1
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Characterization of protein unfolding by fast cross-linking mass spectrometry using di-ortho-phthalaldehyde cross-linkers. Nat Commun 2022; 13:1468. [PMID: 35304446 PMCID: PMC8933431 DOI: 10.1038/s41467-022-28879-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 02/10/2022] [Indexed: 01/16/2023] Open
Abstract
Chemical cross-linking of proteins coupled with mass spectrometry is widely used in protein structural analysis. In this study we develop a class of non-hydrolyzable amine-selective di-ortho-phthalaldehyde (DOPA) cross-linkers, one of which is called DOPA2. Cross-linking of proteins with DOPA2 is 60-120 times faster than that with the N-hydroxysuccinimide ester cross-linker DSS. Compared with DSS cross-links, DOPA2 cross-links show better agreement with the crystal structures of tested proteins. More importantly, DOPA2 has unique advantages when working at low pH, low temperature, or in the presence of denaturants. Using staphylococcal nuclease, bovine serum albumin, and bovine pancreatic ribonuclease A, we demonstrate that DOPA2 cross-linking provides abundant spatial information about the conformations of progressively denatured forms of these proteins. Furthermore, DOPA2 cross-linking allows time-course analysis of protein conformational changes during denaturant-induced unfolding.
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2
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Trahan C, Oeffinger M. Targeted Cross-Linking Mass Spectrometry on Single-Step Affinity Purified Molecular Complexes in the Yeast Saccharomyces cerevisiae. Methods Mol Biol 2022; 2456:185-210. [PMID: 35612743 DOI: 10.1007/978-1-0716-2124-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Protein cross-linking mass spectrometry (XL-MS) has been developed into a powerful and robust tool that is now well implemented and routinely used by an increasing number of laboratories. While bulk cross-linking of complexes provides useful information on whole complexes, it is limiting for the probing of specific protein "neighbourhoods," or vicinity interactomes. For example, it is not unusual to find cross-linked peptide pairs that are disproportionately overrepresented compared to the surface areas of complexes, while very few or no cross-links are identified in other regions. When studying dynamic complexes along their pathways, some vicinity cross-links may be of too low abundance in the pool of heterogenous complexes of interest to be efficiently identified by standard XL-MS. In this chapter, we describe a targeted XL-MS approach from single-step affinity purified (ssAP) complexes that enables the investigation of specific protein "neighbourhoods" within molecular complexes in yeast, using a small cross-linker anchoring tag, the CH-tag. One advantage of this method over a general cross-linking strategy is the possibility to significantly enrich for localized anchored-cross-links within complexes, thus yielding a higher sensitivity to detect highly dynamic or low abundance protein interactions within a specific protein "neighbourhood" occurring along the pathway of a selected bait protein. Moreover, many variations of the method can be employed; the ssAP-tag and the CH-tag can either be fused to the same or different proteins in the complex, or the CH-tag can be fused to multiple protein components in the same cell line to explore dynamic vicinity interactions along a pathway.
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Affiliation(s)
- Christian Trahan
- Institut de recherches cliniques de Montréal, Montréal, QC, Canada
| | - Marlene Oeffinger
- Institut de recherches cliniques de Montréal, Montréal, QC, Canada.
- Département de biochimie, Faculté de médecine, Université de Montréal, Montréal, QC, Canada.
- Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, Canada.
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3
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Misal SA, Zhao B, Reilly JP. Interpretation of Anomalously Long Crosslinks in Ribosome Crosslinking reveals the ribosome interaction in stationary phase E. coli. RSC Chem Biol 2022; 3:886-894. [PMID: 35866168 PMCID: PMC9257603 DOI: 10.1039/d2cb00101b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/15/2022] [Indexed: 11/21/2022] Open
Abstract
Crosslinking mass spectrometry (XL-MS) of bacterial ribosomes revealed the dynamic intra and intermolecular interactions within the ribosome structure. It has been also extended to capture the interactions of ribosome binding...
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Affiliation(s)
- Santosh A Misal
- Department of Chemistry, Indiana University 800 East Kirkwood Avenue Bloomington IN 47405 USA
| | - Bingqing Zhao
- Department of Chemistry, Indiana University 800 East Kirkwood Avenue Bloomington IN 47405 USA
| | - James P Reilly
- Department of Chemistry, Indiana University 800 East Kirkwood Avenue Bloomington IN 47405 USA
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4
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Zhao B, Reilly CP, Davis C, Matouschek A, Reilly JP. Use of Multiple Ion Fragmentation Methods to Identify Protein Cross-Links and Facilitate Comparison of Data Interpretation Algorithms. J Proteome Res 2020; 19:2758-2771. [PMID: 32496805 DOI: 10.1021/acs.jproteome.0c00111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Multiple ion fragmentation methods involving collision-induced dissociation (CID), higher-energy collisional dissociation (HCD) with regular and very high energy settings, and electron-transfer dissociation with supplementary HCD (EThcD) are implemented to improve the confidence of cross-link identifications. Three different S. cerevisiae proteasome samples cross-linked by diethyl suberthioimidate (DEST) or bis(sulfosuccinimidyl)suberate (BS3) are analyzed. Two approaches are introduced to combine interpretations from the above four methods. Working with cleavable cross-linkers such as DEST, the first approach searches for cross-link diagnostic ions and consistency among the best interpretations derived from all four MS2 spectra associated with each precursor ion. Better agreement leads to a more definitive identification. Compatible with both cleavable and noncleavable cross-linkers such as BS3, the second approach multiplies scoring metrics from a number of fragmentation experiments to derive an overall best match. This significantly increases the scoring gap between the target and decoy matches. The validity of cross-links fragmented by HCD alone and identified by Kojak, MeroX, pLink, and Xi was evaluated using multiple fragmentation data. Possible ways to improve the identification credibility are discussed. Data are available via ProteomeXchange with identifier PXD018310.
