1
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Duez Q, Hoyas S, Josse T, Cornil J, Gerbaux P, De Winter J. Gas-phase structure of polymer ions: Tying together theoretical approaches and ion mobility spectrometry. MASS SPECTROMETRY REVIEWS 2023; 42:1129-1151. [PMID: 34747528 DOI: 10.1002/mas.21745] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 08/17/2021] [Accepted: 08/23/2021] [Indexed: 06/07/2023]
Abstract
An increasing number of studies take advantage of ion mobility spectrometry (IMS) coupled to mass spectrometry (IMS-MS) to investigate the spatial structure of gaseous ions. Synthetic polymers occupy a unique place in the field of IMS-MS. Indeed, due to their intrinsic dispersity, they offer a broad range of homologous ions with different lengths. To help rationalize experimental data, various theoretical approaches have been described. First, the study of trend lines is proposed to derive physicochemical and structural parameters. However, the evaluation of data fitting reflects the overall behavior of the ions without reflecting specific information on their conformation. Atomistic simulations constitute another approach that provide accurate information about the ion shape. The overall scope of this review is dedicated to the synergy between IMS-MS and theoretical approaches, including computational chemistry, demonstrating the essential role they play to fully understand/interpret IMS-MS data.
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Affiliation(s)
- Quentin Duez
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | - Sébastien Hoyas
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | | | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | - Pascal Gerbaux
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
| | - Julien De Winter
- Organic Synthesis and Mass Spectrometry Laboratory, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, Mons, Belgium
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2
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Haidar Y, Konermann L. Effects of Hydrogen/Deuterium Exchange on Protein Stability in Solution and in the Gas Phase. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023. [PMID: 37314114 DOI: 10.1021/jasms.3c00130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Mass spectrometry (MS)-based techniques are widely used for probing protein structure and dynamics in solution. H/D exchange (HDX)-MS is one of the most common approaches in this context. HDX is often considered to be a "benign" labeling method, in that it does not perturb protein behavior in solution. However, several studies have reported that D2O pushes unfolding equilibria toward the native state. The origin, and even the existence of this protein stabilization remain controversial. Here we conducted thermal unfolding assays in solution to confirm that deuterated proteins in D2O are more stable, with 2-4 K higher melting temperatures than unlabeled proteins in H2O. Previous studies tentatively attributed this phenomenon to strengthened H-bonds after deuteration, an effect that may arise from the lower zero-point vibrational energy of the deuterated species. Specifically, it was proposed that strengthened water-water bonds (W···W) in D2O lower the solubility of nonpolar side chains. The current work takes a broader view by noting that protein stability in solution also depends on water-protein (W···P) and protein-protein (P···P) H-bonds. To help unravel these contributions, we performed collision-induced unfolding (CIU) experiments on gaseous proteins generated by native electrospray ionization. CIU profiles of deuterated and unlabeled proteins were indistinguishable, implying that P···P contacts are insensitive to deuteration. Thus, protein stabilization in D2O is attributable to solvent effects, rather than alterations of intraprotein H-bonds. Strengthening of W···W contacts represents one possible explanation, but the stabilizing effect of D2O can also originate from weakened W···P bonds. Future work will be required to elucidate which of these two scenarios is correct, or if both contribute to protein stabilization in D2O. In any case, the often-repeated adage that "D-bonds are more stable than H-bonds" does not apply to intramolecular contacts in native proteins.
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Affiliation(s)
- Yousef Haidar
- 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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3
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Shestoperova EI, Ivanov DG, Strieter ER. Quantitative Analysis of Diubiquitin Isomers Using Ion Mobility Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:931-938. [PMID: 37014729 DOI: 10.1021/jasms.3c00016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The diversity of ubiquitin modifications calls for methods to better characterize ubiquitin chain linkage, length, and morphology. Here, we use multiple linear regression analysis coupled with ion mobility mass spectrometry (IM-MS) to quantify the relative abundance of different ubiquitin dimer isomers. We demonstrate the utility and robustness of this approach by quantifying the relative abundance of different ubiquitin dimers in complex mixtures and comparing the results to the standard, bottom-up ubiquitin AQUA method. Our results provide a foundation for using multiple linear regression analysis and IM-MS to characterize more complex ubiquitin chain architectures.
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Affiliation(s)
- Elizaveta I Shestoperova
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Daniil G Ivanov
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Eric R Strieter
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Molecular & Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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4
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Apo-metallothionein-3 cooperatively forms tightly compact structures under physiological conditions. J Biol Chem 2023; 299:102899. [PMID: 36639030 PMCID: PMC9930159 DOI: 10.1016/j.jbc.2023.102899] [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: 10/20/2022] [Revised: 01/03/2023] [Accepted: 01/06/2023] [Indexed: 01/12/2023] Open
Abstract
Metallothioneins (MTs) are essential mammalian metal chaperones. MT isoform 1 (MT1) is expressed in the kidneys and isoform 3 (MT3) is expressed in nervous tissue. For MTs, the solution-based NMR structure was determined for metal-bound MT1 and MT2, and only one X-ray diffraction structure on a crystallized mixed metal-bound MT2 has been reported. The structure of solution-based metalated MT3 is partially known using NMR methods; however, little is known about the fluxional de novo apo-MT3 because the structure cannot be determined by traditional methods. Here, we used cysteine modification coupled with electrospray ionization mass spectrometry, denaturing reactions with guanidinium chloride, stopped-flow methods measuring cysteine modification and metalation, and ion mobility mass spectrometry to reveal that apo-MT3 adopts a compact structure under physiological conditions and an extended structure under denaturing conditions, with no intermediates. Compared with apo-MT1, we found that this compact apo-MT3 binds to a cysteine modifier more cooperatively at equilibrium and 0.5 times the rate, providing quantitative evidence that many of the 20 cysteines of apo-MT3 are less accessible than those of apo-MT1. In addition, this compact apo-MT3 can be identified as a distinct population using ion mobility mass spectrometry. Furthermore, proposed structural models can be calculated using molecular dynamics methods. Collectively, these findings provide support for MT3 acting as a noninducible regulator of the nervous system compared with MT1 as an inducible scavenger of trace metals and toxic metals in the kidneys.
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5
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Edwards AN, Tran HM, Gallagher ES. Propagating Error through Traveling-Wave Ion Mobility Calibration. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:2621-2630. [PMID: 34662111 DOI: 10.1021/jasms.1c00144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Native mass spectrometry (MS) is used to elucidate the stoichiometry of protein complexes and quantify binding interactions by maintaining native-like, noncovalent interactions in the gas phase. However, ionization forces proteins into specific conformations, losing the solution-phase dynamics associated with solvated protein structures. Comparison of gas-phase structures to those in solution, or to other gas-phase ion populations, has many biological implications. For one, analyzing the variety of conformations that are maintained in the gas-phase can provide insight into a protein's solution-phase energy landscape. The gas-phase conformations of proteins and complexes can be investigated using ion mobility (IM) spectrometry. Specifically, drift tube (DT)-IM utilizes uniform electric fields to propel a population of gas-phase ions through a region containing a neutral gas. By measuring the mobility (K) of gas-phase ions, users are able to calculate an average momentum transfer cross section (DTCCS), which provides structural information on the ion. Conversely, in traveling-wave ion mobility spectrometry (TWIMS), TWCCS values cannot be derived directly from an ion's mobility but must be determined following calibration. Though the required calibration adds uncertainty, it is common to report only an average and standard deviation of the calculated TWCCS, accounting for uncertainty associated with replicate measurements, which is a fraction of the overall uncertainty. Herein, we calibrate a TWIMS instrument and derive TWCCSN2 and TWCCSN2→He values for four proteins: cytochrome c, ubiquitin, apo-myoglobin, and holo-myoglobin. We show that compared to reporting only the standard deviation of TWCCS, propagating error through the calibration results in a significant increase in the number of calculated TWCCS values that agree within experimental error with literature values (DTCCS). Incorporating this additional uncertainty provides a more thorough assessment of a protein ion's gas-phase conformations, enabling the structures sampled by native IM-MS to be compared against other reported structures, both experimental and computational.
