1
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Baines C, Sargeant J, Fage CD, Pugh H, Alkhalaf LM, Challis GL, Oldham NJ. Native ESI-MS and Collision-Induced Unfolding (CIU) of the Complex between Bacterial Elongation Factor-Tu and the Antibiotic Enacyloxin IIa. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1490-1496. [PMID: 38830009 PMCID: PMC11228974 DOI: 10.1021/jasms.4c00087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/09/2024] [Accepted: 05/20/2024] [Indexed: 06/05/2024]
Abstract
Collision-induced unfolding (CIU) of protein ions, monitored by ion mobility-mass spectrometry, can be used to assess the stability of their compact gas-phase fold and hence provide structural information. The bacterial elongation factor EF-Tu, a key protein for mRNA translation in prokaryotes and hence a promising antibiotic target, has been studied by CIU. The major [M + 12H]12+ ion of EF-Tu unfolded in collision with Ar atoms between 40 and 50 V, corresponding to an Elab energy of 480-500 eV. Binding of the cofactor analogue GDPNP and the antibiotic enacyloxin IIa stabilized the compact fold of EF-Tu, although dissociation of the latter from the complex diminished its stabilizing effect at higher collision energies. Molecular dynamics simulations of the [M + 12H]12+ EF-Tu ion showed similar qualitative behavior to the experimental results.
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Affiliation(s)
- Cameron Baines
- School
of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United
Kingdom
| | - Jacob Sargeant
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Christopher D. Fage
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Hannah Pugh
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Lona M. Alkhalaf
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Gregory L. Challis
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
- Warwick
Integrative Synthetic Biology Centre, University
of Warwick, Coventry CV4 7AL, United Kingdom
- Department
of Biochemistry and Molecular Biology, Biomedicine Discovery Institute,
Monash University, Clayton, Victoria 3800, Australia
- ARC
Centre of Excellence for Innovations in Peptide and Protein Science, Monash University, Clayton, Victoria 3800, Australia
| | - Neil J. Oldham
- School
of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United
Kingdom
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2
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Sahin C, Leppert A, Landreh M. Advances in mass spectrometry to unravel the structure and function of protein condensates. Nat Protoc 2023; 18:3653-3661. [PMID: 37907762 DOI: 10.1038/s41596-023-00900-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 08/09/2023] [Indexed: 11/02/2023]
Abstract
Membrane-less organelles assemble through liquid-liquid phase separation (LLPS) of partially disordered proteins into highly specialized microenvironments. Currently, it is challenging to obtain a clear understanding of the relationship between the structure and function of phase-separated protein assemblies, owing to their size, dynamics and heterogeneity. In this Perspective, we discuss recent advances in mass spectrometry (MS) that offer several promising approaches for the study of protein LLPS. We survey MS tools that have provided valuable insights into other insoluble protein systems, such as amyloids, and describe how they can also be applied to study proteins that undergo LLPS. On the basis of these recent advances, we propose to integrate MS into the experimental workflow for LLPS studies. We identify specific challenges and future opportunities for the analysis of protein condensate structure and function by MS.
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Affiliation(s)
- Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet-Biomedicum, Solna, Sweden.
- Structural Biology and NMR laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | - Axel Leppert
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet-Biomedicum, Solna, Sweden
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet-Biomedicum, Solna, Sweden.
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
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3
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Liu FC, Cropley TC, Bleiholder C. Elucidating Structures of Protein Complexes by Collision-Induced Dissociation at Elevated Gas Pressures. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:2247-2258. [PMID: 37729591 PMCID: PMC11162217 DOI: 10.1021/jasms.3c00191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Ion activation methods carried out at gas pressures compatible with ion mobility separations are not yet widely established. This limits the analytical utility of emerging tandem-ion mobility spectrometers that conduct multiple ion mobility separations in series. The present work investigates the applicability of collision-induced dissociation (CID) at 1 to 3 mbar in a tandem-trapped ion mobility spectrometer (tandem-TIMS) to study the architecture of protein complexes. We show that CID of the homotetrameric protein complexes streptavidin (53 kDa), neutravidin (60 kDa), and concanavalin A (110 kDa) provides access to all subunits of the investigated protein complexes, including structurally informative dimers. We report on an "atypical" dissociation pathway, which for concanavalin A proceeds via symmetric partitioning of the precursor charges and produces dimers with the same charge states that were previously reported from surface induced dissociation. Our data suggest a correlation between the formation of subunits by CID in tandem-TIMS/MS, their binding strengths in the native tetramer structures, and the applied activation voltage. Ion mobility spectra of in situ-generated subunits reveal a marked structural heterogeneity inconsistent with annealing into their most stable gas phase structures. Structural transitions are observed for in situ-generated subunits that resemble the transitions reported from collision-induced unfolding of natively folded proteins. These observations indicate that some aspects of the native precursor structure is preserved in the subunits generated from disassembly of the precursor complex. We rationalize our observations by an approximately 100-fold shorter activation time scale in comparison to traditional CID in a collision cell. Finally, the approach discussed here to conduct CID at elevated pressures appears generally applicable also for other types of tandem-ion mobility spectrometers.
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Affiliation(s)
- Fanny C. Liu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Tyler C. Cropley
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Christian Bleiholder
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
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4
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Jia M, Song Y, Du C, Wysocki VH. Oxidized and Reduced Dimeric Protein Complexes Illustrate Contrasting CID and SID Charge Partitioning. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:2166-2175. [PMID: 37590530 DOI: 10.1021/jasms.3c00142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Charge partitioning during the dissociation of protein complexes in the gas phase is influenced by many factors, such as interfacial interactions, protein flexibility, protein conformation, and dissociation methods. In the present work, two cysteine-containing homodimer proteins, β-lactoglobulin and α-lactalbumin, with the disulfide bonds intact and reduced, were used to gain insight into the charge partitioning behaviors of collision-induced dissociation (CID) and surface-induced dissociation (SID) processes. For these proteins, we find that restructuring dominates with CID and dissociation with symmetric charge partitioning dominates with SID, regardless of whether intramolecular disulfide bonds are oxidized or reduced. CID of the charge-reduced dimeric protein complex leads to a precursor with a slightly smaller collision cross section (CCS), greater stability, and more symmetrically distributed charges than the significantly expanded form produced by CID of the higher charged dimer. Collision-induced unfolding plots demonstrate that the unfolding-restructuring of the protein complexes initiates the charge migration of higher charge-state precursors. Overall, gas collisions reveal the charge-dependent restructuring/unfolding properties of the protein precursor, while surface collisions lead predominantly to more charge-symmetric monomer separation. CID's multiple low-energy collisions sequentially reorganize intra- and intermolecular bonds, while SID's large-step energy jump cleaves intermolecular interfacial bonds in preference to reorganizing intramolecular bonds. The activated population of precursors that have taken on energy without dissociating (populated in CID over a wide range of collision energies, populated in SID for only a narrow distribution of collision energies near the onset of dissociation) is expected to be restructured, regardless of the activation method.
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Affiliation(s)
- Mengxuan Jia
- The Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yang Song
- The Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Chen Du
- The Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Vicki H Wysocki
- The Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, Ohio 43210, United States
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5
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Mathew A, Giskes F, Lekkas A, Greisch JF, Eijkel GB, Anthony IGM, Fort K, Heck AJR, Papanastasiou D, Makarov AA, Ellis SR, Heeren RMA. An Orbitrap/Time-of-Flight Mass Spectrometer for Photofragment Ion Imaging and High-Resolution Mass Analysis of Native Macromolecular Assemblies. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023. [PMID: 37319176 DOI: 10.1021/jasms.3c00053] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
We discuss the design, development, and evaluation of an Orbitrap/time-of-flight (TOF) mass spectrometry (MS)-based instrument with integrated UV photodissociation (UVPD) and time/mass-to-charge ratio (m/z)-resolved imaging for the comprehensive study of the higher-order molecular structure of macromolecular assemblies (MMAs). A bespoke TOF analyzer has been coupled to the higher-energy collisional dissociation cell of an ultrahigh mass range hybrid quadrupole-Orbitrap MS. A 193 nm excimer laser was employed to photofragment MMA ions. A combination of microchannel plates (MCPs)-Timepix (TPX) quad and MCPs-phosphor screen-TPX3CAM assemblies have been used as axial and orthogonal imaging detectors, respectively. The instrument can operate in four different modes, where the UVPD-generated fragment ions from the native MMA ions can be measured with high-mass resolution or imaged in a mass-resolved manner to reveal the relative positions of the UVPD fragments postdissociation. This information is intended to be utilized for retrieving higher-order molecular structural details that include the conformation, subunit stoichiometry, and molecular interactions as well as to understand the dissociation dynamics of the MMAs in the gas phase.
