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Sato K, Yamashita T, Ohuchi H. Mammalian type opsin 5 preferentially activates G14 in Gq-type G proteins triggering intracellular calcium response. J Biol Chem 2023; 299:105020. [PMID: 37423300 PMCID: PMC10432815 DOI: 10.1016/j.jbc.2023.105020] [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: 12/20/2022] [Revised: 06/28/2023] [Accepted: 07/01/2023] [Indexed: 07/11/2023] Open
Abstract
Mammalian type opsin 5 (Opn5m), a UV-sensitive G protein-coupled receptor opsin highly conserved in vertebrates, would provide a common basis for UV sensing from lamprey to humans. However, G protein coupled with Opn5m remains controversial due to variations in assay conditions and the origin of Opn5m across different reports. Here, we examined Opn5m from diverse species using an aequorin luminescence assay and Gα-KO cell line. Beyond the commonly studied major Gα classes, Gαq, Gα11, Gα14, and Gα15 in the Gq class were individually investigated in this study, as they can drive distinct signaling pathways in addition to a canonical calcium response. UV light triggered a calcium response via all the tested Opn5m proteins in 293T cells, which was abolished by Gq-type Gα deletion and rescued by cotransfection with mouse and medaka Gq-type Gα proteins. Opn5m preferentially activated Gα14 and close relatives. Mutational analysis implicated specific regions, including α3-β5 and αG-α4 loops, αG and α4 helices, and the extreme C terminus, in the preferential activation of Gα14 by Opn5m. FISH revealed co-expression of genes encoding Opn5m and Gα14 in the scleral cartilage of medaka and chicken eyes, supporting their physiological coupling. This suggests that the preferential activation of Gα14 by Opn5m is relevant for UV sensing in specific cell types.
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Affiliation(s)
- Keita Sato
- Department of Cytology and Histology, Faculty of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan.
| | - Takahiro Yamashita
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Hideyo Ohuchi
- Department of Cytology and Histology, Faculty of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan.
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2
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Lee HJ, Ehsan M, Zhang X, Katsube S, Munk CF, Wang H, Ahmed W, Kumar A, Byrne B, Loland CJ, Guan L, Liu X, Chae PS. Development of 1,3-acetonedicarboxylate-derived glucoside amphiphiles (ACAs) for membrane protein study. Chem Sci 2022; 13:5750-5759. [PMID: 35694361 PMCID: PMC9116450 DOI: 10.1039/d2sc00539e] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 04/02/2022] [Indexed: 12/31/2022] Open
Abstract
Detergents are extensively used for membrane protein manipulation. Membrane proteins solubilized in conventional detergents are prone to denaturation and aggregation, rendering downstream characterization of these bio-macromolecules difficult. Although many amphiphiles have been developed to overcome the limited efficacy of conventional detergents for protein stabilization, only a handful of novel detergents have so far proved useful for membrane protein structural studies. Here, we introduce 1,3-acetonedicarboxylate-derived amphiphiles (ACAs) containing three glucose units and two alkyl chains as head and tail groups, respectively. The ACAs incorporate two different patterns of alkyl chain attachment to the core detergent unit, generating two sets of amphiphiles: ACA-As (asymmetrically alkylated) and ACA-Ss (symmetrically alkylated). The difference in the attachment pattern of the detergent alkyl chains resulted in minor variation in detergent properties such as micelle size, critical micelle concentration, and detergent behaviors toward membrane protein extraction and stabilization. In contrast, the impact of the detergent alkyl chain length on protein stability was marked. The two C11 variants (ACA-AC11 and ACA-SC11) were most effective at stabilizing the tested membrane proteins. The current study not only introduces new glucosides as tools for membrane protein study, but also provides detergent structure–property relationships important for future design of novel amphiphiles. Newly developed amphiphiles, designated ACAs, are not only efficient at extracting G protein-coupled receptors from the membranes, but also conferred enhanced stability to the receptors compared to the gold standards (DDM and LMNG).![]()
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Affiliation(s)
- Ho Jin Lee
- Department of Bionano Engineering, Hanyang University Ansan 155-88 Korea
| | - Muhammad Ehsan
- Department of Bionano Engineering, Hanyang University Ansan 155-88 Korea
| | - Xiang Zhang
- Beijing Advanced Innovation Center for Structural Biology, School of Medicine, School of Pharmaceutical Sciences, Tsinghua University 100084 Beijing China
| | - Satoshi Katsube
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center Lubbock TX 79430 USA
| | - Chastine F Munk
- Department of Neuroscience, University of Copenhagen Copenhagen DK-2200 Denmark
| | - Haoqing Wang
- Department of Molecular and Cellular Physiology, Stanford University California 94305 USA
| | - Waqar Ahmed
- Department of Bionano Engineering, Hanyang University Ansan 155-88 Korea
| | - Ashwani Kumar
- Department of Bionano Engineering, Hanyang University Ansan 155-88 Korea
| | - Bernadette Byrne
- Department of Life Sciences, Imperial College London London SW7 2AZ UK
| | - Claus J Loland
- Department of Neuroscience, University of Copenhagen Copenhagen DK-2200 Denmark
| | - Lan Guan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center Lubbock TX 79430 USA
