1
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Ding Y, Bi Q, Huang D, Liao J, Yang L, Luo X, Yang P, Li Y, Yao C, Wei W, Zhang J, Li J, Huang Y, Guo DA. A novel integrated automatic strategy for amino acid composition analysis of seeds from 67 species. Food Chem 2023; 426:136670. [PMID: 37354578 DOI: 10.1016/j.foodchem.2023.136670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 06/06/2023] [Accepted: 06/17/2023] [Indexed: 06/26/2023]
Abstract
The composition and quantity of amino acids (AAs) in seeds are complicated due to the various origins and modifications of different species. In this study, a novel automatic neutral loss filtering (ANLF) strategy based on accurate mass searching by Python was developed to analyze the free and hydrolyzed AA-phenyl isothiocyanate (PITC) derivatives from seeds of Gymnosperm and Angiosperm phyla. Compared with traditional strategies, ANLF showed much higher accuracy in screening AA derivatives by filtering nitrogen-containing non-AA compounds and efficiency in processing large datasets. Meanwhile, the content phenotype of 20 proteinogenic AAs from seeds of these two families was characterized by a 35-min HPLC method combined with an automated peak-matching strategy. AA profiles of 232 batches of seeds from 67 species, consisting of 19 proteinogenic AAs, 21 modified AAs, and 77 unknown AAs, would be a good reference for their application in food and medicine.
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Affiliation(s)
- Yelin Ding
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China; Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Qirui Bi
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Dongdong Huang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jingmei Liao
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China; Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Lin Yang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China; Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xiaoxiao Luo
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Peilei Yang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yun Li
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Changliang Yao
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Wenlong Wei
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jianqing Zhang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jiayuan Li
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yong Huang
- Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - De-An Guo
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China; Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Research Center for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
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2
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Moyer TB, Parsley NC, Sadecki PW, Schug WJ, Hicks LM. Leveraging orthogonal mass spectrometry based strategies for comprehensive sequencing and characterization of ribosomal antimicrobial peptide natural products. Nat Prod Rep 2021; 38:489-509. [PMID: 32929442 PMCID: PMC7956910 DOI: 10.1039/d0np00046a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Covering: Up to July 2020Ribosomal antimicrobial peptide (AMP) natural products, also known as ribosomally synthesized and post-translationally modified peptides (RiPPs) or host defense peptides, demonstrate potent bioactivities and impressive complexity that complicate molecular and biological characterization. Tandem mass spectrometry (MS) has rapidly accelerated bioactive peptide sequencing efforts, yet standard workflows insufficiently address intrinsic AMP diversity. Herein, orthogonal approaches to accelerate comprehensive and accurate molecular characterization without the need for prior isolation are reviewed. Chemical derivatization, proteolysis (enzymatic and chemical cleavage), multistage MS fragmentation, and separation (liquid chromatography and ion mobility) strategies can provide complementary amino acid composition and post-translational modification data to constrain sequence solutions. Examination of two complex case studies, gomesin and styelin D, highlights the practical implementation of the proposed approaches. Finally, we emphasize the importance of heterogeneous AMP peptidoforms that confer varying biological function, an area that warrants significant further development.
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Affiliation(s)
- Tessa B Moyer
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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3
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Steckel A, Borbély A, Uray K, Schlosser G. Quantification of the Effect of Citrulline and Homocitrulline Residues on the Collision-Induced Fragmentation of Peptides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:1744-1750. [PMID: 32559094 PMCID: PMC7590983 DOI: 10.1021/jasms.0c00210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Posttranslational modifications of proteins like citrullination and carbamylation are associated with several diseases. Detailed analytical characterization of citrullinated and carbamylated proteins or peptides could be difficult due to the low concentration of the analytes in complex biological samples. High structural similarity and chemical behavior of citrullinated and carbamylated residues also pose a challenge. We previously reported the "citrulline effect" phenomenon that is manifested in the generation of intense y type ions originating from Cit-Zzz amide bond scissions in collision-induced dissociation tandem mass spectra of citrullinated tryptic peptides. In this study, we created a rigorous tryptic-like model system of both citrulline and homocitrulline-containing peptides that included appropriate and well-defined controls and fragment analogues to quantify the citrulline effect and investigate whether there is an effect for homocitrulline residues as well. Our results show that citrulline residues significantly increased fragmentation at their C-terminus relatively independent of the identity of the following amino acid. In comparison, homocitrulline residues displayed inconclusive results at the same energies. However, the strength of effects was dependent on collision energy and the position of citrulline and homocitrulline in the sequences. As newer software algorithms tend to observe structure-intensity relationships during annotation, this finding increases reliable identification of modified proteins/peptides.
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Affiliation(s)
- Arnold Steckel
- Hevesy György PhD School of Chemistry,
ELTE Eötvös Loránd University, Budapest
1117, Hungary
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest
1117, Hungary
| | - Adina Borbély
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest
1117, Hungary
- Department of Analytical Chemistry, ELTE
Eötvös Loránd University, Budapest 1117,
Hungary
| | - Katalin Uray
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest
1117, Hungary
| | - Gitta Schlosser
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest
1117, Hungary
- Department of Analytical Chemistry, ELTE
Eötvös Loránd University, Budapest 1117,
Hungary
- Phone: +36-1-372 2500/1415.
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4
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Nicolardi S, Kilgour DPA, Dolezal N, Drijfhout JW, Wuhrer M, van der Burgt YEM. Evaluation of Sibling and Twin Fragment Ions Improves the Structural Characterization of Proteins by Top-Down MALDI In-Source Decay Mass Spectrometry. Anal Chem 2020; 92:5871-5881. [PMID: 32212639 PMCID: PMC7178258 DOI: 10.1021/acs.analchem.9b05683] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
![]()
Comprehensive determination
of primary sequence and identification
of post-translational modifications (PTMs) are key elements in protein
structural analysis. Various mass spectrometry (MS) based fragmentation
techniques are powerful approaches for mapping both the amino acid
sequence and PTMs; one of these techniques is matrix-assisted laser
desorption/ionization (MALDI), combined with in-source decay (ISD)
fragmentation and Fourier-transform ion cyclotron resonance (FT-ICR)
MS. MALDI-ISD MS protein analysis involves only minimal sample preparation
and does not require spectral deconvolution. The resulting MALDI-ISD
MS data is complementary to electrospray ionization-based MS/MS sequencing
readouts, providing knowledge on the types of fragment ions is available.
In this study, we evaluate the isotopic distributions of z′ ions in protein top-down MALDI-ISD FT-ICR mass spectra and
show why these distributions can deviate from theoretical profiles
as a result of co-occurring and isomeric z and y-NH3 ions. Two synthetic peptides, containing
either normal or deuterated alanine residues, were used to confirm
the presence and unravel the identity of isomeric z and y-NH3 fragment ions (“twins”).
