1
|
Macias LA, Brodbelt JS. Investigation of Product Ions Generated by 193 nm Ultraviolet Photodissociation of Peptides and Proteins Containing Disulfide Bonds. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:1315-1324. [PMID: 35736955 DOI: 10.1021/jasms.2c00124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Disulfide bridges are unique post-translational modifications (PTM) that contribute to protein architecture and modulate function. This PTM, however, challenges top-down mass spectrometry by cyclizing stretches of the protein sequence. In order to produce and release detectable product ions that contribute to the assignment of proteoforms, regions of a protein encapsulated by disulfide bonds require two fragmentation events: cleavage of the protein backbone and cleavage of the disulfide bond. Traditional collisional activation methods do not cleave disulfide bonds efficiently, often leading to low sequence coverage of proteins that incorporate this feature. To address this challenge, we have evaluated the fragmentation pathways enabled by 193 nm ultraviolet photodissociation (UVPD) and UVPD coupled to electron transfer dissociation for the characterization of protein structures incorporating disulfide bonds. Cleavage of disulfide bonds by either approach results in S-S and C-S dissociation products that result from a combination of homolytic cleavage and hydrogen-transfer processes. Characterization of these product ions elevates interpretation of complex top-down spectra of proteins that incorporate disulfide bonds.
Collapse
Affiliation(s)
- Luis A Macias
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| |
Collapse
|
2
|
Zhou M, Lantz C, Brown KA, Ge Y, Paša-Tolić L, Loo JA, Lermyte F. Higher-order structural characterisation of native proteins and complexes by top-down mass spectrometry. Chem Sci 2020; 11:12918-12936. [PMID: 34094482 PMCID: PMC8163214 DOI: 10.1039/d0sc04392c] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 10/05/2020] [Indexed: 12/11/2022] Open
Abstract
In biology, it can be argued that if the genome contains the script for a cell's life cycle, then the proteome constitutes an ensemble cast of actors that brings these instructions to life. Their interactions with each other, co-factors, ligands, substrates, and so on, are key to understanding nearly any biological process. Mass spectrometry is well established as the method of choice to determine protein primary structure and location of post-translational modifications. In recent years, top-down fragmentation of intact proteins has been increasingly combined with ionisation of noncovalent assemblies under non-denaturing conditions, i.e., native mass spectrometry. Sequence, post-translational modifications, ligand/metal binding, protein folding, and complex stoichiometry can thus all be probed directly. Here, we review recent developments in this new and exciting field of research. While this work is written primarily from a mass spectrometry perspective, it is targeted to all bioanalytical scientists who are interested in applying these methods to their own biochemistry and chemical biology research.
Collapse
Affiliation(s)
- Mowei Zhou
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory Richland WA 99354 USA
| | - Carter Lantz
- Department of Chemistry and Biochemistry, Department of Biological Chemistry, University of California-Los Angeles Los Angeles CA 90095 USA
| | - Kyle A Brown
- Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison Madison WI 53706 USA
| | - Ljiljana Paša-Tolić
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory Richland WA 99354 USA
| | - Joseph A Loo
- Department of Chemistry and Biochemistry, Department of Biological Chemistry, University of California-Los Angeles Los Angeles CA 90095 USA
| | - Frederik Lermyte
- Department of Chemistry, Institute of Chemistry and Biochemistry, Technical University of Darmstadt 64287 Darmstadt Germany
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège 4000 Liège Belgium
- School of Engineering, University of Warwick Coventry CV4 7AL UK
| |
Collapse
|
3
|
Affiliation(s)
| | | | - Jennifer S. Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| |
Collapse
|
4
|
Shaw JB, Liu W, Vasil′ev YV, Bracken CC, Malhan N, Guthals A, Beckman JS, Voinov VG. Direct Determination of Antibody Chain Pairing by Top-down and Middle-down Mass Spectrometry Using Electron Capture Dissociation and Ultraviolet Photodissociation. Anal Chem 2020; 92:766-773. [PMID: 31769659 PMCID: PMC7819135 DOI: 10.1021/acs.analchem.9b03129] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
One challenge associated with the discovery and development of monoclonal antibody (mAb) therapeutics is the determination of heavy chain and light chain pairing. Advances in MS instrumentation and MS/MS methods have greatly enhanced capabilities for the analysis of large intact proteins yielding much more detailed and accurate proteoform characterization. Consequently, direct interrogation of intact antibodies or F(ab')2 and Fab fragments has the potential to significantly streamline therapeutic mAb discovery processes. Here, we demonstrate for the first time the ability to efficiently cleave disulfide bonds linking heavy and light chains of mAbs using electron capture dissociation (ECD) and 157 nm ultraviolet photodissociation (UVPD). The combination of intact mAb, Fab, or F(ab')2 mass, intact LC and Fd masses, and CDR3 sequence coverage enabled determination of heavy chain and light chain pairing from a single experiment and experimental condition. These results demonstrate the potential of top-down and middle-down proteomics to significantly streamline therapeutic antibody discovery.
