1
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Harrison PJ, Vecerkova T, Clare DK, Quigley A. A review of the approaches used to solve sub-100 kDa membrane proteins by cryo-electron microscopy. J Struct Biol 2023; 215:107959. [PMID: 37004781 DOI: 10.1016/j.jsb.2023.107959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/07/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023]
Abstract
Membrane proteins (MPs) are essential components of all biological membranes, contributing to key cellular functions that include signalling, molecular transport and energy metabolism. Consequently, MPs are important biomedical targets for therapeutics discovery. Despite hardware and software developments in cryo-electron microscopy, as well as MP sample preparation, MPs smaller than 100 kDa remain difficult to study structurally. Significant investment is required to overcome low levels of naturally abundant protein, MP hydrophobicity as well as conformational and compositional instability. Here we have reviewed the sample preparation approaches that have been taken to successfully express, purify and prepare small MPs for analysis by cryo-EM (those with a total solved molecular weight of under 100 kDa), as well as examining the differing approaches towards data processing and ultimately obtaining a structural solution. We highlight common challenges at each stage in the process as well as strategies that have been developed to overcome these issues. Finally, we discuss future directions and opportunities for the study of sub-100 kDa membrane proteins by cryo-EM.
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2
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Kim NH, Kang S, Park GH, Shim G, Kang TH, Yu YG. A robust antibody discovery platform for difficult-to-express G protein-coupled receptors. Protein Sci 2023; 32:e4520. [PMID: 36419382 PMCID: PMC9793966 DOI: 10.1002/pro.4520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 11/25/2022]
Abstract
G protein-coupled receptors (GPCRs) are in the spotlight as drug targets due to the fact that multiple research results have verified the correlation between the activation of GPCRs and disease indications. This is because the GPCRs are present across the cell membranes, which interact with either extracellular ligands or other types of compartments and simultaneously mediate intracellular signaling. Despite the importance of the GPCRs as drug targets, they are too difficult to express in soluble forms. Currently, the difficulty of preparing functional GPCRs and the lack of efficient antibody screening methods are the most challenging steps in the discovery of antibodies targeting GPCRs. In this study, we developed a powerful platform that facilitates isolating GPCR-specific antibodies by obviating difficulties in GPCR preparation. The strategies include (i) conjugation of the P9 peptide, an envelope protein of Pseudomonas phi6, to the N-terminus of GPCRs to improve the expression level of the GPCRs in Escherichia coli, (ii) stabilization of the GPCRs in their active forms with amphiphilic poly-γ-glutamate (APG) to shield the seven hydrophobic transmembrane domains, and (iii) further limiting the size of the APG complex to improve the chance to isolate antibodies targeting the proteins-of-interest. Capitalizing on the above strategies, we could prepare GPCR proteins in their active forms as facile as other general-soluble antigen proteins. Furthermore, this protocol was validated to be successful in discovering three individual GPCR-specific antibodies targeting glucagon-like peptide-1 receptor, C-X-C chemokine receptor type 4, and prostaglandin E2 receptor 4 in this study.
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Affiliation(s)
- Nam Hyuk Kim
- Department of ChemistryKookmin UniversitySeoulRepublic of Korea
- Antibody Research InstituteKookmin UniversitySeoulRepublic of Korea
| | - Sumin Kang
- Department of ChemistryKookmin UniversitySeoulRepublic of Korea
- Antibody Research InstituteKookmin UniversitySeoulRepublic of Korea
| | - Ga Hyeon Park
- Biopharmaceutical Chemistry Major, School of Applied ChemistryKookmin UniversitySeoulRepublic of Korea
| | - Goeun Shim
- Biopharmaceutical Chemistry Major, School of Applied ChemistryKookmin UniversitySeoulRepublic of Korea
| | - Tae Hyun Kang
- Department of ChemistryKookmin UniversitySeoulRepublic of Korea
- Antibody Research InstituteKookmin UniversitySeoulRepublic of Korea
- Biopharmaceutical Chemistry Major, School of Applied ChemistryKookmin UniversitySeoulRepublic of Korea
- Department of Biopharmaceutical ChemistryKookmin UniversitySeoulRepublic of Korea
| | - Yeon Gyu Yu
- Department of ChemistryKookmin UniversitySeoulRepublic of Korea
- Antibody Research InstituteKookmin UniversitySeoulRepublic of Korea
- Biopharmaceutical Chemistry Major, School of Applied ChemistryKookmin UniversitySeoulRepublic of Korea
- Department of Biopharmaceutical ChemistryKookmin UniversitySeoulRepublic of Korea
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3
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Yao H, Cai H, Li D. Fluorescence-Detection Size-Exclusion Chromatography-Based Thermostability Assay for Membrane Proteins. Methods Mol Biol 2023; 2564:299-315. [PMID: 36107350 DOI: 10.1007/978-1-0716-2667-2_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Green fluorescent proteins (GFPs) have lightened up almost every aspect of biological research including protein sciences. In the field of membrane protein structural biology, GFPs have been used widely to monitor membrane protein localization, expression level, the purification process and yield, and the stability inside the cells and in the test tube. Of particular interest is the fluorescence-detector size-exclusion chromatography-based thermostability assay (FSEC-TS). By simple heating and FSEC, the generally applicable method allows rapid assessment of the thermostability of GFP-fused membrane proteins without purification. Here we describe the experimental details and some typical results for the FSEC-TS method.
