1
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Lu H, Zhu Z, Fields L, Zhang H, Li L. Mass Spectrometry Structural Proteomics Enabled by Limited Proteolysis and Cross-Linking. MASS SPECTROMETRY REVIEWS 2024. [PMID: 39300771 DOI: 10.1002/mas.21908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 08/31/2024] [Accepted: 09/02/2024] [Indexed: 09/22/2024]
Abstract
The exploration of protein structure and function stands at the forefront of life science and represents an ever-expanding focus in the development of proteomics. As mass spectrometry (MS) offers readout of protein conformational changes at both the protein and peptide levels, MS-based structural proteomics is making significant strides in the realms of structural and molecular biology, complementing traditional structural biology techniques. This review focuses on two powerful MS-based techniques for peptide-level readout, namely limited proteolysis-mass spectrometry (LiP-MS) and cross-linking mass spectrometry (XL-MS). First, we discuss the principles, features, and different workflows of these two methods. Subsequently, we delve into the bioinformatics strategies and software tools used for interpreting data associated with these protein conformation readouts and how the data can be integrated with other computational tools. Furthermore, we provide a comprehensive summary of the noteworthy applications of LiP-MS and XL-MS in diverse areas including neurodegenerative diseases, interactome studies, membrane proteins, and artificial intelligence-based structural analysis. Finally, we discuss the factors that modulate protein conformational changes. We also highlight the remaining challenges in understanding the intricacies of protein conformational changes by LiP-MS and XL-MS technologies.
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Affiliation(s)
- Haiyan Lu
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Zexin Zhu
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Lauren Fields
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Hua Zhang
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Lingjun Li
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Lachman Institute for Pharmaceutical Development, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
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2
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Polák M, Černý J, Novák P. Isotopic Depletion Increases the Spatial Resolution of FPOP Top-Down Mass Spectrometry Analysis. Anal Chem 2024; 96:1478-1487. [PMID: 38226459 PMCID: PMC10831798 DOI: 10.1021/acs.analchem.3c03759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/08/2023] [Accepted: 12/15/2023] [Indexed: 01/17/2024]
Abstract
Protein radical labeling, like fast photochemical oxidation of proteins (FPOP), coupled to a top-down mass spectrometry (MS) analysis offers an alternative analytical method for probing protein structure or protein interaction with other biomolecules, for instance, proteins and DNA. However, with the increasing mass of studied analytes, the MS/MS spectra become complex and exhibit a low signal-to-noise ratio. Nevertheless, these difficulties may be overcome by protein isotope depletion. Thus, we aimed to use protein isotope depletion to analyze FPOP-oxidized samples by top-down MS analysis. For this purpose, we prepared isotopically natural (IN) and depleted (ID) forms of the FOXO4 DNA binding domain (FOXO4-DBD) and studied the protein-DNA interaction interface with double-stranded DNA, the insulin response element (IRE), after exposing the complex to hydroxyl radicals. As shown by comparing tandem mass spectra of natural and depleted proteins, the ID form increased the signal-to-noise ratio of useful fragment ions, thereby enhancing the sequence coverage by more than 19%. This improvement in the detection of fragment ions enabled us to detect 22 more oxidized residues in the ID samples than in the IN sample. Moreover, less common modifications were detected in the ID sample, including the formation of ketones and lysine carbonylation. Given the higher quality of ID top-down MSMS data set, these results provide more detailed information on the complex formation between transcription factors and DNA-response elements. Therefore, our study highlights the benefits of isotopic depletion for quantitative top-down proteomics. Data are available via ProteomeXchange with the identifier PXD044447.
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Affiliation(s)
- Marek Polák
- Institute
of Microbiology of the Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles
University, 12843 Prague, Czech Republic
| | - Jiří Černý
- Laboratory
of Structural Bioinformatics of Proteins, Institute of Biotechnology of the Czech Academy of Sciences, 14220 Prague, Czech Republic
| | - Petr Novák
- Institute
of Microbiology of the Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles
University, 12843 Prague, Czech Republic
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3
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Kenderdine T, Fabris D. The multifaceted roles of mass spectrometric analysis in nucleic acids drug discovery and development. MASS SPECTROMETRY REVIEWS 2023; 42:1332-1357. [PMID: 34939674 PMCID: PMC9218015 DOI: 10.1002/mas.21766] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/23/2021] [Accepted: 11/22/2021] [Indexed: 06/07/2023]
Abstract
The deceptively simple concepts of mass determination and fragment analysis are the basis for the application of mass spectrometry (MS) to a boundless range of analytes, including fundamental components and polymeric forms of nucleic acids (NAs). This platform affords the intrinsic ability to observe first-hand the effects of NA-active drugs on the chemical structure, composition, and conformation of their targets, which might affect their ability to interact with cognate NAs, proteins, and other biomolecules present in a natural environment. The possibility of interfacing with high-performance separation techniques represents a multiplying factor that extends these capabilities to cover complex sample mixtures obtained from organisms that were exposed to NA-active drugs. This report provides a brief overview of these capabilities in the context of the analysis of the products of NA-drug activity and NA therapeutics. The selected examples offer proof-of-principle of the applicability of this platform to all phases of the journey undertaken by any successful NA drug from laboratory to bedside, and provide the rationale for its rapid expansion outside traditional laboratory settings in support to ever growing manufacturing operations.
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Affiliation(s)
| | - Dan Fabris
- Department of Chemistry, University of Connecticut
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4
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Palasser M, Breuker K. RNA Chemical Labeling with Site-Specific, Relative Quantification by Mass Spectrometry for the Structural Study of a Neomycin-Sensing Riboswitch Aptamer Domain. Chempluschem 2022; 87:e202200256. [PMID: 36220343 PMCID: PMC9828840 DOI: 10.1002/cplu.202200256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/14/2022] [Indexed: 01/12/2023]
Abstract
High-resolution mass spectrometry was used for the label-free, direct localization and relative quantification of CMC+ -modifications of a neomycin-sensing riboswitch aptamer domain in the absence and presence of the aminoglycoside ligands neomycin B, ribostamycin, and paromomycin. The chemical probing and MS data for the free riboswitch show high exposure to solvent of the uridine nucleobases U7, U8, U13, U14, U18 as part of the proposed internal and apical loops, but those of U10 and U21 as part of the proposed internal loop were found to be far less exposed than expected. Thus, our data are in better agreement with the proposed secondary structure of the riboswitch in complexes with aminoglycosides than with that of free RNA. For the riboswitch in complexes with neomycin B, ribostamycin, and paromomycin, we found highly similar CMC+ -modification patterns and excellent agreement with previous NMR studies. Differences between the chemical probing and MS data in the absence and presence of the aminoglycoside ligands were quantitative rather than qualitative (i. e., the same nucleobases were labeled, but to different extents) and can be rationalized by stabilization of both the proposed bulge and the apical loop by aminoglycoside binding. Our study shows that chemical probing and mass spectrometry can provide important structural information and complement other techniques such as NMR spectroscopy.
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Affiliation(s)
- Michael Palasser
- Institut of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Kathrin Breuker
- Institut of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
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5
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Barozzi C, Zacchini F, Asghar S, Montanaro L. Ribosomal RNA Pseudouridylation: Will Newly Available Methods Finally Define the Contribution of This Modification to Human Ribosome Plasticity? Front Genet 2022; 13:920987. [PMID: 35719370 PMCID: PMC9198423 DOI: 10.3389/fgene.2022.920987] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 05/09/2022] [Indexed: 12/05/2022] Open
Abstract
In human rRNA, at least 104 specific uridine residues are modified to pseudouridine. Many of these pseudouridylation sites are located within functionally important ribosomal domains and can influence ribosomal functional features. Until recently, available methods failed to reliably quantify the level of modification at each specific rRNA site. Therefore, information obtained so far only partially explained the degree of regulation of pseudouridylation in different physiological and pathological conditions. In this focused review, we provide a summary of the methods that are now available for the study of rRNA pseudouridylation, discussing the perspectives that newly developed approaches are offering.
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Affiliation(s)
- Chiara Barozzi
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale (DIMES), Alma Mater Studiorum—Università di Bologna, Bologna, Italy
- Centro di Ricerca Biomedica Applicata, CRBA, Universita di Bologna, Policlinico di Sant’Orsola, Bologna, Italy
| | - Federico Zacchini
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale (DIMES), Alma Mater Studiorum—Università di Bologna, Bologna, Italy
- Centro di Ricerca Biomedica Applicata, CRBA, Universita di Bologna, Policlinico di Sant’Orsola, Bologna, Italy
| | - Sidra Asghar
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale (DIMES), Alma Mater Studiorum—Università di Bologna, Bologna, Italy
- Centro di Ricerca Biomedica Applicata, CRBA, Universita di Bologna, Policlinico di Sant’Orsola, Bologna, Italy
| | - Lorenzo Montanaro
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale (DIMES), Alma Mater Studiorum—Università di Bologna, Bologna, Italy
- Centro di Ricerca Biomedica Applicata, CRBA, Universita di Bologna, Policlinico di Sant’Orsola, Bologna, Italy
- Departmental Program in Laboratory Medicine, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
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6
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Polák M, Yassaghi G, Kavan D, Filandr F, Fiala J, Kukačka Z, Halada P, Loginov DS, Novák P. Utilization of Fast Photochemical Oxidation of Proteins and Both Bottom-up and Top-down Mass Spectrometry for Structural Characterization of a Transcription Factor-dsDNA Complex. Anal Chem 2022; 94:3203-3210. [PMID: 35134296 DOI: 10.1021/acs.analchem.1c04746] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A combination of covalent labeling techniques and mass spectrometry (MS) is currently a progressive approach for deriving insights related to the mapping of protein surfaces or protein-ligand interactions. In this study, we mapped an interaction interface between the DNA binding domain (DBD) of FOXO4 protein and the DNA binding element (DAF16) using fast photochemical oxidation of proteins (FPOP). Residues involved in protein-DNA interaction were identified using the bottom-up approach. To confirm the findings and avoid a misinterpretation of the obtained data, caused by possible multiple radical oxidations leading to the protein surface alteration and oxidation of deeply buried amino acid residues, a top-down approach was employed for the first time in FPOP analysis. An isolation of singly oxidized ions enabled their gas-phase separation from multiply oxidized species followed by CID and ECD fragmentation. Application of both fragmentation techniques allowed generation of complementary fragment sets, out of which the regions shielded in the presence of DNA were deduced. The findings obtained by bottom-up and top-down approaches were highly consistent. Finally, FPOP results were compared with those of the HDX study of the FOXO4-DBD·DAF16 complex. No contradictions were found between the methods. Moreover, their combination provides complementary information related to the structure and dynamics of the protein-DNA complex. Data are available via ProteomeXchange with identifier PXD027624.