| | - Xiangyu Liu
- Beijing Advanced Innovation Center for Structural Biology, School of Medicine, School of Pharmaceutical Sciences, Tsinghua University 100084 Beijing China
| | - Pil Seok Chae
- Department of Bionano Engineering, Hanyang University Ansan 155-88 Korea
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3
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Sadaf A, Kim S, Bae HE, Wang H, Nygaard A, Uegaki Y, Du Y, Munk CF, Katsube S, Sung Lee H, Bae J, Choi CW, Choi HJ, Byrne B, Gellman SH, Guan L, Loland CJ, Kobilka BK, Im W, Chae PS. Conformationally flexible core-bearing detergents with a hydrophobic or hydrophilic pendant: Effect of pendant polarity on detergent conformation and membrane protein stability. Acta Biomater 2021; 128:393-407. [PMID: 33933694 PMCID: PMC8222176 DOI: 10.1016/j.actbio.2021.04.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/31/2021] [Accepted: 04/21/2021] [Indexed: 02/06/2023]
Abstract
Membrane protein structures provide atomic level insight into essential biochemical processes and facilitate protein structure-based drug design. However, the inherent instability of these bio-macromolecules outside lipid bilayers hampers their structural and functional study. Detergent micelles can be used to solubilize and stabilize these membrane-inserted proteins in aqueous solution, thereby enabling their downstream characterizations. Membrane proteins encapsulated in detergent micelles tend to denature and aggregate over time, highlighting the need for development of new amphiphiles effective for protein solubility and stability. In this work, we present newly-designed maltoside detergents containing a pendant chain attached to a glycerol-decorated tris(hydroxymethyl)methane (THM) core, designated GTMs. One set of the GTMs has a hydrophobic pendant (ethyl chain; E-GTMs), and the other set has a hydrophilic pendant (methoxyethoxylmethyl chain; M-GTMs) placed in the hydrophobic-hydrophilic interfaces. The two sets of GTMs displayed profoundly different behaviors in terms of detergent self-assembly and protein stabilization efficacy. These behaviors mainly arise from the polarity difference between two pendants (ethyl and methoxyethoxylmethyl chains) that results in a large variation in detergent conformation between these sets of GTMs in aqueous media. The resulting high hydrophobic density in the detergent micelle interior is likely responsible for enhanced efficacy of the M-GTMs for protein stabilization compared to the E-GTMs and a gold standard detergent DDM. A representative GTM, M-GTM-O12, was more effective for protein stability than some recently developed detergents including LMNG. This is the first case study investigating the effect of pendant polarity on detergent geometry correlated with detergent efficacy for protein stabilization. STATEMENT OF SIGNIFICANCE: This study introduces new amphiphiles for use as biochemical tools in membrane protein studies. We identified a few hydrophilic pendant-bearing amphiphiles such as M-GTM-O11 and M-GTM-O12 that show remarkable efficacy for membrane protein solubilization and stabilization compared to a gold standard DDM, the hydrophobic counterparts (E-GTMs) and a significantly optimized detergent LMNG. In addition, detergent results obtained in the current study reveals the effect of detergent pendant polarity on protein solubility and stability. Thus, the current study represents both significant chemical and conceptual advance. The detergent tools and design principle introduced here advance protein science and facilitate structure-based drug design and development.
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Affiliation(s)
- Aiman Sadaf
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 155-88, South Korea
| | - Seonghoon Kim
- School of Computational Sciences, Korea Institute for Advanced Study, Seoul 02455, South Korea
| | - Hyoung Eun Bae
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 155-88, South Korea
| | - Haoqing Wang
- Department of Molecular and Cellular Physiology, Stanford University, California 94305, USA
| | - Andreas Nygaard
- Department of Neuroscience, University of Copenhagen, Copenhagen, DK-2200, Denmark
| | - Yuki Uegaki
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Yang Du
- Department of Molecular and Cellular Physiology, Stanford University, California 94305, USA
| | - Chastine F Munk
- Department of Neuroscience, University of Copenhagen, Copenhagen, DK-2200, Denmark
| | - Satoshi Katsube
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Hyun Sung Lee
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 155-88, South Korea
| | - Jungnam Bae
- Department of Biological Sciences, Seoul National University, Seoul 08826, South Korea
| | - Chul Won Choi
- Department of Biological Sciences, Seoul National University, Seoul 08826, South Korea
| | - Hee-Jung Choi
- Department of Biological Sciences, Seoul National University, Seoul 08826, South Korea
| | - Bernadette Byrne
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Samuel H Gellman
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin, 53706, USA
| | - Lan Guan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Claus J Loland
- Department of Neuroscience, University of Copenhagen, Copenhagen, DK-2200, Denmark
| | - Brian K Kobilka
- Department of Molecular and Cellular Physiology, Stanford University, California 94305, USA
| | - Wonpil Im
- Department of Biological Sciences, Chemistry, and Bioengineering, Lehigh University, Bethlehem, PA 18015, USA
| | - Pil Seok Chae
- Department of Bionano Engineering, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 155-88, South Korea.
