1
|
Zheng X, Zhu H, Zhao X, Wang J, Li Q, Zhao X. Emerging affinity methods for protein-drug interaction analysis. J Pharm Biomed Anal 2024; 249:116371. [PMID: 39047466 DOI: 10.1016/j.jpba.2024.116371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/15/2024] [Accepted: 07/15/2024] [Indexed: 07/27/2024]
Abstract
The study of protein-drug interaction plays a crucial role in understanding drug mechanisms, identifying new drug targets and biomarkers, and facilitating drug development and disease treatment. In recent years, significant progress has been made in various protein-drug interaction research methods due to the rapid development and in-depth application of mass spectrometry, nuclear magnetic resonance, Raman spectroscopy, and other technologies. The progress has enhanced the sensitivity, precision, accuracy, and applicability of analytical methods, enabling the establishment of drug-protein interaction networks. This review discusses various emerging research methods, such as native mass spectrometry, infrared spectroscopy, nuclear magnetic resonance and spectrum, biosensor technologies employing surface enhanced Raman, electrochemistry, and magneto resistive signals, as well as affinity magnetic levitation and affinity chromatography. The article also delves into the principles, applications, advantages, and limitations of these technologies.
Collapse
Affiliation(s)
- Xinxin Zheng
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China
| | - Huiting Zhu
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China
| | - Xue Zhao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China
| | - Jing Wang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China
| | - Qian Li
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China
| | - Xinfeng Zhao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China.
| |
Collapse
|
2
|
Sternicki LM, Poulsen SA. Fragment-based drug discovery campaigns guided by native mass spectrometry. RSC Med Chem 2024; 15:2270-2285. [PMID: 39026646 PMCID: PMC11253872 DOI: 10.1039/d4md00273c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 05/19/2024] [Indexed: 07/20/2024] Open
Abstract
Native mass spectrometry (nMS) is well established as a biophysical technique for characterising biomolecules and their interactions with endogenous or investigational small molecule ligands. The high sensitivity mass measurements make nMS particularly well suited for applications in fragment-based drug discovery (FBDD) screening campaigns where the detection of weakly binding ligands to a target biomolecule is crucial. We first reviewed the contributions of nMS to guiding FBDD hit identification in 2013, providing a comprehensive perspective on the early adoption of nMS for fragment screening. Here we update this initial progress with a focus on contributions of nMS that have guided FBDD for the period 2014 until end of 2023. We highlight the development of nMS adoption in FBDD in the context of other biophysical fragment screening techniques. We also discuss the roadmap for increased adoption of nMS for fragment screening beyond soluble proteins, including for guiding the discovery of fragments supporting advances in PROTAC discovery, RNA-binding small molecules and covalent therapeutic drug discovery.
Collapse
Affiliation(s)
- Louise M Sternicki
- Griffith Institute for Drug Discovery, Griffith University Nathan Brisbane Queensland 4111 Australia
- ARC Centre for Fragment-Based Design Australia
| | - Sally-Ann Poulsen
- Griffith Institute for Drug Discovery, Griffith University Nathan Brisbane Queensland 4111 Australia
- ARC Centre for Fragment-Based Design Australia
| |
Collapse
|
3
|
Quinn RJ, Mak T, Littler DR, Rossjohn J, Liu M. Discovery of Anti-SARS-CoV-2 Nsp9 Binders from Natural Products by a Native Mass Spectrometry Approach. JOURNAL OF NATURAL PRODUCTS 2023; 86:2630-2637. [PMID: 37993134 DOI: 10.1021/acs.jnatprod.3c00636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
The search for effective antiviral agents against SARS-CoV-2 remains a critical global endeavor. In this study, we focused on the viral nucleocapsid protein Nsp9, which is a key player in viral RNA replication and an attractive drug target. Employing a two-pronged approach, an in-house natural product library was screened using native mass spectrometry to identify compounds capable of binding to Nsp9. From the initial screening, apart from the previously reported hit oridonin (protein binding ratio of 0.56 in the initial screening, Kd = 7.2 ± 1.0 μM), we have identified a second Nsp9-interacting compound, the diterpenoid ryanodine, with a protein binding ratio of 0.3 and a Kd of 48.05 ± 5.03 μM. To gain deeper insights into the binding interactions and to explore potential structural requirements, the collision-induced affinity selection mass spectrometry (CIAS-MS) approach allowed us to identify six known oridonin analogues produced by the plant Rabdosia rubescens, each with varying affinities to Nsp9. Native MS validation of their individual binding activities to Nsp9 revealed that all analogues exhibited reduced affinity compared to oridonin. Structural-activity relationship analysis highlighted key functional groups, including 1-OH, 6-OH, 7-OH, and the enone moiety, which are crucial for Nsp9 binding. Combined data from our native mass spectrometry and CIAS-MS approaches provide valuable insights into the molecular interactions between Nsp9 and these compounds.
Collapse
Affiliation(s)
- Ronald J Quinn
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD 4111, Australia
| | - Tin Mak
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD 4111, Australia
| | - Dene R Littler
- Infection and Immunity Program & Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program & Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
- Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Miaomiao Liu
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, QLD 4111, Australia
| |
Collapse
|
4
|
Bennett JL, Nguyen GTH, Donald WA. Protein-Small Molecule Interactions in Native Mass Spectrometry. Chem Rev 2021; 122:7327-7385. [PMID: 34449207 DOI: 10.1021/acs.chemrev.1c00293] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Small molecule drug discovery has been propelled by the continual development of novel scientific methodologies to occasion therapeutic advances. Although established biophysical methods can be used to obtain information regarding the molecular mechanisms underlying drug action, these approaches are often inefficient, low throughput, and ineffective in the analysis of heterogeneous systems including dynamic oligomeric assemblies and proteins that have undergone extensive post-translational modification. Native mass spectrometry can be used to probe protein-small molecule interactions with unprecedented speed and sensitivity, providing unique insights into polydisperse biomolecular systems that are commonly encountered during the drug discovery process. In this review, we describe potential and proven applications of native MS in the study of interactions between small, drug-like molecules and proteins, including large multiprotein complexes and membrane proteins. Approaches to quantify the thermodynamic and kinetic properties of ligand binding are discussed, alongside a summary of gas-phase ion activation techniques that have been used to interrogate the structure of protein-small molecule complexes. We additionally highlight some of the key areas in modern drug design for which native mass spectrometry has elicited significant advances. Future developments and applications of native mass spectrometry in drug discovery workflows are identified, including potential pathways toward studying protein-small molecule interactions on a whole-proteome scale.