Furthermore, two reducing MALDI matrices, namely 1,5-diaminonaphthalene
and N-phenyl-p-phenylenediamine
were applied that yield ISD mass spectra with different fragment ion
distributions. This study demonstrates that the relative abundance
of isomeric z and y-NH3 ions requires consideration for accurate and confident assignments
of z′ ions in MALDI-ISD FT-ICR mass spectra.
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Affiliation(s)
- Simone Nicolardi
- Center for Proteomics & Metabolomics, Leiden University Medical Center, Leiden 2333, ZA, The Netherlands
| | - David P A Kilgour
- Department of Chemistry, Nottingham Trent University, Nottingham NG11 0JN, United Kingdom
| | - Natasja Dolezal
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden 2333, ZA, The Netherlands
| | - Jan W Drijfhout
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden 2333, ZA, The Netherlands
| | - Manfred Wuhrer
- Center for Proteomics & Metabolomics, Leiden University Medical Center, Leiden 2333, ZA, The Netherlands
| | - Yuri E M van der Burgt
- Center for Proteomics & Metabolomics, Leiden University Medical Center, Leiden 2333, ZA, The Netherlands
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5
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Steckel A, Uray K, Kalló G, Csosz É, Schlosser G. Investigation of Neutral Losses and the Citrulline Effect for Modified H4 N-Terminal Pentapeptides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:565-573. [PMID: 31967473 PMCID: PMC7309534 DOI: 10.1021/jasms.9b00036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 01/18/2020] [Accepted: 01/21/2020] [Indexed: 05/15/2023]
Abstract
Tandem mass spectrometry is an indispensable tool in proteomics used for protein sequencing and quantitation. On the basis of the sequential fragments usually generated from peptide ions via collision-induced dissociation, electron-transfer dissociation, or a combination of the two, probabilistic database search engines could be used for the identification of the peptides. The correct localization of posttranslational modifications (PTMs) poses a more challenging problem than the general identification of proteins. Histones are involved in the regulation of DNA transcription via the wealth of PTMs on their N-terminal tail. In this study, we analyzed the histone H4 peptide SGRGK incorporating four different posttranslational modifications: citrullination, acetylation, phosphorylation, and arginine methylation at various positions. The pentapeptides model the enzymatic cleavage of the N-terminal tail of human histone H4 protein by LysC protease. Fragmentation of the peptides was investigated using higher-energy collisional dissociation (HCD), electron-transfer dissociation (ETD), and electron-transfer higher-energy collisional dissociation (EThcD) on an ultrahigh resolution and mass accuracy instrument. We found that while all three techniques have their unique characteristics, advantages, and pitfalls, EThcD generated the most fragment ion-rich spectra. Despite potential ambiguities regarding exact fragment identities, full sequence coverage and PTM mapping may also be achievable. We also found novel neutral losses from the charge-reduced precursors characteristic to citrullination in ETD and EThcD which may be used in proteomic applications. N-Terminal acetylation and arginine methylation could also be confirmed by their characteristic neutral losses from the charge-reduced precursors.
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Affiliation(s)
- Arnold Steckel
- Hevesy György PhD School of Chemistry,
ELTE Eötvös Loránd University, Budapest,
Pázmány Péter sétány 1/A, 1117,
Hungary
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest,
Pázmány Péter sétány 1/A, 1117,
Hungary
| | - Katalin Uray
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest,
Pázmány Péter sétány 1/A, 1117,
Hungary
| | - Gergo Kalló
- Proteomics Core Facility, Department of Biochemistry and
Molecular Biology, Faculty of Medicine, University of Debrecen,
Debrecen, Nagyerdei krt. 98, 4032, Hungary
| | - Éva Csosz
- Proteomics Core Facility, Department of Biochemistry and
Molecular Biology, Faculty of Medicine, University of Debrecen,
Debrecen, Nagyerdei krt. 98, 4032, Hungary
| | - Gitta Schlosser
- MTA-ELTE Research Group of Peptide Chemistry,
ELTE Eötvös Loránd University, Budapest,
Pázmány Péter sétány 1/A, 1117,
Hungary
- Department of Analytical Chemistry, ELTE
Eötvös Loránd University, Budapest,
Pázmány Péter sétány 1/A, 1117,
Hungary
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6
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Szczerbiński J, Metternich JB, Goubert G, Zenobi R. How Peptides Dissociate in Plasmonic Hot Spots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1905197. [PMID: 31894644 DOI: 10.1002/smll.201905197] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 11/01/2019] [Indexed: 06/10/2023]
Abstract
Plasmon-induced hot carriers enable dissociation of strong chemical bonds by visible light. This unusual chemistry has been demonstrated for several diatomic and small organic molecules. Here, the scope of plasmon-driven photochemistry is extended to biomolecules and the reactivity of proteins and peptides in plasmonic hot spots is described. Tip-enhanced Raman spectroscopy (TERS) is used to both drive the reactions and to monitor their products. Peptide backbone bonds are found to dissociate in the hot spot, which is reflected in the disappearance of the amide I band in the TER spectra. The observed fragmentation pathway involves nonthermal activation, presumably by dissociative capture of a plasmon-induced hot electron. This fragmentation pathway is known from electron transfer dissociation (ETD) of peptides in gas-phase mass spectrometry (MS), which suggests a general similarity between plasmon-induced photochemistry and nonergodic reactions triggered by electron capture. This analogy may serve as a design principle for plasmon-induced reactions of biomolecules.
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Affiliation(s)
- Jacek Szczerbiński
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Jonas B Metternich
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Guillaume Goubert
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, Laboratory of Organic Chemistry, ETH Zurich, 8093, Zurich, Switzerland
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7
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Kempkes LJM, Martens J, Berden G, Oomens J. w-Type ions formed by electron transfer dissociation of Cys-containing peptides investigated by infrared ion spectroscopy. JOURNAL OF MASS SPECTROMETRY : JMS 2018; 53:1207-1213. [PMID: 30281881 PMCID: PMC6283004 DOI: 10.1002/jms.4298] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 08/24/2018] [Accepted: 09/26/2018] [Indexed: 06/08/2023]
Abstract
In mass spectrometry-based peptide sequencing, electron transfer dissociation (ETD) and electron capture dissociation (ECD) have become well-established fragmentation methods complementary to collision-induced dissociation. The dominant fragmentation pathways during ETD and ECD primarily involve the formation of c- and z• -type ions by cleavage of the peptide backbone at the N─Cα bond, although neutral losses from amino acid side chains have also been observed. Residue-specific neutral side chain losses provide useful information when conducting database searching and de novo sequencing. Here, we use a combination of infrared ion spectroscopy and quantum-chemical calculations to assign the structures of two ETD-generated w-type fragment ions. These ions are spontaneously formed from ETD-generated z• -type fragments by neutral loss of 33 Da in peptides containing a cysteine residue. Analysis of the infrared ion spectra confirms that these z• -ions expel a thiol radical (SH• ) and that a vinyl C═C group is formed at the cleavage site. z• -type fragments containing a Cys residue but not at the cleavage site do not spontaneously expel a thiol radical, but only upon additional collisional activation after ETD.
