uses its modular structure to produce polyketide natural products that form the basis of many pharmaceuticals. Currently, several cryoelectron microscopy (cryo-EM) structures of a multidomain PKS module have been constructed, but much remains to be learned. Here we utilize ion-mobility mass spectrometry (IM-MS) to record size and shape information and detect different conformational states of a 207 kDa didomain dimer comprised of ketosynthase (KS) and acyl transferase (AT), excised from full-length module. Furthermore, gas-phase stability differences between these different conformations are captured by collision induced unfolding (CIU) technology. Additionally, through tracking these forms as a function of time, we elucidate a detailed disassembly pathway for KS-AT dimers for the first time.
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Affiliation(s)
- Chunyi Zhao
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Samuel T Slocum
- Life Science Institute, Departments of Medicinal Chemistry, Chemistry and Microbiology & Immunology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - David H Sherman
- Life Science Institute, Departments of Medicinal Chemistry, Chemistry and Microbiology & Immunology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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5
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Zimnicka MM. Structural studies of supramolecular complexes and assemblies by ion mobility mass spectrometry. MASS SPECTROMETRY REVIEWS 2024; 43:526-559. [PMID: 37260128 DOI: 10.1002/mas.21851] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 04/26/2023] [Accepted: 05/10/2023] [Indexed: 06/02/2023]
Abstract
Recent advances in instrumentation and development of computational strategies for ion mobility mass spectrometry (IM-MS) studies have contributed to an extensive growth in the application of this analytical technique to comprehensive structural description of supramolecular systems. Apart from the benefits of IM-MS for interrogation of intrinsic properties of noncovalent aggregates in the experimental gas-phase environment, its merits for the description of native structural aspects, under the premises of having maintained the noncovalent interactions innate upon the ionization process, have attracted even more attention and gained increasing interest in the scientific community. Thus, various types of supramolecular complexes and assemblies relevant for biological, medical, material, and environmental sciences have been characterized so far by IM-MS supported by computational chemistry. This review covers the state-of-the-art in this field and discusses experimental methods and accompanying computational approaches for assessing the reliable three-dimensional structural elucidation of supramolecular complexes and assemblies by IM-MS.
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Affiliation(s)
- Magdalena M Zimnicka
- Mass Spectrometry Group, Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, Poland
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6
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Kenderdine T, Fabris D. The multifaceted roles of mass spectrometric analysis in nucleic acids drug discovery and development. MASS SPECTROMETRY REVIEWS 2023; 42:1332-1357. [PMID: 34939674 PMCID: PMC9218015 DOI: 10.1002/mas.21766] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/23/2021] [Accepted: 11/22/2021] [Indexed: 06/07/2023]
Abstract
The deceptively simple concepts of mass determination and fragment analysis are the basis for the application of mass spectrometry (MS) to a boundless range of analytes, including fundamental components and polymeric forms of nucleic acids (NAs). This platform affords the intrinsic ability to observe first-hand the effects of NA-active drugs on the chemical structure, composition, and conformation of their targets, which might affect their ability to interact with cognate NAs, proteins, and other biomolecules present in a natural environment. The possibility of interfacing with high-performance separation techniques represents a multiplying factor that extends these capabilities to cover complex sample mixtures obtained from organisms that were exposed to NA-active drugs. This report provides a brief overview of these capabilities in the context of the analysis of the products of NA-drug activity and NA therapeutics. The selected examples offer proof-of-principle of the applicability of this platform to all phases of the journey undertaken by any successful NA drug from laboratory to bedside, and provide the rationale for its rapid expansion outside traditional laboratory settings in support to ever growing manufacturing operations.
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Affiliation(s)
| | - Dan Fabris
- Department of Chemistry, University of Connecticut
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7
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Zercher BP, Hong S, Roush AE, Feng Y, Bush MF. Are the Gas-Phase Structures of Molecular Elephants Enduring or Ephemeral? Results from Time-Dependent, Tandem Ion Mobility. Anal Chem 2023; 95:9589-9597. [PMID: 37294019 PMCID: PMC10549206 DOI: 10.1021/acs.analchem.3c01222] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The structural stability of biomolecules in the gas phase remains an important topic in mass spectrometry applications for structural biology. Here, we evaluate the kinetic stability of native-like protein ions using time-dependent, tandem ion mobility (IM). In these tandem IM experiments, ions of interest are mobility-selected after a first dimension of IM and trapped for up to ∼14 s. Time-dependent, collision cross section distributions are then determined from separations in a second dimension of IM. In these experiments, monomeric protein ions exhibited structural changes specific to both protein and charge state, whereas large protein complexes did not undergo resolvable structural changes on the timescales of these experiments. We also performed energy-dependent experiments, i.e., collision-induced unfolding, as a comparison for time-dependent experiments to understand the extent of unfolding. Collision cross section values observed in energy-dependent experiments using high collision energies were significantly larger than those observed in time-dependent experiments, indicating that the structures observed in time-dependent experiments remain kinetically trapped and retain some memory of their solution-phase structure. Although structural evolution should be considered for highly charged, monomeric protein ions, these experiments demonstrate that higher-mass protein ions can have remarkable kinetic stability in the gas phase.
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Affiliation(s)
- Benjamin P. Zercher
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Seoyeon Hong
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Addison E. Roush
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Yuan Feng
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Matthew F. Bush
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
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8
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Christofi E, Barran P. Ion Mobility Mass Spectrometry (IM-MS) for Structural Biology: Insights Gained by Measuring Mass, Charge, and Collision Cross Section. Chem Rev 2023; 123:2902-2949. [PMID: 36827511 PMCID: PMC10037255 DOI: 10.1021/acs.chemrev.2c00600] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Indexed: 02/26/2023]
Abstract
The investigation of macromolecular biomolecules with ion mobility mass spectrometry (IM-MS) techniques has provided substantial insights into the field of structural biology over the past two decades. An IM-MS workflow applied to a given target analyte provides mass, charge, and conformation, and all three of these can be used to discern structural information. While mass and charge are determined in mass spectrometry (MS), it is the addition of ion mobility that enables the separation of isomeric and isobaric ions and the direct elucidation of conformation, which has reaped huge benefits for structural biology. In this review, where we focus on the analysis of proteins and their complexes, we outline the typical features of an IM-MS experiment from the preparation of samples, the creation of ions, and their separation in different mobility and mass spectrometers. We describe the interpretation of ion mobility data in terms of protein conformation and how the data can be compared with data from other sources with the use of computational tools. The benefit of coupling mobility analysis to activation via collisions with gas or surfaces or photons photoactivation is detailed with reference to recent examples. And finally, we focus on insights afforded by IM-MS experiments when applied to the study of conformationally dynamic and intrinsically disordered proteins.
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Affiliation(s)
- Emilia Christofi
- Michael Barber Centre for Collaborative
Mass Spectrometry, Manchester Institute of Biotechnology, University of Manchester, Princess Street, Manchester M1 7DN, United Kingdom
| | - Perdita Barran
- Michael Barber Centre for Collaborative
Mass Spectrometry, Manchester Institute of Biotechnology, University of Manchester, Princess Street, Manchester M1 7DN, United Kingdom
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9
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Abstract
Native mass spectrometry (MS) is aimed at preserving and determining the native structure, composition, and stoichiometry of biomolecules and their complexes from solution after they are transferred into the gas phase. Major improvements in native MS instrumentation and experimental methods over the past few decades have led to a concomitant increase in the complexity and heterogeneity of samples that can be analyzed, including protein-ligand complexes, protein complexes with multiple coexisting stoichiometries, and membrane protein-lipid assemblies. Heterogeneous features of these biomolecular samples can be important for understanding structure and function. However, sample heterogeneity can make assignment of ion mass, charge, composition, and structure very challenging due to the overlap of tens or even hundreds of peaks in the mass spectrum. In this review, we cover data analysis, experimental, and instrumental advances and strategies aimed at solving this problem, with an in-depth discussion of theoretical and practical aspects of the use of available deconvolution algorithms and tools. We also reflect upon current challenges and provide a view of the future of this exciting field.