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Affiliation(s)
- Anjusha Mathew
- Maastricht MultiModal Molecular Imaging (M4i) Institute, Division of Imaging Mass Spectrometry (IMS), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Frans Giskes
- Maastricht MultiModal Molecular Imaging (M4i) Institute, Division of Imaging Mass Spectrometry (IMS), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Alexandros Lekkas
- Fasmatech Science and Technology, Demokritos NCSR, 15310 Agia Paraskevi, Athens, Greece
| | - Jean-François Greisch
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Centre for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Gert B Eijkel
- Maastricht MultiModal Molecular Imaging (M4i) Institute, Division of Imaging Mass Spectrometry (IMS), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Ian G M Anthony
- Maastricht MultiModal Molecular Imaging (M4i) Institute, Division of Imaging Mass Spectrometry (IMS), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Kyle Fort
- Thermo Fisher Scientific (Bremen) GmbH, 28199 Bremen, Germany
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Centre for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | | | - Alexander A Makarov
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Centre for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
- Thermo Fisher Scientific (Bremen) GmbH, 28199 Bremen, Germany
| | - Shane R Ellis
- Maastricht MultiModal Molecular Imaging (M4i) Institute, Division of Imaging Mass Spectrometry (IMS), Maastricht University, 6229 ER Maastricht, The Netherlands
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Ron M A Heeren
- Maastricht MultiModal Molecular Imaging (M4i) Institute, Division of Imaging Mass Spectrometry (IMS), Maastricht University, 6229 ER Maastricht, The Netherlands
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6
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Sahin C, Motso A, Gu X, Feyrer H, Lama D, Arndt T, Rising A, Gese GV, Hällberg BM, Marklund EG, Schafer NP, Petzold K, Teilum K, Wolynes PG, Landreh M. Mass Spectrometry of RNA-Binding Proteins during Liquid-Liquid Phase Separation Reveals Distinct Assembly Mechanisms and Droplet Architectures. J Am Chem Soc 2023; 145:10659-10668. [PMID: 37145883 DOI: 10.1021/jacs.3c00932] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Liquid-liquid phase separation (LLPS) of heterogeneous ribonucleoproteins (hnRNPs) drives the formation of membraneless organelles, but structural information about their assembled states is still lacking. Here, we address this challenge through a combination of protein engineering, native ion mobility mass spectrometry, and molecular dynamics simulations. We used an LLPS-compatible spider silk domain and pH changes to control the self-assembly of the hnRNPs FUS, TDP-43, and hCPEB3, which are implicated in neurodegeneration, cancer, and memory storage. By releasing the proteins inside the mass spectrometer from their native assemblies, we could monitor conformational changes associated with liquid-liquid phase separation. We find that FUS monomers undergo an unfolded-to-globular transition, whereas TDP-43 oligomerizes into partially disordered dimers and trimers. hCPEB3, on the other hand, remains fully disordered with a preference for fibrillar aggregation over LLPS. The divergent assembly mechanisms revealed by ion mobility mass spectrometry of soluble protein species that exist under LLPS conditions suggest structurally distinct complexes inside liquid droplets that may impact RNA processing and translation depending on biological context.
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Affiliation(s)
- Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen, Denmark
| | - Aikaterini Motso
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
| | - Xinyu Gu
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Hannes Feyrer
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
| | - Dilraj Lama
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
| | - Tina Arndt
- Department of Biosciences and Nutrition, Karolinska Institutet, S-141 57 Huddinge, Sweden
| | - Anna Rising
- Department of Biosciences and Nutrition, Karolinska Institutet, S-141 57 Huddinge, Sweden
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Box 7011, S-750 07 Uppsala, Sweden
| | - Genis Valentin Gese
- Department of Cell and Molecular Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 171 65 Stockholm, Sweden
| | - B Martin Hällberg
- Department of Cell and Molecular Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 171 65 Stockholm, Sweden
| | - Erik G Marklund
- Department of Chemistry - BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Nicholas P Schafer
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Katja Petzold
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
- Department of Medical Biochemistry and Microbiology, Uppsala University, 751 24 Uppsala, Sweden
| | - Kaare Teilum
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen, Denmark
| | - Peter G Wolynes
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
- Department of Cell- and Molecular Biology, Uppsala University, Box 596, 751 24 Uppsala, Sweden
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7
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Schrader RL, Walker TE, Russell DH. Modified Ion Source for the Improved Collisional Activation of Protein Complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:977-980. [PMID: 37001029 PMCID: PMC10510017 DOI: 10.1021/jasms.3c00071] [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] [Indexed: 05/04/2023]
Abstract
The analysis of large molecules is challenging, as they often have salts and adducts retained through the electrospray process, which increase the observed mass and compromise the achievable mass resolution. Mild collisional activation has been shown to be very effective for the removal of adducts and increases both measurement accuracy and mass resolution of large (>100 kDa) protein complexes. Collisionally activated protein ions are more completely desolvated due to the increased number of collisions when trapped following activation. A short square quadrupole maintained at 300 mTorr by a mechanical pump was added between the ion funnel and transmission quadrupole. This configuration and operation effectively removed adducts from the 800 kDa tetradecamer GroEL as well as fragmented smaller protein complexes like C-reactive protein. Due to the gas high pressure, ions of low size-to-charge ratio, such as those in charge reducing buffers, had low ejection efficiency. We show that segmenting the quadrupole rods greatly improves signal intensity for charge reduced GroEL D398A mutant compared to nonsegmented rods when operating at high pressure.
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Affiliation(s)
- Robert L Schrader
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Thomas E Walker
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - David H Russell
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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8
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Reid DJ, Thibert S, Zhou M. Dissecting the structural heterogeneity of proteins by native mass spectrometry. Protein Sci 2023; 32:e4612. [PMID: 36851867 PMCID: PMC10031758 DOI: 10.1002/pro.4612] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/01/2023]
Abstract
A single gene yields many forms of proteins via combinations of post-transcriptional/post-translational modifications. Proteins also fold into higher-order structures and interact with other molecules. The combined molecular diversity leads to the heterogeneity of proteins that manifests as distinct phenotypes. Structural biology has generated vast amounts of data, effectively enabling accurate structural prediction by computational methods. However, structures are often obtained heterologously under homogeneous states in vitro. The lack of native heterogeneity under cellular context creates challenges in precisely connecting the structural data to phenotypes. Mass spectrometry (MS) based proteomics methods can profile proteome composition of complex biological samples. Most MS methods follow the "bottom-up" approach, which denatures and digests proteins into short peptide fragments for ease of detection. Coupled with chemical biology approaches, higher-order structures can be probed via incorporation of covalent labels on native proteins that are maintained at the peptide level. Alternatively, native MS follows the "top-down" approach and directly analyzes intact proteins under nondenaturing conditions. Various tandem MS activation methods can dissect the intact proteins for in-depth structural elucidation. Herein, we review recent native MS applications for characterizing heterogeneous samples, including proteins binding to mixtures of ligands, homo/hetero-complexes with varying stoichiometry, intrinsically disordered proteins with dynamic conformations, glycoprotein complexes with mixed modification states, and active membrane protein complexes in near-native membrane environments. We summarize the benefits, challenges, and ongoing developments in native MS, with the hope to demonstrate an emerging technology that complements other tools by filling the knowledge gaps in understanding molecular heterogeneity of proteins. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Deseree J Reid
- Chemical and Biological Signature Sciences, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Stephanie Thibert
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Mowei Zhou
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
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9
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Tiefenthaler L, Scheier P, Erdmann E, Aguirre NF, Díaz-Tendero S, Luxford TFM, Kočišek J. Non-ergodic fragmentation upon collision-induced activation of cysteine-water cluster cations. Phys Chem Chem Phys 2023; 25:5361-5371. [PMID: 36647750 PMCID: PMC9930733 DOI: 10.1039/d2cp04172c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Cysteine-water cluster cations Cys(H2O)3,6+ and Cys(H2O)3,6H+ are assembled in He droplets and probed by tandem mass spectrometry with collision-induced activation. Benchmark experimental data for this biologically important system are complemented with theory to elucidate the details of the collision-induced activation process. Experimental energy thresholds for successive release of water are compared to water dissociation energies from DFT calculations showing that clusters do not only fragment exclusively by sequential emission of single water molecules but also by the release of small water clusters. Release of clustered water is observed also in the ADMP (atom centered density matrix propagation) molecular dynamics model of small Cys(H2O)3+ and Cys(H2O)3H+ clusters. For large clusters Cys(H2O)6+ and Cys(H2O)6H+ the less computationally demanding statistical Microcanonical Metropolis Monte-Carlo method (M3C) is used to model the experimental fragmentation patterns. We are able to detail the energy redistribution in clusters upon collision activation. In the present case, about two thirds of the collision energy redistribute via an ergodic process, while the remaining one third is transferred into a non-ergodic channel leading to ejection of a single water molecule from the cluster. In contrast to molecular fragmentation, which can be well described by statistical models, modelling of collision-induced activation of weakly bound clusters requires inclusion of non-ergodic processes.
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Affiliation(s)
- Lukas Tiefenthaler
- Institute for Ion Physics and Applied Physics, University of Innsbruck, Austria.
| | - Paul Scheier
- Institute for Ion Physics and Applied Physics, University of Innsbruck, Austria.
| | - Ewa Erdmann
- Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland.,Departamento de Química, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
| | | | - Sergio Díaz-Tendero
- Departamento de Química, Universidad Autónoma de Madrid, 28049, Madrid, Spain. .,Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.,Institute for Advanced Research in ChemicalSciences (IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Thomas F. M. Luxford
- J. Heyrovský Institute of Physical Chemistry v.v.i., The Czech Academy of SciencesDolejškova 318223 PragueCzechia
| | - Jaroslav Kočišek
- J. Heyrovský Institute of Physical Chemistry v.v.i., The Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czechia.
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10
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Schrader R, Walker TE, Chakravorty S, Anderson GA, Reilly PTA, Russell DH. Optimization of a Digital Mass Filter for the Isolation of Intact Protein Complexes in Stability Zone 1,1. Anal Chem 2023; 95:3062-3068. [PMID: 36701646 PMCID: PMC9983038 DOI: 10.1021/acs.analchem.2c05221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 01/13/2023] [Indexed: 01/27/2023]
Abstract
Digital mass filters are advantageous for the analysis of large molecules due to the ability to perform ion isolation of high-m/z ions without the generation of very high radio frequency (RF) and DC voltages. Experimentally determined Mathieu stability diagrams of stability zone 1,1 for capacitively coupled digital waveforms show a voltage offset between the quadrupole rod pairs is introduced by the capacitors which is dependent on the voltage magnitude of the waveform and the duty cycle. This changes the ion's a value from a = 0 to a < 0. These effects are illustrated for isolation for single-charge states for various protein complexes up to 800 kDa (GroEL) for stability zone 1,1. Isolation resolving power (m/Δm) of approximately 280 was achieved for an ion of m/z 12,315 (z = 65+ for 800.5 kDa GroEL D398A), which corresponds to an m/z window of 44.
