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Stincone P, Naimi A, Saviola AJ, Reher R, Petras D. Decoding the molecular interplay in the central dogma: An overview of mass spectrometry-based methods to investigate protein-metabolite interactions. Proteomics 2024; 24:e2200533. [PMID: 37929699 DOI: 10.1002/pmic.202200533] [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] [Received: 07/07/2023] [Revised: 10/15/2023] [Accepted: 10/23/2023] [Indexed: 11/07/2023]
Abstract
With the emergence of next-generation nucleotide sequencing and mass spectrometry-based proteomics and metabolomics tools, we have comprehensive and scalable methods to analyze the genes, transcripts, proteins, and metabolites of a multitude of biological systems. Despite the fascinating new molecular insights at the genome, transcriptome, proteome and metabolome scale, we are still far from fully understanding cellular organization, cell cycles and biology at the molecular level. Significant advances in sensitivity and depth for both sequencing as well as mass spectrometry-based methods allow the analysis at the single cell and single molecule level. At the same time, new tools are emerging that enable the investigation of molecular interactions throughout the central dogma of molecular biology. In this review, we provide an overview of established and recently developed mass spectrometry-based tools to probe metabolite-protein interactions-from individual interaction pairs to interactions at the proteome-metabolome scale.
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Affiliation(s)
- Paolo Stincone
- University of Tuebingen, CMFI Cluster of Excellence, Interfaculty Institute of Microbiology and Infection Medicine, Tuebingen, Germany
- University of Tuebingen, Center for Plant Molecular Biology, Tuebingen, Germany
| | - Amira Naimi
- University of Marburg, Institute of Pharmaceutical Biology and Biotechnology, Marburg, Germany
| | | | - Raphael Reher
- University of Marburg, Institute of Pharmaceutical Biology and Biotechnology, Marburg, Germany
| | - Daniel Petras
- University of Tuebingen, CMFI Cluster of Excellence, Interfaculty Institute of Microbiology and Infection Medicine, Tuebingen, Germany
- University of California Riverside, Department of Biochemistry, Riverside, USA
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2
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Reid DJ, Thibert S, Zhou M. Dissecting the structural heterogeneity of proteins by native mass spectrometry. Protein Sci 2023; 32:e4612. [PMID: 36851867 PMCID: PMC10031758 DOI: 10.1002/pro.4612] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/01/2023]
Abstract
A single gene yields many forms of proteins via combinations of post-transcriptional/post-translational modifications. Proteins also fold into higher-order structures and interact with other molecules. The combined molecular diversity leads to the heterogeneity of proteins that manifests as distinct phenotypes. Structural biology has generated vast amounts of data, effectively enabling accurate structural prediction by computational methods. However, structures are often obtained heterologously under homogeneous states in vitro. The lack of native heterogeneity under cellular context creates challenges in precisely connecting the structural data to phenotypes. Mass spectrometry (MS) based proteomics methods can profile proteome composition of complex biological samples. Most MS methods follow the "bottom-up" approach, which denatures and digests proteins into short peptide fragments for ease of detection. Coupled with chemical biology approaches, higher-order structures can be probed via incorporation of covalent labels on native proteins that are maintained at the peptide level. Alternatively, native MS follows the "top-down" approach and directly analyzes intact proteins under nondenaturing conditions. Various tandem MS activation methods can dissect the intact proteins for in-depth structural elucidation. Herein, we review recent native MS applications for characterizing heterogeneous samples, including proteins binding to mixtures of ligands, homo/hetero-complexes with varying stoichiometry, intrinsically disordered proteins with dynamic conformations, glycoprotein complexes with mixed modification states, and active membrane protein complexes in near-native membrane environments. We summarize the benefits, challenges, and ongoing developments in native MS, with the hope to demonstrate an emerging technology that complements other tools by filling the knowledge gaps in understanding molecular heterogeneity of proteins. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Deseree J Reid
- Chemical and Biological Signature Sciences, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Stephanie Thibert
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Mowei Zhou
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
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3
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Bui DT, Kitova EN, Mahal LK, Klassen JS. Mass spectrometry-based shotgun glycomics for discovery of natural ligands of glycan-binding proteins. Curr Opin Struct Biol 2022; 77:102448. [PMID: 36088799 DOI: 10.1016/j.sbi.2022.102448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/15/2022] [Accepted: 07/26/2022] [Indexed: 12/14/2022]
Abstract
The non-covalent associations of complex carbohydrates (glycans) with glycan-binding proteins mediate many important physiological and pathophysiological processes. Identifying these interactions is essential to understanding their diverse biological functions and enables the development of new disease treatments and diagnostics. Knowledge of the repertoire of glycans recognized by most glycan-binding proteins and their affinities is incomplete. Mass spectrometry-based screening of natural glycan libraries has emerged as a promising approach to defining the glycan interactome of glycan-binding proteins. Here, we review recent advances in mass spectrometry-based natural library screening that have led to the discovery of glycan ligands of endogenous and exogenous proteins and illuminated their binding specificities.
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Affiliation(s)
- Duong T Bui
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada. https://twitter.com/@Duong_T_Bui
| | - Elena N Kitova
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Lara K Mahal
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - John S Klassen
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
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4
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Garimano N, Scalise ML, Gómez F, Amaral MM, Ibarra C. Intestinal mucus-derived metabolites modulate virulence of a clade 8 enterohemorrhagic Escherichia coli O157:H7. Front Cell Infect Microbiol 2022; 12:975173. [PMID: 36004327 PMCID: PMC9393340 DOI: 10.3389/fcimb.2022.975173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 07/20/2022] [Indexed: 11/24/2022] Open
Abstract
The human colonic mucus is mainly composed of mucins, which are highly glycosylated proteins. The normal commensal colonic microbiota has mucolytic activity and is capable of releasing the monosaccharides contained in mucins, which can then be used as carbon sources by pathogens such as Enterohemorrhagic Escherichia coli (EHEC). EHEC can regulate the expression of some of its virulence factors through environmental sensing of mucus-derived sugars, but its implications regarding its main virulence factor, Shiga toxin type 2 (Stx2), among others, remain unknown. In the present work, we have studied the effects of five of the most abundant mucolytic activity-derived sugars, Fucose (L-Fucose), Galactose (D-Galactose), N-Gal (N-acetyl-galactosamine), NANA (N-Acetyl-Neuraminic Acid) and NAG (N-Acetyl-D-Glucosamine) on EHEC growth, adhesion to epithelial colonic cells (HCT-8), and Stx2 production and translocation across a polarized HCT-8 monolayer. We found that bacterial growth was maximum when using NAG and NANA compared to Galactose, Fucose or N-Gal, and that EHEC adhesion was inhibited regardless of the metabolite used. On the other hand, Stx2 production was enhanced when using NAG and inhibited with the rest of the metabolites, whilst Stx2 translocation was only enhanced when using NANA, and this increase occurred only through the transcellular route. Overall, this study provides insights on the influence of the commensal microbiota on the pathogenicity of E. coli O157:H7, helping to identify favorable intestinal environments for the development of severe disease.
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5
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Snyder DT, Harvey SR, Wysocki VH. Surface-induced Dissociation Mass Spectrometry as a Structural Biology Tool. Chem Rev 2022; 122:7442-7487. [PMID: 34726898 PMCID: PMC9282826 DOI: 10.1021/acs.chemrev.1c00309] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Native mass spectrometry (nMS) is evolving into a workhorse for structural biology. The plethora of online and offline preparation, separation, and purification methods as well as numerous ionization techniques combined with powerful new hybrid ion mobility and mass spectrometry systems has illustrated the great potential of nMS for structural biology. Fundamental to the progression of nMS has been the development of novel activation methods for dissociating proteins and protein complexes to deduce primary, secondary, tertiary, and quaternary structure through the combined use of multiple MS/MS technologies. This review highlights the key features and advantages of surface collisions (surface-induced dissociation, SID) for probing the connectivity of subunits within protein and nucleoprotein complexes and, in particular, for solving protein structure in conjunction with complementary techniques such as cryo-EM and computational modeling. Several case studies highlight the significant role SID, and more generally nMS, will play in structural elucidation of biological assemblies in the future as the technology becomes more widely adopted. Cases are presented where SID agrees with solved crystal or cryoEM structures or provides connectivity maps that are otherwise inaccessible by "gold standard" structural biology techniques.