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Affiliation(s)
- Amber D. Rolland
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene, OR, USA 97403-1253
| | - James S. Prell
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene, OR, USA 97403-1253
- Materials Science Institute, 1252 University of Oregon, Eugene, OR, USA 97403-1252
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10
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Snyder DT, Harvey SR, Wysocki VH. Surface-induced Dissociation Mass Spectrometry as a Structural Biology Tool. Chem Rev 2022; 122:7442-7487. [PMID: 34726898 PMCID: PMC9282826 DOI: 10.1021/acs.chemrev.1c00309] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Native mass spectrometry (nMS) is evolving into a workhorse for structural biology. The plethora of online and offline preparation, separation, and purification methods as well as numerous ionization techniques combined with powerful new hybrid ion mobility and mass spectrometry systems has illustrated the great potential of nMS for structural biology. Fundamental to the progression of nMS has been the development of novel activation methods for dissociating proteins and protein complexes to deduce primary, secondary, tertiary, and quaternary structure through the combined use of multiple MS/MS technologies. This review highlights the key features and advantages of surface collisions (surface-induced dissociation, SID) for probing the connectivity of subunits within protein and nucleoprotein complexes and, in particular, for solving protein structure in conjunction with complementary techniques such as cryo-EM and computational modeling. Several case studies highlight the significant role SID, and more generally nMS, will play in structural elucidation of biological assemblies in the future as the technology becomes more widely adopted. Cases are presented where SID agrees with solved crystal or cryoEM structures or provides connectivity maps that are otherwise inaccessible by "gold standard" structural biology techniques.
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Affiliation(s)
- Dalton T. Snyder
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
| | - Sophie R. Harvey
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Vicki H. Wysocki
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
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11
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Rogawski R, Sharon M. Characterizing Endogenous Protein Complexes with Biological Mass Spectrometry. Chem Rev 2022; 122:7386-7414. [PMID: 34406752 PMCID: PMC9052418 DOI: 10.1021/acs.chemrev.1c00217] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Indexed: 01/11/2023]
Abstract
Biological mass spectrometry (MS) encompasses a range of methods for characterizing proteins and other biomolecules. MS is uniquely powerful for the structural analysis of endogenous protein complexes, which are often heterogeneous, poorly abundant, and refractive to characterization by other methods. Here, we focus on how biological MS can contribute to the study of endogenous protein complexes, which we define as complexes expressed in the physiological host and purified intact, as opposed to reconstituted complexes assembled from heterologously expressed components. Biological MS can yield information on complex stoichiometry, heterogeneity, topology, stability, activity, modes of regulation, and even structural dynamics. We begin with a review of methods for isolating endogenous complexes. We then describe the various biological MS approaches, focusing on the type of information that each method yields. We end with future directions and challenges for these MS-based methods.
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Affiliation(s)
- Rivkah Rogawski
- 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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12
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Al-Jabiry A, Palmer M, Langridge J, Bellamy-Carter J, Robinson D, Oldham NJ. Combined Chemical Modification and Collision Induced Unfolding Using Native Ion Mobility-Mass Spectrometry Provides Insights into Protein Gas-Phase Structure. Chemistry 2021; 27:13783-13792. [PMID: 34289194 DOI: 10.1002/chem.202101857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Indexed: 11/10/2022]
Abstract
Native mass spectrometry is now an important tool in structural biology. Thus, the nature of higher protein structure in the vacuum of the mass spectrometer is an area of significant interest. One of the major goals in the study of gas-phase protein structure is to elucidate the stabilising role of interactions at the level of individual amino acid residues. A strategy combining protein chemical modification together with collision induced unfolding (CIU) was developed and employed to probe the structure of compact protein ions produced by native electrospray ionisation. Tractable chemical modification was used to alter the properties of amino acid residues, and ion mobility-mass spectrometry (IM-MS) utilised to monitor the extent of unfolding as a function of modification. From these data the importance of specific intramolecular interactions for the stability of compact gas-phase protein structure can be inferred. Using this approach, and aided by molecular dynamics simulations, an important stabilising interaction between K6 and H68 in the protein ubiquitin was identified, as was a contact between the N-terminus and E22 in a ubiquitin binding protein UBA2.
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Affiliation(s)
- Asia Al-Jabiry
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Martin Palmer
- Waters Corporation, Stamford Avenue Altrincham Road, Wilmslow, Cheshire, SK9 4AX, UK
| | - James Langridge
- Waters Corporation, Stamford Avenue Altrincham Road, Wilmslow, Cheshire, SK9 4AX, UK
| | | | - David Robinson
- School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham, NG11 8NS, UK
| | - Neil J Oldham
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
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13
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Skeene K, Khatri K, Soloviev Z, Lapthorn C. Current status and future prospects for ion-mobility mass spectrometry in the biopharmaceutical industry. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140697. [PMID: 34246790 DOI: 10.1016/j.bbapap.2021.140697] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/11/2021] [Accepted: 07/06/2021] [Indexed: 12/12/2022]
Abstract
Detailed characterization of protein reagents and biopharmaceuticals is key in defining successful drug discovery campaigns, aimed at bringing molecules through different discovery stages up to development and commercialization. There are many challenges in this process, with complex and detailed analyses playing paramount roles in modern industry. Mass spectrometry (MS) has become an essential tool for characterization of proteins ever since the onset of soft ionization techniques and has taken the lead in quality assessment of biopharmaceutical molecules, and protein reagents, used in the drug discovery pipeline. MS use spans from identification of correct sequences, to intact molecule analyses, protein complexes and more recently epitope and paratope identification. MS toolkits could be incredibly diverse and with ever evolving instrumentation, increasingly novel MS-based techniques are becoming indispensable tools in the biopharmaceutical industry. Here we discuss application of Ion Mobility MS (IMMS) in an industrial setting, and what the current applications and outlook are for making IMMS more mainstream.
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Affiliation(s)
- Kirsty Skeene
- Biopharm Process Research, Medicinal Science and Technology, GlaxoSmithKline, Stevenage SG1 2NY, UK.
| | - Kshitij Khatri
- Structure and Function Characterization, CMC-Analytical, GlaxoSmithKline, Collegeville, PA 19406, USA.
| | - Zoja Soloviev
- Protein, Cellular and Structural Sciences, Medicinal Science and Technology, GlaxoSmithKline, Stevenage SG1 2NY, UK.
| | - Cris Lapthorn
- Structure and Function Characterization, CMC-Analytical, GlaxoSmithKline, Stevenage SG1 2NY, UK.
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14
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Lau AM, Politis A. Integrative Mass Spectrometry-Based Approaches for Modeling Macromolecular Assemblies. Methods Mol Biol 2021; 2247:221-241. [PMID: 33301120 DOI: 10.1007/978-1-0716-1126-5_12] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Mass spectrometry (MS)-based strategies have emerged as key elements for structural modeling of proteins and their assemblies. In particular, merging together complementary MS tools, through the so-called hybrid approaches, has enabled structural characterization of proteins in their near-native states. Here, we describe how different MS techniques, such as native MS, chemical cross-linking MS, and ion mobility MS, are brought together using sophisticated computational algorithms and modeling restraints. We demonstrate the applicability of the strategy by building accurate models of multimeric protein assemblies. These strategies can practically be applied to any protein complex of interest and be readily integrated with other structural approaches such as electron density maps from cryo-electron microscopy.
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Affiliation(s)
- Andy M Lau
- Department of Chemistry, King's College London, London, UK
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15
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Landreh M, Sahin C, Gault J, Sadeghi S, Drum CL, Uzdavinys P, Drew D, Allison TM, Degiacomi MT, Marklund EG. Predicting the Shapes of Protein Complexes through Collision Cross Section Measurements and Database Searches. Anal Chem 2020; 92:12297-12303. [PMID: 32660238 DOI: 10.1021/acs.analchem.0c01940] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In structural biology, collision cross sections (CCSs) from ion mobility mass spectrometry (IM-MS) measurements are routinely compared to computationally or experimentally derived protein structures. Here, we investigate whether CCS data can inform about the shape of a protein in the absence of specific reference structures. Analysis of the proteins in the CCS database shows that protein complexes with low apparent densities are structurally more diverse than those with a high apparent density. Although assigning protein shapes purely on CCS data is not possible, we find that we can distinguish oblate- and prolate-shaped protein complexes by using the CCS, molecular weight, and oligomeric states to mine the Protein Data Bank (PDB) for potentially similar protein structures. Furthermore, comparing the CCS of a ferritin cage to the solution structures in the PDB reveals significant deviations caused by structural collapse in the gas phase. We then apply the strategy to an integral membrane protein by comparing the shapes of a prokaryotic and a eukaryotic sodium/proton antiporter homologue. We conclude that mining the PDB with IM-MS data is a time-effective way to derive low-resolution structural models.