Collapse
Affiliation(s)
- Jack L Bennett
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Giang T H Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| |
Collapse
|
5
|
Liu XR, Zhang MM, Gross ML. Mass Spectrometry-Based Protein Footprinting for Higher-Order Structure Analysis: Fundamentals and Applications. Chem Rev 2020; 120:4355-4454. [PMID: 32319757 PMCID: PMC7531764 DOI: 10.1021/acs.chemrev.9b00815] [Citation(s) in RCA: 130] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Proteins adopt different higher-order structures (HOS) to enable their unique biological functions. Understanding the complexities of protein higher-order structures and dynamics requires integrated approaches, where mass spectrometry (MS) is now positioned to play a key role. One of those approaches is protein footprinting. Although the initial demonstration of footprinting was for the HOS determination of protein/nucleic acid binding, the concept was later adapted to MS-based protein HOS analysis, through which different covalent labeling approaches "mark" the solvent accessible surface area (SASA) of proteins to reflect protein HOS. Hydrogen-deuterium exchange (HDX), where deuterium in D2O replaces hydrogen of the backbone amides, is the most common example of footprinting. Its advantage is that the footprint reflects SASA and hydrogen bonding, whereas one drawback is the labeling is reversible. Another example of footprinting is slow irreversible labeling of functional groups on amino acid side chains by targeted reagents with high specificity, probing structural changes at selected sites. A third footprinting approach is by reactions with fast, irreversible labeling species that are highly reactive and footprint broadly several amino acid residue side chains on the time scale of submilliseconds. All of these covalent labeling approaches combine to constitute a problem-solving toolbox that enables mass spectrometry as a valuable tool for HOS elucidation. As there has been a growing need for MS-based protein footprinting in both academia and industry owing to its high throughput capability, prompt availability, and high spatial resolution, we present a summary of the history, descriptions, principles, mechanisms, and applications of these covalent labeling approaches. Moreover, their applications are highlighted according to the biological questions they can answer. This review is intended as a tutorial for MS-based protein HOS elucidation and as a reference for investigators seeking a MS-based tool to address structural questions in protein science.
Collapse
Affiliation(s)
| | | | - Michael L. Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA, 63130
| |
Collapse
|
6
|
Lyon YA, Collier MP, Riggs DL, Degiacomi MT, Benesch JLP, Julian RR. Structural and functional consequences of age-related isomerization in α-crystallins. J Biol Chem 2019; 294:7546-7555. [PMID: 30804217 PMCID: PMC6514633 DOI: 10.1074/jbc.ra118.007052] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/15/2019] [Indexed: 12/31/2022] Open
Abstract
Long-lived proteins are subject to spontaneous degradation and may accumulate a range of modifications over time, including subtle alterations such as side-chain isomerization. Recently, tandem MS has enabled identification and characterization of such peptide isomers, including those differing only in chirality. However, the structural and functional consequences of these perturbations remain largely unexplored. Here, we examined the impact of isomerization of aspartic acid or epimerization of serine at four sites mapping to crucial oligomeric interfaces in human αA- and αB-crystallin, the most abundant chaperone proteins in the eye lens. To characterize the effect of isomerization on quaternary assembly, we utilized synthetic peptide mimics, enzyme assays, molecular dynamics calculations, and native MS experiments. The oligomerization of recombinant forms of αA- and αB-crystallin that mimic isomerized residues deviated from native behavior in all cases. Isomerization also perturbs recognition of peptide substrates, either enhancing or inhibiting kinase activity. Specifically, epimerization of serine (αASer-162) dramatically weakened inter-subunit binding. Furthermore, phosphorylation of αBSer-59, known to play an important regulatory role in oligomerization, was severely inhibited by serine epimerization and altered by isomerization of nearby αBAsp-62. Similarly, isomerization of αBAsp-109 disrupted a vital salt bridge with αBArg-120, a contact that when broken has previously been shown to yield aberrant oligomerization and aggregation in several disease-associated variants. Our results illustrate how isomerization of amino acid residues, which may seem to be only a minor structural perturbation, can disrupt native structural interactions with profound consequences for protein assembly and activity.
Collapse
Affiliation(s)
- Yana A Lyon
- From the Department of Chemistry, University of California, Riverside, Riverside, California 92521
| | - Miranda P Collier
- the Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom, and
| | - Dylan L Riggs
- From the Department of Chemistry, University of California, Riverside, Riverside, California 92521
| | - Matteo T Degiacomi
- the Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom
| | - Justin L P Benesch
- the Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom, and
| | - Ryan R Julian
- From the Department of Chemistry, University of California, Riverside, Riverside, California 92521,
| |
Collapse
|
7
|
Gavriilidou AFM, Holding FP, Coyle JE, Zenobi R. Application of Native ESI-MS to Characterize Interactions between Compounds Derived from Fragment-Based Discovery Campaigns and Two Pharmaceutically Relevant Proteins. SLAS DISCOVERY 2018; 23:951-959. [PMID: 29852073 DOI: 10.1177/2472555218775921] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Native electrospray ionization mass spectrometry (ESI-MS) was applied to analyze the binding of compounds generated during fragment-based drug discovery (FBDD) campaigns against two functionally distinct proteins, the X-linked inhibitor of apoptosis protein (XIAP) and cyclin-dependent kinase 2 (CDK2). Compounds of different molecular weights and a wide range of binding affinities obtained from the hits to leads and lead optimization stages of FBDD campaigns were studied, and their dissociation constants (Kd) were measured by native ESI-MS. We demonstrate that native ESI-MS has the potential to be applied to the stages of an FBDD campaign downstream of primary screening for the detection and quantification of protein-ligand binding. Native ESI-MS was used to derive Kd values for compounds binding to XIAP, and the dissociation of the complex between XIAP and a peptide derived from the second mitochondria-derived activator of caspases (SMAC) protein induced by one of the test compounds was also investigated. Affinities of compounds binding to CDK2 gave Kd values in the low nanomolar to low millimolar range, and Kd values generated by MS and isothermal titration calorimetry (ITC) followed the same trend for both proteins. Practical considerations for the application of native ESI-MS are discussed in detail.
Collapse
Affiliation(s)
- Agni F M Gavriilidou
- 1 Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | | | | | - Renato Zenobi
- 1 Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| |
Collapse
|
8
|
Chingin K, Barylyuk K. Charge-State-Dependent Variation of Signal Intensity Ratio between Unbound Protein and Protein-Ligand Complex in Electrospray Ionization Mass Spectrometry: The Role of Solvent-Accessible Surface Area. Anal Chem 2018; 90:5521-5528. [PMID: 29653057 DOI: 10.1021/acs.analchem.7b05349] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Native electrospray ionization mass spectrometry (ESI-MS) is nowadays widely used for the direct and sensitive determination of protein complex stoichiometry and binding affinity constants ( Ka). A common yet poorly understood phenomenon in native ESI-MS is the difference between the charge-state distributions (CSDs) of the bound protein-ligand complex (PL) and unbound protein (P) signals. This phenomenon is typically attributed to experimental artifacts such as nonspecific binding or in-source dissociation and is considered highly undesirable, because the determined Ka values display strong variation with charge state. This situation raises serious concerns regarding the reliability of ESI-MS for the analysis of protein complexes. Here we demonstrate that, contrary to the common belief, the CSD difference between P and PL ions can occur without any loss of complex integrity, simply due to a change in the solvent-accessible surface area (ΔSASA) of the protein upon ligand binding in solution. The experimental CSD shifts for PL and P ions in ESI-MS are explained in relation to the magnitude of ΔSASA for diverse protein-ligand systems using a simple model based on the charged residue mechanism. Our analysis shows that the revealed ΔSASA factor should be considered rather general and be given attention for the correct spectral interpretation of protein complexes.