Collapse
Affiliation(s)
- Jared B. Shaw
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 3335 Innovation Boulevard, Richland, Washington 99354, United States
| | - Weijing Liu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 3335 Innovation Boulevard, Richland, Washington 99354, United States
| | - Yury V. Vasil′ev
- e-MSion Inc., 2121 NE Jack London Drive, Corvallis, Oregon 97330, United States
- Linus Pauling Institute and the Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331, United States
| | - Carter C. Bracken
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 3335 Innovation Boulevard, Richland, Washington 99354, United States
| | - Neha Malhan
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 3335 Innovation Boulevard, Richland, Washington 99354, United States
| | - Adrian Guthals
- Mapp Biopharmaceutical Inc., 6160 Lusk Boulevard #105, San Diego, California 92121, United States
| | - Joseph S. Beckman
- e-MSion Inc., 2121 NE Jack London Drive, Corvallis, Oregon 97330, United States
- Linus Pauling Institute and the Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331, United States
| | - Valery G. Voinov
- e-MSion Inc., 2121 NE Jack London Drive, Corvallis, Oregon 97330, United States
- Linus Pauling Institute and the Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331, United States
| |
Collapse
|
5
|
Adhikari S, Xia Y, McLuckey SA. Top-Down Analysis of Disulfide-Linked Proteins Using Photoinduced Radical Reactions and ET-DDC. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2019; 444:116173. [PMID: 31372092 PMCID: PMC6675022 DOI: 10.1016/j.ijms.2019.06.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Top-down characterization of proteins via tandem mass spectrometry (MS/MS) can be challenging due to the presence of multiple disulfide bond linkages; which significantly inhibit the backbone cleavage efficiency for the formation of structurally informative fragment ions. In this study, we present a strategy of pairing a solution-phase photoinitiating system with dipolar direct current induced collisional activation of electron transfer products (ET-DDC) of proteins for a top-down MS/MS approach. The photoinitiating system allows for a rapid scission of all the disulfide linkages in the protein (on the time scale of seconds) with high efficiency (near to complete reduction); while ET-DDC collisional activation improves the fragmentation efficiency for the protein via broadband activation of all the first-generation charge reduced precursor ions (e.g., electron transfer no-dissociation or ETnoD products) from electron transfer reactions over a wide mass-to-charge range. As a result, this approach enabled the generation of extensive sequence informative fragment ion yields for a rapid and enhanced structural characterization of disulfide-linked proteins.
Collapse
Affiliation(s)
- Sarju Adhikari
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Yu Xia
- Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Scott A. McLuckey
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
- Address reprint requests to: Dr. Scott A. McLuckey, 560 Oval Drive, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084, USA, Phone: (765) 494-5270, Fax: (765) 494-0239,
| |
Collapse
|
6
|
Adhikari S, Yang X, Xia Y. Acetone/Isopropanol Photoinitiating System Enables Tunable Disulfide Reduction and Disulfide Mapping via Tandem Mass Spectrometry. Anal Chem 2018; 90:13036-13043. [PMID: 30350608 PMCID: PMC6310128 DOI: 10.1021/acs.analchem.8b04019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Herein, we report the development of a new photochemical system which enables rapid and tunable disulfide bond reduction and its application in disulfide mapping via online coupling with mass spectrometry (MS). Acetone, a clean and electrospray ionization (ESI) compatible solvent, is used as the photoinitiator (1% volume) in the solvent system consisting of 1:1 alkyl alcohol and water. Under ultraviolet (UV) irradiation (∼254 nm), the acetone/alcohol system produces hydroxyalkyl radicals, which are responsible for disulfide bond cleavage in peptides. Acetone/isopropanol is most suitable for optimizing the disulfide reduction products, leading to almost complete conversion in less than 5 s when the reaction is conducted in a flow microreactor. The flow microreactor device not only facilitates direct coupling with ESI-MS but also allows fine-tuning of the extent of disulfide reduction by varying the UV exposure time. Near full sequence coverage for peptides consisting of intra- or interchain disulfide bonds has been achieved from complete disulfide reduction and online tandem mass spectrometry (MS/MS) via low energy collision-induced dissociation. Coupling different degrees of partial disulfide reduction with ESI-MS/MS allows disulfide mapping as demonstrated for characterizing the three disulfide bonds in insulin.