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Affiliation(s)
| | | | - Dianfan Li
- CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China.
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4
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Piper SJ, Johnson RM, Wootten D, Sexton PM. Membranes under the Magnetic Lens: A Dive into the Diverse World of Membrane Protein Structures Using Cryo-EM. Chem Rev 2022; 122:13989-14017. [PMID: 35849490 PMCID: PMC9480104 DOI: 10.1021/acs.chemrev.1c00837] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Indexed: 11/29/2022]
Abstract
Membrane proteins are highly diverse in both structure and function and can, therefore, present different challenges for structure determination. They are biologically important for cells and organisms as gatekeepers for information and molecule transfer across membranes, but each class of membrane proteins can present unique obstacles to structure determination. Historically, many membrane protein structures have been investigated using highly engineered constructs or using larger fusion proteins to improve solubility and/or increase particle size. Other strategies included the deconstruction of the full-length protein to target smaller soluble domains. These manipulations were often required for crystal formation to support X-ray crystallography or to circumvent lower resolution due to high noise and dynamic motions of protein subdomains. However, recent revolutions in membrane protein biochemistry and cryo-electron microscopy now provide an opportunity to solve high resolution structures of both large, >1 megadalton (MDa), and small, <100 kDa (kDa), drug targets in near-native conditions, routinely reaching resolutions around or below 3 Å. This review provides insights into how the recent advances in membrane biology and biochemistry, as well as technical advances in cryo-electron microscopy, help us to solve structures of a large variety of membrane protein groups, from small receptors to large transporters and more complex machineries.
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Affiliation(s)
- Sarah J. Piper
- Drug
Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
- ARC
Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute
of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
| | - Rachel M. Johnson
- Drug
Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
- ARC
Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute
of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
| | - Denise Wootten
- Drug
Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
- ARC
Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute
of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
| | - Patrick M. Sexton
- Drug
Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
- ARC
Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute
of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria, Australia
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5
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Scott MJ, Jowett A, Orecchia M, Ertl P, Ouro-Gnao L, Ticehurst J, Gower D, Yates J, Poulton K, Harris C, Mullin MJ, Smith KJ, Lewis AP, Barton N, Washburn ML, de Wildt R. Rapid identification of highly potent human anti-GPCR antagonist monoclonal antibodies. MAbs 2021; 12:1755069. [PMID: 32343620 PMCID: PMC7188403 DOI: 10.1080/19420862.2020.1755069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Complex cellular targets such as G protein-coupled receptors (GPCRs), ion channels, and other multi-transmembrane proteins represent a significant challenge for therapeutic antibody discovery, primarily because of poor stability of the target protein upon extraction from cell membranes. To assess whether a limited set of membrane-bound antigen formats could be exploited to identify functional antibodies directed against such targets, we selected a GPCR of therapeutic relevance (CCR1) and identified target binders using an in vitro yeast-based antibody discovery platform (AdimabTM) to expedite hit identification. Initially, we compared two different biotinylated antigen formats overexpressing human CCR1 in a ‘scouting’ approach using a subset of the antibody library. Binders were isolated using streptavidin-coated beads, expressed as yeast supernatants, and screened using a high-throughput binding assay and flow cytometry on appropriate cell lines. The most suitable antigen was then selected to isolate target binders using the full library diversity. This approach identified a combined total of 183 mAbs with diverse heavy chain sequences. A subset of clones exhibited high potencies in primary cell chemotaxis assays, with IC50 values in the low nM/high pM range. To assess the feasibility of any further affinity enhancement, full-length hCCR1 protein was purified, complementary-determining region diversified libraries were constructed from a high and lower affinity mAb, and improved binders were isolated by fluorescence-activated cell sorting selections. A significant affinity enhancement was observed for the lower affinity parental mAb, but not the high affinity mAb. These data exemplify a methodology to generate potent human mAbs for challenging targets rapidly using whole cells as antigen and define a route to the identification of affinity-matured variants if required.