Collapse
Affiliation(s)
- Konstantin Chingin
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation , East China University of Technology , Guanglan Road 418 , Nanchang , Jiangxi , China 330013
| | - Konstantin Barylyuk
- Department of Biochemistry , University of Cambridge , Hopkins Building, Tennis Court Road , Cambridge CB2 1QW , United Kingdom
| |
Collapse
|
9
|
Yefremova Y, Danquah BD, Opuni KF, El-Kased R, Koy C, Glocker MO. Mass spectrometric characterization of protein structures and protein complexes in condensed and gas phase. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2017; 23:445-459. [PMID: 29183193 DOI: 10.1177/1469066717722256] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Proteins are essential for almost all physiological processes of life. They serve a myriad of functions which are as varied as their unique amino acid sequences and their corresponding three-dimensional structures. To fulfill their tasks, most proteins depend on stable physical associations, in the form of protein complexes that evolved between themselves and other proteins. In solution (condensed phase), proteins and/or protein complexes are in constant energy exchange with the surrounding solvent. Albeit methods to describe in-solution thermodynamic properties of proteins and of protein complexes are well established and broadly applied, they do not provide a broad enough access to life-science experimentalists to study all their proteins' properties at leisure. This leaves great desire to add novel methods to the analytical biochemist's toolbox. The development of electrospray ionization created the opportunity to characterize protein higher order structures and protein complexes rather elegantly by simultaneously lessening the need of sophisticated sample preparation steps. Electrospray mass spectrometry enabled us to translate proteins and protein complexes very efficiently into the gas phase under mild conditions, retaining both, intact protein complexes, and gross protein structures upon phase transition. Moreover, in the environment of the mass spectrometer (gas phase, in vacuo), analyte molecules are free of interactions with surrounding solvent molecules and, therefore, the energy of inter- and intramolecular forces can be studied independently from interference of the solvating environment. Provided that gas phase methods can give information which is relevant for understanding in-solution processes, gas phase protein structure studies and/or investigations on the characterization of protein complexes has rapidly gained more and more attention from the bioanalytical scientific community. Recent reports have shown that electrospray mass spectrometry provides direct access to six prime protein complex properties: stabilities, compositions, binding surfaces (epitopes), disassembly processes, stoichiometries, and thermodynamic parameters.
Collapse
Affiliation(s)
- Yelena Yefremova
- 1 Proteome Center Rostock, University of Rostock, Rostock, Germany
| | - Bright D Danquah
- 1 Proteome Center Rostock, University of Rostock, Rostock, Germany
| | | | - Reham El-Kased
- 3 Microbiology and Immunology, Faculty of Pharmacy, The British University in Egypt, Cairo, Egypt
| | - Cornelia Koy
- 1 Proteome Center Rostock, University of Rostock, Rostock, Germany
| | | |
Collapse
|
10
|
Haramija M, Peter-Katalinić J. Quantitative characterization of galectin-3-C affinity mass spectrometry measurements: Comprehensive data analysis, obstacles, shortcuts and robustness. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:1709-1719. [PMID: 28805274 DOI: 10.1002/rcm.7956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 07/14/2017] [Accepted: 08/06/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Affinity mass spectrometry (AMS) is an emerging tool in the field of the study of protein•carbohydrate complexes. However, experimental obstacles and data analysis are preventing faster integration of AMS methods into the glycoscience field. Here we show how analysis of direct electrospray ionization mass spectrometry (ESI-MS) AMS data can be simplified for screening purposes, even for complex AMS spectra. METHODS A direct ESI-MS assay was tested in this study and binding data for the galectin-3C•lactose complex were analyzed using a comprehensive and simplified data analysis approach. In the comprehensive data analysis approach, noise, all protein charge states, alkali ion adducts and signal overlap were taken into account. In a simplified approach, only the intensities of the fully protonated free protein and the protein•carbohydrate complex for the main protein charge state were taken into account. RESULTS In our study, for high intensity signals, noise was negligible, sodiated protein and sodiated complex signals cancelled each other out when calculating the Kd value, and signal overlap influenced the Kd value only to a minor extent. Influence of these parameters on low intensity signals was much higher. However, low intensity protein charge states should be avoided in quantitative AMS analyses due to poor ion statistics. CONCLUSIONS The results indicate that noise, alkali ion adducts, signal overlap, as well as low intensity protein charge states, can be neglected for preliminary experiments, as well as in screening assays. One comprehensive data analysis performed as a control should be sufficient to validate this hypothesis for other binding systems as well.
Collapse
Affiliation(s)
- Marko Haramija
- Institute of Medical Physics and Biophysics, University of Münster, Robert-Koch-Strasse 31, D-48149, Münster, Germany
| | - Jasna Peter-Katalinić
- Institute of Medical Physics and Biophysics, University of Münster, Robert-Koch-Strasse 31, D-48149, Münster, Germany
| |
Collapse
|
11
|
Root K, Wittwer Y, Barylyuk K, Anders U, Zenobi R. Insight into Signal Response of Protein Ions in Native ESI-MS from the Analysis of Model Mixtures of Covalently Linked Protein Oligomers. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:1863-1875. [PMID: 28593376 DOI: 10.1007/s13361-017-1690-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 04/12/2017] [Accepted: 04/13/2017] [Indexed: 05/28/2023]
Abstract
Native ESI-MS is increasingly used for quantitative analysis of biomolecular interactions. In such analyses, peak intensity ratios measured in mass spectra are treated as abundance ratios of the respective molecules in solution. While signal intensities of similar-size analytes, such as a protein and its complex with a small molecule, can be directly compared, significant distortions of the peak ratio due to unequal signal response of analytes impede the application of this approach for large oligomeric biomolecular complexes. We use a model system based on concatenated maltose binding protein units (MBPn, n = 1, 2, 3) to systematically study the behavior of protein mixtures in ESI-MS. The MBP concatamers differ from each other only by their mass while the chemical composition and other properties remain identical. We used native ESI-MS to analyze model mixtures of MBP oligomers, including equimolar mixtures of two proteins, as well as binary mixtures containing different fractions of the individual components. Pronounced deviation from a linear dependence of the signal intensity with concentration was observed for all binary mixtures investigated. While equimolar mixtures showed linear signal dependence at low concentrations, distinct ion suppression was observed above 20 μM. We systematically studied factors that are most often used in the literature to explain the origin of suppression effects. Implications of this effect for quantifying protein-protein binding affinity by native ESI-MS are discussed in general and demonstrated for an example of an anti-MBP antibody with its ligand, MBP. Graphical Abstract ᅟ.