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Affiliation(s)
- Lisanne J. M. Kempkes
- Radboud University, Institute for Molecules and Materials, FELIX LaboratoryNijmegenThe Netherlands
| | - Jonathan Martens
- Radboud University, Institute for Molecules and Materials, FELIX LaboratoryNijmegenThe Netherlands
| | - Giel Berden
- Radboud University, Institute for Molecules and Materials, FELIX LaboratoryNijmegenThe Netherlands
| | - Jos Oomens
- Radboud University, Institute for Molecules and Materials, FELIX LaboratoryNijmegenThe Netherlands
- Van't Hoff Institute for Molecular SciencesUniversity of AmsterdamAmsterdamThe Netherlands
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8
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Egorov D, Bari S, Boll R, Dörner S, Deinert S, Techert S, Hoekstra R, Zamudio-Bayer V, Lindblad R, Bülow C, Timm M, von Issendorff B, Lau JT, Schlathölter T. Near-Edge Soft X-ray Absorption Mass Spectrometry of Protonated Melittin. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:2138-2151. [PMID: 30047073 DOI: 10.1007/s13361-018-2035-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/10/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
We have investigated the photoionization and photofragmentation yields of gas-phase multiply protonated melittin cations for photon energies at the K-shell absorption edges of carbon, nitrogen, and oxygen. Two similar experimental approaches were employed. In both experiments, mass selected [melittin+qH]q+ (q=2-4) ions were accumulated in radiofrequency ion traps. The trap content was exposed to intense beams of monochromatic soft X-ray photons from synchrotron beamlines and photoproducts were analyzed by means of time-of-flight mass spectrometry. Mass spectra were recorded for fixed photon energies, and partial ion yield spectra were recorded as a function of photon energy. The combination of mass spectrometry and soft X-ray spectroscopy allows for a direct correlation of protein electronic structure with various photoionization channels. Non-dissociative single and double ionization are used as a reference. The contribution of both channels to various backbone scission channels is quantified and related to activation energies and protonation sites. Soft X-ray absorption mass spectrometry combines fast energy deposition with single and double ionization and could complement established activation techniques. Graphical Abstract ᅟ.
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Affiliation(s)
- Dmitrii Egorov
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747AG, Groningen, Netherlands
| | - Sadia Bari
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Rebecca Boll
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Simon Dörner
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Sascha Deinert
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Simone Techert
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
- Institute of X-ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077, Göttingen, Germany
| | - Ronnie Hoekstra
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747AG, Groningen, Netherlands
| | - Vicente Zamudio-Bayer
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, 79104, Freiburg, Germany
| | - Rebecka Lindblad
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Synkrotronljusfysik, Lunds Universitet, 22100, Lund, Sweden
| | - Christine Bülow
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, 10623, Berlin, Germany
| | - Martin Timm
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, 10623, Berlin, Germany
| | - Bernd von Issendorff
- Physikalisches Institut, Universität Freiburg, Hermann-Herder-Str. 3, 79104, Freiburg, Germany
| | - J Tobias Lau
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
- Abteilung für Hochempfindliche Röntgenspektroskopie, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, 12489, Berlin, Germany
| | - Thomas Schlathölter
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747AG, Groningen, Netherlands.
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9
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Affiliation(s)
- Nicholas
M. Riley
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Genome
Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Joshua J. Coon
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Genome
Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department
of Biomolecular Chemistry, University of
Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Morgridge
Institute for Research, Madison, Wisconsin 53715, United States
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10
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Li P, Jackson GP. Charge Transfer Dissociation (CTD) Mass Spectrometry of Peptide Cations: Study of Charge State Effects and Side-Chain Losses. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1271-1281. [PMID: 28091811 DOI: 10.1007/s13361-016-1574-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 12/03/2016] [Accepted: 12/04/2016] [Indexed: 05/04/2023]
Abstract
1+, 2+, and 3+ precursors of substance P and bradykinin were subjected to helium cation irradiation in a 3D ion trap mass spectrometer. Charge exchange with the helium cations produces a variety of fragment ions, the number and type of which are dependent on the charge state of the precursor ions. For 1+ peptide precursors, fragmentation is generally restricted to C-CO backbone bonds (a and x ions), whereas for 2+ and 3+ peptide precursors, all three backbone bonds (C-CO, C-N, and N-Cα) are cleaved. The type of backbone bond cleavage is indicative of possible dissociation channels involved in CTD process, including high-energy, kinetic-based, and ETD-like pathways. In addition to backbone cleavages, amino acid side-chain cleavages are observed in CTD, which are consistent with other high-energy and radical-mediated techniques. The unique dissociation pattern and supplementary information available from side-chain cleavages make CTD a potentially useful activation method for the structural study of gas-phase biomolecules. Graphical Abstract ᅟ.
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Affiliation(s)
- Pengfei Li
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, 26506, USA
| | - Glen P Jackson
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, 26506, USA.
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, WV, 26506-6121, USA.