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Affiliation(s)
- Dalton T. Snyder
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210
| | - Sophie R. Harvey
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210,Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210
| | - Vicki H. Wysocki
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210,Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210,Corresponding author:
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6
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Bui DT, Jung J, Kitova EN, Li Z, Willows SD, Boddington ME, Kitov PI, Mason AL, Capicciotti CJ, Mahal LK, Macauley MS, Klassen JS. Mass Spectrometry-Based Shotgun Glycomics Using Labeled Glycan Libraries. Anal Chem 2022; 94:4997-5005. [PMID: 35302744 DOI: 10.1021/acs.analchem.1c04779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mass spectrometry-based shotgun glycomics (MS-SG) is a rapid, sensitive, label-, and immobilization-free approach for the discovery of natural ligands of glycan-binding proteins (GBPs). To perform MS-SG, natural libraries of glycans derived from glycoconjugates in cells or tissues are screened against a target GBP using catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS). Because glycan concentrations are challenging to determine, ligand affinities cannot be directly measured. In principle, relative affinities can be ranked by combining CaR-ESI-MS data with relative concentrations established by hydrophilic interaction liquid chromatography (HILIC) performed on the fluorophore-labeled glycan library. To validate this approach, as well as the feasibility of performing CaR-ESI-MS directly on labeled glycans, libraries of labeled N-glycans extracted from the human monocytic U937 cells or intestinal tissues were labeled with 2-aminobenzamide (2-AB), 2-aminobenzoic acid (2-AA), or procainamide (proA). The libraries were screened against plant and human GBPs with known specificities for α2-3- and α2-6-linked sialosides and quantified by HILIC. Dramatic differences, in some cases, were found for affinity rankings obtained with libraries labeled with different fluorophores, as well as those produced using the combined unlabeled/labeled library approach. The origin of these differences could be explained by differential glycan labeling efficiencies, the impact of specific labels on glycan affinities for the GBPs, and the relative efficiency of release of ligands from GBPs in CaR-ESI-MS. Overall, the results of this study suggest that the 2-AB(CaR-ESI-MS)/2-AB(HILIC) combination provides the most reliable description of the binding specificities of GBPs for N-glycans and is recommended for MS-SG applications.
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Affiliation(s)
- Duong T Bui
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Jaesoo Jung
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Elena N Kitova
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Zhixiong Li
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Steven D Willows
- Division of Gastroenterology and Hepatology, University of Alberta, Edmonton, Alberta, Canada T6G 2E1
| | - Marie E Boddington
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada K7L 3N6
| | - Pavel I Kitov
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Andrew L Mason
- Division of Gastroenterology and Hepatology, University of Alberta, Edmonton, Alberta, Canada T6G 2E1
| | - Chantelle J Capicciotti
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada K7L 3N6.,Department of Chemistry, Queen's University, Kingston, Ontario, Canada K7L 3N6
| | - Lara K Mahal
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Matthew S Macauley
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.,Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2E1
| | - John S Klassen
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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7
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Affiliation(s)
- Ryuta Uraki
- The Research Center for Global Viral Diseases, National Center for Global Health and Medicine Research Institute, Tokyo, Japan.,Division of Virology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yoshihiro Kawaoka
- The Research Center for Global Viral Diseases, National Center for Global Health and Medicine Research Institute, Tokyo, Japan. .,Division of Virology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan. .,Department of Special Pathogens, International Research Center for Infectious Diseases, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan. .,Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA.
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8
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Donor MT, Wilson JW, Shepherd SO, Prell JS. Lipid Head Group Adduction to Soluble Proteins Follows Gas-Phase Basicity Predictions: Dissociation Barriers and Charge Abstraction. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2021; 469:116670. [PMID: 34421332 PMCID: PMC8372978 DOI: 10.1016/j.ijms.2021.116670] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Native mass spectrometry analysis of membrane proteins has yielded many useful insights in recent years with respect to membrane protein-lipid interactions, including identifying specific interactions and even measuring binding affinities based on observed abundances of lipid-bound ions after collision-induced dissociation (CID). However, the behavior of non-covalent complexes subjected to extensive CID can in principle be affected by numerous factors related to gas-phase chemistry, including gas-phase basicity (GB) and acidity, shared-proton bonds, and other factors. A recent report from our group showed that common lipids span a wide range of GB values. Notably, phosphatidylcholine (PC) and sphingomyelin lipids are more basic than arginine, suggesting they may strip charge upon dissociation in positive ion mode, while phosphoserine lipids are slightly less basic than arginine and may form especially strong shared-proton bonds. Here, we use CID to probe the strength of non-specific gas-phase interactions between lipid head groups and several soluble proteins, used to deliberately avoid possible physiological protein-lipid interactions. The strengths of the protein-head group interactions follow the trend predicted based solely on lipid and amino acid GBs: phosphoserine (PS) head group forms the strongest bonds with these proteins and out-competes the other head groups studied, while glycerophosphocholine (GPC) head groups form the weakest interactions and dissociate carrying away a positive charge. These results indicate that gas-phase thermochemistry can play an important role in determining which head groups remain bound to protein ions with native-like structures and charge states in positive ion mode upon extensive collisional activation.
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Affiliation(s)
- Micah T. Donor
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene OR 97403-1253
| | - Jesse W. Wilson
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene OR 97403-1253
| | - Samantha O. Shepherd
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene OR 97403-1253
| | - James S. Prell
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene OR 97403-1253
- Materials Science Institute, University of Oregon, 1252 University of Oregon, Eugene, OR 97403-1252
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9
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Frick M, Schwieger C, Schmidt C. Liposomes as Carriers of Membrane-Associated Proteins and Peptides for Mass Spectrometric Analysis. Angew Chem Int Ed Engl 2021; 60:11523-11530. [PMID: 33599387 PMCID: PMC8252038 DOI: 10.1002/anie.202101242] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Indexed: 12/11/2022]
Abstract
Membrane proteins are key players of the cell. Their structure and the interactions they form with their lipid environment are required to understand their function. Here we explore liposomes as membrane mimetics for mass spectrometric analysis of peripheral membrane proteins and peptides. Liposomes are advantageous over other membrane mimetics in that they are easy to prepare, can be varied in size and composition, and are suitable for functional assays. We demonstrate that they dissociate into lipid clusters in the gas phase of a mass spectrometer while intact protein and protein–lipid complexes are retained. We exemplify this approach by employing different liposomes including proteoliposomes of two model peptides/proteins differing in size. Our results pave the way for the general application of liposomes for mass spectrometric analysis of membrane‐associated proteins.
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Affiliation(s)
- Melissa Frick
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Institute for Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Strasse 3a, 06120, Halle, Germany
| | - Christian Schwieger
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Institute for Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Strasse 3a, 06120, Halle, Germany
| | - Carla Schmidt
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Institute for Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Strasse 3a, 06120, Halle, Germany
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10
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Frick M, Schwieger C, Schmidt C. Liposomen als Überträger membranassoziierter Proteine und Peptide für die massenspektrometrische Analyse. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202101242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Melissa Frick
- Interdisziplinäre wissenschaftliche Einrichtung Charles-Tanford-Proteinzentrum Institut für Biochemie und Biotechnologie Martin-Luther-Universität Halle-Wittenberg Kurt-Mothes-Straße 3a 06120 Halle Deutschland
| | - Christian Schwieger
- Interdisziplinäre wissenschaftliche Einrichtung Charles-Tanford-Proteinzentrum Institut für Biochemie und Biotechnologie Martin-Luther-Universität Halle-Wittenberg Kurt-Mothes-Straße 3a 06120 Halle Deutschland
| | - Carla Schmidt
- Interdisziplinäre wissenschaftliche Einrichtung Charles-Tanford-Proteinzentrum Institut für Biochemie und Biotechnologie Martin-Luther-Universität Halle-Wittenberg Kurt-Mothes-Straße 3a 06120 Halle Deutschland
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11
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Scratching the surface: native mass spectrometry of peripheral membrane protein complexes. Biochem Soc Trans 2021; 48:547-558. [PMID: 32129823 PMCID: PMC7192793 DOI: 10.1042/bst20190787] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 02/09/2020] [Accepted: 02/11/2020] [Indexed: 02/06/2023]
Abstract
A growing number of integral membrane proteins have been shown to tune their activity by selectively interacting with specific lipids. The ability to regulate biological functions via lipid interactions extends to the diverse group of proteins that associate only peripherally with the lipid bilayer. However, the structural basis of these interactions remains challenging to study due to their transient and promiscuous nature. Recently, native mass spectrometry has come into focus as a new tool to investigate lipid interactions in membrane proteins. Here, we outline how the native MS strategies developed for integral membrane proteins can be applied to generate insights into the structure and function of peripheral membrane proteins. Specifically, native MS studies of proteins in complex with detergent-solubilized lipids, bound to lipid nanodiscs, and released from native-like lipid vesicles all shed new light on the role of lipid interactions. The unique ability of native MS to capture and interrogate protein–protein, protein–ligand, and protein–lipid interactions opens exciting new avenues for the study of peripheral membrane protein biology.
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12
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Harvey SR, VanAernum ZL, Kostelic MM, Marty MT, Wysocki VH. Probing the structure of nanodiscs using surface-induced dissociation mass spectrometry. Chem Commun (Camb) 2020; 56:15651-15654. [PMID: 33355562 PMCID: PMC7943047 DOI: 10.1039/d0cc05531j] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In the study of membrane proteins and antimicrobial peptides, nanodiscs have emerged as a valuable membrane mimetic to solubilze these molecules in a lipid bilayer. We present the structural characterization of nanodiscs using native mass spectrometry and surface-induced dissociation, which are powerful tools in structural biology.
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Affiliation(s)
- Sophie R Harvey
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH, USA.