Collapse
Affiliation(s)
- Sarju Adhikari
- Department of Chemistry, MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
| | - Xiaoyue Yang
- Department of Chemistry, MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing 100084, China
| | - Yu Xia
- Department of Chemistry, MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, United States
| |
Collapse
|
7
|
Quick MM, Crittenden CM, Rosenberg JA, Brodbelt JS. Characterization of Disulfide Linkages in Proteins by 193 nm Ultraviolet Photodissociation (UVPD) Mass Spectrometry. Anal Chem 2018; 90:8523-8530. [PMID: 29902373 PMCID: PMC6050148 DOI: 10.1021/acs.analchem.8b01556] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Deciphering disulfide bond patterns in proteins remains a significant challenge. In the present study, interlinked disulfide bonds connecting peptide chains are homolytically cleaved with 193 nm ultraviolet photodissociation (UVPD). Analysis of insulin showcased the ability of UVPD to cleave multiple disulfide bonds and provide sequence coverage of the peptide chains in the same MS/MS event. For proteins containing more complex disulfide bonding patterns, an approach combining partial reduction and alkylation mitigated disulfide scrambling and allowed assignment of the array of disulfide bonds. The 4 disulfide bonds of lysozyme and the 19 disulfide bonds of serotransferrin were characterized through LC/UVPD-MS analysis of nonreduced and partially reduced protein digests.
Collapse
|
8
|
Durand KL, Tan L, Stinson CA, Love-Nkansah CB, Ma X, Xia Y. Assigning Peptide Disulfide Linkage Pattern Among Regio-Isomers via Methoxy Addition to Disulfide and Tandem Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1099-1108. [PMID: 28194735 DOI: 10.1007/s13361-017-1595-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 06/06/2023]
Abstract
Pinpointing disulfide linkage pattern is critical in the characterization of proteins and peptides consisting of multiple disulfide bonds. Herein, we report a method based on coupling online disulfide modification and tandem mass spectrometry (MS/MS) to distinguish peptide disulfide regio-isomers. Such a method relies on a new disulfide bond cleavage reaction in solution, involving methanol as a reactant and 254 nm ultraviolet (UV) irradiation. This reaction leads to selective cleavage of a disulfide bond and formation of sulfenic methyl ester (-SOCH3) at one cysteine residue and a thiol (-SH) at the other. Under low energy collision-induced dissociation (CID), cysteine sulfenic methyl ester motif produces a signature methanol loss (-32 Da), allowing its identification from other possible isomeric structures such as S-hydroxylmethyl (-SCH2OH) and methyl sulfoxide (-S(O)-CH3). Since disulfide bond can be selectively cleaved and modified upon methoxy addition, subsequent MS2 CID of the methoxy addition product provides enhanced sequence coverage as demonstrated by the analysis of bovine insulin. More importantly, this reaction does not induce disulfide scrambling, likely due to the fact that radical intermediates are not involved in the process. An approach based on methoxy addition followed by MS3 CID has been developed for assigning disulfide linkage patterns in peptide disulfide regio-isomers. This methodology was successfully applied to characterizing peptide systems having two disulfide bonds and three disulfide linkage isomers: side-by-side, overlapped, and looped-within-a-loop configurations. Graphical Abstract ᅟ.
Collapse
Affiliation(s)
- Kirt L Durand
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907-2084, USA
| | - Lei Tan
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907-2084, USA
| | - Craig A Stinson
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907-2084, USA
| | | | - Xiaoxiao Ma
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907-2084, USA
| | - Yu Xia
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907-2084, USA.