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11
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Wong YLE, Chen X, Wu R, Hung YLW, Yeung HS, Chan TWD. Generation and Characterization of Gas-Phase Doubly Charged Biradical Peptide Ions (M2+••). Anal Chem 2017; 89:7773-7780. [DOI: 10.1021/acs.analchem.7b01808] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Y. L. Elaine Wong
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Xiangfeng Chen
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
- Key
Laboratory for Applied Technology of Sophisticated Analytical Instruments,
Shandong Analysis and Test Centre, Shandong Academy of Sciences, Jinan, Shandong, People’s Republic of China
| | - Ri Wu
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Y. L. Winnie Hung
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
| | - Hoi Sze Yeung
- Bruker Scientific
Instruments Hong Kong Co. Limited, Kowloon Bay, Hong Kong SAR
| | - T.-W. Dominic Chan
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR
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12
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Commodore JJ, Cassady CJ. Effects of acidic peptide size and sequence on trivalent praseodymium adduction and electron transfer dissociation mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2017; 52:218-229. [PMID: 28170125 PMCID: PMC5407459 DOI: 10.1002/jms.3919] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/31/2017] [Accepted: 02/02/2017] [Indexed: 05/05/2023]
Abstract
Using the lanthanide ion praseodymium, Pr(III), metallated ion formation and electron transfer dissociation (ETD) were studied for 25 biological and model acidic peptides. For chain lengths of seven or more residues, even highly acidic peptides that can be difficult to protonate by electrospray ionization will metallate and undergo abundant ETD fragmentation. Peptides composed of predominantly acidic residues form only the deprotonated ion, [M + Pr - H]2+ ; this ion yields near complete ETD sequence coverage for larger peptides. Peptides with a mixture of acidic and neutral residues generate [M + Pr]3+ , which cleaves between every residue for many peptides. Acidic peptides that contain at least one residue with a basic side chain also produce the protonated ion, [M + Pr + H]4+ ; this ion undergoes the most extensive sequence coverage by ETD. Primarily metallated and non-metallated c- and z-ions form for all peptides investigated. Metal adducted product ions are only present when at least half of the peptide sequence can be incorporated into the ion; this suggests that the metal ion simultaneously attaches to more than one acidic site. The only site consistently lacking dissociation is at the N-terminal side of a proline residue. Increasing peptide chain length generates more backbone cleavage for metal-peptide complexes with the same charge state. For acidic peptides with the same length, increasing the precursor ion charge state from 2+ to 3+ also leads to more cleavage. The results of this study indicate that highly acidic peptides can be sequenced by ETD of complexes formed with Pr(III). Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
| | - Carolyn J. Cassady
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
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13
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Commodore JJ, Cassady CJ. The Effects of Trivalent Lanthanide Cationization on the Electron Transfer Dissociation of Acidic Fibrinopeptide B and its Analogs. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:1499-509. [PMID: 27294379 PMCID: PMC4974135 DOI: 10.1007/s13361-016-1428-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 05/22/2016] [Accepted: 05/23/2016] [Indexed: 05/08/2023]
Abstract
Electrospray ionization (ESI) on mixtures of acidic fibrinopeptide B and two peptide analogs with trivalent lanthanide salts generates [M + Met + H](4+), [M + Met](3+), and [M + Met -H](2+), where M = peptide and Met = metal (except radioactive promethium). These ions undergo extensive and highly efficient electron transfer dissociation (ETD) to form metallated and non-metallated c- and z-ions. All metal adducted product ions contain at least two acidic sites, which suggest attachment of the lanthanide cation at the side chains of one or more acidic residues. The three peptides undergo similar fragmentation. ETD on [M + Met + H](4+) leads to cleavage at every residue; the presence of both a metal ion and an extra proton is very effective in promoting sequence-informative fragmentation. Backbone dissociation of [M + Met](3+) is also extensive, although cleavage does not always occur between adjacent glutamic acid residues. For [M + Met - H ](2+), a more limited range of product ions form. All lanthanide metal peptide complexes display similar fragmentation except for europium (Eu). ETD on [M + Eu - H](2+) and [M + Eu](3+) yields a limited amount of peptide backbone cleavage; however, [M + Eu + H](4+) dissociates extensively with cleavage at every residue. With the exception of the results for Eu(III), metallated peptide ion formation by ESI, ETD fragmentation efficiencies, and product ion formation are unaffected by the identity of the lanthanide cation. Adduction with trivalent lanthanide metal ions is a promising tool for sequence analysis of acidic peptides by ETD. Graphical Abstract ᅟ.
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Affiliation(s)
| | - Carolyn J Cassady
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL, 35487, USA.
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14
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Nair D, Vanuopadath M, Nair BG, Pai JG, Nair SS. Identification and characterization of a library of surfactins and fengycins from a marine endophytic Bacillus sp. J Basic Microbiol 2016; 56:1159-1172. [PMID: 27160506 DOI: 10.1002/jobm.201600029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/24/2016] [Indexed: 11/05/2022]
Abstract
An endophytic bacterial strain from a marine green alga, Ulva lactuca, was isolated and identified by 16S rRNA gene sequencing method. The bacterial isolate was found to secrete two major families of cyclic depsilipopeptides, surfactins, and fengycins. Sequencing of the isolated lipopeptides was carried out using the MSn data obtained from an electrospray ionization (ESI) ion trap mass spectrometer coupled to an HPLC system. The assigned sequences were confirmed by a chemical derivatization approach involving esterification followed by mass spectrometric analysis. Distinction of leucine residues from isoleucine was established through a combined electron transfer dissociation-collision-induced dissociation (ETD-CID) method. The fengycins described in this study were found to cause significant delay of growth of two plants, Vigna radiata (mung bean) and Oryza sativa (rice). To the best of our knowledge, this is the first study describing identification and characterization of cyclic peptides from an endophytic Bacillus sp. isolated from marine algae.
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Affiliation(s)
- Divya Nair
- Amrita School of Biotechnology, Amrita Vishwa Vidyapeetham, Clappana P.O. Kollam, Kerala, India
| | | | - Bipin G Nair
- Amrita School of Biotechnology, Amrita Vishwa Vidyapeetham, Clappana P.O. Kollam, Kerala, India
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15
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McMillen CL, Wright PM, Cassady CJ. Negative Ion In-Source Decay Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry for Sequencing Acidic Peptides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:847-855. [PMID: 26864792 DOI: 10.1007/s13361-016-1345-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 01/15/2016] [Accepted: 01/16/2016] [Indexed: 06/05/2023]
Abstract
Matrix-assisted laser desorption/ionization (MALDI) in-source decay was studied in the negative ion mode on deprotonated peptides to determine its usefulness for obtaining extensive sequence information for acidic peptides. Eight biological acidic peptides, ranging in size from 11 to 33 residues, were studied by negative ion mode ISD (nISD). The matrices 2,5-dihydroxybenzoic acid, 2-aminobenzoic acid, 2-aminobenzamide, 1,5-diaminonaphthalene, 5-amino-1-naphthol, 3-aminoquinoline, and 9-aminoacridine were used with each peptide. Optimal fragmentation was produced with 1,5-diaminonphthalene (DAN), and extensive sequence informative fragmentation was observed for every peptide except hirudin(54-65). Cleavage at the N-Cα bond of the peptide backbone, producing c' and z' ions, was dominant for all peptides. Cleavage of the N-Cα bond N-terminal to proline residues was not observed. The formation of c and z ions is also found in electron transfer dissociation (ETD), electron capture dissociation (ECD), and positive ion mode ISD, which are considered to be radical-driven techniques. Oxidized insulin chain A, which has four highly acidic oxidized cysteine residues, had less extensive fragmentation. This peptide also exhibited the only charged localized fragmentation, with more pronounced product ion formation adjacent to the highly acidic residues. In addition, spectra were obtained by positive ion mode ISD for each protonated peptide; more sequence informative fragmentation was observed via nISD for all peptides. Three of the peptides studied had no product ion formation in ISD, but extensive sequence informative fragmentation was found in their nISD spectra. The results of this study indicate that nISD can be used to readily obtain sequence information for acidic peptides.