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Affiliation(s)
- Marek Polák
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic.,Faculty of Science, Charles University, Prague, 12843, Czech Republic
| | - Ghazaleh Yassaghi
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic
| | - Daniel Kavan
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic.,Faculty of Science, Charles University, Prague, 12843, Czech Republic
| | - František Filandr
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic.,Faculty of Science, Charles University, Prague, 12843, Czech Republic
| | - Jan Fiala
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic.,Faculty of Science, Charles University, Prague, 12843, Czech Republic
| | - Zdeněk Kukačka
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic
| | - Petr Halada
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic
| | - Dmitry S Loginov
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic.,Orekhovich Institute of Biomedical Chemistry, Moscow, 119191, Russia
| | - Petr Novák
- Institute of Microbiology, The Czech Academy of Sciences, Prague, 14220, Czech Republic
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7
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Largy E, König A, Ghosh A, Ghosh D, Benabou S, Rosu F, Gabelica V. Mass Spectrometry of Nucleic Acid Noncovalent Complexes. Chem Rev 2021; 122:7720-7839. [PMID: 34587741 DOI: 10.1021/acs.chemrev.1c00386] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nucleic acids have been among the first targets for antitumor drugs and antibiotics. With the unveiling of new biological roles in regulation of gene expression, specific DNA and RNA structures have become very attractive targets, especially when the corresponding proteins are undruggable. Biophysical assays to assess target structure as well as ligand binding stoichiometry, affinity, specificity, and binding modes are part of the drug development process. Mass spectrometry offers unique advantages as a biophysical method owing to its ability to distinguish each stoichiometry present in a mixture. In addition, advanced mass spectrometry approaches (reactive probing, fragmentation techniques, ion mobility spectrometry, ion spectroscopy) provide more detailed information on the complexes. Here, we review the fundamentals of mass spectrometry and all its particularities when studying noncovalent nucleic acid structures, and then review what has been learned thanks to mass spectrometry on nucleic acid structures, self-assemblies (e.g., duplexes or G-quadruplexes), and their complexes with ligands.
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Affiliation(s)
- Eric Largy
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Alexander König
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Anirban Ghosh
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Debasmita Ghosh
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Sanae Benabou
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
| | - Frédéric Rosu
- Univ. Bordeaux, CNRS, INSERM, IECB, UMS 3033, F-33600 Pessac, France
| | - Valérie Gabelica
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, IECB, F-33600 Pessac, France
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8
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Sutton JM, Kim J, El Zahar NM, Bartlett MG. BIOANALYSIS AND BIOTRANSFORMATION OF OLIGONUCLEOTIDE THERAPEUTICS BY LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2021; 40:334-358. [PMID: 32588492 DOI: 10.1002/mas.21641] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 05/05/2020] [Accepted: 05/28/2020] [Indexed: 06/11/2023]
Abstract
Since 2016, eight new oligonucleotide therapies have been approved which has led to increased interest in oligonucleotide analysis. There is a particular need for powerful bioanalytical tools to study the metabolism and biotransformation of these molecules. This review provides the background on the biological basis of these molecules as currently used in therapies. The article also reviews the current state of analytical methodology including state of the art sample preparation techniques, liquid chromatography-mass spectrometry methods, and the current limits of detection/quantitation. Finally, the article summarizes the challenges in oligonucleotide bioanalysis and provides future perspectives for this emerging field. © 2020 John Wiley & Sons Ltd.
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Affiliation(s)
- James Michael Sutton
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
| | - Jaeah Kim
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
| | - Noha M El Zahar
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Organization of African Unity Street, Cairo, 11566, Egypt
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, 250 West Green Street, Athens, GA, 30602-2352
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9
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Kukačka Z, Rosůlek M, Jelínek J, Slavata L, Kavan D, Novák P. LinX: A Software Tool for Uncommon Cross-Linking Chemistry. J Proteome Res 2021; 20:2021-2027. [PMID: 33657806 DOI: 10.1021/acs.jproteome.0c00858] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical cross-linking mass spectrometry has become a popular tool in structural biology. Although several algorithms exist that efficiently analyze data-dependent mass spectrometric data, the algorithm to identify and quantify intermolecular cross-links located at the interaction interface of homodimer molecules was missing. The algorithm in LinX utilizes high mass accuracy for ion identification. In contrast with standard data-dependent analysis, LinX enables the elucidation of cross-linked peptides originating from the interaction interface of homodimers labeled by 14N/15N, including their ratio or cross-links from protein-nucleic acid complexes. The software is written in Java language, and its source code and a detailed user's guide are freely available at https://github.com/KukackaZ/LinX or https://ms-utils.org/LinX. Data are accessible via the ProteomeXchange server with the data set identifier PXD023522.
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Affiliation(s)
- Zdeněk Kukačka
- Institute of Microbiology, v.v.i., The Czech Academy of Sciences, Videnska 1083, Prague 14220, Czech Republic
| | - Michal Rosůlek
- Institute of Microbiology, v.v.i., The Czech Academy of Sciences, Videnska 1083, Prague 14220, Czech Republic.,Department of Biochemistry, Faculty of Science, Charles University, Albertov 6, 12800 Prague 2, Czech Republic
| | - Jan Jelínek
- Institute of Microbiology, v.v.i., The Czech Academy of Sciences, Videnska 1083, Prague 14220, Czech Republic.,Department of Software Engineering, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 12000 Prague 2, Czech Republic
| | - Lukáš Slavata
- Institute of Microbiology, v.v.i., The Czech Academy of Sciences, Videnska 1083, Prague 14220, Czech Republic.,Department of Biochemistry, Faculty of Science, Charles University, Albertov 6, 12800 Prague 2, Czech Republic
| | - Daniel Kavan
- Institute of Microbiology, v.v.i., The Czech Academy of Sciences, Videnska 1083, Prague 14220, Czech Republic.,Department of Biochemistry, Faculty of Science, Charles University, Albertov 6, 12800 Prague 2, Czech Republic
| | - Petr Novák
- Institute of Microbiology, v.v.i., The Czech Academy of Sciences, Videnska 1083, Prague 14220, Czech Republic.,Department of Biochemistry, Faculty of Science, Charles University, Albertov 6, 12800 Prague 2, Czech Republic
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10
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Yoluç Y, Ammann G, Barraud P, Jora M, Limbach PA, Motorin Y, Marchand V, Tisné C, Borland K, Kellner S. Instrumental analysis of RNA modifications. Crit Rev Biochem Mol Biol 2021; 56:178-204. [PMID: 33618598 DOI: 10.1080/10409238.2021.1887807] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Organisms from all domains of life invest a substantial amount of energy for the introduction of RNA modifications into nearly all transcripts studied to date. Instrumental analysis of RNA can focus on the modified residues and reveal the function of these epitranscriptomic marks. Here, we will review recent advances and breakthroughs achieved by NMR spectroscopy, sequencing, and mass spectrometry of the epitranscriptome.