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Affiliation(s)
- Robert
L. Schrader
- Department
of Chemistry, Texas A&M University, College Station, Texas77843, United States
| | - Thomas E. Walker
- Department
of Chemistry, Texas A&M University, College Station, Texas77843, United States
| | - Sumeet Chakravorty
- Department
of Chemistry, Washington State University, Pullman, Washington99164, United States
| | | | - Peter T. A. Reilly
- Department
of Chemistry, Washington State University, Pullman, Washington99164, United States
| | - David H. Russell
- Department
of Chemistry, Texas A&M University, College Station, Texas77843, United States
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11
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Saluri M, Leppert A, Gese GV, Sahin C, Lama D, Kaldmäe M, Chen G, Elofsson A, Allison TM, Arsenian-Henriksson M, Johansson J, Lane DP, Hällberg BM, Landreh M. A "grappling hook" interaction connects self-assembly and chaperone activity of Nucleophosmin 1. PNAS NEXUS 2023; 2:pgac303. [PMID: 36743470 PMCID: PMC9896144 DOI: 10.1093/pnasnexus/pgac303] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 01/05/2023] [Indexed: 01/11/2023]
Abstract
How the self-assembly of partially disordered proteins generates functional compartments in the cytoplasm and particularly in the nucleus is poorly understood. Nucleophosmin 1 (NPM1) is an abundant nucleolar protein that forms large oligomers and undergoes liquid-liquid phase separation by binding RNA or ribosomal proteins. It provides the scaffold for ribosome assembly but also prevents protein aggregation as part of the cellular stress response. Here, we use aggregation assays and native mass spectrometry (MS) to examine the relationship between the self-assembly and chaperone activity of NPM1. We find that oligomerization of full-length NPM1 modulates its ability to retard amyloid formation in vitro. Machine learning-based structure prediction and cryo-electron microscopy reveal fuzzy interactions between the acidic disordered region and the C-terminal nucleotide-binding domain, which cross-link NPM1 pentamers into partially disordered oligomers. The addition of basic peptides results in a tighter association within the oligomers, reducing their capacity to prevent amyloid formation. Together, our findings show that NPM1 uses a "grappling hook" mechanism to form a network-like structure that traps aggregation-prone proteins. Nucleolar proteins and RNAs simultaneously modulate the association strength and chaperone activity, suggesting a mechanism by which nucleolar composition regulates the chaperone activity of NPM1.
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Affiliation(s)
- Mihkel Saluri
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet – Biomedicum, Solnavägen 9, 171 65 Solna, Stockholm, Sweden
| | | | | | - Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet – Biomedicum, Solnavägen 9, 171 65 Solna, Stockholm, Sweden,Structural Biology and NMR laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen, Denmark
| | - Dilraj Lama
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet – Biomedicum, Solnavägen 9, 171 65 Solna, Stockholm, Sweden
| | - Margit Kaldmäe
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet – Biomedicum, Solnavägen 9, 171 65 Solna, Stockholm, Sweden
| | - Gefei Chen
- Department of Biosciences and Nutrition, Karolinska Institutet, 141 57 Huddinge,, Sweden
| | - Arne Elofsson
- Science for Life Laboratory and Department of Biochemistry and Biophysics, Stockholm University, 114 19 Stockholm, Sweden
| | - Timothy M Allison
- Biomolecular Interaction Centre, School of Physical and Chemical Sciences, University of Canterbury, Upper Riccarton, Christchurch 8041, New Zealand
| | - Marie Arsenian-Henriksson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet – Biomedicum, Solnavägen 9, 171 65 Solna, Stockholm, Sweden
| | - Jan Johansson
- Department of Biosciences and Nutrition, Karolinska Institutet, 141 57 Huddinge,, Sweden
| | - David P Lane
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet – Biomedicum, Solnavägen 9, 171 65 Solna, Stockholm, Sweden
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12
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Ramírez CR, Murtada R, Gao J, Ruotolo BT. Free Radical-Based Sequencing for Native Top-Down Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:2283-2290. [PMID: 36346751 PMCID: PMC10202123 DOI: 10.1021/jasms.2c00252] [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] [Indexed: 05/03/2023]
Abstract
Native top-down proteomics allows for both proteoform identification and high-order structure characterization for cellular protein complexes. Unfortunately, tandem MS-based fragmentation efficiencies for such targets are low due to an increase in analyte ion mass and the low ion charge states that characterize native MS data. Multiple fragmentation methods can be integrated in order to increase protein complex sequence coverage, but this typically requires use of specialized hardware and software. Free-radical-initiated peptide sequencing (FRIPS) enables access to charge-remote and electron-based fragmentation channels within the context of conventional CID experiments. Here, we optimize FRIPS labeling for native top-down sequencing experiments. Our labeling approach is able to access intact complexes with TEMPO-based FRIPS reagents without significant protein denaturation or assembly disruption. By combining CID and FRIPS datasets, we observed sequence coverage improvements as large as 50% for protein complexes ranging from 36 to 106 kDa. Fragment ion production in these experiments was increased by as much as 102%. In general, our results indicate that TEMPO-based FRIPS reagents have the potential to dramatically increase sequence coverage obtained in native top-down experiments.
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Affiliation(s)
- Carolina Rojas Ramírez
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Rayan Murtada
- Department of Chemistry & Biochemistry, Montclair State University, Montclair NJ 07043, United States
| | - Jinshan Gao
- Department of Chemistry & Biochemistry, Montclair State University, Montclair NJ 07043, United States
| | - Brandon T. Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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13
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Nash S, Vachet RW. Gas-Phase Unfolding of Protein Complexes Distinguishes Conformational Isomers. J Am Chem Soc 2022; 144:22128-22139. [PMID: 36414315 DOI: 10.1021/jacs.2c09573] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Proteins can adopt different conformational states that are important for their biological function and, in some cases, can be responsible for their dysfunction. The essential roles that proteins play in biological systems make distinguishing the structural differences between these conformational states both fundamentally and practically important. Here, we demonstrate that collision-induced unfolding (CIU), in combination with ion mobility-mass spectrometry (IM-MS) measurements, distinguish subtly different conformational states for protein complexes. Using the open and closed states of the β-lactoglobulin (βLG) dimer as a model, we show that these two conformational isomers unfold during collisional activation to generate distinct states that are readily separated by IM-MS. Extensive molecular modeling of the CIU process reproduces the distinct unfolding intermediates and identifies the molecular details that explain why the two conformational states unfold in distinct ways. Strikingly, the open conformational state forms new electrostatic interactions upon collisional heating, while the closed state does not. These newly formed electrostatic interactions involve residues on the loop differentially positioned in the two βLG conformational isomers, highlighting that gas-phase unfolding pathways reflect aspects of solution structure. This combination of experiment and theory provides a path forward for distinguishing subtly different conformational isomers for protein complexes via gas-phase unfolding experiments. Our results also have implications for understanding how protein complexes dissociate in the gas phase, indicating that current models need to be refined to explain protein complex dissociation.
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Affiliation(s)
- Stacey Nash
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Richard W Vachet
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States.,Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003 United States
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14
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Parvate AD, Powell SM, Brookreson JT, Moser TH, Novikova IV, Zhou M, Evans JE. Cryo-EM structure of the diapause chaperone artemin. Front Mol Biosci 2022; 9:998562. [DOI: 10.3389/fmolb.2022.998562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 11/01/2022] [Indexed: 11/29/2022] Open
Abstract
The protein artemin acts as both an RNA and protein chaperone and constitutes over 10% of all protein in Artemia cysts during diapause. However, its mechanistic details remain elusive since no high-resolution structure of artemin exists. Here we report the full-length structure of artemin at 2.04 Å resolution. The cryo-EM map contains density for an intramolecular disulfide bond between Cys22-Cys61 and resolves the entire C-terminus extending into the core of the assembled protein cage but in a different configuration than previously hypothesized with molecular modeling. We also provide data supporting the role of C-terminal helix F towards stabilizing the dimer form that is believed to be important for its chaperoning activity. We were able to destabilize this effect by placing a tag at the C-terminus to fully pack the internal cavity and cause limited steric hindrance.
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15
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Eldrid C, Cragnolini T, Ben-Younis A, Zou J, Raleigh DP, Thalassinos K. Linking Gas-Phase and Solution-Phase Protein Unfolding via Mobile Proton Simulations. Anal Chem 2022; 94:16113-16121. [DOI: 10.1021/acs.analchem.2c03352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Charles Eldrid
- School of Biological Sciences, University of Southampton, SouthamptonSO16 1BJ, U.K
- Institute of Structural and Molecular Biology, Division of Bioscience, University College London, LondonWC1E 6BT, U.K
| | - Tristan Cragnolini
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, LondonWC1E 7HX, U.K
| | - Aisha Ben-Younis
- Institute of Structural and Molecular Biology, Division of Bioscience, University College London, LondonWC1E 6BT, U.K
| | - Junjie Zou
- Department of Chemistry, Stony Brook University, 100 Nicolls Rd., Stony Brook, New York11794, United States
| | - Daniel P. Raleigh
- Institute of Structural and Molecular Biology, Division of Bioscience, University College London, LondonWC1E 6BT, U.K
- Department of Chemistry, Stony Brook University, 100 Nicolls Rd., Stony Brook, New York11794, United States
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Bioscience, University College London, LondonWC1E 6BT, U.K
- Institute of Structural and Molecular Biology, Birkbeck College, University of London, LondonWC1E 7HX, U.K
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16
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Bhanot JS, Fabijanczuk KC, Abdillahi AM, Chao HC, Pizzala NJ, Londry FA, Dziekonski ET, Hager JW, McLuckey SA. Adaptation and Operation of a Quadrupole/Time-of-Flight Tandem Mass Spectrometer for High Mass Ion/Ion Reaction Studies. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2022; 478:116874. [PMID: 37032994 PMCID: PMC10081487 DOI: 10.1016/j.ijms.2022.116874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
A commercial quadrupole/time-of-flight tandem mass spectrometer has been modified and evaluated for its performance in conducting ion/ion reaction studies involving high mass (>100 kDa) ions. Modifications include enabling the application of dipolar AC waveforms to opposing rods in three quadrupole arrays in the ion path. This modification allows for resonance excitation of ions to effect ion activation, selective ion isolation, and ion parking. The other set of opposing rods in each array is enabled for the application of dipolar DC voltages for the purpose of broad-band (non-selective) ion heating. The plates between each quadrupole array are enabled for the application of either DC or AC (or both) voltages. The use of AC voltages allows for the simultaneous storage of ions of opposite polarity, thereby enabling mutual storage ion/ion reactions. Ions derived from nano-electrospray ionization of GroEL and β-galactosidase under native conditions were used to evaluate limits of instrument performance, in terms of m/z range, ion isolation, and ion storage. After adjustment of the pulser frequency, ions as high in m/z as 400,000 were detected. Significant losses in efficiency were noted above m/z 250,000 that is likely due to roll-over in the ion detector efficiency and possibly also due to limitations in ion transfer efficiency from the collision quadrupole to the pulser region of the mass analyzer. No measurable decrease in the apparent mass resolving power was noted upon charge state reduction of the model ions. Resonance ejection techniques that employ the dipolar AC capabilities of the quadrupoles allow for ion isolation at m/z values much greater than the RF/DC limitation of Q1 of m/z = 2100. For example, at the highest low-mass cutoff achievable in the collision quadrupole (m/z = 500), it is possible to isolate ions of m/z as high as 62,000. This is limited by the lowest dipolar AC frequency (5 kHz) that can be applied. A simple model is included to provide for an estimate of the ion cloud radius based on ion m/z, ion z, and ion trap operating conditions. The model predicts that singly charged ions of 1 MDa and thermal energy can be contained in the ion trap at the maximum low-mass cutoff, although such an ion would not be detected efficiently. Doubly charged GroEL ions were observed experimentally. Collectively, the performance characteristics at high m/z, the functionality provided by the standard instrument capabilities, the modifications described above, and highly flexible instrument control software provide for a highly versatile platform for the study of high mass ion/ion reactions.
