1
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Graham KA, Grisolia VJ, Borotto NB. Mobility-Assisted Pseudo-MS 3 Sequencing of Protein Ions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024. [PMID: 38920020 DOI: 10.1021/jasms.4c00148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/27/2024]
Abstract
The sequencing of intact proteins within a mass spectrometer has many benefits but is frequently limited by the fact that tandem mass spectrometry (MS/MS) techniques often generate poor sequence coverages when applied to protein ions. To overcome this limitation, exotic MS/MS techniques that rely on lasers and radical chemistry have been developed. These techniques generate high sequence coverages, but they require specialized instrumentation, create products through multiple dissociation mechanisms, and often require long acquisition times. Recently, we demonstrated that protein ions can be dissociated in a trapped ion mobility spectrometry (TIMS) device prior to mobility separation in a commercial timsTOF. All generated product ions were distributed throughout the mobility dimension, and this separation enabled deconvolution of complex tandem mass spectra and could enable facile pseudo-MS3 interrogation of generated product ions with the downstream quadrupole and collision cell. A second activation step improves sequence coverage because the most labile bonds have been depleted during the first dissociation and subsequent dissociation events are more evenly distributed throughout the product ion backbone. In this work, we explore the potential of this mobility-assisted pseudo-MS3 (MAP) method on a commercial timsTOF and timsTOF Pro 2. We demonstrate that while MAP only generates 92% of the sequence coverage of the most effective MS/MS technique, it accomplished this feat in 1.5 min and could be facilely integrated with liquid chromatographic separations.
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Affiliation(s)
- Katherine A Graham
- Department of Chemistry, University of Nevada, 1664 N. Virginia Street, Reno, Nevada 89557, United States
| | - Vincent J Grisolia
- Department of Chemistry, University of Nevada, 1664 N. Virginia Street, Reno, Nevada 89557, United States
| | - Nicholas B Borotto
- Department of Chemistry, University of Nevada, 1664 N. Virginia Street, Reno, Nevada 89557, United States
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2
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Daly LA, Clarke CJ, Po A, Oswald SO, Eyers CE. Considerations for defining +80 Da mass shifts in mass spectrometry-based proteomics: phosphorylation and beyond. Chem Commun (Camb) 2023; 59:11484-11499. [PMID: 37681662 PMCID: PMC10521633 DOI: 10.1039/d3cc02909c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/21/2023] [Indexed: 09/09/2023]
Abstract
Post-translational modifications (PTMs) are ubiquitous and key to regulating protein function. Understanding the dynamics of individual PTMs and their biological roles requires robust characterisation. Mass spectrometry (MS) is the method of choice for the identification and quantification of protein modifications. This article focusses on the MS-based analysis of those covalent modifications that induce a mass shift of +80 Da, notably phosphorylation and sulfation, given the challenges associated with their discrimination and pinpointing the sites of modification on a polypeptide chain. Phosphorylation in particular is highly abundant, dynamic and can occur on numerous residues to invoke specific functions, hence robust characterisation is crucial to understanding biological relevance. Showcasing our work in the context of other developments in the field, we highlight approaches for enrichment and site localisation of phosphorylated (canonical and non-canonical) and sulfated peptides, as well as modification analysis in the context of intact proteins (top down proteomics) to explore combinatorial roles. Finally, we discuss the application of native ion-mobility MS to explore the effect of these PTMs on protein structure and ligand binding.
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Affiliation(s)
- Leonard A Daly
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Christopher J Clarke
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Allen Po
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Sally O Oswald
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Claire E Eyers
- Centre for Proteome Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
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3
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Bashyal A, Hui JO, Flick T, Dykstra AB, Zhang Q, Campuzano IDG, Brodbelt JS. Differentiation of Aspartic and Isoaspartic Acid Using 193 nm Ultraviolet Photodissociation Mass Spectrometry. Anal Chem 2023; 95:11510-11517. [PMID: 37458293 PMCID: PMC10588209 DOI: 10.1021/acs.analchem.3c02025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Spontaneous conversion of aspartic acid (Asp) to isoaspartic acid (isoAsp) is a ubiquitous modification that influences the structure and function of proteins. This modification of Asp impacts the stability of biotherapeutics and has been linked to the development of neurodegenerative diseases. We explored the use of 193 nm ultraviolet photodissociation (UVPD) to distinguish Asp and isoAsp in the protonated and deprotonated peptides. The differences in the relative abundances of several fragment ions uniquely generated by UVPD were used to differentiate isomeric peptide standards containing Asp or isoAsp. These fragment ions result from the cleavage of bonds N-terminal to Asp/isoAsp residues in addition to the side-chain losses from Asp/isoAsp or the losses of COOH, CO2, CO, or H2O from y-ions. Fragmentation of Asp-containing tryptic peptides using UVPD resulted in more enhanced w/w + 1/y - 1/x ions, while isoAsp-containing peptides yielded more enhanced y - 18/y - 45/y - 46 ions. UVPD was also used to identify an isomerized peptide from a tryptic digest of a monoclonal antibody. Moreover, UVPD of a protonated nontryptic peptide resulted in more enhanced y ions N- and C-terminal to isoAsp and differences in b/y ion ratios that were used to identify the isoAsp peptide.
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Affiliation(s)
- Aarti Bashyal
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - John O Hui
- Amgen Research, Molecular Analytics, Amgen Inc., Thousand Oaks, California 91320, United States
| | - Tawnya Flick
- Process Development, Attribute Sciences, Amgen Inc., Thousand Oaks, California 91320, United States
| | - Andrew B Dykstra
- Process Development, Attribute Sciences, Amgen Inc., Thousand Oaks, California 91320, United States
| | - Qingchun Zhang
- Process Development, Attribute Sciences, Amgen Inc., Thousand Oaks, California 91320, United States
| | - Iain D G Campuzano
- Amgen Research, Molecular Analytics, Amgen Inc., Thousand Oaks, California 91320, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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4
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Theisen A, Wootton CA, Haris A, Morgan TE, Lam YPY, Barrow MP, O’Connor PB. Enhancing Biomolecule Analysis and 2DMS Experiments by Implementation of (Activated Ion) 193 nm UVPD on a FT-ICR Mass Spectrometer. Anal Chem 2022; 94:15631-15638. [DOI: 10.1021/acs.analchem.2c02354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Alina Theisen
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | | | - Anisha Haris
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Tomos E. Morgan
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Yuko P. Y. Lam
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Mark P. Barrow
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Peter B. O’Connor
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
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5
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Krutilin A, Epp SW, Alejo GML, Busse F, Gitaric D, Schikora H, Schwoerer H, Tellkamp F. Peptide Mass Spectra from Micrometer-Thick Ice Films Produced with Femtosecond Pulses. Anal Chem 2022; 94:13359-13367. [PMID: 36153751 PMCID: PMC9535622 DOI: 10.1021/acs.analchem.2c01810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 08/31/2022] [Indexed: 11/30/2022]
Abstract
We present a cryogenic mass spectrometry protocol with the capability to detect peptides in the attomole dilution range from ice films. Our approach employs femtosecond laser pulses and implements neither substrate modification nor proton donor agents in the aqueous solution, known to facilitate analyte detection in mass spectrometry. In a systematic study, we investigated the impact of temperature, substrate composition, and irradiation wavelength (513 and 1026 nm) on the bradykinin signal onset. Our findings show that substrate choice and irradiation wavelength have a minor impact on signal intensity once the preparation protocol is optimized. However, if the temperature is increased from -140 to 0 °C, which is accompanied by ice film thinning, a somehow complex picture of analyte desorption and ionization is recognizable, which has not been described in the literature yet. Under cryogenic conditions (-140 °C), obtaining a signal is only possible from isolated sweet spots across the film. If the thin ice film is between -100 and -70 °C of temperature, these sweet spots appear more frequently. Ice sublimation triggered by temperatures above -70 °C leads to an intense and robust signal onset that could be maintained for several hours. In addition to the above findings, we notice that a vibrant fragmentation pattern produced is strikingly similar with both wavelengths. Our findings suggest that while following an optimized protocol, femtosecond mass spectrometry has excellent potential to analyze small organic molecules and peptides with a mass range of up to 2.5 kDa in aqueous solution without any matrix, as employed in matrix-assisted laser desorption/ionization (MALDI) or any substrate surface modification, found in surface-assisted laser desorption/ionization (SALDI).