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Affiliation(s)
- Chelsea L McMillen
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL, 35487, USA
| | - Patience M Wright
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL, 35487, USA
- Department of Chemistry, The University of Georgia, Athens, GA, 30602, USA
| | - Carolyn J Cassady
- Department of Chemistry, The University of Alabama, Tuscaloosa, AL, 35487, USA.
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16
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Ji Y, Bachschmid MM, Costello CE, Lin C. S- to N-Palmitoyl Transfer During Proteomic Sample Preparation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:677-85. [PMID: 26729453 PMCID: PMC4794353 DOI: 10.1007/s13361-015-1319-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 11/30/2015] [Accepted: 12/01/2015] [Indexed: 05/06/2023]
Abstract
N-palmitoylation has been reported in a number of proteins and suggested to play an important role in protein localization and functions. However, it remains unclear whether N-palmitoylation is a direct enzyme-catalyzed process, or results from intramolecular S- to N-palmitoyl transfer. Here, using the S-palmitoyl peptide standard, GCpalmLGNAK, as the model system, we observed palmitoyl migration from the cysteine residue to either the peptide N-terminus or the lysine side chain during incubation in both neutral and slightly basic buffers commonly used in proteomic sample preparation. Palmitoyl transfer can take place either intra- or inter-molecularly, with the peptide N-terminus being the preferred migration site, presumably because of its lower basicity. The extent of intramolecular palmitoyl migration was low in the system studied, as it required the formation of an entropically unfavored macrocycle intermediate. Intermolecular palmitoyl transfer, however, remained a tangible problem, and may lead to erroneous reporting of in vivo N-palmitoylation. It was found that addition of the MS-compatible detergent RapiGest could significantly inhibit intermolecular palmitoyl transfer, as well as thioester hydrolysis and DTT-induced thioester cleavage. Finally, palmitoyl transfer from the cysteine residue to the peptide N-terminus can also occur in the gas phase, during collision-induced dissociation, and result in false identification of N-palmitoylation. Therefore, one must be careful with both sample preparation and interpretation of tandem mass spectra in the study of N-palmitoylation. Graphical Abstract ᅟ.
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Affiliation(s)
- Yuhuan Ji
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA, 02118, USA
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Markus M Bachschmid
- Cardiovascular Proteomics Center and Vascular Biology Section, Department of Medicine, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Catherine E Costello
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA, 02118, USA
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Cheng Lin
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA, 02118, USA.
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, 02118, USA.
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17
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Rose CM, Rush MJP, Riley NM, Merrill AE, Kwiecien NW, Holden DD, Mullen C, Westphall MS, Coon JJ. A calibration routine for efficient ETD in large-scale proteomics. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:1848-57. [PMID: 26111518 PMCID: PMC5642106 DOI: 10.1007/s13361-015-1183-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/21/2015] [Accepted: 04/22/2015] [Indexed: 05/11/2023]
Abstract
Electron transfer dissociation (ETD) has been broadly adopted and is now available on a variety of commercial mass spectrometers. Unlike collisional activation techniques, optimal performance of ETD requires considerable user knowledge and input. ETD reaction duration is one key parameter that can greatly influence spectral quality and overall experiment outcome. We describe a calibration routine that determines the correct number of reagent anions necessary to reach a defined ETD reaction rate. Implementation of this automated calibration routine on two hybrid Orbitrap platforms illustrate considerable advantages, namely, increased product ion yield with concomitant reduction in scan rates netting up to 75% more unique peptide identifications in a shotgun experiment. Graphical Abstract ᅟ.
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Affiliation(s)
- Christopher M Rose
- Department of Chemistry, University of Wisconsin, Madison, WI, 53706, USA
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA
| | - Matthew J P Rush
- Department of Chemistry, University of Wisconsin, Madison, WI, 53706, USA
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA
| | - Nicholas M Riley
- Department of Chemistry, University of Wisconsin, Madison, WI, 53706, USA
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA
| | - Anna E Merrill
- Department of Chemistry, University of Wisconsin, Madison, WI, 53706, USA
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA
| | - Nicholas W Kwiecien
- Department of Chemistry, University of Wisconsin, Madison, WI, 53706, USA
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA
| | | | | | - Michael S Westphall
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA
| | - Joshua J Coon
- Department of Chemistry, University of Wisconsin, Madison, WI, 53706, USA.
- Department of Biomolecular Chemistry, University of Wisconsin, Madison, WI, 53706, USA.
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI, 53706, USA.
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18
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Hunt DF, Shabanowitz J, Bai DL. Peptide Sequence Analysis by Electron Transfer Dissociation Mass Spectrometry: A Web-Based Tutorial. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:1256-8. [PMID: 25821049 PMCID: PMC4475668 DOI: 10.1007/s13361-015-1105-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 02/09/2015] [Accepted: 02/16/2015] [Indexed: 05/28/2023]
Abstract
We created a web-based tutorial designed to teach manual interpretation and identification of spectra acquired using electron transfer dissociation (ETD). The tutorial provides an explanation of the ETD fragmentation process with the goal of identifying all of the significant peaks in a spectrum. We discuss determination of the precursor mass and charge state, neutral losses, electron transfer without dissociation (ETnoD), and the mechanisms by which fragment ions are created. Our hope is to provide a tool that presents the information already taught in D.F.H.'s short courses in a way that is easy for any student or researcher in the mass spectrometry community to access. The tutorial may be found at http://www.huntlab.org.
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Affiliation(s)
- Donald F. Hunt
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
- Department of Pathology, University of Virginia, Charlottesville, VA, USA
| | | | - Dina L. Bai
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
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19
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Kelstrup CD, Frese C, Heck AJR, Olsen JV, Nielsen ML. Analytical utility of mass spectral binning in proteomic experiments by SPectral Immonium Ion Detection (SPIID). Mol Cell Proteomics 2014; 13:1914-24. [PMID: 24895383 PMCID: PMC4125726 DOI: 10.1074/mcp.o113.035915] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Unambiguous identification of tandem mass spectra is a cornerstone in mass-spectrometry-based proteomics. As the study of post-translational modifications (PTMs) by means of shotgun proteomics progresses in depth and coverage, the ability to correctly identify PTM-bearing peptides is essential, increasing the demand for advanced data interpretation. Several PTMs are known to generate unique fragment ions during tandem mass spectrometry, the so-called diagnostic ions, which unequivocally identify a given mass spectrum as related to a specific PTM. Although such ions offer tremendous analytical advantages, algorithms to decipher MS/MS spectra for the presence of diagnostic ions in an unbiased manner are currently lacking. Here, we present a systematic spectral-pattern-based approach for the discovery of diagnostic ions and new fragmentation mechanisms in shotgun proteomics datasets. The developed software tool is designed to analyze large sets of high-resolution peptide fragmentation spectra independent of the fragmentation method, instrument type, or protease employed. To benchmark the software tool, we analyzed large higher-energy collisional activation dissociation datasets of samples containing phosphorylation, ubiquitylation, SUMOylation, formylation, and lysine acetylation. Using the developed software tool, we were able to identify known diagnostic ions by comparing histograms of modified and unmodified peptide spectra. Because the investigated tandem mass spectra data were acquired with high mass accuracy, unambiguous interpretation and determination of the chemical composition for the majority of detected fragment ions was feasible. Collectively we present a freely available software tool that allows for comprehensive and automatic analysis of analogous product ions in tandem mass spectra and systematic mapping of fragmentation mechanisms related to common amino acids.
