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Carlsson JA, Löfgren M, Amini A. Identity verification of monoclonal antibodies by triple injection capillary zone electrophoresis. J Sep Sci 2024; 47:e2400092. [PMID: 38819776 DOI: 10.1002/jssc.202400092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 04/16/2024] [Accepted: 04/18/2024] [Indexed: 06/01/2024]
Abstract
This paper presents an approach based on triple injection capillary zone electrophoresis for identification of monoclonal antibodies. The analyte to be identified is injected between two zones of a known reference. The distances between the reference zones (plug I and III) and the target zone (plug II) are adjusted by partial electrophoresis of the first and second injection plugs. The full migration time of the target analyte is calculated from the observed migration time by considering the migration times of the reference in the first and third injection plugs. The relative migration time, that is, the ratio between the full migration time of the analyte and the migration time of the reference in the third injection plug provides the basis for identification. Here, eight monoclonal antibodies, including a pair of biosimilars, were used interchangeably as both analyte and reference to investigate potential of the method. The relative migration time for a preliminary positive identification were found to vary between 0.994 and 1.006 (1.000 ± 0.006, p = 95%). Beside the relative migration time, isoform distribution, peak profiles, and early migrating peaks, originating from components in the pharmaceutical formulations, were successfully used to verify the identity of all tested monoclonal antibodies.
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Affiliation(s)
| | | | - Ahmad Amini
- Swedish Medical Products Agency, Uppsala, Sweden
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2
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Collars OA, Jones BS, Hu DD, Weaver SD, Sherman TA, Champion MM, Champion PA. An N-acetyltransferase required for ESAT-6 N-terminal acetylation and virulence in Mycobacterium marinum. mBio 2023; 14:e0098723. [PMID: 37772840 PMCID: PMC10653941 DOI: 10.1128/mbio.00987-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/09/2023] [Indexed: 09/30/2023] Open
Abstract
IMPORTANCE N-terminal acetylation is a protein modification that broadly impacts basic cellular function and disease in higher organisms. Although bacterial proteins are N-terminally acetylated, little is understood how N-terminal acetylation impacts bacterial physiology and pathogenesis. Mycobacterial pathogens cause acute and chronic disease in humans and in animals. Approximately 15% of mycobacterial proteins are N-terminally acetylated, but the responsible enzymes are largely unknown. We identified a conserved mycobacterial protein required for the N-terminal acetylation of 23 mycobacterial proteins including the EsxA virulence factor. Loss of this enzyme from M. marinum reduced macrophage killing and spread of M. marinum to new host cells. Defining the acetyltransferases responsible for the N-terminal protein acetylation of essential virulence factors could lead to new targets for therapeutics against mycobacteria.
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Affiliation(s)
- Owen A. Collars
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
| | - Bradley S. Jones
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
| | - Daniel D. Hu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Simon D. Weaver
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Taylor A. Sherman
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Matthew M. Champion
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
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3
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Collars OA, Jones BS, Hu DD, Weaver SD, Champion MM, Champion PA. An N-acetyltransferase required for EsxA N-terminal protein acetylation and virulence in Mycobacterium marinum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532585. [PMID: 36993388 PMCID: PMC10055061 DOI: 10.1101/2023.03.14.532585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
N-terminal protein acetylation is a ubiquitous post-translational modification that broadly impacts diverse cellular processes in higher organisms. Bacterial proteins are also N-terminally acetylated, but the mechanisms and consequences of this modification in bacteria are poorly understood. We previously quantified widespread N-terminal protein acetylation in pathogenic mycobacteria (C. R. Thompson, M. M. Champion, and P.A. Champion, J Proteome Res 17(9): 3246-3258, 2018, https:// doi: 10.1021/acs.jproteome.8b00373). The major virulence factor EsxA (ESAT-6, Early secreted antigen, 6kDa) was one of the first N-terminally acetylated proteins identified in bacteria. EsxA is conserved in mycobacterial pathogens, including Mycobacterium tuberculosis and Mycobacterium marinum, a non-tubercular mycobacterial species that causes tuberculosis-like disease in ectotherms. However, enzyme responsible for EsxA N-terminal acetylation has been elusive. Here, we used genetics, molecular biology, and mass-spectroscopy based proteomics to demonstrate that MMAR_1839 (renamed Emp1, ESX-1 modifying protein, 1) is the putative N-acetyl transferase (NAT) solely responsible for EsxA acetylation in Mycobacterium marinum. We demonstrated that ERD_3144, the orthologous gene in M. tuberculosis Erdman, is functionally equivalent to Emp1. We identified at least 22 additional proteins that require Emp1 for acetylation, demonstrating that this putative NAT is not dedicated to EsxA. Finally, we showed that loss of emp1 resulted in a significant reduction in the ability of M. marinum to cause macrophage cytolysis. Collectively, this study identified a NAT required for N-terminal acetylation in Mycobacterium and provided insight into the requirement of N-terminal acetylation of EsxA and other proteins in mycobacterial virulence in the macrophage.
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Affiliation(s)
- Owen A. Collars
- Department of Biological Sciences, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
| | - Bradley S. Jones
- Department of Biological Sciences, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
| | - Daniel D. Hu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, USA
| | - Simon D. Weaver
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, USA
| | - Matthew M. Champion
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
| | - Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
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4
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Ryan KA, Bruening ML. Online protein digestion in membranes between capillary electrophoresis and mass spectrometry. Analyst 2023; 148:1611-1619. [PMID: 36912593 DOI: 10.1039/d3an00106g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
Abstract
This research employs pepsin-containing membranes to digest proteins online after a capillary electrophoresis (CE) separation and prior to tandem mass spectrometry. Proteolysis after the separation allows the peptides from a given protein to enter the mass spectrometer in a single plug. Thus, migration time can serve as an additional criterion for confirming the identification of a peptide. The membrane resides in a sheath-flow electrospray ionization (ESI) source to enable digestion immediately before spray into the mass spectrometer, thus limiting separation of the digested peptides. Using the same membrane, digestion occurred reproducibly during 20 consecutive CE analyses performed over a 10 h period. Additionally, after separating a mixture of six unreduced proteins with CE, online digestion facilitated protein identification with at least 2 identifiable peptides for all the proteins. Sequence coverages were >75% for myoglobin and carbonic anhydrase II but much lower for proteins containing disulfide bonds. Development of methods for efficient separation of reduced proteins or identification of cross-linked peptides should enhance sequence coverages for proteins with disulfide bonds. Migration times for the peptides identified from a specific protein differed by <∼30 s, which allows for rejection of some spurious peptide identifications.
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Affiliation(s)
- Kendall A Ryan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
| | - Merlin L Bruening
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA. .,Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
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5
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Zhang W, Xiang Y, Xu W. Probing protein higher-order structures by native capillary electrophoresis-mass spectrometry. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Han M, Smith R, Rock DA. Capillary Electrophoresis-Mass Spectrometry (CE-MS) by Sheath-Flow Nanospray Interface and Its Use in Biopharmaceutical Applications. Methods Mol Biol 2022; 2531:15-47. [PMID: 35941476 DOI: 10.1007/978-1-0716-2493-7_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Both capillary electrophoresis (CE) and mass spectrometry (MS) technologies are powerful analytical tools that have been used extensively in the characterization of biologics in the biopharmaceutical industry. The direct coupling of CE with MS is an attractive approach, in that the high separation capability of CE and the ultrasensitive detection and accurate identification performance of MS can be combined to provide a powerful system for the analysis of complex analytes. In this chapter, we discuss the detailed procedure of carrying out CE-MS analysis using a nano sheath-flow interface and its applications including intact mass analysis of monoclonal antibodies and fusion proteins, and a biotransformation study of two Fc-FGF21 molecules in a single-dose pharmacokinetic mice study. Optimization processes, including the finetuning of CE conditions and MS parameters, are illustrated in this chapter, with focuses on method robustness and assay reproducibility.