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Affiliation(s)
- Bingqing Zhao
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Colin P Reilly
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Caroline Davis
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Andreas Matouschek
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas 78712, United States
| | - James P Reilly
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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5
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Zhao B, Reilly CP, Reilly JP. ETD-Cleavable Linker for Confident Cross-linked Peptide Identifications. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:1631-1642. [PMID: 31098958 DOI: 10.1007/s13361-019-02227-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 06/09/2023]
Abstract
Peptide cross-links formed using the homobifunctional-linker diethyl suberthioimidate (DEST) are shown to be ETD-cleavable. DEST has a spacer arm consisting of a 6-carbon alkyl chain and it cleaves at the amidino groups created upon reaction with primary amines. In ETD MS2 spectra, DEST cross-links can be recognized based on mass pairs consisting of peptide-NH2• and peptide+linker+NH3 ions, and backbone cleavages are more equally distributed over the two constituent peptides compared with collisional activation. Dead ends that are often challenging to distinguish from cross-links are diagnosed by intense reporter ions. ETD mass pairs can be used in MS3 experiments to confirm cross-link identifications. These features provide a simple but reliable approach to identify cross-links that should facilitate studies of protein complexes.
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Affiliation(s)
- Bingqing Zhao
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Colin P Reilly
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - James P Reilly
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN, 47405, USA.
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6
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Chavez JD, Bruce JE. Chemical cross-linking with mass spectrometry: a tool for systems structural biology. Curr Opin Chem Biol 2018; 48:8-18. [PMID: 30172868 DOI: 10.1016/j.cbpa.2018.08.006] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/09/2018] [Accepted: 08/10/2018] [Indexed: 01/14/2023]
Abstract
Biological processes supporting life are orchestrated by a highly dynamic array of protein structures and interactions comprising the interactome. Defining the interactome, visualizing how structures and interactions change and function to support life is essential to improved understanding of fundamental molecular processes, but represents a challenge unmet by any single analytical technique. Chemical cross-linking with mass spectrometry provides identification of proximal amino acid residues within proteins and protein complexes, yielding low resolution structural information. This approach has predominantly been employed to provide structural insight on isolated protein complexes, and has been particularly useful for molecules that are recalcitrant to conventional structural biology studies. Here we discuss recent developments in cross-linking and mass spectrometry technologies that are providing large-scale or systems-level interactome data with successful applications to isolated organelles, cell lysates, virus particles, intact bacterial and mammalian cultured cells and tissue samples.
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Affiliation(s)
- Juan D Chavez
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - James E Bruce
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA.
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7
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Zhang X, Wang JH, Tan D, Li Q, Li M, Gong Z, Tang C, Liu Z, Dong MQ, Lei X. Carboxylate-Selective Chemical Cross-Linkers for Mass Spectrometric Analysis of Protein Structures. Anal Chem 2018; 90:1195-1201. [DOI: 10.1021/acs.analchem.7b03789] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Xiaoyun Zhang
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
Synthetic and Functional Biomolecules Center, and Peking-Tsinghua
Center for Life Sciences, Peking University, Beijing 100871, China
| | - Jian-Hua Wang
- Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
- National Institute of Biological Sciences (NIBS), Beijing 102206, China
| | - Dan Tan
- National Institute of Biological Sciences (NIBS), Beijing 102206, China
| | - Qiang Li
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
Synthetic and Functional Biomolecules Center, and Peking-Tsinghua
Center for Life Sciences, Peking University, Beijing 100871, China
| | - Maodong Li
- Center
for Quantitative Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zhou Gong
- CAS
Key Laboratory of Magnetic Resonance in Biological Systems, State
Key Laboratory of Magnetic Resonance and Atomic Molecular Physics,
National Center for Magnetic Resonance at Wuhan, Wuhan Institute of Physics and Mathematics of the Chinese Academy of Sciences, Wuhan, Hubei Province 430071, China
| | - Chun Tang
- CAS
Key Laboratory of Magnetic Resonance in Biological Systems, State
Key Laboratory of Magnetic Resonance and Atomic Molecular Physics,
National Center for Magnetic Resonance at Wuhan, Wuhan Institute of Physics and Mathematics of the Chinese Academy of Sciences, Wuhan, Hubei Province 430071, China
| | - Zhirong Liu
- Center
for Quantitative Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Meng-Qiu Dong
- Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
- National Institute of Biological Sciences (NIBS), Beijing 102206, China
| | - Xiaoguang Lei
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
Synthetic and Functional Biomolecules Center, and Peking-Tsinghua
Center for Life Sciences, Peking University, Beijing 100871, China
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8
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Rozbeský D, Rosůlek M, Kukačka Z, Chmelík J, Man P, Novák P. Impact of Chemical Cross-Linking on Protein Structure and Function. Anal Chem 2018; 90:1104-1113. [DOI: 10.1021/acs.analchem.7b02863] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel Rozbeský
- Institute of Microbiology, v.v.i., Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
| | - Michal Rosůlek
- Institute of Microbiology, v.v.i., Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
| | - Zdeněk Kukačka
- Institute of Microbiology, v.v.i., Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
| | - Josef Chmelík
- Institute of Microbiology, v.v.i., Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
| | - Petr Man
- Institute of Microbiology, v.v.i., Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
| | - Petr Novák
- Institute of Microbiology, v.v.i., Czech Academy of Sciences, 14220 Prague, Czech Republic
- Department
of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
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9
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Barysz HM, Malmström J. Development of Large-scale Cross-linking Mass Spectrometry. Mol Cell Proteomics 2017; 17:1055-1066. [PMID: 28389583 DOI: 10.1074/mcp.r116.061663] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 03/26/2017] [Indexed: 11/06/2022] Open
Abstract
Cross-linking mass spectrometry (CLMS) provides distance constraints to study the structure of proteins, multiprotein complexes and protein-protein interactions which are critical for the understanding of protein function. CLMS is an attractive technology to bridge the gap between high-resolution structural biology techniques and proteomic-based interactome studies. However, as outlined in this review there are still several bottlenecks associated with CLMS which limit its application on a proteome-wide level. Specifically, there is an unmet need for comprehensive software that can reliably identify cross-linked peptides from large data sets. In this review we provide supporting information to reason that targeted proteomics of cross-links may provide the required sensitivity to reliably detect and quantify cross-linked peptides and that a reporter ion signature for cross-linked peptides may become a useful approach to increase confidence in the identification process of cross-linked peptides. In addition, the review summarizes the recent advances in CLMS workflows using the analysis of condensin complex in intact chromosomes as a model complex.