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Affiliation(s)
- Alexis N Edwards
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Hien M Tran
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
| | - Elyssia S Gallagher
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798, United States
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6
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Aliyari E, Konermann L. Atomistic Insights into the Formation of Nonspecific Protein Complexes during Electrospray Ionization. Anal Chem 2021; 93:12748-12757. [PMID: 34494821 DOI: 10.1021/acs.analchem.1c02836] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Native electrospray ionization (ESI)-mass spectrometry (MS) is widely used for the detection and characterization of multi-protein complexes. A well-known problem with this approach is the possible occurrence of nonspecific protein clustering in the ESI plume. This effect can distort the results of binding affinity measurements, and it can even generate gas-phase complexes from proteins that are strictly monomeric in bulk solution. By combining experiments and molecular dynamics (MD) simulations, the current work for the first time provides detailed insights into the ESI clustering of proteins. Using ubiquitin as a model system, we demonstrate how the entrapment of more than one protein molecule in an ESI droplet can generate nonspecific clusters (e.g., dimers or trimers) via solvent evaporation to dryness. These events are in line with earlier proposals, according to which protein clustering is associated with the charged residue model (CRM). MD simulations on cytochrome c (which carries a large intrinsic positive charge) confirmed the viability of this CRM avenue. In addition, the cytochrome c data uncovered an alternative mechanism where protein-protein contacts were formed early within ESI droplets, followed by cluster ejection from the droplet surface. This second pathway is consistent with the ion evaporation model (IEM). The observation of these IEM events for large protein clusters is unexpected because the IEM has been thought to be associated primarily with low-molecular-weight analytes. In all cases, our MD simulations produced protein clusters that were stabilized by intermolecular salt bridges. The MD-generated charge states agreed with experiments. Overall, this work reveals that ESI-induced protein clustering does not follow a tightly orchestrated pathway but can proceed along different avenues.
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Affiliation(s)
- Elnaz Aliyari
- 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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7
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Cheung See Kit M, Shepherd SO, Prell JS, Webb IK. Experimental Determination of Activation Energies for Covalent Bond Formation via Ion/Ion Reactions and Competing Processes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:2313-2321. [PMID: 33730481 PMCID: PMC9248411 DOI: 10.1021/jasms.1c00025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The combination of ion/ion chemistry with commercially available ion mobility/mass spectrometry systems has allowed rich structural information to be obtained for gaseous protein ions. Recently, the simple modification of such an instrument with an electrospray reagent source has allowed three-dimensional gas-phase interrogation of protein structures through covalent and noncovalent interactions coupled with collision cross section measurements. However, the energetics of these processes have not yet been studied quantitatively. In this work, previously developed Monte Carlo simulations of ion temperatures inside traveling wave ion guides are used to characterize the energetics of the transition state of activated ubiquitin cation/sulfo-benzoyl-HOAt reagent anion long-lived complexes formed via ion/ion reactions. The ΔH‡ and ΔS‡ of major processes observed from collisional activation of long-lived gas-phase ion/ion complexes, namely collision induced unfolding (CIU), covalent bond formation, or neutral loss of the anionic reagent via intramolecular proton transfer, were determined. Covalent bond formation via ion/ion complexes was found to be significantly lower energy compared to unfolding and bond cleavage. The ΔG‡ values of activation of all three processes lie between 55 and 75 kJ/mol, easily accessible with moderate collisional activation. Bond formation is favored over reagent loss at lower activation energies, whereas reagent loss becomes competitive at higher collision energies. Though the ΔG‡ values between CIU of a precursor ion and covalent bond formation of its ion/ion product complex are comparable, our data suggest covalent bond formation does not require extensive isomerization.
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Affiliation(s)
- Melanie Cheung See Kit
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, USA
| | - Samantha O. Shepherd
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, USA
| | - James S. Prell
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, USA
- Materials Science Institute, University of Oregon, Eugene, OR 97403, USA
| | - Ian K. Webb
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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8
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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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9
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Sutton JM, El Zahar NM, Bartlett MG. Oligonucleotide Anion Adduct Formation Using Negative Ion Electrospray Ion-Mobility Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:497-508. [PMID: 33476148 DOI: 10.1021/jasms.0c00380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Improving the mobile phase of electrospray oligonucleotides has been a major focus in the field of oligonucleotides. These improved mobile phases should reduce the charge state envelope of oligonucleotides coupled with electrospray ionization, which is key to reducing spectral complexity and increasing sensitivity. Traditional mobile phase compositions with fluorinated alcohol and alkylamine, like hexafluoroisopropanol (HFIP) and triethylamine (TEA), have a large amount of cationic adduction and many charge states. Utilizing different fluorinated alcohol and alkylamine combinations, like nonafluoro-tert-butyl alcohol (NFTB) and octylamine (OA), can selectively reduce the charge states analyzed. Other classes of biomolecules have been analyzed with anionic salts to stabilize complexes, increase the molecular peak detection, and even provide unique structural information about these molecules; however, there have been no studies using anionic salts with oligonucleotides. Our experiments systematically study the stability and binding of ammonium anionic salt. We show that anions selectively bind low charge states of these oligonucleotides. Ion-mobility measurements are made to determine the collision cross section (CCS) of these oligonucleotides with anion adduction. We utilize both a nucleic acid exact hard sphere simulation (EHSS) calibration and a protein calibration. We are able to show that NFTB/OA is a good choice for the study of oligonucleotides with reduced charge states for the binding of anionic salts and the determination of CCS using ion mobility.
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Affiliation(s)
- J Michael Sutton
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 West Green Street, Athens, Georgia 30602-2352, United States
| | - Noha M El Zahar
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 West Green Street, Athens, Georgia 30602-2352, United States
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Ain Shams University, Organization of African Unity Street, Abassia, Cairo 11566, Egypt
- Medicinal Chemistry Department, Faculty of Pharmacy, King Salman International University, Ras-Sedr, South Sinai Governorate 46612, Egypt
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 West Green Street, Athens, Georgia 30602-2352, United States
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10
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Tran TT, Pan F, Tran L, Roland C, Sagui C. The F19W mutation reduces the binding affinity of the transmembrane Aβ 11-40 trimer to the membrane bilayer. RSC Adv 2021; 11:2664-2676. [PMID: 35424222 PMCID: PMC8693879 DOI: 10.1039/d0ra08837d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/28/2020] [Indexed: 12/23/2022] Open
Abstract
Alzheimer's disease is linked to the aggregation of the amyloid-β protein (Aβ) of 40 or 42 amino acids. Lipid membranes are known to modulate the rate and mechanisms of the Aβ aggregation. Point mutations in Aβ can alter these rates and mechanisms. In particular, experiments show that F19 mutations influence the aggregation rate, but maintain the fibril structures. Here, we used molecular dynamics simulations to examine the effect of the F19W mutation in the 3Aβ11-40 trimer immersed in DPPC lipid bilayers submerged in aqueous solution. Substituting Phe by its closest (non-polar) aromatic amino acid Trp has a dramatic reduction in binding affinity to the phospholipid membrane (measured with respect to the solvated protein) compared to the wild type: the binding free energy of the protein-DPPC lipid bilayer increases by 40-50 kcal mol-1 over the wild-type. This is accompanied by conformational changes and loss of salt bridges, as well as a more complex free energy surface, all indicative of a more flexible and less stable mutated trimer. These results suggest that the impact of mutations can be assessed, at least partially, by evaluating the interaction of the mutated peptides with the lipid membranes.
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Affiliation(s)
- Thanh Thuy Tran
- Laboratory of Theoretical and Computational Biophysics, Ton Duc Thang University Ho Chi Minh City Vietnam
- Faculty of Applied Sciences, Ton Duc Thang University Ho Chi Minh City Vietnam
| | - Feng Pan
- Department of Statistics, Florida State University Tallahassee Florida USA
| | - Linh Tran
- Institute of Fundamental and Applied Sciences, Duy Tan University Ho Chi Minh City 700000 Vietnam
- Faculty of Natural Sciences, Duy Tan University Da Nang City 550000 Vietnam
| | - Christopher Roland
- Department of Physics, North Carolina State University Raleigh North Carolina USA
| | - Celeste Sagui
- Department of Physics, North Carolina State University Raleigh North Carolina USA
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11
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Yin V, Konermann L. Probing the Effects of Heterogeneous Oxidative Modifications on the Stability of Cytochrome c in Solution and in the Gas Phase. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:73-83. [PMID: 32401029 DOI: 10.1021/jasms.0c00089] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Covalent modifications by reactive oxygen species can modulate the function and stability of proteins. Thermal unfolding experiments in solution are a standard tool for probing oxidation-induced stability changes. Complementary to such solution investigations, the stability of electrosprayed protein ions can be assessed in the gas phase by collision-induced unfolding (CIU) and ion-mobility spectrometry. A question that remains to be explored is whether oxidation-induced stability alterations in solution are mirrored by the CIU behavior of gaseous protein ions. Here, we address this question using chloramine-T-oxidized cytochrome c (CT-cyt c) as a model system. CT-cyt c comprises various proteoforms that have undergone MetO formation (+16 Da) and Lys carbonylation (LysCH2-NH2 → LysCHO, -1 Da). We found that CT-cyt c in solution was destabilized, with a ∼5 °C reduced melting temperature compared to unmodified controls. Surprisingly, CIU experiments revealed the opposite trend, i.e., a stabilization of CT-cyt c in the gas phase. To pinpoint the source of this effect, we performed proteoform-resolved CIU on CT-cyt c fractions that had been separated by cation exchange chromatography. In this way, it was possible to identify MetO formation at residue 80 as the key modification responsible for stabilization in the gas phase. Possibly, this effect is caused by newly formed contacts of the sulfoxide with aromatic residues in the protein core. Overall, our results demonstrate that oxidative modifications can affect protein stability in solution and in the gas phase very differently.