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13
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Marty MT. Nanodiscs and Mass Spectrometry: Making Membranes Fly. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2020; 458:116436. [PMID: 33100891 PMCID: PMC7584149 DOI: 10.1016/j.ijms.2020.116436] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Cells are surrounded by a protective lipid bilayer membrane, and membrane proteins in the bilayer control the flow of chemicals, information, and energy across this barrier. Many therapeutics target membrane proteins, and some directly target the lipid membrane itself. However, interactions within biological membranes are challenging to study due to their heterogeneity and insolubility. Mass spectrometry (MS) has become a powerful technique for studying membrane proteins, especially how membrane proteins interact with their surrounding lipid environment. Although detergent micelles are the most common membrane mimetic, nanodiscs are emerging as a promising platform for MS. Nanodiscs, nanoscale lipid bilayers encircled by two scaffold proteins, provide a controllable lipid bilayer for solubilizing membrane proteins. This Young Scientist Perspective focuses on native MS of intact nanodiscs and highlights the unique experiments enabled by making membranes fly, including studying membrane protein-lipid interactions and exploring the specificity of fragile transmembrane peptide complexes. It will also explore current challenges and future perspectives for interfacing nanodiscs with MS.
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Affiliation(s)
- Michael T Marty
- Department of Chemistry and Biochemistry and Bio5 Institute, University of Arizona, Tucson, AZ 85721
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14
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Miller ZM, Zhang JD, Donald WA, Prell JS. Gas-Phase Protonation Thermodynamics of Biological Lipids: Experiment, Theory, and Implications. Anal Chem 2020; 92:10365-10374. [PMID: 32628014 DOI: 10.1021/acs.analchem.0c00613] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Phospholipids are important to cellular function and are a vital structural component of plasma and organelle membranes. These membranes isolate the cell from its environment, allow regulation of the internal concentrations of ions and small molecules, and host diverse types of membrane proteins. It remains extremely challenging to identify specific membrane protein-lipid interactions and their relative strengths. Native mass spectrometry, an intrinsically gas-phase method, has recently been demonstrated as a promising tool for identifying endogenous protein-lipid interactions. However, to what extent the identified interactions reflect solution- versus gas-phase binding strengths is not known. Here, the "Extended" Kinetic Method and ab initio computations at three different levels of theory are used to experimentally and theoretically determine intrinsic gas-phase basicities (GB, ΔG for deprotonation of the protonated base) and proton affinities (PA, ΔH for deprotonation of the protonated base) of six lipids representing common phospholipid types. Gas-phase acidities (ΔG and ΔH for deprotonation) of neutral phospholipids are also evaluated computationally and ranked experimentally. Intriguingly, it is found that two of these phospholipids, sphingomyelin and phosphatidylcholine, have the highest GB of any small, monomeric biomolecules measured to date and are more basic than arginine. Phosphatidylethanolamine and phosphatidylserine are found to be similar in GB to basic amino acids lysine and histidine, and phosphatidic acid and phosphatidylglycerol are the least basic of the six lipid types studied, though still more basic than alanine. Kinetic Method experiments and theory show that the gas-phase acidities of these phospholipids are high but less extreme than their GB values, with phosphatidylserine and phosphatidylglycerol being the most acidic. These results indicate that sphingomyelin and phosphatidylcholine lipids can act as charge-reducing agents when dissociated from native membrane protein-lipid complexes in the gas phase and provide a straightforward model to explain the results of several recent native mass spectrometry studies of protein-lipid complexes.
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Affiliation(s)
- Zachary M Miller
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403-1253, United States
| | - J Diana Zhang
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia, 2052
| | - W Alexander Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia, 2052
| | - James S Prell
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403-1253, United States.,Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1252, United States
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15
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Zhang G, Keener JE, Marty MT. Measuring Remodeling of the Lipid Environment Surrounding Membrane Proteins with Lipid Exchange and Native Mass Spectrometry. Anal Chem 2020; 92:5666-5669. [PMID: 32250609 DOI: 10.1021/acs.analchem.0c00786] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Due to their crucial biochemical roles, membrane proteins are important drug targets. Although it is clear that lipids can influence membrane protein function, the chemistry of lipid binding remains difficult to study because protein-lipid interactions are polydisperse, competitive, and transient. Furthermore, detergents, which are often used to solubilize membrane proteins in micelles, may disrupt lipid interactions that occur in bilayers. Here, we present two new approaches to quantify protein-lipid interactions in bilayers and understand how membrane proteins remodel their surrounding lipid environment. First, we used mass spectrometry (MS) to measure the exchange of lipids between lipoprotein nanodiscs with and without an embedded membrane protein. Shifts in the lipid distribution toward the membrane protein nanodiscs revealed lipid binding, and titrations allowed measurement of the optimal lipid composition for the membrane protein. Second, we used native or nondenaturing MS to ionize membrane protein nanodiscs with heterogeneous lipids. Ejecting the membrane protein complex with bound lipids in the mass spectrometer revealed enrichment of specific lipids around the membrane protein. Both new approaches showed that the E. coli ammonium transporter AmtB prefers phosphatidylglycerol lipids overall but has a minor affinity for phosphatidylcholine lipids.
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16
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Han L, Kitov PI, Li J, Kitova EN, Klassen JS. Probing Heteromultivalent Protein–Glycosphingolipid Interactions using Native Mass Spectrometry and Nanodiscs. Anal Chem 2020; 92:3923-3931. [DOI: 10.1021/acs.analchem.9b05419] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ling Han
- Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2
| | - Pavel I. Kitov
- Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2
| | - Jianing Li
- Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2
| | - Elena N. Kitova
- Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2
| | - John S. Klassen
- Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2
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17
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Kostelic MM, Ryan AM, Reid DJ, Noun JM, Marty MT. Expanding the Types of Lipids Amenable to Native Mass Spectrometry of Lipoprotein Complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:1416-1425. [PMID: 30972726 PMCID: PMC6675625 DOI: 10.1007/s13361-019-02174-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 02/25/2019] [Accepted: 02/25/2019] [Indexed: 05/12/2023]
Abstract
Native mass spectrometry (MS) has become an important tool for the analysis of membrane proteins. Although detergent micelles are the most commonly used method for solubilizing membrane proteins for native MS, nanoscale lipoprotein complexes such as nanodiscs are emerging as a promising complementary approach because they solubilize membrane proteins in a lipid bilayer environment. However, prior native MS studies of intact nanodiscs have employed only a limited set of phospholipids that are similar in mass. Here, we extend the range of lipids that are amenable to native MS of nanodiscs by combining lipids with masses that are simple integer multiples of each other. Although these lipid combinations create complex distributions, overlap between resonant peak series allows interpretation of nanodisc spectra containing glycolipids, sterols, and cardiolipin. We also investigate the gas-phase stability of nanodiscs with these new lipids towards collisional activation. We observe that negative ionization mode or charge reduction stabilizes nanodiscs and is essential to preserving labile lipids such as sterols. These new approaches to native MS of nanodiscs will enable future studies of membrane proteins embedded in model membranes that more accurately mimic natural bilayers. Graphical Abstract.
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Affiliation(s)
- Marius M Kostelic
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E University Blvd, Tucson, AZ, 85721, USA
| | - Alex M Ryan
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E University Blvd, Tucson, AZ, 85721, USA
| | - Deseree J Reid
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E University Blvd, Tucson, AZ, 85721, USA
| | - Jibriel M Noun
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E University Blvd, Tucson, AZ, 85721, USA
| | - Michael T Marty
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E University Blvd, Tucson, AZ, 85721, USA.
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18
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El-Hawiet A, Chen Y, Shams-Ud-Doha K, Kitova EN, Kitov PI, Bode L, Hage N, Falcone FH, Klassen JS. Screening natural libraries of human milk oligosaccharides against lectins using CaR-ESI-MS. Analyst 2018; 143:536-548. [PMID: 29239412 DOI: 10.1039/c7an01397c] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Human milk oligosaccharides (HMOs) afford many health benefits to breast-fed infants, such as protection against infection and regulation of the immune system, through the formation of non-covalent interactions with protein receptors. However, the molecular details of these interactions are poorly understood. Here, we describe the application of catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) for screening natural libraries of HMOs against lectins. The HMOs in the libraries were first identified based on molecular weights (MWs), ion mobility separation arrival times (IMS-ATs) and collision-induced dissociation (CID) fingerprints of their deprotonated anions. The libraries were then screened against lectins and the ligands identified from the MWs, IMS-ATs and CID fingerprints of HMOs released from the lectin in the gas phase. To demonstrate the assay, four fractions, extracted from pooled human milk and containing ≥35 different HMOs, were screened against a C-terminal fragment of human galectin-3 (hGal-3C), for which the HMOs specificities have been previously investigated, and a fragment of the blood group antigen-binding adhesin (BabA) from Helicobacter pylori, for which the HMO specificities have not been previously established. The structures of twenty-one ligands, corresponding to both neutral and acidic HMOs, of hGal-3C were identified; all twenty-one were previously shown to be ligands for this lectin. The presence of HMO ligands at six other MWs was also ascertained. Application of the assay to BabA revealed nineteen specific HMO structures that are recognized by the protein and HMO ligands at two other MWs. Notably, it was found that BabA exhibits broad specificity for HMOs, and recognizes both neutral HMOs, including non-fucosylated ones, and acidic HMOs. The results of competitive binding experiments indicate that HMOs can interact with BabA at previously unknown binding sites. The affinities of eight purified HMOs for BabA were measured by ESI-MS and found to be in the 103 M-1 to 104 M-1 range.