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Affiliation(s)
- Helena Maria Barysz
- From the ‡Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Johan Malmström
- From the ‡Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
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10
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Vandermarliere E, Stes E, Gevaert K, Martens L. Resolution of protein structure by mass spectrometry. MASS SPECTROMETRY REVIEWS 2016; 35:653-665. [PMID: 25536908 DOI: 10.1002/mas.21450] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/14/2014] [Indexed: 06/04/2023]
Abstract
Typically, mass spectrometry is used to identify the peptides present in a complex peptide mixture and subsequently the precursor proteins. As such, mass spectrometry focuses mainly on the primary structure, the (modified) amino acid sequence of peptides and proteins. In contrast, the three-dimensional structure of a protein is typically determined with protein X-ray crystallography or NMR. Despite the close relationship between these two aspects of protein studies (sequence and structure), mass spectrometry and structure determination are not frequently combined. Nevertheless, this combination of approaches, dubbed conformational proteomics, can offer insight into the function, working mechanism, and conformational status of a protein. In this review, we will discuss the developments at the intersection of mass spectrometry-based proteomics and protein structure determination and start from a brief overview of the classic approaches to identify protein structure along with their advantages and disadvantages. We will subsequently discuss the ability of mass spectrometry to overcome some of the hurdles of these classic methods. Finally, we will provide an outlook on the interplay of mass spectrometry and protein structure determination, and highlight several recent experiments in which mass spectrometry was successfully used to either aid or complement structure elucidation. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 35:653-665, 2016.
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Affiliation(s)
- Elien Vandermarliere
- Department of Medical Protein Research, VIB, B-9000, Ghent, Belgium
- Department of Biochemistry, Ghent University, B- 9000, Ghent, Belgium
| | - Elisabeth Stes
- Department of Medical Protein Research, VIB, B-9000, Ghent, Belgium
- Department of Biochemistry, Ghent University, B- 9000, Ghent, Belgium
| | - Kris Gevaert
- Department of Medical Protein Research, VIB, B-9000, Ghent, Belgium
- Department of Biochemistry, Ghent University, B- 9000, Ghent, Belgium
| | - Lennart Martens
- Department of Medical Protein Research, VIB, B-9000, Ghent, Belgium.
- Department of Biochemistry, Ghent University, B- 9000, Ghent, Belgium.
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11
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Ji C, Li S, Reilly JP, Radivojac P, Tang H. XLSearch: a Probabilistic Database Search Algorithm for Identifying Cross-Linked Peptides. J Proteome Res 2016; 15:1830-41. [PMID: 27068484 PMCID: PMC5770149 DOI: 10.1021/acs.jproteome.6b00004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical cross-linking combined with mass spectrometric analysis has become an important technique for probing protein three-dimensional structure and protein-protein interactions. A key step in this process is the accurate identification and validation of cross-linked peptides from tandem mass spectra. The identification of cross-linked peptides, however, presents challenges related to the expanded nature of the search space (all pairs of peptides in a sequence database) and the fact that some peptide-spectrum matches (PSMs) contain one correct and one incorrect peptide but often receive scores that are comparable to those in which both peptides are correctly identified. To address these problems and improve detection of cross-linked peptides, we propose a new database search algorithm, XLSearch, for identifying cross-linked peptides. Our approach is based on a data-driven scoring scheme that independently estimates the probability of correctly identifying each individual peptide in the cross-link given knowledge of the correct or incorrect identification of the other peptide. These conditional probabilities are subsequently used to estimate the joint posterior probability that both peptides are correctly identified. Using the data from two previous cross-link studies, we show the effectiveness of this scoring scheme, particularly in distinguishing between true identifications and those containing one incorrect peptide. We also provide evidence that XLSearch achieves more identifications than two alternative methods at the same false discovery rate (availability: https://github.com/COL-IU/XLSearch ).
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Affiliation(s)
- Chao Ji
- Department of Computer Science and Informatics, Indiana University, Bloomington, Indiana 47405, United States
| | - Sujun Li
- Department of Computer Science and Informatics, Indiana University, Bloomington, Indiana 47405, United States
| | - James P. Reilly
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Predrag Radivojac
- Department of Computer Science and Informatics, Indiana University, Bloomington, Indiana 47405, United States
| | - Haixu Tang
- Department of Computer Science and Informatics, Indiana University, Bloomington, Indiana 47405, United States
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12
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Tan D, Li Q, Zhang MJ, Liu C, Ma C, Zhang P, Ding YH, Fan SB, Tao L, Yang B, Li X, Ma S, Liu J, Feng B, Liu X, Wang HW, He SM, Gao N, Ye K, Dong MQ, Lei X. Trifunctional cross-linker for mapping protein-protein interaction networks and comparing protein conformational states. eLife 2016; 5. [PMID: 26952210 PMCID: PMC4811778 DOI: 10.7554/elife.12509] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 02/26/2016] [Indexed: 12/20/2022] Open
Abstract
To improve chemical cross-linking of proteins coupled with mass spectrometry (CXMS), we developed a lysine-targeted enrichable cross-linker containing a biotin tag for affinity purification, a chemical cleavage site to separate cross-linked peptides away from biotin after enrichment, and a spacer arm that can be labeled with stable isotopes for quantitation. By locating the flexible proteins on the surface of 70S ribosome, we show that this trifunctional cross-linker is effective at attaining structural information not easily attainable by crystallography and electron microscopy. From a crude Rrp46 immunoprecipitate, it helped identify two direct binding partners of Rrp46 and 15 protein-protein interactions (PPIs) among the co-immunoprecipitated exosome subunits. Applying it to E. coli and C. elegans lysates, we identified 3130 and 893 inter-linked lysine pairs, representing 677 and 121 PPIs. Using a quantitative CXMS workflow we demonstrate that it can reveal changes in the reactivity of lysine residues due to protein-nucleic acid interaction. DOI:http://dx.doi.org/10.7554/eLife.12509.001 Proteins fold into structures that are determined by the order of the amino acids that they are built from. These structures enable the protein to carry out its role, which often involves interacting with other proteins. Chemical cross-linking coupled with mass spectrometry (CXMS) is a powerful method used to study protein structure and how proteins interact, with a benefit of stabilizing and capturing brief interactions. CXMS uses a chemical compound called a linker that has two arms, each of which can bind specific amino acids in a protein or in multiple proteins. Only when the regions are close to each other can they be “cross-linked” in this