| |
Collapse
|
9
|
Holden DD, Makarov A, Schwartz JC, Sanders JD, Zhuk E, Brodbelt JS. Ultraviolet Photodissociation Induced by Light‐Emitting Diodes in a Planar Ion Trap. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Dustin D. Holden
- Department of Chemistry The University of Texas at Austin 105 E. 24th St Austin TX 78712 USA
| | - Alexander Makarov
- Thermo Fisher Scientific (Bremen) GmbH Hanna-Kunath-Strasse 11 28199 Bremen Germany
| | - Jae C. Schwartz
- Thermo Fisher Scientific Inc. 355 River Oaks Pkwy San Jose CA 95134 USA
| | - James D. Sanders
- Department of Chemistry The University of Texas at Austin 105 E. 24th St Austin TX 78712 USA
| | - Eugene Zhuk
- Thermo Fisher Scientific Inc. 355 River Oaks Pkwy San Jose CA 95134 USA
| | - Jennifer S. Brodbelt
- Department of Chemistry The University of Texas at Austin 105 E. 24th St Austin TX 78712 USA
| |
Collapse
|
10
|
Holden DD, Makarov A, Schwartz JC, Sanders JD, Zhuk E, Brodbelt JS. Ultraviolet Photodissociation Induced by Light-Emitting Diodes in a Planar Ion Trap. Angew Chem Int Ed Engl 2016; 55:12417-21. [PMID: 27605434 DOI: 10.1002/anie.201605850] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/02/2016] [Indexed: 11/09/2022]
Abstract
The first application of light-emitting diodes (LEDs) for ultraviolet photodissociation (UVPD) mass spectrometry is reported. LEDs provide a compact, low cost light source and have been incorporated directly into the trapping cell of an Orbitrap mass spectrometer. MS/MS efficiencies of over 50 % were obtained using an extended irradiation period, and UVPD was optimized by modulating the ion trapping parameters to maximize the overlap between the ion cloud and the irradiation volume.
Collapse
Affiliation(s)
- Dustin D Holden
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th St, Austin, TX, 78712, USA
| | - Alexander Makarov
- Thermo Fisher Scientific (Bremen) GmbH, Hanna-Kunath-Strasse 11, 28199, Bremen, Germany
| | - Jae C Schwartz
- Thermo Fisher Scientific Inc., 355 River Oaks Pkwy, San Jose, CA, 95134, USA
| | - James D Sanders
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th St, Austin, TX, 78712, USA
| | - Eugene Zhuk
- Thermo Fisher Scientific Inc., 355 River Oaks Pkwy, San Jose, CA, 95134, USA
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th St, Austin, TX, 78712, USA.
| |
Collapse
|
11
|
Massonnet P, Upert G, Smargiasso N, Gilles N, Quinton L, De Pauw E. Combined Use of Ion Mobility and Collision-Induced Dissociation To Investigate the Opening of Disulfide Bridges by Electron-Transfer Dissociation in Peptides Bearing Two Disulfide Bonds. Anal Chem 2015; 87:5240-6. [DOI: 10.1021/acs.analchem.5b00245] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Philippe Massonnet
- Laboratory of
Mass Spectrometry, Department of Chemistry, GIGA-R, University of Liege, Allée de la Chimie 3, B-4000 Liege, Belgium
| | - Gregory Upert
- Commissariat
à
l’Energie Atomique, DSV/iBiTec-S/SIMOPRO, F91191 Gif-sur-Yvette, France
| | - Nicolas Smargiasso
- Laboratory of
Mass Spectrometry, Department of Chemistry, GIGA-R, University of Liege, Allée de la Chimie 3, B-4000 Liege, Belgium
| | - Nicolas Gilles
- Commissariat
à
l’Energie Atomique, DSV/iBiTec-S/SIMOPRO, F91191 Gif-sur-Yvette, France
| | - Loïc Quinton
- Laboratory of
Mass Spectrometry, Department of Chemistry, GIGA-R, University of Liege, Allée de la Chimie 3, B-4000 Liege, Belgium
| | - Edwin De Pauw
- Laboratory of
Mass Spectrometry, Department of Chemistry, GIGA-R, University of Liege, Allée de la Chimie 3, B-4000 Liege, Belgium
| |
Collapse
|
12
|
Stinson CA, Xia Y. Radical induced disulfide bond cleavage within peptides via ultraviolet irradiation of an electrospray plume. Analyst 2013; 138:2840-6. [DOI: 10.1039/c3an00303e] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
13
|
Yin BC, You M, Tan W, Ye BC. Mercury(II) ion detection via pyrene-mediated photolysis of disulfide bonds. Chemistry 2012; 18:1286-9. [PMID: 22223216 DOI: 10.1002/chem.201103348] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 12/12/2011] [Indexed: 11/07/2022]
Affiliation(s)
- Bin-Cheng Yin
- State Key Laboratory of Bioreactor Engineering, East China University of Science & Technology, Shanghai, 200237, P.R. China
| | | | | | | |
Collapse
|
14
|