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Affiliation(s)
- Christian D Kelstrup
- From the ‡Department of Proteomics, The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Faculty of Health Sciences, DK-2200 Copenhagen, Denmark
| | - Christian Frese
- §Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584CH Utrecht, The Netherlands
| | - Albert J R Heck
- §Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584CH Utrecht, The Netherlands
| | - Jesper V Olsen
- From the ‡Department of Proteomics, The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Faculty of Health Sciences, DK-2200 Copenhagen, Denmark
| | - Michael L Nielsen
- From the ‡Department of Proteomics, The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Faculty of Health Sciences, DK-2200 Copenhagen, Denmark;
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20
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Pepin R, Laszlo KJ, Peng B, Marek A, Bush MF, Tureček F. Comprehensive Analysis of Gly-Leu-Gly-Gly-Lys Peptide Dication Structures and Cation-Radical Dissociations Following Electron Transfer: From Electron Attachment to Backbone Cleavage, Ion–Molecule Complexes, and Fragment Separation. J Phys Chem A 2013; 118:308-24. [DOI: 10.1021/jp411100c] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Robert Pepin
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
| | - Kenneth J. Laszlo
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
| | - Bo Peng
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
| | - Aleš Marek
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
| | - Matthew F. Bush
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
| | - František Tureček
- Department of Chemistry, Bagley Hall, Box 351700, University of Washington, Seattle, Washington 98195-1700, United States
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21
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Affiliation(s)
- František Tureček
- Department of Chemistry, Bagley Hall, University of Washington , Seattle, Washington 98195-1700, United States
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22
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Liu J, McLuckey SA. Electron Transfer Dissociation: Effects of Cation Charge State on Product Partitioning in Ion/Ion Electron Transfer to Multiply Protonated Polypeptides. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2012; 330-332:174-181. [PMID: 23264749 PMCID: PMC3525064 DOI: 10.1016/j.ijms.2012.07.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The effect of cation charge state on product partitioning in the gas-phase ion/ion electron transfer reactions of multiply protonated tryptic peptides, model peptides, and relatively large peptides with singly charged radical anions has been examined. In particular, partitioning into various competing channels, such as proton transfer (PT) versus electron transfer (ET), electron transfer with subsequent dissociation (ETD) versus electron transfer with no dissociation (ET,noD), and fragmentation of backbone bonds versus fragmentation of side chains, was measured quantitatively as a function of peptide charge state to allow insights to be drawn about the fundamental aspects of ion/ion reactions that lead to ETD. The ET channel increases relative to the PT channel, ETD increases relative to ET,noD, and fragmentation at backbone bonds increases relative to side-chain cleavages as cation charge state increases. The increase in ET versus PT with charge state is consistent with a Landau-Zener based curve-crossing model. An optimum charge state for ET is predicted by the model for the ground state-to-ground state reaction. However, when the population of excited product ion states is considered, it is possible that a decrease in ET efficiency as charge state increases will not be observed due to the possibility of the population of excited electronic states of the products. Several factors can contribute to the increase in ETD versus ET,noD and backbone cleavage versus side-chain losses. These factors include an increase in reaction exothermicity and charge state dependent differences in precursor and product ion structures, stabilities, and sites of protonation.
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Affiliation(s)
| | - Scott A. McLuckey
- Address reprint requests to: Dr. S.A. McLuckey, 560 Oval Drive, Department of Chemistry, Purdue University, West Lafayette, IN, USA 47907-2084, Phone: (765) 494-5270, Fax: (765) 494-0239,
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23
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Niedermeyer THJ, Strohalm M. mMass as a software tool for the annotation of cyclic peptide tandem mass spectra. PLoS One 2012; 7:e44913. [PMID: 23028676 PMCID: PMC3441486 DOI: 10.1371/journal.pone.0044913] [Citation(s) in RCA: 210] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 08/09/2012] [Indexed: 11/19/2022] Open
Abstract
Natural or synthetic cyclic peptides often possess pronounced bioactivity. Their mass spectrometric characterization is difficult due to the predominant occurrence of non-proteinogenic monomers and the complex fragmentation patterns observed. Even though several software tools for cyclic peptide tandem mass spectra annotation have been published, these tools are still unable to annotate a majority of the signals observed in experimentally obtained mass spectra. They are thus not suitable for extensive mass spectrometric characterization of these compounds. This lack of advanced and user-friendly software tools has motivated us to extend the fragmentation module of a freely available open-source software, mMass (http://www.mmass.org), to allow for cyclic peptide tandem mass spectra annotation and interpretation. The resulting software has been tested on several cyanobacterial and other naturally occurring peptides. It has been found to be superior to other currently available tools concerning both usability and annotation extensiveness. Thus it is highly useful for accelerating the structure confirmation and elucidation of cyclic as well as linear peptides and depsipeptides.
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24
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Li W, Wysocki VH. ETD fragmentation features improve algorithm. Expert Rev Proteomics 2012; 9:241-3. [PMID: 22809203 DOI: 10.1586/epr.12.23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Electron transfer dissociation (ETD) is an alternative technique used in mass spectrometry-based proteomics experiments. Because it is newer, most of the protein identification algorithms for ETD are still a simple derivation of well-established collision-activated dissociation algorithms without the consideration of many unique ETD spectral features. Sridhara and coworkers recently reported removing the charge-reduced precursors and corresponding neutral loss peaks to improve ETD peptide identification with the Open Mass Spectrometry Search Algorithm (OMSSA). These peaks were also used to deduce the charge of the precursors for low resolution data. The scheme is a concrete example of implementing known ETD fragmentation features to improve a protein identification algorithm.
