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Buachi C, Thananukul K, Khongphinitbunjong K, Molloy R, Punyamoonwongsa P. A single-step extraction and immobilization of soybean lipolytic enzymes by using a purpose-designed copolymer of styrene and maleic acid as a membrane lysis agent. Heliyon 2024; 10:e31313. [PMID: 38831811 PMCID: PMC11145489 DOI: 10.1016/j.heliyon.2024.e31313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 06/05/2024] Open
Abstract
Approaches aiming to recover proteins without denaturation represent attractive strategies. To accomplish this, a membrane lysis agent based on poly(styrene-alt-maleic acid) or PSMA was synthesized by photopolymerization using Irgacure® 2959 and carbon tetrabromide (CBr4) as a radical initiator and a reversible chain transfer agent, respectively. Structural elucidation of our in-house synthesized PSMA, so-called photo-PSMA, was performed by using NMR spectroscopy. The use of this photo-PSMA in soybean enzyme extraction was also demonstrated for the first time in this study. Without a severe cell rupture, energy input or any organic solvent, recovery of lipolytic enzymes directly into nanometric-sized particles was accomplished in one-step process. Due to the improved structural regularity along the photo-PSMA backbone, the most effective protective reservoir for enzyme immobilization was generated through the PSMA aggregation. Formation of such reservoir enabled soybean enzymes to be shielded from the surroundings and resolved in their full functioning state. This was convinced by the increased specific lipolytic activity to 1,950 mU/mg, significantly higher than those of sodium dodecyl sulfate (SDS) and the two commercially-available PSMA sources (1000P and 2000P). Our photo-PSMA had thus demonstrated its great potential for cell lyse application, especially for soybean hydrolase extraction.
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Affiliation(s)
- Chatmani Buachi
- School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand
| | | | | | - Robert Molloy
- Polymer Research Group, Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand
- Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand
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2
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Iannotta D, A A, Lai A, Nair S, Koifman N, Lappas M, Salomon C, Wolfram J. Chemically-Induced Lipoprotein Breakdown for Improved Extracellular Vesicle Purification. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2307240. [PMID: 38100284 DOI: 10.1002/smll.202307240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/08/2023] [Indexed: 12/17/2023]
Abstract
Extracellular vesicles (EVs) are nanosized biomolecular packages involved in intercellular communication. EVs are released by all cells, making them broadly applicable as therapeutic, diagnostic, and mechanistic components in (patho)physiology. Sample purity is critical for correctly attributing observed effects to EVs and for maximizing therapeutic and diagnostic performance. Lipoprotein contaminants represent a major challenge for sample purity. Lipoproteins are approximately six orders of magnitude more abundant in the blood circulation and overlap in size, shape, and density with EVs. This study represents the first example of an EV purification method based on the chemically-induced breakdown of lipoproteins. Specifically, a styrene-maleic acid (SMA) copolymer is used to selectively breakdown lipoproteins, enabling subsequent size-based separation of the breakdown products from plasma EVs. The use of the polymer followed by tangential flow filtration or size-exclusion chromatography results in improved EV yield, preservation of EV morphology, increased EV markers, and reduced contaminant markers. SMA-based EV purification enables improved fluorescent labeling, reduces interactions with macrophages, and enhances accuracy, sensitivity, and specificity to detect EV biomarkers, indicating benefits for various downstream applications. In conclusion, SMA is a simple and effective method to improve the purity and yield of plasma-derived EVs, which favorably impacts downstream applications.