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Affiliation(s)
- Andrey Krutilin
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Sascha W. Epp
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Glaynel M. L. Alejo
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Frederik Busse
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Djordje Gitaric
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Hendrik Schikora
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Heinrich Schwoerer
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Friedjof Tellkamp
- Max
Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
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6
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Edwards HM, Wu HT, Julian RR, Jackson GP. Differentiation of leucine and isoleucine residues in peptides using charge transfer dissociation mass spectrometry (CTD-MS). RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2022; 36:e9246. [PMID: 34927767 DOI: 10.1002/rcm.9246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
RATIONALE The function of a protein or the binding affinity of an antibody can be substantially altered by the replacement of leucine (Leu) with isoleucine (Ile), and vice versa, so the ability to identify the correct isomer using mass spectrometry can help resolve important biological questions. Tandem mass spectrometry approaches for Leu/Ile (Xle) discrimination have been developed, but they all have certain limitations. METHODS Four model peptides and two wild-type peptide sequences containing either Leu or Ile residues were subjected to charge transfer dissociation (CTD) mass spectrometry on a modified three-dimensional ion trap. The peptides were analyzed in both the 1+ and 2+ charge states, and the results were compared to conventional collision-induced dissociation spectra of the same peptides obtained using the same instrument. RESULTS CTD resulted in 100% sequence coverage for each of the studied peptides and provided a variety of side-chain cleavages, including d, w and v ions. Using CTD, reliable d and w ions of Xle residues were observed more than 80% of the time. When present, d ions are typically greater than 10% of the abundance of the corresponding a ions from which they derive, and w ions are typically more abundant than the z ions from which they derive. CONCLUSIONS CTD has the benefit of being applicable to both 1+ and 2+ precursor ions, and the overall performance is comparable to that of other high-energy activation techniques like hot electron capture dissociation and UV photodissociation. CTD does not require chemical modifications of the precursor peptides, nor does it require additional levels of isolation and fragmentation.
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Affiliation(s)
- Halle M Edwards
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
| | - Hoi-Ting Wu
- Department of Chemistry, University of California, Riverside, CA, USA
| | - Ryan R Julian
- Department of Chemistry, University of California, Riverside, CA, USA
| | - Glen P Jackson
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, WV, USA
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7
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Edwards HM, Wu HT, Julian RR, Jackson GP. Differentiating aspartic acid isomers and epimers with charge transfer dissociation mass spectrometry (CTD-MS). Analyst 2022; 147:1159-1168. [PMID: 35188507 DOI: 10.1039/d1an02279b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ability to understand the function of a protein often relies on knowledge about its detailed structure. Sometimes, seemingly insignificant changes in the primary structure of a protein, like an amino acid substitution, can completely disrupt a protein's function. Long-lived proteins (LLPs), which can be found in critical areas of the human body, like the brain and eye, are especially susceptible to primary sequence alterations in the form of isomerization and epimerization. Because long-lived proteins do not have the corrective regeneration capabilities of most other proteins, points of isomerism and epimerization that accumulate within the proteins can severely hamper their functions and can lead to serious diseases like Alzheimer's disease, cancer and cataracts. Whereas tandem mass spectrometry (MS/MS) in the form of collision-induced dissociation (CID) generally excels at peptide characterization, MS/MS often struggles to pinpoint modifications within LLPs, especially when the differences are only isomeric or epimeric in nature. One of the most prevalent and difficult-to-identify modifications is that of aspartic acid between its four isomeric forms: L-Asp, L-isoAsp, D-Asp, and D-isoAsp. In this study, peptides containing isomers of Asp were analyzed by charge transfer dissociation (CTD) mass spectrometry to identify spectral features that could discriminate between the different isomers. For the four isomers of Asp in three model peptides, CTD produced diagnostic ions of the form cn+57 on the N-terminal side of iso-Asp residues, but not on the N-terminal side of Asp residues. Using CTD, the L- and D forms of Asp and isoAsp could also be differentiated based on the relative abundance of y- and z ions on the C-terminal side of Asp residues. Differentiation was accomplished through a chiral discrimination factor, R, which compares an ion ratio in a spectrum of one epimer or isomer to the same ion ratio in the spectrum of a different epimer or isomer. The R values obtained using CTD are as robust and statistically significant as other fragmentation techniques, like radical directed dissociation (RDD). In summary, the extent of backbone and side-chain fragments produced by CTD enabled the differentiation of isomers and epimers of Asp in a variety of peptides.
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Affiliation(s)
- Halle M Edwards
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA.
| | - Hoi-Ting Wu
- Department of Chemistry, University of California, Riverside, CA, USA
| | - Ryan R Julian
- Department of Chemistry, University of California, Riverside, CA, USA
| | - Glen P Jackson
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA. .,Department of Forensic and Investigative Science, West Virginia University, Morgantown, WV, USA
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8
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Macias LA, Sipe SN, Santos IC, Bashyal A, Mehaffey MR, Brodbelt JS. Influence of Primary Structure on Fragmentation of Native-Like Proteins by Ultraviolet Photodissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:2860-2873. [PMID: 34714071 PMCID: PMC8639798 DOI: 10.1021/jasms.1c00269] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Analysis of native-like protein structures in the gas phase via native mass spectrometry and auxiliary techniques has become a powerful tool for structural biology applications. In combination with ultraviolet photodissociation (UVPD), native top-down mass spectrometry informs backbone flexibility, topology, hydrogen bonding networks, and conformational changes in protein structure. Although it is known that the primary structure affects dissociation of peptides and proteins in the gas phase, its effect on the types and locations of backbone cleavages promoted by UVPD and concomitant influence on structural characterization of native-like proteins is not well understood. Here, trends in the fragmentation of native-like proteins were evaluated by tracking the propensity of 10 fragment types (a, a+1, b, c, x, x+1, y, y-1, Y, and z) in relation to primary structure in a native-top down UVPD data set encompassing >9600 fragment ions. Differing fragmentation trends are reported for the production of distinct fragment types, attributed to a combination of both direct dissociation pathways from excited electronic states and those surmised to involve intramolecular vibrational energy redistribution after internal conversion. The latter pathways were systematically evaluated to evince the role of proton mobility in the generation of "CID-like" fragments through UVPD, providing pertinent insight into the characterization of native-like proteins. Fragmentation trends presented here are envisioned to enhance analysis of the protein higher-order structure or augment scoring algorithms in the high-throughput analysis of intact proteins.
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Affiliation(s)
- Luis A Macias
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Sarah N Sipe
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Inês C Santos
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Aarti Bashyal
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - M Rachel Mehaffey
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
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9
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Pepi LE, Leach FE, Klein DR, Brodbelt JS, Amster IJ. Investigation of the Experimental Parameters of Ultraviolet Photodissociation for the Structural Characterization of Chondroitin Sulfate Glycosaminoglycan Isomers. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1759-1770. [PMID: 34096288 PMCID: PMC8377745 DOI: 10.1021/jasms.1c00119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Glycosaminoglycans (GAGs) are linear polysaccharides that participate in a broad range of biological functions. Their incomplete biosynthesis pathway leads to nonuniform chains and complex mixtures. For this reason, the characterization of GAGs has been a difficult hurdle for the analytical community. Recently, ultraviolet photodissociation (UVPD) has emerged as a useful tool for determining sites of modification within a GAG chain. Here, we investigate the ability for UVPD to distinguish chondroitin sulfate epimers and the effects of UVPD experimental parameters on fragmentation efficiency. Chondroitin sulfate A (CS-A) and chondroitin sulfate B (CS-B), commonly referred to as dermatan sulfate (DS), differ only in C-5 uronic acid stereochemistry. This uronic acid difference can influence GAG-protein binding and therefore can alter the specific biological function of a GAG chain. Prior tandem mass spectrometry methods investigated for the elucidation of GAG structures also have difficulty differentiating 4-O from 6-O sulfation in chondroitin sulfate GAGs. Preliminary data using UVPD to characterize GAGs showed a promising ability to characterize 4-O sulfation in CS-A GAGs. Here, we look in depth at the capability of UVPD to distinguish chondroitin sulfate C-5 diastereomers and the role of key experimental parameters in making this distinction. Results using a 193 nm excimer laser and a 213 nm solid-state laser are compared for this study. The effect of precursor ionization state, the number of laser pulses (193 or 213 nm UVPD), and the use of the low-pressure versus high-pressure trap are investigated.
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Affiliation(s)
- Lauren E Pepi
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Franklin E Leach
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
- Department of Environmental Health Sciences, University of Georgia, Athens, Georgia 30602, United States
| | - Dustin R Klein
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - I Jonathan Amster
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
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10
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Becher S, Wang H, Leeming MG, Donald WA, Heiles S. Influence of protein ion charge state on 213 nm top-down UVPD. Analyst 2021; 146:3977-3987. [PMID: 34009215 DOI: 10.1039/d1an00571e] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultraviolet photodissociation (UVPD) is a powerful and rapidly developing method in top-down proteomics. Sequence coverages can exceed those obtained with collision- and electron-induced fragmentation methods. Because of the recent interest in UVPD, factors that influence protein fragmentation and sequence coverage are actively debated in the literature. Here, we performed top-down 213 nm UVPD experiments on a 7 T Fourier-transform ion cyclotron resonance mass spectrometer (FT-ICR MS) for the model proteins ubiquitin, myoglobin and cytochrome c that were electrosprayed from native, denaturing and supercharging solutions in order to investigate the effect of protein charge states on UVPD fragments. By performing UVPD in ultrahigh vacuum, factors associated with collisional cooling and any ion activation during transfer between mass analyzers can be largely eliminated. Sequence coverage increased from <10% for low charge states to >60% for high charge states for all three proteins. This trend is influenced by the overall charge state, i.e., charges per number of amino acid residues, and to a lesser degree by associated structural changes of protein ions of different charge states based on comparisons to published collision-cross section measurements. To rationalize this finding, and correlate sequence ion formation and identity with the number and location of protons, UVPD results were compared to protonation sites predicted based on electrostatic modelling. Assuming confined protonation sites, these results indicate the presence of two general fragmentation types; i.e., charge remote and charge directed. For moderately high protein charge states, fragment ions mostly originate in regions between likely protonation sites (charge remote), whereas sequence ions of highly charge protein ions occur either near backbone amide protonation sites at low-basicity residues (charge directed) or at charge remote sites (i.e., high-basicity residues). Overall, our results suggest that top-down 213 UVPD performance in the zero-pressure limit depends strongly on protein charge states and protonation sites can influence the location of backbone cleavages.