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Affiliation(s)
- Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solnavägen 9, 171 65, Stockholm, Sweden
| | - Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solnavägen 9, 171 65, Stockholm, Sweden.,Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Joseph Gault
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Samira Sadeghi
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 10 Medical Dr, Singapore 119228, Singapore
| | - Chester L Drum
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 10 Medical Dr, Singapore 119228, Singapore
| | - Povilas Uzdavinys
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm 114 19, Sweden
| | - David Drew
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm 114 19, Sweden
| | - Timothy M Allison
- Biomolecular Interaction Centre and School of Physical and Chemical Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - Matteo T Degiacomi
- Department of Physics, Durham University, South Road, Durham DH1 3LE, United Kingdom
| | - Erik G Marklund
- Department of Chemistry - BMC, Uppsala University, Box 576, Uppsala 751 23, Sweden
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16
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Allison TM, Barran P, Cianférani S, Degiacomi MT, Gabelica V, Grandori R, Marklund EG, Menneteau T, Migas LG, Politis A, Sharon M, Sobott F, Thalassinos K, Benesch JLP. Computational Strategies and Challenges for Using Native Ion Mobility Mass Spectrometry in Biophysics and Structural Biology. Anal Chem 2020; 92:10872-10880. [DOI: 10.1021/acs.analchem.9b05791] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Timothy M. Allison
- School of Physical and Chemical Sciences, Biomolecular Interaction Centre, University of Canterbury, Christchurch 8140, New Zealand
| | - Perdita Barran
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, Manchester M1 7DN, United Kingdom
| | - Sarah Cianférani
- Laboratoire de Spectrométrie de Masse BioOrganique (LSMBO), Université de Strasbourg, CNRS, IPHC UMR 7178, 67000 Strasbourg, France
| | - Matteo T. Degiacomi
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Valérie Gabelica
- University of Bordeaux, INSERM and CNRS, ARNA Laboratory, IECB site, 2 Rue Robert Escarpit, 33600 Pessac, France
| | - Rita Grandori
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126, Milan, Italy
| | - Erik G. Marklund
- Department of Chemistry - BMC, Uppsala University, Box 576, 75123, Uppsala, Sweden
| | - Thomas Menneteau
- Division of Biosciences, Institute of Structural and Molecular Biology, University College of London, Gower Street, London WC1E 6BT, United Kingdom
| | - Lukasz G. Migas
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, Manchester M1 7DN, United Kingdom
| | - Argyris Politis
- Department of Chemistry, King’s College London, 7 Trinity Street, London SE1 1DB, United Kingdom
| | - Michal Sharon
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Frank Sobott
- Biomolecular & Analytical Mass Spectrometry, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Konstantinos Thalassinos
- Department of Chemistry, King’s College London, 7 Trinity Street, London SE1 1DB, United Kingdom
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, Malet Street, London WC1E 7HX, United Kingdom
| | - Justin L. P. Benesch
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, South Parks Road, Oxford OX1 3TA, United Kingdom
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17
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Dixit SM, Richardson K, Langridge D, Giles K, Ruotolo BT. A Novel Ion Pseudo-trapping Phenomenon within Traveling Wave Ion Guides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:880-887. [PMID: 32134265 DOI: 10.1021/jasms.9b00095] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The widespread use of traveling wave ion mobility (TWIM) technology in fields such as omics and structural biology motivates efforts to deepen our understanding of ion transport within such devices. Here, we describe a new advancement in TWIM theory, where pseudo-trapping within TW ion guides is characterized in detail. During pseudo-trapping, ions with different mobilities can travel with the same mean velocity, leaving others within the same TWIM experiment to separate as normal. Furthermore, pseudo-trapping limits typical band broadening experienced by ions during TWIM, manifesting as peaks with apparently improved IM resolving power, but all ions that undergo pseudo trapping are unable to separate by IM. SIMION simulations show that ions become locked into a repeated pattern of motion with respect to the TW reference frame during pseudo-trapping. We developed a simplified model capable of reproducing TW pseudo-trapping and reproducing trends observed in experimental data. Our model and simulations suggest that pseudo-trapping occurs only during experiments performed under static TWIM conditions, to an extent that depends on the detailed shape of the traveling wave. We show that pseudo-trapping alters the ion transit times and can adversely affect calibrated CCS measurements. Finally, we provide recommendations for avoiding unintentional pseudo-trapping in TWIM in order to obtain optimal separations and CCS determinations.
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Affiliation(s)
- Sugyan M Dixit
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Keith Richardson
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow SK9 4AX, U.K
| | - David Langridge
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow SK9 4AX, U.K
| | - Kevin Giles
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow SK9 4AX, U.K
| | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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18
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Marcinko TM, Liang C, Savinov S, Chen J, Vachet RW. Structural Heterogeneity in the Preamyloid Oligomers of β-2-Microglobulin. J Mol Biol 2019; 432:396-409. [PMID: 31711963 DOI: 10.1016/j.jmb.2019.10.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/25/2019] [Accepted: 10/30/2019] [Indexed: 11/29/2022]
Abstract
In dialysis patients, the protein β2-microglobulin (β2m) forms amyloid fibrils in a condition known as dialysis-related amyloidosis. To understand the early stages of the amyloid assembly process, we have used native electrospray ionization (ESI) together with ion mobility mass spectrometry (IM-MS) to study soluble preamyloid oligomers. ESI-IM-MS reveals the presence of multiple conformers for the dimer, tetramer, and hexamer that precede the Cu(II)-induced amyloid assembly process, results which are distinct from β2m oligomers formed at low pH. Experimental and computational results indicate that the predominant dimer is a Cu(II)-bound structure with an antiparallel side-by-side configuration. In contrast, tetramers exist in solution in both Cu(II)-bound and Cu(II)-free forms. Selective depletion of Cu(II)-bound species results in two primary conformers-one that is compact and another that is more expanded. Molecular modeling and molecular dynamics simulations identify models for these two tetrameric conformers with unique interactions and interfaces that enthalpically compensate for the loss of Cu(II). Unlike with other amyloid systems in which conformational heterogeneity is often associated with different amyloid morphologies or off-pathway events, conformational heterogeneity in the tetramer seems to be a necessary aspect of Cu(II)-induced amyloid formation by β2m. Moreover, the Cu(II)-free models represent a new advance in our understanding of Cu(II) release in Cu(II)-induced amyloid formation, laying a foundation for further mechanistic studies as well as development of new inhibition strategies.
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Affiliation(s)
- Tyler M Marcinko
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States
| | - Chungwen Liang
- Computational and Modeling Core Facility, Institute for Applied Life Sciences, Amherst, MA 01003, United States
| | - Sergey Savinov
- Computational and Modeling Core Facility, Institute for Applied Life Sciences, Amherst, MA 01003, United States; Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, United States
| | - Jianhen Chen
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States; Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, United States
| | - Richard W Vachet
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States.
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19
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Lee JH, Pollert K, Konermann L. Testing the Robustness of Solution Force Fields for MD Simulations on Gaseous Protein Ions. J Phys Chem B 2019; 123:6705-6715. [DOI: 10.1021/acs.jpcb.9b04014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Justin H. Lee
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Katja Pollert
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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20
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Pukala T. Importance of collision cross section measurements by ion mobility mass spectrometry in structural biology. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33 Suppl 3:72-82. [PMID: 30265417 DOI: 10.1002/rcm.8294] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 09/17/2018] [Accepted: 09/19/2018] [Indexed: 06/08/2023]
Abstract
The field of ion mobility mass spectrometry (IM-MS) has developed rapidly in recent decades, with new fundamental advances underpinning innovative applications. This has been particularly noticeable in the field of biomacromolecular structure determination and structural biology, with pioneering studies revealing new structural insight for complex protein assemblies which control biological function. This perspective offers a review of recent developments in IM-MS which have enabled expanding applications in protein structural biology, principally focusing on the quantitative measurement of collision cross sections and their interpretation to describe higher order protein structures.