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Affiliation(s)
- 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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12
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Aliyari E, Konermann L. Formation of Gaseous Proteins via the Ion Evaporation Model (IEM) in Electrospray Mass Spectrometry. Anal Chem 2020; 92:10807-10814. [DOI: 10.1021/acs.analchem.0c02290] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Elnaz Aliyari
- 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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13
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Wang K, Qiu R, Zhang X, Gillig KJ, Sun W. U-Shaped Mobility Analyzer: A Compact and High-Resolution Counter-Flow Ion Mobility Spectrometer. Anal Chem 2020; 92:8356-8363. [DOI: 10.1021/acs.analchem.0c00868] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Keke Wang
- Shimadzu Research Laboratory (Shanghai) Co. Ltd., Shanghai 201206, People’s Republic of China
| | - Ran Qiu
- Shimadzu Research Laboratory (Shanghai) Co. Ltd., Shanghai 201206, People’s Republic of China
| | - Xiaoqiang Zhang
- Shimadzu Research Laboratory (Shanghai) Co. Ltd., Shanghai 201206, People’s Republic of China
| | - Kent J. Gillig
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Wenjian Sun
- Shimadzu Research Laboratory (Shanghai) Co. Ltd., Shanghai 201206, People’s Republic of China
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14
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Carvalho VV, Cheung See Kit M, Webb IK. Ion Mobility and Gas-Phase Covalent Labeling Study of the Structure and Reactivity of Gaseous Ubiquitin Ions Electrosprayed from Aqueous and Denaturing Solutions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:1037-1046. [PMID: 32255627 PMCID: PMC7205579 DOI: 10.1021/jasms.9b00138] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Gas-phase ion/ion chemistry was coupled to ion mobility/mass spectrometry analysis to correlate the structure of gaseous ubiquitin to its solution structures with selective covalent structural probes. Collision cross section (CCS) distributions were measured to ensure the ubiquitin ions were not unfolded when they were introduced to the gas phase. Aqueous solutions stabilizing the native state of ubiquitin yielded folded ubiquitin structures with CCS values consistent with previously published literature. Denaturing solutions favored several families of unfolded conformations for most of the charge states evaluated. Gas-phase covalent labeling via ion/ion reactions was followed by collision-induced dissociation of the intact, labeled protein to determine which residues were labeled. Ubiquitin 5+ and 6+ electrosprayed from aqueous conditions were covalently modified preferentially at the lysine 29 and arginine 54 positions, indicating that elements of three-dimensional structure were maintained in the gas phase. On the other hand, most ubiquitin ions produced in denaturing conditions were labeled at various other lysine residues, likely due to the availability of additional sites following methanol- and low-pH-induced unfolding. These data support the conservation of ubiquitin structural elements in the gas phase. The research presented here provides the basis for residue-specific characterization of biomolecules in the gas phase.
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Affiliation(s)
| | | | - Ian K. Webb
- Indiana University Purdue University Indianapolis, Indianapolis, IN, USA 46202
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15
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Haler JRN, Massonnet P, Far J, Upert G, Gilles N, Mourier G, Quinton L, De Pauw E. Can IM-MS Collision Cross Sections of Biomolecules Be Rationalized Using Collision Cross-Section Trends of Polydisperse Synthetic Homopolymers? JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:990-995. [PMID: 32233380 DOI: 10.1021/jasms.9b00106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In the past, we developed a method inferring physicochemical properties from ion mobility mass spectrometry (IM-MS) data from polydisperse synthetic homopolymers. We extend here the method to biomolecules that are generally monodisperse. Similarities in the IM-MS behavior were illustrated on proteins and peptides. This allows one to identify ionic species for which intramolecular interactions lead to specific structures.
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Affiliation(s)
- Jean R N Haler
- Mass Spectrometry Laboratory, University of Liège, MolSys Research unit, Quartier Agora, Allée du Six Aout 11, B-4000 Liège, Belgium
| | - Philippe Massonnet
- Mass Spectrometry Laboratory, University of Liège, MolSys Research unit, Quartier Agora, Allée du Six Aout 11, B-4000 Liège, Belgium
- Maastricht Multimodal Molecular Imaging (M4I) Institute, Division of Imaging Mass Spectrometry, 6211 LK Maastricht, The Netherlands
| | - Johann Far
- Mass Spectrometry Laboratory, University of Liège, MolSys Research unit, Quartier Agora, Allée du Six Aout 11, B-4000 Liège, Belgium
| | - Gregory Upert
- Commissariat à l'Energie Atomique CEA, DRF/SIMOPRO, 91191 Gif sur Yvette, France
| | - Nicolas Gilles
- Commissariat à l'Energie Atomique CEA, DRF/SIMOPRO, 91191 Gif sur Yvette, France
| | - Gilles Mourier
- Commissariat à l'Energie Atomique CEA, DRF/SIMOPRO, 91191 Gif sur Yvette, France
| | - Loïc Quinton
- Mass Spectrometry Laboratory, University of Liège, MolSys Research unit, Quartier Agora, Allée du Six Aout 11, B-4000 Liège, Belgium
| | - Edwin De Pauw
- Mass Spectrometry Laboratory, University of Liège, MolSys Research unit, Quartier Agora, Allée du Six Aout 11, B-4000 Liège, Belgium
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16
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Halgand F, Houée-Lévin C, Weik M, Madern D. Remote oxidative modifications induced by oxygen free radicals modify T/R allosteric equilibrium of a hyperthermophilic lactate dehydrogenase. J Struct Biol 2020; 210:107478. [PMID: 32087239 DOI: 10.1016/j.jsb.2020.107478] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/06/2020] [Accepted: 02/13/2020] [Indexed: 12/01/2022]
Abstract
L-Lactate dehydrogenase (LDH) is a model protein allowing to shed light on the fundamental molecular mechanisms that drive the acquisition, evolution and regulation of enzyme properties. In this study, we test the hypothesis of a link between thermal stability of LDHs and their capacity against unfolding induced by reactive oxygen species (ROS) generated by γ-rays irradiation. By using circular dichroism spectroscopy, we analysed that high thermal stability of a thermophilic LDH favours strong resistance against ROS-induced unfolding, in contrast to its psychrophilic and mesophilic counterparts that are less resistant. We suggest that a protein's phenotype linking strong thermal stability and resistance against ROS damages would have been a selective evolutionary advantage. We also find that the enzymatic activity of the thermophilic LDH that is strongly resistant against ROS-unfolding is very sensitive to inactivation by irradiation. To address this counter-intuitive observation, we combined mass spectrometry analyses and enzymatic activity measurements. We demonstrate that the dramatic change on LDH activity was linked to remote chemical modifications away from the active site, that change the equilibrium between low-affinity tense (T-inactive) and high-affinity relaxed (R-active) forms. We found the T-inactive thermophilic enzyme obtained after irradiation can recover its LDH activity by addition of the allosteric effector 1, 6 fructose bis phosphate. We analyse our data within the general framework of allosteric regulation, which requires that an enzyme in solution populates a large diversity of dynamically-interchanging conformations. Our work demonstrates that the radiation-induced inactivation of an enzyme is controlled by its dynamical properties.