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Affiliation(s)
- Martin J Scott
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Amanda Jowett
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Martin Orecchia
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Peter Ertl
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Larissa Ouro-Gnao
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Julia Ticehurst
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - David Gower
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - John Yates
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Katie Poulton
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Carol Harris
- Department of Protein & Cellular Sciences, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Michael J Mullin
- Department of Protein & Cellular Sciences, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Kathrine J Smith
- Department of Protein & Cellular Sciences, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Alan P Lewis
- Department of Data & Computational Sciences, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Nick Barton
- Department of Data & Computational Sciences, Glaxo Smith Kline Research & Development, Hertfordshire, UK
| | - Michael L Washburn
- Experimental Medicine Unit, Glaxo Smith Kline Research & Development, Collegeville, PA, USA
| | - Ruud de Wildt
- Department of Biopharm Discovery, Glaxo Smith Kline Research & Development, Hertfordshire, UK
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6
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Corvest V, Jawhari A. Solubilization and Stabilization of Native Membrane Proteins for Drug Discovery. Methods Mol Biol 2021; 2247:257-267. [PMID: 33301122 DOI: 10.1007/978-1-0716-1126-5_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Membrane proteins (MPs) are stable in their native lipid environment. To enable structural and functional investigations, MPs need to be extracted from the membrane. This is a critical step that represents the main obstacle for MP biochemistry and structural biology. Here we describe detergent solubilization screening of MPs using dot-blot and Western-blot analyses. Good solubilization conditions are ranked for their best capacity to stabilize MPs using thermal shift assay. The protein functionality is evaluated by radioligand binding (for G-protein-coupled receptor) and ATPase activity (ABC Transporter) and finally the aggregation status as well as protein homogeneity are assessed by Native-polyacrylamide gel, chemical cross-linking, and size exclusion chromatography.
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7
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Cai H, Yao H, Li T, Hutter CAJ, Li Y, Tang Y, Seeger MA, Li D. An improved fluorescent tag and its nanobodies for membrane protein expression, stability assay, and purification. Commun Biol 2020; 3:753. [PMID: 33303987 PMCID: PMC7729955 DOI: 10.1038/s42003-020-01478-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 11/12/2020] [Indexed: 01/08/2023] Open
Abstract
Green fluorescent proteins (GFPs) are widely used to monitor membrane protein expression, purification, and stability. An ideal reporter should be stable itself and provide high sensitivity and yield. Here, we demonstrate that a coral (Galaxea fascicularis) thermostable GFP (TGP) is by such reasons an improved tag compared to the conventional jellyfish GFPs. TGP faithfully reports membrane protein stability at temperatures near 90 °C (20-min heating). By contrast, the limit for the two popular GFPs is 64 °C and 74 °C. Replacing GFPs with TGP increases yield for all four test membrane proteins in four expression systems. To establish TGP as an affinity tag for membrane protein purification, several high-affinity synthetic nanobodies (sybodies), including a non-competing pair, are generated, and the crystal structure of one complex is solved. Given these advantages, we anticipate that TGP becomes a widely used tool for membrane protein structural studies.
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Affiliation(s)
- Hongmin Cai
- University of Chinese Academy of Sciences, National Center for Protein Science Shanghai, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, 200031, Shanghai, China
| | - Hebang Yao
- University of Chinese Academy of Sciences, National Center for Protein Science Shanghai, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, 200031, Shanghai, China
| | - Tingting Li
- University of Chinese Academy of Sciences, National Center for Protein Science Shanghai, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, 200031, Shanghai, China
| | - Cedric A J Hutter
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Yanfang Li
- University of Chinese Academy of Sciences, National Center for Protein Science Shanghai, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, 200031, Shanghai, China
| | - Yannan Tang
- University of Chinese Academy of Sciences, National Center for Protein Science Shanghai, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, 200031, Shanghai, China
| | - Markus A Seeger
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Dianfan Li
- University of Chinese Academy of Sciences, National Center for Protein Science Shanghai, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, 200031, Shanghai, China.
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8
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The rapid "teabag" method for high-end purification of membrane proteins. Sci Rep 2020; 10:16167. [PMID: 32999380 PMCID: PMC7528119 DOI: 10.1038/s41598-020-73285-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/10/2020] [Indexed: 11/17/2022] Open
Abstract
Overproduction and purification of membrane proteins are generally challenging and time-consuming procedures due to low expression levels, misfolding, and low stability once extracted from the membrane. Reducing processing steps and shortening the timespan for purification represent attractive approaches to overcome some of these challenges. We have therefore compared a fast “teabag” purification method with conventional purification for five different membrane proteins (MraY, AQP10, ClC-1, PAR2 and KCC2). Notably, this new approach reduces the purification time significantly, and the quality of the purified membrane proteins is equal to or exceeds conventional methods as assessed by size exclusion chromatography, SDS-PAGE and downstream applications such as ITC, crystallization and cryo-EM. Furthermore, the method is scalable, applicable to a range of affinity resins and allows for parallelization. Consequently, the technique has the potential to substantially simplify purification efforts of membrane proteins in basic and applied sciences.