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Affiliation(s)
- Yasemin Yoluç
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Gregor Ammann
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Pierre Barraud
- Expression génétique microbienne, UMR 8261, CNRS, Institut de biologie physico-chimique, IBPC, Université de Paris, Paris, France
| | - Manasses Jora
- Department of Chemistry, University of Cincinnati, Cincinnati, OH, USA
| | - Patrick A Limbach
- Department of Chemistry, University of Cincinnati, Cincinnati, OH, USA
| | - Yuri Motorin
- Université de Lorraine, CNRS, UMR7365 IMoPA, Nancy, France
| | - Virginie Marchand
- Université de Lorraine, CNRS, INSERM, Epitranscriptomics and RNA Sequencing Core facility, UM S2008, IBSLor, Nancy, France
| | - Carine Tisné
- Expression génétique microbienne, UMR 8261, CNRS, Institut de biologie physico-chimique, IBPC, Université de Paris, Paris, France
| | - Kayla Borland
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany
| | - Stefanie Kellner
- Department of Chemistry, Ludwig Maximilians University, Munich, Germany.,Institute of Pharmaceutical Chemistry, Goethe-University, Frankfurt, Germany
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11
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Ortiz D, Gasilova N, Sepulveda F, Patiny L, Dyson PJ, Menin L. Aom 2 S: A new web-based application for DNA/RNA tandem mass spectrometry data interpretation. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8927. [PMID: 32812285 DOI: 10.1002/rcm.8927] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/31/2020] [Accepted: 08/15/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE The Analysis of Oligonucleotide Modifications from Mass Spectra (Aom2 S) was created to support the analysis of oligonucleotide mass spectra. This application complements the existing software tools by providing a comprehensive analysis of oligonucleotide fragments from high-resolution tandem mass spectrometry (HR-MS/MS) data in a flexible and user-friendly manner, directly accessible through a web browser without any need for installation. METHODS MS measurements of aminoC6-DNA and inosine-RNA were performed using an LTQ Orbitrap FT-MS instrument. The obtained data were analyzed by our newly developed open-source package Aom2 S accessible from the ms.epfl.ch web page or directly at https://mstools.epfl.ch/am2s/ to demonstrate the various functionalities of this tool, notably the possibility to identify different product ions from a nucleotide sequence with any fixed/variable modification by matching theoretical isotopic patterns to any experimental mass spectra with similarity scores ranking. RESULTS A detailed description of the Aom2 S tool with its user-friendly interface is exemplified using HR-MS/MS data of modified DNA and RNA oligonucleotides. Explanations of analysis parameters and tool workflow, as well as multiple options for viewing and exporting the results, are provided. Product ion assignment and modification localization can be achieved in seconds, and results can be exported as tables, matched mass spectra, and fragmentation maps. CONCLUSIONS A new open source tool (Aom2 S) for the analysis of HR-MS/MS data for modified DNA and RNA oligonucleotides is described. Aom2 S is fast, highly flexible, and versatile, allowing automatic precursor and product ion assignment in a comprehensive manner, including internal fragments and variable modification localization, with clear graphical representation of the results.
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Affiliation(s)
- Daniel Ortiz
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Natalia Gasilova
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Francisco Sepulveda
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Luc Patiny
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Paul J Dyson
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Laure Menin
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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12
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Calderisi G, Glasner H, Breuker K. Radical Transfer Dissociation for De Novo Characterization of Modified Ribonucleic Acids by Mass Spectrometry. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Giovanni Calderisi
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität Innsbruck Innrain 80/82 6020 Innsbruck Austria
| | - Heidelinde Glasner
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität Innsbruck Innrain 80/82 6020 Innsbruck Austria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität Innsbruck Innrain 80/82 6020 Innsbruck Austria
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13
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Calderisi G, Glasner H, Breuker K. Radical Transfer Dissociation for De Novo Characterization of Modified Ribonucleic Acids by Mass Spectrometry. Angew Chem Int Ed Engl 2020; 59:4309-4313. [PMID: 31867820 PMCID: PMC7065001 DOI: 10.1002/anie.201914275] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Indexed: 12/20/2022]
Abstract
Mass spectrometry (MS) can reliably detect and localize all mass-altering modifications of ribonucleic acids (RNA), but current MS approaches that allow for simultaneous de novo sequencing and modification analysis generally require specialized instrumentation. Here we report a novel RNA dissociation technique, radical transfer dissociation (RTD), that can be used for the comprehensive de novo characterization of ribonucleic acids and their posttranscriptional or synthetic modifications. We demonstrate full sequence coverage for RNA consisting of up to 39 nucleotides and show that RTD is especially useful for RNA with highly labile modifications such as 5-hydroxymethylcytidine and 5-formylcytidine.
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Affiliation(s)
- Giovanni Calderisi
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80/826020InnsbruckAustria
| | - Heidelinde Glasner
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80/826020InnsbruckAustria
| | - Kathrin Breuker
- Institut für Organische Chemie and Center for Molecular Biosciences Innsbruck (CMBI)Universität InnsbruckInnrain 80/826020InnsbruckAustria
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14
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Martin Somer A, Macaluso V, Barnes GL, Yang L, Pratihar S, Song K, Hase WL, Spezia R. Role of Chemical Dynamics Simulations in Mass Spectrometry Studies of Collision-Induced Dissociation and Collisions of Biological Ions with Organic Surfaces. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:2-24. [PMID: 32881516 DOI: 10.1021/jasms.9b00062] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this article, a perspective is given of chemical dynamics simulations of collisions of biological ions with surfaces and of collision-induced dissociation (CID) of ions. The simulations provide an atomic-level understanding of the collisions and, overall, are in quite good agreement with experiment. An integral component of ion/surface collisions is energy transfer to the internal degrees of freedom of both the ion and the surface. The simulations reveal how this energy transfer depends on the collision energy, incident angle, biological ion, and surface. With energy transfer to the ion's vibration fragmentation may occur, i.e. surface-induced dissociation (SID), and the simulations discovered a new fragmentation mechanism, called shattering, for which the ion fragments as it collides with the surface. The simulations also provide insight into the atomistic dynamics of soft-landing and reactive-landing of ions on surfaces. The CID simulations compared activation by multiple "soft" collisions, resulting in random excitation, versus high energy single collisions and nonrandom excitation. These two activation methods may result in different fragment ions. Simulations provide fragmentation products in agreement with experiments and, hence, can provide additional information regarding the reaction mechanisms taking place in experiment. Such studies paved the way on using simulations as an independent and predictive tool in increasing fundamental understanding of CID and related processes.
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Affiliation(s)
- Ana Martin Somer
- Departamento de Química, Facultad de Ciencias, Módulo 13 Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC Cantoblanco, 28049 Madrid, Spain
| | - Veronica Macaluso
- LAMBE, Univ Evry, CNRS, CEA, Université Paris-Saclay, 91025 Evry, France
| | - George L Barnes
- Department of Chemistry and Biochemistry, Siena College, Loudonville, New York 12211, United States
| | - Li Yang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P.R. China
| | - Subha Pratihar
- Department of Chemistry and Biochemistry Texas Tech University, Lubbock, Texas 79409, United States
| | - Kihyung Song
- Department of Chemistry, Korea National University of Education, Chungbuk 28644, Republic of Korea
| | - William L Hase
- Department of Chemistry and Biochemistry Texas Tech University, Lubbock, Texas 79409, United States
| | - Riccardo Spezia
- Sorbonne Université, CNRS, Laboratoire de Chimie Théorique, LCT, 4, Place Jussieu, Paris, 75252 Cedex 05, France
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15
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Ponce-Salvatierra A, Astha, Merdas K, Nithin C, Ghosh P, Mukherjee S, Bujnicki JM. Computational modeling of RNA 3D structure based on experimental data. Biosci Rep 2019; 39:BSR20180430. [PMID: 30670629 PMCID: PMC6367127 DOI: 10.1042/bsr20180430] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 01/02/2023] Open
Abstract
RNA molecules are master regulators of cells. They are involved in a variety of molecular processes: they transmit genetic information, sense cellular signals and communicate responses, and even catalyze chemical reactions. As in the case of proteins, RNA function is dictated by its structure and by its ability to adopt different conformations, which in turn is encoded in the sequence. Experimental determination of high-resolution RNA structures is both laborious and difficult, and therefore the majority of known RNAs remain structurally uncharacterized. To address this problem, predictive computational methods were developed based on the accumulated knowledge of RNA structures determined so far, the physical basis of the RNA folding, and taking into account evolutionary considerations, such as conservation of functionally important motifs. However, all theoretical methods suffer from various limitations, and they are generally unable to accurately predict structures for RNA sequences longer than 100-nt residues unless aided by additional experimental data. In this article, we review experimental methods that can generate data usable by computational methods, as well as computational approaches for RNA structure prediction that can utilize data from experimental analyses. We outline methods and data types that can be potentially useful for RNA 3D structure modeling but are not commonly used by the existing software, suggesting directions for future development.
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Affiliation(s)
- Almudena Ponce-Salvatierra
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
| | - Astha
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
| | - Katarzyna Merdas
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
| | - Chandran Nithin
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
| | - Pritha Ghosh
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
| | - Sunandan Mukherjee
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, Warsaw PL-02-109, Poland
- Bioinformatics Laboratory, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, ul. Umultowska 89, Poznan PL-61-614, Poland
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16
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Bifunctional cross-linking approaches for mass spectrometry-based investigation of nucleic acids and protein-nucleic acid assemblies. Methods 2018; 144:64-78. [PMID: 29753003 DOI: 10.1016/j.ymeth.2018.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/30/2018] [Accepted: 05/04/2018] [Indexed: 12/13/2022] Open
Abstract
With the goal of expanding the very limited toolkit of cross-linking agents available for nucleic acids and their protein complexes, we evaluated the merits of a wide range of bifunctional agents that may be capable of reacting with the functional groups characteristic of these types of biopolymers. The survey specifically focused on the ability of test reagents to produce desirable inter-molecular conjugates, which could reveal the identity of interacting components and the position of mutual contacts, while also considering a series of practical criteria for their utilization as viable nucleic acid probes. The survey employed models consisting of DNA, RNA, and corresponding protein complexes to mimic as close as possible typical applications. Denaturing polyacrylamide gel electrophoresis (PAGE) and mass spectrometric (MS) analyses were implemented in concert to monitor the formation of the desired conjugates. In particular, the former was used as a rapid and inexpensive tool for the efficient evaluation of cross-linker activity under a broad range of experimental conditions. The latter was applied after preliminary rounds of reaction optimization to enable full-fledged product characterization and, more significantly, differentiation between mono-functional and intra- versus inter-molecular conjugates. This information provided the feedback necessary to further optimize reaction conditions and explain possible outcomes. Among the reagents tested in the study, platinum complexes and nitrogen mustards manifested the most favorable characteristics for practical cross-linking applications, whereas other compounds provided inferior yields, or produced rather unstable conjugates that did not survive the selected analytical conditions. The observed outcomes will help guide the selection of the most appropriate cross-linking reagent for a specific task, whereas the experimental conditions described here will provide an excellent starting point for approaching these types of applications. As a whole, the results of the survey clearly emphasize that finding a universal reagent, which may afford excellent performance with all types of nucleic acid substrates, will require extending the exploration beyond the traditional chemistries employed to modify the constitutive functional groups of these vital biopolymers.