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Affiliation(s)
- Frédéric Halgand
- Université Paris Sud-CNRS, UMR 8000, bâtiments 201 P2 and 350, 91405 Orsay, France
| | - Chantal Houée-Lévin
- Université Paris Sud-CNRS, UMR 8000, bâtiments 201 P2 and 350, 91405 Orsay, France
| | - Martin Weik
- Univ. Grenoble Alpes, CEA, CNRS, IBS, 38000 Grenoble, France
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17
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France AP, Migas LG, Sinclair E, Bellina B, Barran PE. Using Collision Cross Section Distributions to Assess the Distribution of Collision Cross Section Values. Anal Chem 2020; 92:4340-4348. [DOI: 10.1021/acs.analchem.9b05130] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Aidan P. France
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology and Photon Science Institute, University of Manchester, 131 Princess Street, Manchester, M1 7DN, U.K
| | - Lukasz G. Migas
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology and Photon Science Institute, University of Manchester, 131 Princess Street, Manchester, M1 7DN, U.K
| | - Eleanor Sinclair
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology and Photon Science Institute, University of Manchester, 131 Princess Street, Manchester, M1 7DN, U.K
| | - Bruno Bellina
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology and Photon Science Institute, University of Manchester, 131 Princess Street, Manchester, M1 7DN, U.K
| | - Perdita E. Barran
- Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology and Photon Science Institute, University of Manchester, 131 Princess Street, Manchester, M1 7DN, U.K
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18
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Martin LM, Konermann L. Enhancing Protein Electrospray Charge States by Multivalent Metal Ions: Mechanistic Insights from MD Simulations and Mass Spectrometry Experiments. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:25-33. [PMID: 32881517 DOI: 10.1021/jasms.9b00027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The structure and reactivity of electrosprayed protein ions is governed by their net charge. Native proteins in non-denaturing aqueous solutions produce low charge states. More highly charged ions are formed when electrospraying proteins that are unfolded and/or exposed to organic supercharging agents. Numerous studies have explored the electrospray process under these various conditions. One phenomenon that has received surprisingly little attention is the charge enhancement caused by multivalent metal ions such as La3+ when electrospraying proteins out of non-denaturing solutions. Here, we conducted mass spectrometry and ion mobility spectrometry experiments, in combination with molecular dynamics (MD) simulations, to uncover the mechanistic basis of this charge enhancement. MD simulations of aqueous ESI droplets reproduced the experimental observation that La3+ boosts protein charge states relative to monovalent metals (e.g., Na+). The simulations showed that gaseous proteins were released by solvent evaporation to dryness, consistent with the charged residue model. Metal ion ejection kept the shrinking droplets close to the Rayleigh limit until ∼99% of the solvent had left. For droplets charged with Na+, metal adduction during the final stage of solvent evaporation produced low protein charge states. Droplets containing La3+ showed a very different behavior. The trivalent nature of La3+ favored adduction to the protein at a very early stage, when most of the solvent had not evaporated yet. This irreversible binding via multidentate contacts suppressed La3+ ejection from the vanishing droplets, such that the resulting gaseous proteins carried significantly more charge. Our results illustrate that MD simulations are suitable for uncovering intricate aspects of electrospray mechanisms, paving the way toward an atomistic understanding of mass spectrometry based analytical workflows.
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Affiliation(s)
- Leanne M Martin
- 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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19
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Marcinko TM, Liang C, Savinov S, Chen J, Vachet RW. Structural Heterogeneity in the Preamyloid Oligomers of β-2-Microglobulin. J Mol Biol 2019; 432:396-409. [PMID: 31711963 DOI: 10.1016/j.jmb.2019.10.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/25/2019] [Accepted: 10/30/2019] [Indexed: 11/29/2022]
Abstract
In dialysis patients, the protein β2-microglobulin (β2m) forms amyloid fibrils in a condition known as dialysis-related amyloidosis. To understand the early stages of the amyloid assembly process, we have used native electrospray ionization (ESI) together with ion mobility mass spectrometry (IM-MS) to study soluble preamyloid oligomers. ESI-IM-MS reveals the presence of multiple conformers for the dimer, tetramer, and hexamer that precede the Cu(II)-induced amyloid assembly process, results which are distinct from β2m oligomers formed at low pH. Experimental and computational results indicate that the predominant dimer is a Cu(II)-bound structure with an antiparallel side-by-side configuration. In contrast, tetramers exist in solution in both Cu(II)-bound and Cu(II)-free forms. Selective depletion of Cu(II)-bound species results in two primary conformers-one that is compact and another that is more expanded. Molecular modeling and molecular dynamics simulations identify models for these two tetrameric conformers with unique interactions and interfaces that enthalpically compensate for the loss of Cu(II). Unlike with other amyloid systems in which conformational heterogeneity is often associated with different amyloid morphologies or off-pathway events, conformational heterogeneity in the tetramer seems to be a necessary aspect of Cu(II)-induced amyloid formation by β2m. Moreover, the Cu(II)-free models represent a new advance in our understanding of Cu(II) release in Cu(II)-induced amyloid formation, laying a foundation for further mechanistic studies as well as development of new inhibition strategies.
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Affiliation(s)
- Tyler M Marcinko
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States
| | - Chungwen Liang
- Computational and Modeling Core Facility, Institute for Applied Life Sciences, Amherst, MA 01003, United States
| | - Sergey Savinov
- Computational and Modeling Core Facility, Institute for Applied Life Sciences, Amherst, MA 01003, United States; Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, United States
| | - Jianhen Chen
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States; Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, United States
| | - Richard W Vachet
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States.
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20
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Hanozin E, Grifnée E, Gattuso H, Matagne A, Morsa D, Pauw ED. Covalent Cross-Linking as an Enabler for Structural Mass Spectrometry. Anal Chem 2019; 91:12808-12818. [PMID: 31490660 DOI: 10.1021/acs.analchem.9b02491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The number of studies referring to the structural elucidation of intact biomolecular systems using mass spectrometry techniques has gradually increased in the post-2000s literature topics. As part of native mass spectrometry, this domain capitalizes on the kinetic trapping of physiological folds in view of probing solution-like conformational properties of isolated molecules or complexes after their electrospray transfer to the gas phase. Despite its efficiency for a wide array of analytes, this approach is expected to be pushed to its limits when considering highly dynamic systems or when dealing with nonideal operating conditions. To circumvent these limitations, we challenge the adequacy of an original strategy based on cross-linkers to improve the gas-phase stability of isolated proteins and ensure the preservation of folded conformations when measuring with strong transmission voltages, by spraying from denaturing solvents, or trapping for extended periods of time. Tested on cytochrome c, myoglobin, and β-lactoglobulin cross-linked using BS3, we validated the process as structurally nonintrusive in solution using far-ultraviolet circular dichroism and unraveled the preservation of folded conformations showing better resilience to denaturation on cross-linked species using ion mobility. The resulting collision cross sections were found in agreement with the native fold, and a preservation of the proteins' secondary and tertiary structures was evidenced using molecular dynamics simulations. Our results provide new insights concerning the fate of electro-sprayed cross-linked conformers in the gas phase, while constituting promising evidence for the validation of this technique as part of future structural mass spectrometry workflows.
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21
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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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22
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Pukala T. Importance of collision cross section measurements by ion mobility mass spectrometry in structural biology. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33 Suppl 3:72-82. [PMID: 30265417 DOI: 10.1002/rcm.8294] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 09/17/2018] [Accepted: 09/19/2018] [Indexed: 06/08/2023]
Abstract
The field of ion mobility mass spectrometry (IM-MS) has developed rapidly in recent decades, with new fundamental advances underpinning innovative applications. This has been particularly noticeable in the field of biomacromolecular structure determination and structural biology, with pioneering studies revealing new structural insight for complex protein assemblies which control biological function. This perspective offers a review of recent developments in IM-MS which have enabled expanding applications in protein structural biology, principally focusing on the quantitative measurement of collision cross sections and their interpretation to describe higher order protein structures.
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Affiliation(s)
- Tara Pukala
- Discipline of Chemistry, University of Adelaide, North Terrace, Adelaide, South Australia, 5005
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23
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Duez Q, Liénard R, Moins S, Lemaur V, Coulembier O, Cornil J, Gerbaux P, De Winter J. One Step Further in the Characterization of Synthetic Polymers by Ion Mobility Mass Spectrometry: Evaluating the Contribution of End-groups. Polymers (Basel) 2019; 11:E688. [PMID: 30995722 PMCID: PMC6523221 DOI: 10.3390/polym11040688] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 12/20/2022] Open
Abstract
Several families of polymers possessing various end-groups are characterized by ion mobility mass spectrometry (IMMS). A significant contribution of the end-groups to the ion collision cross section (CCS) is observed, although their role is neglected in current fitting models described in literature. Comparing polymers prepared from different synthetic procedures might thus, be misleading with the current theoretical treatments. We show that this issue is alleviated by comparing the CCS of various polymer ions (polyesters and polyethers) as a function of the number of atoms in the macroion instead of the usual representation involving the degree of polymerization. Finally, we extract the atom number density from the spectra which gives us the possibility to evaluate the compaction of polymer ions, and by extension to discern isomeric polymers.
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Affiliation(s)
- Quentin Duez
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Romain Liénard
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Sébastien Moins
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Vincent Lemaur
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Olivier Coulembier
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Pascal Gerbaux
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
| | - Julien De Winter
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMONS, 23 Place du Parc, 7000 Mons, Belgium.