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Affiliation(s)
- Tara Pukala
- Discipline of Chemistry, University of Adelaide, North Terrace, Adelaide, South Australia, 5005
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21
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Gabelica V, Shvartsburg AA, Afonso C, Barran P, Benesch JL, Bleiholder C, Bowers MT, Bilbao A, Bush MF, Campbell JL, Campuzano ID, Causon T, Clowers BH, Creaser CS, De Pauw E, Far J, Fernandez‐Lima F, Fjeldsted JC, Giles K, Groessl M, Hogan CJ, Hann S, Kim HI, Kurulugama RT, May JC, McLean JA, Pagel K, Richardson K, Ridgeway ME, Rosu F, Sobott F, Thalassinos K, Valentine SJ, Wyttenbach T. Recommendations for reporting ion mobility Mass Spectrometry measurements. MASS SPECTROMETRY REVIEWS 2019; 38:291-320. [PMID: 30707468 PMCID: PMC6618043 DOI: 10.1002/mas.21585] [Citation(s) in RCA: 304] [Impact Index Per Article: 60.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/01/2018] [Accepted: 11/02/2018] [Indexed: 05/02/2023]
Abstract
Here we present a guide to ion mobility mass spectrometry experiments, which covers both linear and nonlinear methods: what is measured, how the measurements are done, and how to report the results, including the uncertainties of mobility and collision cross section values. The guide aims to clarify some possibly confusing concepts, and the reporting recommendations should help researchers, authors and reviewers to contribute comprehensive reports, so that the ion mobility data can be reused more confidently. Starting from the concept of the definition of the measurand, we emphasize that (i) mobility values (K0 ) depend intrinsically on ion structure, the nature of the bath gas, temperature, and E/N; (ii) ion mobility does not measure molecular surfaces directly, but collision cross section (CCS) values are derived from mobility values using a physical model; (iii) methods relying on calibration are empirical (and thus may provide method-dependent results) only if the gas nature, temperature or E/N cannot match those of the primary method. Our analysis highlights the urgency of a community effort toward establishing primary standards and reference materials for ion mobility, and provides recommendations to do so. © 2019 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Valérie Gabelica
- University of Bordeaux, INSERM and CNRS, ARNA Laboratory, IECB site2 rue Robert Escarpit, 33600PessacFrance
| | | | | | - Perdita Barran
- Michael Barber Centre for Collaborative Mass SpectrometryManchester Institute for Biotechnology, University of ManchesterManchesterUK
| | - Justin L.P. Benesch
- Department of Chemistry, Chemistry Research LaboratoryUniversity of Oxford, Mansfield Road, OX1 3TAOxfordUK
| | - Christian Bleiholder
- Department of Chemistry and BiochemistryFlorida State UniversityTallahasseeFlorida32311
| | | | - Aivett Bilbao
- Biological Sciences DivisionPacific Northwest National LaboratoryRichlandWashington
| | - Matthew F. Bush
- Department of ChemistryUniversity of WashingtonSeattleWashington
| | | | | | - Tim Causon
- University of Natural Resources and Life Sciences (BOKU)Department of Chemistry, Division of Analytical ChemistryViennaAustria
| | - Brian H. Clowers
- Department of ChemistryWashington State UniversityPullmanWashington
| | - Colin S. Creaser
- Centre for Analytical ScienceDepartment of Chemistry, Loughborough UniversityLoughboroughUK
| | - Edwin De Pauw
- Laboratoire de spectrométrie de masse (L.S.M.) − Molecular SystemsUniversité de LiègeLiègeBelgium
| | - Johann Far
- Laboratoire de spectrométrie de masse (L.S.M.) − Molecular SystemsUniversité de LiègeLiègeBelgium
| | | | | | | | - Michael Groessl
- Department of Nephrology and Hypertension and Department of BioMedical ResearchInselspital, Bern University Hospital, University of Bern, Switzerland and TofwerkThunSwitzerland
| | | | - Stephan Hann
- University of Natural Resources and Life Sciences (BOKU)Department of Chemistry, Division of Analytical ChemistryViennaAustria
| | - Hugh I. Kim
- Department of ChemistryKorea UniversitySeoulKorea
| | | | - Jody C. May
- Department of ChemistryCenter for Innovative Technology, Vanderbilt UniversityNashvilleTennessee
| | - John A. McLean
- Department of ChemistryCenter for Innovative Technology, Vanderbilt UniversityNashvilleTennessee
| | - Kevin Pagel
- Freie Universitaet BerlinInstitute for Chemistry and BiochemistryBerlinGermany
| | | | | | - Frédéric Rosu
- CNRS, INSERM and University of BordeauxInstitut Européen de Chimie et BiologiePessacFrance
| | - Frank Sobott
- Antwerp UniversityBiomolecular & Analytical Mass SpectrometryAntwerpBelgium
- Astbury Centre for Structural Molecular BiologyUniversity of LeedsLeedsUK
- School of Molecular and Cellular BiologyUniversity of LeedsLeedsUK
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of BiosciencesUniversity College LondonLondonWC1E 6BTUK
- United Kingdom and Institute of Structural and Molecular BiologyDepartment of Biological Sciences, Birkbeck College, University of LondonLondonWC1E 7HXUK
| | - Stephen J. Valentine
- C. Eugene Bennett Department of ChemistryWest Virginia UniversityMorgantownWest Virginia
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22
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Stiving AQ, VanAernum ZL, Busch F, Harvey SR, Sarni SH, Wysocki VH. Surface-Induced Dissociation: An Effective Method for Characterization of Protein Quaternary Structure. Anal Chem 2019; 91:190-209. [PMID: 30412666 PMCID: PMC6571034 DOI: 10.1021/acs.analchem.8b05071] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Alyssa Q. Stiving
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
| | - Zachary L. VanAernum
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
| | - Florian Busch
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Campus Chemical Instrument Center, The Ohio State University, Columbus, OH 43210
| | - Sophie R. Harvey
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Campus Chemical Instrument Center, The Ohio State University, Columbus, OH 43210
| | - Samantha H. Sarni
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210
- The Center for RNA Biology, The Ohio State University, Columbus, OH 43210
| | - Vicki H. Wysocki
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Campus Chemical Instrument Center, The Ohio State University, Columbus, OH 43210
- The Center for RNA Biology, The Ohio State University, Columbus, OH 43210
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23
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Ion Mobility in Structural Biology. ADVANCES IN ION MOBILITY-MASS SPECTROMETRY: FUNDAMENTALS, INSTRUMENTATION AND APPLICATIONS 2019. [DOI: 10.1016/bs.coac.2018.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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24
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Kulesza A, Marklund EG, MacAleese L, Chirot F, Dugourd P. Bringing Molecular Dynamics and Ion-Mobility Spectrometry Closer Together: Shape Correlations, Structure-Based Predictors, and Dissociation. J Phys Chem B 2018; 122:8317-8329. [DOI: 10.1021/acs.jpcb.8b03825] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexander Kulesza
- Université de Lyon, F-69622, Lyon, France
- CNRS et
Université
Lyon 1, UMR5306, Institut Lumière Matière, France
| | - Erik G. Marklund
- Department of Chemistry − BMC, Uppsala University, Box 576, SE-751 23, Uppsala, Sweden
| | - Luke MacAleese
- Université de Lyon, F-69622, Lyon, France
- CNRS et
Université
Lyon 1, UMR5306, Institut Lumière Matière, France
| | - Fabien Chirot
- Université
Lyon, Université Claude Bernard Lyon 1, Ens de Lyon, CNRS,
Institut des Sciences Analytiques UMR 5280, F-69100, Villeurbanne, France
| | - Philippe Dugourd
- Université de Lyon, F-69622, Lyon, France
- CNRS et
Université
Lyon 1, UMR5306, Institut Lumière Matière, France
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25
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Bullock JMA, Sen N, Thalassinos K, Topf M. Modeling Protein Complexes Using Restraints from Crosslinking Mass Spectrometry. Structure 2018; 26:1015-1024.e2. [PMID: 29804821 PMCID: PMC6039719 DOI: 10.1016/j.str.2018.04.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 03/05/2018] [Accepted: 04/25/2018] [Indexed: 11/16/2022]
Abstract
Modeling macromolecular assemblies with restraints from crosslinking mass spectrometry (XL-MS) tends to focus solely on distance violation. Recently, we identified three different modeling features inherent in crosslink data: (1) expected distance between crosslinked residues; (2) violation of the crosslinker's maximum bound; and (3) solvent accessibility of crosslinked residues. Here, we implement these features in a scoring function. cMNXL, and demonstrate that it outperforms the commonlyused crosslink distance violation. We compare the different methods of calculating the distance between crosslinked residues, which shows no significant change in performance when using Euclidean distance compared with the solvent-accessible surface distance. Finally, we create a combined score that incorporates information from 3D electron microscopy maps as well as crosslinking. This achieves, on average, better results than either information type alone and demonstrates the potential of integrative modeling with XL-MS and low-resolution cryoelectron microscopy.
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Affiliation(s)
- Joshua Matthew Allen Bullock
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK
| | - Neeladri Sen
- Indian Institute of Science Education and Research Pune, Pashan, Pune 411 008, India
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK; Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, UK
| | - Maya Topf
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK.