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5
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Feroz H, Meisenhelter J, Jokhadze G, Bruening M, Kumar M. Rapid screening and scale‐up of ultracentrifugation‐free, membrane‐based procedures for purification of His‐tagged membrane proteins. Biotechnol Prog 2019; 35:e2859. [DOI: 10.1002/btpr.2859] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 04/13/2019] [Accepted: 05/03/2019] [Indexed: 12/28/2022]
Affiliation(s)
- Hasin Feroz
- Department of Chemical Engineering The Pennsylvania State University University Park Pennsylvania
| | - Joshua Meisenhelter
- Department of Chemical Engineering The Pennsylvania State University University Park Pennsylvania
| | | | - Merlin Bruening
- Department of Chemical and Biomolecular Engineering University of Notre Dame Notre Dame Indiana
| | - Manish Kumar
- Department of Chemical Engineering The Pennsylvania State University University Park Pennsylvania
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6
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Li Z, Chen G, Chen L, Zhang Y, Dai Z. Solution Properties of Alkyl β‐D‐Maltosides. J SURFACTANTS DETERG 2019. [DOI: 10.1002/jsde.12281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Zhencao Li
- College of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationXiangtan University Xiangtan, 411105 Hunan People's Republic of China Republic of China
| | - Guoyong Chen
- College of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationXiangtan University Xiangtan, 411105 Hunan People's Republic of China Republic of China
| | - Langqiu Chen
- College of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationXiangtan University Xiangtan, 411105 Hunan People's Republic of China Republic of China
| | - Yanhua Zhang
- College of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationXiangtan University Xiangtan, 411105 Hunan People's Republic of China Republic of China
| | - Zhiyong Dai
- Ausnutria Dairy (China) Co. Ltd. Changsha, 410005 Hunan People's Republic of China
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7
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Rodríguez-Abreu C. On the Relationships between the Hydrophilic-Lipophilic Balance and the Nanoarchitecture of Nonionic Surfactant Systems. J SURFACTANTS DETERG 2019. [DOI: 10.1002/jsde.12258] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Carlos Rodríguez-Abreu
- Instituto de Química Avanzada de Cataluña, Consejo Superior de Investigaciones Científicas (IQAC-CSIC) and CIBER de Bioingeniería; Biomateriales y Nanomedicina (CIBER-BBN); Jordi Girona 18-26, 08034, Barcelona Spain
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8
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Feroz H, Kwon H, Peng J, Oh H, Ferlez B, Baker CS, Golbeck JH, Bazan GC, Zydney AL, Kumar M. Improving extraction and post-purification concentration of membrane proteins. Analyst 2019; 143:1378-1386. [PMID: 29220051 DOI: 10.1039/c7an01470h] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Membrane proteins (MPs), despite being critically important drug targets for the pharmaceutical industry, are difficult to study due to challenges in obtaining high yields of functional protein. Most current extraction efforts use specialized non-ionic detergents to solubilize and stabilize MPs, with MPs being concentrated by ultrafiltration (UF). However, many detergents are retained during the UF step, which can destabilize MPs and/or interfere with their characterization. Here, we studied the influence of detergent selection on the extraction and UF-based concentration of biomedically-relevant MPs, the light-driven sodium and chloride transporters, KR2 and halorhodopsin (pHR) which are also model proteins for more complex mammalian rhodopsins. We also designed a flat-bottomed centrifugal filter that can concentrate MPs with enhanced removal of free detergents by promoting concentration polarization (CP). We tested the performance of this new filter using four commonly employed MP detergents, octyl-β-D maltoside (OM), decyl-β-D maltoside (DM), dodecyl-β-D maltoside (DDM) and octyl-β-D glucoside (OG), over a range of detergent and salt concentrations. Detergent passage is significantly higher for the flat-bottomed filter achieving up to 2-fold greater sieving of detergent in DM-solubilized pHR system due to the high degree of CP. We observe more efficient, up to 5-fold higher extraction of KR2 in the presence of a longer 12-carbon alkyl chain detergent, DDM compared to a shorter 8-carbon detergent, OM. Assuming complete binding and elution of the extracted protein, DDM-based extraction of KR2 could lead to a potential 7-fold improvement in purification yields compared to conventional methods which yield ∼1 mg MP per liter of cell culture. However, the longer chain detergents like DDM form larger micelles that are difficult to remove by UF. Thus, there exists a trade-off between choosing a detergent that will enable efficient extraction of MP while showing easier removal during subsequent UF. The extraction efficiency and UF-based separation of detergent micelles provide insights for other applications involving detergent-mediated separation/extraction.
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Affiliation(s)
- Hasin Feroz
- Department of Chemical Engineering, The Pennsylvania State University, Pennsylvania, USA.