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Affiliation(s)
- Dalila Iannotta
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Amruta A
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Andrew Lai
- Translational Extracellular Vesicles in Obstetrics and Gynae-Oncology Group, Faculty of Medicine, University of Queensland Centre for Clinical Research, Royal Brisbane and Women's Hospital, The University of Queensland, Brisbane, QLD, 4029, Australia
| | - Soumyalekshmi Nair
- Translational Extracellular Vesicles in Obstetrics and Gynae-Oncology Group, Faculty of Medicine, University of Queensland Centre for Clinical Research, Royal Brisbane and Women's Hospital, The University of Queensland, Brisbane, QLD, 4029, Australia
| | - Na'ama Koifman
- Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Martha Lappas
- University of Melbourne, Department of Obstetrics and Gynaecology, Australia, and Mercy Hospital for Women, 163 Studley Road, Heidelberg, Victoria, 3084, Australia
| | - Carlos Salomon
- Translational Extracellular Vesicles in Obstetrics and Gynae-Oncology Group, Faculty of Medicine, University of Queensland Centre for Clinical Research, Royal Brisbane and Women's Hospital, The University of Queensland, Brisbane, QLD, 4029, Australia
| | - Joy Wolfram
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
- Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX, 77030, USA
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3
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Ayub H, Murray RJ, Kuyler GC, Napier-Khwaja F, Gunner J, Dafforn TR, Klumperman B, Poyner DR, Wheatley M. GPCRs in the round: SMA-like copolymers and SMALPs as a platform for investigating GPCRs. Arch Biochem Biophys 2024; 754:109946. [PMID: 38395122 DOI: 10.1016/j.abb.2024.109946] [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: 11/24/2023] [Revised: 01/21/2024] [Accepted: 02/20/2024] [Indexed: 02/25/2024]
Abstract
G-protein-coupled receptors (GPCRs) are the largest family of membrane proteins, regulate a plethora of physiological responses and are the therapeutic target for 30-40% of clinically-prescribed drugs. They are integral membrane proteins deeply embedded in the plasma membrane where they activate intracellular signalling via coupling to G-proteins and β-arrestin. GPCRs are in intimate association with the bilayer lipids and that lipid environment regulates the signalling functions of GPCRs. This complex lipid 'landscape' is both heterogeneous and dynamic. GPCR function is modulated by bulk membrane properties including membrane fluidity, microdomains, curvature, thickness and asymmetry but GPCRs are also regulated by specific lipid:GPCR binding, including cholesterol and anionic lipids. Understanding the molecular mechanisms whereby GPCR signalling is regulated by lipids is a very active area of research currently. A major advance in membrane protein research in recent years was the application of poly(styrene-co-maleic acid) (SMA) copolymers. These spontaneously generate SMA lipid particles (SMALPs) encapsulating membrane protein in a nano-scale disc of cell membrane, thereby removing the historical need for detergent and preserving lipid:GPCR interaction. The focus of this review is how GPCR-SMALPs are increasing our understanding of GPCR structure and function at the molecular level. Furthermore, an increasing number of 'second generation' SMA-like copolymers have been reported recently. These are reviewed from the context of increasing our understanding of GPCR molecular mechanisms. Moreover, their potential as a novel platform for downstream biophysical and structural analyses is assessed and looking ahead, the translational application of SMA-like copolymers to GPCR drug discovery programmes in the future is considered.
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Affiliation(s)
- Hoor Ayub
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK.
| | - Rebecca J Murray
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK; Department of Chemistry and Polymer Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - Gestél C Kuyler
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK; Department of Chemistry and Polymer Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | | | - Joseph Gunner
- School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - Tim R Dafforn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Bert Klumperman
- Department of Chemistry and Polymer Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - David R Poyner
- School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - Mark Wheatley
- Centre for Health and Life Sciences, Coventry University, Coventry, CV1 2DS, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
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4
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Katke C, Pedrueza-Villalmanzo E, Spustova K, Ryskulov R, Kaplan CN, Gözen I. Colony-like Protocell Superstructures. ACS NANO 2023; 17:3368-3382. [PMID: 36795609 PMCID: PMC9979656 DOI: 10.1021/acsnano.2c08093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
We report the formation, growth, and dynamics of model protocell superstructures on solid surfaces, resembling single cell colonies. These structures, consisting of several layers of lipidic compartments enveloped in a dome-shaped outer lipid bilayer, emerged as a result of spontaneous shape transformation of lipid agglomerates deposited on thin film aluminum surfaces. Collective protocell structures were observed to be mechanically more stable compared to isolated spherical compartments. We show that the model colonies encapsulate DNA and accommodate nonenzymatic, strand displacement DNA reactions. The membrane envelope is able to disassemble and expose individual daughter protocells, which can migrate and attach via nanotethers to distant surface locations, while maintaining their encapsulated contents. Some colonies feature "exocompartments", which spontaneously extend out of the enveloping bilayer, internalize DNA, and merge again with the superstructure. A continuum elastohydrodynamic theory that we developed suggests that a plausible driving force behind subcompartment formation is attractive van der Waals (vdW) interactions between the membrane and surface. The balance between membrane bending and vdW interactions yields a critical length scale of 236 nm, above which the membrane invaginations can form subcompartments. The findings support our hypotheses that in extension of the "lipid world hypothesis", protocells may have existed in the form of colonies, potentially benefiting from the increased mechanical stability provided by a superstructure.