way. After cross-linking, the proteins are cut into small pieces known as peptides. The cross-linked peptides are then separated from the non cross-linked ones and characterized. Although CXMS is a popular method, there are aspects about it that limit its use. It does not work well on complex samples that contain lots of different proteins, as it is difficult to separate the cross-linked peptides from the overwhelming amounts of non cross-linked peptides. Also, although it can be used to detect changes in the shape of a protein, which are often crucial to the protein's role, the method has not been smoothed out. Tan, Li et al. have now developed a new cross-linker called Leiker that addresses these limitations. Leiker cross-links the amino acid lysine to another lysine, and contains a molecular tag that allows cross-linked peptides to be efficiently purified away from non cross-linked peptides. As part of a streamlined workflow to detect changes in the shape of a protein, Leiker also contains a region that can be labeled. Analysing a bacterial ribosome, which contains more than 50 proteins, showed that Leiker-based CXMS could detect many more protein interactions than previous studies had. These included interactions that changed too rapidly to be studied by other structural methods. Tan, Li et al. then applied Leiker-based CXMS to the entire contents of bacterial cells at different stages of growth, and identified a protein interaction that is only found in growing cells. In future, Leiker will be useful for analyzing the structure of large protein complexes, probing changes in protein structure, and mapping the interactions between proteins in complex mixtures. DOI:http://dx.doi.org/10.7554/eLife.12509.002
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Affiliation(s)
- Dan Tan
- Graduate Program, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.,National Institute of Biological Sciences, Beijing, China
| | - Qiang Li
- National Institute of Biological Sciences, Beijing, China.,Synthetic and Functional Biomolecules Center, Peking University, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.,Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Mei-Jun Zhang
- National Institute of Biological Sciences, Beijing, China
| | - Chao Liu
- Key Lab of Intelligent Information Processing of Chinese Academy of Sciences, Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Chengying Ma
- Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Pan Zhang
- Graduate Program, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.,National Institute of Biological Sciences, Beijing, China
| | - Yue-He Ding
- Graduate Program, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.,National Institute of Biological Sciences, Beijing, China
| | - Sheng-Bo Fan
- Key Lab of Intelligent Information Processing of Chinese Academy of Sciences, Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Li Tao
- Graduate Program, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.,National Institute of Biological Sciences, Beijing, China
| | - Bing Yang
- National Institute of Biological Sciences, Beijing, China
| | - Xiangke Li
- National Institute of Biological Sciences, Beijing, China
| | - Shoucai Ma
- National Institute of Biological Sciences, Beijing, China
| | - Junjie Liu
- Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Boya Feng
- Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Xiaohui Liu
- National Institute of Biological Sciences, Beijing, China
| | - Hong-Wei Wang
- Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Si-Min He
- Key Lab of Intelligent Information Processing of Chinese Academy of Sciences, Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Ning Gao
- Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Keqiong Ye
- National Institute of Biological Sciences, Beijing, China
| | - Meng-Qiu Dong
- Graduate Program, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.,National Institute of Biological Sciences, Beijing, China
| | - Xiaoguang Lei
- National Institute of Biological Sciences, Beijing, China.,Synthetic and Functional Biomolecules Center, Peking University, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.,Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
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13
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Leitner A, Faini M, Stengel F, Aebersold R. Crosslinking and Mass Spectrometry: An Integrated Technology to Understand the Structure and Function of Molecular Machines. Trends Biochem Sci 2016; 41:20-32. [DOI: 10.1016/j.tibs.2015.10.008] [Citation(s) in RCA: 226] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 10/18/2015] [Accepted: 10/29/2015] [Indexed: 01/30/2023]
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14
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Liu F, Heck AJR. Interrogating the architecture of protein assemblies and protein interaction networks by cross-linking mass spectrometry. Curr Opin Struct Biol 2015; 35:100-8. [DOI: 10.1016/j.sbi.2015.10.006] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 10/14/2015] [Accepted: 10/28/2015] [Indexed: 01/28/2023]
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15
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Proteome-wide profiling of protein assemblies by cross-linking mass spectrometry. Nat Methods 2015; 12:1179-84. [PMID: 26414014 DOI: 10.1038/nmeth.3603] [Citation(s) in RCA: 329] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 08/17/2015] [Indexed: 12/18/2022]
Abstract
We describe an integrated workflow that robustly identifies cross-links from endogenous protein complexes in human cellular lysates. Our approach is based on the application of mass spectrometry (MS)-cleavable cross-linkers, sequential collision-induced dissociation (CID)-tandem MS (MS/MS) and electron-transfer dissociation (ETD)-MS/MS acquisitions, and a dedicated search engine, XlinkX, which allows rapid cross-link identification against a complete human proteome database. This approach allowed us to detect 2,179 unique cross-links (1,665 intraprotein cross-links at a 5% false discovery rate (FDR) and 514 interprotein cross-links at 1% FDR) in HeLa cell lysates. We validated the confidence of our cross-linking results by using a target-decoy strategy and mapping the observed cross-link distances onto existing high-resolution structures. Our data provided new structural information about many protein assemblies and captured dynamic interactions of the ribosome in contact with different elongation factors.
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16
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Srinivasa S, Ding X, Kast J. Formaldehyde cross-linking and structural proteomics: Bridging the gap. Methods 2015; 89:91-8. [PMID: 25979347 DOI: 10.1016/j.ymeth.2015.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Revised: 04/30/2015] [Accepted: 05/06/2015] [Indexed: 12/21/2022] Open
Abstract
Proteins are dynamic entities constantly moving and altering their structures based on their functions and interactions inside and outside the cell. Formaldehyde cross-linking combined with mass spectrometry can accurately capture interactions of these rapidly changing biomolecules while maintaining their physiological surroundings. Even with its numerous established uses in biology and compatibility with mass spectrometry, formaldehyde has not yet been applied in structural proteomics. However, formaldehyde cross-linking is moving toward analyzing tertiary structure, which conventional cross-linkers have already accomplished. The purpose of this review is to describe the potential of formaldehyde cross-linking in structural proteomics by highlighting its applications, characteristics and current status in the field.