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Affiliation(s)
- Mei Han
- Pharmacokinetics and Drug Metabolism, Amgen Research, Amgen Inc., South San Francisco, CA, USA.
| | - Richard Smith
- Pharmacokinetics and Drug Metabolism, Amgen Research, Amgen Inc., South San Francisco, CA, USA
| | - Dan A Rock
- Pharmacokinetics and Drug Metabolism, Amgen Research, Amgen Inc., South San Francisco, CA, USA
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Kuzyk VO, Somsen GW, Haselberg R. CE-MS for Proteomics and Intact Protein Analysis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1336:51-86. [PMID: 34628627 DOI: 10.1007/978-3-030-77252-9_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
This chapter aims to explore various parameters involved in achieving high-end capillary electrophoresis hyphenated to mass spectrometry (CE-MS) analysis of proteins, peptides, and their posttranslational modifications. The structure of the topics discussed in this book chapter is conveniently mapped on the scheme of the CE-MS system itself, starting from sample preconcentration and injection techniques and finishing with mass analyzer considerations. After going through the technical considerations, a variety of relevant applications for this analytical approach are presented, including posttranslational modifications analysis, clinical biomarker discovery, and its growing use in the biotechnological industry.
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Affiliation(s)
- Valeriia O Kuzyk
- Division of Bioanalytical Chemistry, AIMMS: Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Govert W Somsen
- Division of Bioanalytical Chemistry, AIMMS: Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Rob Haselberg
- Division of Bioanalytical Chemistry, AIMMS: Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
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8
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Kumar R, Guttman A, Rathore AS. Applications of capillary electrophoresis for biopharmaceutical product characterization. Electrophoresis 2021; 43:143-166. [PMID: 34591322 DOI: 10.1002/elps.202100182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/07/2021] [Accepted: 09/23/2021] [Indexed: 12/16/2022]
Abstract
Capillary electrophoresis (CE), after being introduced several decades ago, has carved out a niche for itself in the field of analytical characterization of biopharmaceutical products. It does not only offer fast separation, high resolution in miniaturized format, but equally importantly represents an orthogonal separation mechanism to high-performance liquid chromatography. Therefore, it is not surprising that CE-based methods can be found in all major pharmacopoeias and are recommended for the analysis of biopharmaceutical products during process development, characterization, quality control, and release testing. Different separation formats of CE, such as capillary gel electrophoresis, capillary isoelectric focusing, and capillary zone electrophoresis are widely used for size and charge heterogeneity characterization as well as purity and stability testing of therapeutic proteins. Hyphenation of CE with MS is emerging as a promising bioanalytical tool to assess the primary structure of therapeutic proteins along with any impurities. In this review, we confer the latest developments in capillary electrophoresis, used for the characterization of critical quality attributes of biopharmaceutical products covering the past 6 years (2015-2021). Monoclonal antibodies, due to their significant share in the market, have been given prioritized coverage.
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Affiliation(s)
- Ramesh Kumar
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Andras Guttman
- Horváth Csaba Memorial Laboratories of Bioseparation Sciences, Research Center for Molecular Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,Translational Glycomics Group, Research Institute of Biomolecular and Chemical Engineering, University of Pannonia, Veszprem, Hungary
| | - Anurag S Rathore
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
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9
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Kulyk DS, Amoah E, Badu-Tawiah AK. High-Throughput Mass Spectrometry Screening Platform for Discovering New Chemical Reactions under Uncatalyzed, Solvent-Free Experimental Conditions. Anal Chem 2020; 92:15025-15033. [PMID: 33151666 DOI: 10.1021/acs.analchem.0c02960] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A gas-phase high-throughput reaction screening platform was developed for the first time to study chemical structures of closely related functional groups and for the discovery of novel organic reaction pathways. Experiments were performed using the contained atmospheric pressure chemical ionization (APCI) source that enabled nonthermal, nonequilibrium plasma chemistry to be monitored by mass spectrometry (MS) in real time. This contained-APCI MS platform allowed an array of reagents to be tested, resulting in the studies of multiple gas-phase reactions in parallel. By exposing headspace vapor of the selected reagents to corona discharge, solvent-free Borsche-Drecsel cyclization reaction, Katritzky chemistry, and Paal-Knorr pyrrole synthesis were examined in the gas phase, outside the high vacuum environment of the mass spectrometer. A new radical-mediated hydrazine coupling reaction was also discovered, which provided a selective pathway to synthesize secondary amines without using a catalyst. The mechanisms of these atmospheric pressure gas-phase reactions were explored through the direct capture of intermediates and via comparison with the corresponding bulk solution and droplet-phase reactions.
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Affiliation(s)
- Dmytro S Kulyk
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Enoch Amoah
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Abraham K Badu-Tawiah
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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10
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Fornelli L, Srzentić K, Toby TK, Doubleday PF, Huguet R, Mullen C, Melani RD, Dos Santos Seckler H, DeHart CJ, Weisbrod CR, Durbin KR, Greer JB, Early BP, Fellers RT, Zabrouskov V, Thomas PM, Compton PD, Kelleher NL. Thorough Performance Evaluation of 213 nm Ultraviolet Photodissociation for Top-down Proteomics. Mol Cell Proteomics 2020; 19:405-420. [PMID: 31888965 PMCID: PMC7000117 DOI: 10.1074/mcp.tir119.001638] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 11/29/2019] [Indexed: 11/06/2022] Open
Abstract
Top-down proteomics studies intact proteoform mixtures and offers important advantages over more common bottom-up proteomics technologies, as it avoids the protein inference problem. However, achieving complete molecular characterization of investigated proteoforms using existing technologies remains a fundamental challenge for top-down proteomics. Here, we benchmark the performance of ultraviolet photodissociation (UVPD) using 213 nm photons generated by a solid-state laser applied to the study of intact proteoforms from three organisms. Notably, the described UVPD setup applies multiple laser pulses to induce ion dissociation, and this feature can be used to optimize the fragmentation outcome based on the molecular weight of the analyzed biomolecule. When applied to complex proteoform mixtures in high-throughput top-down proteomics, 213 nm UVPD demonstrated a high degree of complementarity with the most employed fragmentation method in proteomics studies, higher-energy collisional dissociation (HCD). UVPD at 213 nm offered higher average proteoform sequence coverage and degree of proteoform characterization (including localization of post-translational modifications) than HCD. However, previous studies have shown limitations in applying database search strategies developed for HCD fragmentation to UVPD spectra which contains up to nine fragment ion types. We therefore performed an analysis of the different UVPD product ion type frequencies. From these data, we developed an ad hoc fragment matching strategy and determined the influence of each possible ion type on search outcomes. By paring down the number of ion types considered in high-throughput UVPD searches from all types down to the four most abundant, we were ultimately able to achieve deeper proteome characterization with UVPD. Lastly, our detailed product ion analysis also revealed UVPD cleavage propensities and determined the presence of a product ion produced specifically by 213 nm photons. All together, these observations could be used to better elucidate UVPD dissociation mechanisms and improve the utility of the technique for proteomic applications.
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Affiliation(s)
- Luca Fornelli
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Kristina Srzentić
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Timothy K Toby
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Peter F Doubleday
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Romain Huguet
- Thermo Fisher Scientific, San Jose, California 95134
| | | | - Rafael D Melani
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Henrique Dos Santos Seckler
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Caroline J DeHart
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | | | - Kenneth R Durbin
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208; Proteinaceous Inc., Evanston, Illinois 60201
| | - Joseph B Greer
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Bryan P Early
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Ryan T Fellers
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | | | - Paul M Thomas
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Philip D Compton
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208
| | - Neil L Kelleher
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208.
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11
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McCool EN, Lodge JM, Basharat AR, Liu X, Coon JJ, Sun L. Capillary Zone Electrophoresis-Tandem Mass Spectrometry with Activated Ion Electron Transfer Dissociation for Large-scale Top-down Proteomics. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:2470-2479. [PMID: 31073891 PMCID: PMC6527361 DOI: 10.1007/s13361-019-02206-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 05/21/2023]
Abstract
Capillary zone electrophoresis (CZE)-tandem mass spectrometry (MS/MS) has been recognized as an efficient approach for top-down proteomics recently for its high-capacity separation and highly sensitive detection of proteoforms. However, the commonly used collision-based dissociation methods often cannot provide extensive fragmentation of proteoforms for thorough characterization. Activated ion electron transfer dissociation (AI-ETD), that combines infrared photoactivation concurrent with ETD, has shown better performance for proteoform fragmentation than higher energy-collisional dissociation (HCD) and standard ETD. Here, we present the first application of CZE-AI-ETD on an Orbitrap Fusion Lumos mass spectrometer for large-scale top-down proteomics of Escherichia coli (E. coli) cells. CZE-AI-ETD outperformed CZE-ETD regarding proteoform and protein identifications (IDs). CZE-AI-ETD reached comparable proteoform and protein IDs with CZE-HCD. CZE-AI-ETD tended to generate better expectation values (E values) of proteoforms than CZE-HCD and CZE-ETD, indicating a higher quality of MS/MS spectra from AI-ETD respecting the number of sequence-informative fragment ions generated. CZE-AI-ETD showed great reproducibility regarding the proteoform and protein IDs with relative standard deviations less than 4% and 2% (n = 3). Coupling size exclusion chromatography (SEC) to CZE-AI-ETD identified 3028 proteoforms and 387 proteins from E. coli cells with 1% spectrum level and 5% proteoform-level false discovery rates. The data represents the largest top-down proteomics dataset using the AI-ETD method so far. Single-shot CZE-AI-ETD of one SEC fraction identified 957 proteoforms and 253 proteins. N-terminal truncations, signal peptide cleavage, N-terminal methionine removal, and various post-translational modifications including protein N-terminal acetylation, methylation, S-thiolation, disulfide bonds, and lysine succinylation were detected.