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26
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Structural Lipids Enable the Formation of Functional Oligomers of the Eukaryotic Purine Symporter UapA. Cell Chem Biol 2018; 25:840-848.e4. [PMID: 29681524 PMCID: PMC6058078 DOI: 10.1016/j.chembiol.2018.03.011] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 02/27/2018] [Accepted: 03/22/2018] [Indexed: 11/25/2022]
Abstract
The role of membrane lipids in modulating eukaryotic transporter assembly and function remains unclear. We investigated the effect of membrane lipids in the structure and transport activity of the purine transporter UapA from Aspergillus nidulans. We found that UapA exists mainly as a dimer and that two lipid molecules bind per UapA dimer. We identified three phospholipid classes that co-purified with UapA: phosphatidylcholine, phosphatidylethanolamine (PE), and phosphatidylinositol (PI). UapA delipidation caused dissociation of the dimer into monomers. Subsequent addition of PI or PE rescued the UapA dimer and allowed recovery of bound lipids, suggesting a central role of these lipids in stabilizing the dimer. Molecular dynamics simulations predicted a lipid binding site near the UapA dimer interface. Mutational analyses established that lipid binding at this site is essential for formation of functional UapA dimers. We propose that structural lipids have a central role in the formation of functional, dimeric UapA. Mass spectrometry reveals specific lipid binding to the eukaryotic transporter UapA Interfacial lipids stabilize the functional UapA dimer MD simulations reveal the lipid binding sites Mutagenesis of a lipid binding site disrupts UapA dimerization and function in vivo
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27
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A Structural Model of the Urease Activation Complex Derived from Ion Mobility-Mass Spectrometry and Integrative Modeling. Structure 2018; 26:599-606.e3. [PMID: 29576318 DOI: 10.1016/j.str.2018.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 12/16/2017] [Accepted: 02/28/2018] [Indexed: 01/14/2023]
Abstract
The synthesis of active Klebsiella aerogenes urease via an 18-subunit enzyme apoprotein-accessory protein pre-activation complex has been well studied biochemically, but thus far this complex has remained refractory to direct structural characterization. Using ion mobility-mass spectrometry, we characterized several protein complexes between the core urease apoprotein and its accessory proteins, including the 610-kDa (UreABC)3(UreDFG)3 complex. Using our recently developed computational modeling workflow, we generated ensembles of putative (UreABC)3(UreDFG)3 species consistent with experimental restraints and characterized the structural ambiguity present in these models. By integrating structural information from previous studies, we increased the resolution of the ion mobility-mass spectrometry-derived models substantially, and we observe a discrete population of structures consistent with all of the available data for this complex.
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28
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Politis A, Schmidt C. Structural characterisation of medically relevant protein assemblies by integrating mass spectrometry with computational modelling. J Proteomics 2018; 175:34-41. [DOI: 10.1016/j.jprot.2017.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 04/13/2017] [Accepted: 04/18/2017] [Indexed: 01/14/2023]
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29
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Eyers CE, Vonderach M, Ferries S, Jeacock K, Eyers PA. Understanding protein–drug interactions using ion mobility–mass spectrometry. Curr Opin Chem Biol 2018; 42:167-176. [DOI: 10.1016/j.cbpa.2017.12.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/08/2017] [Accepted: 12/22/2017] [Indexed: 01/23/2023]
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30
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D'Atri V, Causon T, Hernandez-Alba O, Mutabazi A, Veuthey JL, Cianferani S, Guillarme D. Adding a new separation dimension to MS and LC-MS: What is the utility of ion mobility spectrometry? J Sep Sci 2017; 41:20-67. [PMID: 29024509 DOI: 10.1002/jssc.201700919] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 12/12/2022]
Abstract
Ion mobility spectrometry is an analytical technique known for more than 100 years, which entails separating ions in the gas phase based on their size, shape, and charge. While ion mobility spectrometry alone can be useful for some applications (mostly security analysis for detecting certain classes of narcotics and explosives), it becomes even more powerful in combination with mass spectrometry and high-performance liquid chromatography. Indeed, the limited resolving power of ion mobility spectrometry alone can be tackled when combining this analytical strategy with mass spectrometry or liquid chromatography with mass spectrometry. Over the last few years, the hyphenation of ion mobility spectrometry to mass spectrometry or liquid chromatography with mass spectrometry has attracted more and more interest, with significant progresses in both technical advances and pioneering applications. This review describes the theoretical background, available technologies, and future capabilities of these techniques. It also highlights a wide range of applications, from small molecules (natural products, metabolites, glycans, lipids) to large biomolecules (proteins, protein complexes, biopharmaceuticals, oligonucleotides).
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Affiliation(s)
- Valentina D'Atri
- School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Tim Causon
- Division of Analytical Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences (BOKU Vienna), Vienna, Austria
| | - Oscar Hernandez-Alba
- BioOrganic Mass Spectrometry Laboratory (LSMBO), IPHC, Université de Strasbourg, CNRS, Strasbourg, France
| | - Aline Mutabazi
- School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Jean-Luc Veuthey
- School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Sarah Cianferani
- BioOrganic Mass Spectrometry Laboratory (LSMBO), IPHC, Université de Strasbourg, CNRS, Strasbourg, France
| | - Davy Guillarme
- School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
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31
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Eschweiler JD, Frank AT, Ruotolo BT. Coming to Grips with Ambiguity: Ion Mobility-Mass Spectrometry for Protein Quaternary Structure Assignment. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1991-2000. [PMID: 28752478 PMCID: PMC5693686 DOI: 10.1007/s13361-017-1757-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 07/04/2017] [Accepted: 07/05/2017] [Indexed: 05/21/2023]
Abstract
Multiprotein complexes are central to our understanding of cellular biology, as they play critical roles in nearly every biological process. Despite many impressive advances associated with structural characterization techniques, large and highly-dynamic protein complexes are too often refractory to analysis by conventional, high-resolution approaches. To fill this gap, ion mobility-mass spectrometry (IM-MS) methods have emerged as a promising approach for characterizing the structures of challenging assemblies due in large part to the ability of these methods to characterize the composition, connectivity, and topology of large, labile complexes. In this Critical Insight, we present a series of bioinformatics studies aimed at assessing the information content of IM-MS datasets for building models of multiprotein structure. Our computational data highlights the limits of current coarse-graining approaches, and compelled us to develop an improved workflow for multiprotein topology modeling, which we benchmark against a subset of the multiprotein complexes within the PDB. This improved workflow has allowed us to ascertain both the minimal experimental restraint sets required for generation of high-confidence multiprotein topologies, and quantify the ambiguity in models where insufficient IM-MS information is available. We conclude by projecting the future of IM-MS in the context of protein quaternary structure assignment, where we predict that a more complete knowledge of the ultimate information content and ambiguity within such models will undoubtedly lead to applications for a broader array of challenging biomolecular assemblies. Graphical Abstract ᅟ.
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Affiliation(s)
| | - Aaron T Frank
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA.
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32
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Laszlo KJ, Bush MF. Effects of Charge State, Charge Distribution, and Structure on the Ion Mobility of Protein Ions in Helium Gas: Results from Trajectory Method Calculations. J Phys Chem A 2017; 121:7768-7777. [PMID: 28910102 DOI: 10.1021/acs.jpca.7b08154] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Collision cross section (Ω) values of gas-phase ions of proteins and protein complexes are used to probe the structures of the corresponding species in solution. Ions of many proteins exhibit increasing Ω-values with increasing charge state but most Ω-values calculated for protein ions have used simple collision models that do not explicitly account for charge. Here we use a combination of ion mobility mass spectrometry experiments with helium gas and trajectory method calculations to characterize the extents to which increases in experimental Ω-values with increasing charge state may be attributed to increased momentum transfer concomitant with enhanced long-range interactions between the protein ion and helium atoms. Ubiquitin and C-to-N terminally linked diubiquitin ions generated from different solution conditions exhibit more than a 2-fold increase in Ω with increasing charge state. For native and energy-relaxed models of the proteins and most methods for distributing charge, Ω-values calculated using the trajectory method increase by less than 1% over the range of charge states observed from typical solution conditions used for native mass spectrometry. However, the calculated Ω-values increase by 10% to 15% over the full range of charge states observed from all solution conditions. Therefore, contributions from enhanced ion-induced dipole interactions with increasing charge state are significant but without additional structural changes can account for only a fraction of the increase in Ω observed experimentally. On the basis of these results, we suggest guidelines for calculating Ω-values in the context of applications in biophysics and structural biology.