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9
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Lactobionamide-based fluorinated detergent for functional and structural stabilization of membrane proteins. Methods 2020; 180:19-26. [DOI: 10.1016/j.ymeth.2020.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/07/2020] [Accepted: 02/08/2020] [Indexed: 12/28/2022] Open
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10
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Park SH, Lee JH. Dynamic G Protein-Coupled Receptor Signaling Probed by Solution NMR Spectroscopy. Biochemistry 2020; 59:1065-1080. [PMID: 32092261 DOI: 10.1021/acs.biochem.0c00032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for investigating various dynamic features of G protein-coupled receptor (GPCR) signaling. In this Perspective, we focus on NMR techniques to characterize ligand-dependent conformational dynamics of GPCRs as well as the interaction of GPCRs with their environment and ligands. We also describe circumstances under which each technique should be applied, their advantages and disadvantages, and how they can be combined with other strategies to deepen the understanding of GPCR signaling at the molecular level.
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Affiliation(s)
- Sho Hee Park
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jung Ho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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11
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Novel calixarene-based surfactant enables low dose split inactivated vaccine protection against influenza infection. Vaccine 2019; 38:278-287. [PMID: 31630939 DOI: 10.1016/j.vaccine.2019.10.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 09/30/2019] [Accepted: 10/06/2019] [Indexed: 01/05/2023]
Abstract
Influenza A viruses cause major morbidity and represent a severe global health problem. Current influenza vaccines are mainly egg-based products requiring the split of whole viruses using classical detergents such as Triton X-100, which implies certain limitations. Here, we report the use of the novel calixarene-based surfactant CALX133ACE as an alternative to classical detergents for influenza inactivated split vaccine preparation. We confirmed that CALX133ACE-based split HA antigens are fully functional and quantifiable by the "gold standard" method SRID. Additionally, as in the case of the Triton X-100-based split, the CALX133ACE-based split antigens are stable for at least 6 months at 4 °C. Moreover, immunization of mice with CALX133ACE-based split NYMC X-179A (H1N1) antigens harboring 10 to 30-fold less antigen than the commercialized trivalent inactivated vaccines Vaxigrip® or Fluviral® induced comparable efficient protection and neutralizing antibody responses against A(H1N1)pdm09 infection. Taken together, our results demonstrate for the first time the use of a calixarene-based detergent as an efficient splitting agent for the production of optimized influenza split antigens, paving the way for significant improvement in the vaccine manufacturing process, notably with regard to the current regulation on the prohibition of endocrine disruptors, such as Triton X-100.
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12
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Agez M, Mandon ED, Iwema T, Gianotti R, Limani F, Herter S, Mössner E, Kusznir EA, Huber S, Lauer M, Ringler P, Ferrara C, Klein C, Jawhari A. Biochemical and biophysical characterization of purified native CD20 alone and in complex with rituximab and obinutuzumab. Sci Rep 2019; 9:13675. [PMID: 31548565 PMCID: PMC6757138 DOI: 10.1038/s41598-019-50031-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 08/24/2019] [Indexed: 11/17/2022] Open
Abstract
CD20 is a B-lymphocyte specific integral membrane protein, an activated-glycosylated phosphoprotein expressed on the surface of B-cells and a clinically validated target of monoclonal antibodies such as rituximab, ocrelizumab, ofatumumab and obinutuzumab in the treatment of all B cell lymphomas and leukemias as well as autoimmune diseases. Here, we report the extraction and purification of native CD20 from SUDHL4 and RAMOS cell lines. To improve the protein yield, we applied a calixarene-based detergent approach to solubilize, stabilize and purify native CD20 from HEK293 cells. Size Exclusion Chromatography (SEC) and Analytical Ultracentrifugation show that purified CD20 was non-aggregated and that CD20 oligomerization is concentration dependent. Negative stain electron microscopy and atomic force microscopy revealed homogenous populations of CD20. However, no defined structure could be observed. Interestingly, micellar solubilized and purified CD20 particles adopt uniformly confined nanodroplets which do not fuse and aggregate. Finally, purified CD20 could bind to rituximab and obinutuzumab as demonstrated by SEC, and Surface Plasmon Resonance (SPR). Specificity of binding was confirmed using CD20 antibody mutants to human B-cell lymphoma cells. The strategy described in this work will help investigate CD20 binding with newly developed antibodies and eventually help to optimize them. This approach may also be applicable to other challenging membrane proteins.