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Affiliation(s)
- Jay S. Bhanot
- Department of Chemistry, Purdue University, West Lafayette, IN, USA 47907-2084
| | | | | | - Hsi-Chun Chao
- Department of Chemistry, Purdue University, West Lafayette, IN, USA 47907-2084
| | - Nicolas J. Pizzala
- Department of Chemistry, Purdue University, West Lafayette, IN, USA 47907-2084
| | | | | | | | - Scott A. McLuckey
- Department of Chemistry, Purdue University, West Lafayette, IN, USA 47907-2084
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17
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Dafun AS, Marcoux J. Structural mass spectrometry of membrane proteins. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2022; 1870:140813. [PMID: 35750312 DOI: 10.1016/j.bbapap.2022.140813] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 06/10/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
The analysis of proteins and protein complexes by mass spectrometry (MS) has come a long way since the invention of electrospray ionization (ESI) in the mid 80s. Originally used to characterize small soluble polypeptide chains, MS has progressively evolved over the past 3 decades towards the analysis of samples of ever increasing heterogeneity and complexity, while the instruments have become more and more sensitive and resolutive. The proofs of concepts and first examples of most structural MS methods appeared in the early 90s. However, their application to membrane proteins, key targets in the biopharma industry, is more recent. Nowadays, a wealth of information can be gathered from such MS-based methods, on all aspects of membrane protein structure: sequencing (and more precisely proteoform characterization), but also stoichiometry, non-covalent ligand binding (metals, drug, lipids, carbohydrates), conformations, dynamics and distance restraints for modelling. In this review, we present the concept and some historical and more recent applications on membrane proteins, for the major structural MS methods.
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Affiliation(s)
- Angelique Sanchez Dafun
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Julien Marcoux
- Institut de Pharmacologie et de Biologie Structurale (IPBS), Université de Toulouse, CNRS, UPS, Toulouse, France.
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18
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Liu FC, Ridgeway ME, Park MA, Bleiholder C. Tandem-trapped ion mobility spectrometry/mass spectrometry ( tTIMS/MS): a promising analytical method for investigating heterogenous samples. Analyst 2022; 147:2317-2337. [PMID: 35521797 PMCID: PMC9914546 DOI: 10.1039/d2an00335j] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Ion mobility spectrometry/mass spectrometry (IMS/MS) is widely used to study various levels of protein structure. Here, we review the current state of affairs in tandem-trapped ion mobility spectrometry/mass spectrometry (tTIMS/MS). Two different tTIMS/MS instruments are discussed in detail: the first tTIMS/MS instrument, constructed from coaxially aligning two TIMS devices; and an orthogonal tTIMS/MS configuration that comprises an ion trap for irradiation of ions with UV photons. We discuss the various workflows the two tTIMS/MS setups offer and how these can be used to study primary, tertiary, and quaternary structures of protein systems. We also discuss, from a more fundamental perspective, the processes that lead to denaturation of protein systems in tTIMS/MS and how to soften the measurement so that biologically meaningful structures can be characterised with tTIMS/MS. We emphasize the concepts underlying tTIMS/MS to underscore the opportunities tandem-ion mobility spectrometry methods offer for investigating heterogeneous samples.
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Affiliation(s)
- Fanny C. Liu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306-4390, USA
| | | | | | - Christian Bleiholder
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306-4390, USA. .,Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4390, USA
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19
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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: 38] [Impact Index Per Article: 19.0] [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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20
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Vallejo DD, Ramírez CR, Parson KF, Han Y, Gadkari VG, Ruotolo BT. Mass Spectrometry Methods for Measuring Protein Stability. Chem Rev 2022; 122:7690-7719. [PMID: 35316030 PMCID: PMC9197173 DOI: 10.1021/acs.chemrev.1c00857] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mass spectrometry is a central technology in the life sciences, providing our most comprehensive account of the molecular inventory of the cell. In parallel with developments in mass spectrometry technologies targeting such assessments of cellular composition, mass spectrometry tools have emerged as versatile probes of biomolecular stability. In this review, we cover recent advancements in this branch of mass spectrometry that target proteins, a centrally important class of macromolecules that accounts for most biochemical functions and drug targets. Our efforts cover tools such as hydrogen-deuterium exchange, chemical cross-linking, ion mobility, collision induced unfolding, and other techniques capable of stability assessments on a proteomic scale. In addition, we focus on a range of application areas where mass spectrometry-driven protein stability measurements have made notable impacts, including studies of membrane proteins, heat shock proteins, amyloidogenic proteins, and biotherapeutics. We conclude by briefly discussing the future of this vibrant and fast-moving area of research.
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Affiliation(s)
- Daniel D. Vallejo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Carolina Rojas Ramírez
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Kristine F. Parson
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Yilin Han
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Varun G. Gadkari
- Department of Chemistry, 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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21
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Abstract
Native mass spectrometry (MS) involves the analysis and characterization of macromolecules, predominantly intact proteins and protein complexes, whereby as much as possible the native structural features of the analytes are retained. As such, native MS enables the study of secondary, tertiary, and even quaternary structure of proteins and other biomolecules. Native MS represents a relatively recent addition to the analytical toolbox of mass spectrometry and has over the past decade experienced immense growth, especially in enhancing sensitivity and resolving power but also in ease of use. With the advent of dedicated mass analyzers, sample preparation and separation approaches, targeted fragmentation techniques, and software solutions, the number of practitioners and novel applications has risen in both academia and industry. This review focuses on recent developments, particularly in high-resolution native MS, describing applications in the structural analysis of protein assemblies, proteoform profiling of─among others─biopharmaceuticals and plasma proteins, and quantitative and qualitative analysis of protein-ligand interactions, with the latter covering lipid, drug, and carbohydrate molecules, to name a few.
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Affiliation(s)
- Sem Tamara
- Biomolecular
Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular
Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584
CH Utrecht, The Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Maurits A. den Boer
- Biomolecular
Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular
Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584
CH Utrecht, The Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Albert J. R. Heck
- Biomolecular
Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular
Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584
CH Utrecht, The Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
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22
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Sinz A, Wei AAJ, Iacobucci C, Schultze W, Ihling CH, Arlt C. Different Oligomeric States of the Tumor Suppressor p53 Show Identical Binding Behavior Towards the S100β Homodimer. Chembiochem 2022; 23:e202100665. [PMID: 35333001 PMCID: PMC9400850 DOI: 10.1002/cbic.202100665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 03/01/2022] [Indexed: 12/01/2022]
Abstract
The tumor suppressor protein p53 is a transcription factor that is referred to as the “guardian of the genome” and plays an important role in cancer development. p53 is active as a homotetramer; the S100β homodimer binds to the intrinsically disordered C‐terminus of p53 affecting its transcriptional activity. The p53/S100β complex is regarded as highly promising therapeutic target in cancer. It has been suggested that S100β exerts its oncogenic effects by altering the p53 oligomeric state. Our aim was to study the structures and oligomerization behavior of different p53/S100β complexes by ESI‐MS, XL‐MS, and SPR. Wild‐type p53 and single amino acid variants, representing different oligomeric states of p53 were individually investigated regarding their binding behavior towards S100β. The stoichiometry of the different p53/S100β complexes were determined by ESI‐MS showing that tetrameric, dimeric, and monomeric p53 variants all bind to an S100β dimer. In addition, XL‐MS revealed the topologies of the p53/S100β complexes to be independent of p53’s oligomeric state. With SPR, the thermodynamic parameters were determined for S100β binding to tetrameric, dimeric, or monomeric p53 variants. Our data prove that the S100β homodimer binds to different oligomeric states of p53 with similar binding affinities. This emphasizes the need for alternative explanations to describe the molecular mechanisms underlying p53/S100β interaction.