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Affiliation(s)
- Kenneth J Laszlo
- University of Washington , Department of Chemistry, Box 351700, Seattle, Washington 98195-1700, United States
| | - Matthew F Bush
- University of Washington , Department of Chemistry, Box 351700, Seattle, Washington 98195-1700, United States
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33
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Schmidt C, Macpherson JA, Lau AM, Tan KW, Fraternali F, Politis A. Surface Accessibility and Dynamics of Macromolecular Assemblies Probed by Covalent Labeling Mass Spectrometry and Integrative Modeling. Anal Chem 2017; 89:1459-1468. [PMID: 28208298 PMCID: PMC5299547 DOI: 10.1021/acs.analchem.6b02875] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 01/04/2017] [Indexed: 12/22/2022]
Abstract
Mass spectrometry (MS) has become an indispensable tool for investigating the architectures and dynamics of macromolecular assemblies. Here we show that covalent labeling of solvent accessible residues followed by their MS-based identification yields modeling restraints that allow mapping the location and orientation of subunits within protein assemblies. Together with complementary restraints derived from cross-linking and native MS, we built native-like models of four heterocomplexes with known subunit structures and compared them with available X-ray crystal structures. The results demonstrated that covalent labeling followed by MS markedly increased the predictive power of the integrative modeling strategy enabling more accurate protein assembly models. We applied this strategy to the F-type ATP synthase from spinach chloroplasts (cATPase) providing a structural basis for its function as a nanomotor. By subjecting the models generated by our restraint-based strategy to molecular dynamics (MD) simulations, we revealed the conformational states of the peripheral stalk and assigned flexible regions in the enzyme. Our strategy can readily incorporate complementary chemical labeling strategies and we anticipate that it will be applicable to many other systems providing new insights into the structure and function of protein complexes.
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Affiliation(s)
- Carla Schmidt
- Interdisciplinary
Research Center HALOmem, Martin Luther University
Halle-Wittenberg, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Jamie A. Macpherson
- Division
of Cell & Molecular Biophysics, King’s
College London, New Hunt’s
House, SE1 1UL, London, United Kingdom
| | - Andy M. Lau
- Department
of Chemistry, King’s College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
| | - Ken Wei Tan
- Department
of Chemistry, King’s College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
| | - Franca Fraternali
- Division
of Cell & Molecular Biophysics, King’s
College London, New Hunt’s
House, SE1 1UL, London, United Kingdom
| | - Argyris Politis
- Department
of Chemistry, King’s College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
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34
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Zhao Y, Singh A, Xu Y, Zong C, Zhang F, Boons GJ, Liu J, Linhardt RJ, Woods RJ, Amster IJ. Gas-Phase Analysis of the Complex of Fibroblast GrowthFactor 1 with Heparan Sulfate: A Traveling Wave Ion Mobility Spectrometry (TWIMS) and Molecular Modeling Study. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:96-109. [PMID: 27663556 PMCID: PMC5177502 DOI: 10.1007/s13361-016-1496-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 08/26/2016] [Accepted: 08/30/2016] [Indexed: 05/10/2023]
Abstract
Fibroblast growth factors (FGFs) regulate several cellular developmental processes by interacting with cell surface heparan proteoglycans and transmembrane cell surface receptors (FGFR). The interaction of FGF with heparan sulfate (HS) is known to induce protein oligomerization, increase the affinity of FGF towards its receptor FGFR, promoting the formation of the HS-FGF-FGFR signaling complex. Although the role of HS in the signaling pathways is well recognized, the details of FGF oligomerization and formation of the ternary signaling complex are still not clear, with several conflicting models proposed in literature. Here, we examine the effect of size and sulfation pattern of HS upon FGF1 oligomerization, binding stoichiometry and conformational stability, through a combination of ion mobility (IM) and theoretical modeling approaches. Ion mobility-mass spectrometry (IMMS) of FGF1 in the presence of several HS fragments ranging from tetrasaccharide (dp4) to dodecasaccharide (dp12) in length was performed. A comparison of the binding stoichiometry of variably sulfated dp4 HS to FGF1 confirmed the significance of the previously known high-affinity binding motif in FGF1 dimerization, and demonstrated that certain tetrasaccharide-length fragments are also capable of inducing dimerization of FGF1. The degree of oligomerization was found to increase in the presence of dp12 HS, and a general lack of specificity for longer HS was observed. Additionally, collision cross-sections (CCSs) of several FGF1-HS complexes were calculated, and were found to be in close agreement with experimental results. Based on the (CCSs) a number of plausible binding modes of 2:1 and 3:1 FGF1-HS are proposed. Graphical Abstract ᅟ.
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Affiliation(s)
- Yuejie Zhao
- Department of Chemistry, University of Georgia, Athens, GA, 30602, USA
| | - Arunima Singh
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | - Yongmei Xu
- Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC, USA
| | - Chengli Zong
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | - Fuming Zhang
- Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | - Jian Liu
- Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, University of North Carolina, Chapel Hill, NC, USA
| | - Robert J Linhardt
- Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Robert J Woods
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | - I Jonathan Amster
- Department of Chemistry, University of Georgia, Athens, GA, 30602, USA.
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35
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Benigni P, Marin R, Molano-Arevalo JC, Garabedian A, Wolff JJ, Ridgeway ME, Park MA, Fernandez-Lima F. Towards the Analysis of High Molecular Weight Proteins and Protein complexes using TIMS-MS. INTERNATIONAL JOURNAL FOR ION MOBILITY SPECTROMETRY : OFFICIAL PUBLICATION OF THE INTERNATIONAL SOCIETY FOR ION MOBILITY SPECTROMETRY 2016; 19:95-104. [PMID: 27818614 PMCID: PMC5091298 DOI: 10.1007/s12127-016-0201-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 05/26/2016] [Accepted: 05/29/2016] [Indexed: 01/02/2023]
Abstract
In the present work, we demonstrate the potential and versatility of TIMS for the analysis of proteins, DNA-protein complexes and protein-protein complexes in their native and denatured states. In addition, we show that accurate CCS measurement are possible and in good agreement with previously reported CCS values using other IMS analyzers (<5% difference). The main challenges for the analysis of high mass proteins and protein complexes in the mobility and m/z domain are described. That is, the analysis of high molecular weight systems in their native state may require the use of higher electric fields or a compromise in the TIMS mobility resolution by reducing the bath gas velocity in order to effectively trap at lower electric fields. This is the first report of CCS measurements of high molecular weight biomolecules and biomolecular complexes (~ 150 kDa) using TIMS-MS.
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Affiliation(s)
- Paolo Benigni
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Rebecca Marin
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
| | | | - Alyssa Garabedian
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
| | | | | | - Melvin A. Park
- Bruker Daltonics, Inc., Billerica, Massachusetts 01821, USA
| | - Francisco Fernandez-Lima
- Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Science Institute, Florida International University, Miami, FL 33199, USA
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36
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Bornschein RE, Niu S, Eschweiler J, Ruotolo BT. Ion Mobility-Mass Spectrometry Reveals Highly-Compact Intermediates in the Collision Induced Dissociation of Charge-Reduced Protein Complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:41-49. [PMID: 26323618 DOI: 10.1007/s13361-015-1250-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/30/2015] [Accepted: 08/01/2015] [Indexed: 06/04/2023]
Abstract
Protocols that aim to construct complete models of multiprotein complexes based on ion mobility and mass spectrometry data are becoming an important element of integrative structural biology efforts. However, the usefulness of such data is predicated, in part, on an ability to measure individual subunits removed from the complex while maintaining a compact/folded state. Gas-phase dissociation of intact complexes using collision induced dissociation is a potentially promising pathway for acquiring such protein monomer size information, but most product ions produced are possessed of high charge states and elongated/string-like conformations that are not useful in protein complex modeling. It has previously been demonstrated that the collision induced dissociation of charge-reduced protein complexes can produce compact subunit product ions; however, their formation mechanism is not well understood. Here, we present new experimental evidence for the avidin (64 kDa) and aldolase (157 kDa) tetramers that demonstrates significant complex remodeling during the dissociation of charge-reduced assemblies. Detailed analysis and modeling indicates that highly compact intermediates are accessed during the dissociation process by both complexes. Here, we present putative pathways that describe the formation of such ions, as well as discuss the broader significance of such data for structural biology applications moving forward.
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Affiliation(s)
| | - Shuai Niu
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Joseph Eschweiler
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA.
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37
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Hall Z, Schmidt C, Politis A. Uncovering the Early Assembly Mechanism for Amyloidogenic β2-Microglobulin Using Cross-linking and Native Mass Spectrometry. J Biol Chem 2015; 291:4626-37. [PMID: 26655720 PMCID: PMC4813486 DOI: 10.1074/jbc.m115.691063] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Indexed: 12/14/2022] Open
Abstract
β2-Microglobulin (β2m), a key component of the major histocompatibility class I complex, can aggregate into fibrils with severe clinical consequences. As such, investigating the structural aspects of the formation of oligomeric intermediates of β2m and their subsequent progression toward fibrillar aggregates is of great importance. However, β2m aggregates are challenging targets in structural biology, primarily due to their inherent transient and heterogeneous nature. Here we study the oligomeric distributions and structures of the early intermediates of amyloidogenic β2m and its truncated variant ΔN6-β2m. We established compact oligomers for both variants by integrating advanced mass spectrometric techniques with available electron microscopy maps and atomic level structures from NMR spectroscopy and x-ray crystallography. Our results revealed a stepwise assembly mechanism by monomer addition and domain swapping for the oligomeric species of ΔN6-β2m. The observed structural similarity and common oligomerization pathway between the two variants is likely to enable ΔN6-β2m to cross-seed β2m fibrillation and allow the formation of mixed fibrils. We further determined the key subunit interactions in ΔN6-β2m tetramer, revealing the importance of a domain-swapped hinge region for formation of higher order oligomers. Overall, we deliver new mechanistic insights into β2m aggregation, paving the way for future studies on the mechanisms and cause of amyloid fibrillation.