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24
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Haler JRN, Massonnet P, Far J, de la Rosa VR, Lecomte P, Hoogenboom R, Jérôme C, De Pauw E. Gas-Phase Dynamics of Collision Induced Unfolding, Collision Induced Dissociation, and Electron Transfer Dissociation-Activated Polymer Ions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:563-572. [PMID: 30523570 DOI: 10.1007/s13361-018-2115-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/24/2018] [Accepted: 11/24/2018] [Indexed: 06/09/2023]
Abstract
Polymer characterizations are often performed using mass spectrometry (MS). Aside from MS and different tandem MS (MS/MS) techniques, ion mobility-mass spectrometry (IM-MS) has been recently added to the inventory of characterization technique. However, only few studies have focused on the reproducibility and robustness of polymer IM-MS analyses. Here, we perform collisional and electron-mediated activation of polymer ions before measuring IM drift times, collision cross-sections (CCS), or reduced ion mobilities (K0). The resulting IM behavior of different activated product ions is then compared to non-activated native intact polymer ions. First, we analyzed collision induced unfolding (CIU) of precursor ions to test the robustness of polymer ion shapes. Then, we focused on fragmentation product ions to test for shape retentions from the precursor ions: cation ejection species (CES) and product ions with m/z and charge state values identical to native intact polymer ions. The CES species are formed using both collision induced dissociation (CID) and electron transfer dissociation (ETD, formally ETnoD) experiments. Only small drift time, CCS, or K0 deviations between the activated/formed ions are observed compared to the native intact polymer ions. The polymer ion shapes seem to depend solely on their mass and charge state. The experiments were performed on three synthetic homopolymers: poly(ethoxy phosphate) (PEtP), poly(2-n-propyl-2-oxazoline) (Pn-PrOx), and poly(ethylene oxide) (PEO). These results confirm the robustness of polymer ion CCSs for IM calibration, especially singly charged polymer ions. The results are also discussed in the context of polymer analyses, CCS predictions, and probing ion-drift gas interaction potentials. Graphical Abstract.
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Affiliation(s)
- Jean R N Haler
- Mass Spectrometry Laboratory, MolSys Research unit, Quartier Agora, University of Liège, Allée du Six Aout 11, B-4000, Liège, Belgium.
| | - Philippe Massonnet
- Mass Spectrometry Laboratory, MolSys Research unit, Quartier Agora, University of Liège, Allée du Six Aout 11, B-4000, Liège, Belgium
| | - Johann Far
- Mass Spectrometry Laboratory, MolSys Research unit, Quartier Agora, University of Liège, Allée du Six Aout 11, B-4000, Liège, Belgium
| | - Victor R de la Rosa
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000, Ghent, Belgium
| | - Philippe Lecomte
- Center for Education and Research on Macromolecules, CESAM Research Unit, Quartier Agora, University of Liège, Allée du Six Aout 13, B-4000, Liège, Belgium
| | - Richard Hoogenboom
- Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, B-9000, Ghent, Belgium
| | - Christine Jérôme
- Center for Education and Research on Macromolecules, CESAM Research Unit, Quartier Agora, University of Liège, Allée du Six Aout 13, B-4000, Liège, Belgium
| | - Edwin De Pauw
- Mass Spectrometry Laboratory, MolSys Research unit, Quartier Agora, University of Liège, Allée du Six Aout 11, B-4000, Liège, Belgium
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25
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Spratt DE, Barber KR, Marlatt NM, Ngo V, Macklin JA, Xiao Y, Konermann L, Duennwald ML, Shaw GS. A subset of calcium-binding S100 proteins show preferential heterodimerization. FEBS J 2019; 286:1859-1876. [PMID: 30719832 DOI: 10.1111/febs.14775] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 12/19/2018] [Accepted: 01/31/2019] [Indexed: 12/22/2022]
Abstract
The assembly of proteins into dimers and oligomers is a necessary step for the proper function of transcription factors, muscle proteins, and proteases. In uncontrolled states, oligomerization can also contribute to illnesses such as Alzheimer's disease. The S100 protein family is a group of dimeric proteins that have important roles in enzyme regulation, cell membrane repair, and cell growth. Most S100 proteins have been examined in their homodimeric state, yet some of these important proteins are found in similar tissues implying that heterodimeric molecules can also be formed from the combination of two different S100 members. In this work, we have established co-expression methods in order to identify and quantify the distribution of homo- and heterodimers for four specific pairs of S100 proteins in their calcium-free states. The split GFP trap methodology was used in combination with other GFP variants to simultaneously quantify homo- and heterodimeric S100 proteins in vitro and in living cells. For the specific S100 proteins examined, NMR, mass spectrometry, and GFP trap experiments consistently show that S100A1:S100B, S100A1:S100P, and S100A11:S100B heterodimers are the predominant species formed compared to their corresponding homodimers. We expect the tools developed here will help establish the roles of S100 heterodimeric proteins and identify how heterodimerization might alter the specificity for S100 protein action in cells.
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Affiliation(s)
- Donald E Spratt
- Department of Biochemistry, The University of Western Ontario, London, Canada
| | - Kathryn R Barber
- Department of Biochemistry, The University of Western Ontario, London, Canada
| | - Nicole M Marlatt
- Department of Biochemistry, The University of Western Ontario, London, Canada
| | - Vy Ngo
- Department of Pathology and Laboratory Medicine, The University of Western Ontario, London, Canada
| | - Jillian A Macklin
- Department of Biochemistry, The University of Western Ontario, London, Canada
| | - Yiming Xiao
- Department of Chemistry, The University of Western Ontario, London, Canada
| | - Lars Konermann
- Department of Biochemistry, The University of Western Ontario, London, Canada.,Department of Chemistry, The University of Western Ontario, London, Canada
| | - Martin L Duennwald
- Department of Pathology and Laboratory Medicine, The University of Western Ontario, London, Canada
| | - Gary S Shaw
- Department of Biochemistry, The University of Western Ontario, London, Canada
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26
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Bakhtiari M, Konermann L. Protein Ions Generated by Native Electrospray Ionization: Comparison of Gas Phase, Solution, and Crystal Structures. J Phys Chem B 2019; 123:1784-1796. [DOI: 10.1021/acs.jpcb.8b12173] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Maryam Bakhtiari
- 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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27
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Asami H, Kawabata R, Kawauchi N, Kohno JY. Photodissociation Spectroscopy of Hydrated Myoglobin Ions Isolated by IR-laser Ablation of a Droplet Beam: Recovery from pH-denatured Structure by Gas-phase Isolation. CHEM LETT 2019. [DOI: 10.1246/cl.180884] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Hiroya Asami
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Rina Kawabata
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Norishi Kawauchi
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Jun-ya Kohno
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
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28
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Harrison JA, Kelso C, Pukala TL, Beck JL. Conditions for Analysis of Native Protein Structures Using Uniform Field Drift Tube Ion Mobility Mass Spectrometry and Characterization of Stable Calibrants for TWIM-MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:256-267. [PMID: 30324262 DOI: 10.1007/s13361-018-2074-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 09/14/2018] [Accepted: 09/20/2018] [Indexed: 06/08/2023]
Abstract
Determination of collisional cross sections (CCS) by travelling wave ion mobility mass spectrometry (TWIM-MS) requires calibration against standards for which the CCS has been measured previously by drift tube ion mobility mass spectrometry (DTIM-MS). The different extents of collisional activation in TWIM-MS and DTIM-MS can give rise to discrepancies in the CCS of calibrants across the two platforms. Furthermore, the conditions required to ionize and transmit large, folded proteins and assemblies may variably affect the structure of the calibrants and analytes. Stable hetero-oligomeric phospholipase A2 (PDx) and its subunits were characterized as calibrants for TWIM-MS. Conditions for acquisition of native-like TWIM (Synapt G1 HDMS) and DTIM (Agilent 6560 IM-Q-TOF) mass spectra were optimized to ensure the spectra exhibited similar charge state distributions. CCS measurements (DTIM-MS) for ubiquitin, cytochrome c, holo-myoglobin, serum albumin and glutamate dehydrogenase were in good agreement with other recent results determined using this and other DTIM-MS instruments. PDx and its β and γ subunits were stable across a wide range of cone and trap voltages in TWIM-MS and were stable in the presence of organic solvents. The CCS of PDx and its subunits were determined by DTIM-MS and were used as calibrants in determination of CCS of native-like cytochrome c, holo-myoglobin, carbonic anhydrase, serum albumin and haemoglobin in TWIM-MS. The CCS values were in good agreement with those measured by DTIM-MS where available. These experiments demonstrate conditions for analysis of native-like proteins using a commercially available DTIM-MS instrument, characterize robust calibrants for TWIM-MS, and present CCS values determined by DTIM-MS and TWIM-MS for native proteins to add to the current literature database. Graphical Abstract ᅟ.