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Affiliation(s)
- Wenzhou Li
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, USA
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25
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Hansen TA, Kryuchkov F, Kjeldsen F. Reduction in Database Search Space by Utilization of Amino Acid Composition Information from Electron Transfer Dissociation and Higher-Energy Collisional Dissociation Mass Spectra. Anal Chem 2012; 84:6638-45. [DOI: 10.1021/ac3010007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Thomas A. Hansen
- Department
of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Fedor Kryuchkov
- Department
of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Frank Kjeldsen
- Department
of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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26
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Lu Y, Zhou X, Stemmer PM, Reid GE. Sulfonium ion derivatization, isobaric stable isotope labeling and data dependent CID- and ETD-MS/MS for enhanced phosphopeptide quantitation, identification and phosphorylation site characterization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:577-93. [PMID: 21952753 PMCID: PMC4228788 DOI: 10.1007/s13361-011-0190-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 06/03/2011] [Accepted: 06/03/2011] [Indexed: 05/12/2023]
Abstract
An amine specific peptide derivatization strategy involving the use of novel isobaric stable isotope encoded 'fixed charge' sulfonium ion reagents, coupled with an analysis strategy employing capillary HPLC, ESI-MS, and automated data dependent ion trap CID-MS/MS, -MS(3), and/or ETD-MS/MS, has been developed for the improved quantitative analysis of protein phosphorylation, and for identification and characterization of their site(s) of modification. Derivatization of 50 synthetic phosphopeptides with S,S'-dimethylthiobutanoylhydroxysuccinimide ester iodide (DMBNHS), followed by analysis using capillary HPLC-ESI-MS, yielded an average 2.5-fold increase in ionization efficiencies and a significant increase in the presence and/or abundance of higher charge state precursor ions compared to the non-derivatized phosphopeptides. Notably, 44% of the phosphopeptides (22 of 50) in their underivatized states yielded precursor ions whose maximum charge states corresponded to +2, while only 8% (4 of 50) remained at this maximum charge state following DMBNHS derivatization. Quantitative analysis was achieved by measuring the abundances of the diagnostic product ions corresponding to the neutral losses of 'light' (S(CH(3))(2)) and 'heavy' (S(CD(3))(2)) dimethylsulfide exclusively formed upon CID-MS/MS of isobaric stable isotope labeled forms of the DMBNHS derivatized phosphopeptides. Under these conditions, the phosphate group stayed intact. Access for a greater number of peptides to provide enhanced phosphopeptide sequence identification and phosphorylation site characterization was achieved via automated data-dependent CID-MS(3) or ETD-MS/MS analysis due to the formation of the higher charge state precursor ions. Importantly, improved sequence coverage was observed using ETD-MS/MS following introduction of the sulfonium ion fixed charge, but with no detrimental effects on ETD fragmentation efficiency.
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Affiliation(s)
- Yali Lu
- Department of Chemistry, Michigan State University, 229 Chemistry Building, Michigan State University, East Lansing, MI, 48824, USA
| | - Xiao Zhou
- Department of Chemistry, Michigan State University, 229 Chemistry Building, Michigan State University, East Lansing, MI, 48824, USA
| | - Paul M. Stemmer
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
| | - Gavin E. Reid
- Department of Chemistry, Michigan State University, 229 Chemistry Building, Michigan State University, East Lansing, MI, 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
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27
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Rumachik NG, McAlister GC, Russell JD, Bailey DJ, Wenger CD, Coon JJ. Characterizing peptide neutral losses induced by negative electron-transfer dissociation (NETD). JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:718-27. [PMID: 22290482 PMCID: PMC3371390 DOI: 10.1007/s13361-011-0331-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 12/23/2011] [Accepted: 12/25/2011] [Indexed: 05/10/2023]
Abstract
We implemented negative electron-transfer dissociation (NETD) on a hybrid ion trap/Orbitrap mass spectrometer to conduct ion/ion reactions using peptide anions and radical reagent cations. In addition to sequence-informative ladders of a•- and x-type fragment ions, NETD generated intense neutral loss peaks corresponding to the entire or partial side-chain cleavage from amino acids constituting a given peptide. Thus, a critical step towards the characterization of this recently introduced fragmentation technique is a systematic study of synthetic peptides to identify common neutral losses and preferential fragmentation pathways. Examining 46 synthetic peptides with high mass accuracy and high resolution analysis permitted facile determination of the chemical composition of each neutral loss. We identified 19 unique neutral losses from 14 amino acids and three modified amino acids, and assessed the specificity and sensitivity of each neutral loss using a database of 1542 confidently identified peptides generated from NETD shotgun experiments employing high-pH separations and negative electrospray ionization. As residue-specific neutral losses indicate the presence of certain amino acids, we determined that many neutral losses have potential diagnostic utility. We envision this catalogue of neutral losses being incorporated into database search algorithms to improve peptide identification specificity and to further advance characterization of the acidic proteome.
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Affiliation(s)
- Neil G. Rumachik
- Departments of Chemistry, University of Wisconsin, Madison, WI 53706, USA
| | | | - Jason D. Russell
- Departments of Chemistry, University of Wisconsin, Madison, WI 53706, USA
| | - Derek J. Bailey
- Departments of Chemistry, University of Wisconsin, Madison, WI 53706, USA
| | - Craig D. Wenger
- Departments of Chemistry, University of Wisconsin, Madison, WI 53706, USA
| | - Joshua J. Coon
- Departments of Chemistry, University of Wisconsin, Madison, WI 53706, USA
- Biomolecular Chemistry, University of Wisconsin, Madison, WI 53706, USA
- Genome Center of Wisconsin, University of Wisconsin, Madison, WI 53706, USA
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28
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Tobe BT, Hou J, Crain AM, Singec I, Snyder EY, Brill LM. Phosphoproteomic analysis: an emerging role in deciphering cellular signaling in human embryonic stem cells and their differentiated derivatives. Stem Cell Rev Rep 2012; 8:16-31. [PMID: 22009073 PMCID: PMC3839940 DOI: 10.1007/s12015-011-9317-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cellular signaling is largely controlled by protein phosphorylation. This post-translational modification (PTM) has been extensively analyzed when examining one or a few protein phosphorylation events that effect cell signaling. However, protein kinase-driven signaling networks, comprising total (phospho)proteomes, largely control cell fate. Therefore, large-scale analysis of differentially regulated protein phosphorylation is central to elucidating complex cellular events, including maintenance of pluripotency and differentiation of embryonic stem cells (ESCs). The current technology of choice for total phosphoproteome and combined total proteome plus total phosphoproteome (termed (phospho)proteome) analyses is multidimensional liquid chromatography-(MDLC) tandem mass spectrometry (MS/MS). Advances in the use of MDLC for separation of peptides comprising total (phospho)proteomes, phosphopeptide enrichment, separation of enriched fractions, and quantitative peptide identification by MS/MS have been rapid in recent years, as have improvements in the sensitivity, speed, and accuracy of mass spectrometers. Increasingly deep coverage of (phospho)proteomes is allowing an improved understanding of changes in protein phosphorylation networks as cells respond to stimuli and progress from one undifferentiated or differentiated state to another. Although MDLC-MS/MS studies are powerful, understanding the interpretation of the data is important, and targeted experimental pursuit of biological predictions provided by total (phospho)proteome analyses is needed. (Phospho)proteomic analyses of pluripotent stem cells are in their infancy at this time. However, such studies have already begun to contribute to an improved and accelerated understanding of basic pluripotent stem cell signaling and fate control, especially at the systems-biology level.