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Affiliation(s)
- Amr El-Hawiet
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
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19
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Cleary SP, Li H, Bagal D, Loo JA, Campuzano IDG, Prell JS. Extracting Charge and Mass Information from Highly Congested Mass Spectra Using Fourier-Domain Harmonics. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:2067-2080. [PMID: 30003534 PMCID: PMC6330157 DOI: 10.1007/s13361-018-2018-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/30/2018] [Accepted: 06/21/2018] [Indexed: 05/20/2023]
Abstract
Native mass spectra of large, polydisperse biomolecules with repeated subunits, such as lipoprotein Nanodiscs, can often be challenging to analyze by conventional methods. The presence of tens of closely spaced, overlapping peaks in these mass spectra can make charge state, total mass, or subunit mass determinations difficult to measure by traditional methods. Recently, we introduced a Fourier Transform-based algorithm that can be used to deconvolve highly congested mass spectra for polydisperse ion populations with repeated subunits and facilitate identification of the charge states, subunit mass, charge-state-specific, and total mass distributions present in the ion population. Here, we extend this method by investigating the advantages of using overtone peaks in the Fourier spectrum, particularly for mass spectra with low signal-to-noise and poor resolution. This method is illustrated for lipoprotein Nanodisc mass spectra acquired on three common platforms, including the first reported native mass spectrum of empty "large" Nanodiscs assembled with MSP1E3D1 and over 300 noncovalently associated lipids. It is shown that overtone peaks contain nearly identical stoichiometry and charge state information to fundamental peaks but can be significantly better resolved, resulting in more reliable reconstruction of charge-state-specific mass spectra and peak width characterization. We further demonstrate how these parameters can be used to improve results from Bayesian spectral fitting algorithms, such as UniDec. Graphical Abstract ᅟ.
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Affiliation(s)
- Sean P Cleary
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene, OR, 97403-1253, USA
| | - Huilin Li
- Department of Chemistry and Biochemistry, Department of Biological Chemistry, University of California, UCLA/DOE Institute for Genomics and Proteomics, Los Angeles, Los Angeles, CA, 90095, USA
| | - Dhanashri Bagal
- Amgen Discovery Research, Amgen, Inc., 1120 Veterans Blvd, South San Francisco, CA, 94080, USA
| | - Joseph A Loo
- Department of Chemistry and Biochemistry, Department of Biological Chemistry, University of California, UCLA/DOE Institute for Genomics and Proteomics, Los Angeles, Los Angeles, CA, 90095, USA
| | - Iain D G Campuzano
- Molecular Structure and Characterization, Amgen, Inc., Thousand Oaks, CA, 91320, USA
| | - James S Prell
- Department of Chemistry and Biochemistry, 1253 University of Oregon, Eugene, OR, 97403-1253, USA.
- Materials Science Institute, 1252 University of Oregon, Eugene, OR, 97403-1252, USA.
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20
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Steil D, Pohlentz G, Legros N, Mormann M, Mellmann A, Karch H, Müthing J. Combining Mass Spectrometry, Surface Acoustic Wave Interaction Analysis, and Cell Viability Assays for Characterization of Shiga Toxin Subtypes of Pathogenic Escherichia coli Bacteria. Anal Chem 2018; 90:8989-8997. [PMID: 29939014 DOI: 10.1021/acs.analchem.8b01189] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Shiga toxin (Stx)-producing Escherichia coli (STEC) and enterohemorrhagic E. coli (EHEC) as a human pathogenic subgroup of STEC are characterized by releasing Stx AB5-toxin as the major virulence factor. Worldwide disseminated EHEC strains cause sporadic infections and outbreaks in the human population and swine pathogenic STEC strains represent greatly feared pathogens in pig breeding and fattening plants. Among the various Stx subtypes, Stx1a and Stx2a are of eminent clinical importance in human infections being associated with life-threatening hemorrhagic colitis and hemolytic uremic syndrome, whereas Stx2e subtype is associated with porcine edema disease with a generalized fatal outcome for the animals. Binding toward the glycosphingolipid globotriaosylceramide (Gb3Cer) is a common feature of all Stx subtypes analyzed so far. Here, we report on the development of a matched strategy combining (i) miniaturized one-step affinity purification of native Stx subtypes from culture supernatant of bacterial wild-type strains using Gb3-functionalized magnetic beads, (ii) structural analysis and identification of Stx holotoxins by electrospray ionization ion mobility mass spectrometry (ESI MS), (iii) functional Stx-receptor real-time interaction analysis employing the surface acoustic wave (SAW) technology, and (iv) Vero cell culture assays for determining Stx-caused cytotoxic effects. Structural investigations revealed diagnostic tryptic peptide ions for purified Stx1a, Stx2a, and Stx2e, respectively, and functional analysis resulted in characteristic binding kinetics of each Stx subtype. Cytotoxicity studies revealed differing toxin-mediated cell damage ranked with Stx1a > Stx2a > Stx2e. Collectively, this matched procedure represents a promising clinical application for the characterization of life-endangering Stx subtypes at the protein level.
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Affiliation(s)
- Daniel Steil
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany
| | - Gottfried Pohlentz
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany
| | - Nadine Legros
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany
| | - Michael Mormann
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany
| | - Alexander Mellmann
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany.,Interdisciplinary Center for Clinical Research (IZKF) Münster , Domagkstrasse 3 , D-48149 Münster , Germany
| | - Helge Karch
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany.,Interdisciplinary Center for Clinical Research (IZKF) Münster , Domagkstrasse 3 , D-48149 Münster , Germany
| | - Johannes Müthing
- Institute for Hygiene , University of Münster , Robert-Koch-Strasse 41 , D-48149 Münster , Germany.,Interdisciplinary Center for Clinical Research (IZKF) Münster , Domagkstrasse 3 , D-48149 Münster , Germany
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21
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Hunter CD, Guo T, Daskhan G, Richards MR, Cairo CW. Synthetic Strategies for Modified Glycosphingolipids and Their Design as Probes. Chem Rev 2018; 118:8188-8241. [DOI: 10.1021/acs.chemrev.8b00070] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Carmanah D. Hunter
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Tianlin Guo
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Gour Daskhan
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Michele R. Richards
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Christopher W. Cairo
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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22
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Li J, Han L, Li J, Kitova EN, Xiong ZJ, Privé GG, Klassen JS. Detecting Protein-Glycolipid Interactions Using CaR-ESI-MS and Model Membranes: Comparison of Pre-loaded and Passively Loaded Picodiscs. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:1493-1504. [PMID: 29654535 DOI: 10.1007/s13361-018-1936-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 03/01/2018] [Accepted: 03/02/2018] [Indexed: 06/08/2023]
Abstract
Catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS), implemented using model membranes (MMs), is a promising approach for the discovery of glycolipid ligands of glycan-binding proteins (GBPs). Picodiscs (PDs), which are lipid-transporting complexes composed of the human sphingolipid activator protein saposin A and phospholipids, have proven to be useful MMs for such studies. The present work compares the use of conventional (pre-loaded) PDs with passively loaded PDs (PLPDs) for CaR-ESI-MS screening of glycolipids against cholera toxin B subunit homopentamer (CTB5). The pre-loaded PDs were prepared from a mixture of purified glycolipid and phospholipid or a mixture of lipids extracted from tissue, while the PLPDs were prepared by incubating PDs containing only phospholipid with glycolipid-containing lipid mixtures in aqueous solution. Time-dependent changes in the composition of the PLPDs produced by incubation with glycomicelles of the ganglioside GM1 were monitored using collision-induced dissociation of the gaseous PD ions and from the extent of ganglioside binding to CTB5 measured by ESI-MS. GM1 incorporation into PDs was evident within a few hours of incubation. At incubation times ≥ 10 days, GM1 binding to CTB5 was indistinguishable from that observed with pre-loaded PDs produced directly from GM1 at the same concentration. Comparison of ganglioside binding to CTB5 measured for pre-loaded PDs and PLPDs prepared from glycolipids extracted from pig and mouse brain revealed that the PLPDs allow for the detection of a greater number of ganglioside ligands. Together, the results of this study suggest PLPDs may have advantages over conventionally prepared PDs for screening glycolipids against GBPs using CaR-ESI-MS. Graphical Abstract ᅟ.
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Affiliation(s)
- Jun Li
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
| | - Ling Han
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
| | - Jianing Li
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
| | - Elena N Kitova
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
| | - Zi Jian Xiong
- Department of Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Gilbert G Privé
- Department of Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, M5G 1L7, Canada
| | - John S Klassen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada.