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9
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Al-Ali AAA, Steffansen B, Holm R, Nielsen CU. Nonionic surfactants increase digoxin absorption in Caco-2 and MDCKII MDR1 cells: Impact on P-glycoprotein inhibition, barrier function, and repeated cellular exposure. Int J Pharm 2018; 551:270-280. [DOI: 10.1016/j.ijpharm.2018.09.039] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 09/16/2018] [Accepted: 09/17/2018] [Indexed: 12/18/2022]
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10
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Cheng X, Kim JK, Kim Y, Bowie JU, Im W. Molecular dynamics simulation strategies for protein-micelle complexes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:1566-72. [PMID: 26679426 DOI: 10.1016/j.bbamem.2015.12.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/25/2015] [Accepted: 12/03/2015] [Indexed: 01/27/2023]
Abstract
The structure and stability of membrane proteins can vary widely in different detergents and this variability has great practical consequences for working with membrane proteins. Nevertheless, the mechanisms that operate to alter the behavior of proteins in micelles are poorly understood and not predictable. Atomic simulations could provide considerable insight into these mechanisms. Building protein-micelle complexes for simulation is fraught with uncertainty, however, in part because it is often unknown how many detergent molecules are present in the complex. Here, we describe several convenient ways to employ Micelle Builder in CHARMM-GUI to rapidly construct protein-micelle complexes and performed simulations of the isolated voltage-sensor domain of voltage-dependent potassium-selective channel and an antimicrobial peptide papiliocin with varying numbers of detergents. We found that once the detergent number exceeds a threshold, protein-detergent interactions change very little and remain very consistent with experimental observations. Our results provide a platform for future studies of the interplays between protein structure and detergent properties at the atomic level. This article is part of a Special Issue entitled: Membrane Proteins edited by J.C. Gumbart and Sergei Noskov.
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Affiliation(s)
- Xi Cheng
- Department of Molecular Biosciences and Center for Computational Biology, The University of Kansas, 2030 Becker Drive, Lawrence, KS 66047, USA
| | - Jin-Kyoung Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea
| | - Yangmee Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea
| | - James U Bowie
- Department of Chemistry and Biochemistry, UCLA, 611 Charles E. Young Dr. E, Los Angeles, CA 90095-1570, USA
| | - Wonpil Im
- Department of Molecular Biosciences and Center for Computational Biology, The University of Kansas, 2030 Becker Drive, Lawrence, KS 66047, USA.
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11
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Patchornik G, Wachtel E, Kesselman E, Danino D. Cryo-TEM structural analysis of conjugated nonionic engineered-micelles. SOFT MATTER 2014; 10:4922-4928. [PMID: 24874009 DOI: 10.1039/c4sm00462k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Conjugated engineered-micelles, i.e. micelles that are composed of nonionic detergents and hydrophobic chelators and subsequently conjugated in the presence of divalent metal ions, have been shown to be remarkably suited to the task of membrane protein purification, maintaining these proteins in their native state. They also efficiently solubilize highly hydrophobic antibiotics. To date, however, the morphological changes induced in the initially spherical or ellipsoidal micelles by conjugation have not been explored. In this study, the very rapid sample-vitrification protocol of cryogenic transmission electron microscopy (cryo-TEM) has been used to capture structural transformations that engineered-micelles undergo immediately following conjugation with the [(bathophenanthroline)3:Fe(2+)] hydrophobic complex. We found that condensed thread-like aggregates are formed when the detergents used are: octyl β-D-glucopyranoside (OG), octyl β-D-thioglucopyranoside (OTG) or pentaethylene glycol monododecyl ether (C12E5). However, with β-D-maltoside (DM), n-dodecyl β-D-maltoside (DDM) or β-D-glucopyranoside (DDG), lamellar structures, some of which appear as stacked lamellae or multilamellar vesicles (MLV's), were observed. Such architectural changes occur under very mild conditions i.e. low detergent concentration, no temperature or pH alterations and without the presence of any precipitants such as PEG or ammonium sulfate.
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Affiliation(s)
- Guy Patchornik
- Department of Biological Chemistry, Ariel University, 70400, Israel.
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12
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Micellar effect on pentavalent vanadium oxidation of formaldehyde to formic acid in aqueous acid media at room temperature. RESEARCH ON CHEMICAL INTERMEDIATES 2014. [DOI: 10.1007/s11164-014-1635-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
UNLABELLED Flavivirus replication is mediated by a complex machinery that consists of viral enzymes, nonenzymatic viral proteins, and host factors. Many of the nonenzymatic viral proteins, such as NS4B, are associated with the endoplasmic reticulum membrane. How these membrane proteins function in viral replication is poorly understood. Here we report a robust method to express and purify dengue virus (DENV) and West Nile virus NS4B proteins. The NS4B proteins were expressed in Escherichia coli, reconstituted in dodecyl maltoside (DDM) detergent micelles, and purified to >95% homogeneity. The recombinant NS4B proteins dimerized in vitro, as evidenced by gel filtration, chemical cross-linking, and multiangle light scattering experiments. The dimeric form of NS4B was also detected when the protein was expressed alone in cells as well as in cells infected with DENV type 2 (DENV-2). Mutagenesis analysis showed that the cytosolic loop (amino acids 129 to 165) and the C-terminal region (amino acids 166 to 248) are responsible for NS4B dimerization. trans-Complementation experiments showed that (i) two genome-length RNAs containing distinct NS4B lethal mutations could not trans-complement each other, (ii) the replication defect of NS4B mutant RNA could be restored in cells containing DENV-2 replicons, and (iii) expression of wild-type NS4B protein alone was not sufficient to restore the replication of the NS4B mutant RNA. Collectively, the results indicate that trans-complementation of a lethal NS4B mutant RNA requires wild-type NS4B presented from a replication complex. IMPORTANCE The reported expression and purification system has made it possible to study the biochemistry and structure of flavivirus NS4B proteins. The finding of flavivirus NS4B dimerization and the mapping of regions important for NS4B dimerization provide the possibility to inhibit viral replication through blocking NS4B dimerization. The requirement of NS4B in the context of the replication complex for successful trans-complementation enhances our understanding of NS4B in flavivirus replication.