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Affiliation(s)
- Savita Srinivasa
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Xuan Ding
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS 39762, United States
| | - Juergen Kast
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
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17
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Vaughan RC, Kao CC. Mapping protein-RNA interactions by RCAP, RNA-cross-linking and peptide fingerprinting. Methods Mol Biol 2015; 1297:225-236. [PMID: 25896007 DOI: 10.1007/978-1-4939-2562-9_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
RNA nanotechnology often feature protein RNA complexes. The interaction between proteins and large RNAs are difficult to study using traditional structure-based methods like NMR or X-ray crystallography. RCAP, an approach that uses reversible-cross-linking affinity purification method coupled with mass spectrometry, has been developed to map regions within proteins that contact RNA. This chapter details how RCAP is applied to map protein-RNA contacts within virions.
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Affiliation(s)
- Robert C Vaughan
- Department of Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne St., 201A Simon Hall, Bloomington, IN, 47405, USA,
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18
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A gas phase cleavage reaction of cross-linked peptides for protein complex topology studies by peptide fragment fingerprinting from large sequence database. J Proteomics 2014; 108:65-77. [DOI: 10.1016/j.jprot.2014.05.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/23/2014] [Accepted: 05/08/2014] [Indexed: 11/23/2022]
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19
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Koolen HHF, Gomes AF, Schwab NV, Eberlin MN, Gozzo FC. Imidate-based cross-linkers for structural proteomics: increased charge of protein and peptide ions and CID and ECD fragmentation studies. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:1181-1191. [PMID: 24781457 DOI: 10.1007/s13361-014-0900-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 03/21/2014] [Accepted: 03/21/2014] [Indexed: 06/03/2023]
Abstract
Chemical cross-linking is an attractive low-resolution technique for structural studies of protein complexes. Distance constraints obtained from cross-linked peptides identified by mass spectrometry (MS) are used to construct and validate protein models. Amidinating cross-linkers such as diethyl suberthioimidate (DEST) have been used successfully in chemical cross-linking experiments. In this work, the application of a commercial diimidate cross-linking reagent, dimethyl suberimidate (DMS), was evaluated with model peptides and proteins. The peptides were designed with acetylated N-termini followed by random sequences containing two Lys residues separated by an Arg residue. After cross-linking reactions, intra- and intermolecular cross-linked species were submitted to CID and ECD dissociations to study their fragmentation features in the gas phase. Fragmentation of intramolecular peptides by collision induced dissociation (CID) demonstrates a unique two-step fragmentation pathway involving formation of a ketimine as intermediate. Electron capture and electron transfer dissociation (ECD and ETD) experiments demonstrated that the cyclic moiety is not dissociated. Intermolecular species demonstrated previously described fragmentation behavior in both CID and ECD experiments. The charge state distributions (CSD) obtained after reaction with DMS were compared with those obtained with disuccinimidyl suberate (DSS). CSDs for peptides and proteins were increased after their reaction with DMS, owing to the higher basicity of DMS modified species. These features were also observed in LC-MS experiments with bovine carbonic anhydrase II (BCA) after cross-linking with DMS and tryptic proteolysis. Cross-linked peptides derived from this protein were identified at high confidence and those species were in agreement with the crystal structure of BCA.
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Affiliation(s)
- Hector H F Koolen
- Institute of Chemistry, University of Campinas and Instituto Nacional de Ciência e Tecnologia de Bioanalítica, Sao Paulo, 13083-970, Brazil
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20
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Chemical cross-linking/mass spectrometry targeting acidic residues in proteins and protein complexes. Proc Natl Acad Sci U S A 2014; 111:9455-60. [PMID: 24938783 DOI: 10.1073/pnas.1320298111] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The study of proteins and protein complexes using chemical cross-linking followed by the MS identification of the cross-linked peptides has found increasingly widespread use in recent years. Thus far, such analyses have used almost exclusively homobifunctional, amine-reactive cross-linking reagents. Here we report the development and application of an orthogonal cross-linking chemistry specific for carboxyl groups. Chemical cross-linking of acidic residues is achieved using homobifunctional dihydrazides as cross-linking reagents and a coupling chemistry at neutral pH that is compatible with the structural integrity of most protein complexes. In addition to cross-links formed through insertion of the dihydrazides with different spacer lengths, zero-length cross-link products are also obtained, thereby providing additional structural information. We demonstrate the application of the reaction and the MS identification of the resulting cross-linked peptides for the chaperonin TRiC/CCT and the 26S proteasome. The results indicate that the targeting of acidic residues for cross-linking provides distance restraints that are complementary and orthogonal to those obtained from lysine cross-linking, thereby expanding the yield of structural information that can be obtained from cross-linking studies and used in hybrid modeling approaches.
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21
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Wang J, Anania VG, Knott J, Rush J, Lill JR, Bourne PE, Bandeira N. Combinatorial approach for large-scale identification of linked peptides from tandem mass spectrometry spectra. Mol Cell Proteomics 2014; 13:1128-36. [PMID: 24493012 DOI: 10.1074/mcp.m113.035758] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The combination of chemical cross-linking and mass spectrometry has recently been shown to constitute a powerful tool for studying protein-protein interactions and elucidating the structure of large protein complexes. However, computational methods for interpreting the complex MS/MS spectra from linked peptides are still in their infancy, making the high-throughput application of this approach largely impractical. Because of the lack of large annotated datasets, most current approaches do not capture the specific fragmentation patterns of linked peptides and therefore are not optimal for the identification of cross-linked peptides. Here we propose a generic approach to address this problem and demonstrate it using disulfide-bridged peptide libraries to (i) efficiently generate large mass spectral reference data for linked peptides at a low cost and (ii) automatically train an algorithm that can efficiently and accurately identify linked peptides from MS/MS spectra. We show that using this approach we were able to identify thousands of MS/MS spectra from disulfide-bridged peptides through comparison with proteome-scale sequence databases and significantly improve the sensitivity of cross-linked peptide identification. This allowed us to identify 60% more direct pairwise interactions between the protein subunits in the 20S proteasome complex than existing tools on cross-linking studies of the proteasome complexes. The basic framework of this approach and the MS/MS reference dataset generated should be valuable resources for the future development of new tools for the identification of linked peptides.