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Affiliation(s)
- Morgane Agez
- CALIXAR, 60 avenue Rockefeller 69008, Lyon, France
| | | | - Thomas Iwema
- CALIXAR, 60 avenue Rockefeller 69008, Lyon, France
| | - Reto Gianotti
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Florian Limani
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Sylvia Herter
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Ekkehard Mössner
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Eric A Kusznir
- Roche Pharma Research and Early Development, Lead Discovery, Roche Innovation Center Basel, Basel, Switzerland
| | - Sylwia Huber
- Roche Pharma Research and Early Development, Lead Discovery, Roche Innovation Center Basel, Basel, Switzerland
| | - Matthias Lauer
- Roche Pharma Research and Early Development, Lead Discovery, Roche Innovation Center Basel, Basel, Switzerland
| | - Philippe Ringler
- Center for Cellular Imaging and NanoAnalytics (C-CINA), Biozentrum, University of Basel, Basel, Switzerland
| | - Claudia Ferrara
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Christian Klein
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
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13
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Bonnet C, Guillet P, Igonet S, Meister A, Marconnet A, Keller S, Jawhari A, Durand G. Hybrid Double-Chain Maltose-Based Detergents: Synthesis and Colloidal and Biochemical Evaluation. J Org Chem 2019; 84:10606-10614. [PMID: 31414599 DOI: 10.1021/acs.joc.9b00873] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Four hybrid double-chain surfactants with a maltose polar head were synthesized. The apolar domain consists of a hydrogenated chain, and a partially fluorinated chain made of a propyl hydrogenated spacer terminated by a perfluorinated core of various lengths. Their water solubility was found to be lower than 1 g/L irrespective of the length of both chains. The self-assembling properties of pure hybrids in water were studied by dynamic light scattering and transmission electron microscopy, which revealed the formation of two populations of aggregates with diameters of 8-50 nm and 80-300 nm. When mixed with the classical detergent n-dodecylmaltoside (DDM), the four hybrids were well soluble and formed small mixed micelles. DDM/hybrid mixtures were further evaluated for the extraction of the full-length, wild-type human GPCR adenosine receptor (A2AR), and the bacterial transporter AcrB. The solubilization of A2AR showed extraction efficiencies ranging from 40 to 70%, while that of AcrB reached 60-90%. Finally, three of the hybrids exhibited significant thermostabilization when present as additives. The derivative with a C12-hydrogenated chain and a C4F9-fluorinated chain emerged as the most potent additive exhibiting both good extraction yields of A2AR and AcrB and thermostabilization of A2AR by ∼7 °C.
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Affiliation(s)
- Christophe Bonnet
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France.,CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France
| | - Pierre Guillet
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France.,CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France
| | - Sébastien Igonet
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France.,CALIXAR , 60 Avenue Rockefeller , 69008 Lyon , France
| | - Annette Meister
- ZIK HALOmem and Institute of Biochemistry and Biotechnology , Martin Luther University Halle-Wittenberg , Kurt-Mothes-Str. 3a , D-06120 Halle/Saale , Germany
| | - Anaïs Marconnet
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France.,CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France
| | - Sandro Keller
- Molecular Biophysics , Technische Universität Kaiserslautern (TUK) , Erwin-Schrödinger-Str. 13 , 67663 Kaiserslautern , Germany
| | - Anass Jawhari
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France.,CALIXAR , 60 Avenue Rockefeller , 69008 Lyon , France
| | - Grégory Durand
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France.,CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9 , France
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14
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Dauvergne J, Desuzinges EM, Faugier C, Igonet S, Soulié M, Grousson E, Cornut D, Bonneté F, Durand G, Dejean E, Jawhari A. Glycosylated Amphiphilic Calixarene‐Based Detergent for Functional Stabilization of Native Membrane Proteins. ChemistrySelect 2019. [DOI: 10.1002/slct.201901220] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Elodie Mandon Desuzinges
- CALIXAR 60 avenue Rockefeller 69008 Lyon France
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
| | - Clarisse Faugier
- CALIXAR 60 avenue Rockefeller 69008 Lyon France
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
| | - Sébastien Igonet
- CALIXAR 60 avenue Rockefeller 69008 Lyon France
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
| | - Marine Soulié
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
- Avignon University, Equipe Chimie Bioorganique et Systèmes amphiphiles 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France. Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM)
| | - Emilie Grousson
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
- Avignon University, Equipe Chimie Bioorganique et Systèmes amphiphiles 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France. Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM)
| | - Damien Cornut
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
- Avignon University, Equipe Chimie Bioorganique et Systèmes amphiphiles 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France. Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM)
| | - Françoise Bonneté
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
- Current address: Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099, CNRS, Université de Paris, Institut de Biologie Physico-Chimique 13 rue Pierre et Marie Curie 75005 Paris France
- Avignon University, Equipe Chimie Bioorganique et Systèmes amphiphiles 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France. Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM)
| | - Grégory Durand
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