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Affiliation(s)
- Elijah N McCool
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, MI, 48824, USA
| | - Jean M Lodge
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Abdul Rehman Basharat
- Department of BioHealth Informatics, Indiana University-Purdue University Indianapolis, 719 Avenue, Indianapolis, IN, 46202, USA
| | - Xiaowen Liu
- Department of BioHealth Informatics, Indiana University-Purdue University Indianapolis, 719 Avenue, Indianapolis, IN, 46202, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, 410 West 10th Street, Indianapolis, IN, 46202, USA
| | - Joshua J Coon
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, MI, 48824, USA.
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Gomes FP, Yates JR. Recent trends of capillary electrophoresis-mass spectrometry in proteomics research. MASS SPECTROMETRY REVIEWS 2019; 38:445-460. [PMID: 31407381 PMCID: PMC6800771 DOI: 10.1002/mas.21599] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Progress in proteomics research has led to a demand for powerful analytical tools with high separation efficiency and sensitivity for confident identification and quantification of proteins, posttranslational modifications, and protein complexes expressed in cells and tissues. This demand has significantly increased interest in capillary electrophoresis-mass spectrometry (CE-MS) in the past few years. This review provides highlights of recent advances in CE-MS for proteomics research, including a short introduction to top-down mass spectrometry and native mass spectrometry (native MS), as well as a detailed overview of CE methods. Both the potential and limitations of these methods for the analysis of proteins and peptides in synthetic and biological samples and the challenges of CE methods are discussed, along with perspectives about the future direction of CE-MS. @ 2019 Wiley Periodicals, Inc. Mass Spec Rev 00:1-16, 2019.
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Affiliation(s)
| | - John R. Yates
- Correspondent author: , Phone number: (858) 784-8862, Departments of Molecular Medicine and Neurobiology, 10550 North Torrey Pines Road, SR302B, The Scripps Research Institute, La Jolla, CA 92037
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13
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Shen X, Yang Z, McCool EN, Lubeckyj RA, Chen D, Sun L. Capillary zone electrophoresis-mass spectrometry for top-down proteomics. Trends Analyt Chem 2019; 120:115644. [PMID: 31537953 PMCID: PMC6752746 DOI: 10.1016/j.trac.2019.115644] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mass spectrometry (MS)-based top-down proteomics characterizes complex proteomes at the intact proteoform level and provides an accurate picture of protein isoforms and protein post-translational modifications in the cell. The progress of top-down proteomics requires novel analytical tools with high peak capacity for proteoform separation and high sensitivity for proteoform detection. The requirements have made capillary zone electrophoresis (CZE)-MS an attractive approach for advancing large-scale top-down proteomics. CZE has achieved a peak capacity of 300 for separation of complex proteoform mixtures. CZE-MS has shown drastically better sensitivity than commonly used reversed-phase liquid chromatography (RPLC)-MS for proteoform detection. The advanced CZE-MS identified 6,000 proteoforms of nearly 1,000 proteoform families from a complex proteome sample, which represents one of the largest top-down proteomic datasets so far. In this review, we focus on the recent progress in CZE-MS-based top-down proteomics and provide our perspectives about its future directions.
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Affiliation(s)
- Xiaojing Shen
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
| | - Zhichang Yang
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
| | - Elijah N. McCool
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
| | - Rachele A. Lubeckyj
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
| | - Daoyang Chen
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, 578 S Shaw Lane, East Lansing, Michigan 48824, United States
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14
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Capturing site-specific heterogeneity with large-scale N-glycoproteome analysis. Nat Commun 2019; 10:1311. [PMID: 30899004 PMCID: PMC6428843 DOI: 10.1038/s41467-019-09222-w] [Citation(s) in RCA: 158] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 02/19/2019] [Indexed: 11/08/2022] Open
Abstract
Protein glycosylation is a highly important, yet poorly understood protein post-translational modification. Thousands of possible glycan structures and compositions create potential for tremendous site heterogeneity. A lack of suitable analytical methods for large-scale analyses of intact glycopeptides has limited our abilities both to address the degree of heterogeneity across the glycoproteome and to understand how this contributes biologically to complex systems. Here we show that N-glycoproteome site-specific microheterogeneity can be captured via large-scale glycopeptide profiling methods enabled by activated ion electron transfer dissociation (AI-ETD), ultimately characterizing 1,545 N-glycosites (>5,600 unique N-glycopeptides) from mouse brain tissue. Our data reveal that N-glycosylation profiles can differ between subcellular regions and structural domains and that N-glycosite heterogeneity manifests in several different forms, including dramatic differences in glycosites on the same protein. Moreover, we use this large-scale glycoproteomic dataset to develop several visualizations that will prove useful for analyzing intact glycopeptides in future studies. Mass spectrometry facilitates large-scale glycosylation profiling but in-depth analysis of intact glycopeptides is still challenging. Here, the authors show that activated ion electron transfer dissociation is suitable for glycopeptide fragmentation and improves glycoproteome coverage.
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15
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Pandeswari PB, Sabareesh V. Middle-down approach: a choice to sequence and characterize proteins/proteomes by mass spectrometry. RSC Adv 2018; 9:313-344. [PMID: 35521579 PMCID: PMC9059502 DOI: 10.1039/c8ra07200k] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 12/11/2018] [Indexed: 12/27/2022] Open
Abstract
Owing to rapid growth in the elucidation of genome sequences of various organisms, deducing proteome sequences has become imperative, in order to have an improved understanding of biological processes. Since the traditional Edman method was unsuitable for high-throughput sequencing and also for N-terminus modified proteins, mass spectrometry (MS) based methods, mainly based on soft ionization modes: electrospray ionization and matrix-assisted laser desorption/ionization, began to gain significance. MS based methods were adaptable for high-throughput studies and applicable for sequencing N-terminus blocked proteins/peptides too. Consequently, over the last decade a new discipline called 'proteomics' has emerged, which encompasses the attributes necessary for high-throughput identification of proteins. 'Proteomics' may also be regarded as an offshoot of the classic field, 'biochemistry'. Many protein sequencing and proteomic investigations were successfully accomplished through MS dependent sequence elucidation of 'short proteolytic peptides (typically: 7-20 amino acid residues), which is called the 'shotgun' or 'bottom-up (BU)' approach. While the BU approach continues as a workhorse for proteomics/protein sequencing, attempts to sequence intact proteins without proteolysis, called the 'top-down (TD)' approach started, due to ambiguities in the BU approach, e.g., protein inference problem, identification of proteoforms and the discovery of posttranslational modifications (PTMs). The high-throughput TD approach (TD proteomics) is yet in its infancy. Nevertheless, TD characterization of purified intact proteins has been useful for detecting PTMs. With the hope to overcome the pitfalls of BU and TD strategies, another concept called the 'middle-down (MD)' approach was put forward. Similar to BU, the MD approach also involves proteolysis, but in a restricted manner, to produce 'longer' proteolytic peptides than the ones usually obtained in BU studies, thereby providing better sequence coverage. In this regard, special proteases (OmpT, Sap9, IdeS) have been used, which can cleave proteins to produce longer proteolytic peptides. By reviewing ample evidences currently existing in the literature that is predominantly on PTM characterization of histones and antibodies, herein we highlight salient features of the MD approach. Consequently, we are inclined to claim that the MD concept might have widespread applications in future for various research areas, such as clinical, biopharmaceuticals (including PTM analysis) and even for general/routine characterization of proteins including therapeutic proteins, but not just limited to analysis of histones or antibodies.