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Chae PS, Kruse AC, Gotfryd K, Rana RR, Cho KH, Rasmussen SGF, Bae HE, Chandra R, Gether U, Guan L, Kobilka BK, Loland CJ, Byrne B, Gellman SH. Novel tripod amphiphiles for membrane protein analysis. Chemistry 2013; 19:15645-51. [PMID: 24123610 PMCID: PMC3947462 DOI: 10.1002/chem.201301423] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/15/2013] [Indexed: 11/08/2022]
Abstract
Integral membrane proteins play central roles in controlling the flow of information and molecules across membranes. Our understanding of membrane protein structures and functions, however, is seriously limited, mainly due to difficulties in handling and analysing these proteins in aqueous solution. The use of a detergent or other amphipathic agents is required to overcome the intrinsic incompatibility between the large lipophilic surfaces displayed by the membrane proteins in their native forms and the polar solvent molecules. Here, we introduce new tripod amphiphiles displaying favourable behaviours toward several membrane protein systems, leading to an enhanced protein solubilisation and stabilisation compared to both conventional detergents and previously described tripod amphiphiles.
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Affiliation(s)
- Pil Seok Chae
- Department of Bionano Engineering, Hanyang University
Ansan, 426-791, (Korea), Fax: (+) 81 31 436 8146
| | - Andrew C. Kruse
- Molecular and Cellular Physiology, Stanford University
Stanford, CA, 94305 (USA)
| | - Kamil Gotfryd
- Department of Neuroscience and Pharmacology University of
Copenhagen, 2200 Copenhagen (Denmark)
| | - Rohini R. Rana
- Department of Life Sciences, Imperial College London
London, SW7 2AZ, (UK)
| | - Kyung Ho Cho
- Department of Bionano Engineering, Hanyang University
Ansan, 426-791, (Korea), Fax: (+) 81 31 436 8146
| | | | - Hyoung Eun Bae
- Department of Bionano Engineering, Hanyang University
Ansan, 426-791, (Korea), Fax: (+) 81 31 436 8146
| | - Richa Chandra
- Molecular and Cellular Physiology, Stanford University
Stanford, CA, 94305 (USA)
| | - Ulrik Gether
- Department of Neuroscience and Pharmacology University of
Copenhagen, 2200 Copenhagen (Denmark)
| | - Lan Guan
- Molecular and Cellular Physiology, Stanford University
Stanford, CA, 94305 (USA)
| | - Brian K. Kobilka
- Molecular and Cellular Physiology, Stanford University
Stanford, CA, 94305 (USA)
| | - Claus J. Loland
- Department of Neuroscience and Pharmacology University of
Copenhagen, 2200 Copenhagen (Denmark)
| | - Bernadette Byrne
- Department of Life Sciences, Imperial College London
London, SW7 2AZ, (UK)
| | - Samuel H. Gellman
- Department of Chemistry, University of Wisconsin-Madison
1101, University Avenue, Madison, WI 53706 (USA)
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Cheng X, Jo S, Lee HS, Klauda JB, Im W. CHARMM-GUI micelle builder for pure/mixed micelle and protein/micelle complex systems. J Chem Inf Model 2013; 53:2171-80. [PMID: 23865552 DOI: 10.1021/ci4002684] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Micelle Builder in CHARMM-GUI, http://www.charmm-gui.org/input/micelle , is a web-based graphical user interface to build pure/mixed micelle and protein/micelle complex systems for molecular dynamics (MD) simulation. The robustness of Micelle Builder is tested by simulating four detergent-only homogeneous micelles of DHPC (dihexanoylphosphatidylcholine), DPC (dodecylphosphocholine), TPC (tetradecylphosphocholine), and SDS (sodium dodecyl sulfate) and comparing the calculated micelle properties with experiments and previous simulations. As a representative protein/micelle model, Pf1 coat protein is modeled and simulated in DHPC micelles with three different numbers of DHPC molecules. While the number of DHPC molecules in direct contact with Pf1 protein converges during the simulation, distinct behavior and geometry of micelles lead to different protein conformations in comparison to that in bilayers. It is our hope that CHARMM-GUI Micelle Builder can be used for simulation studies of various protein/micelle systems to better understand the protein structure and dynamics in micelles as well as distribution of detergents and their dynamics around proteins.
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Affiliation(s)
- Xi Cheng
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, 2030 Becker Drive, Lawrence, Kansas 66047, USA
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16
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Cho KH, Byrne B, Chae PS. Hemifluorinated maltose-neopentyl glycol (HF-MNG) amphiphiles for membrane protein stabilisation. Chembiochem 2013; 14:452-5. [PMID: 23401323 DOI: 10.1002/cbic.201200759] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Indexed: 11/12/2022]
Abstract
SOAP OPERA: Fluorinated amphiphile F4-MNG confers greater stability on Rhodobacter capsulatus superassembly relative to conventional detergents and nonfluorinated MNGs. Such amphiphiles are attractive as tools for membrane science because of their ease of preparation and structure variation.