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Affiliation(s)
- Chinmay Katke
- Department
of Physics, Virginia Polytechnic Institute
and State University, Blacksburg, Virginia 24061, United States
- Center
for Soft Matter and Biological Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Esteban Pedrueza-Villalmanzo
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Göteborg SE-412 96, Sweden
- Department
of Physics, University of Gothenburg, Universitetsplatsen 1, Gothenburg 405 30, Sweden
| | - Karolina Spustova
- Centre
for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, 0318 Oslo, Norway
| | - Ruslan Ryskulov
- Department
of Chemistry and Chemical Engineering, Chalmers
University of Technology, Göteborg SE-412 96, Sweden
| | - C. Nadir Kaplan
- Department
of Physics, Virginia Polytechnic Institute
and State University, Blacksburg, Virginia 24061, United States
- Center
for Soft Matter and Biological Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Irep Gözen
- Centre
for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, 0318 Oslo, Norway
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5
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van Walree CA. Intramolecular Hydrogen Bonding in DIBMA Model Compounds. MACROMOL THEOR SIMUL 2022. [DOI: 10.1002/mats.202200042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Cornelis A. van Walree
- Membrane Biochemistry and Biophysics Utrecht University Padualaan 8 Utrecht 3584 CH Netherlands
- University College Utrecht Campusplein 1 Utrecht 3584 ED the Netherlands
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6
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Sahoo BR, Souders CL, Watanabe-Nakayama T, Deng Z, Linton H, Suladze S, Ivanova MI, Reif B, Ando T, Martyniuk CJ, Ramamoorthy A. Conformational Tuning of Amylin by Charged Styrene-Maleic-Acid Copolymers. J Mol Biol 2022; 434:167385. [PMID: 34883118 PMCID: PMC8752516 DOI: 10.1016/j.jmb.2021.167385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 11/25/2021] [Accepted: 11/30/2021] [Indexed: 02/01/2023]
Abstract
Human amylin forms structurally heterogeneous amyloids that have been linked to type-2 diabetes. Thus, understanding the molecular interactions governing amylin aggregation can provide mechanistic insights in its pathogenic formation. Here, we demonstrate that fibril formation of amylin is altered by synthetic amphipathic copolymer derivatives of the styrene-maleic-acid (SMAQA and SMAEA). High-speed AFM is used to follow the real-time aggregation of amylin by observing the rapid formation of de novo globular oligomers and arrestment of fibrillation by the positively-charged SMAQA. We also observed an accelerated fibril formation in the presence of the negatively-charged SMAEA. These findings were further validated by fluorescence, SOFAST-HMQC, DOSY and STD NMR experiments. Conformational analysis by CD and FT-IR revealed that the SMA copolymers modulate the conformation of amylin aggregates. While the species formed with SMAQA are α-helical, the ones formed with SMAEA are rich in β-sheet structure. The interacting interfaces between SMAEA or SMAQA and amylin are mapped by NMR and microseconds all-atom MD simulation. SMAEA displayed π-π interaction with Phe23, electrostatic π-cation interaction with His18 and hydrophobic packing with Ala13 and Val17; whereas SMAQA showed a selective interaction with amylin's C terminus (residues 31-37) that belongs to one of the two β-sheet regions (residues 14-19 and 31-36) involved in amylin fibrillation. Toxicity analysis showed both SMA copolymers to be non-toxic in vitro and the amylin species formed with the copolymers showed minimal deformity to zebrafish embryos. Together, this study demonstrates that chemical tools, such as copolymers, can be used to modulate amylin aggregation, alter the conformation of species.