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Affiliation(s)
- P Boomathi Pandeswari
- Advanced Centre for Bio Separation Technology (CBST), Vellore Institute of Technology (VIT) Vellore Tamil Nadu 632014 India
| | - Varatharajan Sabareesh
- Advanced Centre for Bio Separation Technology (CBST), Vellore Institute of Technology (VIT) Vellore Tamil Nadu 632014 India
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16
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Dilillo M, de Graaf EL, Yadav A, Belov ME, McDonnell LA. Ultraviolet Photodissociation of ESI- and MALDI-Generated Protein Ions on a Q-Exactive Mass Spectrometer. J Proteome Res 2018; 18:557-564. [PMID: 30484663 DOI: 10.1021/acs.jproteome.8b00896] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The identification of molecular ions produced by MALDI or ESI strongly relies on their fragmentation to structurally informative fragments. The widely diffused fragmentation techniques for ESI multiply charged ions are either incompatible (ECD and ETD) or show lower efficiency (CID, HCD), with the predominantly singly charged peptide and protein ions formed by MALDI. In-source decay has been successfully adopted to sequence MALDI-generated ions, but it further increases spectral complexity, and it is not compatible with mass-spectrometry imaging. Excellent UVPD performances, in terms of number of fragment ions and sequence coverage, has been demonstrated for electrospray ionization for multiple proteomics applications. UVPD showed a much lower charge-state dependence, and so protein ions produced by MALDI may exhibit equal propensity to fragment. Here we report UVPD implementation on an Orbitrap Q-Exactive Plus mass spectrometer equipped with an ESI/EP-MALDI. UVPD of MALDI-generated ions was benchmarked against MALDI-ISD, MALDI-HCD, and ESI-UVPD. MALDI-UVPD outperformed MALDI-HCD and ISD, efficiently sequencing small proteins ions. Moreover, the singly charged nature of MALDI-UVPD avoids the bioinformatics challenges associated with highly congested ESI-UVPD mass spectra. Our results demonstrate the ability of UVPD to further improve tandem mass spectrometry capabilities for MALDI-generated protein ions. Data are available via ProteomeXchange with identifier PXD011526.
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Affiliation(s)
- Marialaura Dilillo
- Fondazione Pisana per la Scienza ONLUS , 56107 San Giuliano Terme, Pisa , Italy
| | - Erik L de Graaf
- Fondazione Pisana per la Scienza ONLUS , 56107 San Giuliano Terme, Pisa , Italy
| | - Avinash Yadav
- Fondazione Pisana per la Scienza ONLUS , 56107 San Giuliano Terme, Pisa , Italy.,Scuola Normale Superiore di Pisa , 56126 Pisa , Italy
| | - Mikhail E Belov
- Spectroglyph LLC , Kennewick , Washington 99338 , United States
| | - Liam A McDonnell
- Fondazione Pisana per la Scienza ONLUS , 56107 San Giuliano Terme, Pisa , Italy.,Center for Proteomics and Metabolomics , Leiden University Medical Center , 2333 ZA Leiden , The Netherlands
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17
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Štěpánová S, Kašička V. Recent developments and applications of capillary and microchip electrophoresis in proteomics and peptidomics (2015-mid 2018). J Sep Sci 2018; 42:398-414. [DOI: 10.1002/jssc.201801090] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/15/2018] [Accepted: 11/16/2018] [Indexed: 12/27/2022]
Affiliation(s)
- Sille Štěpánová
- Institute of Organic Chemistry and Biochemistry; The Czech Academy of Sciences; Prague 6 Czechia
| | - Václav Kašička
- Institute of Organic Chemistry and Biochemistry; The Czech Academy of Sciences; Prague 6 Czechia
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18
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Riley NM, Sikora JW, Seckler HS, Greer JB, Fellers RT, LeDuc RD, Westphall MS, Thomas PM, Kelleher NL, Coon JJ. The Value of Activated Ion Electron Transfer Dissociation for High-Throughput Top-Down Characterization of Intact Proteins. Anal Chem 2018; 90:8553-8560. [PMID: 29924586 DOI: 10.1021/acs.analchem.8b01638] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
High-throughput top-down proteomic experiments directly identify proteoforms in complex mixtures, making high quality tandem mass spectra necessary to deeply characterize proteins with many sources of variation. Collision-based dissociation methods offer expedient data acquisition but often fail to extensively fragment proteoforms for thorough analysis. Electron-driven dissociation methods are a popular alternative approach, especially for precursor ions with high charge density. Combining infrared photoactivation concurrent with electron transfer dissociation (ETD) reactions, i.e., activated ion ETD (AI-ETD), can significantly improve ETD characterization of intact proteins, but benefits of AI-ETD have yet to be quantified in high-throughput top-down proteomics. Here, we report the first application of AI-ETD to LC-MS/MS characterization of intact proteins (<20 kDa), highlighting improved proteoform identification the method offers over higher energy-collisional dissociation (HCD), standard ETD, and ETD followed by supplemental HCD activation (EThcD). We identified 935 proteoforms from 295 proteins from human colorectal cancer cell line HCT116 using AI-ETD compared to 1014 proteoforms, 915 proteoforms, and 871 proteoforms with HCD, ETD, and EThcD, respectively. Importantly, AI-ETD outperformed each of the three other methods in MS/MS success rates and spectral quality metrics (e.g., sequence coverage achieved and proteoform characterization scores). In all, this four-method analysis offers the most extensive comparisons to date and demonstrates that AI-ETD both increases identifications over other ETD methods and improves proteoform characterization via higher sequence coverage, positioning it as a premier method for high-throughput top-down proteomics.
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Affiliation(s)
| | - Jacek W Sikora
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | - Henrique S Seckler
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | - Joseph B Greer
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | - Ryan T Fellers
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | - Richard D LeDuc
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | | | - Paul M Thomas
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | - Neil L Kelleher
- National Resource for Translational and Developmental Proteomics, Departments of Chemistry and Molecular Biosciences , Northwestern University , Evanston , Illinois 60208 , United States
| | - Joshua J Coon
- Morgridge Institute for Research , Madison , Wisconsin 53706 , United States
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19
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Qian C, Wang S, Fu H, Turner RFB, Li H, Chen DDY. Pressure-assisted capillary electrophoresis frontal analysis for faster binding constant determination. Electrophoresis 2018; 39:1786-1793. [PMID: 29700847 DOI: 10.1002/elps.201800049] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/04/2018] [Accepted: 04/18/2018] [Indexed: 02/28/2024]
Abstract
Adding external pressure during the process of capillary electrophoresis usually add to the band broadening, especially if the pressure induced flow is significant. The resolution is normally negatively affected in pressure-assisted capillary electrophoresis (PACE). Frontal analysis (FA), however, can potentially benefit from using an external pressure while avoiding the drawbacks in other modes of CE. In this work, possible impact from the external pressure was simulated by COMSOL Multiphysics®. Under a typical CE-FA set-up, it was found that the detected concentrations of analyte will not be significantly affected by an external pressure less than 5 psi. Besides, the measured ligand concentration in PACE-FA was also not affected by common variables (molecular diffusion coefficient (10-8 to 10-11 m2 /s), capillary length etc). To provide an experimental proof, PACE-FA is used to study the binding interactions between hydroxypropyl β-cyclodextrin (HP-β-CD) and small ligand molecules. Taking the HP-β-CD /benzoate pair as an example, the binding constants determined by CE-FA (18.3 ± 0.8 M-1 ) and PACE-FA (16.5 ± 0.5 M-1 ) are found to be similar. Based on the experimental results, it is concluded that PACE-FA can reduce the time of binding analysis while maintaining the accuracy of the measurements.