- Avignon University, Equipe Chimie Bioorganique et Systèmes amphiphiles 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France. Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM)
| | - Emmanuel Dejean
- CALIXAR 60 avenue Rockefeller 69008 Lyon France
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
| | - Anass Jawhari
- CALIXAR 60 avenue Rockefeller 69008 Lyon France
- CHEM2STAB, laboratoire commun 301 rue Baruch de Spinoza – 84916 Avignon cedex 9 France
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15
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Guillet P, Mahler F, Garnier K, Nyame Mendendy Boussambe G, Igonet S, Vargas C, Ebel C, Soulié M, Keller S, Jawhari A, Durand G. Hydrogenated Diglucose Detergents for Membrane-Protein Extraction and Stabilization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4287-4295. [PMID: 30767533 DOI: 10.1021/acs.langmuir.8b02842] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We report herein the design and synthesis of a novel series of alkyl glycoside detergents consisting of a nonionic polar headgroup that comprises two glucose moieties in a branched arrangement (DG), onto which octane-, decane-, and dodecanethiols were grafted leading to ODG, DDG, and DDDG detergents, respectively. Micellization in aqueous solution was studied by isothermal titration calorimetry, 1H NMR spectroscopy, and surface tensiometry. Critical micellar concentration values were found to decrease by a factor of ∼10 for each pair of methylene groups added to the alkyl chain, ranging from ∼0.05 to 9 mM for DDDG and ODG, respectively. Dynamic light scattering and analytical ultracentrifugation sedimentation velocity experiments were used to investigate the size and composition of the micellar aggregates, showing that the aggregation number significantly increased from ∼40 for ODG to ∼80 for DDDG. All new compounds were able to solubilize membrane proteins (MPs) from bacterial membranes, insect cells, as well as the Madin-Darby canine kidney cells. In particular, native human adenosine receptor (A2AR) and bacterial transporter (BmrA) were solubilized efficiently. Striking thermostability improvements of +13 and +8 °C were observed when ODG and DDG were, respectively, applied to wild-type and full-length A2AR. Taken together, this novel detergent series shows promising detergent potency for solubilization and stabilization of membrane proteins (MPs) and thus makes a valuable addition to the chemical toolbox available for extracting and handling these important but challenging MP targets.
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Affiliation(s)
- Pierre Guillet
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
| | - Florian Mahler
- Molecular Biophysics , Technische Universität Kaiserslautern (TUK) , Erwin-Schrödinger-Str. 13 , 67663 Kaiserslautern , Germany
| | - Kelly Garnier
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CALIXAR , 60 Avenue Rockefeller , 69008 Lyon , France
| | - Gildas Nyame Mendendy Boussambe
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
| | - Sébastien Igonet
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CALIXAR , 60 Avenue Rockefeller , 69008 Lyon , France
| | - Carolyn Vargas
- Molecular Biophysics , Technische Universität Kaiserslautern (TUK) , Erwin-Schrödinger-Str. 13 , 67663 Kaiserslautern , Germany
| | - Christine Ebel
- Univ. Grenoble Alpes, CNRS, CEA, CNRS, IBS , F-38000 Grenoble , France
| | - Marine Soulié
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
| | - Sandro Keller
- Molecular Biophysics , Technische Universität Kaiserslautern (TUK) , Erwin-Schrödinger-Str. 13 , 67663 Kaiserslautern , Germany
| | - Anass Jawhari
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CALIXAR , 60 Avenue Rockefeller , 69008 Lyon , France
| | - Grégory Durand
- Equipe Chimie Bioorganique et Systèmes Amphiphiles , Institut des Biomolécules Max Mousseron (UMR 5247 UM-CNRS-ENSCM) & Avignon University , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
- CHEM2STAB , 301 rue Baruch de Spinoza , 84916 Avignon cedex 9, France
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16
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Successful amphiphiles as the key to crystallization of membrane proteins: Bridging theory and practice. Biochim Biophys Acta Gen Subj 2018; 1863:437-455. [PMID: 30419284 DOI: 10.1016/j.bbagen.2018.11.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/31/2018] [Accepted: 11/07/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND Membrane proteins constitute a major group of proteins and are of great significance as pharmaceutical targets, but underrepresented in the Protein Data Bank. Particular reasons are their low expression yields and the constant need for cautious and diligent handling in a sufficiently stable hydrophobic environment substituting for the native membrane. When it comes to protein crystallization, such an environment is often established by detergents. SCOPE OF REVIEW In this review, 475 unique membrane protein X-ray structures from the online data bank "Membrane proteins of known 3D structure" are presented with a focus on the detergents essential for protein crystallization. By systematic analysis of the most successful compounds, including current trends in amphiphile development, we provide general insights for selection and design of detergents for membrane protein crystallization. MAJOR CONCLUSIONS The most successful detergents share common features, giving rise to favorable protein interactions. The hydrophile-lipophile balance concept of well-balanced hydrophilic and hydrophobic detergent portions is still the key to successful protein crystallization. Although a single detergent compound is sufficient in most cases, sometimes a suitable mixture of detergents has to be found to alter the resulting protein-detergent complex. Protein crystals with a high diffraction limit involve a tight crystal packing generally favored by detergents with shorter alkyl chains. GENERAL SIGNIFICANCE The formation of well-diffracting membrane protein crystals strongly depends on suitable surfactants, usually screened in numerous crystallization trials. The here-presented findings provide basic criteria for the assessment of surfactants within the vast space of potential crystallization conditions for membrane proteins.
