1
|
Jeon CK, Rojas Ramirez C, Makey DM, Kurulugama RT, Ruotolo BT. CIUSuite 3: Next-Generation CCS Calibration and Automated Data Analysis Tools for Gas-Phase Protein Unfolding Data. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1865-1874. [PMID: 38967378 DOI: 10.1021/jasms.4c00176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
Ion mobility-mass spectrometry (IM-MS) has become a technology deployed across a wide range of structural biology applications despite the challenges in characterizing closely related protein structures. Collision-induced unfolding (CIU) has emerged as a valuable technique for distinguishing closely related, iso-cross-sectional protein and protein complex ions through their distinct unfolding pathways in the gas phase. With the speed and sensitivity of CIU analyses, there has been a rapid growth of CIU-based assays, especially regarding biomolecular targets that remain challenging to assess and characterize with other structural biology tools. With information-rich CIU data, many software tools have been developed to automate laborious data analysis. However, with the recent development of new IM-MS technologies, such as cyclic IM-MS, CIU continues to evolve, necessitating improved data analysis tools to keep pace with new technologies and facilitating the automation of various data processing tasks. Here, we present CIUSuite 3, a software package that contains updated algorithms that support various IM-MS platforms and supports the automation of various data analysis tasks such as peak detection, multidimensional classification, and collision cross section (CCS) calibration. CIUSuite 3 uses local maxima searches along with peak width and prominence filters to detect peaks to automate CIU data extraction. To support both the primary CIU (CIU1) and secondary CIU (CIU2) experiments enabled by cyclic IM-MS, two-dimensional data preprocessing is deployed, which allows multidimensional classification. Our data suggest that additional dimensions in classification improve the overall accuracy of class assignments. CIUSuite 3 also supports CCS calibration for both traveling wave and drift tube IM-MS, and we demonstrate the accuracy of a new single-field CCS calibration method designed for drift tube IM-MS leveraging calibrant CIU data. Overall, CIUSuite 3 is positioned to support current and next-generation IM-MS and CIU assay development deployed in an automated format.
Collapse
Affiliation(s)
- Chae Kyung Jeon
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | - Devin M Makey
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
Schrader R, Walker TE, Chakravorty S, Anderson GA, Reilly PTA, Russell DH. Optimization of a Digital Mass Filter for the Isolation of Intact Protein Complexes in Stability Zone 1,1. Anal Chem 2023; 95:3062-3068. [PMID: 36701646 PMCID: PMC9983038 DOI: 10.1021/acs.analchem.2c05221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 01/13/2023] [Indexed: 01/27/2023]
Abstract
Digital mass filters are advantageous for the analysis of large molecules due to the ability to perform ion isolation of high-m/z ions without the generation of very high radio frequency (RF) and DC voltages. Experimentally determined Mathieu stability diagrams of stability zone 1,1 for capacitively coupled digital waveforms show a voltage offset between the quadrupole rod pairs is introduced by the capacitors which is dependent on the voltage magnitude of the waveform and the duty cycle. This changes the ion's a value from a = 0 to a < 0. These effects are illustrated for isolation for single-charge states for various protein complexes up to 800 kDa (GroEL) for stability zone 1,1. Isolation resolving power (m/Δm) of approximately 280 was achieved for an ion of m/z 12,315 (z = 65+ for 800.5 kDa GroEL D398A), which corresponds to an m/z window of 44.