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Affiliation(s)
- Simon Becher
- Institute of Inorganic and Analytical Chemistry, Justus Liebig University Giessen, 35392 Giessen, Germany.
| | - Huixin Wang
- Mark Wainwright Analytical Centre, University of New South Wales, New South Wales, Australia
| | - Michael G Leeming
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria, Australia
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia
| | - Sven Heiles
- Institute of Inorganic and Analytical Chemistry, Justus Liebig University Giessen, 35392 Giessen, Germany.
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11
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Asakawa D, Takahashi H, Iwamoto S, Tanaka K. Gas-Phase Peptide Fragmentation Induced by Hydrogen Attachment, from Principle to Sequencing of Amide Nitrogen-Methylated Peptides. Anal Chem 2020; 92:15773-15780. [PMID: 33256396 DOI: 10.1021/acs.analchem.0c02766] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tandem mass spectrometry (MS/MS) with radical-based fragmentation was developed recently, which involves the reaction of hydrogen atoms and peptides in a process called hydrogen attachment/abstraction dissociation (HAD). HAD mainly produces [cn + 2H]+ and [zm + 2H]+ via hydrogen attachment to the carbonyl oxygen on the peptide backbone. In addition, HAD often generates [an + 2H]+ and [xm + 2H]+. To explain the formation of [an + 2H]+ and [xm + 2H]+, hydrogen attachment to the carbonyl carbon atom on the peptide backbone is proposed to initiate Cα-C bond cleavage. The resultant hydrogen-abundant oxygen-centered radical intermediate undergoes radical-induced dissociation to give [an + H]+• and [xm + 2H]+. Subsequently, [an + 2H]+ was produced by the reaction of [an + H]+• and a hydrogen atom. The fragment ions formed by the cleavage of N-Cα and Cα-C bonds are observed in the HAD-MS/MS spectra, and the mass differences of these fragment ions correspond to the mass of peptide bonds. Consequently, HAD-MS/MS allows the identification of post-translational modifications on the peptide backbone. In addition, HAD-MS/MS provides a consecutive series of [cn + 2H]+ and [an + 2H]+ as the N-terminal fragments, as well as [zm + 2H]+ and [xm + 2H]+, which enables the sequencing of peptides with post-translational modification, including the discrimination of modifications on the side chain and backbone.
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Affiliation(s)
- Daiki Asakawa
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - Hidenori Takahashi
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo-Kuwabaracho, Nakagyo-ku, Kyoto 604-8511, Japan
| | - Shinichi Iwamoto
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo-Kuwabaracho, Nakagyo-ku, Kyoto 604-8511, Japan
| | - Koichi Tanaka
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo-Kuwabaracho, Nakagyo-ku, Kyoto 604-8511, Japan
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12
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Crittenden CM, Novelli ET, Mehaffey MR, Xu GN, Giles DH, Fies WA, Dalby KN, Webb LJ, Brodbelt JS. Structural Evaluation of Protein/Metal Complexes via Native Electrospray Ultraviolet Photodissociation Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:1140-1150. [PMID: 32275426 PMCID: PMC7386362 DOI: 10.1021/jasms.0c00066] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Ultraviolet photodissociation (UVPD) has emerged as a promising tool to characterize proteins with regard to not only their primary sequences and post-translational modifications, but also their tertiary structures. In this study, three metal-binding proteins, Staphylococcal nuclease, azurin, and calmodulin, are used to demonstrate the use of UVPD to elucidate metal-binding regions via comparisons between the fragmentation patterns of apo (metal-free) and holo (metal-bound) proteins. The binding of staphylococcal nuclease to calcium was evaluated, in addition to a series of lanthanide(III) ions which are expected to bind in a similar manner as calcium. On the basis of comparative analysis of the UVPD spectra, the binding region for calcium and the lanthanide ions was determined to extend from residues 40-50, aligning with the known crystal structure. Similar analysis was performed for both azurin (interrogating copper and silver binding) and calmodulin (four calcium binding sites). This work demonstrates the utility of UVPD methods for determining and analyzing the metal binding sites of a variety of classes of proteins.
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Affiliation(s)
| | - Elisa T Novelli
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - M Rachel Mehaffey
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - Gulan N Xu
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - David H Giles
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, Texas 78712, United States
| | - Whitney A Fies
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - Kevin N Dalby
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, Texas 78712, United States
- Graduate Program in Cell and Molecular Biology, University of Texas, Austin, Texas 78712, United States
| | - Lauren J Webb
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
- Institute for Cell and Molecular Biology, University of Texas, Austin, Texas 78712, United States
- Texas Materials Institute, University of Texas, Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
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13
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Brodbelt JS, Morrison LJ, Santos I. Ultraviolet Photodissociation Mass Spectrometry for Analysis of Biological Molecules. Chem Rev 2020; 120:3328-3380. [PMID: 31851501 PMCID: PMC7145764 DOI: 10.1021/acs.chemrev.9b00440] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The development of new ion-activation/dissociation methods continues to be one of the most active areas of mass spectrometry owing to the broad applications of tandem mass spectrometry in the identification and structural characterization of molecules. This Review will showcase the impact of ultraviolet photodissociation (UVPD) as a frontier strategy for generating informative fragmentation patterns of ions, especially for biological molecules whose complicated structures, subtle modifications, and large sizes often impede molecular characterization. UVPD energizes ions via absorption of high-energy photons, which allows access to new dissociation pathways relative to more conventional ion-activation methods. Applications of UVPD for the analysis of peptides, proteins, lipids, and other classes of biologically relevant molecules are emphasized in this Review.
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Affiliation(s)
- Jennifer S. Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Lindsay J. Morrison
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Inês Santos
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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14
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Miyazawa K, Takayama M. Multiple Hydrogen Loss from [M + H] + and [a] + ions of Peptides in MALDI In-Source Decay Using a Dinitro-Substituted Matrix. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:547-552. [PMID: 32126775 DOI: 10.1021/jasms.9b00013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The formation and radical-directed dissociation of multiple hydrogen-abstracted peptide cations [M + H - mH]·+ has been reported using MALDI-ISD with dinitro-substituted matrices. The MALDI-ISD of synthetic peptides using 3,5-dinitrosalicylic acid (3,5-DNSA) and 3,4-dinitrobenzoic acid (3,4-DNBA) as matrices resulted in multiple hydrogen abstraction from the analyte [M + H]+ and fragment [a]+ ions, i.e., [M + H - mH]+ and [a - mH]+ (m = 1-8). All of the ISD spectra showed unusually intense [a]+ ions originating from cleavage at the Cα-C bond of the Leu-Xxx residues when peptides without Phe/Tyr/His/Cys residues were used. The intensity of the [an]+ series ions generated using 3,5-DNSA and 3,4-DNBA rapidly decreased with increasing residue number n, suggesting cleavage at multiradical sites of [M + H - mH]•+. It was suggested that multiple hydrogen abstraction from protonated peptides [M + H]+ mainly takes place from the backbone amide nitrogen.
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Affiliation(s)
- Kei Miyazawa
- Mass Spectrometry Laboratory, Graduate School in Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
| | - Mitsuo Takayama
- Mass Spectrometry Laboratory, Graduate School in Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
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15
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Pereverzev AY, Koczor-Benda Z, Saparbaev E, Kopysov VN, Rosta E, Boyarkin OV. Spectroscopic Evidence for Peptide-Bond-Selective Ultraviolet Photodissociation. J Phys Chem Lett 2020; 11:206-209. [PMID: 31846339 DOI: 10.1021/acs.jpclett.9b03221] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We study the photodissociation induced by ultraviolet excitation of amide bonds in gas-phase protonated peptides. Jointly, mass spectrometry and cold ion spectroscopy provide evidence for a selective nonstatistical dissociation of specific peptide bonds in the spectral region of the formally forbidden n → π* transition of amide groups. Structural analysis reveals that the activation of this transition, peaked at 226 nm, originates from the nonplanar geometry of the bond. In contrast, the statistical dissociation in the electronic ground state appears to be the main outcome of the π → π* excitation of the peptide bonds at 193 nm. We propose a tentative model that explains the difference in the fragmentation mechanisms by the difference in localization of the electronic transitions and the higher amount of vibrational energy released in the electronic excited state upon absorption at 193 nm.