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23
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How can native mass spectrometry contribute to characterization of biomacromolecular higher-order structure and interactions? Methods 2018; 144:3-13. [PMID: 29704661 DOI: 10.1016/j.ymeth.2018.04.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 04/03/2018] [Accepted: 04/21/2018] [Indexed: 01/16/2023] Open
Abstract
Native mass spectrometry (MS) is an emerging approach for characterizing biomacromolecular structure and interactions under physiologically relevant conditions. In native MS measurement, intact macromolecules or macromolecular complexes are directly ionized from a non-denaturing solvent, and key noncovalent interactions that hold the complexes together can be preserved for MS analysis in the gas phase. This technique provides unique multi-level structural information such as conformational changes, stoichiometry, topology and dynamics, complementing conventional biophysical techniques. Despite the maturation of native MS and greatly expanded range of applications in recent decades, further dissemination is needed to make the community aware of such a technique. In this review, we attempt to provide an overview of the current body of knowledge regarding major aspects of native MS and explain how such technique contributes to the characterization of biomacromolecular higher-order structure and interactions.
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24
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Reid DJ, Keener JE, Wheeler AP, Zambrano DE, Diesing JM, Reinhardt-Szyba M, Makarov A, Marty MT. Engineering Nanodisc Scaffold Proteins for Native Mass Spectrometry. Anal Chem 2017; 89:11189-11192. [PMID: 29048874 DOI: 10.1021/acs.analchem.7b03569] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lipoprotein nanodiscs are ideally suited for native mass spectrometry because they provide a relatively monodisperse nanoscale lipid bilayer environment for delivering membrane proteins into the gas phase. However, native mass spectrometry of nanodiscs produces complex spectra that can be challenging to assign unambiguously. To simplify interpretation of nanodisc spectra, we engineered a series of mutant membrane scaffold proteins (MSP) that do not affect nanodisc formation but shift the masses of nanodiscs in a controllable way, eliminating isobaric interference from the lipids. Moreover, by mixing two different belts before assembly, the stoichiometry of MSP is encoded in the peak shape, which allows the stoichiometry to be assigned unambiguously from a single spectrum. Finally, we demonstrate the use of mixed belt nanodiscs with embedded membrane proteins to confirm the dissociation of MSP prior to desolvation.
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Affiliation(s)
- Deseree J Reid
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - James E Keener
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Andrew P Wheeler
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Dane Evan Zambrano
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Jessica M Diesing
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | | | | | - Michael T Marty
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
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25
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Li J, Richards MR, Kitova EN, Klassen JS. Delivering Transmembrane Peptide Complexes to the Gas Phase Using Nanodiscs and Electrospray Ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:2054-2065. [PMID: 28681358 DOI: 10.1007/s13361-017-1735-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 05/25/2017] [Accepted: 06/01/2017] [Indexed: 06/07/2023]
Abstract
The gas-phase conformations of dimers of the channel-forming membrane peptide gramicidin A (GA), produced from isobutanol or aqueous solutions of GA-containing nanodiscs (NDs), are investigated using electrospray ionization-ion mobility separation-mass spectrometry (ESI-IMS-MS) and molecular dynamics (MD) simulations. The IMS arrival times measured for (2GA + 2Na)2+ ions from isobutanol reveal three different conformations, with collision cross-sections (Ω) of 683 Å2 (conformation 1, C1), 708 Å2 (C2), and 737 Å2 (C3). The addition of NH4CH3CO2 produced (2GA + 2Na)2+ and (2GA + H + Na)2+ ions, with Ω similar to those of C1, C2, and C3, as well as (2GA + 2H)2+, (2GA + 2NH4)2+, and (2GA + H + NH4)2+ ions, which adopt a single conformation with a Ω similar to that of C2. These results suggest that the nature of the charging agents, imparted by the ESI process, can influence dimer conformation in the gas phase. Notably, the POPC NDs produced exclusively (2GA + 2NH4)2+ dimer ions; the DMPC NDs produced both (2GA + 2H)2+ and (2GA + 2NH4)2+ dimer ions. While the Ω of (2GA + 2H)2+ is similar to that of C2, the (2GA + 2NH4)2+ ions from NDs adopt a more compact structure, with a Ω of 656 Å2. It is proposed that this compact structure corresponds to the ion conducting single stranded head-to-head helical GA dimer. These findings highlight the potential of NDs, combined with ESI, for transferring transmembrane peptide complexes directly from lipid bilayers to the gas phase. Graphical Abstract ᅟ.
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Affiliation(s)
- Jun Li
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Alberta, Canada
| | - Michele R Richards
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Alberta, Canada
| | - Elena N Kitova
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Alberta, Canada
| | - John S Klassen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Alberta, Canada.
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26
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Han L, Morales LC, Richards MR, Kitova EN, Sipione S, Klassen JS. Investigating the Influence of Membrane Composition on Protein–Glycolipid Binding Using Nanodiscs and Proxy Ligand Electrospray Ionization Mass Spectrometry. Anal Chem 2017; 89:9330-9338. [DOI: 10.1021/acs.analchem.7b02094] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Ling Han
- Alberta
Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Luis C. Morales
- Department
of Pharmacology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | - Michele R. Richards
- 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
| | - Simonetta Sipione
- Department
of Pharmacology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | - John S. Klassen
- Alberta
Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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27
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Abstract
Membrane proteins play a most important part in metabolism, signaling, cell motility, transport, development, and many other biochemical and biophysical processes which constitute fundamentals of life on the molecular level. Detailed understanding of these processes is necessary for the progress of life sciences and biomedical applications. Nanodiscs provide a new and powerful tool for a broad spectrum of biochemical and biophysical studies of membrane proteins and are commonly acknowledged as an optimal membrane mimetic system that provides control over size, composition, and specific functional modifications on the nanometer scale. In this review we attempted to combine a comprehensive list of various applications of nanodisc technology with systematic analysis of the most attractive features of this system and advantages provided by nanodiscs for structural and mechanistic studies of membrane proteins.
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Affiliation(s)
- Ilia G Denisov
- Department of Biochemistry and Department of Chemistry, University of Illinois , Urbana, Illinois 61801, United States
| | - Stephen G Sligar
- Department of Biochemistry and Department of Chemistry, University of Illinois , Urbana, Illinois 61801, United States
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28
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Leney AC, Heck AJR. Native Mass Spectrometry: What is in the Name? JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:5-13. [PMID: 27909974 PMCID: PMC5174146 DOI: 10.1007/s13361-016-1545-3] [Citation(s) in RCA: 395] [Impact Index Per Article: 56.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 10/25/2016] [Accepted: 10/28/2016] [Indexed: 05/11/2023]
Abstract
Electrospray ionization mass spectrometry (ESI-MS) is nowadays one of the cornerstones of biomolecular mass spectrometry and proteomics. Advances in sample preparation and mass analyzers have enabled researchers to extract much more information from biological samples than just the molecular weight. In particular, relevant for structural biology, noncovalent protein-protein and protein-ligand complexes can now also be analyzed by MS. For these types of analyses, assemblies need to be retained in their native quaternary state in the gas phase. This initial small niche of biomolecular mass spectrometry, nowadays often referred to as "native MS," has come to maturation over the last two decades, with dozens of laboratories using it to study mostly protein assemblies, but also DNA and RNA-protein assemblies, with the goal to define structure-function relationships. In this perspective, we describe the origins of and (re)define the term native MS, portraying in detail what we meant by "native MS," when the term was coined and also describing what it does (according to us) not entail. Additionally, we describe a few examples highlighting what native MS is, showing its successes to date while illustrating the wide scope this technology has in solving complex biological questions. Graphical Abstract ᅟ.
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Affiliation(s)
- Aneika C Leney
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584CH, Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, 3584CH, Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584CH, Utrecht, The Netherlands.
- Netherlands Proteomics Center, Padualaan 8, 3584CH, Utrecht, The Netherlands.
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29
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Abstract
Membrane proteins play critical physiological roles and make up the majority of drug targets. Due to their generally low expression levels and amphipathic nature, membrane proteins represent challenging molecular entities for biophysical study. Mass spectrometry offers several sensitive approaches to study the biophysics of membrane proteins. By preserving noncovalent interactions in the gas phase and using collisional activation to remove solubilization agents inside the mass spectrometer, native mass spectrometry (MS) is capable of studying isolated assemblies that would be insoluble in aqueous solution, such as membrane protein oligomers and protein-lipid complexes. Conventional methods use detergent to solubilize the protein prior to electrospray ionization. Gas-phase activation inside the mass spectrometer removes the detergent to yield the isolated proteins with bound ligands. This approach has proven highly successful for ionizing membrane proteins. With the appropriate choice of detergents, membrane proteins with bound lipid species can be observed, which allows characterization of protein-lipid interactions. However, detergents have several limitations. They do not necessarily replicate the native lipid bilayer environment, and only a small number of protein-lipid interactions can be resolved. In this Account, we summarize the development of different membrane mimetics as cassettes for MS analysis of membrane proteins. Examples include amphipols, bicelles, and picodiscs with a special emphasis on lipoprotein nanodiscs. Polydispersity and heterogeneity of the membrane mimetic cassette is a critical issue for study by MS. Ever more complex data sets consisting of overlapping protein charge states and multiple lipid-bound entities have required development of new computational, theoretical, and experimental approaches to interpret both mass and ion mobility spectra. We will present the rationale and limitations of these approaches. Starting with the early work on empty nanodiscs, we chart developments that culminate in recent high-resolution studies of membrane protein-lipid complexes ejected from nanodiscs. For the latter, increasing collision energies allowed progressive removal of nanodisc components, beginning with the scaffold proteins and continuing through successive shells of lipids, allowing direct characterization of the stoichiometry of the annular lipid belt that surrounds the membrane protein. We consider future directions for the study of membrane proteins in membrane mimetics, including the development of mixed lipid systems and native bilayer environments. Unambiguous assignment of these heterogeneous systems will rely heavily upon further enhancements in both data analysis protocols and instrumental resolution. We anticipate that these developments will provide new insights into the factors that control dynamic protein-lipid interactions in a variety of tailored and natural lipid environments.