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Affiliation(s)
- Cheng Qian
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - Su Wang
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Hengqing Fu
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing, P. R. China
| | - Robin F B Turner
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Huihui Li
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing, P. R. China
| | - David D Y Chen
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing, P. R. China
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20
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Gusenkov S, Stutz H. Top-down and bottom-up characterization of nitrated birch pollen allergen Bet v 1a with CZE hyphenated to an Orbitrap mass spectrometer. Electrophoresis 2018; 39:1190-1200. [PMID: 29389018 PMCID: PMC6175448 DOI: 10.1002/elps.201700413] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/19/2018] [Accepted: 01/19/2018] [Indexed: 11/19/2022]
Abstract
Tyrosine (Tyr) residues of the major pollen allergen of birch Betula verrucosa, Bet v 1a, were nitrated by peroxynitrite. This modification enhances the allergenicity. Modified tyrosines were identified by analyzing intact allergen variants in combination with top‐down and bottom‐up approaches. Therefore, a laboratory‐built sheath‐liquid assisted ESI interface was applied for hyphenation of CE to an Orbitrap mass spectrometer to localize individual nitration sites. The major focus was on identification of primary nitration sites. The top‐down approach unambiguously identified Tyr 5 as the most prominent modification site. Fragments from the allergen core and the C‐terminal part carried up to three potential nitration sites, respectively. Thus, a bottom‐up approach with tryptic digest was used as a complementary strategy which allowed for the unambiguous localization of nitration sites within the respective peptides. Nitration propensity for individual Tyr residues was addressed by comparison of MS signals of nitrated peptides relative to all cognates of homolog primary sequence. Combined data identified surface exposed Tyr 5 and Tyr 66 as major nitration sites followed by less accessible Tyr 158 whereas Tyr 81, 83 and 150 possess a lower nitration tendency and are apparently modified in variants with higher nitration levels.
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Affiliation(s)
- Sergey Gusenkov
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Hanno Stutz
- Department of Biosciences, University of Salzburg, Salzburg, Austria
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21
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Affiliation(s)
- Bifan Chen
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Kyle A. Brown
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Ziqing Lin
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Human Proteomics Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Human Proteomics Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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22
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Affiliation(s)
- Nicholas
M. Riley
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Genome
Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Joshua J. Coon
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Genome
Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department
of Biomolecular Chemistry, University of
Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Morgridge
Institute for Research, Madison, Wisconsin 53715, United States
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23
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Pettit ME, Brantley MR, Donnarumma F, Murray KK, Solouki T. Broadband ion mobility deconvolution for rapid analysis of complex mixtures. Analyst 2018; 143:2574-2586. [DOI: 10.1039/c8an00193f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Broadband IM-MS deconvolution allows generation of IM and MS data for species that are UPLC-IM-MS unresolved.
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Affiliation(s)
| | | | | | | | - Touradj Solouki
- Department of Chemistry and Biochemistry
- Baylor University
- Waco
- USA
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24
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Riley NM, Westphall MS, Coon JJ. Sequencing Larger Intact Proteins (30-70 kDa) with Activated Ion Electron Transfer Dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:140-149. [PMID: 29027149 PMCID: PMC5786479 DOI: 10.1007/s13361-017-1808-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/31/2017] [Accepted: 09/02/2017] [Indexed: 05/12/2023]
Abstract
The analysis of intact proteins via mass spectrometry can offer several benefits to proteome characterization, although the majority of top-down experiments focus on proteoforms in a relatively low mass range (<30 kDa). Recent studies have focused on improving the analysis of larger intact proteins (up to ~75 kDa), but they have also highlighted several challenges to be addressed. One major hurdle is the efficient dissociation of larger protein ions, which often to do not yield extensive fragmentation via conventional tandem MS methods. Here we describe the first application of activated ion electron transfer dissociation (AI-ETD) to proteins in the 30-70 kDa range. AI-ETD leverages infrared photo-activation concurrent to ETD reactions to improve sequence-informative product ion generation. This method generates more product ions and greater sequence coverage than conventional ETD, higher-energy collisional dissociation (HCD), and ETD combined with supplemental HCD activation (EThcD). Importantly, AI-ETD provides the most thorough protein characterization for every precursor ion charge state investigated in this study, making it suitable as a universal fragmentation method in top-down experiments. Additionally, we highlight several acquisition strategies that can benefit characterization of larger proteins with AI-ETD, including combination of spectra from multiple ETD reaction times for a given precursor ion, multiple spectral acquisitions of the same precursor ion, and combination of spectra from two different dissociation methods (e.g., AI-ETD and HCD). In all, AI-ETD shows great promise as a method for dissociating larger intact protein ions as top-down proteomics continues to advance into larger mass ranges. Graphical Abstract ᅟ.
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Affiliation(s)
- Nicholas M Riley
- Genome Center of Wisconsin, Madison, WI, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | | | - Joshua J Coon
- Genome Center of Wisconsin, Madison, WI, USA.
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
- Morgridge Institute for Research, Madison, WI, USA.
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25
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Kašička V. Recent developments in capillary and microchip electroseparations of peptides (2015-mid 2017). Electrophoresis 2017; 39:209-234. [PMID: 28836681 DOI: 10.1002/elps.201700295] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 08/15/2017] [Accepted: 08/16/2017] [Indexed: 12/17/2022]
Abstract
The review brings a comprehensive overview of recent developments and applications of high performance capillary and microchip electroseparation methods (zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography, and electrochromatography) to analysis, microscale isolation, purification, and physicochemical and biochemical characterization of peptides in the years 2015, 2016, and ca. up to the middle of 2017. Advances in the investigation of electromigration properties of peptides and in the methodology of their analysis (sample preseparation, preconcentration and derivatization, adsorption suppression and EOF control, and detection) are described. New developments in particular CE and CEC methods are presented and several types of their applications to peptide analysis are reported: qualitative and quantitative analysis, determination in complex (bio)matrices, monitoring of chemical and enzymatical reactions and physical changes, amino acid, sequence and chiral analysis, and peptide mapping of proteins. Some micropreparative peptide separations are shown and capabilities of CE and CEC methods to provide important physicochemical characteristics of peptides are demonstrated.
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Affiliation(s)
- Václav Kašička
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
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26
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Weisbrod CR, Kaiser NK, Syka JEP, Early L, Mullen C, Dunyach JJ, English AM, Anderson LC, Blakney GT, Shabanowitz J, Hendrickson CL, Marshall AG, Hunt DF. Front-End Electron Transfer Dissociation Coupled to a 21 Tesla FT-ICR Mass Spectrometer for Intact Protein Sequence Analysis. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1787-1795. [PMID: 28721671 PMCID: PMC5711562 DOI: 10.1007/s13361-017-1702-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/21/2017] [Accepted: 04/29/2017] [Indexed: 05/13/2023]
Abstract
High resolution mass spectrometry is a key technology for in-depth protein characterization. High-field Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) enables high-level interrogation of intact proteins in the most detail to date. However, an appropriate complement of fragmentation technologies must be paired with FTMS to provide comprehensive sequence coverage, as well as characterization of sequence variants, and post-translational modifications. Here we describe the integration of front-end electron transfer dissociation (FETD) with a custom-built 21 tesla FT-ICR mass spectrometer, which yields unprecedented sequence coverage for proteins ranging from 2.8 to 29 kDa, without the need for extensive spectral averaging (e.g., ~60% sequence coverage for apo-myoglobin with four averaged acquisitions). The system is equipped with a multipole storage device separate from the ETD reaction device, which allows accumulation of multiple ETD fragment ion fills. Consequently, an optimally large product ion population is accumulated prior to transfer to the ICR cell for mass analysis, which improves mass spectral signal-to-noise ratio, dynamic range, and scan rate. We find a linear relationship between protein molecular weight and minimum number of ETD reaction fills to achieve optimum sequence coverage, thereby enabling more efficient use of instrument data acquisition time. Finally, real-time scaling of the number of ETD reactions fills during method-based acquisition is shown, and the implications for LC-MS/MS top-down analysis are discussed. Graphical Abstract ᅟ.