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Affiliation(s)
- Aleksandr Y Pereverzev
- Laboratoire de Chimie Physique Moléculaire , École Polytechnique Fédérale de Lausanne , Station-6 , 1015 Lausanne , Switzerland
| | - Zsuzsanna Koczor-Benda
- Department of Chemistry , King's College London , Britannia House, 7 Trinity Street , London SE1 1DB , United Kingdom
| | - Erik Saparbaev
- Laboratoire de Chimie Physique Moléculaire , École Polytechnique Fédérale de Lausanne , Station-6 , 1015 Lausanne , Switzerland
| | - Vladimir N Kopysov
- Laboratoire de Chimie Physique Moléculaire , École Polytechnique Fédérale de Lausanne , Station-6 , 1015 Lausanne , Switzerland
| | - Edina Rosta
- Department of Chemistry , King's College London , Britannia House, 7 Trinity Street , London SE1 1DB , United Kingdom
| | - Oleg V Boyarkin
- Laboratoire de Chimie Physique Moléculaire , École Polytechnique Fédérale de Lausanne , Station-6 , 1015 Lausanne , Switzerland
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16
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Milosavljević AR, Jänkälä K, Ranković ML, Canon F, Bozek J, Nicolas C, Giuliani A. Oxygen K-shell spectroscopy of isolated progressively solvated peptide. Phys Chem Chem Phys 2020; 22:12909-12917. [DOI: 10.1039/d0cp00994f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
X-ray spectroscopy of an isolated controllably hydrated peptide: core excitation of the first solvation shell enhances peptide backbone fragmentation.
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Affiliation(s)
| | - Kari Jänkälä
- Nano and Molecular Systems Research Unit
- University of Oulu
- 90014 Oulu
- Finland
| | | | - Francis Canon
- Centre des Sciences du Goût et de l’Alimentation
- CNRS
- INRAE
- Université de Bourgogne Franche-Comté
- France
| | - John Bozek
- SOLEIL, l’Orme des Merisiers
- 91192 Gif sur Yvette Cedex
- France
| | | | - Alexandre Giuliani
- SOLEIL, l’Orme des Merisiers
- 91192 Gif sur Yvette Cedex
- France
- INRAE
- UAR1008
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17
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Klein DR, Leach FE, Amster IJ, Brodbelt JS. Structural Characterization of Glycosaminoglycan Carbohydrates Using Ultraviolet Photodissociation. Anal Chem 2019; 91:6019-6026. [PMID: 30932467 DOI: 10.1021/acs.analchem.9b00521] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Structural characterization of sulfated glycosaminoglycans (GAGs) by mass spectrometry has long been a formidable analytical challenge owing to their high structural variability and the propensity for sulfate decomposition upon activation with low-energy ion activation methods. While derivatization and complexation workflows have aimed to generate informative spectra using low-energy ion activation methods, alternative ion activation methods present the opportunity to obtain informative spectra from native GAG structures. Both electron- and photon-based activation methods, including electron detachment dissociation (EDD), negative electron transfer dissociation (NETD), and extreme ultraviolet photon activation, have been explored previously to overcome the limitations associated with low-energy activation methods for GAGs and other sulfated oligosaccharides. Further, implementation of such methods on high-resolution mass spectrometers has aided the interpretation of the complex spectra generated. Here, we explore ultraviolet photodissociation (UVPD) implemented on an Orbitrap mass spectrometer as another option for structural characterization of GAGs. UVPD spectra for both dermatan and heparan sulfate structures display extensive fragmentation including both glycosidic and cross-ring cleavages with the extent of sulfate retention comparable to that observed by EDD and NETD. In addition, the relatively short activation time of UVPD makes it promising for higher throughput analysis of GAGs in complex mixtures.
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Affiliation(s)
- Dustin R Klein
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
| | - Franklin E Leach
- Department of Environmental Health Science , The University of Georgia , Athens , Georgia 30602 , United States
| | - I Jonathan Amster
- Department of Chemistry , The University of Georgia , Athens , Georgia 30602 , United States
| | - Jennifer S Brodbelt
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
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18
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Stiving AQ, VanAernum ZL, Busch F, Harvey SR, Sarni SH, Wysocki VH. Surface-Induced Dissociation: An Effective Method for Characterization of Protein Quaternary Structure. Anal Chem 2019; 91:190-209. [PMID: 30412666 PMCID: PMC6571034 DOI: 10.1021/acs.analchem.8b05071] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Alyssa Q. Stiving
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
| | - Zachary L. VanAernum
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
| | - Florian Busch
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Campus Chemical Instrument Center, The Ohio State University, Columbus, OH 43210
| | - Sophie R. Harvey
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Campus Chemical Instrument Center, The Ohio State University, Columbus, OH 43210
| | - Samantha H. Sarni
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210
- The Center for RNA Biology, The Ohio State University, Columbus, OH 43210
| | - Vicki H. Wysocki
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
- Campus Chemical Instrument Center, The Ohio State University, Columbus, OH 43210
- The Center for RNA Biology, The Ohio State University, Columbus, OH 43210
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19
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Neidel C, Kuehn A, Schulz CP, Hertel IV, Linscheid MW, Schultz T. Femtosecond laser-induced dissociation (fs-LID) as an activation method in mass spectrometry. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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Nagoshi K, Yamakoshi M, Sakamoto K, Takayama M. Specific Cα-C Bond Cleavage of β-Carbon-Centered Radical Peptides Produced by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:1473-1483. [PMID: 29675742 DOI: 10.1007/s13361-018-1958-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 03/14/2018] [Accepted: 03/29/2018] [Indexed: 06/08/2023]
Abstract
Radical-driven dissociation (RDD) of hydrogen-deficient peptide ions [M - H + H]·+ has been examined using matrix-assisted laser dissociation/ionization in-source decay mass spectrometry (MALDI-ISD MS) with the hydrogen-abstracting matrices 4-nitro-1-naphthol (4,1-NNL) and 5-nitrosalicylic acid (5-NSA). The preferential fragment ions observed in the ISD spectra include N-terminal [a] + ions and C-terminal [x]+, [y + 2]+, and [w]+ ions which imply that β-carbon (Cβ)-centered radical peptide ions [M - Hβ + H]·+ are predominantly produced in MALDI conditions. RDD reactions from the peptide ions [M - Hβ + H]·+ successfully explains the fact that both [a]+ and [x]+ ions arising from cleavage at the Cα-C bond of the backbone of Gly-Xxx residues are missing from the ISD spectra. Furthermore, the formation of [a]+ ions originating from the cleavage of Cα-C bond of deuterated Ala(d3)-Xxx residues indicates that the [a]+ ions are produced from the peptide ions [M - Hβ + H]·+ generated by deuteron-abstraction from Ala(d3) residues. It is suggested that from the standpoint of hydrogen abstraction via direct interactions between the nitro group of matrix and hydrogen of peptides, the generation of the peptide radical ions [M - Hβ + H]·+ is more favorable than that of the α-carbon (Cα)-centered radical ions [M - Hα + H]·+ and the amide nitrogen-centered radical ions [M - HN + H]·+, while ab initio calculations indicate that the formation of [M - Hα + H]·+ is energetically most favorable. Graphical Abstract ᅟ.
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Affiliation(s)
- Keishiro Nagoshi
- Mass Spectrometry Laboratory, Graduate School in Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
| | - Mariko Yamakoshi
- Mass Spectrometry Laboratory, Graduate School in Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
| | - Kenya Sakamoto
- Mass Spectrometry Laboratory, Graduate School in Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
| | - Mitsuo Takayama
- Mass Spectrometry Laboratory, Graduate School in Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan.
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21
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Brodie NI, Huguet R, Zhang T, Viner R, Zabrouskov V, Pan J, Petrotchenko EV, Borchers CH. Top-Down Hydrogen-Deuterium Exchange Analysis of Protein Structures Using Ultraviolet Photodissociation. Anal Chem 2018; 90:3079-3082. [PMID: 29336549 DOI: 10.1021/acs.analchem.7b03655] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Top-down hydrogen-deuterium exchange (HDX) analysis using electron capture or transfer dissociation Fourier transform mass spectrometry (FTMS) is a powerful method for the analysis of secondary structure of proteins in solution. The resolution of the method is a function of the degree of fragmentation of backbone bonds in the proteins. While fragmentation is usually extensive near the N- and C-termini, electron capture (ECD) or electron transfer dissociation (ETD) fragmentation methods sometimes lack good coverage of certain regions of the protein, most often in the middle of the sequence. Ultraviolet photodissociation (UVPD) is a recently developed fast-fragmentation technique, which provides extensive backbone fragmentation that can be complementary in sequence coverage to the aforementioned electron-based fragmentation techniques. Here, we explore the application of electrospray ionization (ESI)-UVPD FTMS on an Orbitrap Fusion Lumos Tribrid mass spectrometer to top-down HDX analysis of proteins. We have incorporated UVPD-specific fragment-ion types and fragment-ion mixtures into our isotopic envelope fitting software (HDX Match) for the top-down HDX analysis. We have shown that UVPD data is complementary to ETD, thus improving the overall resolution when used as a combined approach.