Collapse
Affiliation(s)
- Robert
L. Schrader
- Department
of Chemistry, Texas A&M University, College Station, Texas77843, United States
| | - Thomas E. Walker
- Department
of Chemistry, Texas A&M University, College Station, Texas77843, United States
| | - Sumeet Chakravorty
- Department
of Chemistry, Washington State University, Pullman, Washington99164, United States
| | | | - Peter T. A. Reilly
- Department
of Chemistry, Washington State University, Pullman, Washington99164, United States
| | - David H. Russell
- Department
of Chemistry, Texas A&M University, College Station, Texas77843, United States
| |
Collapse
|
4
|
Cheung See Kit M, Webb IK. Application of Multiple Length Cross-linkers to the Characterization of Gaseous Protein Structure. Anal Chem 2022; 94:13301-13310. [DOI: 10.1021/acs.analchem.2c03044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Melanie Cheung See Kit
- Department of Chemistry and Chemical Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Ian K. Webb
- Department of Chemistry and Chemical Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, Indiana 46202, United States
| |
Collapse
|
5
|
McCabe JW, Hebert MJ, Shirzadeh M, Mallis CS, Denton JK, Walker TE, Russell DH. THE IMS PARADOX: A PERSPECTIVE ON STRUCTURAL ION MOBILITY-MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2021; 40:280-305. [PMID: 32608033 PMCID: PMC7989064 DOI: 10.1002/mas.21642] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/03/2020] [Indexed: 05/06/2023]
Abstract
Studies of large proteins, protein complexes, and membrane protein complexes pose new challenges, most notably the need for increased ion mobility (IM) and mass spectrometry (MS) resolution. This review covers evolutionary developments in IM-MS in the authors' and key collaborators' laboratories with specific focus on developments that enhance the utility of IM-MS for structural analysis. IM-MS measurements are performed on gas phase ions, thus "structural IM-MS" appears paradoxical-do gas phase ions retain their solution phase structure? There is growing evidence to support the notion that solution phase structure(s) can be retained by the gas phase ions. It should not go unnoticed that we use "structures" in this statement because an important feature of IM-MS is the ability to deal with conformationally heterogeneous systems, thus providing a direct measure of conformational entropy. The extension of this work to large proteins and protein complexes has motivated our development of Fourier-transform IM-MS instruments, a strategy first described by Hill and coworkers in 1985 (Anal Chem, 1985, 57, pp. 402-406) that has proved to be a game-changer in our quest to merge drift tube (DT) and ion mobility and the high mass resolution orbitrap MS instruments. DT-IMS is the only method that allows first-principles determinations of rotationally averaged collision cross sections (CSS), which is essential for studies of biomolecules where the conformational diversities of the molecule precludes the use of CCS calibration approaches. The Fourier transform-IM-orbitrap instrument described here also incorporates the full suite of native MS/IM-MS capabilities that are currently employed in the most advanced native MS/IM-MS instruments. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.
Collapse
Affiliation(s)
- Jacob W McCabe
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - Michael J Hebert
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - Mehdi Shirzadeh
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | | | - Joanna K Denton
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - Thomas E Walker
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| | - David H Russell
- Department of Chemistry, Texas A&M University, College Station, TX, 77843
| |
Collapse
|
6
|
Dong S, Shirzadeh M, Fan L, Laganowsky A, Russell DH. Ag + Ion Binding to Human Metallothionein-2A Is Cooperative and Domain Specific. Anal Chem 2020; 92:8923-8932. [PMID: 32515580 PMCID: PMC8114364 DOI: 10.1021/acs.analchem.0c00829] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Metallothioneins (MTs) constitute a family of cysteine-rich proteins that play key biological roles for a wide range of metal ions, but unlike many other metalloproteins, the structures of apo- and partially metalated MTs are not well understood. Here, we combine nano-electrospray ionization-mass spectrometry (ESI-MS) and nano-ESI-ion mobility (IM)-MS with collision-induced unfolding (CIU), chemical labeling using N-ethylmaleimide (NEM), and both bottom-up and top-down proteomics in an effort to better understand the metal binding sites of the partially metalated forms of human MT-2A, viz., Ag4-MT. The results for Ag4-MT are then compared to similar results obtained for Cd4-MT. The results show that Ag4-MT is a cooperative product, and data from top-down and bottom-up proteomics mass spectrometry analysis combined with NEM labeling revealed that all four Ag+ ions of Ag4-MT are bound to the β-domain. The binding sites are identified as Cys13, Cys15, Cys19, Cys21, Cys24, and Cys26. While both Ag+ and Cd2+ react with MT to yield cooperative products, i.e., Ag4-MT and Cd4-MT, these products are very different; Ag+ ions of Ag4-MT are located in the β-domain, whereas Cd2+ ions of Cd4-MT are located in the α-domain. Ag6-MT has been reported to be fully metalated in the β-domain, but our data suggest the two additional Ag+ ions are more weakly bound than are the other four. Higher order Agi-MT complexes (i = 7-17) are formed in solutions that contain excess Ag+ ions, and these are assumed to be bound to the α-domain or shared between the two domains. Interestingly, the excess Ag+ ions are displaced upon addition of NEM to this solution to yield predominantly Ag4NEM14-MT. Results from CIU suggest that Agi-MT complexes are structurally more ordered and that the energy required to unfold these complexes increases as the number of coordinated Ag+ increases.