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Affiliation(s)
- Chad R Weisbrod
- National High Magnetic Field Laboratory (NHMFL), 1800 East Paul Dirac Dr., Tallahassee, FL, 32310, USA.
| | - Nathan K Kaiser
- National High Magnetic Field Laboratory (NHMFL), 1800 East Paul Dirac Dr., Tallahassee, FL, 32310, USA
| | | | - Lee Early
- Thermo Fisher Scientific, San Jose, CA, 95134, USA
| | | | | | - A Michelle English
- Department of Chemistry, University of Virginia, McCormick Road, P.O. Box 400319, Charlottesville, VA, 22904-4319, USA
| | - Lissa C Anderson
- National High Magnetic Field Laboratory (NHMFL), 1800 East Paul Dirac Dr., Tallahassee, FL, 32310, USA
| | - Greg T Blakney
- National High Magnetic Field Laboratory (NHMFL), 1800 East Paul Dirac Dr., Tallahassee, FL, 32310, USA
| | - Jeffrey Shabanowitz
- Department of Chemistry, University of Virginia, McCormick Road, P.O. Box 400319, Charlottesville, VA, 22904-4319, USA
| | - Christopher L Hendrickson
- National High Magnetic Field Laboratory (NHMFL), 1800 East Paul Dirac Dr., Tallahassee, FL, 32310, USA
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, FL, 32306, USA
| | - Alan G Marshall
- National High Magnetic Field Laboratory (NHMFL), 1800 East Paul Dirac Dr., Tallahassee, FL, 32310, USA
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, FL, 32306, USA
| | - Donald F Hunt
- Department of Chemistry, University of Virginia, McCormick Road, P.O. Box 400319, Charlottesville, VA, 22904-4319, USA
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
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27
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Riley NM, Hebert AS, Dürnberger G, Stanek F, Mechtler K, Westphall MS, Coon JJ. Phosphoproteomics with Activated Ion Electron Transfer Dissociation. Anal Chem 2017; 89:6367-6376. [PMID: 28383256 PMCID: PMC5555596 DOI: 10.1021/acs.analchem.7b00212] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The ability to localize phosphosites to specific amino acid residues is crucial to translating phosphoproteomic data into biological meaningful contexts. In a companion manuscript ( Anal. Chem. 2017 , DOI: 10.1021/acs.analchem.7b00213 ), we described a new implementation of activated ion electron transfer dissociation (AI-ETD) on a quadrupole-Orbitrap-linear ion trap hybrid MS system (Orbitrap Fusion Lumos), which greatly improved peptide fragmentation and identification over ETD and other supplemental activation methods. Here we present the performance of AI-ETD for identifying and localizing sites of phosphorylation in both phosphopeptides and intact phosphoproteins. Using 90 min analyses we show that AI-ETD can identify 24,503 localized phosphopeptide spectral matches enriched from mouse brain lysates, which more than triples identifications from standard ETD experiments and outperforms ETcaD and EThcD as well. AI-ETD achieves these gains through improved quality of fragmentation and MS/MS success rates for all precursor charge states, especially for doubly protonated species. We also evaluate the degree to which phosphate neutral loss occurs from phosphopeptide product ions due to the infrared photoactivation of AI-ETD and show that modifying phosphoRS (a phosphosite localization algorithm) to include phosphate neutral losses can significantly improve localization in AI-ETD spectra. Finally, we demonstrate the utility of AI-ETD in localizing phosphosites in α-casein, an ∼23.5 kDa phosphoprotein that showed eight of nine known phosphorylation sites occupied upon intact mass analysis. AI-ETD provided the greatest sequence coverage for all five charge states investigated and was the only fragmentation method to localize all eight phosphosites for each precursor. Overall, this work highlights the analytical value AI-ETD can bring to both bottom-up and top-down phosphoproteomics.
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Affiliation(s)
- Nicholas M. Riley
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Alexander S. Hebert
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Gerhard Dürnberger
- Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, A-1030 Vienna, Austria
- GMI, Gregor Mendel Institute of Molecular Plant Biology, Dr. Bohr Gasse 3, A-1030 Vienna, Austria
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr Gasse 3, A-1030 Vienna, Austria
| | - Florian Stanek
- Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, A-1030 Vienna, Austria
| | - Karl Mechtler
- Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, A-1030 Vienna, Austria
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr Gasse 3, A-1030 Vienna, Austria
| | - Michael S. Westphall
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Joshua J. Coon
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Morgridge Institute for Research, Madison, Wisconsin, USA
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28
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Biacchi M, Said N, Beck A, Leize-Wagner E, François YN. Top-down and middle-down approach by fraction collection enrichment using off-line capillary electrophoresis – mass spectrometry coupling: Application to monoclonal antibody F c/2 charge variants. J Chromatogr A 2017; 1498:120-127. [DOI: 10.1016/j.chroma.2017.02.064] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 01/13/2017] [Accepted: 02/26/2017] [Indexed: 12/22/2022]
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29
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Choi SB, Zamarbide M, Manzini MC, Nemes P. Tapered-Tip Capillary Electrophoresis Nano-Electrospray Ionization Mass Spectrometry for Ultrasensitive Proteomics: the Mouse Cortex. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:597-607. [PMID: 27853976 DOI: 10.1007/s13361-016-1532-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/16/2016] [Accepted: 10/18/2016] [Indexed: 06/06/2023]
Abstract
Ultrasensitive characterization of the proteome raises the potential to understand how differential gene expression orchestrates cell heterogeneity in the brain. Here, we report a microanalytical capillary electrophoresis nano-flow electrospray ionization (CE-nanoESI) interface for mass spectrometry to enable the measurement of limited amounts of proteins in the mouse cortex. Our design integrates a custom-built CE system to a tapered-tip metal emitter in a co-axial sheath-flow configuration. This interface can be constructed in <15 min using readily available components, facilitating broad adaptation. Tapered-tip CE-nanoESI generates stable electrospray by reproducibly anchoring the Taylor cone, minimizes sample dilution in the ion source, and ensures efficient ion generation by sustaining the cone-jet spraying regime. Parallel reaction monitoring provided a 260-zmol lower limit of detection for angiotensin II (156,000 copies). CE was able to resolve a complex mixture of peptides in ~330,000 theoretical plates and identify ~15 amol (~1 pg) of BSA or cytochrome c. Over 30 min of separation, 1 ng protein digest from the mouse cortex yielded 217 nonredundant proteins encompassing a ~3-log-order concentration range using a quadrupole time-of-flight mass spectrometer. Identified proteins included many products from genes that are traditionally used to mark oligodendrocytes, astrocytes, and microglia. Finally, key proteins involved in neurodegenerative disorders were detected (e.g., parkinsonism and spastic paraplegia). CE-nanoESI-HRMS delivers sufficient sensitivity to detect proteins in limited amounts of tissues and cell populations to help understand how gene expression differences maintain cell heterogeneity in the brain. Graphical Abstract ᅟ.
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Affiliation(s)
- Sam B Choi
- Department of Chemistry, The George Washington University, Washington, DC, 20052, USA
| | - Marta Zamarbide
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC, 20037, USA
| | - M Chiara Manzini
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC, 20037, USA
| | - Peter Nemes
- Department of Chemistry, The George Washington University, Washington, DC, 20052, USA.
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30
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Evaluation of a commercial electro-kinetically pumped sheath-flow nanospray interface coupled to an automated capillary zone electrophoresis system. Anal Bioanal Chem 2016; 409:1789-1795. [PMID: 27981343 DOI: 10.1007/s00216-016-0122-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/10/2016] [Accepted: 11/28/2016] [Indexed: 10/20/2022]
Abstract
Capillary zone electrophoresis-electrospray ionization-mass spectrometry (CZE-ESI-MS) is attracting renewed attention for proteomic and metabolomic analysis. An important reason for this interest is the maturation and commercialization of interfaces for coupling CZE with ESI-MS. One of these interfaces is an electro-kinetically pumped sheath flow nanospray interface developed by the Dovichi group, in which a very low sheath flow is generated based on electroosmosis within a glass emitter. CMP Scientific has commercialized this interface as the EMASS-II ion source. In this work, we compared the performance of the EMASS-II ion source with our in-house system. The performance of the systems is equivalent. We also coupled the EMASS-II ion source with a PrinCE Next|480 capillary electrophoresis autosampler and an Orbitrap mass spectrometer, and analyzed this system's performance in terms of sensitivity, reproducibility, and separation performance for separation of tryptic digests, intact proteins, and amino acids. The system produced reproducible analysis of BSA digest; the RSDs of peptide intensity and migration time across 24 runs were less than 20 and 6%, respectively. The system produced a linear calibration curve of intensity across a 30-fold range of tryptic digest concentration. The combination of a commercial autosampler and electrospray interface efficiently separated amino acids, peptides, and intact proteins, and only required 5 μL of sample for analysis. Graphical Abstract The commercial and locally constructed versions of the interface provide similar numbers of protein identifications from a Xenopus laevis fertilized egg digest.