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Affiliation(s)
- Nicholas I Brodie
- University of Victoria -Genome British Columbia Proteomics Centre , No. 3101-4464 Markham Street, Vancouver Island Technology Park , Victoria , British Columbia V8Z 7X8 , Canada
| | - Romain Huguet
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Terry Zhang
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Rosa Viner
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Vlad Zabrouskov
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Jingxi Pan
- University of Victoria -Genome British Columbia Proteomics Centre , No. 3101-4464 Markham Street, Vancouver Island Technology Park , Victoria , British Columbia V8Z 7X8 , Canada
| | - Evgeniy V Petrotchenko
- University of Victoria -Genome British Columbia Proteomics Centre , No. 3101-4464 Markham Street, Vancouver Island Technology Park , Victoria , British Columbia V8Z 7X8 , Canada
| | - Christoph H Borchers
- University of Victoria -Genome British Columbia Proteomics Centre , No. 3101-4464 Markham Street, Vancouver Island Technology Park , Victoria , British Columbia V8Z 7X8 , Canada.,Department of Biochemistry and Microbiology , University of Victoria , Petch Building, Room 270d, 3800 Finnerty Road , Victoria , British Columbia V8P 5C2 , Canada.,Gerald Bronfman Department of Oncology, Jewish General Hospital , McGill University , 3755 Côte Ste-Catherine Road , Montreal , Quebec H3T 1E2 , Canada.,Proteomics Centre, Segal Cancer Centre, Lady Davis Institute, Jewish General Hospital , McGill University , 3755 Côte Ste-Catherine Road , Montreal , Quebec H3T 1E2 , Canada
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22
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Mistarz UH, Bellina B, Jensen PF, Brown JM, Barran PE, Rand KD. UV Photodissociation Mass Spectrometry Accurately Localize Sites of Backbone Deuteration in Peptides. Anal Chem 2017; 90:1077-1080. [DOI: 10.1021/acs.analchem.7b04683] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Ulrik H. Mistarz
- Department
of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Bruno Bellina
- Michael
Barber Centre for Collaborative Mass Spectrometry, Manchester Institute
of Biotechnology, and Photon Science Institute, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Pernille F. Jensen
- Department
of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Jeffery M. Brown
- Waters Corporation, Stamford
Avenue, Altrincham Road, Wilmslow, SK9 4AX, United Kingdom
| | - Perdita E. Barran
- Michael
Barber Centre for Collaborative Mass Spectrometry, Manchester Institute
of Biotechnology, and Photon Science Institute, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Kasper D. Rand
- Department
of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
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23
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Quick MM, Mehaffey MR, Johns RW, Parker WR, Brodbelt JS. SITS Derivatization of Peptides to Enhance 266 nm Ultraviolet Photodissociation (UVPD). JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1462-1472. [PMID: 28315237 DOI: 10.1007/s13361-017-1650-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/01/2017] [Accepted: 03/03/2017] [Indexed: 06/06/2023]
Abstract
N-terminal derivatization of peptides with the chromogenic reagent 4-acetamido-4-isothiocyanatostilbene-2,2-disulfonic acid (SITS) is demonstrated to enhance the efficiency of 266 nm ultraviolet photodissociation (UVPD). Attachment of the chromophore results in a mass shift of 454 Da and provides significant gains in the number and abundances of diagnostic fragment ions upon UVPD. Activation of SITS-tagged peptides with 266 nm UVPD leads to many fragment ions akin to the a/b/y ions commonly produced by CID, along with other sequence ions (c, x, and z) typically accessed through higher energy pathways. Extreme bias towards C-terminal fragment ions is observed upon activation of SITS-tagged peptides using multiple 266 nm laser pulses. Due to the high reaction efficiency of the isothiocyanate coupling to the N-terminus of peptides, we demonstrate the ability to adapt this strategy to a high-throughput LC-MS/MS workflow with 266 nm UVPD. Graphical Abstract ᅟ.
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Affiliation(s)
- M Montana Quick
- Department of Chemistry, University of Texas, Austin, TX, 78712, USA
| | - M Rachel Mehaffey
- Department of Chemistry, University of Texas, Austin, TX, 78712, USA
| | - Robert W Johns
- Department of Chemistry, University of California, Berkeley, CA, 94720, USA
- McKetta Department of Chemical Engineering, University of Texas, Austin, TX, 78712, USA
| | - W Ryan Parker
- Department of Chemistry, University of Texas, Austin, TX, 78712, USA
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24
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DeGraan-Weber N, Zhang J, Reilly JP. Distinguishing Aspartic and Isoaspartic Acids in Peptides by Several Mass Spectrometric Fragmentation Methods. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:2041-2053. [PMID: 27613306 PMCID: PMC5748252 DOI: 10.1007/s13361-016-1487-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/17/2016] [Accepted: 08/19/2016] [Indexed: 05/21/2023]
Abstract
Six ion fragmentation techniques that can distinguish aspartic acid from its isomer, isoaspartic acid, were compared. MALDI post-source decay (PSD), MALDI 157 nm photodissociation, tris(2,4,6-trimethoxyphenyl)phosphonium bromide (TMPP) charge tagging in PSD and photodissociation, ESI collision-induced dissociation (CID), electron transfer dissociation (ETD), and free-radical initiated peptide sequencing (FRIPS) with CID were applied to peptides containing either aspartic or isoaspartic acid. Diagnostic ions, such as the y-46 and b+H2O, are present in PSD, photodissociation, and charge tagging. c•+57 and z-57 ions are observed in ETD and FRIPS experiments. For some molecules, aspartic and isoaspartic acid yield ion fragments with significantly different intensities. ETD and charge tagging appear to be most effective at distinguishing these residues. Graphical Abstract ᅟ.
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Affiliation(s)
- Nick DeGraan-Weber
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Jun Zhang
- Pre-Pivotal Drug Product Technologies, Amgen Inc., Thousand Oaks, CA, 91320, USA
| | - James P Reilly
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN, 47405, USA.
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25
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Schwartz AJ, Shelley JT, Walton CL, Williams KL, Hieftje GM. Atmospheric-pressure ionization and fragmentation of peptides by solution-cathode glow discharge. Chem Sci 2016; 7:6440-6449. [PMID: 28451101 PMCID: PMC5356034 DOI: 10.1039/c6sc02032a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/24/2016] [Indexed: 12/13/2022] Open
Abstract
Modern "-omics" (e.g., proteomics, glycomics, metabolomics, etc.) analyses rely heavily on electrospray ionization and tandem mass spectrometry to determine the structural identity of target species. Unfortunately, these methods are limited to specialized mass spectrometry instrumentation. Here, a novel approach is described that enables ionization and controlled, tunable fragmentation of peptides at atmospheric pressure. In the new source, a direct-current plasma is sustained between a tapered metal rod and a flowing sample-containing solution. As the liquid stream contacts the electrical discharge, peptides from the solution are volatilized, ionized, and fragmented. At high discharge currents (e.g., 70 mA), electrospray-like spectra are observed, dominated by singly and doubly protonated molecular ions. At lower currents (35 mA), many peptides exhibit extensive fragmentation, with a-, b-, c-, x-, and y-type ion series present as well as complex fragments, such as d-type ions, not previously observed with atmospheric-pressure dissociation. Though the mechanism of fragmentation is currently unclear, observations indicate it could result from the interaction of peptides with gas-phase radicals or ultraviolet radiation generated within the plasma.
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Affiliation(s)
- Andrew J Schwartz
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA . ; Tel: +1-330-672-2986
| | - Jacob T Shelley
- Department of Chemistry and Biochemistry , Kent State University , Kent , OH 44242 , USA
| | - Courtney L Walton
- Department of Chemistry and Biochemistry , Kent State University , Kent , OH 44242 , USA
| | - Kelsey L Williams
- Department of Chemistry and Biochemistry , Kent State University , Kent , OH 44242 , USA
| | - Gary M Hieftje
- Department of Chemistry , Indiana University , Bloomington , IN 47405 , USA . ; Tel: +1-330-672-2986
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26
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Halim MA, Girod M, MacAleese L, Lemoine J, Antoine R, Dugourd P. Combined Infrared Multiphoton Dissociation with Ultraviolet Photodissociation for Ubiquitin Characterization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:1435-42. [PMID: 27287047 PMCID: PMC5031736 DOI: 10.1007/s13361-016-1419-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 05/10/2023]
Abstract
Herein we report the successful implementation of the consecutive and simultaneous photodissociation with high (213 nm) and low (10.6 μm) energy photons (HiLoPD, high-low photodissociation) on ubiquitin in a quadrupole-Orbitrap mass spectrometer. Absorption of high-energy UV photon is dispersed over the whole protein and stimulates extensive C-Cα backbone fragmentation, whereas low-energy IR photon gradually increases the internal energy and thus preferentially dissociates the most labile amide (C-N) bonds. We noticed that simultaneous irradiation of UV and IR lasers on intact ubiquitin in a single MS/MS experiment provides a rich and well-balanced fragmentation array of a/x, b/y, and z ions. Moreover, secondary fragmentation from a/x and z ions leads to the formation of satellite side-chain ions (d, v, and w) and can help to distinguish isomeric residues in a protein. Implementation of high-low photodissociation in a high-resolution mass spectrometer may offer considerable benefits to promote a comprehensive portrait of protein characterization. Graphical Abstract ᅟ.
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Affiliation(s)
- Mohammad A Halim
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne, France
| | - Marion Girod
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Université Lyon 1, ENS Lyon, 69100, Villeurbanne, France
| | - Luke MacAleese
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne, France
| | - Jérôme Lemoine
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Université Lyon 1, ENS Lyon, 69100, Villeurbanne, France
| | - Rodolphe Antoine
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne, France
| | - Philippe Dugourd
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne, France.