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Affiliation(s)
- Brian T.D. Tobe
- The Sanford-Burnham Medical Research Institute, La Jolla, California, USA
| | - Junjie Hou
- The Sanford-Burnham Medical Research Institute, La Jolla, California, USA
| | - Andrew M. Crain
- The Sanford-Burnham Medical Research Institute, La Jolla, California, USA
| | - Ilyas Singec
- The Sanford-Burnham Medical Research Institute, La Jolla, California, USA
| | - Evan Y. Snyder
- The Sanford-Burnham Medical Research Institute, La Jolla, California, USA
| | - Laurence M. Brill
- The Sanford-Burnham Medical Research Institute, La Jolla, California, USA
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29
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Kim MS, Pandey A. Electron transfer dissociation mass spectrometry in proteomics. Proteomics 2012; 12:530-42. [PMID: 22246976 DOI: 10.1002/pmic.201100517] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 10/25/2011] [Accepted: 11/02/2011] [Indexed: 01/30/2023]
Abstract
Mass spectrometry has rapidly evolved to become the platform of choice for proteomic analysis. While CID remains the major fragmentation method for peptide sequencing, electron transfer dissociation (ETD) is emerging as a complementary method for the characterization of peptides and post-translational modifications (PTMs). Here, we review the evolution of ETD and some of its newer applications including characterization of PTMs, non-tryptic peptides and intact proteins. We will also discuss some of the unique features of ETD such as its complementarity with CID and the use of alternating CID/ETD along with issues pertaining to analysis of ETD data. The potential of ETD for applications such as multiple reaction monitoring and proteogenomics in the future will also be discussed.
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Affiliation(s)
- Min-Sik Kim
- Department of Biological Chemistry, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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30
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Niedermeyer THJ, Strohalm M. mMass as a software tool for the annotation of cyclic peptide tandem mass spectra. PLoS One 2012. [PMID: 23028676 DOI: 10.1055/s-0032-1321299] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Natural or synthetic cyclic peptides often possess pronounced bioactivity. Their mass spectrometric characterization is difficult due to the predominant occurrence of non-proteinogenic monomers and the complex fragmentation patterns observed. Even though several software tools for cyclic peptide tandem mass spectra annotation have been published, these tools are still unable to annotate a majority of the signals observed in experimentally obtained mass spectra. They are thus not suitable for extensive mass spectrometric characterization of these compounds. This lack of advanced and user-friendly software tools has motivated us to extend the fragmentation module of a freely available open-source software, mMass (http://www.mmass.org), to allow for cyclic peptide tandem mass spectra annotation and interpretation. The resulting software has been tested on several cyanobacterial and other naturally occurring peptides. It has been found to be superior to other currently available tools concerning both usability and annotation extensiveness. Thus it is highly useful for accelerating the structure confirmation and elucidation of cyclic as well as linear peptides and depsipeptides.
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31
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Gupta K, Kumar M, Chandrashekara K, Krishnan KS, Balaram P. Combined electron transfer dissociation-collision-induced dissociation fragmentation in the mass spectrometric distinction of leucine, isoleucine, and hydroxyproline residues in Peptide natural products. J Proteome Res 2011; 11:515-22. [PMID: 22111579 DOI: 10.1021/pr200091v] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Distinctions between isobaric residues have been a major challenge in mass spectrometric peptide sequencing. Here, we propose a methodology for distinction among isobaric leucine, isoleucine, and hydroxyproline, a commonly found post-translationally modified amino acid with a nominal mass of 113 Da, through a combined electron transfer dissociation-collision-induced dissociation approach. While the absence of c and z(•) ions, corresponding to the Yyy-Xxx (Xxx = Leu, Ile, or Hyp) segment, is indicative of the presence of hydroxyproline, loss of isopropyl (Δm = 43 Da) or ethyl radicals (Δm = 29 Da), through collisional activation of z radical ions, are characteristic of leucine or isoleucine, respectively. Radical migration processes permit distinctions even in cases where the specific z(•) ions, corresponding to the Yyy-Leu or -Ile segments, are absent or of low intensity. This tandem mass spectrometric (MS(n)) method has been successfully implemented in a liquid chromatography-MS(n) platform to determine the identity of 23 different isobaric residues from a mixture of five different peptides. The approach is convenient for distinction of isobaric residues from any crude peptide mixture, typically encountered in natural peptide libraries or proteomic analysis.
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Affiliation(s)
- Kallol Gupta
- Molecular Biophysics Unit, Indian Institute of Science , Bangalore 560012, India
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32
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Li W, Song C, Bailey DJ, Tseng GC, Coon JJ, Wysocki VH. Statistical analysis of electron transfer dissociation pairwise fragmentation patterns. Anal Chem 2011; 83:9540-5. [PMID: 22022956 DOI: 10.1021/ac202327r] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Electron transfer dissociation (ETD) is an alternative peptide dissociation method developed in recent years. Compared with the traditional collision induced dissociation (CID) b and y ion formation, ETD generates c and z ions and the backbone cleavage is believed to be less selective. We have reported previously the application of a statistical data mining strategy, K-means clustering, to discover fragmentation patterns for CID, and here we report application of this approach to ETD spectra. We use ETD data sets from digestions with three different proteases. Data analysis shows that selective cleavages do exist for ETD, with the fragmentation patterns affected by protease, charge states, and amino acid residue compositions. It is also noticed that the c(n-1) ion, corresponding to loss of the C-terminal amino acid residue, is statistically strong regardless of the residue at the C-terminus of the peptide, which suggests that the peptide gas phase conformation plays an important role in the dissociation pathways. These patterns provide a basis for mechanism elucidation, spectral prediction, and improvement of ETD peptide identification algorithms.
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Affiliation(s)
- Wenzhou Li
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
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Jensen CS, Wyer JA, Houmøller J, Hvelplund P, Nielsen SB. Electron-capture induced dissociation of doubly charged dipeptides: on the neutral losses and N–Cα bond cleavages. Phys Chem Chem Phys 2011; 13:18373-8. [DOI: 10.1039/c1cp21549c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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