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Affiliation(s)
- Bikash R Sahoo
- Biophysics Program, The University of Michigan, Ann Arbor, MI 48109, USA; Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, The University of Michigan, Ann Arbor, MI 48109, USA
| | | | | | - Zhou Deng
- Biophysics Program, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Hunter Linton
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Saba Suladze
- Department of Chemistry, Technische Universität München, Garching 85748, Germany
| | - Magdalena I Ivanova
- Biophysics Program, The University of Michigan, Ann Arbor, MI 48109, USA; Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Bernd Reif
- Department of Chemistry, Technische Universität München, Garching 85748, Germany
| | - Toshio Ando
- Bio-AFM Frontier Research Center, Kanazawa University, Kanazawa 9201192, Japan
| | - Christopher J Martyniuk
- Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, The University of Michigan, Ann Arbor, MI 48109, USA; Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, The University of Michigan, Ann Arbor, MI 48109, USA.
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7
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Orekhov PS, Bozdaganyan ME, Voskoboynikova N, Mulkidjanian AY, Karlova MG, Yudenko A, Remeeva A, Ryzhykau YL, Gushchin I, Gordeliy VI, Sokolova OS, Steinhoff HJ, Kirpichnikov MP, Shaitan KV. Mechanisms of Formation, Structure, and Dynamics of Lipoprotein Discs Stabilized by Amphiphilic Copolymers: A Comprehensive Review. NANOMATERIALS 2022; 12:nano12030361. [PMID: 35159706 PMCID: PMC8838559 DOI: 10.3390/nano12030361] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/15/2022] [Accepted: 01/20/2022] [Indexed: 12/16/2022]
Abstract
Amphiphilic copolymers consisting of alternating hydrophilic and hydrophobic units account for a major recent methodical breakthrough in the investigations of membrane proteins. Styrene–maleic acid (SMA), diisobutylene–maleic acid (DIBMA), and related copolymers have been shown to extract membrane proteins directly from lipid membranes without the need for classical detergents. Within the particular experimental setup, they form disc-shaped nanoparticles with a narrow size distribution, which serve as a suitable platform for diverse kinds of spectroscopy and other biophysical techniques that require relatively small, homogeneous, water-soluble particles of separate membrane proteins in their native lipid environment. In recent years, copolymer-encased nanolipoparticles have been proven as suitable protein carriers for various structural biology applications, including cryo-electron microscopy (cryo-EM), small-angle scattering, and conventional and single-molecule X-ray diffraction experiments. Here, we review the current understanding of how such nanolipoparticles are formed and organized at the molecular level with an emphasis on their chemical diversity and factors affecting their size and solubilization efficiency.
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Affiliation(s)
- Philipp S. Orekhov
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia; (M.E.B.); (M.G.K.); (O.S.S.); (M.P.K.)
- Faculty of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
- Institute of Personalized Medicine, Sechenov University, 119146 Moscow, Russia
- Correspondence: (P.S.O.); (K.V.S.)
| | - Marine E. Bozdaganyan
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia; (M.E.B.); (M.G.K.); (O.S.S.); (M.P.K.)
- Faculty of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Natalia Voskoboynikova
- Department of Physics, University of Osnabrück, Barbarastrasse 7, 49076 Osnabrück, Germany; (N.V.); (A.Y.M.); (H.-J.S.)
| | - Armen Y. Mulkidjanian
- Department of Physics, University of Osnabrück, Barbarastrasse 7, 49076 Osnabrück, Germany; (N.V.); (A.Y.M.); (H.-J.S.)