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31
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Týčová A, Ledvina V, Klepárník K. Recent advances in CE-MS coupling: Instrumentation, methodology, and applications. Electrophoresis 2016; 38:115-134. [DOI: 10.1002/elps.201600366] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 08/30/2016] [Accepted: 08/30/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Anna Týčová
- Institute of Analytical Chemistry; Czech Academy of Sciences; Brno Czech Republic
| | - Vojtěch Ledvina
- Institute of Analytical Chemistry; Czech Academy of Sciences; Brno Czech Republic
| | - Karel Klepárník
- Institute of Analytical Chemistry; Czech Academy of Sciences; Brno Czech Republic
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32
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Zhao Y, Sun L, Zhu G, Dovichi NJ. Coupling Capillary Zone Electrophoresis to a Q Exactive HF Mass Spectrometer for Top-down Proteomics: 580 Proteoform Identifications from Yeast. J Proteome Res 2016; 15:3679-3685. [PMID: 27490796 DOI: 10.1021/acs.jproteome.6b00493] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We used reversed-phase liquid chromatography to separate the yeast proteome into 23 fractions. These fractions were then analyzed using capillary zone electrophoresis (CZE) coupled to a Q-Exactive HF mass spectrometer using an electrokinetically pumped sheath flow interface. The parameters of the mass spectrometer were first optimized for top-down proteomics using a mixture of seven model proteins; we observed that intact protein mode with a trapping pressure of 0.2 and normalized collision energy of 20% produced the highest intact protein signals and most protein identifications. Then, we applied the optimized parameters for analysis of the fractionated yeast proteome. From this, 580 proteoforms and 180 protein groups were identified via database searching of the MS/MS spectra. This number of proteoform identifications is two times larger than that of previous CZE-MS/MS studies. An additional 3,243 protein species were detected based on the parent ion spectra. Post-translational modifications including N-terminal acetylation, signal peptide removal, and oxidation were identified.
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Affiliation(s)
- Yimeng Zhao
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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33
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Zhu G, Sun L, Dovichi NJ. Dynamic pH junction preconcentration in capillary electrophoresis- electrospray ionization-mass spectrometry for proteomics analysis. Analyst 2016; 141:5216-20. [PMID: 27460877 DOI: 10.1039/c6an01140c] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Capillary zone electrophoresis (CZE)-electrospray ionization (ESI)-mass spectrometry (MS) is an interesting complimentary technique to reversed phase liquid chromatography (RPLC)-ESI-MS for proteomics research. However, the low sample loading capacity of CZE (typically a few nL) can limit its application for large-scale proteomics. A number of on-line sample preconcentration methods have been developed to increase sample loading volumes. This review considers the dynamic pH junction as a simple on-line sample preconcentration method; this method is well suited for amphiprotic analytes. In the pH junction, these analytes are suspended in a basic buffer, injected by pressure into the capillary, and separated in an acidic background electrolyte, with no changes in either CZE-MS operations or instrumentation. We have demonstrated that the dynamic pH junction method can improve the sample loading volume to sub-μL volumes without significant loss of separation capacity for bottom-up proteomic analysis. The dynamic pH junction based CZE-ESI-MS system has been applied for a number of complex biological samples, including the E. coli proteome, impurities in recombinant antibody therapeutics, and the characterization of the phosphoproteome from a human cell line.
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Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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34
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Toby TK, Fornelli L, Kelleher NL. Progress in Top-Down Proteomics and the Analysis of Proteoforms. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2016; 9:499-519. [PMID: 27306313 PMCID: PMC5373801 DOI: 10.1146/annurev-anchem-071015-041550] [Citation(s) in RCA: 389] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
From a molecular perspective, enactors of function in biology are intact proteins that can be variably modified at the genetic, transcriptional, or post-translational level. Over the past 30 years, mass spectrometry (MS) has become a powerful method for the analysis of proteomes. Prevailing bottom-up proteomics operates at the level of the peptide, leading to issues with protein inference, connectivity, and incomplete sequence/modification information. Top-down proteomics (TDP), alternatively, applies MS at the proteoform level to analyze intact proteins with diverse sources of intramolecular complexity preserved during analysis. Fortunately, advances in prefractionation workflows, MS instrumentation, and dissociation methods for whole-protein ions have helped TDP emerge as an accessible and potentially disruptive modality with increasingly translational value. In this review, we discuss technical and conceptual advances in TDP, along with the growing power of proteoform-resolved measurements in clinical and translational research.
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Affiliation(s)
- Timothy K Toby
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208;
| | - Luca Fornelli
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208
| | - Neil L Kelleher
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208;
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208
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35
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Riley NM, Mullen C, Weisbrod CR, Sharma S, Senko MW, Zabrouskov V, Westphall MS, Syka JEP, Coon JJ. Enhanced Dissociation of Intact Proteins with High Capacity Electron Transfer Dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:520-31. [PMID: 26589699 PMCID: PMC4758868 DOI: 10.1007/s13361-015-1306-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 10/29/2015] [Accepted: 11/05/2015] [Indexed: 05/11/2023]
Abstract
Electron transfer dissociation (ETD) is a valuable tool for protein sequence analysis, especially for the fragmentation of intact proteins. However, low product ion signal-to-noise often requires some degree of signal averaging to achieve high quality MS/MS spectra of intact proteins. Here we describe a new implementation of ETD on the newest generation of quadrupole-Orbitrap-linear ion trap Tribrid, the Orbitrap Fusion Lumos, for improved product ion signal-to-noise via ETD reactions on larger precursor populations. In this new high precursor capacity ETD implementation, precursor cations are accumulated in the center section of the high pressure cell in the dual pressure linear ion trap prior to charge-sign independent trapping, rather than precursor ion sequestration in only the back section as is done for standard ETD. This new scheme increases the charge capacity of the precursor accumulation event, enabling storage of approximately 3-fold more precursor charges. High capacity ETD boosts the number of matching fragments identified in a single MS/MS event, reducing the need for spectral averaging. These improvements in intra-scan dynamic range via reaction of larger precursor populations, which have been previously demonstrated through custom modified hardware, are now available on a commercial platform, offering considerable benefits for intact protein analysis and top down proteomics. In this work, we characterize the advantages of high precursor capacity ETD through studies with myoglobin and carbonic anhydrase.
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Affiliation(s)
- Nicholas M Riley
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | | | | | - Seema Sharma
- Thermo Fisher Scientific, San Jose, CA, 95134, USA
| | | | | | - Michael S Westphall
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | | | - Joshua J Coon
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI, 53706, USA.
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36
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Zhao Y, Sun L, Knierman MD, Dovichi NJ. Fast separation and analysis of reduced monoclonal antibodies with capillary zone electrophoresis coupled to mass spectrometry. Talanta 2016; 148:529-33. [DOI: 10.1016/j.talanta.2015.11.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Revised: 11/04/2015] [Accepted: 11/05/2015] [Indexed: 12/18/2022]
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37
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Affiliation(s)
- Jennifer S Brodbelt
- Department of Chemistry, University of Texas at Austin , Austin, Texas 78712, United States
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38
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Characterization of cetuximab Fc/2 dimers by off-line CZE-MS. Anal Chim Acta 2016; 908:168-76. [PMID: 26826699 DOI: 10.1016/j.aca.2015.12.033] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 12/12/2015] [Accepted: 12/17/2015] [Indexed: 11/30/2022]
Abstract
Monoclonal antibody (mAb) therapeutics attract the largest concern due to their strong therapeutic potency and specificity. The Fc region of mAbs is common to many new biotherapeutics as biosimilar, antibody drug conjugate or fusion protein. Fc region has consequences for Fc-mediated effector functions that might be desirable for therapeutic applications. As a consequence, there is a continuous need for improvement of analytical methods to enable fast and accurate characterization of biotherapeutics. Capillary zone electrophoresis-Mass spectrometry couplings (CZE-MS) appear really attractive methods for the characterization of biological samples. In this report, we used CZE-MS systems developed in house and native MS infusion to allow precise middle-up characterization of Fc/2 variant of cetuximab. Molecular weights were measured for three Fc/2 charge variants detected in the CZE separation of cetuximab subunits. Two Fc/2 C-terminal lysine variants were identified and separated. As the aim is to understand the presence of three peaks in the CZE separation for two Fc/2 subunits, we developed a strategy using CZE-UV/MALDI-MS and CZE-UV/ESI-MS to evaluate the role of N-glycosylation and C-terminal lysine truncation on the CZE separation. The chemical structure of N-glycosylation expressed on the Fc region of cetuximab does not influence CZE separation while C-terminal lysine is significantly influencing separation. In addition, native MS infusion demonstrated the characterization of Fc/2 dimers at pH 5.7 and 6.8 and the first separation of these dimers using CZE-MS.