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Affiliation(s)
- Jian Wang
- Bioinformatics Program, University of California, San Diego, La Jolla, California
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22
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Lysine-specific chemical cross-linking of protein complexes and identification of cross-linking sites using LC-MS/MS and the xQuest/xProphet software pipeline. Nat Protoc 2013; 9:120-37. [DOI: 10.1038/nprot.2013.168] [Citation(s) in RCA: 200] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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23
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Konermann L, Vahidi S, Sowole MA. Mass Spectrometry Methods for Studying Structure and Dynamics of Biological Macromolecules. Anal Chem 2013; 86:213-32. [DOI: 10.1021/ac4039306] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario, N6A 5B7 Canada
| | - Siavash Vahidi
- Department of Chemistry, The University of Western Ontario, London, Ontario, N6A 5B7 Canada
| | - Modupeola A. Sowole
- Department of Chemistry, The University of Western Ontario, London, Ontario, N6A 5B7 Canada
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24
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Merkley ED, Cort JR, Adkins JN. Cross-linking and mass spectrometry methodologies to facilitate structural biology: finding a path through the maze. ACTA ACUST UNITED AC 2013; 14:77-90. [PMID: 23917845 DOI: 10.1007/s10969-013-9160-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 07/26/2013] [Indexed: 12/12/2022]
Abstract
Multiprotein complexes, rather than individual proteins, make up a large part of the biological macromolecular machinery of a cell. Understanding the structure and organization of these complexes is critical to understanding cellular function. Chemical cross-linking coupled with mass spectrometry is emerging as a complementary technique to traditional structural biology methods and can provide low-resolution structural information for a multitude of purposes, such as distance constraints in computational modeling of protein complexes. In this review, we discuss the experimental considerations for successful application of chemical cross-linking-mass spectrometry in biological studies and highlight three examples of such studies from the recent literature. These examples (as well as many others) illustrate the utility of a chemical cross-linking-mass spectrometry approach in facilitating structural analysis of large and challenging complexes.
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Affiliation(s)
- Eric D Merkley
- MS K8-98, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
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25
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O'Brien JP, Pruet JM, Brodbelt JS. Chromogenic chemical probe for protein structural characterization via ultraviolet photodissociation mass spectrometry. Anal Chem 2013; 85:7391-7. [PMID: 23855605 DOI: 10.1021/ac401305f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A chemical probe/ultraviolet photodissociation (UVPD) mass spectrometry strategy for evaluating structures of proteins and protein complexes is reported, as demonstrated for lysozyme and beta-lactoglobulin with and without bound ligands. The chemical probe, NN, incorporates a UV chromophore that endows peptides with high cross sections at 351 nm, a wavelength not absorbed by unmodified peptides. Thus, NN-modified peptides can readily be differentiated from nonmodified peptides in complex tryptic digests created upon proteolysis of proteins after their exposure to the NN chemical probe. The NN chemical probe also affords two diagnostic reporter ions detected upon UVPD of the NN-modified peptide that provides a facile method for the identification of NN peptides within complex mixtures. Quantitation of the modified and unmodified peptides allows estimation of the surface accessibilities of lysine residues based on their relative reactivities with the NN chemical probe.
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Affiliation(s)
- John P O'Brien
- Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, TX 78712, United States
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26
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Chavez JD, Weisbrod CR, Zheng C, Eng JK, Bruce JE. Protein interactions, post-translational modifications and topologies in human cells. Mol Cell Proteomics 2013; 12:1451-67. [PMID: 23354917 PMCID: PMC3650351 DOI: 10.1074/mcp.m112.024497] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 12/12/2012] [Indexed: 12/22/2022] Open
Abstract
The unique and remarkable physicochemical properties of protein surface topologies give rise to highly specific biomolecular interactions, which form the framework through which living systems are able to carry out their vast array of functions. Technological limitations undermine efforts to probe protein structures and interactions within unperturbed living systems on a large scale. Rapid chemical stabilization of proteins and protein complexes through chemical cross-linking offers the alluring possibility to study details of the protein structure to function relationships as they exist within living cells. Here we apply the latest technological advances in chemical cross-linking combined with mass spectrometry to study protein topologies and interactions from living human cells identifying a total of 368 cross-links. These include cross-links from all major cellular compartments including membrane, cytosolic and nuclear proteins. Intraprotein and interprotein cross-links were also observed for core histone proteins, including several cross-links containing post-translational modifications which are known histone marks conferring distinct epigenetic functions. Excitingly, these results demonstrate the applicability of cross-linking to make direct topological measurements on post-translationally modified proteins. The results presented here provide new details on the structures of known multi-protein complexes as well as evidence for new protein-protein interactions.
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Affiliation(s)
- Juan D. Chavez
- From the ‡Department of Genome Science, University of Washington, Seattle, Washington 98109
| | - Chad R. Weisbrod
- From the ‡Department of Genome Science, University of Washington, Seattle, Washington 98109
| | - Chunxiang Zheng
- From the ‡Department of Genome Science, University of Washington, Seattle, Washington 98109
| | - Jimmy K. Eng
- From the ‡Department of Genome Science, University of Washington, Seattle, Washington 98109
| | - James E. Bruce
- From the ‡Department of Genome Science, University of Washington, Seattle, Washington 98109
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27
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Walzthoeni T, Leitner A, Stengel F, Aebersold R. Mass spectrometry supported determination of protein complex structure. Curr Opin Struct Biol 2013; 23:252-60. [PMID: 23522702 DOI: 10.1016/j.sbi.2013.02.008] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/17/2013] [Accepted: 02/26/2013] [Indexed: 12/23/2022]
Abstract
Virtually all the biological processes are controlled and catalyzed by proteins which are, in many cases, in complexes with other proteins. Therefore, understanding the architecture and structure of protein complexes is critical to understanding their biological role and function. Traditionally, high-resolution data for structural analysis of proteins or protein complexes have been generated by the powerful methods of X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy. More recently, mass spectrometry (MS)-based methods have been developed that provide low-resolution structural information, which contributes to the determination of the native structure of protein complexes that have remained refractory to the high-resolution methods. Native MS and affinity purification coupled with MS (AP-MS) have been used to characterize the composition, stoichiometry and connectivity of protein complexes. Chemical cross-linking MS (CX-MS) provides protein-protein interaction data supplemented with distance information that indicates residues that are in close spatial proximity in the native protein structure. Hydrogen-deuterium exchange combined with MS has been used to map protein-protein binding sites. Here, we focus on recent developments in CX-MS and native MS and their application to challenging problems in structural biology.