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Affiliation(s)
- Andrea Sinz
- Martin-Luther-University Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Strasse 4, 6120, Halle, GERMANY
| | - Alan An Jung Wei
- Martin-Luther-Universität Halle-Wittenberg: Martin-Luther-Universitat Halle-Wittenberg, Department of Pharm.Chem. & Bioanalytics, 06120, Halle, GERMANY
| | - Claudio Iacobucci
- Martin-Luther-Universität Halle-Wittenberg: Martin-Luther-Universitat Halle-Wittenberg, Department of Pharm. Chem. & Bioanalytics, 06120, Halle, GERMANY
| | - Wiebke Schultze
- Martin-Luther-Universität Halle-Wittenberg: Martin-Luther-Universitat Halle-Wittenberg, Department of Pharm. Chem. & Bioanalytics, 06120, Halle, GERMANY
| | - Christian H Ihling
- Martin-Luther-Universität Halle-Wittenberg: Martin-Luther-Universitat Halle-Wittenberg, Department of Pharm. Chem. & Bioanalytics, 06120, Halle, GERMANY
| | - Christian Arlt
- Martin-Luther-Universität Halle-Wittenberg: Martin-Luther-Universitat Halle-Wittenberg, Department of Pharm. Chem. & Bioanalytics, 06120, Halle, GERMANY
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23
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Pham KN, Fernandez-Lima F. Structural Characterization of Human Histone H4.1 by Tandem Nonlinear and Linear Ion Mobility Spectrometry Complemented with Molecular Dynamics Simulations. ACS OMEGA 2021; 6:29567-29576. [PMID: 34778628 PMCID: PMC8582071 DOI: 10.1021/acsomega.1c03744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 10/15/2021] [Indexed: 06/13/2023]
Abstract
Extracellular histone H4 is an attractive drug target owing to its roles in organ failure in sepsis and other diseases. To identify inhibitors using in silico methods, information on histone H4 structural dynamics and three-dimensional (3D) structural coordinates is required. Here, DNA-free histone H4 type 1 (H4.1) was characterized by utilizing tandem nonlinear and linear ion mobility spectrometry (FAIMS-TIMS) coupled to mass spectrometry (MS) complemented with molecular dynamics (MD) simulations. The gas-phase structures of H4.1 are dependent on the starting solution conditions, evidenced by differences in charge state distributions, mobility distributions, and collision-induced unfolding (CIU) pathways. The experimental results show that H4.1 adopts diverse conformational types from compact (C) to partially folded (P) and subsequently elongated (E) structures. Molecular dynamics simulations provided candidate structures for the histone H4.1 monomer in solution and for the gas-phase structures observed using FAIMS-IMS-TOF MS as a function of the charge state and mobility distribution. A combination of the FAIMS-TIMS experimental results with theoretical dipole calculations reveals the important role of charge distribution in the dipole alignment of H4.1 elongated structures at high electric fields. A comparison of the secondary and primary structures of DNA-free H2A.1 and H4.1 is made based on the experimental IMS-MS and MD findings.
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Affiliation(s)
- Khoa N. Pham
- Department
of Chemistry and Biochemistry, Florida International
University, Miami, Florida 33199, United States
| | - Francisco Fernandez-Lima
- Department
of Chemistry and Biochemistry, Florida International
University, Miami, Florida 33199, United States
- Biomolecular
Science Institute, Florida International
University, Miami, Florida 33199, United
States
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24
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Britt HM, Cragnolini T, Thalassinos K. Integration of Mass Spectrometry Data for Structural Biology. Chem Rev 2021; 122:7952-7986. [PMID: 34506113 DOI: 10.1021/acs.chemrev.1c00356] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Mass spectrometry (MS) is increasingly being used to probe the structure and dynamics of proteins and the complexes they form with other macromolecules. There are now several specialized MS methods, each with unique sample preparation, data acquisition, and data processing protocols. Collectively, these methods are referred to as structural MS and include cross-linking, hydrogen-deuterium exchange, hydroxyl radical footprinting, native, ion mobility, and top-down MS. Each of these provides a unique type of structural information, ranging from composition and stoichiometry through to residue level proximity and solvent accessibility. Structural MS has proved particularly beneficial in studying protein classes for which analysis by classic structural biology techniques proves challenging such as glycosylated or intrinsically disordered proteins. To capture the structural details for a particular system, especially larger multiprotein complexes, more than one structural MS method with other structural and biophysical techniques is often required. Key to integrating these diverse data are computational strategies and software solutions to facilitate this process. We provide a background to the structural MS methods and briefly summarize other structural methods and how these are combined with MS. We then describe current state of the art approaches for the integration of structural MS data for structural biology. We quantify how often these methods are used together and provide examples where such combinations have been fruitful. To illustrate the power of integrative approaches, we discuss progress in solving the structures of the proteasome and the nuclear pore complex. We also discuss how information from structural MS, particularly pertaining to protein dynamics, is not currently utilized in integrative workflows and how such information can provide a more accurate picture of the systems studied. We conclude by discussing new developments in the MS and computational fields that will further enable in-cell structural studies.
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Affiliation(s)
- Hannah M Britt
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, United Kingdom
| | - Tristan Cragnolini
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, United Kingdom.,Institute of Structural and Molecular Biology, Birkbeck College, University of London, London WC1E 7HX, United Kingdom
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, United Kingdom.,Institute of Structural and Molecular Biology, Birkbeck College, University of London, London WC1E 7HX, United Kingdom
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25
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Bennett JL, Nguyen GTH, Donald WA. Protein-Small Molecule Interactions in Native Mass Spectrometry. Chem Rev 2021; 122:7327-7385. [PMID: 34449207 DOI: 10.1021/acs.chemrev.1c00293] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Small molecule drug discovery has been propelled by the continual development of novel scientific methodologies to occasion therapeutic advances. Although established biophysical methods can be used to obtain information regarding the molecular mechanisms underlying drug action, these approaches are often inefficient, low throughput, and ineffective in the analysis of heterogeneous systems including dynamic oligomeric assemblies and proteins that have undergone extensive post-translational modification. Native mass spectrometry can be used to probe protein-small molecule interactions with unprecedented speed and sensitivity, providing unique insights into polydisperse biomolecular systems that are commonly encountered during the drug discovery process. In this review, we describe potential and proven applications of native MS in the study of interactions between small, drug-like molecules and proteins, including large multiprotein complexes and membrane proteins. Approaches to quantify the thermodynamic and kinetic properties of ligand binding are discussed, alongside a summary of gas-phase ion activation techniques that have been used to interrogate the structure of protein-small molecule complexes. We additionally highlight some of the key areas in modern drug design for which native mass spectrometry has elicited significant advances. Future developments and applications of native mass spectrometry in drug discovery workflows are identified, including potential pathways toward studying protein-small molecule interactions on a whole-proteome scale.
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Affiliation(s)
- Jack L Bennett
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Giang T H Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
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26
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Eldrid C, Ben-Younis A, Ujma J, Britt H, Cragnolini T, Kalfas S, Cooper-Shepherd D, Tomczyk N, Giles K, Morris M, Akter R, Raleigh D, Thalassinos K. Cyclic Ion Mobility-Collision Activation Experiments Elucidate Protein Behavior in the Gas Phase. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1545-1552. [PMID: 34006100 PMCID: PMC8172447 DOI: 10.1021/jasms.1c00018] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Ion mobility coupled to mass spectrometry (IM-MS) is widely used to study protein dynamics and structure in the gas phase. Increasing the energy with which the protein ions are introduced to the IM cell can induce them to unfold, providing information on the comparative energetics of unfolding between different proteoforms. Recently, a high-resolution cyclic IM-mass spectrometer (cIM-MS) was introduced, allowing multiple, consecutive tandem IM experiments (IMn) to be carried out. We describe a tandem IM technique for defining detailed protein unfolding pathways and the dynamics of disordered proteins. The method involves multiple rounds of IM separation and collision activation (CA): IM-CA-IM and CA-IM-CA-IM. Here, we explore its application to studies of a model protein, cytochrome C, and dimeric human islet amyloid polypeptide (hIAPP), a cytotoxic and amyloidogenic peptide involved in type II diabetes. In agreement with prior work using single stage IM-MS, several unfolding events are observed for cytochrome C. IMn-MS experiments also show evidence of interconversion between compact and extended structures. IMn-MS data for hIAPP shows interconversion prior to dissociation, suggesting that the certain conformations have low energy barriers between them and transition between compact and extended forms.
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Affiliation(s)
- Charles Eldrid
- Institute
of Structural and Molecular Biology, Division of Bioscience, University College London, London, WC1E 6BT, U.K.
| | - Aisha Ben-Younis
- Institute
of Structural and Molecular Biology, Division of Bioscience, University College London, London, WC1E 6BT, U.K.
| | - Jakub Ujma
- Waters
Corporation, Wilmslow SK9 4AX, U.K.
| | - Hannah Britt
- Institute
of Structural and Molecular Biology, Division of Bioscience, University College London, London, WC1E 6BT, U.K.
| | - Tristan Cragnolini
- Institute
of Structural and Molecular Biology, Birkbeck College, University of London, London WC1E 7HX, U.K.
| | - Symeon Kalfas
- Institute
of Structural and Molecular Biology, Division of Bioscience, University College London, London, WC1E 6BT, U.K.
| | | | | | | | | | - Rehana Akter
- Department
of Chemistry, Stony Brook University, 100 Nicolls Road, Stony Brook, New York 11794, United States
| | - Daniel Raleigh
- Institute
of Structural and Molecular Biology, Division of Bioscience, University College London, London, WC1E 6BT, U.K.
- Department
of Chemistry, Stony Brook University, 100 Nicolls Road, Stony Brook, New York 11794, United States
| | - Konstantinos Thalassinos
- Institute
of Structural and Molecular Biology, Division of Bioscience, University College London, London, WC1E 6BT, U.K.
- Institute
of Structural and Molecular Biology, Birkbeck College, University of London, London WC1E 7HX, U.K.
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27
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Pham KN, Mamun Y, Fernandez-Lima F. Structural Heterogeneity of Human Histone H2A.1. J Phys Chem B 2021; 125:4977-4986. [PMID: 33974801 PMCID: PMC8568062 DOI: 10.1021/acs.jpcb.1c00335] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Histones are highly basic chromatin proteins that tightly package and order eukaryotic DNA into nucleosomes. While the atomic structure of the nucleosomes has been determined, the three-dimensional structure of DNA-free histones remains unresolved. Here, we combine tandem nonlinear and linear ion mobility spectrometry (FAIMS-TIMS) coupled to mass spectrometry in parallel with molecular modeling to study the conformational space of a DNA-free histone H2A type 1 (H2A.1). Experimental results showed the dependence of the gas-phase structures on the starting solution conditions, characterized by charge state distributions, mobility distributions, and collision-induced-unfolding pathways. The measured H2A.1 gas-phase structures showed a high diversity of structural features ranging from compact (C) to partially folded (P) and then highly elongated (E) conformations. Molecular dynamics simulations provided candidate structures for the solution H2A.1 native conformation with folded N- and C-terminal tails, as well as gas-phase candidate structures associated with the mobility trends. Complementary collision cross section and dipole calculations showed that the charge distribution in the case of elongated gas-phase structures, where basic and acidic residues are mostly exposed (e.g., z > 15+), is sufficient to induce differences in the dipole alignment at high electric fields, in good agreement with the trends observed during the FAIMS-TIMS experiments.