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27
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Morrison LJ, Rosenberg JA, Singleton JP, Brodbelt JS. Statistical Examination of the a and a + 1 Fragment Ions from 193 nm Ultraviolet Photodissociation Reveals Local Hydrogen Bonding Interactions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:1443-53. [PMID: 27206509 PMCID: PMC4974117 DOI: 10.1007/s13361-016-1418-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 05/01/2016] [Accepted: 05/06/2016] [Indexed: 05/11/2023]
Abstract
Dissociation of proteins and peptides by 193 nm ultraviolet photodissociation (UVPD) has gained momentum in proteomic studies because of the diversity of backbone fragments that are produced and subsequent unrivaled sequence coverage obtained by the approach. The pathways that form the basis for the production of particular ion types are not completely understood. In this study, a statistical approach is used to probe hydrogen atom elimination from a + 1 radical ions, and different extents of elimination are found to vary as a function of the identity of the C-terminal residue of the a product ions and the presence or absence of hydrogen bonds to the cleaved residue. Graphical Abstract ᅟ.
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Affiliation(s)
| | - Jake A Rosenberg
- Department of Chemistry, University of Texas, Austin, TX, 78712, USA
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28
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Morrison LJ, Brodbelt JS. 193 nm Ultraviolet Photodissociation Mass Spectrometry of Tetrameric Protein Complexes Provides Insight into Quaternary and Secondary Protein Topology. J Am Chem Soc 2016; 138:10849-59. [PMID: 27480400 DOI: 10.1021/jacs.6b03905] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Protein-protein interfaces and architecture are critical to the function of multiprotein complexes. Mass spectrometry-based techniques have emerged as powerful strategies for characterization of protein complexes, particularly for heterogeneous mixtures of structures. In the present study, activation and dissociation of three tetrameric protein complexes (streptavidin, transthyretin, and hemoglobin) in the gas phase was undertaken by 193 nm ultraviolet photodissociation (UVPD) for the characterization of higher order structure. High pulse energy UVPD resulted in the production of dimers and low charged monomers exhibiting symmetrical charge partitioning among the subunits (the so-called symmetrical dissociation pathways), consistent with the subunit organization of the complexes. In addition, UVPD promoted backbone cleavages of the monomeric subunits, the abundances of which corresponded to the more flexible loop regions of the proteins.
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Affiliation(s)
- Lindsay J Morrison
- Department of Chemistry, University of Texas , Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas , Austin, Texas 78712, United States
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29
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Robinson MR, Taliaferro JM, Dalby KN, Brodbelt JS. 193 nm Ultraviolet Photodissociation Mass Spectrometry for Phosphopeptide Characterization in the Positive and Negative Ion Modes. J Proteome Res 2016; 15:2739-48. [PMID: 27425180 DOI: 10.1021/acs.jproteome.6b00289] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advances in liquid chromatography tandem mass spectrometry (LC-MS/MS) have permitted phosphoproteomic analysis on a grand scale, but ongoing challenges specifically associated with confident phosphate localization continue to motivate the development of new fragmentation techniques. In the present study, ultraviolet photodissociation (UVPD) at 193 nm is evaluated for the characterization of phosphopeptides in both positive and negative ion modes. Compared to the more standard higher energy collisional dissociation (HCD), UVPD provided more extensive fragmentation with improved phosphate retention on product ions. Negative mode UVPD showed particular merit for detecting and sequencing highly acidic phosphopeptides from alpha and beta casein, but was not as robust for larger scale analysis because of lower ionization efficiencies in the negative mode. HeLa and HCC70 cell lysates were analyzed by both UVPD and HCD. While HCD identified more phosphopeptides and proteins compared to UVPD, the unique matches from UVPD analysis could be combined with the HCD data set to improve the overall depth of coverage compared to either method alone.
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Affiliation(s)
- Michelle R Robinson
- Department of Chemistry, and ‡Division of Chemical Biology and Medicinal Chemistry College of Pharmacy, The University of Texas Austin, Texas 78712, United States
| | - Juliana M Taliaferro
- Department of Chemistry, and ‡Division of Chemical Biology and Medicinal Chemistry College of Pharmacy, The University of Texas Austin, Texas 78712, United States
| | - Kevin N Dalby
- Department of Chemistry, and ‡Division of Chemical Biology and Medicinal Chemistry College of Pharmacy, The University of Texas Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, and ‡Division of Chemical Biology and Medicinal Chemistry College of Pharmacy, The University of Texas Austin, Texas 78712, United States
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30
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Halim MA, Girod M, MacAleese L, Lemoine J, Antoine R, Dugourd P. 213 nm Ultraviolet Photodissociation on Peptide Anions: Radical-Directed Fragmentation Patterns. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:474-86. [PMID: 26545767 DOI: 10.1007/s13361-015-1297-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/13/2015] [Accepted: 10/16/2015] [Indexed: 05/25/2023]
Abstract
Characterization of acidic peptides and proteins is greatly hindered due to lack of suitable analytical techniques. Here we present the implementation of 213 nm ultraviolet photodissociation (UVPD) in high-resolution quadrupole-Orbitrap mass spectrometer in negative polarity for peptide anions. Radical-driven backbone fragmentation provides 22 distinctive fragment ion types, achieving the complete sequence coverage for all reported peptides. Hydrogen-deficient radical anion not only promotes the cleavage of Cα-C bond but also stimulates the breaking of N-Cα and C-N bonds. Radical-directed loss of small molecules and specific side chain of amino acids are detected in these experiments. Radical containing side chain of amino acids (Tyr, Ser, Thr, and Asp) may possibly support the N-Cα backbone fragmentation. Proline comprising peptides exhibit the unusual fragment ions similar to reported earlier. Interestingly, basic amino acids such as Arg and Lys also stimulated the formation of abundant b and y ions of the related peptide anions. Loss of hydrogen atom from the charge-reduced radical anion and fragment ions are rationalized by time-dependent density functional theory (TDDFT) calculation, locating the potential energy surface (PES) of ππ* and repulsive πσ* excited states of a model amide system.
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Affiliation(s)
- Mohammad A Halim
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France
| | - Marion Girod
- Institut des Sciences Analytiques, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France
| | - Luke MacAleese
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France
| | - Jérôme Lemoine
- Institut des Sciences Analytiques, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France
| | - Rodolphe Antoine
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France
| | - Philippe Dugourd
- Institut Lumière Matière, Université Lyon 1 - CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France.
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31
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Shaw JB, Robinson EW, Paša-Tolić L. Vacuum Ultraviolet Photodissociation and Fourier Transform–Ion Cyclotron Resonance (FT-ICR) Mass Spectrometry: Revisited. Anal Chem 2016; 88:3019-23. [DOI: 10.1021/acs.analchem.6b00148] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Jared B. Shaw
- Environmental Molecular Sciences
Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Errol W. Robinson
- Environmental Molecular Sciences
Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Ljiljana Paša-Tolić
- Environmental Molecular Sciences
Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
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32
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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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33
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Holden DD, McGee WM, Brodbelt JS. Integration of Ultraviolet Photodissociation with Proton Transfer Reactions and Ion Parking for Analysis of Intact Proteins. Anal Chem 2015; 88:1008-16. [DOI: 10.1021/acs.analchem.5b03911] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Dustin D. Holden
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - William M. McGee
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Jennifer S. Brodbelt
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
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34
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Robotham SA, Brodbelt JS. Comparison of Ultraviolet Photodissociation and Collision Induced Dissociation of Adrenocorticotropic Hormone Peptides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:1570-9. [PMID: 26122515 DOI: 10.1007/s13361-015-1186-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 04/19/2015] [Accepted: 05/10/2015] [Indexed: 05/16/2023]
Abstract
In an effort to better characterize the fragmentation pathways promoted by ultraviolet photoexcitation in comparison to collision induced dissociation (CID), six adrenocorticotropic hormone (ACTH) peptides in a range of charge states were subjected to 266 nm ultraviolet photodissociation (UVPD), 193 nm UVPD, and CID. Similar fragment ions and distributions were observed for 266 nm UVPD and 193 nm UVPD for all peptides investigated. While both UVPD and CID led to preferential cleavage of the Y-S bond for all ACTH peptides [except ACTH (1-39)], UVPD was far less dependent on charge state and location of basic sites for the production of C-terminal and N-terminal ions. For ACTH (1-16), ACTH (1-17), ACTH (1-24), and ACTH (1-39), changes in the distributions of fragment ion types (a, b, c, x, y, z, and collectively N-terminal ions versus C-terminal ions) showed only minor changes upon UVPD for all charge states. In contrast, CID displayed significant changes in the fragment ion type distributions as a function of charge state, an outcome consistent with the dependence on the number and location of mobile protons that is not prominent for UVPD. Sequence coverages obtained by UVPD showed less dependence on charge state than those determined by CID, with the latter showing a consistent decrease in coverage as charge state increased.