Collapse
Affiliation(s)
- Katharina Root
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Yves Wittwer
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Konstantin Barylyuk
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Ulrike Anders
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
| |
Collapse
|
12
|
Niu S, Kim BC, Fierke CA, Ruotolo BT. Ion Mobility-Mass Spectrometry Reveals Evidence of Specific Complex Formation between Human Histone Deacetylase 8 and Poly-r(C)-binding Protein 1. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2017; 420:9-15. [PMID: 28983190 PMCID: PMC5624731 DOI: 10.1016/j.ijms.2016.12.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Histone deacetylase 8, part of a broad class of proteins responsible for regulating transcription and many other cellular processes and directly linked to a host of human disease through its mis-function, has been canonically described as a zinc-based mettalo-enzyme for many years. Recent evidence, however, has linked this protein to iron incorporation, loaded through transient interactions with the poly r(C)-binding protein 1, a metallo-chaperone and storage protein. In this report, we construct and deploy an electrospray-mass spectrometry based assay aimed at quantifying the interaction strength between these two weakly-associated proteins, as well as the zinc and iron associated form of the histone deacetylase. Despite challenges derived from artifact protein complexes derived from the electrospray process, we use carefully-constructed positive and negative control experiments, along with detailed measurements of protein ionization efficiency to validate our dissociation constant measurements for protein dimers in this size range. Furthermore, our data strongly support that complexes between histone deacetylase 8 and poly r(C)-binding protein 1 are specific, and that they are equally strong when both zinc and iron-loaded proteins are involved, or perhaps mildly promoted in the latter case, suggesting an in vivo role for the non-canonical, iron-incorporated histone deacetylase.
Collapse
|
13
|
Eschweiler JD, Kerr R, Rabuck-Gibbons J, Ruotolo BT. Sizing Up Protein-Ligand Complexes: The Rise of Structural Mass Spectrometry Approaches in the Pharmaceutical Sciences. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2017; 10:25-44. [PMID: 28301749 DOI: 10.1146/annurev-anchem-061516-045414] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Capturing the dynamic interplay between proteins and their myriad interaction partners is critically important for advancing our understanding of almost every biochemical process and human disease. The importance of this general area has spawned many measurement methods capable of assaying such protein complexes, and the mass spectrometry-based structural biology methods described in this review form an important part of that analytical arsenal. Here, we survey the basic principles of such measurements, cover recent applications of the technology that have focused on protein-small-molecule complexes, and discuss the bright future awaiting this group of technologies.
Collapse
Affiliation(s)
| | - Richard Kerr
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109;
| | | | - Brandon T Ruotolo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109;
| |
Collapse
|
14
|
Jovanović M, Peter-Katalinić J. Preliminary mass spectrometry characterization studies of galectin-3 samples, prior to carbohydrate-binding studies using Affinity mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:129-136. [PMID: 27791284 DOI: 10.1002/rcm.7775] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 09/11/2016] [Accepted: 10/24/2016] [Indexed: 05/22/2023]
Abstract
RATIONALE Investigation of non-covalent complexes of proteins using Affinity Mass Spectrometry (AMS) represents a major challenge in modern biomedical research. However, many experimental obstacles can make AMS data analysis complex. Additionally, sample purity and size of the protein may still pose significant challenges. METHODS Matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) was used for initial mapping of protein samples. nanoESI (electrospray ionization) quadrupole-time-of-flight (QTOF) MS was used for mapping of protein samples under native conditions and subsequent AMS studies. The human galectin-3 protein sample was expressed in E. coli. RESULTS Full length galectin-3 was difficult to work with, due to several truncated forms observed after the purification procedures. On the other hand, galectin-3C produced excellent quality nanoESI-MS spectra. A covalent adduct of lactose was found to be located on residue Lys 176. Functional AMS control studies indicated that galectin-3 interactions with oligosaccharides may be dependent on its charge. CONCLUSIONS Mass spectrometry represents a valuable tool that can be efficiently used for structural characterization of protein samples prior to functional analyses. By means of accurate mass measurements, many protein truncations can be identified based on mass alone. Analysis of covalent adducts is more challenging. Finally, for AMS studies, careful use of controls may reveal charge-dependence of protein-oligosaccharide interactions. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Marko Jovanović
- Institute of Medical Physics and Biophysics, University of Münster, Robert-Koch-Strasse 31, D-48149, Münster, Germany
- Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51 000, Rijeka, Croatia
| | - Jasna Peter-Katalinić
- Institute of Medical Physics and Biophysics, University of Münster, Robert-Koch-Strasse 31, D-48149, Münster, Germany
| |
Collapse
|
15
|
Chingin K, Barylyuk K, Chen H. On the preservation of non-covalent protein complexes during electrospray ionization. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:rsta.2015.0377. [PMID: 27644969 PMCID: PMC5031642 DOI: 10.1098/rsta.2015.0377] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/13/2016] [Indexed: 06/06/2023]
Abstract
The application range of electrospray ionization mass spectrometry for the quantitative determination of stoichiometries and binding constants for non-covalent protein complexes is broadly discussed. The underlying fundamental question is whether or not the original molecular equilibrium can be preserved during the ionization process and be revealed by subsequent mass spectrometry analysis. Here, we take a new look at this question by discussing recent studies in droplet chemistry.This article is part of the themed issue 'Quantitative mass spectrometry'.
Collapse
Affiliation(s)
- Konstantin Chingin
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Guanglan Road 418, Nanchang, Jiangxi 330013, People's Republic of China
| | - Konstantin Barylyuk
- Department of Biochemistry, University of Cambridge, Hopkins Building, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Huanwen Chen
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Guanglan Road 418, Nanchang, Jiangxi 330013, People's Republic of China
| |
Collapse
|
16
|
Tang J, Fu Q, Cui M, Liu Z, Liu S. Investigation on the labile interactions of proteins and ligands using electrospray ionization mass spectrometry combined with a mathematical method. JOURNAL OF MASS SPECTROMETRY : JMS 2016; 51:578-582. [PMID: 28239966 DOI: 10.1002/jms.3785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 04/21/2016] [Accepted: 05/02/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Jun Tang
- Key Laboratory of Synthetic Rubber, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, China
- University of the Chinese Academy of Sciences, Beijing, 100039, China
| | - Qiang Fu
- Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, China
- University of the Chinese Academy of Sciences, Beijing, 100039, China
| | - Meng Cui
- Key Laboratory of Synthetic Rubber, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, China
- Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, China
| | - Zhiqiang Liu
- Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, China
| | - Shuying Liu
- Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, China
- Changchun University of Chinese Medicine, Changchun, 130117, China
| |
Collapse
|
17
|
Native Mass Spectrometry in Fragment-Based Drug Discovery. Molecules 2016; 21:molecules21080984. [PMID: 27483215 PMCID: PMC6274484 DOI: 10.3390/molecules21080984] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 07/14/2016] [Accepted: 07/23/2016] [Indexed: 11/17/2022] Open
Abstract
The advent of native mass spectrometry (MS) in 1990 led to the development of new mass spectrometry instrumentation and methodologies for the analysis of noncovalent protein-ligand complexes. Native MS has matured to become a fast, simple, highly sensitive and automatable technique with well-established utility for fragment-based drug discovery (FBDD). Native MS has the capability to directly detect weak ligand binding to proteins, to determine stoichiometry, relative or absolute binding affinities and specificities. Native MS can be used to delineate ligand-binding sites, to elucidate mechanisms of cooperativity and to study the thermodynamics of binding. This review highlights key attributes of native MS for FBDD campaigns.