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17
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Valeur E, Jimonet P. New Modalities, Technologies, and Partnerships in Probe and Lead Generation: Enabling a Mode-of-Action Centric Paradigm. J Med Chem 2018; 61:9004-9029. [DOI: 10.1021/acs.jmedchem.8b00378] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Eric Valeur
- Medicinal Chemistry, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Pepparedsleden 1, Mölndal 431 83, Sweden
| | - Patrick Jimonet
- External Innovation Drug Discovery, Global Business Development & Licensing, Sanofi, 13 quai Jules Guesde, 94400 Vitry-sur-Seine, France
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18
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Igonet S, Raingeval C, Cecon E, Pučić-Baković M, Lauc G, Cala O, Baranowski M, Perez J, Jockers R, Krimm I, Jawhari A. Enabling STD-NMR fragment screening using stabilized native GPCR: A case study of adenosine receptor. Sci Rep 2018; 8:8142. [PMID: 29802269 PMCID: PMC5970182 DOI: 10.1038/s41598-018-26113-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 04/23/2018] [Indexed: 12/27/2022] Open
Abstract
Structural studies of integral membrane proteins have been limited by the intrinsic conformational flexibility and the need to stabilize the proteins in solution. Stabilization by mutagenesis was very successful for structural biology of G protein-coupled receptors (GPCRs). However, it requires heavy protein engineering and may introduce structural deviations. Here we describe the use of specific calixarenes-based detergents for native GPCR stabilization. Wild type, full length human adenosine A2A receptor was used to exemplify the approach. We could stabilize native, glycosylated, non-aggregated and homogenous A2AR that maintained its ligand binding capacity. The benefit of the preparation for fragment screening, using the Saturation-Transfer Difference nuclear magnetic resonance (STD-NMR) experiment is reported. The binding of the agonist adenosine and the antagonist caffeine were observed and competition experiments with CGS-21680 and ZM241385 were performed, demonstrating the feasibility of the STD-based fragment screening on the native A2A receptor. Interestingly, adenosine was shown to bind a second binding site in the presence of the agonist CGS-21680 which corroborates published results obtained with molecular dynamics simulation. Fragment-like compounds identified using STD-NMR showed antagonistic effects on A2AR in the cAMP cellular assay. Taken together, our study shows that stabilization of native GPCRs represents an attractive approach for STD-based fragment screening and drug design.
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Affiliation(s)
| | - Claire Raingeval
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Université Lyon 1, ENS Lyon - 5, rue de la Doua, F-69100, Villeurbanne, France
| | - Erika Cecon
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | | | - Gordan Lauc
- GENOS, Borongajska cesta 83h, 10000, Zagreb, Croatia
| | - Olivier Cala
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Université Lyon 1, ENS Lyon - 5, rue de la Doua, F-69100, Villeurbanne, France
| | - Maciej Baranowski
- SWING Beamline, Synchrotron SOLEIL, L'Orme des Merisiers, BP48, Saint-Aubin, Gif-sur-Yvette, F-91192, France
| | - Javier Perez
- SWING Beamline, Synchrotron SOLEIL, L'Orme des Merisiers, BP48, Saint-Aubin, Gif-sur-Yvette, F-91192, France
| | - Ralf Jockers
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Isabelle Krimm
- Université de Lyon, Institut des Sciences Analytiques, UMR 5280, CNRS, Université Lyon 1, ENS Lyon - 5, rue de la Doua, F-69100, Villeurbanne, France
| | - Anass Jawhari
- CALIXAR, 60 avenue Rockefeller, 69008, Lyon, France.
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19
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Hardy D, Desuzinges Mandon E, Rothnie AJ, Jawhari A. The yin and yang of solubilization and stabilization for wild-type and full-length membrane protein. Methods 2018; 147:118-125. [PMID: 29477816 DOI: 10.1016/j.ymeth.2018.02.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 02/12/2018] [Accepted: 02/18/2018] [Indexed: 11/16/2022] Open
Abstract
Membrane proteins (MP) are stable in their native lipid environment. To enable structural and functional investigations, MP need to be extracted from the membrane. This is a critical step that represents the main obstacle for MP biochemistry and structural biology. General guidelines and rules for membrane protein solubilization remain difficult to establish. This review aims to provide the reader with a comprehensive overview of the general concepts of MP solubilization and stabilization as well as recent advances in detergents innovation. Understanding how solubilization and stabilization are intimately linked is key to facilitate MP isolation toward fundamental structural and functional research as well as drug discovery applications. How to manage the tour de force of destabilizing the lipid bilayer and stabilizing MP at the same time is the holy grail of successful isolation and investigation of such a delicate and fascinating class of proteins.