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17
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Pawlowski JW, Carrick I, Kaltashov IA. Integration of On-Column Chemical Reactions in Protein Characterization by Liquid Chromatography/Mass Spectrometry: Cross-Path Reactive Chromatography. Anal Chem 2018; 90:1348-1355. [DOI: 10.1021/acs.analchem.7b04328] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jake W. Pawlowski
- Department of Chemistry, University of Massachusetts—Amherst, Amherst, Massachusetts 01003, United States
| | - Ian Carrick
- Department of Chemistry, University of Massachusetts—Amherst, Amherst, Massachusetts 01003, United States
| | - Igor A. Kaltashov
- Department of Chemistry, University of Massachusetts—Amherst, Amherst, Massachusetts 01003, United States
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18
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Glasner H, Riml C, Micura R, Breuker K. Label-free, direct localization and relative quantitation of the RNA nucleobase methylations m6A, m5C, m3U, and m5U by top-down mass spectrometry. Nucleic Acids Res 2017; 45:8014-8025. [PMID: 28549193 PMCID: PMC5570050 DOI: 10.1093/nar/gkx470] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/23/2017] [Indexed: 01/28/2023] Open
Abstract
Nucleobase methylations are ubiquitous posttranscriptional modifications of ribonucleic acids (RNA) that can substantially increase the structural diversity of RNA in a highly dynamic fashion with implications for gene expression and human disease. However, high throughput, deep sequencing does not generally provide information on posttranscriptional modifications (PTMs). A promising alternative approach for the characterization of PTMs, i.e. their identification, localization, and relative quantitation, is top-down mass spectrometry (MS). In this study, we have investigated how specific nucleobase methylations affect RNA ionization in electrospray ionization (ESI), and backbone cleavage in collisionally activated dissociation (CAD) and electron detachment dissociation (EDD). For this purpose, we have developed two new approaches for the characterization of RNA methylations in mixtures of either isomers of RNA or nonisomeric RNA forms. Fragment ions from dissociation experiments were analyzed to identify the modification type, to localize the modification sites, and to reveal the site-specific, relative extent of modification for each site.
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Affiliation(s)
- Heidelinde Glasner
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Christian Riml
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
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19
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Schürch S. Characterization of nucleic acids by tandem mass spectrometry - The second decade (2004-2013): From DNA to RNA and modified sequences. MASS SPECTROMETRY REVIEWS 2016; 35:483-523. [PMID: 25288464 DOI: 10.1002/mas.21442] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 05/04/2014] [Accepted: 05/04/2014] [Indexed: 06/03/2023]
Abstract
Nucleic acids play key roles in the storage and processing of genetic information, as well as in the regulation of cellular processes. Consequently, they represent attractive targets for drugs against gene-related diseases. On the other hand, synthetic oligonucleotide analogues have found application as chemotherapeutic agents targeting cellular DNA and RNA. The development of effective nucleic acid-based chemotherapeutic strategies requires adequate analytical techniques capable of providing detailed information about the nucleotide sequences, the presence of structural modifications, the formation of higher-order structures, as well as the interaction of nucleic acids with other cellular components and chemotherapeutic agents. Due to the impressive technical and methodological developments of the past years, tandem mass spectrometry has evolved to one of the most powerful tools supporting research related to nucleic acids. This review covers the literature of the past decade devoted to the tandem mass spectrometric investigation of nucleic acids, with the main focus on the fundamental mechanistic aspects governing the gas-phase dissociation of DNA, RNA, modified oligonucleotide analogues, and their adducts with metal ions. Additionally, recent findings on the elucidation of nucleic acid higher-order structures by tandem mass spectrometry are reviewed. © 2014 Wiley Periodicals, Inc., Mass Spec Rev 35:483-523, 2016.
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Affiliation(s)
- Stefan Schürch
- Department of Chemistry and Biochemistry, University of Bern, CH-3012, Bern, Switzerland
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20
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Protein Structural Analysis via Mass Spectrometry-Based Proteomics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 919:397-431. [PMID: 27975228 DOI: 10.1007/978-3-319-41448-5_19] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Modern mass spectrometry (MS) technologies have provided a versatile platform that can be combined with a large number of techniques to analyze protein structure and dynamics. These techniques include the three detailed in this chapter: (1) hydrogen/deuterium exchange (HDX), (2) limited proteolysis, and (3) chemical crosslinking (CX). HDX relies on the change in mass of a protein upon its dilution into deuterated buffer, which results in varied deuterium content within its backbone amides. Structural information on surface exposed, flexible or disordered linker regions of proteins can be achieved through limited proteolysis, using a variety of proteases and only small extents of digestion. CX refers to the covalent coupling of distinct chemical species and has been used to analyze the structure, function and interactions of proteins by identifying crosslinking sites that are formed by small multi-functional reagents, termed crosslinkers. Each of these MS applications is capable of revealing structural information for proteins when used either with or without other typical high resolution techniques, including NMR and X-ray crystallography.
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21
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Kukacka Z, Rosulek M, Strohalm M, Kavan D, Novak P. Mapping protein structural changes by quantitative cross-linking. Methods 2015; 89:112-20. [DOI: 10.1016/j.ymeth.2015.05.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 04/29/2015] [Accepted: 05/26/2015] [Indexed: 11/24/2022] Open
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22
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Scalabrin M, Siu Y, Asare-Okai PN, Fabris D. Structure-specific ribonucleases for MS-based elucidation of higher-order RNA structure. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:1136-1145. [PMID: 24845355 PMCID: PMC6911265 DOI: 10.1007/s13361-014-0911-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/08/2014] [Accepted: 04/08/2014] [Indexed: 06/03/2023]
Abstract
Supported by high-throughput sequencing technologies, structure-specific nucleases are experiencing a renaissance as biochemical probes for genome-wide mapping of nucleic acid structure. This report explores the benefits and pitfalls of the application of Mung bean (Mb) and V1 nuclease, which attack specifically single- and double-stranded regions of nucleic acids, as possible structural probes to be employed in combination with MS detection. Both enzymes were found capable of operating in ammonium-based solutions that are preferred for high-resolution analysis by direct infusion electrospray ionization (ESI). Sequence analysis by tandem mass spectrometry (MS/MS) was performed to confirm mapping assignments and to resolve possible ambiguities arising from the concomitant formation of isobaric products with identical base composition and different sequences. The observed products grouped together into ladder-type series that facilitated their assignment to unique regions of the substrate, but revealed also a certain level of uncertainty in identifying the boundaries between paired and unpaired regions. Various experimental factors that are known to stabilize nucleic acid structure, such as higher ionic strength, presence of Mg(II), etc., increased the accuracy of cleavage information, but did not completely eliminate deviations from expected results. These observations suggest extreme caution in interpreting the results afforded by these types of reagents. Regardless of the analytical platform of choice, the results highlighted the need to repeat probing experiments under the most diverse possible conditions to recognize potential artifacts and to increase the level of confidence in the observed structural information.
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Affiliation(s)
- Matteo Scalabrin
- The RNA Institute, University at Albany-SUNY, Albany, NY, 12222, USA
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23
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Schermann SM, Simmons DA, Konermann L. Mass spectrometry-based approaches to protein–ligand interactions. Expert Rev Proteomics 2014; 2:475-85. [PMID: 16097882 DOI: 10.1586/14789450.2.4.475] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
One of the greatest current challenges in proteomics is to develop an understanding of cellular communication and regulation processes, most of which involve noncovalent interactions of proteins with various binding partners. Mass spectrometry plays an important role in all aspects of these research efforts. This article provides a survey of mass spectrometry-based approaches for exploring protein-ligand interactions. A wide array of techniques is available, and the choice of method depends on the specific problem at hand. For example, the high-throughput screening of compound libraries for binding to a specific receptor requires different approaches than structural studies on multiprotein complexes. This review is directed to readers wishing to obtain a concise yet comprehensive overview of existing experimental techniques. Specific emphasis is placed on emerging methods that have been developed within the last few years.
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Affiliation(s)
- Sonya M Schermann
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
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24
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Tinnefeld V, Sickmann A, Ahrends R. Catch me if you can: challenges and applications of cross-linking approaches. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2014; 20:99-116. [PMID: 24881459 DOI: 10.1255/ejms.1259] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Biomolecular complexes are the groundwork of life and the basis for cell signaling, energy transfer, motion, stability and cellular metabolism. Understanding the underlying complex interactions on the molecular level is an essential step to obtain a comprehensive insight into cellular and systems biology. For the investigation of molecular interactions, various methods, including Förster resonance energy transfer, nuclear magnetic resonance spectroscopy, X-ray crystallography and yeast two-hybrid screening, can be utilized. Nevertheless, the most reliable approach for structural proteomics and the identification of novel protein-binding partners is chemical cross-linking. The rationale is that upon forming a covalent bond between a protein and its interaction partner (protein, lipid, RNA/DNA, carbohydrate) the native complex state is "frozen" and accessible for detailed mass spectrometric analysis. In this review we provide a synopsis on crosslinker design, chemistry, pitfalls, limitations and novel applications in the field, and feature an overview of current software applications.