Collapse
|
18
|
Establish an automated flow injection ESI-MS method for the screening of fragment based libraries: Application to Hsp90. Eur J Pharm Sci 2015; 76:83-94. [DOI: 10.1016/j.ejps.2015.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/30/2015] [Accepted: 05/03/2015] [Indexed: 02/06/2023]
|
19
|
Santos IC, Waybright VB, Fan H, Ramirez S, Mesquita RBR, Rangel AOSS, Fryčák P, Schug KA. Determination of Noncovalent Binding Using a Continuous Stirred Tank Reactor as a Flow Injection Device Coupled to Electrospray Ionization Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:1204-1212. [PMID: 25832030 DOI: 10.1007/s13361-015-1113-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 02/17/2015] [Accepted: 02/18/2015] [Indexed: 06/04/2023]
Abstract
Described is a new method based on the concept of controlled band dispersion, achieved by hyphenating flow injection analysis with ESI-MS for noncovalent binding determinations. A continuous stirred tank reactor (CSTR) was used as a FIA device for exponential dilution of an equimolar host-guest solution over time. The data obtained was treated for the noncovalent binding determination using an equimolar binding model. Dissociation constants between vancomycin and Ac-Lys(Ac)-Ala-Ala-OH peptide stereoisomers were determined using both the positive and negative ionization modes. The results obtained for Ac-L-Lys(Ac)-D-Ala-D-Ala (a model for a Gram-positive bacterial cell wall) binding were in reasonable agreement with literature values made by other mass spectrometry binding determination techniques. Also, the developed method allowed the determination of dissociation constants for vancomycin with Ac-L-Lys(Ac)-D-Ala-L-Ala, Ac-L-Lys(Ac)-L-Ala-D-Ala, and Ac-L-Lys(Ac)-L-Ala-L-Ala. Although some differences in measured binding affinities were noted using different ionization modes, the results of each determination were generally consistent. Differences are likely attributable to the influence of a pseudo-physiological ammonium acetate buffer solution on the formation of positively- and negatively-charged ionic complexes.
Collapse
Affiliation(s)
- Inês C Santos
- CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Universidade Católica Portuguesa/Porto, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401, Porto, Portugal
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Sharawy M, Consta S. How do non-covalent complexes dissociate in droplets? A case study of the desolvation of dsDNA from a charged aqueous nanodrop. Phys Chem Chem Phys 2015; 17:25550-62. [DOI: 10.1039/c5cp04331j] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We present the desolvation mechanism of a double-stranded oligodeoxynucleotide (dsDNA) from an aqueous nanodrop studied by using atomistic molecular dynamics methods.
Collapse
Affiliation(s)
- Mahmoud Sharawy
- Department of Chemistry
- The University of Western Ontario
- London
- Canada N6A 5B7
| | - Styliani Consta
- Department of Chemistry
- The University of Western Ontario
- London
- Canada N6A 5B7
| |
Collapse
|
21
|
Yao Y, Shams-Ud-Doha K, Daneshfar R, Kitova EN, Klassen JS. Quantifying protein-carbohydrate interactions using liquid sample desorption electrospray ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:98-106. [PMID: 25315460 DOI: 10.1007/s13361-014-1008-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 09/03/2014] [Accepted: 09/05/2014] [Indexed: 06/04/2023]
Abstract
The application of liquid sample desorption electrospray ionization mass spectrometry (liquid sample DESI-MS) for quantifying protein-carbohydrate interactions in vitro is described. Association constants for the interactions between lysozyme and β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-D-GlcNAc and β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-D-GlcNAc, and between a single chain antibody and α-D-Galp-(1 → 2)-[α-D-Abep-(1 → 3)]-α-D-Manp-OCH3 and β-D-Glcp-(1 → 2)-[α-D-Abep-(1 → 3)]-α-D-Manp-OCH3 measured using liquid sample DESI-MS were found to be in good agreement with values measured by isothermal titration calorimetry and the direct ESI-MS assay. The reference protein method, which was originally developed to correct ESI mass spectra for the occurrence of nonspecific ligand-protein binding, was shown to reliably correct liquid sample DESI mass spectra for nonspecific binding. The suitability of liquid sample DESI-MS for quantitative binding measurements carried out using solutions containing high concentrations of the nonvolatile biological buffer phosphate buffered saline (PBS) was also explored. Binding of lysozyme to β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-D-GlcNAc in aqueous solutions containing up to 1× PBS was successfully monitored using liquid sample DESI-MS; with ESI-MS the binding measurements were limited to concentrations less than 0.02 X PBS.
Collapse
Affiliation(s)
- Yuyu Yao
- Alberta Glycomics Center and Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | | | | | | | | |
Collapse
|
22
|
Cubrilovic D, Haap W, Barylyuk K, Ruf A, Badertscher M, Gubler M, Tetaz T, Joseph C, Benz J, Zenobi R. Determination of protein-ligand binding constants of a cooperatively regulated tetrameric enzyme using electrospray mass spectrometry. ACS Chem Biol 2014; 9:218-26. [PMID: 24128068 DOI: 10.1021/cb4007002] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study highlights the benefits of nano electrospray ionization mass spectrometry (nanoESI-MS) as a fast and label-free method not only for determination of dissociation constants (KD) of a cooperatively regulated enzyme but also to better understand the mechanism of enzymatic cooperativity of multimeric proteins. We present an approach to investigate the allosteric mechanism in the binding of inhibitors to the homotetrameric enzyme fructose 1,6-bisphosphatase (FBPase), a potential therapeutic target for glucose control in type 2 diabetes. A series of inhibitors binding at an allosteric site of FBPase were investigated to determine their KDs by nanoESI-MS. The KDs determined by ESI-MS correlate very well with IC50 values in solution. The Hill coefficients derived from nanoESI-MS suggest positive cooperativity. From single-point measurements we could obtain information on relative potency, stoichiometry, conformational changes, and mechanism of cooperativity. A new X-ray crystal structure of FBPase tetramer binding ligand 3 in a 4:4 stoichiometry is also reported. NanoESI-MS-based results match the current understanding of the investigated system and are in agreement with the X-ray structural data, but provide additional mechanistic insight on the ligand binding, due to the better dynamic resolution. This method offers a powerful approach for studying other proteins with allosteric binding sites, as well.