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Affiliation(s)
- Kyung Ho Cho
- Department of Bionano Engineering, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 426-791, Korea
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Skieterska K, Duchou J, Lintermans B, Van Craenenbroeck K. Detection of G Protein-Coupled Receptor (GPCR) Dimerization by Coimmunoprecipitation. Methods Cell Biol 2013; 117:323-40. [DOI: 10.1016/b978-0-12-408143-7.00017-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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18
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Barbosa LRS, Rigos CF, Yoneda JS, Itri R, Ciancaglini P. Unraveling the Na,K-ATPase alpha(4) subunit assembling induced by large amounts of C(12)E(8) by means of small-angle X-ray scattering. J Phys Chem B 2010; 114:11371-6. [PMID: 20715782 DOI: 10.1021/jp1013829] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the current work, we studied the effect of the nonionic detergent dodecyloctaethyleneglycol, C(12)E(8), on the structure and oligomeric form of the Na,K-ATPase membrane enzyme (sodium-potassium pump) in aqueous suspension, by means of small-angle X-ray scattering (SAXS). Samples composed of 2 mg/mL of Na,K-ATPase, extracted from rabbit kidney medulla, in the presence of a small amount of C(12)E(8) (0.005 mg/mL) and in larger concentrations ranging from 2.7 to 27 mg/mL did not present catalytic activity. Under this condition, an oligomerization of the alpha subunits is expected. SAXS data were analyzed by means of a global fitting procedure supposing that the scattering is due to two independent contributions: one coming from the enzyme and the other one from C(12)E(8) micelles. In the small detergent content (0.005 mg/mL), the SAXS results evidenced that Na,K-ATPase is associated into aggregates larger than (alphabeta)(2) form. When 2.7 mg/mL of C(12)E(8) is added, the data analysis revealed the presence of alpha(4) aggregates in the solution and some free micelles. Increasing the detergent amount up to 27 mg/mL does not disturb the alpha(4) aggregate: just more micelles of the same size and shape are proportionally formed in solution. We believe that our results shed light on a better understanding of how nonionic detergents induce subunit dissociation and reassembling to minimize the exposure of hydrophobic residues to the aqueous solvent.
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Cho H, Zhao Y. Environmental Effects Dominate the Folding of Oligocholates in Solution, Surfactant Micelles, and Lipid Membranes. J Am Chem Soc 2010; 132:9890-9. [DOI: 10.1021/ja103694p] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Hongkwan Cho
- Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111
| | - Yan Zhao
- Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111
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Chae PS, Laible PD, Gellman SH. Tripod Amphiphiles for Membrane Protein Manipulation. MOLECULAR BIOSYSTEMS 2010; 6:89-94. [PMID: 23814603 PMCID: PMC3693755 DOI: 10.1039/b915162c] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Integral membrane proteins (IMPs) are crucial biological components, mediating the transfer of material and information between cells and their environment. Many IMPs have proven to be difficult to isolate and study. High-resolution structural information on this class of proteins is limited, largely because of difficulties in generating soluble forms of such proteins that retain native folding and activity, and difficulties in generating high-quality crystals from such preparations. Isolated IMPs typically do not dissolve in aqueous solution, a property that arises from the large patches of hydrophobic surface necessary for favorable interactions with the core of a lipid bilayer. Detergents are generally required for IMP solubilization: hydrophobic segments of detergent molecules cluster around and shield from water the hydrophobic protein surfaces. The critical role played by detergents in membrane protein manipulation, and the fact that many IMPs are recalcitrant to solubilization and/or crystallization with currently available detergents, suggest that it should be valuable to explore new types of amphiphiles for these purposes. This review constitutes a progress report on our long-term effort to develop a new class of organic molecules, collectively designated "tripod amphiphiles," that are intended as alternatives to conventional detergents for membrane protein manipulation. One long-range goal of this research is to identify new types of amphiphiles that facilitate IMP crystallization. This review should help introduce an important biochemical need to organic chemists, and perhaps inspire new approaches to the problem.