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25
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Micura R, Kreutz C, Breuker K. A personal perspective on chemistry-driven RNA research. Biopolymers 2013; 99:1114-23. [PMID: 23754524 PMCID: PMC4477180 DOI: 10.1002/bip.22299] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 05/27/2013] [Indexed: 12/14/2022]
Abstract
In this mini review, we discuss how our understanding of ribonucleic acid (RNA) properties becomes significantly deepened when a broad range of modern chemical and biophysical methods is applied. We span our perspective from RNA solid-phase synthesis and site-specific labeling to single-molecule fluorescence-resonance-energy-transfer imaging and NMR spectroscopy approaches to explore the dynamics of RNA over a broad timescale. We then move on to Fourier-transform-ion-cyclotron-resonance mass spectrometry (FT-ICR-MS) as a powerful technique for RNA sequencing and modification analysis. The novel methodological developments are discussed for selected biological systems that include the thiamine-pyrophosphate riboswitch, HIV and ribosomal A-site RNA, and transfer RNA.
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Affiliation(s)
- Ronald Micura
- Institute of Organic Chemistry, Center for Molecular Biosciences (CMBI), Center for Chemistry and Biomedicine (CCB), University of Innsbruck, Innrain 80-82, Innsbruck, 6020, Austria
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26
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Nyakas A, Blum LC, Stucki SR, Reymond JL, Schürch S. OMA and OPA--software-supported mass spectra analysis of native and modified nucleic acids. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2013; 24:249-256. [PMID: 23264149 DOI: 10.1007/s13361-012-0529-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 10/26/2012] [Accepted: 10/30/2012] [Indexed: 06/01/2023]
Abstract
The platform-independent software package consisting of the oligonucleotide mass assembler (OMA) and the oligonucleotide peak analyzer (OPA) was created to support the analysis of oligonucleotide mass spectra. It calculates all theoretically possible fragments of a given input sequence and annotates it to an experimental spectrum, thus, saving a large amount of manual processing time. The software performs analysis of precursor and product ion spectra of oligonucleotides and their analogues comprising user-defined modifications of the backbone, the nucleobases, or the sugar moiety, as well as adducts with metal ions or drugs. The ability to expand the library of building blocks and to implement individual structural variations makes it extremely useful for supporting the analysis of therapeutically active compounds. The functionality of the software tool is demonstrated on the examples of a platinated double-stranded oligonucleotide and a modified RNA sequence. Experiments also reveal the unique dissociation behavior of platinated higher-order DNA structures.
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Affiliation(s)
- Adrien Nyakas
- Genome BC Proteomics Centre, University of Victoria, Victoria, BC, Canada
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27
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Nei YW, Hallowita N, Steill JD, Oomens J, Rodgers MT. Infrared multiple photon dissociation action spectroscopy of deprotonated DNA mononucleotides: gas-phase conformations and energetics. J Phys Chem A 2013; 117:1319-35. [PMID: 23289585 DOI: 10.1021/jp3077936] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The gas phase structures of the deprotonated 2'-deoxymononucleotides including 2'-deoxyadenosine-5'-monophosphate (dA5'p), 2'-deoxycytidine-5'-monophosphate (dC5'p), 2'-deoxyguanosine-5'-monophosphate (dG5'p), and thymidine-5'-monophosphate (T5'p) are examined via infrared multiple photon dissociation (IRMPD) action spectroscopy and theoretical electronic structure calculations. The measured IRMPD action spectra of all four deprotonated DNA mononucleotides exhibit unique spectral features in the region extending from ~600 to 1800 cm(-1) such that they can be readily differentiated from one another. The measured IRMPD action spectra are compared to the linear IR spectra calculated at the B3LYP/6-311+G(d,p) level of theory to determine the conformations of these species accessed in the experiments. On the basis of these comparisons and the computed energetic information, the most stable conformations of the deprotonated forms of dA5'p, dC5'p, and T5'p are conformers where the ribose moiety adopts a C3' endo conformation and the nucleobase is in an anti conformation. By contrast, the most stable conformations of the deprotonated form of dG5'p are conformers where the ribose adapts a C3' endo conformation and the nucleobase is in a syn conformation. In addition to the ground-state conformers, several stable low-energy excited conformers that differ slightly in the orientation of the phosphate ester moiety were also accessed in the experiments.
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Affiliation(s)
- Y-w Nei
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
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28
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Doria F, Nadai M, Folini M, Scalabrin M, Germani L, Sattin G, Mella M, Palumbo M, Zaffaroni N, Fabris D, Freccero M, Richter SN. Targeting loop adenines in G-quadruplex by a selective oxirane. Chemistry 2012; 19:78-81. [PMID: 23212868 DOI: 10.1002/chem.201203097] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Indexed: 11/06/2022]
Abstract
Caught in the oxirane: Naphthalene diimides conjugated to a quinone methide and an oxirane have been synthesized and investigated as selective DNA G-quadruplex alkylating agents. The oxirane derivative generates a stable adduct with a G-quadruplex and shows selective alkylation of the loop adenines, as illustrated.
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Affiliation(s)
- Filippo Doria
- Dipartimento di Chimica, Università di Pavia, V.le Taramelli 10, 27100 Pavia (Italy)
| | - Matteo Nadai
- Dipartimento di Medicina Molecolare, Università di Padova, via Gabelli 63, 35121 Padua, Italy
| | - Marco Folini
- Dipartimento di Oncologia Sperimentale e Medicina Molecolare, Fondazione IRCCS Istituto Nazionale dei Tumori, Via G. Amadeo 42,20133 Milano, Italy
| | - Matteo Scalabrin
- The RNA Institute of University at Albany (SUNY), Albany, New York
| | - Luca Germani
- Dipartimento di Chimica, Università di Pavia, V.le Taramelli 10, 27100 Pavia (Italy)
| | - Giovanna Sattin
- Dipartimento di Medicina Molecolare, Università di Padova, via Gabelli 63, 35121 Padua, Italy
| | - Mariella Mella
- Dipartimento di Chimica, Università di Pavia, V.le Taramelli 10, 27100 Pavia (Italy)
| | - Manlio Palumbo
- Department of Pharmaceutical and Pharmacological Sciences, Università di Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Nadia Zaffaroni
- Dipartimento di Oncologia Sperimentale e Medicina Molecolare, Fondazione IRCCS Istituto Nazionale dei Tumori, Via G. Amadeo 42,20133 Milano, Italy
| | - Daniele Fabris
- The RNA Institute of University at Albany (SUNY), Albany, New York
| | - Mauro Freccero
- Dipartimento di Chimica, Università di Pavia, V.le Taramelli 10, 27100 Pavia (Italy)
| | - Sara N Richter
- Dipartimento di Medicina Molecolare, Università di Padova, via Gabelli 63, 35121 Padua, Italy
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29
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Taucher M, Ganisl B, Breuker K. Identification, localization, and relative quantitation of pseudouridine in RNA by tandem mass spectrometry of hydrolysis products. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2011; 304:91-97. [PMID: 21960742 PMCID: PMC3180913 DOI: 10.1016/j.ijms.2010.05.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The constitutional isomers uridine (U) and pseudouridine (Ψ) cannot be distinguished from each other by simple mass measurements of RNA or its fragments because the conversion of U into Ψ is a "mass-silent" post-transcriptional modification. Here we propose a new mass spectrometry based method for identification, localization, and relative quantitation of Ψ in RNA consisting of ∼20 nucleotides that does not require chemical labeling. Our approach takes advantage of the different fragmentation behavior of uridine (N-glycosidic bond) and pseudouridine (C-glycosidic bond) residues in RNA upon collisionally activated dissociation.
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Affiliation(s)
| | | | - Kathrin Breuker
- Institute of Organic Chemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
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Parr C, Pierce SE, Smith SI, Brodbelt JS. Investigation of the Reactivity of Oligodeoxynucleotides with Glyoxal and KMnO(4) Chemical Probes by Electrospray Ionization Mass Spectrometry. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2011; 304:115-123. [PMID: 21743793 PMCID: PMC3130548 DOI: 10.1016/j.ijms.2010.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The reactions of two well-known chemical probes, glyoxal and potassium permanganate (KMnO(4)), with oligodeoxynucleotides were monitored by electrospray ionization (ESI) mass spectrometry to evaluate the influence of the sequence of DNA, its secondary structure, and interactions with associated ligands on the reactivity of the two probes. Glyoxal, a guanine-reactive probe, incorporated a mass shift of 58 Da, and potassium permanganate (KMnO(4)) is a thymine-reactive probe that resulted in a mass shift of 34 Da. The reactions depended on the accessibility of the nucleobases, and the peak abundances of the adducts in the ESI-mass spectra were used to quantify the extent of the chemical probe reactions. In this study, both mixed-base sequences were studied as well as control sequences in which one reactive site was located at the terminus or center of the oligodeoxynucleotide while the surrounding bases were a second, different nucleobase. In addition, the reactions of the chemical probes with non-covalent complexes formed between DNA and either actinomycin D or ethidium bromide, both known to interact with single strand DNA, were evaluated.
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Affiliation(s)
- Carol Parr
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712
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31
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Abstract
Alternative approaches complementing the existing technologies for analysis of nucleic acids and their assemblies are necessary to take on the new challenges posed by the postgenomic era. The versatility of MS in biopolymer analysis and its ability to reach beyond sequence information are the basis of ever expanding applications aimed at the elucidation of nucleic acid structure-function relationships. This Feature summarizes the current state of MS-based approaches devised to overcome the limitations of traditional techniques and to advance different facets of nucleic acids research.