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Affiliation(s)
- Julian A Harrison
- School of Chemistry, University of Wollongong, Wollongong, NSW, 2522, Australia
- Molecular Horizons, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Celine Kelso
- School of Chemistry, University of Wollongong, Wollongong, NSW, 2522, Australia
- Molecular Horizons, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Tara L Pukala
- Discipline of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jennifer L Beck
- School of Chemistry, University of Wollongong, Wollongong, NSW, 2522, Australia.
- Molecular Horizons, University of Wollongong, Wollongong, NSW, 2522, Australia.
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29
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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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30
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Lim D, Davidson KL, Son S, Ahmed A, Bush MF, Kim S. Determining Collision Cross‐Sections of Aromatic Compounds in Crude Oil by Using Aromatic Compound Mixture as Calibration Standard. B KOREAN CHEM SOC 2018. [DOI: 10.1002/bkcs.11653] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Dongwan Lim
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
| | | | - Seungwoo Son
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
| | - Arif Ahmed
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
| | - Matthew F. Bush
- Department of ChemistryUniversity of Washington Seattle WA, 98195‐1700 USA
| | - Sunghwan Kim
- Department of ChemistryKyungpook National University Daegu 41566 Republic of Korea
- Green‐Nano Materials Research Center Daegu 41566 Republic of Korea
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31
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Corona discharge electrospray ionization of formate-containing solutions enables in-source reduction of disulfide bonds. Anal Bioanal Chem 2018; 411:4729-4737. [PMID: 30397758 DOI: 10.1007/s00216-018-1447-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/12/2018] [Accepted: 10/22/2018] [Indexed: 01/05/2023]
Abstract
Disulfide bonds are critical linkages for maintaining protein structure and enzyme activity. These linkages, however, can limit peptide sequencing efforts by mass spectrometry (MS) and often require chemical reduction and alkylation. Under such conditions, information regarding cysteine connectivity is lost. Online partial disulfide reduction within the electrospray (ESI) source has recently been established as a means to identify complex cysteine linkage patterns in a liquid chromatography-MS experiment without the need for sample pre-treatment. Corona discharge (CD) is invoked as the causative factor of this in-source reduction (ISR); however, evidence remains largely circumstantial. In this study, we demonstrate that instrumental factors-nebulizing gas, ESI capillary material, organic solvent content, ESI spray needle-to-MS distance-all modulate the degree of reduction observed for the single disulfide in oxytocin, further implicating CD in ISR. Rigorous analysis of solution conditions, however, reveals that corona discharge alone can induce only minor disulfide reduction. We establish that CD-ESI of peptide solutions containing formic acid or its conjugate base results in a dramatic increase in disulfide reduction. It is also determined that ISR is exacerbated at low pH for complex peptides containing multiple disulfide bonds and possessing higher-order structure, as well as for a small protein. Overall, our results demonstrate that ESI of formate/formic acid-containing solutions under corona discharge conditions facilitates disulfide ISR, likely by a similar reduction pathway measured in γ-radiolysis studies nearly three decades ago.
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32
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Gabelica V, Livet S, Rosu F. Optimizing Native Ion Mobility Q-TOF in Helium and Nitrogen for Very Fragile Noncovalent Structures. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:2189-2198. [PMID: 30047072 DOI: 10.1007/s13361-018-2029-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/27/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
The amount of internal energy imparted to the ions prior to the ion mobility cell influences the ion structure and thus the collision cross section. Non-covalent complexes with few internal degrees of freedom and/or high charge densities are particularly sensitive to collisional activation. Here, we investigated the effects of virtually all tuning parameters of the Agilent 6560 IM-Q-TOF on the arrival time distributions of ubiquitin7+ and found conditions in which the native state prevails. We discuss the effects of solvent evaporation conditions in the source, of the entire pre-IM DC voltage gradient, of the funnel RF amplitudes. We also report on ubiquitin7+ conformations in different solvents, including native supercharging conditions. Collision-induced unfolding (CIU) can be conveniently provoked either behind the source capillary or in the trapping funnel. The softness of the instrumental conditions behind the mobility cell was further optimized with the DNA G-quadruplex [(dG4T4G4)2·(NH4+)3-8H]5-, for which ion activation results in ammonia loss. To reduce the ion internal energy and obtain the intact 3-NH4+ complex, we reduce the post-IM voltage gradient, but this results in a lower IM resolving power due to increased diffusion behind the drift tube. The article describes the various trade-offs between ion activation, ion transmission, and ion mobility performance for native MS of very fragile structures. Graphical Abstract ᅟ.
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Affiliation(s)
- Valérie Gabelica
- Université de Bordeaux, CNRS, Inserm, Laboratoire Acides Nucléiques: Régulations Naturelle et Artificielle (ARNA, U1212, UMR5320), IECB, 2 rue Robert Escarpit, 33600, Pessac, France.
| | - Sandrine Livet
- Université de Bordeaux, CNRS, Inserm, Laboratoire Acides Nucléiques: Régulations Naturelle et Artificielle (ARNA, U1212, UMR5320), IECB, 2 rue Robert Escarpit, 33600, Pessac, France
- CEA Saclay, DRF/JOLIOT, Service de Pharmacologie et d'Immunoanalyse, 91191, Gif sur Yvette Cedex, France
| | - Frédéric Rosu
- Université de Bordeaux, CNRS, Inserm, Institut Européen de Chimie et Biologie (IECB, UMS3033, US001), 2 rue Robert Escarpit, 33600, Pessac, France
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33
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Lippens JL, Ranganathan SV, D'Esposito RJ, Fabris D. Modular calibrant sets for the structural analysis of nucleic acids by ion mobility spectrometry mass spectrometry. Analyst 2018; 141:4084-99. [PMID: 27152369 DOI: 10.1039/c6an00453a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This study explored the use of modular nucleic acid (NA) standards to generate calibration curves capable of translating primary ion mobility readouts into corresponding collision cross section (CCS) data. Putative calibrants consisted of single- (ss) and double-stranded (ds) oligo-deoxynucleotides reaching up to ∼40 kDa in size (i.e., 64 bp) and ∼5700 Å(2) in CCS. To ensure self-consistency among reference CCS values, computational data obtained in house were preferred to any experimental or computational data from disparate sources. Such values were obtained by molecular dynamics (MD) simulations and either the exact hard sphere scattering (EHSS) or the projection superposition approximation (PSA) methods, and then plotted against the corresponding experimental values to generate separate calibration curves. Their performance was evaluated on the basis of their correlation coefficients and ability to provide values that matched the CCS of selected test samples mimicking typical unknowns. The results indicated that the predictive power benefited from the exclusion of higher charged species that were more susceptible to the destabilizing effects of Coulombic repulsion. The results revealed discrepancies between EHSS and PSA data that were ascribable to the different approximations used to describe the ion mobility process. Within the boundaries defined by these approximations and the challenges of modeling NA structure in a solvent-free environment, the calibrant sets enabled the experimental determination of CCS with excellent reproducibility (precision) and error (accuracy), which will support the analysis of progressively larger NA samples of biological significance.
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Affiliation(s)
| | | | | | - Daniele Fabris
- University at Albany, Albany, New York, USA. and SUNY, Albany, The RNA Institute, 1400 Washington Avenue, Albany, New York, USA
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34
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Hinnenkamp V, Klein J, Meckelmann SW, Balsaa P, Schmidt TC, Schmitz OJ. Comparison of CCS Values Determined by Traveling Wave Ion Mobility Mass Spectrometry and Drift Tube Ion Mobility Mass Spectrometry. Anal Chem 2018; 90:12042-12050. [DOI: 10.1021/acs.analchem.8b02711] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Vanessa Hinnenkamp
- IWW Water Centre, Moritzstraße 26, 45476 Muelheim an der Ruhr, Germany
- Instrumental Analytical Chemistry and Centre for Water and Environmental Research, Universitaetsstrasse 5, 45141 Essen, Germany
| | | | | | - Peter Balsaa
- IWW Water Centre, Moritzstraße 26, 45476 Muelheim an der Ruhr, Germany
| | - Torsten C. Schmidt
- IWW Water Centre, Moritzstraße 26, 45476 Muelheim an der Ruhr, Germany
- Instrumental Analytical Chemistry and Centre for Water and Environmental Research, Universitaetsstrasse 5, 45141 Essen, Germany
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35
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Metwally H, Duez Q, Konermann L. Chain Ejection Model for Electrospray Ionization of Unfolded Proteins: Evidence from Atomistic Simulations and Ion Mobility Spectrometry. Anal Chem 2018; 90:10069-10077. [DOI: 10.1021/acs.analchem.8b02926] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Haidy Metwally
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Quentin Duez
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
- Organic Synthesis and Mass Spectrometry Laboratory, University of Mons, Place du Parc, 23, Mons 7000, Belgium
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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36
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Garabedian A, Baird M, Porter J, Jeanne Dit Fouque K, Shliaha PV, Jensen ON, Williams TD, Fernandez-Lima F, Shvartsburg A. Linear and Differential Ion Mobility Separations of Middle-Down Proteoforms. Anal Chem 2018; 90:2918-2925. [PMID: 29359922 PMCID: PMC6366606 DOI: 10.1021/acs.analchem.7b05224] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Comprehensive characterization of proteomes comprising the same proteins with distinct post-translational modifications (PTMs) is a staggering challenge. Many such proteoforms are isomers (localization variants) that require separation followed by top-down or middle-down mass spectrometric analyses, but condensed-phase separations are ineffective in those size ranges. The variants for "middle-down" peptides were resolved by differential ion mobility spectrometry (FAIMS), relying on the mobility increment at high electric fields, but not previously by linear IMS on the basis of absolute mobility. We now use complete histone tails with diverse PTMs on alternative sites to demonstrate that high-resolution linear IMS, here trapped IMS (TIMS), broadly resolves the variants of ∼50 residues in full or into binary mixtures quantifiable by tandem MS, largely thanks to orthogonal separations across charge states. Separations using traveling-wave (TWIMS) and/or involving various time scales and electrospray ionization source conditions are similar (with lower resolution for TWIMS), showing the transferability of results across linear IMS instruments. The linear IMS and FAIMS dimensions are substantially orthogonal, suggesting FAIMS/IMS/MS as a powerful platform for proteoform analyses.