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Affiliation(s)
- Pil Seok Chae
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706 (USA). Fax: (+1) 608-265-4534; Tel: (+1) 608-262-3303
| | - Philip D. Laible
- Biosciences Division Argonne National Laborotory, 9700 South Cass Avenue, Argonne, IL 60439 (USA). Fax: (+1) 630-252-3387
| | - Samuel H. Gellman
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706 (USA). Fax: (+1) 608-265-4534; Tel: (+1) 608-262-3303
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21
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Resistance of Human Erythrocyte Membranes to Triton X-100 and C12E8. J Membr Biol 2008; 227:39-48. [DOI: 10.1007/s00232-008-9142-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Accepted: 11/11/2008] [Indexed: 11/24/2022]
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Kato K, Walde P, Koine N, Ichikawa S, Ishikawa T, Nagahama R, Ishihara T, Tsujii T, Shudou M, Omokawa Y, Kuroiwa T. Temperature-sensitive nonionic vesicles prepared from Span 80 (sorbitan monooleate). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:10762-10770. [PMID: 18720959 DOI: 10.1021/la801581f] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Different types of nonionic vesicles were prepared from commercial Span 80 (also called sorbitan monooleate), as an inexpensive, biocompatible alternative to conventional phospholipid-based vesicles (liposomes). The vesicles were characterized by different techniques and comparison was made with vesicles formed from POPC (1-palmitoyl-2-oleoyl- sn-glycero-3-phosphocholine) or DOPC (1,2-dioleoyl- sn-glycero-3-phosphocholine). Dynamic light scattering measurements, electron microscopy analyses, and two types of fusion assays indicate that Span 80 vesicles are stable for at least 7 days at 4 or 25 degrees C, while storage at 42 degrees C causes irreversible vesicle fusion. This indicates that Span 80 vesicles are thermoresponsive with vesicle fusion occurring at elevated temperature. This property may be related to headgroup dehydration and is certainly not directly linked to the phase transition temperature (Tm) of the vesicles, since the Tm is below -30 degrees C, as determined by differential scanning calorimetry (DSC). The measured Tm value for Span 80 vesicles is lower than in the case of DOPC or POPC, correlating with a higher fluidity of Span 80 vesicles as compared to POPC or DOPC vesicles, as determined with DPH (1,6-diphenyl-1,3,5-hexatriene) as fluorescent membrane probe. High fluidity correlates with increased leakage of entrapped water-soluble dye molecules. Addition of cholesterol and soybean phosphatidylcholine lowers the extent of leakage, allowing a tuning of the bilayer permeability.
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Affiliation(s)
- Keiichi Kato
- Department of Applied Chemistry, Faculty of Engineering, Ehime University, Matsuyama, Japan.
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Rigos CF, Nobre TM, Zaniquelli MED, Ward RJ, Ciancaglini P. The association of Na,K-ATPase subunits studied by circular dichroism, surface tension and dilatational elasticity. J Colloid Interface Sci 2008; 325:478-84. [PMID: 18597766 DOI: 10.1016/j.jcis.2008.06.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 06/05/2008] [Accepted: 06/06/2008] [Indexed: 11/19/2022]
Abstract
Different stoichiometries are observed between alpha and beta subunits of Na,K-ATPase that depend on the method employed to solubilize and purify the enzyme. It is not known whether this variability is due to loss of protein-protein association, or is a result of the replacement of essential phospholipids by detergent molecules. With the aim of understanding the effect of enzyme/surfactant ratio on both the catalytic activity and the enzyme structure, we have investigated the bulk and surface properties of the enzyme. The circular dichroism (CD) spectra, surface tension and dilatational surface elasticity results were compared with the residual ATPase activity of the Na,K-ATPase in different surfactant and protein concentrations. Na,K-ATPase in the (alphabeta)(2) form dissociated to the alphabeta form on dilution, and associated to the (alphabeta)(4) form when concentrated. These different stoichiometries have similar ATPase activities and are in equilibrium at C(12)E(8) concentrations below the CMC (0.053 mg mL(-1)). At detergent concentrations above the CMC the ATPase activity of all forms was abolished, which is concomitant with the dissociation of the alpha and beta subunits.
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Affiliation(s)
- Carolina Fortes Rigos
- Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto SP, Brazil
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Lipfert J, Columbus L, Chu VB, Lesley SA, Doniach S. Size and shape of detergent micelles determined by small-angle X-ray scattering. J Phys Chem B 2007; 111:12427-38. [PMID: 17924686 DOI: 10.1021/jp073016l] [Citation(s) in RCA: 189] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present a systematic analysis of the aggregation number and shape of micelles formed by nine detergents commonly used in the study of membrane proteins. Small-angle X-ray scattering measurements are reported for glucosides with 8 and 9 alkyl carbons (OG/NG), maltosides and phosphocholines with 10 and 12 alkyl carbons (DM/DDM and FC-10/FC-12), 1,2-dihexanoyl-sn-glycero-phosphocholine (DHPC), 1-palmitoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] (LPPG), and 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS). The SAXS intensities are well described by two-component ellipsoid models, with a dense outer shell corresponding to the detergent head groups and a less electron dense hydrophobic core. These models provide an intermediate resolution view of micelle size and shape. In addition, we show that Guinier analysis of the forward scattering intensity can be used to obtain an independent and model-free measurement of the micelle aggregation number and radius of gyration. This approach has the advantage of being easily generalizable to protein-detergent complexes, where simple geometric models are inapplicable. Furthermore, we have discovered that the position of the second maximum in the scattering intensity provides a direct measurement of the characteristic head group-head group spacing across the micelle core. Our results for the micellar aggregation numbers and dimensions agree favorably with literature values as far as they are available. We de novo determine the shape of FC-10, FC-12, DM, LPPG, and CHAPS micelles and the aggregation numbers of FC-10 and OG to be ca. 50 and 250, respectively. Combined, these data provide a comprehensive view of the determinants of micelle formation and serve as a starting point to correlate detergent properties with detergent-protein interactions.