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Affiliation(s)
- Khoa N Pham
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
| | - Yasir Mamun
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
| | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States.,Biomolecular Science Institute, Florida International University, Miami, Florida 33199, United States
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28
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McCabe JW, Hebert MJ, Shirzadeh M, Mallis CS, Denton JK, Walker TE, Russell DH. THE IMS PARADOX: A PERSPECTIVE ON STRUCTURAL ION MOBILITY-MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2021; 40:280-305. [PMID: 32608033 PMCID: PMC7989064 DOI: 10.1002/mas.21642] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/03/2020] [Indexed: 05/06/2023]
Abstract
Studies of large proteins, protein complexes, and membrane protein complexes pose new challenges, most notably the need for increased ion mobility (IM) and mass spectrometry (MS) resolution. This review covers evolutionary developments in IM-MS in the authors' and key collaborators' laboratories with specific focus on developments that enhance the utility of IM-MS for structural analysis. IM-MS measurements are performed on gas phase ions, thus "structural IM-MS" appears paradoxical-do gas phase ions retain their solution phase structure? There is growing evidence to support the notion that solution phase structure(s) can be retained by the gas phase ions. It should not go unnoticed that we use "structures" in this statement because an important feature of IM-MS is the ability to deal with conformationally heterogeneous systems, thus providing a direct measure of conformational entropy. The extension of this work to large proteins and protein complexes has motivated our development of Fourier-transform IM-MS instruments, a strategy first described by Hill and coworkers in 1985 (Anal Chem, 1985, 57, pp. 402-406) that has proved to be a game-changer in our quest to merge drift tube (DT) and ion mobility and the high mass resolution orbitrap MS instruments. DT-IMS is the only method that allows first-principles determinations of rotationally averaged collision cross sections (CSS), which is essential for studies of biomolecules where the conformational diversities of the molecule precludes the use of CCS calibration approaches. The Fourier transform-IM-orbitrap instrument described here also incorporates the full suite of native MS/IM-MS capabilities that are currently employed in the most advanced native MS/IM-MS instruments. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.
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Affiliation(s)
- Jacob W McCabe
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - Michael J Hebert
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - Mehdi Shirzadeh
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | | | - Joanna K Denton
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - Thomas E Walker
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - David H Russell
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
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29
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Konermann L, Aliyari E, Lee JH. Mobile Protons Limit the Stability of Salt Bridges in the Gas Phase: Implications for the Structures of Electrosprayed Protein Ions. J Phys Chem B 2021; 125:3803-3814. [PMID: 33848419 DOI: 10.1021/acs.jpcb.1c00944] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Electrosprayed protein ions can retain native-like conformations. The intramolecular contacts that stabilize these compact gas-phase structures remain poorly understood. Recent work has uncovered abundant salt bridges in electrosprayed proteins. Salt bridges are zwitterionic BH+/A- contacts. The low dielectric constant in the vacuum strengthens electrostatic interactions, suggesting that salt bridges could be a key contributor to the retention of compact protein structures. A problem with this assertion is that H+ are mobile, such that H+ transfer can convert salt bridges into neutral B0/HA0 contacts. This possible salt bridge annihilation puts into question the role of zwitterionic motifs in the gas phase, and it calls for a detailed analysis of BH+/A- versus B0/HA0 interactions. Here, we investigate this issue using molecular dynamics (MD) simulations and electrospray experiments. MD data for short model peptides revealed that salt bridges with static H+ have dissociation energies around 700 kJ mol-1. The corresponding B0/HA0 contacts are 1 order of magnitude weaker. When considering the effects of mobile H+, BH+/A- bond energies were found to be between these two extremes, confirming that H+ migration can significantly weaken salt bridges. Next, we examined the protein ubiquitin under collision-induced unfolding (CIU) conditions. CIU simulations were conducted using three different MD models: (i) Positive-only runs with static H+ did not allow for salt bridge formation and produced highly expanded CIU structures. (ii) Zwitterionic runs with static H+ resulted in abundant salt bridges, culminating in much more compact CIU structures. (iii) Mobile H+ simulations allowed for the dynamic formation/annihilation of salt bridges, generating CIU structures intermediate between scenarios (i) and (ii). Our results uncover that mobile H+ limit the stabilizing effects of salt bridges in the gas phase. Failure to consider the effects of mobile H+ in MD simulations will result in unrealistic outcomes under CIU conditions.
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Affiliation(s)
- Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Elnaz Aliyari
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Justin H Lee
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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30
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Cejkov M, Greer T, Johnson RO, Zheng X, Li N. Electron Transfer Dissociation Parameter Optimization Using Design of Experiments Increases Sequence Coverage of Monoclonal Antibodies. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:762-771. [PMID: 33596068 DOI: 10.1021/jasms.0c00458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Middle-down analysis of monoclonal antibodies (mAbs) by tandem mass spectrometry (MS2) can provide detailed insight into their primary structure with minimal sample preparation. The middle-down approach uses an enzyme to cleave mAbs into Fc/2, LC, and Fd subunits that are then analyzed by reversed phase liquid chromatography tandem mass spectrometry (RPLC-MS2). As maximum sequence coverage is desired to obtain meaningful structural information at the subunit level, a host of dissociation methods have been developed, and sometimes combined, to bolster fragmentation and increase the number of identified fragments. Here, we present a design of experiments (DOE) approach to optimize MS2 parameters, in particular those that may influence electron transfer dissociation (ETD) efficiency to increase the sequence coverage of antibody subunits. Applying this approach to the NIST monoclonal antibody standard (NISTmAb) using three RPLC-MS2 runs resulted in high sequence coverages of 67%, 67%, and 52% for Fc/2, LC, and Fd subunits, respectively. In addition, we apply this DOE strategy to model the parameters required to maximize the number of fragments produced in "low", "medium", and "high" mass ranges, which ultimately resulted in even higher sequence coverages of NISTmAb subunits (75%, 78%, and 64% for Fc/2, LC, and Fd subunits, respectively). The DOE approach provides high sequence coverage percentages utilizing only one fragmentation method, ETD, and could be extended to other state-of-the-art techniques that combine multiple fragmentation mechanisms to increase coverage.
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Affiliation(s)
- Milos Cejkov
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Tyler Greer
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Reid O'Brien Johnson
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Xiaojing Zheng
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Ning Li
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
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31
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Scratching the surface: native mass spectrometry of peripheral membrane protein complexes. Biochem Soc Trans 2021; 48:547-558. [PMID: 32129823 PMCID: PMC7192793 DOI: 10.1042/bst20190787] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 02/09/2020] [Accepted: 02/11/2020] [Indexed: 02/06/2023]
Abstract
A growing number of integral membrane proteins have been shown to tune their activity by selectively interacting with specific lipids. The ability to regulate biological functions via lipid interactions extends to the diverse group of proteins that associate only peripherally with the lipid bilayer. However, the structural basis of these interactions remains challenging to study due to their transient and promiscuous nature. Recently, native mass spectrometry has come into focus as a new tool to investigate lipid interactions in membrane proteins. Here, we outline how the native MS strategies developed for integral membrane proteins can be applied to generate insights into the structure and function of peripheral membrane proteins. Specifically, native MS studies of proteins in complex with detergent-solubilized lipids, bound to lipid nanodiscs, and released from native-like lipid vesicles all shed new light on the role of lipid interactions. The unique ability of native MS to capture and interrogate protein–protein, protein–ligand, and protein–lipid interactions opens exciting new avenues for the study of peripheral membrane protein biology.
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32
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Sever AIM, Yin V, Konermann L. Interrogating the Quaternary Structure of Noncanonical Hemoglobin Complexes by Electrospray Mass Spectrometry and Collision-Induced Dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:270-280. [PMID: 33124417 DOI: 10.1021/jasms.0c00320] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Various activation methods are available for the fragmentation of gaseous protein complexes produced by electrospray ionization (ESI). Such experiments can potentially yield insights into quaternary structure. Collision-induced dissociation (CID) is the most widely used fragmentation technique. Unfortunately, CID of protein complexes is dominated by the ejection of highly charged monomers, a process that does not yield any structural insights. Using hemoglobin (Hb) as a model system, this work examines under what conditions CID generates structurally informative subcomplexes. Native ESI mainly produced tetrameric Hb ions. In addition, "noncanonical" hexameric and octameric complexes were observed. CID of all these species [(αβ)2, (αβ)3, and (αβ)4] predominantly generated highly charged monomers. In addition, we observed hexamer → tetramer + dimer dissociation, implying that hexamers have a tetramer··dimer architecture. Similarly, the observation of octamer → two tetramer dissociation revealed that octamers have a tetramer··tetramer composition. Gas-phase candidate structures of Hb assemblies were produced by molecular dynamics (MD) simulations. Ion mobility spectrometry was used to identify the most likely candidates. Our data reveal that the capability of CID to produce structurally informative subcomplexes depends on the fate of protein-protein interfaces after transfer into the gas phase. Collapse of low affinity interfaces conjoins the corresponding subunits and favors CID via monomer ejection. Structurally informative subcomplexes are formed only if low affinity interfaces do not undergo a major collapse. However, even in these favorable cases CID is still dominated by monomer ejection, requiring careful analysis of the experimental data for the identification of structurally informative subcomplexes.
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Affiliation(s)
- Alexander I M Sever
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Victor Yin
- 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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33
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Harvey SR, VanAernum ZL, Kostelic MM, Marty MT, Wysocki VH. Probing the structure of nanodiscs using surface-induced dissociation mass spectrometry. Chem Commun (Camb) 2020; 56:15651-15654. [PMID: 33355562 PMCID: PMC7943047 DOI: 10.1039/d0cc05531j] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In the study of membrane proteins and antimicrobial peptides, nanodiscs have emerged as a valuable membrane mimetic to solubilze these molecules in a lipid bilayer. We present the structural characterization of nanodiscs using native mass spectrometry and surface-induced dissociation, which are powerful tools in structural biology.