Collapse
Affiliation(s)
- Shiyu Dong
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Mehdi Shirzadeh
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Liqi Fan
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Arthur Laganowsky
- 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
| |
Collapse
|
7
|
Saha A, Oanca G, Mondal D, Warshel A. Exploring the Proteolysis Mechanism of the Proteasomes. J Phys Chem B 2020; 124:5626-5635. [PMID: 32498514 DOI: 10.1021/acs.jpcb.0c04435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The proteasome is a key protease in the eukaryotic cells which is responsible for various important cellular processes such as the control of the cell cycle, immune responses, protein homeostasis, inflammation, apoptosis, and the response to proteotoxic stress. Acting as a major molecular machine for protein degradation, proteasome first identifies damaged or obsolete regulatory proteins by attaching ubiquitin chains and subsequently utilizes conserved pore loops of the heterohexameric ring of AAA+ (ATPases associated with diverse cellular activities) to pull and mechanically unfold and translocate the misfolded protein to the active site for proteolysis. A detailed knowledge of the reaction mechanism for this proteasomal proteolysis is of central importance, both for fundamental understanding and for drug discovery. The present study investigates the mechanism of the proteolysis by the proteasome with full consideration of the protein's flexibility and its impact on the reaction free energy. Major attention is paid to the role of the protein electrostatics in determining the activation barriers. The reaction mechanism is studied by considering a small artificial fluorogenic peptide substrate (Suc-LLVY-AMC) and evaluating the activation barriers and reaction free energies for the acylation and deacylation steps, by using the empirical valence bond method. Our results shed light on the proteolysis mechanism and thus should be important for further studies of the proteasome action.
Collapse
Affiliation(s)
- Arjun Saha
- Department of Chemistry, University of Southern California, 418 SGM Building, 3620 McClintock Ave., Los Angeles, California 90089-1062, United States
| | - Gabriel Oanca
- Department of Chemistry, University of Southern California, 418 SGM Building, 3620 McClintock Ave., Los Angeles, California 90089-1062, United States
| | - Dibyendu Mondal
- Department of Chemistry, University of Southern California, 418 SGM Building, 3620 McClintock Ave., Los Angeles, California 90089-1062, United States
| | - Arieh Warshel
- Department of Chemistry, University of Southern California, 418 SGM Building, 3620 McClintock Ave., Los Angeles, California 90089-1062, United States
| |
Collapse
|
8
|
Shine A, Shenoy J, Jayan P, Jiji AC, Vijayan V. Residual Dipolar‐Coupling‐Based Conformational Comparison of Noncovalent Ubiquitin Homodimer with Covalently Linked Diubiquitin. Chemphyschem 2020; 21:888-894. [DOI: 10.1002/cphc.201901100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/06/2020] [Indexed: 11/08/2022]
Affiliation(s)
- A. Shine
- School of Chemistry IISER Thiruvananthapuram Maruthamala PO Vithura Kerala India
| | - J. Shenoy
- School of Chemistry IISER Thiruvananthapuram Maruthamala PO Vithura Kerala India
| | - Parvathy Jayan
- School of Chemistry IISER Thiruvananthapuram Maruthamala PO Vithura Kerala India
| | - A. C. Jiji
- School of Chemistry IISER Thiruvananthapuram Maruthamala PO Vithura Kerala India
| | - Vinesh Vijayan
- School of Chemistry IISER Thiruvananthapuram Maruthamala PO Vithura Kerala India
| |
Collapse
|
9
|
Paissoni C, Jussupow A, Camilloni C. Determination of Protein Structural Ensembles by Hybrid-Resolution SAXS Restrained Molecular Dynamics. J Chem Theory Comput 2020; 16:2825-2834. [PMID: 32119546 PMCID: PMC7997378 DOI: 10.1021/acs.jctc.9b01181] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
![]()
Small-angle
X-ray scattering (SAXS) experiments provide low-resolution
but valuable information about the dynamics of biomolecular systems,
which could be ideally integrated into molecular dynamics (MD) simulations
to accurately determine conformational ensembles of flexible proteins.
The applicability of this strategy is hampered by the high computational
cost required to calculate scattering intensities from three-dimensional
structures. We previously presented a hybrid resolution method that
makes atomistic SAXS-restrained MD simulation feasible by adopting
a coarse-grained approach to efficiently back-calculate scattering
intensities; here, we extend this technique, applying it in the framework
of metainference with the aim to investigate the dynamical behavior
of flexible biomolecules. The efficacy of the method is assessed on
the K63-diubiquitin, showing that the inclusion of SAXS restraints
is effective in generating a reliable conformational ensemble, improving
the agreement with independent experimental data.