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Affiliation(s)
- Zoe Hall
- From the Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom, and
| | - Carla Schmidt
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom, and
| | - Argyris Politis
- Department of Chemistry, King's College London, 7 Trinity Street, London SE1 1DB, United Kingdom
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38
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Marcoux J, Cianférani S. Towards integrative structural mass spectrometry: Benefits from hybrid approaches. Methods 2015; 89:4-12. [DOI: 10.1016/j.ymeth.2015.05.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 05/06/2015] [Accepted: 05/25/2015] [Indexed: 01/10/2023] Open
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39
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Eschweiler JD, Rabuck-Gibbons JN, Tian Y, Ruotolo BT. CIUSuite: A Quantitative Analysis Package for Collision Induced Unfolding Measurements of Gas-Phase Protein Ions. Anal Chem 2015; 87:11516-22. [DOI: 10.1021/acs.analchem.5b03292] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Joseph D. Eschweiler
- University of Michigan Department
of Chemistry, Ann Arbor, Michigan 48109, United States
| | | | - Yuwei Tian
- University of Michigan Department
of Chemistry, Ann Arbor, Michigan 48109, United States
| | - Brandon T. Ruotolo
- University of Michigan Department
of Chemistry, Ann Arbor, Michigan 48109, United States
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40
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Campuzano IDG, Larriba C, Bagal D, Schnier PD. Ion Mobility and Mass Spectrometry Measurements of the Humanized IgGk NIST Monoclonal Antibody. ACTA ACUST UNITED AC 2015. [DOI: 10.1021/bk-2015-1202.ch004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Affiliation(s)
- Iain D. G. Campuzano
- Molecular Structure and Characterization, Amgen Inc., Thousand Oaks, California 91320, United States
- Mechanical Engineering Department, Yale University, New Haven, Connecticut 06520, United States
- Molecular Structure and Characterization, Amgen Inc., South San Francisco, California 94080, United States
| | - Carlos Larriba
- Molecular Structure and Characterization, Amgen Inc., Thousand Oaks, California 91320, United States
- Mechanical Engineering Department, Yale University, New Haven, Connecticut 06520, United States
- Molecular Structure and Characterization, Amgen Inc., South San Francisco, California 94080, United States
| | - Dhanashri Bagal
- Molecular Structure and Characterization, Amgen Inc., Thousand Oaks, California 91320, United States
- Mechanical Engineering Department, Yale University, New Haven, Connecticut 06520, United States
- Molecular Structure and Characterization, Amgen Inc., South San Francisco, California 94080, United States
| | - Paul D. Schnier
- Molecular Structure and Characterization, Amgen Inc., Thousand Oaks, California 91320, United States
- Mechanical Engineering Department, Yale University, New Haven, Connecticut 06520, United States
- Molecular Structure and Characterization, Amgen Inc., South San Francisco, California 94080, United States
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41
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Simon AL, Chirot F, Choi CM, Clavier C, Barbaire M, Maurelli J, Dagany X, MacAleese L, Dugourd P. Tandem ion mobility spectrometry coupled to laser excitation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:094101. [PMID: 26429458 DOI: 10.1063/1.4930604] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This manuscript describes a new experimental setup that allows to perform tandem ion mobility spectrometry (IMS) measurements and which is coupled to a high resolution time-of-flight mass spectrometer. It consists of two 79 cm long drift tubes connected by a dual ion funnel assembly. The setup was built to permit laser irradiation of the ions in the transfer region between the two drift tubes. This geometry allows selecting ions according to their ion mobility in the first drift tube, to irradiate selected ions, and examine the ion mobility of the product ions in the second drift tube. Activation by collision is possible in the same region (between the two tubes) and between the second tube and the time-of-flight. IMS-IMS experiments on Ubiquitin are reported. We selected a given isomer of charge state +7 and explored its structural rearrangement following collisional activation between the two drift tubes. An example of IMS-laser-IMS experiment is reported on eosin Y, where laser irradiation was used to produce radical ions by electron photodetachment starting from doubly deprotonated species. This allowed measuring the collision cross section of the radical photo-product, which cannot be directly produced with an electrospray source.
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Affiliation(s)
- Anne-Laure Simon
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Fabien Chirot
- Institut des Sciences Analytiques, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Chang Min Choi
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Christian Clavier
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Marc Barbaire
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Jacques Maurelli
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Xavier Dagany
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Luke MacAleese
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
| | - Philippe Dugourd
- Institut Lumière Matière, Université de Lyon, Université Lyon 1-CNRS, 69622 Villeurbanne cedex, France
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42
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Sinz A, Arlt C, Chorev D, Sharon M. Chemical cross-linking and native mass spectrometry: A fruitful combination for structural biology. Protein Sci 2015; 24:1193-209. [PMID: 25970732 PMCID: PMC4534171 DOI: 10.1002/pro.2696] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/14/2015] [Accepted: 04/29/2015] [Indexed: 12/31/2022]
Abstract
Mass spectrometry (MS) is becoming increasingly popular in the field of structural biology for analyzing protein three-dimensional-structures and for mapping protein-protein interactions. In this review, the specific contributions of chemical crosslinking and native MS are outlined to reveal the structural features of proteins and protein assemblies. Both strategies are illustrated based on the examples of the tetrameric tumor suppressor protein p53 and multisubunit vinculin-Arp2/3 hybrid complexes. We describe the distinct advantages and limitations of each technique and highlight synergistic effects when both techniques are combined. Integrating both methods is especially useful for characterizing large protein assemblies and for capturing transient interactions. We also point out the future directions we foresee for a combination of in vivo crosslinking and native MS for structural investigation of intact protein assemblies.
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Affiliation(s)
- Andrea Sinz
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Martin-Luther University Halle-WittenbergD-06120, Halle, Germany
| | - Christian Arlt
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Martin-Luther University Halle-WittenbergD-06120, Halle, Germany
| | - Dror Chorev
- Department of Biological Chemistry, Weizmann Institute of ScienceRehovot, 76100, Israel
| | - Michal Sharon
- Department of Biological Chemistry, Weizmann Institute of ScienceRehovot, 76100, Israel
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43
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Arndt JR, Kondalaji SG, Maurer MM, Parker A, Legleiter J, Valentine SJ. Huntingtin N-Terminal Monomeric and Multimeric Structures Destabilized by Covalent Modification of Heteroatomic Residues. Biochemistry 2015; 54:4285-96. [PMID: 26098795 DOI: 10.1021/acs.biochem.5b00478] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Early stage oligomer formation of the huntingtin protein may be driven by self-association of the 17-residue amphipathic α-helix at the protein's N-terminus (Nt17). Oligomeric structures have been implicated in neuronal toxicity and may represent important neurotoxic species in Huntington's disease. Therefore, a residue-specific structural characterization of Nt17 is crucial to understanding and potentially inhibiting oligomer formation. Native electrospray ion mobility spectrometry-mass spectrometry (IMS-MS) techniques and molecular dynamics simulations (MDS) have been applied to study coexisting monomer and multimer conformations of Nt17, independent of the remainder of huntingtin exon 1. MDS suggests gas-phase monomer ion structures comprise a helix-turn-coil configuration and a helix-extended-coil region. Elongated dimer species comprise partially helical monomers arranged in an antiparallel geometry. This stacked helical bundle may represent the earliest stages of Nt17-driven oligomer formation. Nt17 monomers and multimers have been further probed using diethylpyrocarbonate (DEPC). An N-terminal site (N-terminus of Threonine-3) and Lysine-6 are modified at higher DEPC concentrations, which led to the formation of an intermediate monomer structure. These modifications resulted in decreased extended monomer ion conformers, as well as a reduction in multimer formation. From the MDS experiments for the dimer ions, Lys6 residues in both monomer constituents interact with Ser16 and Glu12 residues on adjacent peptides; therefore, the decrease in multimer formation could result from disruption of these or similar interactions. This work provides a structurally selective model from which to study Nt17 self-association and provides critical insight toward Nt17 multimerization and, possibly, the early stages of huntingtin exon 1 aggregation.