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Affiliation(s)
- Alyssa Garabedian
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199
| | - Matthew Baird
- Department of Chemistry, Wichita State University, 1845 Fairmount, Wichita, KS 67260
| | - Jacob Porter
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199
| | | | - Pavel V. Shliaha
- Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Ole N. Jensen
- Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Todd D. Williams
- Mass Spectrometry Laboratory, University of Kansas, Lawrence, KS 66045
| | | | - Alexandre Shvartsburg
- Department of Chemistry, Wichita State University, 1845 Fairmount, Wichita, KS 67260
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37
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Eyers CE, Vonderach M, Ferries S, Jeacock K, Eyers PA. Understanding protein–drug interactions using ion mobility–mass spectrometry. Curr Opin Chem Biol 2018; 42:167-176. [DOI: 10.1016/j.cbpa.2017.12.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/08/2017] [Accepted: 12/22/2017] [Indexed: 01/23/2023]
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38
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Fundamentals of ion mobility spectrometry. Curr Opin Chem Biol 2018; 42:51-59. [DOI: 10.1016/j.cbpa.2017.10.022] [Citation(s) in RCA: 186] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 10/13/2017] [Accepted: 10/17/2017] [Indexed: 12/13/2022]
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39
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Ion mobility in the pharmaceutical industry: an established biophysical technique or still niche? Curr Opin Chem Biol 2018; 42:147-159. [DOI: 10.1016/j.cbpa.2017.11.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 11/10/2017] [Accepted: 11/15/2017] [Indexed: 01/01/2023]
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40
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Barroso A, Giménez E, Konijnenberg A, Sancho J, Sanz-Nebot V, Sobott F. Evaluation of ion mobility for the separation of glycoconjugate isomers due to different types of sialic acid linkage, at the intact glycoprotein, glycopeptide and glycan level. J Proteomics 2017; 173:22-31. [PMID: 29197583 DOI: 10.1016/j.jprot.2017.11.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 11/23/2017] [Accepted: 11/24/2017] [Indexed: 02/07/2023]
Abstract
The study of protein glycosylation can be regarded as an intricate but very important task, making glycomics one of the most challenging and interesting, albeit under-researched, type of "omics" science. Complexity escalates remarkably when considering that carbohydrates can form severely branched structures with many different constituents, which often leads to the formation of multiple isomers. In this regard, ion mobility (IM) spectrometry has recently demonstrated its power for the separation of isomeric compounds. In the present work, the potential of traveling wave IM (TWIMS) for the separation of isomeric glycoconjugates was evaluated, using mouse transferrin (mTf) as model glycoprotein. Particularly, we aim to assess the performance of this platform for the separation of isomeric glycoconjugates due to the type of sialic acid linkage, at the intact glycoprotein, glycopeptide and glycan level. Straightforward separation of isomers was achieved with the analysis of released glycans, as opposed to the glycopeptides which showed a more complex pattern. Finally, the developed methodology was applied to serum samples of mice, to investigate its robustness when analyzing real complex samples. BIOLOGICAL SIGNIFICANCE Ion mobility mass spectrometry is a promising analytical technique for the separation of glycoconjugate isomers due to type of sialic acid linkage. The impact of such a small modification in the glycan structure is more evident in smaller analytes, reason why the analysis of free glycans was easier compared to the intact protein or the glycopeptides. The established methodology could be regarded as starting point in the separation of highly decorated glycoconjugates. This is an important topic nowadays, as differences in the abundance of some glycan isomers could be the key for the early diagnosis, control or differentiation of certain diseases, such as inflammation or cancer.
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Affiliation(s)
- Albert Barroso
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Diagonal 645, 08028 Barcelona, Spain
| | - Estela Giménez
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Diagonal 645, 08028 Barcelona, Spain.
| | - Albert Konijnenberg
- Biomolecular & Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium
| | - Jaime Sancho
- Instituto de Parasitología y Biomedicina "López-Neyra" (IPBLN), CSIC, Armilla, Granada, Spain
| | - Victoria Sanz-Nebot
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Diagonal 645, 08028 Barcelona, Spain
| | - Frank Sobott
- Biomolecular & Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium; Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom; School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, United Kingdom.
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41
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Haler JRN, Kune C, Massonnet P, Comby-Zerbino C, Jordens J, Honing M, Mengerink Y, Far J, De Pauw E. Comprehensive Ion Mobility Calibration: Poly(ethylene oxide) Polymer Calibrants and General Strategies. Anal Chem 2017; 89:12076-12086. [DOI: 10.1021/acs.analchem.7b02564] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jean R. N. Haler
- Mass
Spectrometry Laboratory, University of Liège, Quartier Agora, Allée du
Six Aout 11, B-4000 Liège, Belgium
| | - Christopher Kune
- Mass
Spectrometry Laboratory, University of Liège, Quartier Agora, Allée du
Six Aout 11, B-4000 Liège, Belgium
| | - Philippe Massonnet
- Mass
Spectrometry Laboratory, University of Liège, Quartier Agora, Allée du
Six Aout 11, B-4000 Liège, Belgium
| | - Clothilde Comby-Zerbino
- Institut
Lumière Matière, Université de Lyon, Université Lyon 1, CNRS, 69100 Villeurbanne, France
| | | | | | | | - Johann Far
- Mass
Spectrometry Laboratory, University of Liège, Quartier Agora, Allée du
Six Aout 11, B-4000 Liège, Belgium
| | - Edwin De Pauw
- Mass
Spectrometry Laboratory, University of Liège, Quartier Agora, Allée du
Six Aout 11, B-4000 Liège, Belgium
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42
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Duez Q, Chirot F, Liénard R, Josse T, Choi C, Coulembier O, Dugourd P, Cornil J, Gerbaux P, De Winter J. Polymers for Traveling Wave Ion Mobility Spectrometry Calibration. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:2483-2491. [PMID: 28762031 DOI: 10.1007/s13361-017-1762-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/30/2017] [Accepted: 07/09/2017] [Indexed: 06/07/2023]
Abstract
One of the main issues when using traveling wave ion mobility spectrometry (TWIMS) for the determination of collisional cross-section (CCS) concerns the need for a robust calibration procedure built from referent ions of known CCS. Here, we implement synthetic polymer ions as CCS calibrants in positive ion mode. Based on their intrinsic polydispersities, polymers offer in a single sample the opportunity to generate, upon electrospray ionization, numerous ions covering a broad mass range and a large CCS window for different charge states at a time. In addition, the key advantage of polymer ions as CCS calibrants lies in the robustness of their gas-phase structure with respect to the instrumental conditions, making them less prone to collisional-induced unfolding (CIU) than protein ions. In this paper, we present a CCS calibration procedure using sodium cationized polylactide and polyethylene glycol, PLA and PEG, as calibrants with reference CCS determined on a home-made drift tube. Our calibration procedure is further validated by testing the polymer calibration to determine CCS of numerous different ions for which CCS are reported in the literature. Graphical Abstract ᅟ.