Collapse
Affiliation(s)
- Dragana Cubrilovic
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Wolfgang Haap
- F. Hoffmann-La Roche Ltd, Discovery Research, Grenzacherstr. 124, 4070 Basel, Switzerland
| | - Konstantin Barylyuk
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Armin Ruf
- F. Hoffmann-La Roche Ltd, Discovery Research, Grenzacherstr. 124, 4070 Basel, Switzerland
| | - Martin Badertscher
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Marcel Gubler
- F. Hoffmann-La Roche Ltd, Discovery Research, Grenzacherstr. 124, 4070 Basel, Switzerland
| | - Tim Tetaz
- F. Hoffmann-La Roche Ltd, Discovery Research, Grenzacherstr. 124, 4070 Basel, Switzerland
| | - Catherine Joseph
- F. Hoffmann-La Roche Ltd, Discovery Research, Grenzacherstr. 124, 4070 Basel, Switzerland
| | - Jörg Benz
- F. Hoffmann-La Roche Ltd, Discovery Research, Grenzacherstr. 124, 4070 Basel, Switzerland
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| |
Collapse
|
23
|
Lin H, Kitova EN, Klassen JS. Measuring positive cooperativity using the direct ESI-MS assay. Cholera toxin B subunit homopentamer binding to GM1 pentasaccharide. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:104-110. [PMID: 24122305 DOI: 10.1007/s13361-013-0751-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 08/12/2013] [Accepted: 08/12/2013] [Indexed: 06/02/2023]
Abstract
Direct electrospray ionization mass spectrometry (ESI-MS) assay was used to investigate the stepwise binding of the GM1 pentasaccharide β-D-Galp-(1→3)-β-D-GalpNAc-(1→4)[α-D-Neu5Ac-(2→3)]-β-D-Galp-(1→4)-β-D-Glcp (GM1os) to the cholera toxin B subunit homopentamer (CTB5) and to establish conclusively whether GM1os binding is cooperative. Apparent association constants were measured for the stepwise addition of one to five GM1os to CTB5 at pH 6.9 and 22 °C. The intrinsic association constant, which was established from the apparent association constant for the addition of a single GM1os to CTB5, was found to be (3.2 ± 0.2) × 106 M(–1). This is in reasonable agreement with the reported value of (6.4 ± 0.3) × 106 M(–1), which was measured at pH 7.4 and 25 °C using isothermal titration calorimetry (ITC). Analysis of the apparent association constants provides direct and unambiguous evidence that GM1os binding exhibits small positive cooperativity. Binding was found to be sensitive to the number of ligand-bound nearest neighbor subunits, with the affinities enhanced by a factor of 1.7 and 2.9 when binding occurs next to one or two ligand-bound subunits, respectively. These findings, which provide quantitative support for the binding model proposed by Homans and coworkers [14], highlight the unique strengths of the direct ESI-MS assay for measuring cooperative ligand binding.
Collapse
|
24
|
Barylyuk K, Gülbakan B, Xie X, Zenobi R. DNA oligonucleotides: a model system with tunable binding strength to study monomer-dimer equilibria with electrospray ionization-mass spectrometry. Anal Chem 2013; 85:11902-12. [PMID: 24274465 DOI: 10.1021/ac402669e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Electrospray ionization (ESI) is increasingly used to measure binding strengths, but it is not always clear whether the ESI process introduces artifacts. Here we propose a model monomer-dimer equilibrium system based on DNA oligonucleotides to systematically explore biomolecular self-association with the ESI-mass spectrometry (MS) titration method. The oligonucleotides are designed to be self-complementary and have the same chemical composition and mass, allowing for equal ionization probability, ion transmission, and detection efficiency in ESI-MS. The only difference is the binding strength, which is determined by the nucleotide sequence and can be tuned to cover a range of dissociation constant values. This experimental design allows one to focus on the impact of ESI on the chemical equilibrium and to avoid the other typical sources of variation in ESI-MS signal responses, which yields a direct comparison of samples with different binding strengths. For a set of seven model DNA oligonucleotides, the monomer-dimer binding equilibrium was probed with the ESI-MS titration method in both positive and negative ion modes. A mathematical model describing the dependence of the monomer-to-dimer peak intensity ratio on the DNA concentration was proposed and used to extract apparent Kd values and the fraction of DNA duplex that irreversibly dissociates in the gas phase. The Kd values determined via ESI-MS titration were compared to those determined in solution with isothermal titration calorimetry and equilibrium thermal denaturation methods and were found to be significantly lower. The observed discrepancy was attributed to a greater electrospray response of dimers relative to that of monomers.
Collapse
Affiliation(s)
- Konstantin Barylyuk
- Department of Chemistry and Applied Biosciences, ETH Zurich , Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland
| | | | | | | |
Collapse
|
25
|
Niu S, Rabuck JN, Ruotolo BT. Ion mobility-mass spectrometry of intact protein–ligand complexes for pharmaceutical drug discovery and development. Curr Opin Chem Biol 2013; 17:809-17. [DOI: 10.1016/j.cbpa.2013.06.019] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/17/2013] [Accepted: 06/18/2013] [Indexed: 11/30/2022]
|
26
|
Duffell KM, Hudson SA, McLean KJ, Munro AW, Abell C, Matak-Vinković D. Nanoelectrospray Ionization Mass Spectrometric Study of Mycobacterium tuberculosis CYP121–Ligand Interactions. Anal Chem 2013; 85:5707-14. [DOI: 10.1021/ac400236z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Katie M. Duffell
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge
CB2 1EW, United Kingdom
| | - Sean A. Hudson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge
CB2 1EW, United Kingdom
| | - Kirsty J. McLean
- Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester
M1 7DN, United Kingdom
| | - Andrew W. Munro
- Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester
M1 7DN, United Kingdom
| | - Chris Abell
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge
CB2 1EW, United Kingdom
| | - Dijana Matak-Vinković
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge
CB2 1EW, United Kingdom
| |
Collapse
|
27
|
Insights into antiamyloidogenic properties of the green tea extract (-)-epigallocatechin-3-gallate toward metal-associated amyloid-β species. Proc Natl Acad Sci U S A 2013; 110:3743-8. [PMID: 23426629 DOI: 10.1073/pnas.1220326110] [Citation(s) in RCA: 190] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Despite the significance of Alzheimer's disease, the link between metal-associated amyloid-β (metal-Aβ) and disease etiology remains unclear. To elucidate this relationship, chemical tools capable of specifically targeting and modulating metal-Aβ species are necessary, along with a fundamental understanding of their mechanism at the molecular level. Herein, we investigated and compared the interactions and reactivities of the green tea extract, (-)-epigallocatechin-3-gallate [(2R,3R)-5,7-dihydroxy-2-(3,4,5-trihydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-3-yl 3,4,5-trihydroxybenzoate; EGCG], with metal [Cu(II) and Zn(II)]-Aβ and metal-free Aβ species. We found that EGCG interacted with metal-Aβ species and formed small, unstructured Aβ aggregates more noticeably than in metal-free conditions in vitro. In addition, upon incubation with EGCG, the toxicity presented by metal-free Aβ and metal-Aβ was mitigated in living cells. To understand this reactivity at the molecular level, structural insights were obtained by ion mobility-mass spectrometry (IM-MS), 2D NMR spectroscopy, and computational methods. These studies indicated that (i) EGCG was bound to Aβ monomers and dimers, generating more compact peptide conformations than those from EGCG-untreated Aβ species; and (ii) ternary EGCG-metal-Aβ complexes were produced. Thus, we demonstrate the distinct antiamyloidogenic reactivity of EGCG toward metal-Aβ species with a structure-based mechanism.