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Affiliation(s)
- Michael T. Marty
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Road, OX1 3QZ (UK)
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85719 (USA)
| | - Kin Kuan Hoi
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Road, OX1 3QZ (UK)
| | - Carol V. Robinson
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Road, OX1 3QZ (UK)
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30
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Han L, Kitova EN, Klassen JS. Detecting Protein-Glycolipid Interactions Using Glycomicelles and CaR-ESI-MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:1878-1886. [PMID: 27549393 DOI: 10.1007/s13361-016-1461-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 06/16/2016] [Accepted: 06/24/2016] [Indexed: 06/06/2023]
Abstract
This study reports on the use of the catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) assay, combined with glycomicelles, as a method for detecting specific interactions between water-soluble proteins and glycolipids (GLs) in aqueous solution. The B subunit homopentamers of cholera toxin (CTB5) and Shiga toxin type 1 B (Stx1B5) and the gangliosides GM1, GM2, GM3, GD1a, GD1b, GT1b, and GD2 served as model systems for this study. The CTB5 exhibits broad specificity for gangliosides and binds to GM1, GM2, GM3, GD1a, GD1b, and GT1b; Stx1B5 does not recognize gangliosides. The CaR-ESI-MS assay was used to analyze solutions of CTB5 or Stx1B5 and individual gangliosides (GM1, GM2, GM3, GD1a, GD1b, GT1b, and GD2) or mixtures thereof. The high affinity interaction of CTB5 with GM1 was successfully detected. However, the apparent affinity, as determined from the mass spectra, is significantly lower than that of the corresponding pentasaccharide or when GM1 is presented in model membranes such as nanodiscs. Interactions between CTB5 and the low affinity gangliosides GD1a, GD1b, and GT1b, as well as GD2, which served as a negative control, were detected; no binding of CTB5 to GM2 or GM3 was observed. The CaR-ESI-MS results obtained for Stx1B5 reveal that nonspecific protein-ganglioside binding can occur during the ESI process, although the extent of binding varies between gangliosides. Consequently, interactions detected for CTB5 with GD1a, GD1b, and GT1b are likely nonspecific in origin. Taken together, these results reveal that the CaR-ESI-MS/glycomicelle approach for detecting protein-GL interactions is prone to false positives and false negatives and must be used with caution. Graphical Abstract <!-- [INSERT GRAPHICAL ABSTRACT TEXT HERE] -->.
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Affiliation(s)
- Ling Han
- Alberta Glycomics Center and Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Elena N Kitova
- Alberta Glycomics Center and Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - John S Klassen
- Alberta Glycomics Center and Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada.
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31
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Li J, Richards MR, Bagal D, Campuzano IDG, Kitova EN, Xiong ZJ, Privé GG, Klassen JS. Characterizing the Size and Composition of Saposin A Lipoprotein Picodiscs. Anal Chem 2016; 88:9524-9531. [PMID: 27532319 DOI: 10.1021/acs.analchem.6b02097] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Saposin A (SapA) lipoprotein discs, also known as picodiscs (PDs), represent an attractive method to solubilize glycolipids for protein interaction studies in aqueous solution. Recent electrospray ionization mass spectrometry (ESI-MS) data suggest that the size and composition of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)-containing PDs at neutral pH differs from those of N,N-dimethyldodecylamine N-oxide determined by X-ray crystallography. Using high-resolution ESI-MS, multiangle laser light scattering (MALLS), and molecular dynamics (MD) simulations, the composition, heterogeneity, and structure of POPC-PDs in aqueous ammonium acetate solutions at pH 4.8 and 6.8 were investigated. The ESI-MS and MALLS data revealed that POPC-PDs consist predominantly of (SapA dimer + iPOPC) complexes, with i = 23-29, and have an average molecular weight (MW) of 38.2 ± 3.3 kDa at pH 4.8. In contrast, in freshly prepared solutions at pH 6.8, POPC-PDs are composed predominantly of (SapA tetramer + iPOPC) complexes, with i = 37-60, with an average MW of 68.0 ± 2.7 kDa. However, the (SapA tetramer + iPOPC) complexes are unstable at neutral pH and convert, over a period of hours, to (SapA trimer + iPOPC) complexes, with i = 29-36, with an average MW of 51.1 ± 2.9 kDa. The results of molecular modeling suggest spheroidal structures for the (SapA dimer + iPOPC), (SapA trimer + iPOPC), and (SapA tetramer + iPOPC) complexes in solution. Comparison of measured collision cross sections (Ω) with values calculated for gaseous (SapA dimer + 26POPC)8+, (SapA trimer + 33POPC)12+, and (SapA tetramer + 42POPC)16+ ions produced from modeling suggests that the solution structures are largely preserved in the gas phase, although the lipids do not maintain regular bilayer orientations.
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Affiliation(s)
- Jun Li
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
| | - Michele R Richards
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
| | - Dhanashri Bagal
- Amgen, Discovery Analytical Sciences, Thousand Oaks, California 91320, United States
| | - Iain D G Campuzano
- Amgen, Discovery Analytical Sciences, Thousand Oaks, California 91320, United States
| | - Elena N Kitova
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
| | - Zi Jian Xiong
- Department of Biochemistry, University of Toronto , Toronto, Ontario M5S 1A8, Canada
| | - Gilbert G Privé
- Department of Biochemistry, University of Toronto , Toronto, Ontario M5S 1A8, Canada.,Princess Margaret Cancer Centre, University Health Network , Toronto, Ontario M5G 1L7, Canada
| | - John S Klassen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
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Han L, Shams-Ud-Doha K, Kitova EN, Klassen JS. Screening Oligosaccharide Libraries against Lectins Using the Proxy Protein Electrospray Ionization Mass Spectrometry Assay. Anal Chem 2016; 88:8224-31. [DOI: 10.1021/acs.analchem.6b02044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Ling Han
- Alberta Glycomics Centre
and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G
2G2
| | - Km Shams-Ud-Doha
- 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
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Hoi KK, Robinson CV, Marty MT. Unraveling the Composition and Behavior of Heterogeneous Lipid Nanodiscs by Mass Spectrometry. Anal Chem 2016; 88:6199-204. [PMID: 27206251 DOI: 10.1021/acs.analchem.6b00851] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mass spectrometry (MS) has emerged as a powerful tool to study membrane protein complexes and protein-lipid interactions. Because they provide a precisely defined lipid bilayer environment, lipoprotein Nanodiscs offer a promising cassette for membrane protein MS analysis. However, heterogeneous lipids create several potential challenges for native MS: additional spectral complexity, ambiguous assignments, and differing gas-phase behaviors. Here, we present strategies to address these challenges and streamline analysis of heterogeneous-lipid Nanodiscs. We show that using two lipids of similar mass limits the complexity of the spectra in heterogeneous Nanodiscs and that the lipid composition can be determined by using a dual Fourier transform approach to obtain the average lipid mass. Further, the relationship between gas-phase behavior, lipid composition, and instrumental polarity was investigated to determine the effects of lipid headgroup chemistry on Nanodisc dissociation mechanisms. These results provide unique mechanistic and methodological insights into characterization of complex and heterogeneous systems by mass spectrometry.
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Affiliation(s)
- Kin Kuan Hoi
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford , South Parks Road, Oxford OX1 3QZ, U.K
| | - Carol V Robinson
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford , South Parks Road, Oxford OX1 3QZ, U.K
| | - Michael T Marty
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford , South Parks Road, Oxford OX1 3QZ, U.K
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34
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Rezaei Darestani R, Winter P, Kitova EN, Tuszynski JA, Klassen JS. Screening Anti-Cancer Drugs against Tubulin using Catch-and-Release Electrospray Ionization Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:876-885. [PMID: 26944280 DOI: 10.1007/s13361-016-1360-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 01/22/2016] [Accepted: 02/01/2016] [Indexed: 06/05/2023]
Abstract
Tubulin, which is the building block of microtubules, plays an important role in cell division. This critical role makes tubulin an attractive target for the development of chemotherapeutic drugs to treat cancer. Currently, there is no general binding assay for tubulin-drug interactions. The present work describes the application of the catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) assay to investigate the binding of colchicinoid drugs to αβ-tubulin dimers extracted from porcine brain. Proof-of-concept experiments using positive (ligands with known affinities) and negative (non-binders) controls were performed to establish the reliability of the assay. The assay was then used to screen a library of seven colchicinoid analogues to test their binding to tubulin and to rank their affinities.