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Affiliation(s)
- Quentin Duez
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium
| | - Fabien Chirot
- Université Lyon, Université Claude Bernard Lyon 1, ENS de Lyon, CNRS, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100, Villeurbanne, France
| | - Romain Liénard
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - Thomas Josse
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - ChangMin Choi
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Lyon, France
| | - Olivier Coulembier
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - Philippe Dugourd
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Lyon, France
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium
| | - Pascal Gerbaux
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium
| | - Julien De Winter
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons (UMons), Place du Parc, 23, Mons, 7000, Belgium.
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43
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Marcinko TM, Dong J, LeBlanc R, Daborowski KV, Vachet RW. Small molecule-mediated inhibition of β-2-microglobulin-based amyloid fibril formation. J Biol Chem 2017; 292:10630-10638. [PMID: 28468825 DOI: 10.1074/jbc.m116.774083] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 05/02/2017] [Indexed: 12/26/2022] Open
Abstract
In dialysis patients, β-2 microglobulin (β2m) can aggregate and eventually form amyloid fibrils in a condition known as dialysis-related amyloidosis, which deleteriously affects joint and bone function. Recently, several small molecules have been identified as potential inhibitors of β2m amyloid formation in vitro Here we investigated whether these molecules are more broadly applicable inhibitors of β2m amyloid formation by studying their effect on Cu(II)-induced β2m amyloid formation. Using a variety of biophysical techniques, we also examined their inhibitory mechanisms. We found that two molecules, doxycycline and rifamycin SV, can inhibit β2m amyloid formation in vitro by causing the formation of amorphous, redissolvable aggregates. Rather than interfering with β2m amyloid formation at the monomer stage, we found that doxycycline and rifamycin SV exert their effect by binding to oligomeric species both in solution and in gas phase. Their binding results in a diversion of the expected Cu(II)-induced progression of oligomers toward a heterogeneous collection of oligomers, including trimers and pentamers, that ultimately matures into amorphous aggregates. Using ion mobility mass spectrometry, we show that both inhibitors promote the compaction of the initially formed β2m dimer, which causes the formation of other off-pathway and amyloid-incompetent oligomers that are isomeric with amyloid-competent oligomers in some cases. Overall, our results suggest that doxycycline and rifamycin are general inhibitors of Cu(II)-induced β2m amyloid formation. Interestingly, the putative mechanism of their activity is different depending on how amyloid formation is initiated with β2m, which underscores the complexity of how these structures assemble in vitro.
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Affiliation(s)
- Tyler M Marcinko
- From the Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Jia Dong
- From the Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Raquel LeBlanc
- From the Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Kate V Daborowski
- From the Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Richard W Vachet
- From the Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
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44
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Van der Rest G, Rezaei H, Halgand F. Monitoring Conformational Landscape of Ovine Prion Protein Monomer Using Ion Mobility Coupled to Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:303-314. [PMID: 27757822 DOI: 10.1007/s13361-016-1522-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 10/05/2016] [Accepted: 10/06/2016] [Indexed: 06/06/2023]
Abstract
Prion protein is involved in deadly neurodegenerative diseases. Its pathogenicity is linked to its structural conversion (α-helix to β-strand transition). However, recent studies suggest that prion protein can follow a plurality of conversion pathways, which hints towards different conformers that might coexist in solution. To gain insights on the plasticity of the ovine prion protein (PrP) monomer, wild type (A136, R154, Q171), mutants and deletions of ARQ were studied by traveling wave ion mobility experiments coupled to mass spectrometry. In order to perform the analysis of a large body of data sets, we designed and evaluated the performance of a processing pipeline based on Driftscope peak detection and a homemade script for automated peak assignment, annotation, and quantification on specific multiply charged protein data. Using this approach, we showed that in the gas phase, PrPs are represented by at least three conformer families differing in both charge state distribution and collisional cross-section, in agreement with the work of Hilton et al. (2010). We also showed that this plasticity is borne both by the N- and C-terminal domains. Effect of protein concentration, pH and temperature were also assessed, showing that (1) pH does not affect conformer distributions, (2) protein concentration modifies the conformational landscape of one mutant (I208M) only, and (3) heating leads to other unfolded species and to a modification of the conformer intensity ratios. Graphical Abstract ᅟ.
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Affiliation(s)
- Guillaume Van der Rest
- Laboratoire de Chimie Physique, Université Paris Sud, CNRS UMR 8000, 91405, Orsay, France
| | - Human Rezaei
- Institut National de la Recherche Agronomique, UR892, Virologie Immunologie Moléculaires, Domaine de Vilvert, 78350, Jouy-en-Josas, France
| | - Frédéric Halgand
- Laboratoire de Chimie Physique, Université Paris Sud, CNRS UMR 8000, 91405, Orsay, France.
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45
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Ngo ST, Hung HM, Tran KN, Nguyen MT. Replica exchange molecular dynamics study of the amyloid beta (11–40) trimer penetrating a membrane. RSC Adv 2017. [DOI: 10.1039/c6ra26461a] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The transmembrane Aβ11–40 trimer is investigated for the first time using REMD and FEP.
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Affiliation(s)
- Son Tung Ngo
- Computational Chemistry Research Group
- Ton Duc Thang University
- Ho Chi Minh City
- Vietnam
- Faculty of Applied Sciences
| | | | - Khoa Nhat Tran
- Department of Biological Sciences
- University of Maryland Baltimore County
- 21250 Baltimore
- USA
| | - Minh Tho Nguyen
- Computational Chemistry Research Group
- Ton Duc Thang University
- Ho Chi Minh City
- Vietnam
- Faculty of Applied Sciences
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46
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Bartman CE, Metwally H, Konermann L. Effects of Multidentate Metal Interactions on the Structure of Collisionally Activated Proteins: Insights from Ion Mobility Spectrometry and Molecular Dynamics Simulations. Anal Chem 2016; 88:6905-13. [DOI: 10.1021/acs.analchem.6b01627] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Claire E. Bartman
- 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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47
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Allison TM, Landreh M, Benesch JLP, Robinson CV. Low Charge and Reduced Mobility of Membrane Protein Complexes Has Implications for Calibration of Collision Cross Section Measurements. Anal Chem 2016; 88:5879-5884. [PMID: 27153188 DOI: 10.1021/acs.analchem.6b00691] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Ion mobility mass spectrometry of integral membrane proteins provides valuable insights into their architecture and stability. Here we show that, due to their lower charge, the average mobility of native-like membrane protein ions is approximately 30% lower than that of soluble proteins of similar mass. This has implications for drift time measurements, made on traveling wave ion mobility mass spectrometers, which have to be calibrated to extract collision cross sections (Ω). Common calibration strategies employ unfolded or native-like soluble protein standards with masses and mobilities comparable to the protein of interest. We compare Ω values for membrane proteins, derived from standard calibration protocols using soluble proteins, to values measured using an RF-confined drift tube. Our results demonstrate that, while common calibration methods underestimate Ω for native-like or unfolded membrane protein complexes, higher mass soluble calibration standards consistently yield more accurate Ω values. These findings enable us to obtain directly structural information for highly charge-reduced complexes by traveling wave ion mobility mass spectrometry.
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Affiliation(s)
- Timothy M Allison
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom
| | - Michael Landreh
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom
| | - Justin L P Benesch
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom
| | - Carol V Robinson
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom
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48
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Wagner ND, Kim D, Russell DH. Increasing Ubiquitin Ion Resistance to Unfolding in the Gas Phase Using Chloride Adduction: Preserving More "Native-Like" Conformations Despite Collisional Activation. Anal Chem 2016; 88:5934-40. [PMID: 27137645 DOI: 10.1021/acs.analchem.6b00871] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Electrospray ionization (ESI) of ubiquitin from acidified (0.1%) aqueous solution produces abundant ubiquitin-chloride adduct ions, [M + nH + xCl]((n - x)+), that upon mild heating react via elimination of neutral HCl. Ion mobility collision cross section (CCS) measurements show that ubiquitin ions retaining chloride adducts exhibit CCS values similar to those of the "native-state" of the protein. Coupled with results from recent molecular dynamics (MD) simulations for the evolution of a salt-containing electrospray droplet, this study provides a more complete picture for how the presence of salts affects the evolution of protein conformers in the final stages of dehydration of the ESI process and within the instrument.
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Affiliation(s)
- Nicole D Wagner
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Doyong Kim
- 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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49
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Metwally H, McAllister RG, Popa V, Konermann L. Mechanism of Protein Supercharging by Sulfolane and m-Nitrobenzyl Alcohol: Molecular Dynamics Simulations of the Electrospray Process. Anal Chem 2016; 88:5345-54. [DOI: 10.1021/acs.analchem.6b00650] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Haidy Metwally
- Department
of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Robert G. McAllister
- Department
of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Vlad Popa
- Department
of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Lars Konermann
- Department
of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
- Department
of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
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