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39
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Kašička V. Recent developments in capillary and microchip electroseparations of peptides (2013-middle 2015). Electrophoresis 2015; 37:162-88. [DOI: 10.1002/elps.201500329] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 08/25/2015] [Accepted: 08/25/2015] [Indexed: 12/16/2022]
Affiliation(s)
- Václav Kašička
- Institute of Organic Chemistry and Biochemistry, v.v.i; The Czech Academy of Sciences; Prague Czech Republic
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40
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41
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Zhou L, Li Q, Wang J, Huang C, Nice EC. Oncoproteomics: Trials and tribulations. Proteomics Clin Appl 2015; 10:516-31. [PMID: 26518147 DOI: 10.1002/prca.201500081] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/19/2015] [Accepted: 10/27/2015] [Indexed: 02/05/2023]
Affiliation(s)
- Li Zhou
- State Key Laboratory of Biotherapy and Cancer Center; West China Hospital; Sichuan University, and Collaborative Innovation Center for Biotherapy; Chengdu P. R. China
- Department of Neurology; The Affiliated Hospital of Hainan Medical College; Haikou Hainan P. R. China
| | - Qifu Li
- Department of Neurology; The Affiliated Hospital of Hainan Medical College; Haikou Hainan P. R. China
| | - Jiandong Wang
- Department of Biomedical; Chengdu Medical College; Chengdu Sichuan Province P. R. China
| | - Canhua Huang
- State Key Laboratory of Biotherapy and Cancer Center; West China Hospital; Sichuan University, and Collaborative Innovation Center for Biotherapy; Chengdu P. R. China
| | - Edouard C. Nice
- State Key Laboratory of Biotherapy and Cancer Center; West China Hospital; Sichuan University, and Collaborative Innovation Center for Biotherapy; Chengdu P. R. China
- Department of Biochemistry and Molecular Biology; Monash University; Clayton Australia
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42
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Štěpánová S, Kašička V. Recent developments and applications of capillary and microchip electrophoresis in proteomic and peptidomic analyses. J Sep Sci 2015; 39:198-211. [DOI: 10.1002/jssc.201500973] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Revised: 10/06/2015] [Accepted: 10/06/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Sille Štěpánová
- Institute of Organic Chemistry and Biochemistry; The Czech Academy of Sciences; Prague Czech Republic
| | - Václav Kašička
- Institute of Organic Chemistry and Biochemistry; The Czech Academy of Sciences; Prague Czech Republic
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43
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Wang Y, Han Y, Fan E, Zhang K. Analytical strategies used to identify the readers of histone modifications: A review. Anal Chim Acta 2015; 891:32-42. [PMID: 26388362 DOI: 10.1016/j.aca.2015.06.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 10/23/2022]
Abstract
The so-called "readers" of histone post-translational modifications (HPTMs) refer to proteins or complexes that are recruited to HPTMs thus eventually regulate gene transcription. To identify these "readers", mass spectrometry plays an essential role following various enriching strategies. These enriching methods include the use of modified histone peptides/proteins or chemically synthesized histones/nucleosomes containing desired HPTMs to enrich the readers of HPTMs. Despite the peptide- or protein-based assay is straightforward and easy to perform for most labs, this strategy has limited applications for those weak or combinational interactions among various HPTMs and false-positive results are a potential big problem. While the results derived from synthesized histone proteins/nucleosomes is more reliable as it mimics the real chromatic conditions thus is able to analyze the binders of those cross-talked HPTMs, usually the synthesis is so difficult that their applications are impeded for high throughput analysis. In this review, an overview of these analytical techniques is provided and their advantages and disadvantages are discussed.
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Affiliation(s)
- Ye Wang
- Department of Chemistry, Nankai University, 300071 Tianjin, China
| | - Yanpu Han
- Department of Chemistry, Nankai University, 300071 Tianjin, China
| | - Enguo Fan
- Institut für Biochemie und Molekularbiologie, Universität Freiburg, Stefan-Meier-Straße 17, 79104 Freiburg, Germany; School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Jungong Road No. 516, 200093 Shanghai, China.
| | - Kai Zhang
- Department of Biochemistry and Molecular Biology, Tianjin Key Laboratory of Medical Epigenetics, 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Medical University, 300070 Tianjin, China; Department of Chemistry, Nankai University, 300071 Tianjin, China.
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44
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Riley NM, Westphall MS, Coon JJ. Activated Ion Electron Transfer Dissociation for Improved Fragmentation of Intact Proteins. Anal Chem 2015; 87:7109-16. [PMID: 26067513 PMCID: PMC9488116 DOI: 10.1021/acs.analchem.5b00881] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Here we report the first implementation of activated ion electron transfer dissociation (AI-ETD) for top down protein characterization, showing that AI-ETD definitively extends the m/z range over which ETD can be effective for fragmentation of intact proteins. AI-ETD, which leverages infrared photon bombardment concurrent to the ETD reaction to mitigate nondissociative electron transfer, was performed using a novel multipurpose dissociation cell that can perform both beam-type collisional dissociation and ion-ion reactions on an ion trap-Orbitrap hybrid mass spectrometer. AI-ETD increased the number of c- and z-type product ions for all charge states over ETD alone, boosting product ion yield by nearly 4-fold for low charge density precursors. AI-ETD also outperformed HCD, generating more matching fragments for all proteins at all charge states investigated. In addition to generating more unique fragment ions, AI-ETD provided greater protein sequence coverage compared to both HCD and ETD. In all, the effectiveness of AI-ETD across the entirety of the m/z spectrum demonstrates its efficacy for robust fragmentation of intact proteins.
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Affiliation(s)
- Nicholas M. Riley
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
- Genome Center of Wisconsin, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Michael S. Westphall
- Genome Center of Wisconsin, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Joshua J. Coon
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
- Department of Biomolecular Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
- Genome Center of Wisconsin, University of Wisconsin, Madison, Wisconsin 53706, United States
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45
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Riley NM, Rush MJP, Rose CM, Richards AL, Kwiecien NW, Bailey DJ, Hebert AS, Westphall MS, Coon JJ. The Negative Mode Proteome with Activated Ion Negative Electron Transfer Dissociation (AI-NETD). Mol Cell Proteomics 2015; 14:2644-60. [PMID: 26193884 DOI: 10.1074/mcp.m115.049726] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Indexed: 01/15/2023] Open
Abstract
The field of proteomics almost uniformly relies on peptide cation analysis, leading to an underrepresentation of acidic portions of proteomes, including relevant acidic posttranslational modifications. Despite the many benefits negative mode proteomics can offer, peptide anion analysis remains in its infancy due mainly to challenges with high-pH reversed-phase separations and a lack of robust fragmentation methods suitable for peptide anion characterization. Here, we report the first implementation of activated ion negative electron transfer dissociation (AI-NETD) on the chromatographic timescale, generating 7,601 unique peptide identifications from Saccharomyces cerevisiae in single-shot nLC-MS/MS analyses of tryptic peptides-a greater than 5-fold increase over previous results with NETD alone. These improvements translate to identification of 1,106 proteins, making this work the first negative mode study to identify more than 1,000 proteins in any system. We then compare the performance of AI-NETD for analysis of peptides generated by five proteases (trypsin, LysC, GluC, chymotrypsin, and AspN) for negative mode analyses, identifying as many as 5,356 peptides (1,045 proteins) with LysC and 4,213 peptides (857 proteins) with GluC in yeast-characterizing 1,359 proteins in total. Finally, we present the first deep-sequencing approach for negative mode proteomics, leveraging offline low-pH reversed-phase fractionation prior to online high-pH separations and peptide fragmentation with AI-NETD. With this platform, we identified 3,467 proteins in yeast with trypsin alone and characterized a total of 3,730 proteins using multiple proteases, or nearly 83% of the expressed yeast proteome. This work represents the most extensive negative mode proteomics study to date, establishing AI-NETD as a robust tool for large-scale peptide anion characterization and making the negative mode approach a more viable platform for future proteomic studies.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Joshua J Coon
- From the ‡Department of Chemistry, §Genome Center, and ¶Department of Biomolecular Chemistry University of Wisconsin, Madison, Wisconsin, 53706
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