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Affiliation(s)
- Sophie R Harvey
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH, USA.
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34
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Eldrid C, O'Connor E, Thalassinos K. Concentration-dependent coulombic effects in travelling wave ion mobility spectrometry collision cross section calibration. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34 Suppl 4:e8613. [PMID: 31657479 DOI: 10.1002/rcm.8613] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/16/2019] [Accepted: 09/22/2019] [Indexed: 06/10/2023]
Abstract
RATIONALE Travelling wave ion mobility spectrometry (TWIMS) is increasingly being used as a method for calculating the collision cross sections (CCSs) of protein ions. To calculate the CCS values of unknown ions, however, the TWIMS device needs to be calibrated using calibrant proteins of known CCS values. The effect of calibrant protein concentration on the accuracy of the resulting calibration curve has not been explicitly studied so far. We hypothesised that at high protein concentrations the ion density within the TWIMS device will be such that ions will experience space charge effects resulting in deviations, as well as broadening, of ion arrival time distributions (ATDs). Calibration curves using these altered ATDs would therefore result in incorrect CCS values being calculated for the protein ions of interest. METHODS Three protein CCS calibrants, avidin, bovine serum albumin and β-lactgobulin, were prepared at different concentrations and used to calculate the CCS of a non-calibrant protein. Data were collected on a Synapt G1 ion mobility mass spectrometer with a nano-electrospray ionisation (nESI) source using capillaries prepared in house. RESULTS Increasing the concentration of CCS calibrants caused ATD broadening and shifted the ATD peak tops, leading to a significant increase in calculated CCS values. CONCLUSIONS The concentration of protein calibrants can directly affect the quality of the CCS calibration in TWIMS experiments.
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Affiliation(s)
- Charles Eldrid
- Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Eloise O'Connor
- Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck University, Malet Place, London, WC1E 7HX, UK
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35
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Campuzano IDG, Nshanian M, Spahr C, Lantz C, Netirojjanakul C, Li H, Wongkongkathep P, Wolff JJ, Loo JA. High Mass Analysis with a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer: From Inorganic Salt Clusters to Antibody Conjugates and Beyond. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:1155-1162. [PMID: 32196330 PMCID: PMC7261417 DOI: 10.1021/jasms.0c00030] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Analysis of proteins and complexes under native mass spectrometric (MS) and solution conditions was typically performed using time-of-flight (ToF) analyzers, due to their routine high m/z transmission and detection capabilities. However, over recent years, the ability of Orbitrap-based mass spectrometers to transmit and detect a range of high molecular weight species is well documented. Herein, we describe how a 15 Tesla Fourier transform ion cyclotron resonance mass spectrometer (15 T FT-ICR MS) is more than capable of analyzing a wide range of ions in the high m/z scale (>5000), in both positive and negative instrument polarities, ranging from the inorganic cesium iodide salt clusters; a humanized IgG1k monoclonal antibody (mAb; 148.2 kDa); an IgG1-mertansine drug conjugate (148.5 kDa, drug-to-antibody ratio; DAR 2.26); an IgG1-siRNA conjugate (159.1 kDa; ribonucleic acid to antibody ratio; RAR 1); the membrane protein aquaporin-Z (97.2 kDa) liberated from a C8E4 detergent micelle; the empty MSP1D1-nanodisc (142.5 kDa) and the tetradecameric chaperone protein complex GroEL (806.2 kDa; GroEL dimer at 1.6 MDa). We also investigate different regions of the FT-ICR MS that impact ion transmission and desolvation. Finally, we demonstrate how the transmission of these species and resultant spectra are highly consistent with those previously generated on both quadrupole-ToF (Q-ToF) and Orbitrap instrumentation. This report serves as an impactful example of how FT-ICR mass analyzers are competitive to Q-ToFs and Orbitraps for high mass detection at high m/z.
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Affiliation(s)
| | - Michael Nshanian
- Department of Chemistry and Biochemistry, and Department of Biological Chemistry, University of California-Los Angeles, Los Angeles, California 90095, United States
| | - Christopher Spahr
- Amgen Research, Amgen Inc, Thousand Oaks, California 91320, United States
| | - Carter Lantz
- Department of Chemistry and Biochemistry, and Department of Biological Chemistry, University of California-Los Angeles, Los Angeles, California 90095, United States
| | | | - Huilin Li
- Department of Chemistry and Biochemistry, and Department of Biological Chemistry, University of California-Los Angeles, Los Angeles, California 90095, United States
| | - Piriya Wongkongkathep
- Department of Chemistry and Biochemistry, and Department of Biological Chemistry, University of California-Los Angeles, Los Angeles, California 90095, United States
| | - Jeremy J. Wolff
- Bruker Daltonics Inc, Billerica, Massachusetts 01821, United States
| | - Joseph A. Loo
- Department of Chemistry and Biochemistry, and Department of Biological Chemistry, University of California-Los Angeles, Los Angeles, California 90095, United States
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36
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Liu FC, Cropley TC, Ridgeway ME, Park MA, Bleiholder C. Structural Analysis of the Glycoprotein Complex Avidin by Tandem-Trapped Ion Mobility Spectrometry-Mass Spectrometry (Tandem-TIMS/MS). Anal Chem 2020; 92:4459-4467. [PMID: 32083467 DOI: 10.1021/acs.analchem.9b05481] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Glycoproteins play a central role in many biological processes including disease mechanisms. Nevertheless, because glycoproteins are heterogeneous entities, it remains unclear how glycosylation modulates the protein structure and function. Here, we assess the ability of tandem-trapped ion mobility spectrometry-mass spectrometry (tandem-TIMS/MS) to characterize the structure and sequence of the homotetrameric glycoprotein avidin. We show that (1) tandem-TIMS/MS retains native-like avidin tetramers with deeply buried solvent particles; (2) applying high activation voltages in the interface of tandem-TIMS results in collision-induced dissociation (CID) of avidin tetramers into compact monomers, dimers, and trimers with cross sections consistent with X-ray structures and reports from surface-induced dissociation (SID); (3) avidin oligomers are best described as heterogeneous ensembles with (essentially) random combinations of monomer glycoforms; (4) native top-down sequence analysis of the avidin tetramer is possible by CID in tandem-TIMS. Overall, our results demonstrate that tandem-TIMS/MS has the potential to correlate individual proteoforms to variations in protein structure.
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Affiliation(s)
- Fanny C Liu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Tyler C Cropley
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Mark E Ridgeway
- Bruker Daltonics Inc., 40 Manning Road, Billerica, Massachusetts 01821, United States
| | - Melvin A Park
- Bruker Daltonics Inc., 40 Manning Road, Billerica, Massachusetts 01821, United States
| | - Christian Bleiholder
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States.,Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306-4390, United States
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37
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Heidemann J, Kölbel K, Konijnenberg A, Van Dyck J, Garcia-Alai M, Meijers R, Sobott F, Uetrecht C. Further insights from structural mass spectrometry into endocytosis adaptor protein assemblies. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2020; 447:116240. [PMID: 33244295 PMCID: PMC7116418 DOI: 10.1016/j.ijms.2019.116240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
As a fundament in many biologically relevant processes, endocytosis in its different guises has been arousing interest for decades and still does so. This is true for the actual transport and its initiation alike. In clathrin-mediated endocytosis, a comparatively well understood endocytic pathway, a set of adaptor proteins bind specific lipids in the plasma membrane, subsequently assemble and thus form a crucial bridge from clathrin to actin for the ongoing process. These adaptor proteins are highly interesting themselves and the subject of this manuscript. Using many of the instruments that are available now in the mass spectrometry toolbox, we added some facets to the picture of how these minimal assemblies may look, how they form, and what influences the structure. Especially, lipids in the adaptor protein complexes result in reduced charging of a normal sized complex due to their specific binding position. The results further support our structural model of a double ring structure with interfacial lipids.
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Affiliation(s)
- Johannes Heidemann
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251, Hamburg, Germany
| | - Knut Kölbel
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251, Hamburg, Germany
| | - Albert Konijnenberg
- University of Antwerp, Biomolecular & Analytical Mass Spectrometry, Chemistry Dept. Campus Groenenborger V4, Groenenborgerlaan, 171 2020, Antwerp, Belgium
| | - Jeroen Van Dyck
- University of Antwerp, Biomolecular & Analytical Mass Spectrometry, Chemistry Dept. Campus Groenenborger V4, Groenenborgerlaan, 171 2020, Antwerp, Belgium
| | - Maria Garcia-Alai
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation, Notkestrasse 85, 22607, Hamburg, Germany
| | - Rob Meijers
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation, Notkestrasse 85, 22607, Hamburg, Germany
| | - Frank Sobott
- University of Antwerp, Biomolecular & Analytical Mass Spectrometry, Chemistry Dept. Campus Groenenborger V4, Groenenborgerlaan, 171 2020, Antwerp, Belgium
- Astbury Centre for Structural Molecular and Cellular Biology, School of Molecular and Cellular Biology, University of Leeds, LS3 9JT, United Kingdom
| | - Charlotte Uetrecht
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251, Hamburg, Germany
- European XFEL GmbH, Holzkoppel 4, 22869, Schenefeld, Germany
- Corresponding author. Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251, Hamburg, Germany.