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Affiliation(s)
- D Fabris
- The RNA Institute, University at Albany, Albany, NY 12222, USA.
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32
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Mayne SLN, Patterton HG. Bioinformatics tools for the structural elucidation of multi-subunit protein complexes by mass spectrometric analysis of protein-protein cross-links. Brief Bioinform 2011; 12:660-71. [PMID: 22101029 DOI: 10.1093/bib/bbq087] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Multi-subunit protein complexes are involved in many essential biochemical processes including signal transduction, protein synthesis, RNA synthesis, DNA replication and protein degradation. An accurate description of the relative structural arrangement of the constituent subunits in such complexes is crucial for an understanding of the molecular mechanism of the complex as a whole. Many complexes, however, lie in the mega-Dalton range, and are not amenable to X-ray crystallographic or nuclear magnetic resonance analysis. Techniques that are suited to structural studies of such large complexes, such as cryo-electron microscopy, do not provide the resolution required for a mechanistic insight. Mass spectrometry (MS) has increasingly been applied to identify the residues that are involved in chemical cross-links in compound protein assemblies, and have provided valuable insight into the molecular arrangement, orientation and contact surfaces of subunits within such large complexes. This approach is known as MS3D, and involves the MS analysis of cross-linked di-peptides following the enzymatic cleavage of a chemically cross-linked complex. A major challenge of this approach is the identification of the cross-linked di-peptides in a composite mixture of peptides, as well as the identification of the residues involved in the cross-link. These analyses require bioinformatics tools with capabilities beyond that of general, MS-based proteomic analysis software. Many MS3D software tools have appeared, often designed for very specific experimental methods. Here, we provide a review of all major MS3D bioinformatics programmes, reviewing their applicability to different workflows, specific experimental requirements and the computational approach taken by each.
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Affiliation(s)
- Shannon L N Mayne
- Department of Biotechnology, University of the Free State, Bloemfontein 9300, South Africa
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Smith SI, Brodbelt JS. Characterization of oligodeoxynucleotides and modifications by 193 nm photodissociation and electron photodetachment dissociation. Anal Chem 2011; 82:7218-26. [PMID: 20681614 DOI: 10.1021/ac100989q] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ultraviolet photodissociation (UVPD) at 193 nm is compared to collision induced dissociation (CID) for sequencing and determination of modifications of multideprotonated 6-20-mer oligodeoxynucleotides. UVPD at 193 nm causes efficient charge reduction of the deprotonated oligodeoxynucleotides via electron detachment, in addition to extensive backbone cleavages to yield sequence ions of relatively low abundance, including w, x, y, z, a, a-B, b, c, and d ions. Although internal ions populate UVPD spectra, base loss ions from the precursor are absent. Subsequent CID of the charge-reduced oligodeoxynucleotides formed upon electron detachment, in a net process called electron photodetachment dissociation (EPD), results in abundant sequence ions in terms of w, z, a, a-B, and d products, with a marked decrease in the abundance of precursor base loss ions and internal fragments. Complete sequencing was possible for virtually all oligodeoxynucleotides studied. EPD of three modified oligodeoxynucleotides, a methylated oligodeoxynucleotide, a phosphorothioate-modified oligodeoxynucleotide, and an ethylated-oligodeoxynucleotide, resulted in specific and extensive backbone cleavages, specifically, w, z, a, a-B, and d products, which allowed the modification site(s) to be pinpointed to a more specific location than by conventional CID.
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Affiliation(s)
- Suncerae I Smith
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA
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Fabris D, Yu ET. Elucidating the higher-order structure of biopolymers by structural probing and mass spectrometry: MS3D. JOURNAL OF MASS SPECTROMETRY : JMS 2010; 45:841-60. [PMID: 20648672 PMCID: PMC3432860 DOI: 10.1002/jms.1762] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Chemical probing represents a very versatile alternative for studying the structure and dynamics of substrates that are intractable by established high-resolution techniques. The implementation of MS-based strategies for the characterization of probing products has not only extended the range of applicability to virtually all types of biopolymers but has also paved the way for the introduction of new reagents that would not have been viable with traditional analytical platforms. As the availability of probing data is steadily increasing on the wings of the development of dedicated interpretation aids, powerful computational approaches have been explored to enable the effective utilization of such information to generate valid molecular models. This combination of factors has contributed to making the possibility of obtaining actual 3D structures by MS-based technologies (MS3D) a reality. Although approaches for achieving structure determination of unknown targets or assessing the dynamics of known structures may share similar reagents and development trajectories, they clearly involve distinctive experimental strategies, analytical concerns and interpretation paradigms. This Perspective offers a commentary on methods aimed at obtaining distance constraints for the modeling of full-fledged structures while highlighting common elements, salient distinctions and complementary capabilities exhibited by methods used in dynamics studies. We discuss critical factors to be addressed for completing effective structural determinations and expose possible pitfalls of chemical methods. We survey programs developed for facilitating the interpretation of experimental data and discuss possible computational strategies for translating sparse spatial constraints into all-atom models. Examples are provided to illustrate how the concerted application of very diverse probing techniques can lead to the solution of actual biological systems.
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Affiliation(s)
- Daniele Fabris
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, MD, USA.
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35
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The -galactosidase type A gene aglA from Aspergillus niger encodes a fully functional -N-acetylgalactosaminidase. Glycobiology 2010; 20:1410-9. [DOI: 10.1093/glycob/cwq105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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36
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Huang TY, Liu J, McLuckey SA. Top-down tandem mass spectrometry of tRNA via ion trap collision-induced dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:890-898. [PMID: 20080046 DOI: 10.1016/j.jasms.2009.12.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/15/2009] [Accepted: 12/16/2009] [Indexed: 05/28/2023]
Abstract
Transfer RNA is a class of highly modified and structured non-coding RNA molecules generally comprised of 74-95 nucleotides. In this study, tandem mass spectrometry of intact multiply charged tRNA anions of roughly 25 kDa in mass has been demonstrated using a quadrupole/time-of-flight tandem mass spectrometer adapted for ion/ion reaction studies. The sample proved to be a mixture of tRNA molecules. The mass of the most abundant component of the mixture was not consistent with that of the nominal identity of the tRNA from the supplier, viz., tRNA(Phe); rather, the mass was consistent with tRNA(Phe) bearing an incomplete 3'-terminus. Multiply-charged anions from the major components were isolated in the gas phase and subjected to ion trap collision-induced dissociation without subsequent ion/ion reactions. Abundant fragments from the 5'- and 3'-termini of the molecule could be used to identify the major component as tRNA(Phe)-3'adenosine (without 3'-phosphorylation). Roughly 15% of the primary sequence of the intact tRNA was unambiguously reflected in the product ion spectrum. The existence of a possible tRNA(Phe) variant and the intact tRNA(Phe) was also supported by ion trap CID data. The multiply-charged fragment ions derived from tRNA(Phe)-3'adenosine were further charge-reduced to mostly singly- and doubly-charged species via proton transfer ion/ion reactions with benzoquinoline cations. The resulting reduction in spectral overlap and charge state ambiguity simplified interpretation of the product ion spectrum and allowed for the identification of product ions from roughly 60% of the sequence.
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Affiliation(s)
- Teng-Yi Huang
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
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37
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Taucher M, Breuker K. Top-down mass spectrometry for sequencing of larger (up to 61 nt) RNA by CAD and EDD. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:918-929. [PMID: 20363646 DOI: 10.1016/j.jasms.2010.02.025] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 02/18/2010] [Accepted: 02/18/2010] [Indexed: 05/29/2023]
Abstract
We have studied the effect of solution additives on hydrolysis and charge state distribution in ESI MS of RNA. Lower and higher charge state ions can be electrosprayed from solutions containing 25 mM piperidine/25 mM imidazole and 1% vol. triethylamine, respectively, with base-catalyzed hydrolysis rates that are sufficiently slow to perform MS/MS experiments. These lower and higher charge state ions are suitable as precursors for CAD and EDD, respectively. We demonstrate nearly complete sequence coverage for 61 nt RNA dissociated by CAD, and 34 nt RNA dissociated by EDD, and suggest a mechanism for backbone fragmentation in EDD of RNA.
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Affiliation(s)
- Monika Taucher
- Institute of Organic Chemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Innsbruck, Austria
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38
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Gardner MW, Li N, Ellington AD, Brodbelt JS. Infrared multiphoton dissociation of small-interfering RNA anions and cations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:580-91. [PMID: 20129797 PMCID: PMC2847665 DOI: 10.1016/j.jasms.2009.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2009] [Revised: 12/21/2009] [Accepted: 12/22/2009] [Indexed: 05/13/2023]
Abstract
Infrared multiphoton dissociation (IRMPD) on a linear ion trap mass spectrometer is applied for the sequencing of small interfering RNA (siRNA). Both single-strand siRNAs and duplex siRNA were characterized by IRMPD, and the results were compared with that obtained by traditional ion trap-based collision induced dissociation (CID). The single-strand siRNA anions were observed to dissociate via cleavage of the 5' P-O bonds yielding c- and y-type product ions as well as undergo neutral base loss. Full sequence coverage of the siRNA anions was obtained by both IRMPD and CID. While the CID mass spectra were dominated by base loss ions, accounting for approximately 25% to 40% of the product ion current, these ions were eliminated through secondary dissociation by increasing the irradiation time in the IRMPD mass spectra to produce higher abundances of informative sequence ions. With longer irradiation times, however, internal ions corresponding to cleavage of two 5' P-O bonds began to populate the product ion mass spectra as well as higher abundances of [a - Base] and w-type ions. IRMPD of siRNA cations predominantly produced c- and y-type ions with minimal contributions of [a - Base] and w-type ions to the product ion current; the presence of only two complementary series of product ions in the IRMPD mass spectra simplified spectral interpretation. In addition, IRMPD produced high abundances of protonated nucleobases, [G + H](+), [A + H](+), and [C + H](+), which were not detected in the CID mass spectra due to the low-mass cut-off associated with conventional CID in ion traps. CID and IRMPD using short irradiation times of duplex siRNA resulted in strand separation, similar to the dissociation trends observed for duplex DNA. With longer irradiation times, however, the individual single-strands underwent secondary dissociation to yield informative sequence ions not obtained by CID.