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Affiliation(s)
- Thomas Walzthoeni
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Wolfgang-Pauli-Str. 16, 8093 Zurich, Switzerland
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28
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Lauber MA, Rappsilber J, Reilly JP. Dynamics of ribosomal protein S1 on a bacterial ribosome with cross-linking and mass spectrometry. Mol Cell Proteomics 2012; 11:1965-76. [PMID: 23033476 PMCID: PMC3518124 DOI: 10.1074/mcp.m112.019562] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 09/19/2012] [Indexed: 11/23/2022] Open
Abstract
Ribosomal protein S1 has been shown to be a significant effector of prokaryotic translation. The protein is in fact capable of efficiently initiating translation, regardless of the presence of a Shine-Dalgarno sequence in mRNA. Structural insights into this process have remained elusive, as S1 is recalcitrant to traditional techniques of structural analysis, such as x-ray crystallography. Through the application of protein cross-linking and high resolution mass spectrometry, we have detailed the ribosomal binding site of S1 and have observed evidence of its dynamics. Our results support a previous hypothesis that S1 acts as the mRNA catching arm of the prokaryotic ribosome. We also demonstrate that in solution the major domains of the 30S subunit are remarkably flexible, capable of moving 30-50Å with respect to one another.
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Affiliation(s)
- Matthew A. Lauber
- From the ‡Department of Chemistry, Indiana University, Bloomington, Indiana 47405
| | - Juri Rappsilber
- §Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, The University of Edinburgh, Edinburgh EH9 3JR, UK and Institut für Biotechnologie, Technische Universität Berlin, 13353 Berlin, Germany
| | - James P. Reilly
- From the ‡Department of Chemistry, Indiana University, Bloomington, Indiana 47405
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29
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Jaffee EG, Lauber MA, Running WE, Reilly JP. In Vitro and In Vivo Chemical Labeling of Ribosomal Proteins: A Quantitative Comparison. Anal Chem 2012; 84:9355-61. [DOI: 10.1021/ac302115m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ethan G. Jaffee
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7000,
United States
| | - Matthew A. Lauber
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7000,
United States
| | - William E. Running
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7000,
United States
| | - James P. Reilly
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7000,
United States
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30
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He Y, Lauber MA, Reilly JP. Unique fragmentation of singly charged DEST cross-linked peptides. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:1046-1052. [PMID: 22460622 DOI: 10.1007/s13361-012-0372-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 03/03/2012] [Accepted: 03/08/2012] [Indexed: 05/31/2023]
Abstract
It has previously been shown that when cross-linking reagent diethyl suberthioimidate (DEST) reacts with primary amines of proteins to yield amidinated residues, the primary amines retain their high basicity, and cross-linked species can be enriched by strong cation exchange. It is now demonstrated that collisional activation of singly-charged DEST cross-linked peptide ions leads to preferential cleavage at the cross-linked sites. The resulting product ions facilitate the detection and identification of cross-linked peptides.
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Affiliation(s)
- Yi He
- Indiana University, Bloomington, IN, USA
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31
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Klockenbusch C, O'Hara JE, Kast J. Advancing formaldehyde cross-linking towards quantitative proteomic applications. Anal Bioanal Chem 2012; 404:1057-67. [PMID: 22610548 DOI: 10.1007/s00216-012-6065-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/18/2012] [Accepted: 04/19/2012] [Indexed: 10/28/2022]
Abstract
Formaldehyde is a key fixation reagent. This review explores its application in combination with qualitative and quantitative mass spectrometry (MS). Formalin-fixed and paraffin-embedded (FFPE) tissues form a large reservoir of biologically valuable samples and their investigation by MS has only recently started. Furthermore, formaldehyde can be used to stabilise protein-protein interactions in living cells. Because formaldehyde is able to modify proteins, performing MS analysis on these samples can pose a challenge. Here we discuss the chemistry of formaldehyde cross-linking, describe the problems of and progress in these two applications and their common aspects, and evaluate the potential of these methods for the future.
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Affiliation(s)
- Cordula Klockenbusch
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
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32
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Leitner A, Joachimiak LA, Bracher A, Mönkemeyer L, Walzthoeni T, Chen B, Pechmann S, Holmes S, Cong Y, Ma B, Ludtke S, Chiu W, Hartl FU, Aebersold R, Frydman J. The molecular architecture of the eukaryotic chaperonin TRiC/CCT. Structure 2012; 20:814-25. [PMID: 22503819 PMCID: PMC3350567 DOI: 10.1016/j.str.2012.03.007] [Citation(s) in RCA: 230] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 03/22/2012] [Accepted: 03/23/2012] [Indexed: 01/27/2023]
Abstract
TRiC/CCT is a highly conserved and essential chaperonin that uses ATP cycling to facilitate folding of approximately 10% of the eukaryotic proteome. This 1 MDa hetero-oligomeric complex consists of two stacked rings of eight paralogous subunits each. Previously proposed TRiC models differ substantially in their subunit arrangements and ring register. Here, we integrate chemical crosslinking, mass spectrometry, and combinatorial modeling to reveal the definitive subunit arrangement of TRiC. In vivo disulfide mapping provided additional validation for the crosslinking-derived arrangement as the definitive TRiC topology. This subunit arrangement allowed the refinement of a structural model using existing X-ray diffraction data. The structure described here explains all available crosslink experiments, provides a rationale for previously unexplained structural features, and reveals a surprising asymmetry of charges within the chaperonin folding chamber.