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McAlary L, Harrison JA, Aquilina JA, Fitzgerald SP, Kelso C, Benesch JL, Yerbury JJ. Trajectory Taken by Dimeric Cu/Zn Superoxide Dismutase through the Protein Unfolding and Dissociation Landscape Is Modulated by Salt Bridge Formation. Anal Chem 2019; 92:1702-1711. [DOI: 10.1021/acs.analchem.9b01699] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Luke McAlary
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Julian A. Harrison
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - J. Andrew Aquilina
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | | | - Celine Kelso
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Justin L.P. Benesch
- Department of Chemistry, Physical and Theoretical Chemistry Department, University of Oxford, Oxford OX1 3QZ, U.K
| | - Justin J. Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
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39
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Hong S, Bush MF. Collision-Induced Unfolding Is Sensitive to the Polarity of Proteins and Protein Complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:2430-2437. [PMID: 31502225 DOI: 10.1007/s13361-019-02326-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 08/11/2019] [Accepted: 08/16/2019] [Indexed: 06/10/2023]
Abstract
Collision-induced unfolding (CIU) uses ion mobility to probe the structures of ions of proteins and noncovalent complexes as a function of the extent of gas-phase activation prior to analysis. CIU can be sensitive to domain structures, isoform identities, and binding partners, which makes it appealing for many applications. Almost all previous applications of CIU have probed cations. Here, we evaluate the application of CIU to anions and compare the results for anions with those for cations. Towards that end, we developed a "similarity score" that we used to quantify the differences between the results of different CIU experiments and evaluate the significance of those differences relative to the variance of the underlying measurements. Many of the differences between anions and cations that were identified can be attributed to the lower absolute charge states of anions. For example, the extents of the increase in collision cross section over the full range of energies depended strongly on absolute charge state. However, over intermediate energies, there are significant difference between anions and cations with the same absolute charge state. Therefore, CIU is sensitive to the polarity of protein ions. Based on these results, we propose that the utility of CIU to differentiate similar proteins or noncovalent complexes may also depend on polarity. More generally, these results indicate that the relationship between the structures and dynamics of native-like cations and anions deserve further attention and that future studies may benefit from integrating results from ions of both polarities.
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Affiliation(s)
- Seoyeon Hong
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA, 98195-1700, USA
| | - Matthew F Bush
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA, 98195-1700, USA.
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40
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Molecular Organization of Soluble Type III Secretion System Sorting Platform Complexes. J Mol Biol 2019; 431:3787-3803. [DOI: 10.1016/j.jmb.2019.07.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 06/11/2019] [Accepted: 07/01/2019] [Indexed: 12/20/2022]
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41
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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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42
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Eldrid C, Ujma J, Kalfas S, Tomczyk N, Giles K, Morris M, Thalassinos K. Gas Phase Stability of Protein Ions in a Cyclic Ion Mobility Spectrometry Traveling Wave Device. Anal Chem 2019; 91:7554-7561. [PMID: 31117399 PMCID: PMC7006968 DOI: 10.1021/acs.analchem.8b05641] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
Ion
mobility mass spectrometry (IM-MS) allows separation of native
protein ions into “conformational families”. Increasing
the IM resolving power should allow finer structural information to
be obtained and can be achieved by increasing the length of the IM
separator. This, however, increases the time that protein ions spend
in the gas phase and previous experiments have shown that the initial
conformations of small proteins can be lost within tens of milliseconds.
Here, we report on investigations of protein ion stability using a
multipass traveling wave (TW) cyclic IM (cIM) device. Using this device,
minimal structural changes were observed for Cytochrome C after hundreds
of milliseconds, while no changes were observed for a larger multimeric
complex (Concanavalin A). The geometry of the instrument (Q-cIM-ToF)
also enables complex tandem IM experiments to be performed, which
were used to obtain more detailed collision-induced unfolding pathways
for Cytochrome C. The instrument geometry provides unique capabilities
with the potential to expand the field of protein analysis via IM-MS.
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Affiliation(s)
- Charles Eldrid
- Institute of Structural and Molecular Biology, Division of Biosciences , University College London , London , WC1E 6BT , United Kingdom
| | - Jakub Ujma
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Symeon Kalfas
- Institute of Structural and Molecular Biology, Division of Biosciences , University College London , London , WC1E 6BT , United Kingdom
| | - Nick Tomczyk
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Kevin Giles
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Mike Morris
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Biosciences , University College London , London , WC1E 6BT , United Kingdom.,Institute of Structural and Molecular Biology, Birkbeck College , University of London , London , WC1E 7HX , United Kingdom
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43
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Peters I, Metwally H, Konermann L. Mechanism of Electrospray Supercharging for Unfolded Proteins: Solvent-Mediated Stabilization of Protonated Sites During Chain Ejection. Anal Chem 2019; 91:6943-6952. [DOI: 10.1021/acs.analchem.9b01470] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Insa Peters
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Haidy Metwally
- 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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44
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VanAernum ZL, Gilbert JD, Belov ME, Makarov AA, Horning SR, Wysocki VH. Surface-Induced Dissociation of Noncovalent Protein Complexes in an Extended Mass Range Orbitrap Mass Spectrometer. Anal Chem 2019; 91:3611-3618. [PMID: 30688442 PMCID: PMC6516482 DOI: 10.1021/acs.analchem.8b05605] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Native mass spectrometry continues to develop as a significant complement to traditional structural biology techniques. Within native mass spectrometry (MS), surface-induced dissociation (SID) has been shown to be a powerful activation method for the study of noncovalent complexes of biological significance. High-resolution mass spectrometers have become increasingly adapted to the analysis of high-mass ions and have demonstrated their importance in understanding how small mass changes can affect the overall structure of large biomolecular complexes. Herein we demonstrate the first adaptation of surface-induced dissociation in a modified high-mass-range, high-resolution Orbitrap mass spectrometer. The SID device was designed to be installed in the Q Exactive series of Orbitrap mass spectrometers with minimal disruption of standard functions. The performance of the SID-Orbitrap instrument has been demonstrated with several protein complex and ligand-bound protein complex systems ranging from 53 to 336 kDa. We also address the effect of ion source temperature on native protein-ligand complex ions as assessed by SID. Results are consistent with previous findings on quadrupole time-of-flight instruments and suggest that SID coupled to high-resolution MS is well-suited to provide information on the interface interactions within protein complexes and ligand-bound protein complexes.
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45
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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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46
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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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47
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Konermann L, Metwally H, Duez Q, Peters I. Charging and supercharging of proteins for mass spectrometry: recent insights into the mechanisms of electrospray ionization. Analyst 2019; 144:6157-6171. [DOI: 10.1039/c9an01201j] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Molecular dynamics simulations have uncovered mechanistic details of the protein ESI process under various experimental conditions.
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Affiliation(s)
- Lars Konermann
- Department of Chemistry
- The University of Western Ontario
- London
- Canada
| | - Haidy Metwally
- Department of Chemistry
- The University of Western Ontario
- London
- Canada
| | - Quentin Duez
- Department of Chemistry
- The University of Western Ontario
- London
- Canada
| | - Insa Peters
- Department of Chemistry
- The University of Western Ontario
- London
- Canada
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48
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Ben-Nissan G, Vimer S, Tarnavsky M, Sharon M. Structural mass spectrometry approaches to study the 20S proteasome. Methods Enzymol 2019; 619:179-223. [DOI: 10.1016/bs.mie.2018.12.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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49
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Peetz O, Hellwig N, Henrich E, Mezhyrova J, Dötsch V, Bernhard F, Morgner N. LILBID and nESI: Different Native Mass Spectrometry Techniques as Tools in Structural Biology. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:181-191. [PMID: 30225732 PMCID: PMC6318263 DOI: 10.1007/s13361-018-2061-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 08/02/2018] [Accepted: 08/08/2018] [Indexed: 06/08/2023]
Abstract
Native mass spectrometry is applied for the investigation of proteins and protein complexes worldwide. The challenge in native mass spectrometry is maintaining the features of the proteins of interest, such as oligomeric state, bound ligands, or the conformation of the protein complex, during transfer from solution to gas phase. This is an essential prerequisite to allow conclusions about the solution state protein complex, based on the gas phase measurements. Therefore, soft ionization techniques are required. Widely used for the analysis of protein complexes are nanoelectro spray ionization (nESI) mass spectrometers. A newer ionization method is laser induced liquid bead ion desorption (LILBID), which is based on the release of protein complexes from solution phase via infrared (IR) laser desorption. We use both methods in our lab, depending on the requirements of the biological system we are interested in. Here we benchmark the performance of our LILBID mass spectrometer in comparison to a nESI instrument, regarding sample conditions, buffer and additive tolerances, dissociation mechanism and applicability towards soluble and membrane protein complexes. Graphical Abstract ᅟ.
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Affiliation(s)
- Oliver Peetz
- Institute of Physical and Theoretical Chemistry, J.W. Goethe-University, Frankfurt am Main, Germany
| | - Nils Hellwig
- Institute of Physical and Theoretical Chemistry, J.W. Goethe-University, Frankfurt am Main, Germany
| | - Erik Henrich
- Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance, J.W. Goethe-University, Frankfurt am Main, Germany
| | - Julija Mezhyrova
- Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance, J.W. Goethe-University, Frankfurt am Main, Germany
| | - Volker Dötsch
- Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance, J.W. Goethe-University, Frankfurt am Main, Germany
| | - Frank Bernhard
- Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance, J.W. Goethe-University, Frankfurt am Main, Germany
| | - Nina Morgner
- Institute of Physical and Theoretical Chemistry, J.W. Goethe-University, Frankfurt am Main, Germany.
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50
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Ahdash Z, Lau AM, Martens C, Politis A. Analyzing Protein Architectures and Protein-Ligand Complexes by Integrative Structural Mass Spectrometry. J Vis Exp 2018. [PMID: 30371663 PMCID: PMC6235531 DOI: 10.3791/57966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Proteins are an important class of biological macromolecules that play many key roles in cellular functions including gene expression, catalyzing metabolic reactions, DNA repair and replication. Therefore, a detailed understanding of these processes provides critical information on how cells function. Integrative structural MS methods offer structural and dynamical information on protein complex assembly, complex connectivity, subunit stoichiometry, protein oligomerization and ligand binding. Recent advances in integrative structural MS have allowed for the characterization of challenging biological systems including large DNA binding proteins and membrane proteins. This protocol describes how to integrate diverse MS data such as native MS and ion mobility-mass spectrometry (IM-MS) with molecular dynamics simulations to gain insights into a helicase-nuclease DNA repair protein complex. The resulting approach provides a framework for detailed studies of ligand binding to other protein complexes involved in important biological processes.
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Affiliation(s)
| | - Andy M Lau
- Department of Chemistry, King's College London
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