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Affiliation(s)
- Myles W Gardner
- Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712-0165, USA
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39
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Fabris D. A role for the MS analysis of nucleic acids in the post-genomics age. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:1-13. [PMID: 19897384 DOI: 10.1016/j.jasms.2009.09.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2009] [Revised: 09/04/2009] [Accepted: 09/04/2009] [Indexed: 05/28/2023]
Abstract
The advances of mass spectrometry in the analysis of nucleic acids have tracked very closely the exciting developments of instrumentation and ancillary technologies, which have taken place over the years. However, their diffusion in the broader life sciences community has been and will be linked to the ever evolving focus of biomedical research and its changing demands. Before the completion of the Human Genome Project, great emphasis was placed on sequencing technologies that could help accomplish this project of exceptional scale. After the publication of the human genome, the emphasis switched toward techniques dedicated to the exploration of sequences not coding for actual protein products, which amount to the vast majority of transcribed elements. The broad range of capabilities offered by mass spectrometry is rapidly advancing this platform to the forefront of the technologies employed for the structure-function investigation of these noncoding elements. Increasing focus on the characterization of functional assemblies and their specific interactions has prompted a re-evaluation of what has been traditionally construed as nucleic acid analysis by mass spectrometry. Inspired by the accelerating expansion of the broader field of nucleic acid research, new applications to fundamental biological studies and drug discovery will help redefine the evolving role of MS-analysis of nucleic acids in the post-genomics age.
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Affiliation(s)
- Daniele Fabris
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21228, USA.
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40
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Oberacher H. Frontiers of mass spectrometry in nucleic acids analysis. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2010; 16:351-365. [PMID: 20530841 DOI: 10.1255/ejms.1045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Nucleic acids research is a highly competitive field of research. A number of well established methods are available. The current output of high throughput ("next generation") sequencing technologies is impressive, and still technologies are continuing to make progress regarding read lengths, bp per second, accuracy and costs. Although in the 1990s MS was considered as an analytical platform for sequencing, it was soon realized that MS will never be competitive. Thus, the focus shifted from de novo sequencing towards other areas of application where MS has proven to be a powerful analytical tool. Potential niches for the application of MS in nucleic acids research include genotyping of genetic markers (single nucleotide polymorphisms, short tandem repeats, and combinations thereof), quality control of synthetic oligonucleotides, metabolic profiling of therapeutics, characterization of modified nucleobases in DNA and RNA molecules, and the study of non covalent interactions among nucleic acids as well as interactions of nucleic acids with drugs and proteins. The diversity of possible applications for MS highlights its significance for nucleic acid research.
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Affiliation(s)
- Herbert Oberacher
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria.
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41
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Pompach P, Man P, Kavan D, Hofbauerová K, Kumar V, Bezouska K, Havlícek V, Novák P. Modified electrophoretic and digestion conditions allow a simplified mass spectrometric evaluation of disulfide bonds. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:1571-1578. [PMID: 19551705 DOI: 10.1002/jms.1609] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Proper formation of disulfide bonds in proteins is a prerequisite to their stability and function. Information on disulfide pattern may therefore serve as an indication of the proper folding of recombinant proteins, and can also be used in protein homology modeling for the purpose of structure refinement. Protein handling and digestion at basic pH leads to disulfide bond scrambling. That is why the samples are usually treated and digested at low pH where no scrambling occurs. Unfortunately, the specific proteases used in protein research are active at high pH values. Here, we present a complete sample handling protocol, which allows processing of disulfide containing proteins at basic pH. We modified the standard SDS gel electrophoresis and protein digestion conditions by the addition of an oxidative agent, cystamine. This modification prevented disulfide scrambling, which we otherwise observed in the samples handled according to the general protocol. Lysozyme from hen egg was used as a model protein for the development of the method. We then applied our protocol to human leukocyte antigen CD69, for which the disulfide bonding is known, but only for its monomeric form. In addition, the disulfide arrangement was then 'de novo' identified in the recombinant murine leukocyte receptor NKR-P1A and in the larger glycosylated proteins beta-N-acetylhexosaminidases from Aspergillus oryzae and Penicillium oxalicum.
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Affiliation(s)
- Petr Pompach
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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42
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Smith S, Guziec FS, Guziec L, Brodbelt JS. Interactions of sulfur-containing acridine ligands with DNA by ESI-MS. Analyst 2009; 134:2058-66. [PMID: 19768213 PMCID: PMC2892893 DOI: 10.1039/b905071j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The alkylating proficiency of sulfur-containing mustards may be increased by using an acridine moiety to guide the sulfur mustard to its cellular target. In this study, the interactions of a new series of sulfur-containing acridine ligands, some that also function as alkylating mustards, with DNA were evaluated by electrospray ionization mass spectrometry (ESI-MS). Relative binding affinities were estimated from the ESI-MS data based on the fraction of bound DNA for DNA/acridine mixtures. The extent of binding observed for the series of sulfur-containing acridines was similar, presumably because the intercalating acridine moiety was identical. Upon infrared multi-photon dissociation (IRMPD) of the resulting oligonucleotide/sulfur-containing acridine complexes, ejection of the ligand was the dominant pathway for most of the complexes. However, for AS4, an acridine sulfide mustard, and AN1, an acridine nitrogen mustard, strand separation with the ligand remaining on one of the single strands was observed. At higher irradiation times, a variety of sequence ions were observed, some retaining the AS4/AN1 ligand, which was indicative of covalent binding.
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Affiliation(s)
- Suncerae Smith
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712
| | - Frank S. Guziec
- Department of Chemistry, Southwestern University, Georgetown, TX 79626
| | - Lynn Guziec
- Department of Chemistry, Southwestern University, Georgetown, TX 79626
| | - Jennifer S. Brodbelt
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712
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43
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Turner KB, Yi-Brunozzi HY, Brinson RG, Marino JP, Fabris D, Le Grice SFJ. SHAMS: combining chemical modification of RNA with mass spectrometry to examine polypurine tract-containing RNA/DNA hybrids. RNA (NEW YORK, N.Y.) 2009; 15:1605-1613. [PMID: 19535461 PMCID: PMC2714758 DOI: 10.1261/rna.1615409] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Accepted: 04/29/2009] [Indexed: 05/27/2023]
Abstract
Selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) has gained popularity as a facile method of examining RNA structure both in vitro and in vivo, exploiting accessibility of the ribose 2'-OH to acylation by N-methylisatoic anhydride (NMIA) in unpaired or flexible configurations. Subsequent primer extension terminates at the site of chemical modification, and these products are fractionated by high-resolution gel electrophoresis. When applying SHAPE to investigate structural features associated with the wild-type and analog-substituted polypurine tract (PPT)-containing RNA/DNA hybrids, their size (20-25 base pairs) rendered primer extension impractical. As an alternative method of detection, we reasoned that chemical modification could be combined with tandem mass spectrometry, relying on the mass increment of RNA fragments containing the NMIA adduct (M(r) = 133 Da). Using this approach, we demonstrate both specific modification of the HIV-1 PPT RNA primer and variations in its acylation pattern induced by replacing template nucleotides with a non-hydrogen-bonding thymine isostere. Our selective 2'-hydroxyl acylation analyzed by mass spectrometry strategy (SHAMS) should find utility when examining the structure of small RNA fragments or RNA/DNA hybrids where primer extension cannot be performed.
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Affiliation(s)
- Kevin B Turner
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, USA
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44
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Oberacher H, Pitterl F. On the use of ESI-QqTOF-MS/MS for the comparative sequencing of nucleic acids. Biopolymers 2009; 91:401-9. [PMID: 19189378 DOI: 10.1002/bip.21156] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The usability of a quadrupole-quadrupole-time-of-flight (QqTOF) instrument for the tandem mass spectrometric sequencing of oligodeoxynuleotides was investigated. The sample set consisted of 21 synthetic oligodeoxynucleotides ranging in length from 5 to 42 nucleotides. The sequences were randomly selected. For the majority of tested oligonucleotides, two or three different charge states were selected as precursor ions. Each precursor ion was fragmented applying several different collision voltages. Overall 282 fragment ion mass spectra were acquired. Computer-aided interpretation of fragment ion mass spectra was accomplished with a recently introduced comparative sequencing algorithm (COMPAS). The applied version of COMPAS was specifically optimized for the interpretation of information-rich spectra obtained on the QqTOF. Sequences of oligodeoxynucleotides as large as 26-mers were correctly verified in >94% of cases (182 of 192 spectra acquired). Fragment ion mass spectra of larger oligonucleotides were not specific enough for sequencing. Because of the occurrence of extensive internal fragmentation causing low sequence coverage paired with a high probability of assigning fragment ions to wrong sequences, tandem mass spectra obtained from oligonucleotides consisting of 30 and more nucleotides could not be used for sequence verification neither manually nor with COMPAS. (c) 2009 Wiley Periodicals, Inc. Biopolymers 91: 401-409, 2009.