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Affiliation(s)
- David Hardy
- CALIXAR, 60 Avenue Rockefeller, 69008 Lyon, France; Life & Health Sciences, Aston University, Birmingham B4 7ET, UK
| | | | - Alice J Rothnie
- Life & Health Sciences, Aston University, Birmingham B4 7ET, UK
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20
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Agez M, Schultz P, Medina I, Baker DJ, Burnham MP, Cardarelli RA, Conway LC, Garnier K, Geschwindner S, Gunnarsson A, McCall EJ, Frechard A, Audebert S, Deeb TZ, Moss SJ, Brandon NJ, Wang Q, Dekker N, Jawhari A. Molecular architecture of potassium chloride co-transporter KCC2. Sci Rep 2017; 7:16452. [PMID: 29184062 PMCID: PMC5705597 DOI: 10.1038/s41598-017-15739-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 10/27/2017] [Indexed: 01/15/2023] Open
Abstract
KCC2 is a neuron specific K+-Cl− co-transporter that controls neuronal chloride homeostasis, and is critically involved in many neurological diseases including brain trauma, epilepsies, autism and schizophrenia. Despite significant accumulating data on the biology and electrophysiological properties of KCC2, structure-function relationships remain poorly understood. Here we used calixarene detergent to solubilize and purify wild-type non-aggregated and homogenous KCC2. Specific binding of inhibitor compound VU0463271 was demonstrated using surface plasmon resonance (SPR). Mass spectrometry revealed glycosylations and phosphorylations as expected from functional KCC2. We show by electron microscopy (EM) that KCC2 exists as monomers and dimers in solution. Monomers are organized into “head” and “core” domains connected by a flexible “linker”. Dimers are asymmetrical and display a bent “S-shape” architecture made of four distinct domains and a flexible dimerization interface. Chemical crosslinking in reducing conditions shows that disulfide bridges are involved in KCC2 dimerization. Moreover, we show that adding a tag to the C-terminus is detrimental to KCC2 function. We postulate that the conserved KCC2 C-ter may be at the interface of dimerization. Taken together, our findings highlight the flexible multi-domain structure of KCC2 with variable anchoring points at the dimerization interface and an important C-ter extremity providing the first in-depth functional architecture of KCC2.
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Affiliation(s)
- Morgane Agez
- CALIXAR, 60 avenue Rockefeller, 69008, Lyon, France
| | - Patrick Schultz
- Department of Integrated Structural Biology, IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire) INSERM, U964; CNRS/Strasbourg University, UMR7104 1, rue Laurent Fries, BP10142, 67404, Illkirch, France
| | | | - David J Baker
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - Matthew P Burnham
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Alderley Park, UK
| | - Ross A Cardarelli
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, 02111, USA
| | - Leslie C Conway
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, 02111, USA
| | | | | | - Anders Gunnarsson
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Eileen J McCall
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - Alexandre Frechard
- Department of Integrated Structural Biology, IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire) INSERM, U964; CNRS/Strasbourg University, UMR7104 1, rue Laurent Fries, BP10142, 67404, Illkirch, France
| | - Stéphane Audebert
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Marseille Protéomique, Marseille, France
| | - Tarek Z Deeb
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, 02111, USA
| | - Stephen J Moss
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, 02111, USA.,Department of Neuroscience, Physiology and Pharmacology, University College, London, WC1E, 6BT, UK
| | - Nicholas J Brandon
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, 02111, USA.,Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, MA, USA
| | - Qi Wang
- AstraZeneca Tufts Laboratory for Basic and Translational Neuroscience, Boston, Massachusetts, 02111, USA.,Neuroscience, IMED Biotech Unit, AstraZeneca, Boston, MA, USA
| | - Niek Dekker
- Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden.
| | - Anass Jawhari
- CALIXAR, 60 avenue Rockefeller, 69008, Lyon, France.
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21
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Abstract
To study integral membrane proteins, one has to extract them from the membrane—the step that is typically achieved by the application of detergents. In this mini-review, we summarize the top 10 detergents used for the structural analysis of membrane proteins based on the published results. The aim of this study is to provide the reader with an overview of the main properties of available detergents (critical micelle concentration (CMC) value, micelle size, etc.) and provide an idea of what detergents to may merit further study. Furthermore, we briefly discuss alternative solubilization and stabilization agents, such as polymers.
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