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Affiliation(s)
- Alexander Leitner
- Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | | | - Andreas Bracher
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Leonie Mönkemeyer
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Thomas Walzthoeni
- Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
- Ph.D. Program in Molecular Life Sciences, University of Zurich/ETH Zurich 8057 Zurich, Switzerland
| | - Bryan Chen
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | | | - Susan Holmes
- Department of Statistics, Stanford University, Stanford, CA 94305, USA
| | - Yao Cong
- National Center for Macromolecular Imaging; Verna and Marrs McLean Department of Biochemistry and Molecular Biology Baylor College of Medicine, Houston, TX 77030, USA
| | - Boxue Ma
- National Center for Macromolecular Imaging; Verna and Marrs McLean Department of Biochemistry and Molecular Biology Baylor College of Medicine, Houston, TX 77030, USA
| | - Steve Ludtke
- National Center for Macromolecular Imaging; Verna and Marrs McLean Department of Biochemistry and Molecular Biology Baylor College of Medicine, Houston, TX 77030, USA
| | - Wah Chiu
- National Center for Macromolecular Imaging; Verna and Marrs McLean Department of Biochemistry and Molecular Biology Baylor College of Medicine, Houston, TX 77030, USA
| | - F. Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Ruedi Aebersold
- Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
- Faculty of Science, University of Zurich, Zurich, Switzerland
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, CA 94305, USA
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33
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Buncherd H, Nessen MA, Nouse N, Stelder SK, Roseboom W, Dekker HL, Arents JC, Smeenk LE, Wanner MJ, van Maarseveen JH, Yang X, Lewis PJ, de Koning LJ, de Koster CG, de Jong L. Selective enrichment and identification of cross-linked peptides to study 3-D structures of protein complexes by mass spectrometry. J Proteomics 2012; 75:2205-15. [DOI: 10.1016/j.jprot.2012.01.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 01/12/2012] [Accepted: 01/20/2012] [Indexed: 10/14/2022]
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34
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Fritzsche R, Ihling CH, Götze M, Sinz A. Optimizing the enrichment of cross-linked products for mass spectrometric protein analysis. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2012; 26:653-8. [PMID: 22328219 DOI: 10.1002/rcm.6150] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
RATIONALE Chemical cross-linking in combination with a mass spectrometric analysis of the created cross-linked products is an area of growing interest for deriving low-resolution structural information of proteins and protein complexes. One of the greatest challenges is the complexity of the created cross-linking mixtures, which can be met by a charge-based enrichment of cross-linked peptides after proteolytic digestion using strong cation-exchange (SCX) chromatography. METHODS SCX chromatography was used for the enrichment of cross-linked peptides with the N-hydroxysuccinimide ester bis(sulfosuccinimidyl)succinate (BS(3)) prior to a mass spectrometric analysis by nano-HPLC/nano-ESI-LTQ-Orbitrap-MS/MS. Bovine serum albumin (BSA) and glutathione S-transferase (GST) were employed as model proteins. RESULTS Conditions for SCX enrichment were optimized for obtaining as many interpeptide cross-linked peptides as possible in order to maximize the amount of structural information from a single experiment. With an SCX-based enrichment step of cross-linked products within BSA using the cross-linker BS(3), 154 interpeptidal cross-linking products were identified during nano-HPLC/nano-ESI-MS/MS analyses, whereas analyses without a prior SCX enrichment allowed the identification of merely 20 cross-linked products. The application of the SCX enrichment strategy for the analysis of cross-linked products of GST with BS(3) allowed the identification of 26 interpeptidal cross-linked products compared with 16 without SCX enrichment. CONCLUSIONS For both proteins investigated herein, BSA and GST, the introduction of an SCX-based enrichment step prior to nano-HPLC/nano-ESI-MS/MS of cross-linked products led to a considerable gain in structural information.
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Affiliation(s)
- Romy Fritzsche
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Martin-Luther University Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, D-06120, Halle (Saale), Germany
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Leitner A, Reischl R, Walzthoeni T, Herzog F, Bohn S, Förster F, Aebersold R. Expanding the chemical cross-linking toolbox by the use of multiple proteases and enrichment by size exclusion chromatography. Mol Cell Proteomics 2012; 11:M111.014126. [PMID: 22286754 PMCID: PMC3316732 DOI: 10.1074/mcp.m111.014126] [Citation(s) in RCA: 225] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chemical cross-linking in combination with mass spectrometric analysis offers the potential to obtain low-resolution structural information from proteins and protein complexes. Identification of peptides connected by a cross-link provides direct evidence for the physical interaction of amino acid side chains, information that can be used for computational modeling purposes. Despite impressive advances that were made in recent years, the number of experimentally observed cross-links still falls below the number of possible contacts of cross-linkable side chains within the span of the cross-linker. Here, we propose two complementary experimental strategies to expand cross-linking data sets. First, enrichment of cross-linked peptides by size exclusion chromatography selects cross-linked peptides based on their higher molecular mass, thereby depleting the majority of unmodified peptides present in proteolytic digests of cross-linked samples. Second, we demonstrate that the use of proteases in addition to trypsin, such as Asp-N, can additionally boost the number of observable cross-linking sites. The benefits of both SEC enrichment and multiprotease digests are demonstrated on a set of model proteins and the improved workflow is applied to the characterization of the 20S proteasome from rabbit and Schizosaccharomyces pombe.
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Affiliation(s)
- Alexander Leitner
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule Zurich, Wolfgang-Pauli-Strasse 16, 8093 Zurich, Switzerland
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Chang FMJ, Lauber MA, Running WE, Reilly JP, Giedroc DP. Ratiometric pulse-chase amidination mass spectrometry as a probe of biomolecular complex formation. Anal Chem 2011; 83:9092-9. [PMID: 22007758 DOI: 10.1021/ac202154r] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Selective chemical modification of protein side chains coupled with mass spectrometry is often most informative when used to compare residue-specific reactivities in a number of functional states or macromolecular complexes. Herein, we develop ratiometric pulse-chase amidination mass spectrometry (rPAm-MS) as a site-specific probe of lysine reactivities at equilibrium using the Cu(I)-sensing repressor CsoR from Bacillus subtilis as a model system. CsoR in various allosteric states was reacted with S-methyl thioacetimidate (SMTA) for pulse time, t, and chased with excess of S-methyl thiopropionimidate (SMTP) (Δ = 14 amu), quenched and digested with chymotrypsin or Glu-C protease, and peptides were quantified by high-resolution matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and/or liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). We show that the reactivities of individual lysines from peptides containing up to three Lys residues are readily quantified using this method. New insights into operator DNA binding and the Cu(I)-mediated structural transition in the tetrameric copper sensor CsoR are also obtained.
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Affiliation(s)
- Feng-Ming James Chang
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405-7102, USA
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