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Affiliation(s)
- James R Arndt
- †C. Eugene Bennett Department of Chemistry, ‡WVNano Safe Initiative, and §The Center for Neuroscience, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Samaneh Ghassabi Kondalaji
- †C. Eugene Bennett Department of Chemistry, ‡WVNano Safe Initiative, and §The Center for Neuroscience, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Megan M Maurer
- †C. Eugene Bennett Department of Chemistry, ‡WVNano Safe Initiative, and §The Center for Neuroscience, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Arlo Parker
- †C. Eugene Bennett Department of Chemistry, ‡WVNano Safe Initiative, and §The Center for Neuroscience, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Justin Legleiter
- †C. Eugene Bennett Department of Chemistry, ‡WVNano Safe Initiative, and §The Center for Neuroscience, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Stephen J Valentine
- †C. Eugene Bennett Department of Chemistry, ‡WVNano Safe Initiative, and §The Center for Neuroscience, West Virginia University, Morgantown, West Virginia 26506, United States
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44
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Bleiholder C, Johnson NR, Contreras S, Wyttenbach T, Bowers MT. Molecular Structures and Ion Mobility Cross Sections: Analysis of the Effects of He and N2 Buffer Gas. Anal Chem 2015; 87:7196-203. [DOI: 10.1021/acs.analchem.5b01429] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Christian Bleiholder
- Department of Chemistry and
Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Nicholas R. Johnson
- Department of Chemistry and
Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Stephanie Contreras
- Department of Chemistry and
Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Thomas Wyttenbach
- Department of Chemistry and
Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Michael T. Bowers
- Department of Chemistry and
Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
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45
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Distinct higher-order α-synuclein oligomers induce intracellular aggregation. Biochem J 2015; 468:485-93. [DOI: 10.1042/bj20150159] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/08/2015] [Indexed: 12/12/2022]
Abstract
The cell-to-cell transmission of pathology in Parkinson's disease has been linked to soluble amyloid oligomers. Ion mobility spectrometry (IMS)–MS has been used to show that these soluble oligomers have a compact ring-like conformation.
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46
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D'Atri V, Porrini M, Rosu F, Gabelica V. Linking molecular models with ion mobility experiments. Illustration with a rigid nucleic acid structure. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:711-26. [PMID: 26259654 PMCID: PMC4440389 DOI: 10.1002/jms.3590] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Revised: 03/04/2015] [Accepted: 03/04/2015] [Indexed: 05/13/2023]
Abstract
Ion mobility spectrometry experiments allow the mass spectrometrist to determine an ion's rotationally averaged collision cross section Ω(EXP). Molecular modelling is used to visualize what ion three-dimensional structure(s) is(are) compatible with the experiment. The collision cross sections of candidate molecular models have to be calculated, and the resulting Ω(CALC) are compared with the experimental data. Researchers who want to apply this strategy to a new type of molecule face many questions: (1) What experimental error is associated with Ω(EXP) determination, and how to estimate it (in particular when using a calibration for traveling wave ion guides)? (2) How to generate plausible 3D models in the gas phase? (3) Different collision cross section calculation models exist, which have been developed for other analytes than mine. Which one(s) can I apply to my systems? To apply ion mobility spectrometry to nucleic acid structural characterization, we explored each of these questions using a rigid structure which we know is preserved in the gas phase: the tetramolecular G-quadruplex [dTGGGGT]4, and we will present these detailed investigation in this tutorial.
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Affiliation(s)
- Valentina D'Atri
- Univ. Bordeaux, IECB, ARNA laboratoryPessac, F-33600, France
- INSERM, U869, ARNA laboratoryBordeaux, F-33000, France
| | - Massimiliano Porrini
- Univ. Bordeaux, IECB, ARNA laboratoryPessac, F-33600, France
- INSERM, U869, ARNA laboratoryBordeaux, F-33000, France
| | | | - Valérie Gabelica
- Univ. Bordeaux, IECB, ARNA laboratoryPessac, F-33600, France
- INSERM, U869, ARNA laboratoryBordeaux, F-33000, France
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47
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Politis A, Borysik AJ. Assembling the pieces of macromolecular complexes: Hybrid structural biology approaches. Proteomics 2015; 15:2792-803. [DOI: 10.1002/pmic.201400507] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/26/2015] [Accepted: 02/24/2015] [Indexed: 01/14/2023]
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48
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Maurer MM, Donohoe GC, Valentine SJ. Advances in ion mobility-mass spectrometry instrumentation and techniques for characterizing structural heterogeneity. Analyst 2015; 140:6782-98. [PMID: 26114255 DOI: 10.1039/c5an00922g] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Enabling IM-MS instrumentation and techniques for characterizing sample structural heterogeneity have developed rapidly over the last five years.
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Affiliation(s)
- Megan M. Maurer
- C. Eugene Bennett Department of Chemistry
- West Virginia University
- Morgantown
- USA
| | - Gregory C. Donohoe
- C. Eugene Bennett Department of Chemistry
- West Virginia University
- Morgantown
- USA
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49
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Topological models of heteromeric protein assemblies from mass spectrometry: application to the yeast eIF3:eIF5 complex. ACTA ACUST UNITED AC 2014; 22:117-28. [PMID: 25544043 PMCID: PMC4306531 DOI: 10.1016/j.chembiol.2014.11.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 10/07/2014] [Accepted: 11/07/2014] [Indexed: 02/05/2023]
Abstract
Describing, understanding, and modulating the function of the cell require elucidation of the structures of macromolecular assemblies. Here, we describe an integrative method for modeling heteromeric complexes using as a starting point disassembly pathways determined by native mass spectrometry (MS). In this method, the pathway data and other available information are encoded as a scoring function on the positions of the subunits of the complex. The method was assessed on its ability to reproduce the native contacts in five benchmark cases with simulated MS data and two cases with real MS data. To illustrate the power of our method, we purified the yeast initiation factor 3 (eIF3) complex and characterized it by native MS and chemical crosslinking MS. We established substoichiometric binding of eIF5 and derived a model for the five-subunit eIF3 complex, at domain level, consistent with its role as a scaffold for other initiation factors. Integrative MS method allows topological characterization of heteromeric complexes Intersubunit crosslinks increase the precision of the predicted topologies A 3D model of eIF3:eIF5 complex was built using restraints from MS-based methods Integrative modeling reveals two submodules within eIF3: eIF3b:i:g and eIF3a:c
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50
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Stow SM, Goodwin CR, Kliman M, Bachmann BO, McLean JA, Lybrand TP. Distance geometry protocol to generate conformations of natural products to structurally interpret ion mobility-mass spectrometry collision cross sections. J Phys Chem B 2014; 118:13812-20. [PMID: 25360896 PMCID: PMC4259499 DOI: 10.1021/jp509398e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Ion mobility-mass spectrometry (IM-MS)
allows the separation of
ionized molecules based on their charge-to-surface area (IM) and mass-to-charge
ratio (MS), respectively. The IM drift time data that is obtained
is used to calculate the ion-neutral collision cross section (CCS)
of the ionized molecule with the neutral drift gas, which is directly
related to the ion conformation and hence molecular size and shape.
Studying the conformational landscape of these ionized molecules computationally
provides interpretation to delineate the potential structures that
these CCS values could represent, or conversely, structural motifs
not consistent with the IM data. A challenge in the IM-MS community
is the ability to rapidly compute conformations to interpret natural
product data, a class of molecules exhibiting a broad range of biological
activity. The diversity of biological activity is, in part, related
to the unique structural characteristics often observed for natural
products. Contemporary approaches to structurally interpret IM-MS
data for peptides and proteins typically utilize molecular dynamics
(MD) simulations to sample conformational space. However, MD calculations
are computationally expensive, they require a force field that accurately
describes the molecule of interest, and there is no simple metric
that indicates when sufficient conformational sampling has been achieved.
Distance geometry is a computationally inexpensive approach that creates
conformations based on sampling different pairwise distances between
the atoms within the molecule and therefore does not require a force
field. Progressively larger distance bounds can be used in distance
geometry calculations, providing in principle a strategy to assess
when all plausible conformations have been sampled. Our results suggest
that distance geometry is a computationally efficient and potentially
superior strategy for conformational analysis of natural products
to interpret gas-phase CCS data.
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Affiliation(s)
- Sarah M Stow
- Department of Chemistry, ‡Department of Pharmacology, §Vanderbilt Institute of Chemical Biology, ∥Vanderbilt Institute of Integrative Biosystems Research and Education, ⊥Center for Structural Biology, Vanderbilt University , Nashville, Tennessee 37235, United States
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