Collapse
Affiliation(s)
- Cristina Paissoni
- Dipartimento di Bioscienze, Università degli Studi di Milano, via Celoria 26, 20133 Milano, Italy
| | - Alexander Jussupow
- Department of Chemistry and Institute of Advanced Study, Technical University of Munich, Garching 85747, Germany
| | - Carlo Camilloni
- Dipartimento di Bioscienze, Università degli Studi di Milano, via Celoria 26, 20133 Milano, Italy
| |
Collapse
|
10
|
Hebert MJ, Russell DH. Tracking the Structural Evolution of 4-Aminobenzoic Acid in the Transition from Solution to the Gas Phase. J Phys Chem B 2020; 124:2081-2087. [DOI: 10.1021/acs.jpcb.9b10576] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Michael J. Hebert
- 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
| |
Collapse
|
11
|
Vallejo DD, Polasky DA, Kurulugama RT, Eschweiler JD, Fjeldsted JC, Ruotolo BT. A Modified Drift Tube Ion Mobility-Mass Spectrometer for Charge-Multiplexed Collision-Induced Unfolding. Anal Chem 2019; 91:8137-8146. [PMID: 31194508 DOI: 10.1021/acs.analchem.9b00427] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Collision-induced unfolding (CIU) of protein ions and their noncovalent complexes offers relatively rapid access to a rich portfolio of biophysical information, without the need to tag or purify proteins prior to analysis. Such assays have been characterized extensively for a range of therapeutic proteins, proving exquisitely sensitive to alterations in protein sequence, structure, and post-translational modification state. Despite advantages over traditional probes of protein stability, improving the throughput and information content of gas-phase protein unfolding assays remains a challenge for current instrument platforms. In this report, we describe modifications to an Agilent 6560 drift tube ion mobility-mass spectrometer in order to perform robust, simultaneous CIU across all precursor ions detected. This approach dramatically increases the speed associated with typical CIU assays, which typically involve mass selection of narrow m/ z regions prior to collisional activation, and thus their development requires a comprehensive assessment of charge-stripping reactions that can unintentionally pollute CIU data with chemical noise when more than one precursor ion is allowed to undergo simultaneous activation. By studying the unfolding and dissociation of intact antibody ions, a key analyte class associated with biotherapeutics, we reveal a predictive relationship between the precursor charge state, the amount of buffer components bound to the ions of interest, and the amount of charge stripping detected. We then utilize our knowledge of antibody charge stripping to rapidly capture CIU data for a range of antibody subclasses and subtypes across all charge states simultaneously, demonstrating a strong charge state dependence on the information content of CIU. Finally, we demonstrate that CIU data collection times can be further reduced by scanning fewer voltage steps, enabling us to optimize the throughput of our improved CIU methods and confidently differentiate antibody variant ions using ∼20% of the data typically collected during CIU. Taken together, our results characterize a new instrument platform for biotherapeutic stability measurements with dramatically improved throughput and information content.
Collapse
Affiliation(s)
- Daniel D Vallejo
- Department of Chemistry , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Daniel A Polasky
- Department of Chemistry , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
| | | | - Joseph D Eschweiler
- Department of Chemistry , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States.,AbbVie , North Chicago , Illinois 60064 , United States
| | - John C Fjeldsted
- Agilent Technologies , Santa Clara , California 95051 , United States
| | - Brandon T Ruotolo
- Department of Chemistry , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , United States
| |
Collapse
|
12
|
Hebert MJ, Russell DH. Hydration of Guanidinium Ions: An Experimental Search for Like-Charged Ion Pairs. J Phys Chem Lett 2019; 10:1349-1354. [PMID: 30840463 DOI: 10.1021/acs.jpclett.9b00268] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Guanidinium ions (GdmH+) are reported to form stable complexes (GdmH+/GdmH+) in aqueous solution despite strong repulsive interactions between the like-charged centers. These complexes are thought to play important roles in protein folding, membrane penetration, and formation of protein dimers. Although GdmH+ ions are weakly hydrated, semiempirical calculations provide evidence that these like-charged complexes are stabilized by water molecules, which serve important structural and energetic roles. Specifically, water molecules bridge between the GdmH+ ions of GdmH+/GdmH+ complexes as well as complexes involving the guanidinium side chains of arginine. Potential biological significances of like-charged complexes have been largely confirmed by ab initio molecular dynamics simulations and indirect experimental evidence. We report cryo-ion mobility-mass spectrometry results for the GdmH+/GdmH+ ion pair confined in a nanodroplet- the first direct experimental observation of this like-charged complex. A second like-charged complex, described as a water-mediated complex involving GdmH+ and H3O+, was also observed.
Collapse
Affiliation(s)
- Michael J Hebert
- 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
| |
Collapse
|
13
|
Polasky DA, Dixit SM, Fantin SM, Ruotolo BT. CIUSuite 2: Next-Generation Software for the Analysis of Gas-Phase Protein Unfolding Data. Anal Chem 2019; 91:3147-3155. [DOI: 10.1021/acs.analchem.8b05762] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Daniel A. Polasky
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Sugyan M. Dixit
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Sarah M. Fantin
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Brandon T. Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
14
|
Wagner ND, Clemmer DE, Russell DH. ESI-IM-MS and Collision-Induced Unfolding That Provide Insight into the Linkage-Dependent Interfacial Interactions of Covalently Linked Diubiquitin. Anal Chem 2017; 89:10094-10103. [DOI: 10.1021/acs.analchem.7b02932] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Nicole D. Wagner
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - David E. Clemmer
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - David H. Russell
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| |
Collapse
|