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Affiliation(s)
- Jan Lipfert
- Departments of Physics and Applied Physics, Biophysics Program, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA
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O'Malley MA, Lazarova T, Britton ZT, Robinson AS. High-level expression in Saccharomyces cerevisiae enables isolation and spectroscopic characterization of functional human adenosine A2a receptor. J Struct Biol 2007; 159:166-78. [PMID: 17591446 PMCID: PMC1994815 DOI: 10.1016/j.jsb.2007.05.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Revised: 05/02/2007] [Accepted: 05/04/2007] [Indexed: 10/23/2022]
Abstract
The G-protein coupled receptors (GPCRs) are a class of membrane proteins that trigger cellular responses to external stimuli, and are believed to be targets for nearly half of all pharmaceutical drugs on the market. However, little is known regarding their folding and cellular interactions, as well as what factors are crucial for their activity. Further structural characterization of GPCRs has largely been complicated by problems with expression, purification, and preservation of activity in vitro. Previously, we have demonstrated high-level expression (approximately 4mg/L of culture) of functional human adenosine A(2)a receptor fused to a green fluorescent protein (A(2)aR-GFP) from Saccharomyces cerevisiae. In this work, we re-engineered A(2)aR with a purification tag, developed an adequate purification scheme, and performed biophysical characterization on purified receptors. Milligram amounts per liter of culture of A(2)aR and A(2)aR-GFP were functionally expressed in S. cerevisiae, with a C-terminal deca-histidine tag. Lysis procedures were developed for optimal membrane protein solubilization and recovery through monitoring fluorescence of A(2)aR-GFP-His(10). One-step purification of the protein was achieved through immobilized metal affinity chromatography. After initial solubilization in n-dodecyl-beta-d-maltoside (DDM), a combination of added cholesterol hemisuccinate (CHS) in 3-(3-cholamidopropyl)-dimethylammoniopropane sulfonate (CHAPS) was required to stabilize the functional state of the protein. Isolated A(2)aR under these conditions was found to be largely alpha-helical, and properly incorporated into a mixed-micelle environment. The A(2)a-His(10) receptor was purified in quantities of 6+/-2mg/L of culture, with ligand-binding yields of 1mg/L, although all protein bound to xanthine affinity resin. This represents the highest purified total and functional yields for A(2)aR yet achieved from any heterologous expression system.
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Affiliation(s)
- Michelle A O'Malley
- Department of Chemical Engineering, University of Delaware, 150 Academy Street, Newark, DE 19716, USA
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McCusker EC, Bane SE, O'Malley MA, Robinson AS. Heterologous GPCR expression: a bottleneck to obtaining crystal structures. Biotechnol Prog 2007; 23:540-7. [PMID: 17397185 DOI: 10.1021/bp060349b] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
G protein-coupled receptors (GPCRs) are an important, medically relevant class of integral membrane proteins. Laboratories throughout all disciplines of science devote time and energy into developing practical methods for the discovery, isolation, and characterization of these proteins. Since the crystal structure of rhodopsin was solved 6 years ago, the race to determine high-resolution structures of more GPCRs has gained momentum. Since certain GPCRs are currently produced at sufficient levels for X-ray crystallography trials, it is speculated that heterologous expression of GPCRs may no longer be a bottleneck in obtaining crystal structures. This Review focuses on the current approaches in heterologous expression of GPCRs and explores the problems associated with obtaining crystal structures from GPCRs expressed in different systems. Although milligram amounts of certain GPCRs are attainable, the majority of GPCRs are still either produced at very low levels or not at all. Developing reliable expression techniques for GPCRs is still a major priority for the structural characterization of GPCRs.
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Affiliation(s)
- Emily C McCusker
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19711, USA
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Affiliation(s)
- Michael C Wiener
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908-0736, USA.
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Thévenin D, Lazarova T, Roberts MF, Robinson CR. Oligomerization of the fifth transmembrane domain from the adenosine A2A receptor. Protein Sci 2005; 14:2177-86. [PMID: 15987888 PMCID: PMC2279329 DOI: 10.1110/ps.051409205] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The human adenosine A2A receptor (A(2A)R) belongs to one of the largest family of membrane proteins, the G-protein coupled receptors (GPCRs), characterized by seven transmembrane (TM) helices. Little is known about the determinants of their structures, folding, assembly, activation mechanisms, and oligomeric states. Previous studies in our group showed that peptides corresponding to all seven TM domains form stable helical structures in detergent micelles and lipid vesicles. However, the peptides behave differently; TM5 is the only peptide to have a ratio [theta]222/[theta]208 obtained by circular dichroism (CD) spectroscopy>1. This finding suggested to us that TM5 might self-associate. In the present study, we investigate the unique properties of the TM5 domain. We performed detailed analyses of TM5 peptide behavior in membrane-mimetic environments using CD spectroscopy, fluorescence spectroscopy and Förster resonance energy transfer, and gel electrophoresis. We find that TM5 peptide has the ability to self-associate to form oligomeric structures in various hydrophobic milieus and that these oligomers are highly resistant to temperature and chemical denaturation. We also find that mutation of the full-length A(2A)R at position M193, which is located in the fifth TM domain, noticeably alters A(2A)R monomer: dimer ratio as observed on SDS-PAGE. Our results suggest that parallel association of TM5 dimers may play a role in the known adenosine A2A receptor dimerization. This study represents the first evidence of an individual GPCR transmembrane domain self-association.
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Affiliation(s)
- Damien Thévenin
- Department of Chemistry and Biochemistry, Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA
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