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Affiliation(s)
- Scott A Robotham
- Department of Chemistry, University of Texas, Austin, TX, 78712, USA
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35
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Levy MJ, Gucinski AC, Boyne MT. Primary Sequence Confirmation of a Protein Therapeutic Using Top Down MS/MS and MS3. Anal Chem 2015; 87:6995-9. [DOI: 10.1021/acs.analchem.5b01113] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Michaella J. Levy
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of
Testing and Research, Division of Pharmaceutical Analysis, 645 S. Newstead Ave., St. Louis, Missouri 63110, United States
| | - Ashley C. Gucinski
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of
Testing and Research, Division of Pharmaceutical Analysis, 645 S. Newstead Ave., St. Louis, Missouri 63110, United States
| | - Michael T. Boyne
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of
Testing and Research, Division of Pharmaceutical Analysis, 645 S. Newstead Ave., St. Louis, Missouri 63110, United States
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36
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Kopysov V, Makarov A, Boyarkin OV. Colors for Molecular Masses: Fusion of Spectroscopy and Mass Spectrometry for Identification of Biomolecules. Anal Chem 2015; 87:4607-11. [DOI: 10.1021/acs.analchem.5b00822] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Vladimir Kopysov
- Laboratoire
de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Alexander Makarov
- Thermo Fisher Scientific, Hanna-Kunath
Strasse 11, 28199 Bremen, Germany
| | - Oleg V. Boyarkin
- Laboratoire
de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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37
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Moon JH, Yoon S, Bae YJ, Kim MS. Formation of gas-phase peptide ions and their dissociation in MALDI: insights from kinetic and ion yield studies. MASS SPECTROMETRY REVIEWS 2015; 34:94-115. [PMID: 24863621 DOI: 10.1002/mas.21427] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 03/17/2014] [Indexed: 06/03/2023]
Abstract
Insights on mechanisms for the generation of gas-phase peptide ions and their dissociation in matrix-assisted laser desorption ionization (MALDI) gained from the kinetic and ion yield studies are presented. Even though the time-resolved photodissociation technique was initially used to determine the dissociation kinetics of peptide ions and their effective temperature, it was replaced by a simpler method utilizing dissociation yields from in-source decay (ISD) and post-source decay (PSD). The ion yields for a matrix and a peptide were measured by repeatedly irradiating a region on a sample and collecting ion signals until the sample in the region was completely depleted. Matrix- and peptide-derived gas-phase cations were found to be generated by pre-formed ion emission or by ion-pair emission followed by anion loss, but not by laser-induced ionization. The total number of ions, that is, matrix plus peptide, was found to be equal to the number of ions emitted from a pure matrix. A matrix plume was found to cool as it expanded, from around 800-1,000 K to 400-500 K. Dissociation of peptide ions along b/y channels was found to occur statistically, that is, following RRKM behavior. Small critical energy (E0 = 0.6-0.7 eV) and highly negative critical entropy (ΔS(‡) = -30 to -25 eu) suggested that the transition structure was stabilized by multiple intramolecular interactions.
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Affiliation(s)
- Jeong Hee Moon
- Medical Proteomics Research Center, KRIBB, Daejeon, 305-806, Korea
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38
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Doll S, Burlingame AL. Mass spectrometry-based detection and assignment of protein posttranslational modifications. ACS Chem Biol 2015; 10:63-71. [PMID: 25541750 PMCID: PMC4301092 DOI: 10.1021/cb500904b] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Recent
advances in mass spectrometry (MS)-based proteomics allow
the identification and quantitation of thousands of posttranslational
modification (PTM) sites in a single experiment. This follows from
the development of more effective class enrichment strategies, new
high performance instrumentation and bioinformatic algorithms with
rigorous scoring strategies. More widespread use of these combined
capabilities have led to a vast expansion in our knowledge of the
complexity of biological processes mediated by PTMs. The classes most
actively pursued include phosphorylation, ubiquitination, O-GlcNAcylation,
methylation, and acetylation. Very recently succinylation, SUMOylation,
and citrullination have emerged. Among the some 260 000 PTM
sites that have been identified in the human proteome thus far, only
a few have been assigned to key regulatory and/or other biological
roles. Here, we provide an update of MS-based PTM analyses, with a
focus on current enrichment strategies coupled with revolutionary
advances in high performance MS. Furthermore, we discuss examples
of the discovery of recently described biological roles of PTMs and
address the challenges of defining site-specific functions.
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Affiliation(s)
- Sophia Doll
- Department
of Pharmaceutical Chemistry, University of California, San Francisco, California 94158-2517, United States
- Department
of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, 82152, Germany
| | - Alma L. Burlingame
- Department
of Pharmaceutical Chemistry, University of California, San Francisco, California 94158-2517, United States
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39
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Canon F, Milosavljević AR, Nahon L, Giuliani A. Action spectroscopy of a protonated peptide in the ultraviolet range. Phys Chem Chem Phys 2015; 17:25725-33. [DOI: 10.1039/c4cp04762a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Action spectroscopy of substance P, a model undecapeptide, has been probed from 5.2 eV to 20 eV.
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Affiliation(s)
- Francis Canon
- Synchrotron Soleil
- l'Orme des Merisiers
- 91192 Gif sur Yvette Cedex
- France
- UMR1324 Centre des Sciences du Goût et de l'Alimentation
| | | | - Laurent Nahon
- Synchrotron Soleil
- l'Orme des Merisiers
- 91192 Gif sur Yvette Cedex
- France
| | - Alexandre Giuliani
- Synchrotron Soleil
- l'Orme des Merisiers
- 91192 Gif sur Yvette Cedex
- France
- Uar1008
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40
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Hoffmann WD, Jackson GP. Charge transfer dissociation (CTD) mass spectrometry of peptide cations using kiloelectronvolt helium cations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:1939-43. [PMID: 25231159 DOI: 10.1007/s13361-014-0989-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/23/2014] [Accepted: 07/27/2014] [Indexed: 05/04/2023]
Abstract
A kiloelectronvolt beam of helium ions is used to ionize and fragment precursor peptide ions starting in the 1+ charge state. The electron affinity of helium cations (24.6 eV) exceeds the ionization potential of protonated peptides and can therefore be used to abstract an electron from--or charge exchange with--the isolated precursor ions. Kiloelectronvolt energies are used, (1) to overcome the Coulombic repulsion barrier between the cationic reactants, (2) to overcome ion-defocussing effects in the ion trap, and (3) to provide additional activation energy. Charge transfer dissociation (CTD) of the [M+H](+) precursor of Substance P gives product ions such as [M+H](2+•) and a dominant series of a ions in both the 1+ and 2+ charge states. These observations, along with the less-abundant a + 1 ions, are consistent with ultraviolet photodissociation (UVPD) results of others and indicate that C-C(α) cleavages are possible through charge exchange with helium ions. Although the efficiencies and timescale of CTD are not yet suitable for on-line chromatography, this new approach to ion activation provides an additional potential tool for the interrogation of gas phase ions.
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Affiliation(s)
- William D Hoffmann
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, WV, 26506, USA
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41
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Giuliani A, Milosavljević AR, Canon F, Nahon L. Contribution of synchrotron radiation to photoactivation studies of biomolecular ions in the gas phase. MASS SPECTROMETRY REVIEWS 2014; 33:424-441. [PMID: 24375654 DOI: 10.1002/mas.21398] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Photon activation of ions in the visible and ultraviolet range attracts a growing interest, partly for its promising applications in tandem mass spectrometry. However, this task is not trivial, as it requires notably high brilliance photon sources. Hence, most of the work in that field has been performed using lasers. Synchrotron radiation is a source continuously tunable over a wide photon energy range and which possesses the necessary characteristics for ion activation. This review focuses on the array of applications of synchrotron radiation in photon activation of ions ranging from near UV to soft X-rays.
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Affiliation(s)
- Alexandre Giuliani
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, 91192, Gif-sur-Yvette, France; UAR1008 CEPIA, INRA, 44316, Nantes, France
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42
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Brodbelt JS. Photodissociation mass spectrometry: new tools for characterization of biological molecules. Chem Soc Rev 2014; 43:2757-83. [PMID: 24481009 PMCID: PMC3966968 DOI: 10.1039/c3cs60444f] [Citation(s) in RCA: 232] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Photodissociation mass spectrometry combines the ability to activate and fragment ions using photons with the sensitive detection of the resulting product ions by mass spectrometry. This combination affords a versatile tool for characterization of biological molecules. The scope and breadth of photodissociation mass spectrometry have increased substantially over the past decade as new research groups have entered the field and developed a number of innovative applications that illustrate the ability of photodissociation to produce rich fragmentation patterns, to cleave bonds selectively, and to target specific molecules based on incorporation of chromophores. This review focuses on many of the key developments in photodissociation mass spectrometry over the past decade with a particular emphasis on its applications to biological molecules.