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Affiliation(s)
- Herbert Oberacher
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria.
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45
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Liao Q, Shen C, Vouros P. GenoMass--a computer software for automated identification of oligonucleotide DNA adducts from LC-MS analysis of DNA digests. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:549-560. [PMID: 19053159 PMCID: PMC2752885 DOI: 10.1002/jms.1532] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In the investigation of oligonucleotides, DNA and their adducts by LC-MS, a myriad of data are generated that make manual data processing quite difficult. This paper describes a 'reversed pseudo-combinatorial' approach for fragment identification and the software implementation of this approach. Combinatorial isomer libraries are generated in silico to represent the digestion products of oligonucleotides, DNA or DNA adducts of various sizes. The software automatically calculates ion masses of each isomeric segment of the library, searches for them in complicated LC-MS data, lists their intensities and plots extracted ion chromatograms (EIC). This customized new data analysis tool has enabled a study of the enzymatic behavior of a nuclease system in the digestion of normal and adducted DNA, and in the recognition of oligomers containing a carcinogen bound to a nucleobase. The software program potentially can be further expanded to postulate unknown DNA sequences and recognize the adduction sites.
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Affiliation(s)
- Qing Liao
- Mass Spectrometry Center, FAS Center for System Biology, Harvard University, Cambridge, MA 02138, USA
| | | | - Paul Vouros
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA
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46
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Xu Y, Afonso C, Wen R, Tabet JC. Investigation of double-stranded DNA/drug interaction by ESI/FT ICR: orientation of dissociations relates to stabilizing salt bridges. JOURNAL OF MASS SPECTROMETRY : JMS 2008; 43:1531-1544. [PMID: 18521852 DOI: 10.1002/jms.1430] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Noncovalent complexes of DNA and Hoechst 33258 were investigated by ESI-FT/ICR MS in various activation modes (collision-induced dissociation (CID), sustained off-resonance irradiation collision-induced dissociation (SORI-CID), infrared multiphoton dissociation (IRMPD) and electron detachment dissociation (EDD)). The binding selectivity of Hoechst 33258 was confirmed by the comparative study of its noncovalent association with different DNA sequences. The CID spectra of [ds + HO - 5H](5-) obtained with a linear hexapole ion trap resulted in unzipping of the strands. This outcome is a clue to the drug-binding mode, shading light on the localization of the binding sites of Hoechst 33258 to the DNA sequence. The IRMPD and SORI-CID experiments mainly gave DNA backbone cleavages and internal fragment ions. From this result, information on the localization of the binding sites of Hoechst 33258 in the DNA sequence was obtained. No sodium cationization was observed on the DNA sequence ions although they were present on fragmentation of the duplex, indicating that the backbone cleavages were generated from the single strand associated with the Hoechst 33258 where the number of alkali cation is restricted. Under electron detachment (ED) conditions, multiple EDs were achieved for the [ds + HO - 5H](5-) ion without any significant dissociation. The presence of drug appears to enhance the stability of the multiply charged system. It was proposed that the studied noncovalent complex involved the formation of zwitterions and consequently strong salt-bridge interactions between DNA and drug.
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Affiliation(s)
- Ying Xu
- Université Pierre et Marie Curie-Paris 6, UMR 7613 Synthèse, Structure et Fonction de Molécules Bioactives, Paris, F-75005, France
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47
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Yu ET, Hawkins A, Kuntz ID, Rahn LA, Rothfuss A, Sale K, Young MM, Yang CL, Pancerella CM, Fabris D. The collaboratory for MS3D: a new cyberinfrastructure for the structural elucidation of biological macromolecules and their assemblies using mass spectrometry-based approaches. J Proteome Res 2008; 7:4848-57. [PMID: 18817429 DOI: 10.1021/pr800443f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Modern biomedical research is evolving with the rapid growth of diverse data types, biophysical characterization methods, computational tools and extensive collaboration among researchers spanning various communities and having complementary backgrounds and expertise. Collaborating researchers are increasingly dependent on shared data and tools made available by other investigators with common interests, thus forming communities that transcend the traditional boundaries of the single research laboratory or institution. Barriers, however, remain to the formation of these virtual communities, usually due to the steep learning curve associated with becoming familiar with new tools, or with the difficulties associated with transferring data between tools. Recognizing the need for shared reference data and analysis tools, we are developing an integrated knowledge environment that supports productive interactions among researchers. Here we report on our current collaborative environment, which focuses on bringing together structural biologists working in the area of mass spectrometric based methods for the analysis of tertiary and quaternary macromolecular structures (MS3D) called the Collaboratory for MS3D (C-MS3D). C-MS3D is a Web-portal designed to provide collaborators with a shared work environment that integrates data storage and management with data analysis tools. Files are stored and archived along with pertinent meta data in such a way as to allow file handling to be tracked (data provenance) and data files to be searched using keywords and modification dates. While at this time the portal is designed around a specific application, the shared work environment is a general approach to building collaborative work groups. The goal of this is to not only provide a common data sharing and archiving system, but also to assist in the building of new collaborations and to spur the development of new tools and technologies.
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Affiliation(s)
- Eizadora T Yu
- Biosystems Research, Advanced Software R&D, and Exploratory Computer and Software Engineering Departments, Sandia National Laboratories, P.O. Box 969, Livermore, California 94551-0969, USA
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Abstract
The structure of HIV-1 Psi-RNA has been elucidated by a concerted approach combining structural probes with mass spectrometric detection (MS3D), which is not affected by the size and crystallization properties of target biomolecules. Distance constraints from bifunctional cross-linkers provided the information required for assembling an all-atom model from the high-resolution coordinates of separate domains by triangulating their reciprocal placement in 3D space. The resulting structure revealed a compact cloverleaf morphology stabilized by a long-range tertiary interaction between the GNRA tetraloop of stemloop 4 (SL4) and the upper stem of stemloop 1 (SL1). The preservation of discrete stemloop structures ruled out the possibility that major rearrangements might produce a putative supersite with enhanced affinity for the nucleocapsid (NC) domain of the viral Gag polyprotein, which would drive genome recognition and packaging. The steric situation of single-stranded regions exposed on the cloverleaf structure offered a valid explanation for the stoichiometry exhibited by full-length Psi-RNA in the presence of NC. The participation of SL4 in a putative GNRA loop-receptor interaction provided further indications of the plasticity of this region of genomic RNA, which can also anneal with upstream sequences to stabilize alternative conformations of the 5' untranslated region (5'-UTR). Considering the ability to sustain specific NC binding, the multifaceted activities supported by the SL4 sequence suggest a mechanism by which Gag could actively participate in regulating the vital functions mediated by 5'-UTR. Substantiated by the 3D structure of Psi-RNA, the central role played by SL4 in specific RNA-RNA and protein-RNA interactions advances this domain as a primary target for possible therapeutic intervention.
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Rosu F, De Pauw E, Gabelica V. Electrospray mass spectrometry to study drug-nucleic acids interactions. Biochimie 2008; 90:1074-87. [DOI: 10.1016/j.biochi.2008.01.005] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Accepted: 01/11/2008] [Indexed: 12/27/2022]
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Zhang Q, Crosland E, Fabris D. Nested Arg-specific bifunctional crosslinkers for MS-based structural analysis of proteins and protein assemblies. Anal Chim Acta 2008; 627:117-28. [PMID: 18790135 DOI: 10.1016/j.aca.2008.05.074] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 05/28/2008] [Accepted: 05/28/2008] [Indexed: 01/14/2023]
Abstract
The combination of chemical probing and high-resolution mass spectrometry constitutes a powerful alternative for the structural elucidation of biomolecules possessing unfavorable size, solubility, and flexibility. We have developed nested Arg-specific bifunctional crosslinkers to obtain complementary information to typical Cys- and Lys-specific reagents available on the market. The structures of 1,4-phenyl-diglyoxal (PDG) and 4,4'-biphenyl-diglyoxal (BDG) include two identical 1,2-dicarbonyl functions capable of reacting with the guanido group of Arg residues in proteins, as well as the base-pairing face of guanine in nucleic acids. The reactive functions are separated by modular spacers consisting of one or two benzene rings, which confer greater rigidity to the crosslinker structure than it is afforded by typical aliphatic spacers. Analysis by electrospray ionization (ESI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has shown that the probes provide both mono- and bifunctional products with model protein substrates, which are stabilized by the formation of diester derivatives in the presence of borate buffer. The identification of crosslinked sites was accomplished by employing complementary proteolytic procedures and peptide mapping by ESI-FTICR. The results showed excellent correlation with the solvent accessibility and structural context of susceptible residues, and highlighted the significance of possible dynamic effects in determining the outcome of crosslinking reactions. The application of nested reagents with different spacing has provided a new tool for experimentally recognizing flexible regions that may be involved in prominent dynamics in solution. The development of new bifunctional crosslinkers with diverse target specificity and different bridging spans is expected to facilitate the structure elucidation of progressively larger biomolecular assemblies by increasing the number and diversity of spatial constraints available for triangulating the position of crosslinked structures in the three dimensions.
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Affiliation(s)
- Qingrong Zhang
- University of Maryland Baltimore County, Baltimore, MD 21228, United States
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