Collapse
|
28
|
Cubrilovic D, Biela A, Sielaff F, Steinmetzer T, Klebe G, Zenobi R. Quantifying protein-ligand binding constants using electrospray ionization mass spectrometry: a systematic binding affinity study of a series of hydrophobically modified trypsin inhibitors. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:1768-77. [PMID: 22869298 DOI: 10.1007/s13361-012-0451-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 07/12/2012] [Accepted: 07/17/2012] [Indexed: 05/22/2023]
Abstract
NanoESI-MS is used for determining binding strengths of trypsin in complex with two different series of five congeneric inhibitors, whose binding affinity in solution depends on the size of the P3 substituent. The ligands of the first series contain a 4-amidinobenzylamide as P1 residue, and form a tight complex with trypsin. The inhibitors of the second series have a 2-aminomethyl-5-chloro-benzylamide as P1 group, and represent a model system for weak binders. The five different inhibitors of each group are based on the same scaffold and differ only in the length of the hydrophobic side chain of their P3 residue, which modulates the interactions in the S3/4 binding pocket of trypsin. The dissociation constants (K(D)) for high affinity ligands investigated by nanoESI-MS ranges from 15 nM to 450 nM and decreases with larger hydrophobic P3 side chains. Collision-induced dissociation (CID) experiments of five trypsin and benzamidine-based complexes show a correlation between trends in K(D) and gas-phase stability. For the second inhibitor series we could show that the effect of imidazole, a small stabilizing additive, can avoid the dissociation of the complex ions and as a result increases the relative abundance of weakly bound complexes. Here the K(D) values ranging from 2.9 to 17.6 μM, some 1-2 orders of magnitude lower than the first series. For both ligand series, the dissociation constants (K(D)) measured via nanoESI-MS were compared with kinetic inhibition constants (K(i)) in solution.
Collapse
Affiliation(s)
- Dragana Cubrilovic
- Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
| | | | | | | | | | | |
Collapse
|
29
|
El-Hawiet A, Kitova EN, Klassen JS. Quantifying Carbohydrate–Protein Interactions by Electrospray Ionization Mass Spectrometry Analysis. Biochemistry 2012; 51:4244-53. [DOI: 10.1021/bi300436x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Amr El-Hawiet
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G
2G2
| | - Elena N. Kitova
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G
2G2
| | - John S. Klassen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G
2G2
| |
Collapse
|
30
|
Jaquillard L, Saab F, Schoentgen F, Cadene M. Improved accuracy of low affinity protein-ligand equilibrium dissociation constants directly determined by electrospray ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:908-922. [PMID: 22430390 DOI: 10.1007/s13361-011-0305-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 11/07/2011] [Accepted: 11/23/2011] [Indexed: 05/31/2023]
Abstract
There is continued interest in the determination by ESI-MS of equilibrium dissociation constants (K(D)) that accurately reflect the affinity of a protein-ligand complex in solution. Issues in the measurement of K(D) are compounded in the case of low affinity complexes. Here we present a K(D) measurement method and corresponding mathematical model dealing with both gas-phase dissociation (GPD) and aggregation. To this end, a rational mathematical correction of GPD (f(sat)) is combined with the development of an experimental protocol to deal with gas-phase aggregation. A guide to apply the method to noncovalent protein-ligand systems according to their kinetic behavior is provided. The approach is validated by comparing the K(D) values determined by this method with in-solution K(D) literature values. The influence of the type of molecular interactions and instrumental setup on f(sat) is examined as a first step towards a fine dissection of factors affecting GPD. The method can be reliably applied to a wide array of low affinity systems without the need for a reference ligand or protein.
Collapse
Affiliation(s)
- Lucie Jaquillard
- Centre de Biophysique Moléculaire, CNRS UPR 4301, affiliated with Université d'Orléans, rue Charles-Sadron, 45071 Orléans, Cedex 2, France
| | | | | | | |
Collapse
|
31
|
El-Hawiet A, Kitova EN, Arutyunov D, Simpson DJ, Szymanski CM, Klassen JS. Quantifying Ligand Binding to Large Protein Complexes Using Electrospray Ionization Mass Spectrometry. Anal Chem 2012; 84:3867-70. [DOI: 10.1021/ac3005082] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amr El-Hawiet
- Alberta
Glycomics Centre and †Department of Chemistry or §Department of Biological Sciences, University of Alberta, Edmonton, Alberta,
Canada T6G 2G2
| | - Elena N. Kitova
- Alberta
Glycomics Centre and †Department of Chemistry or §Department of Biological Sciences, University of Alberta, Edmonton, Alberta,
Canada T6G 2G2
| | - Denis Arutyunov
- Alberta
Glycomics Centre and †Department of Chemistry or §Department of Biological Sciences, University of Alberta, Edmonton, Alberta,
Canada T6G 2G2
| | - David J. Simpson
- Alberta
Glycomics Centre and †Department of Chemistry or §Department of Biological Sciences, University of Alberta, Edmonton, Alberta,
Canada T6G 2G2
| | - Christine M. Szymanski
- Alberta
Glycomics Centre and †Department of Chemistry or §Department of Biological Sciences, University of Alberta, Edmonton, Alberta,
Canada T6G 2G2
| | - John S. Klassen
- Alberta
Glycomics Centre and †Department of Chemistry or §Department of Biological Sciences, University of Alberta, Edmonton, Alberta,
Canada T6G 2G2
| |
Collapse
|
32
|
Ghai R, Falconer RJ, Collins BM. Applications of isothermal titration calorimetry in pure and applied research--survey of the literature from 2010. J Mol Recognit 2012; 25:32-52. [PMID: 22213449 DOI: 10.1002/jmr.1167] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Isothermal titration calorimetry (ITC) is a biophysical technique for measuring the formation and dissociation of molecular complexes and has become an invaluable tool in many branches of science from cell biology to food chemistry. By measuring the heat absorbed or released during bond formation, ITC provides accurate, rapid, and label-free measurement of the thermodynamics of molecular interactions. In this review, we survey the recent literature reporting the use of ITC and have highlighted a number of interesting studies that provide a flavour of the diverse systems to which ITC can be applied. These include measurements of protein-protein and protein-membrane interactions required for macromolecular assembly, analysis of enzyme kinetics, experimental validation of molecular dynamics simulations, and even in manufacturing applications such as food science. Some highlights include studies of the biological complex formed by Staphylococcus aureus enterotoxin C3 and the murine T-cell receptor, the mechanism of membrane association of the Parkinson's disease-associated protein α-synuclein, and the role of non-specific tannin-protein interactions in the quality of different beverages. Recent developments in automation are overcoming limitations on throughput imposed by previous manual procedures and promise to greatly extend usefulness of ITC in the future. We also attempt to impart some practical advice for getting the most out of ITC data for those researchers less familiar with the method.