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43
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Thomas DA, Sohn CH, Gao J, Beauchamp JL. Hydrogen Bonding Constrains Free Radical Reaction Dynamics at Serine and Threonine Residues in Peptides. J Phys Chem A 2014; 118:8380-92. [DOI: 10.1021/jp501367w] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Daniel A. Thomas
- Arthur Amos Noyes Laboratory
of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Chang Ho Sohn
- Arthur Amos Noyes Laboratory
of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - Jinshan Gao
- Arthur Amos Noyes Laboratory
of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
| | - J. L. Beauchamp
- Arthur Amos Noyes Laboratory
of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States
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44
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Cannon JR, Cammarata M, Robotham SA, Cotham VC, Shaw JB, Fellers RT, Early BP, Thomas PM, Kelleher NL, Brodbelt JS. Ultraviolet photodissociation for characterization of whole proteins on a chromatographic time scale. Anal Chem 2014; 86:2185-92. [PMID: 24447299 PMCID: PMC3958131 DOI: 10.1021/ac403859a] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/21/2014] [Indexed: 02/01/2023]
Abstract
Intact protein characterization using mass spectrometry thus far has been achieved at the cost of throughput. Presented here is the application of 193 nm ultraviolet photodissociation (UVPD) for top down identification and characterization of proteins in complex mixtures in an online fashion. Liquid chromatographic separation at the intact protein level coupled with fast UVPD and high-resolution detection resulted in confident identification of 46 unique sequences compared to 44 using HCD from prepared Escherichia coli ribosomes. Importantly, nearly all proteins identified in both the UVPD and optimized HCD analyses demonstrated a substantial increase in confidence in identification (as defined by an average decrease in E value of ∼40 orders of magnitude) due to the higher number of matched fragment ions. Also shown is the potential for high-throughput characterization of intact proteins via liquid chromatography (LC)-UVPD-MS of molecular weight-based fractions of a Saccharomyces cerevisiae lysate. In total, protein products from 215 genes were identified and found in 292 distinct proteoforms, 168 of which contained some type of post-translational modification.
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Affiliation(s)
- Joe R. Cannon
- Department
of Chemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, United States
| | - Michael
B. Cammarata
- Department
of Chemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, United States
| | - Scott A. Robotham
- Department
of Chemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, United States
| | - Victoria C. Cotham
- Department
of Chemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, United States
| | - Jared B. Shaw
- Department
of Chemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, United States
| | - Ryan T. Fellers
- Departments
of Chemistry and Molecular Biosciences and the Proteomics Center of
Excellence, Northwestern University, Evanston, Illinois 60208, United States
| | - Bryan P. Early
- Departments
of Chemistry and Molecular Biosciences and the Proteomics Center of
Excellence, Northwestern University, Evanston, Illinois 60208, United States
| | - Paul M. Thomas
- Departments
of Chemistry and Molecular Biosciences and the Proteomics Center of
Excellence, Northwestern University, Evanston, Illinois 60208, United States
| | - Neil L. Kelleher
- Departments
of Chemistry and Molecular Biosciences and the Proteomics Center of
Excellence, Northwestern University, Evanston, Illinois 60208, United States
| | - Jennifer S. Brodbelt
- Department
of Chemistry, University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, United States
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45
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Webber N, He Y, Reilly JP. 157 nm photodissociation of dipeptide ions containing N-terminal arginine. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:196-203. [PMID: 24310819 DOI: 10.1007/s13361-013-0762-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/24/2013] [Accepted: 09/25/2013] [Indexed: 06/02/2023]
Abstract
Twenty singly-charged dipeptide ions with N-terminal arginine were photodissociated using 157 nm light in both a linear ion-trap mass spectrometer and a MALDI-TOF-TOF mass spectrometer. Analogous to previous work on dipeptides containing C-terminal arginine, this set of samples enabled insights into the photofragmentation propensities associated with individual residues. In addition to familiar products such as a-, d-, and immonium ions, m2 and m2+13 ions were also observed. Certain side chains tended to cleave between their β and γ carbons without necessarily forming d- or w-type ions, and a few other ions were produced by the high-energy fragmentation of multiple bonds.
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Affiliation(s)
- Nathaniel Webber
- Department of Chemistry, Indiana University, Bloomington, IN, 47405, USA
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Janve BA, Yang W, Marshall MR, Reyes-De-Corcuera JI, Rababah TM. Nonthermal inactivation of soy (Glycine max Sp.) lipoxygenase by pulsed ultraviolet light. J Food Sci 2014; 79:C8-C18. [PMID: 24460768 DOI: 10.1111/1750-3841.12317] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 10/21/2013] [Indexed: 01/03/2023]
Abstract
This study investigated pulsed ultraviolet (PUV) illumination at different distances from the PUV source on soybean lipoxygenase (LOX) (0.4 mg/mL in 0.01 M Tris-HCl buffer, pH 9) activity. Samples (5 mL) were illuminated for 1, 2, 4, 8, and 16 s at 3 distances 6, 8.5, and 11 cm from the PUV lamp's quartz window. The temperature of 33.5 ± 1.8°C was observed for the highest treatment time of 16 s at the shortest distance of 6 cm, and resulted in a 3.5 log reduction (99.95%) in initial LOX activity. Illumination time and distance from the lamp significantly (P ≤ 0.05) affected LOX inactivation. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was performed on treated LOX samples and further protein profile for treated LOX filtrate (≤10 kDa), was analyzed by reverse phase high-performance liquid chromatography (RP-HPLC). The protein profile analysis revealed that LOX protein degradation was influenced significantly (P ≤ 0.05) by PUV illumination time.
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Affiliation(s)
- Bhaskar A Janve
- Dept. of Food Science and Human Nutrition, Univ. of Florida, Gainesville, FL, 32611, U.S.A
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He Y, Webber N, Reilly JP. 157 nm photodissociation of a complete set of dipeptide ions containing C-terminal arginine. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2013; 24:675-683. [PMID: 23378257 DOI: 10.1007/s13361-012-0514-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 07/17/2012] [Accepted: 07/18/2012] [Indexed: 06/01/2023]
Abstract
Twenty singly-charged dipeptide ions with C-terminal arginine were photodissociated with 157 nm light and their tandem mass spectra recorded. Many of the small product ions that were observed are standard peptide fragments that have been commonly seen in VUV photodissociation studies. However, the study of a library of dipeptides containing all 20 N-terminal amino acids enabled the recognition of trends associated with the occurrence of w-, v-, and immonium ions, the observation of competition between forming N- and C-terminal fragments in dipeptide RR, and the identification of some unusual fragment ions appearing at masses of 183, 187, 196, and 197 Da. A highly accurate internal calibration of the photodissociation TOF-TOF data enabled molecular formulae for these four product ions to be derived. Their proposed structures reflect the rather high-energy nature of this fragmentation phenomenon.
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Affiliation(s)
- Yi He
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
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He Y, Parthasarathi R, Raghavachari K, Reilly JP. Photodissociation of charge tagged peptides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:1182-1190. [PMID: 22532332 DOI: 10.1007/s13361-012-0379-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 02/29/2012] [Accepted: 03/16/2012] [Indexed: 05/31/2023]
Abstract
Tris(2,4,6-trimethoxyphenyl) phosphonium acetyl (TMPP-Ac) was previously introduced to improve the mass spectrometric sequence analysis of peptides by fixing a permanent charge at the N-termini. However, peptides containing arginine residues did not fragment efficiently after TMPP-Ac modification. In this work, we combine charge derivatization with photodissociation. The fragmentation of TMPP-derivatized peptides is greatly improved and a series of N-terminal fragments is generated with complete sequence information. Arginine has a special effect on the fragmentation of the TMPP tagged peptides when it is the N-terminal peptide residue. Theoretical and experimental results suggest that this is due to hydrogen transfer from the charged N-terminus to the hydrogen-deficient peptide sequence.
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Affiliation(s)
- Yi He
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
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Madsen JA, Cheng RR, Kaoud TS, Dalby KN, Makarov DE, Brodbelt JS. Charge-site-dependent dissociation of hydrogen-rich radical peptide cations upon vacuum UV photoexcitation. Chemistry 2012; 18:5374-83. [PMID: 22431222 DOI: 10.1002/chem.201103534] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Indexed: 11/06/2022]
Abstract
Here, 193 nm vacuum ultraviolet photodissociation (VUVPD) was used to investigate the fragmentation of hydrogen-rich radical peptide cations generated by electron transfer reactions. VUVPD offers new insight into the factors that drive radical- and photon-directed processes. The location of a basic Arg site influences photon-activated C(α)-C(O) bond cleavages of singly charged peptide radical cations, an outcome attributed to the initial conformation of the peptide as supported by molecular dynamics simulated annealing and the population of excited states upon UV excitation. This hybrid ETD/VUVPD method was employed to identify phosphorylation sites of the kinase domain of human TRPM7/ChaK1.
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Affiliation(s)
- James A Madsen
- Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712, USA
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Robinson MR, Madsen JA, Brodbelt JS. 193 nm ultraviolet photodissociation of imidazolinylated Lys-N peptides for de novo sequencing. Anal Chem 2012; 84:2433-9. [PMID: 22283738 DOI: 10.1021/ac203227y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The goal of many MS/MS de novo sequencing strategies is to generate a single product ion series that can be used to determine the precursor ion sequence. Most methods fall short of achieving such simplified spectra, and the presence of additional ion series impede peptide identification. The present study aims to solve the problem of confounding ion series by enhancing the formation of "golden" sets of a, b, and c ions for sequencing. Taking advantage of the characteristic mass differences between the golden ions allows N-terminal fragments to be readily identified while other ion series are excluded. By combining the use of Lys-N, an alternate protease, to produce peptides with lysine residues at each N-terminus with subsequent imidazolinylation of the ε-amino group of each lysine, peptides with highly basic sites localized at each N-terminus are generated. Subsequent MS/MS analysis by using 193 nm ultraviolet photodissociation (UVPD) results in enhanced formation of the diagnostic golden pairs and golden triplets that are ideal for de novo sequencing.
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Affiliation(s)
- Michelle R Robinson
- Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, USA
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