Lee M, Lee Y, Kang M, Park H, Seong Y, Sung BJ, Moon B, Oh HB. Disulfide bond cleavage in TEMPO-free radical initiated peptide sequencing mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2011; 46:830-839. [PMID: 21834022 DOI: 10.1002/jms.1955] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The gas-phase free radical initiated peptide sequencing (FRIPS) fragmentation behavior of o-TEMPO-Bz-conjugated peptides with an intra- and intermolecular disulfide bond was investigated using MS(n) tandem mass spectrometry experiments. Investigated peptides included four peptides with an intramolecular cyclic disulfide bond, Bactenecin (RLCRIVVIRVCR), TGF-α (CHSGYVGVRC), MCH (DFDMLRCMLGRVFRPCWQY) and Adrenomedullin (16-31) (CRFGTCTVQKLAHQIY), and two peptides with an intermolecular disulfide bond. Collisional activation of the benzyl radical conjugated peptide cation, which was generated through the release of a TEMPO radical from o-TEMPO-Bz-conjugated peptides upon initial collisional activation, produced a large number of peptide backbone fragments in which the S-S or C-S bond was readily cleaved. The observed peptide backbone fragments included a-, c-, x- or z-types, which indicates that the radical-driven peptide fragmentation mechanism plays an important role in TEMPO-FRIPS mass spectrometry. FRIPS application of the linearly linked disulfide peptides further showed that the S-S or C-S bond was selectively and preferentially cleaved, followed by peptide backbone dissociations. In the FRIPS mass spectra, the loss of •SH or •SSH was also abundantly found. On the basis of these findings, FRIPS fragmentation pathways for peptides with a disulfide bond are proposed. For the cleavage of the S-S bond, the abstraction of a hydrogen atom at C(β) by the benzyl radical is proposed to be the initial radical abstraction/transfer reaction. On the other hand, H-abstraction at C(α) is suggested to lead to C-S bond cleavage, which yields [ion ± S] fragments or the loss of •SH or •SSH.
Collapse
Affiliation(s)
- Minhee Lee
- Department of Chemistry, Sogang University, Seoul 121-742, Korea
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Park S, Ahn WK, Lee S, Han SY, Rhee BK, Oh HB. Ultraviolet photodissociation at 266 nm of phosphorylated peptide cations. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2009; 23:3609-3620. [PMID: 19890956 DOI: 10.1002/rcm.4184] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Ultraviolet (UV) photodissociation (PD) experiments using 266 nm light were performed for a series of phosphopeptide cations in a Fourier transform mass spectrometer. The objective of the experiments was to determine whether 266 nm UV irradiation on the phosphopeptide cations would induce unique peptide backbone dissociation. In addition, the general behavior of the phosphate loss (-80 or -98 Da) was monitored, particularly for those phosphopeptides with a phosphotyrosine residue that itself is a UV chromophore. For phosphopeptides with a UV chromophore, their photodissociation behavior was very similar to that of low-energy sustained off-resonance irradiation collisionally activated dissociation (SORI-CAD), with a few exceptions. For example, b- and y-type peptide backbone fragments were prevalent, and their dephosphorylation behavior was consistent with that of the SORI-CAD results. For phosphoserine peptides, the loss of a phosphate group was always observed. On the other hand, for phosphotyrosine peptides, the phosphate loss was found to be dependent on the presence of a basic amino group in the sequence and the charge state of the precursor ions, in agreement with the CAD results in the literature. However, hydrogen atom loss or aromatic side chain loss, which is known to be the excited state specific fragmentation pathway, was rarely observed in our 266 nm UV PD experiments, in contrast to the previous UV PD literature (particularly at 220 nm). The mechanism for these observations is described in terms of dominant internal conversion followed by intramolecular vibrational energy redistribution (IVR).
Collapse
Affiliation(s)
- Soojin Park
- Department of Chemistry and Interdisciplinary Program of Integrated Biotechnology, Sogang University, Seoul 121-742, Republic of Korea
| | | | | | | | | | | |
Collapse
|
16
|
Ly T, Julian R. Ultraviolet Photodissociation: Developments towards Applications for Mass-Spectrometry-Based Proteomics. Angew Chem Int Ed Engl 2009; 48:7130-7. [DOI: 10.1002/anie.200900613] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
17
|
Ly T, Julian R. Photodissoziation durch UV-Licht: Anwendungen in der massenspektrometrischen Proteomforschung. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200900613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|