Collapse
Affiliation(s)
- Rajesh Ghai
- Institute for Molecular Bioscience (IMB), University of Queensland, St. Lucia, Queensland, 4072, Australia
| | | | | |
Collapse
|
33
|
Kitova EN, El-Hawiet A, Schnier PD, Klassen JS. Reliable determinations of protein-ligand interactions by direct ESI-MS measurements. Are we there yet? JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:431-41. [PMID: 22270873 DOI: 10.1007/s13361-011-0311-9] [Citation(s) in RCA: 188] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 11/25/2011] [Accepted: 11/29/2011] [Indexed: 05/11/2023]
Abstract
The association-dissociation of noncovalent interactions between protein and ligands, such as other proteins, carbohydrates, lipids, DNA, or small molecules, are critical events in many biological processes. The discovery and characterization of these interactions is essential to a complete understanding of biochemical reactions and pathways and to the design of novel therapeutic agents that may be used to treat a variety of diseases and infections. Over the last 20 y, electrospray ionization mass spectrometry (ESI-MS) has emerged as a versatile tool for the identification and quantification of protein-ligand interactions in vitro. Here, we describe the implementation of the direct ESI-MS assay for the determination of protein-ligand binding stoichiometry and affinity. Additionally, we outline common sources of error encountered with these measurements and various strategies to overcome them. Finally, we comment on some of the outstanding challenges associated with the implementation of the assay and highlight new areas where direct ESI-MS measurements are expected to make significant contributions in the future.
Collapse
Affiliation(s)
- Elena N Kitova
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
| | | | | | | |
Collapse
|
34
|
Boeri Erba E, Barylyuk K, Yang Y, Zenobi R. Quantifying Protein–Protein Interactions Within Noncovalent Complexes Using Electrospray Ionization Mass Spectrometry. Anal Chem 2011; 83:9251-9. [DOI: 10.1021/ac201576e] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Elisabetta Boeri Erba
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Konstantin Barylyuk
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Yang Yang
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| |
Collapse
|
35
|
Clarke DJ, Murray E, Hupp T, Mackay CL, Langridge-Smith PRR. Mapping a noncovalent protein-peptide interface by top-down FTICR mass spectrometry using electron capture dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2011; 22:1432-40. [PMID: 21953198 DOI: 10.1007/s13361-011-0155-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 04/13/2011] [Accepted: 04/15/2011] [Indexed: 05/11/2023]
Abstract
Noncovalent protein-ligand and protein-protein complexes are readily detected using electrospray ionization mass spectrometry (ESI MS). Furthermore, recent reports have demonstrated that careful use of electron capture dissociation (ECD) fragmentation allows covalent backbone bonds of protein complexes to be dissociated without disruption of noncovalent protein-ligand interactions. In this way the site of protein-ligand interfaces can be identified. To date, protein-ligand complexes, which have proven tractable to this technique, have been mediated by ionic electrostatic interactions, i.e., ion pair interactions or salt bridging. Here we extend this methodology by applying ECD to study a protein-peptide complex that contains no electrostatics interactions. We analyzed the complex between the 21 kDa p53-inhibitor protein anterior gradient-2 and its hexapeptide binding ligand (PTTIYY). ECD fragmentation of the 1:1 complex occurs with retention of protein-peptide binding and analysis of the resulting fragments allows the binding interface to be localized to a C-terminal region between residues 109 and 175. These finding are supported by a solution-phase competition assay, which implicates the region between residues 108 and 122 within AGR2 as the PTTIYY binding interface. Our study expands previous findings by demonstrating that top-down ECD mass spectrometry can be used to determine directly the sites of peptide-protein interfaces. This highlights the growing potential of using ECD and related top-down fragmentation techniques for interrogation of protein-protein interfaces.
Collapse
Affiliation(s)
- David J Clarke
- SIRCAMS, EastChem School of Chemistry, University of Edinburgh, Edinburgh, UK
| | | | | | | | | |
Collapse
|
36
|
Landreh M, Astorga-Wells J, Johansson J, Bergman T, Jörnvall H. New developments in protein structure-function analysis by MS and use of hydrogen-deuterium exchange microfluidics. FEBS J 2011; 278:3815-21. [DOI: 10.1111/j.1742-4658.2011.08215.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
37
|
Kitova EN, Soya N, Klassen JS. Identifying Specific Small-Molecule Interactions Using Electrospray Ionization Mass Spectrometry. Anal Chem 2011; 83:5160-7. [DOI: 10.1021/ac200244u] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elena N. Kitova
- Alberta Ingenuity Centre for Carbohydrate Science and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Naoto Soya
- Alberta Ingenuity Centre for Carbohydrate Science and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - John S. Klassen
- Alberta Ingenuity Centre for Carbohydrate Science and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| |
Collapse
|
38
|
Liu L, Kitova EN, Klassen JS. Quantifying protein-fatty acid interactions using electrospray ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2011; 22:310-318. [PMID: 21472590 DOI: 10.1007/s13361-010-0032-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 11/08/2010] [Indexed: 05/30/2023]
Abstract
The application of the direct electrospray ionization mass spectrometry (ESI-MS) assay to quantify interactions between bovine β-lactoglobulin (Lg) and a series of fatty acids (FA), CH(3)(CH(2))(x)COOH, where x=6 (caprylic acid, CpA), 8 (capric acid, CA), 10 (lauric acid, LA), 12 (myristic acid, MA), 14 (palmitic acid, PA) and 16 (stearic acid, SA), is described. Control ESI-MS binding measurements performed on the Lg-PA interaction revealed that both the protonated and deprotonated gas phase ions of the (Lg + PA) complex are prone to dissociate in the ion source, which leads to artificially small association constants (K (a)). The addition of imidazole, a stabilizing solution additive, at high concentration (10 mM) increased the relative abundance of (Lg + PA) complex measured by ESI-MS in both positive and negative ion modes. The K(a) value measured in negative ion mode and using sampling conditions that minimize in-source dissociation is in good agreement with a value determined using a competitive fluorescence assay. The K (a) values measured by ESI-MS for the Lg interactions with MA and SA are also consistent with values expected based on the fluorescence measurements. However, the K (a) values measured using optimal sampling conditions in positive ion mode are significantly lower than those measured in negative ion mode for all of the FAs investigated. It is concluded that the protonated gaseous ions of the (Lg + FA) complexes are kinetically less stable than the deprotonated ions. In-source dissociation was significant for the complexes of Lg with the shorter FAs (CpA, CA, and LA) in both modes and, in the case of CpA, no binding could be detected by ESI-MS. The affinities of Lg for CpA, CA, and LA determined using the reference ligand ESI-MS assay, a method for quantifying labile protein-ligand complexes that are prone to in-source dissociation, were found to be in good agreement with reported values.
Collapse
Affiliation(s)
- Lan Liu
- Alberta Ingenuity Centre for Carbohydrate Science and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | | | | |
Collapse
|
39
|
Erba EB, Zenobi R. Mass spectrometric studies of dissociation constants of noncovalent complexes. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1pc90006d] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|