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Affiliation(s)
- Reza Rezaei Darestani
- Department of Chemistry and Alberta Glycomics Center, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Philip Winter
- Department of Oncology, University of Alberta, Edmonton, AB, T6G 1Z2, Canada
| | - Elena N Kitova
- Department of Chemistry and Alberta Glycomics Center, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Jack A Tuszynski
- Department of Oncology, University of Alberta, Edmonton, AB, T6G 1Z2, Canada
| | - John S Klassen
- Department of Chemistry and Alberta Glycomics Center, University of Alberta, Edmonton, AB, T6G 2G2, Canada.
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35
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Li J, Fan X, Kitova EN, Zou C, Cairo CW, Eugenio L, Ng KKS, Xiong ZJ, Privé GG, Klassen JS. Screening Glycolipids Against Proteins in Vitro Using Picodiscs and Catch-and-Release Electrospray Ionization-Mass Spectrometry. Anal Chem 2016; 88:4742-50. [PMID: 27049760 DOI: 10.1021/acs.analchem.6b00043] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This work describes the application of the catch-and-release electrospray ionization-mass spectrometry (CaR-ESI-MS) assay, implemented using picodiscs (complexes comprised of saposin A and lipids, PDs), to screen mixtures of glycolipids (GLs) against water-soluble proteins to detect specific interactions. To demonstrate the reliability of the method, seven gangliosides (GM1, GM2, GM3, GD1a, GD1b, GD2, and GT1b) were incorporated, either individually or as a mixture, into PDs and screened against two lectins: the B subunit homopentamer of cholera toxin (CTB5) and a subfragment of toxin A from Clostridium difficile (TcdA-A2). The CaR-ESI-MS results revealed that CTB5 binds to six of the gangliosides (GM1, GM2, GM3, GD1a, GD1b, and GT1b), while TcdA-A2 binds to five of them (GM1, GM2, GM3, GD1a, and GT1b). These findings are consistent with the measured binding specificities of these proteins for ganglioside oligosaccharides. Screening mixtures of lipids extracted from porcine brain and a human epithelial cell line against CTB5 revealed binding to multiple GM1 isoforms as well as to fucosyl-GM1, which is a known ligand. Finally, a comparison of the present results with data obtained with the CaR-ESI-MS assay implemented using nanodiscs (NDs) revealed that the PDs exhibited similar or superior performance to NDs for protein-GL binding measurements.
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Affiliation(s)
- Jun Li
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
| | - Xuxin Fan
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
| | - Elena N Kitova
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
| | - Chunxia Zou
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
| | - Christopher W Cairo
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
| | - Luiz Eugenio
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Biological Sciences, University of Calgary , Calgary, Alberta, Canada T2N 1N4
| | - Kenneth K S Ng
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Biological Sciences, University of Calgary , Calgary, Alberta, Canada T2N 1N4
| | - Zi Jian Xiong
- Department of Biochemistry, University of Toronto , Toronto, Ontario, Canada M5S 1A8
| | - Gilbert G Privé
- Department of Biochemistry, University of Toronto , Toronto, Ontario, Canada M5S 1A8.,Princess Margaret Cancer Centre, University Health Network , Toronto, Ontario, Canada M5G 1L7
| | - John S Klassen
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2.,Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
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36
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Fagerquist CK, Zaragoza WJ. Shiga toxin 2 subtypes of enterohemorrhagic E. coli O157:H- E32511 analyzed by RT-qPCR and top-down proteomics using MALDI-TOF-TOF-MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:788-799. [PMID: 25667061 DOI: 10.1007/s13361-015-1076-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/07/2015] [Accepted: 01/07/2015] [Indexed: 06/04/2023]
Abstract
We have measured the relative abundance of the B-subunits and mRNA transcripts of two Stx2 subtypes present in Shiga toxin-producing Escherichia coli (STEC) O157:H- strain E32511 using matrix-assisted laser desorption/ionization time-of-flight-time-of-flight tandem mass spectrometry (MALDI-TOF-TOF-MS/MS) with post source decay (PSD) and real time-quantitative polymerase chain reaction (RT-qPCR). Stx2a and Stx2c in STEC strain E32511 were quantified from the integrated peak area of their singly charged disulfide-intact B-subunit ions at m/z ~7819 and m/z ~7774, respectively. We found that the Stx2a subtype was 21-fold more abundant than the Stx2c subtype. The two amino acid substitutions (16D ↔ 16 N and 24D ↔ 24A) that distinguish Stx2a from Stx2c not only result in a mass difference of 45 Da between their respective B-subunits but also result in distinctly different fragmentation channels by MS/MS-PSD because both substitutions involve an aspartic acid (D) residue. Importantly, these two substitutions have also been linked to differences in subtype toxicity. We measured the relative abundances of mRNA transcripts using RT-qPCR and determined that the stx2a transcript is 13-fold more abundant than stx2c transcript. In silico secondary structure analysis of the full mRNA operons of stx2a and stx2c suggest that transcript structural differences may also contribute to a relative increase of Stx2a over Stx2c. In consequence, toxin expression may be under both transcriptional and post-transcriptional control.
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Affiliation(s)
- Clifton K Fagerquist
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Western Regional Research Center, 800 Buchanan Street, Albany, CA, 94710, USA,
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37
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Han L, Kitova EN, Li J, Nikjah S, Lin H, Pluvinage B, Boraston AB, Klassen JS. Protein–Glycolipid Interactions Studied in Vitro Using ESI-MS and Nanodiscs: Insights into the Mechanisms and Energetics of Binding. Anal Chem 2015; 87:4888-96. [DOI: 10.1021/acs.analchem.5b00678] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ling Han
- 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
| | - Jun Li
- Alberta
Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Sanaz Nikjah
- Alberta
Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Hong Lin
- Alberta
Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Benjamin Pluvinage
- Department
of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 3P6
| | - Alisdair B. Boraston
- Department
of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 3P6
| | - John S. Klassen
- Alberta
Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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38
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Leney AC, Rezaei Darestani R, Li J, Nikjah S, Kitova EN, Zou C, Cairo CW, Xiong ZJ, Privé GG, Klassen JS. Picodiscs for facile protein-glycolipid interaction analysis. Anal Chem 2015; 87:4402-8. [PMID: 25803566 DOI: 10.1021/acs.analchem.5b00170] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Protein interactions with glycolipids are implicated in diverse cellular processes. However, the study of protein-glycolipid complexes remains a significant experimental challenge. Here, we describe a powerful new assay that combines electrospray ionization mass spectrometry (ESI-MS) and picodiscs, which are composed of human sphingolipid activator protein saposin A and a small number of phospholipids, to display glycolipids in a lipid environment for protein-glycolipid interaction studies in aqueous solution. Time-resolved measurements of enzyme catalyzed hydrolysis of glycolipid substrates and the detection of low, moderate, and high affinity protein-glycolipid interactions serve to demonstrate the reliability and versatility of the assay.
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Affiliation(s)
| | | | | | | | | | | | | | - Zi Jian Xiong
- §Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - Gilbert G Privé
- §Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada M5S 1A8.,∥Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada M5G 1L7
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39
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Hopper JTS, Robinson CV. Mass spectrometry quantifies protein interactions--from molecular chaperones to membrane porins. Angew Chem Int Ed Engl 2014; 53:14002-15. [PMID: 25354304 DOI: 10.1002/anie.201403741] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Indexed: 12/16/2022]
Abstract
Proteins possess an intimate relationship between their structure and function, with folded protein structures generating recognition motifs for the binding of ligands and other proteins. Mass spectrometry (MS) can provide information on a number of levels of protein structure, from the primary amino acid sequence to its three-dimensional fold and quaternary interactions. Given that MS is a gas-phase technique, with its foundations in analytical chemistry, it is perhaps counter-intuitive to use it to study the structure and non-covalent interactions of proteins that form in solution. Herein we show, however, that MS can go beyond simply preserving protein interactions in the gas phase by providing new insight into dynamic interaction networks, dissociation mechanisms, and the cooperativity of ligand binding. We consider potential pitfalls in data interpretation and place particular emphasis on recent studies that revealed quantitative information about dynamic protein interactions, in both soluble and membrane-embedded assemblies.
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Affiliation(s)
- Jonathan T S Hopper
- Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ (UK)
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40
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Hopper JTS, Robinson CV. Massenspektrometrie zur Quantifizierung von Wechselwirkungen zwischen Proteinen - von molekularen Chaperonen zu Membranporinen. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403741] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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41
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Leney AC, Fan X, Kitova EN, Klassen JS. Nanodiscs and Electrospray Ionization Mass Spectrometry: A Tool for Screening Glycolipids Against Proteins. Anal Chem 2014; 86:5271-7. [DOI: 10.1021/ac4041179] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Aneika C. Leney
- Alberta Glycomics Centre
and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Xuxin Fan
- Alberta Glycomics Centre
and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Elena N. Kitova
- Alberta Glycomics Centre
and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - John S. Klassen
- Alberta Glycomics Centre
and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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Matarrese P, Garofalo T, Manganelli V, Gambardella L, Marconi M, Grasso M, Tinari A, Misasi R, Malorni W, Sorice M. Evidence for the involvement of GD3 ganglioside in autophagosome formation and maturation. Autophagy 2014; 10:750-65. [PMID: 24589479 DOI: 10.4161/auto.27959] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Sphingolipids are structural lipid components of cell membranes, including membrane of organelles, such as mitochondria or endoplasmic reticulum, playing a role in signal transduction as well as in the transport and intermixing of cell membranes. Sphingolipid microdomains, also called lipid rafts, participate in several metabolic and catabolic cell processes, including apoptosis. However, the defined role of lipid rafts in the autophagic flux is still unknown. In the present study we analyzed the role of gangliosides, a class of sphingolipids, in autolysosome morphogenesis in human and murine primary fibroblasts by means of biochemical and analytical cytology methods. Upon induction of autophagy, by using amino acid deprivation as well as tunicamycin, we found that GD3 ganglioside, considered as a paradigmatic raft constituent, actively contributed to the biogenesis and maturation of autophagic vacuoles. In particular, fluorescence resonance energy transfer (FRET) and coimmunoprecipitation analyses revealed that this ganglioside interacts with phosphatidylinositol 3-phosphate and can be detected in immature autophagosomes in association with LC3-II as well as in autolysosomes associated with LAMP1. Hence, it appears as a structural component of autophagic flux. Accordingly, we found that autophagy was significantly impaired by knocking down ST8SIA1/GD3 synthase (ST8 α-N-acetyl-neuraminide α-2,8-sialyltransferase 1) or by altering sphingolipid metabolism with fumonisin B1. Interestingly, exogenous administration of GD3 ganglioside was capable of reactivating the autophagic process inhibited by fumonisin B1. Altogether, these results suggest that gangliosides, via their molecular interaction with autophagy-associated molecules, could be recruited to autophagosome and contribute to morphogenic remodeling, e.g., to changes of membrane curvature and fluidity, finally leading to mature autolysosome formation.
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Affiliation(s)
- Paola Matarrese
- Section of Cell Aging and Degeneration; Department of Drug Research and Evaluation; Istituto Superiore di Sanita; Rome, Italy; Center of Metabolomics; Rome, Italy
| | - Tina Garofalo
- Department of Experimental Medicine; Sapienza University; Rome, Italy
| | | | - Lucrezia Gambardella
- Section of Cell Aging and Degeneration; Department of Drug Research and Evaluation; Istituto Superiore di Sanita; Rome, Italy
| | - Matteo Marconi
- Section of Cell Aging and Degeneration; Department of Drug Research and Evaluation; Istituto Superiore di Sanita; Rome, Italy
| | - Maria Grasso
- Department of Experimental Medicine; Sapienza University; Rome, Italy
| | - Antonella Tinari
- Department of Technology and Health; Istituto Superiore di Sanita, Rome, Italy
| | - Roberta Misasi
- Department of Experimental Medicine; Sapienza University; Rome, Italy
| | - Walter Malorni
- Section of Cell Aging and Degeneration; Department of Drug Research and Evaluation; Istituto Superiore di Sanita; Rome, Italy; Istituto San Raffaele Sulmona; L'Aquila, Italy
| | - Maurizio Sorice
- Department of Experimental Medicine; Sapienza University; Rome, Italy
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43
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Marty MT, Zhang H, Cui W, Gross ML, Sligar SG. Interpretation and deconvolution of nanodisc native mass spectra. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:269-77. [PMID: 24353133 PMCID: PMC3918181 DOI: 10.1007/s13361-013-0782-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 10/27/2013] [Accepted: 11/08/2013] [Indexed: 05/11/2023]
Abstract
Nanodiscs are a promising system for studying gas-phase and solution complexes of membrane proteins and lipids. We previously demonstrated that native electrospray ionization allows mass spectral analysis of intact Nanodisc complexes at single lipid resolution. This report details an improved theoretical framework for interpreting and deconvoluting native mass spectra of Nanodisc lipoprotein complexes. In addition to the intrinsic lipid count and charge distributions, Nanodisc mass spectra are significantly shaped by constructive overlap of adjacent charge states at integer multiples of the lipid mass. We describe the mathematical basis for this effect and develop a probability-based algorithm to deconvolute the underlying mass and charge distributions. The probability-based deconvolution algorithm is applied to a series of dimyristoylphosphatidylcholine Nanodisc native mass spectra and used to provide a quantitative picture of the lipid loss in gas-phase fragmentation.
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Affiliation(s)
- Michael T. Marty
- University of Illinois Urbana-Champaign, Department of Chemistry, Urbana, IL 61801
| | - Hao Zhang
- Washington University in St. Louis, Department of Chemistry, St. Louis, MO 63130
- Washington University in St. Louis, Photosynthetic Antenna Research Center (PARC), St. Louis, MO 63130
| | - Weidong Cui
- Washington University in St. Louis, Department of Chemistry, St. Louis, MO 63130
| | - Michael L. Gross
- Washington University in St. Louis, Department of Chemistry, St. Louis, MO 63130
| | - Stephen G. Sligar
- University of Illinois Urbana-Champaign, Department of Chemistry, Urbana, IL 61801
- University of Illinois Urbana-Champaign, Department of Biochemistry, Urbana, IL 61801
- Address reprint requests to: Stephen G. Sligar, 116 Morrill Hall, 505 S. Goodwin MC-119, Urbana, IL 61801, , Phone: 217-244-7395, Fax: 217-265-4073
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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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Zhang Y, Deng L, Kitova EN, Klassen JS. Dissociation of multisubunit protein-ligand complexes in the gas phase. Evidence for ligand migration. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2013; 24:1573-1583. [PMID: 23943432 DOI: 10.1007/s13361-013-0712-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 06/19/2013] [Accepted: 06/27/2013] [Indexed: 06/02/2023]
Abstract
The results of collision-induced dissociation (CID) experiments performed on gaseous protonated and deprotonated ions of complexes of cholera toxin B subunit homopentamer (CTB5) with the pentasaccharide (β-D-Galp-(1→3)-β-D-GalpNAc-(1→4)[α-D-Neu5Ac-(2→3)]-β-D-Galp-(1→4)-β-D-Glcp (GM1)) and corresponding glycosphingolipid (β-D-Galp-(1→3)-β-D-GalpNAc-(1→4)[α-D-Neu5Ac-(2→3)]-β-D-Galp-(1→4)-β-D-Glcp-Cer (GM1-Cer)) ligands, and the homotetramer streptavidin (S4) with biotin (B) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(biotinyl) (Btl), are reported. The protonated (CTB5 + 5GM1)(n+) ions dissociated predominantly by the loss of a single subunit, with the concomitant migration of ligand to another subunit. The simultaneous loss of ligand and subunit was observed as a minor pathway. In contrast, the deprotonated (CTB5 + 5GM1)(n-) ions dissociated preferentially by the loss of deprotonated ligand; the loss of ligand-bound and ligand-free subunit were minor pathways. The presence of ceramide (Cer) promoted ligand migration and the loss of subunit. The main dissociation pathway for the protonated and deprotonated (S4 + 4B)(n+/-) ions, as well as for deprotonated (S4 + 4Btl)(n-) ions, was loss of the ligand. However, subunit loss from the (S4 + 4B)(n+) ions was observed as a minor pathway. The (S4 + 4Btl)(n+) ions dissociated predominantly by the loss of free and ligand-bound subunit. The charge state of the complex and the collision energy were found to have little effect on the relative contribution of the different dissociation channels. Thermally-driven ligand migration between subunits was captured in the results of molecular dynamics simulations performed on protonated (CTB5 + 5GM1)(15+) ions (with a range of charge configurations) at 800 K. Notably, the migration pathway was found to be highly dependent on the charge configuration of the ion. The main conclusion of this study is that the dissociation pathways of multisubunit protein-ligand complexes in the gas phase depend, not only on the native topology of the complex, but also on structural changes that occur upon collisional activation.
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Affiliation(s)
- Yixuan Zhang
- Department of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada
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Lin H, Kitova EN, Klassen JS. Quantifying Protein–Ligand Interactions by Direct Electrospray Ionization-MS Analysis: Evidence of Nonuniform Response Factors Induced by High Molecular Weight Molecules and Complexes. Anal Chem 2013; 85:8919-22. [DOI: 10.1021/ac401936x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hong Lin
- Department
of Chemistry and
Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - Elena N. Kitova
- Department
of Chemistry and
Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
| | - John S. Klassen
- Department
of Chemistry and
Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
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