- Faculty of Bioengineering and Bioinformatics and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Maria G. Karlova
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia; (M.E.B.); (M.G.K.); (O.S.S.); (M.P.K.)
| | - Anna Yudenko
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (A.Y.); (A.R.); (Y.L.R.); (I.G.); (V.I.G.)
| | - Alina Remeeva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (A.Y.); (A.R.); (Y.L.R.); (I.G.); (V.I.G.)
| | - Yury L. Ryzhykau
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (A.Y.); (A.R.); (Y.L.R.); (I.G.); (V.I.G.)
| | - Ivan Gushchin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (A.Y.); (A.R.); (Y.L.R.); (I.G.); (V.I.G.)
| | - Valentin I. Gordeliy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (A.Y.); (A.R.); (Y.L.R.); (I.G.); (V.I.G.)
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, 52428 Jülich, Germany
- Institut de Biologie Structurale J.-P. Ebel, Université Grenoble Alpes-CEA-CNRS, 38000 Grenoble, France
- JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Olga S. Sokolova
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia; (M.E.B.); (M.G.K.); (O.S.S.); (M.P.K.)
- Faculty of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
| | - Heinz-Jürgen Steinhoff
- Department of Physics, University of Osnabrück, Barbarastrasse 7, 49076 Osnabrück, Germany; (N.V.); (A.Y.M.); (H.-J.S.)
| | - Mikhail P. Kirpichnikov
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia; (M.E.B.); (M.G.K.); (O.S.S.); (M.P.K.)
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Konstantin V. Shaitan
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia; (M.E.B.); (M.G.K.); (O.S.S.); (M.P.K.)
- Correspondence: (P.S.O.); (K.V.S.)
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8
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Caparotta M, Puiatti M, Masone D. Artificial stabilization of the fusion pore by intra-organelle styrene-maleic acid copolymers. SOFT MATTER 2021; 17:8314-8321. [PMID: 34550159 DOI: 10.1039/d1sm00978h] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Styrene-maleic acid copolymers have become an advantageous detergent-free alternative for membrane protein isolation. Since their discovery, experimental membrane protein extraction and purification by keeping intact their lipid environment has become significantly easier. With the aim of identifying new applications of these interesting copolymers, their molecular binding and functioning mechanisms have recently become intense objects of study. In this work, we describe the use of styrene-maleic acid copolymers as an artificial tool to stabilize the fusion pore. We show that when these copolymers circumscribe the water channel that defines the fusion pore, they keep it from shrinking and closing. We describe how only intra-organelle copolymers have stabilizing capabilities while extra-organelle ones have negligible or even contrary effects on the fusion pore life-time.
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Affiliation(s)
- Marcelo Caparotta
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina
| | - Marcelo Puiatti
- Instituto de Investigaciones en Físico-Química de Córdoba (INFIQC) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba (UNC), 5016, Córdoba, Argentina
| | - Diego Masone
- Facultad de Ingeniería, Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina
- Instituto de Histología y Embriología de Mendoza (IHEM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina.
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9
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Esmaili M, Eldeeb MA, Moosavi-Movahedi AA. Current Developments in Native Nanometric Discoidal Membrane Bilayer Formed by Amphipathic Polymers. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1771. [PMID: 34361157 PMCID: PMC8308186 DOI: 10.3390/nano11071771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/27/2021] [Accepted: 06/30/2021] [Indexed: 12/18/2022]
Abstract
Unlike cytosolic proteins, membrane proteins (MPs) are embedded within the plasma membrane and the lipid bilayer of intracellular organelles. MPs serve in various cellular processes and account for over 65% of the current drug targets. The development of membrane mimetic systems such as bicelles, short synthetic polymers or amphipols, and membrane scaffold proteins (MSP)-based nanodiscs has facilitated the accommodation of synthetic lipids to stabilize MPs, yet the preparation of these membrane mimetics remains detergent-dependent. Bio-inspired synthetic polymers present an invaluable tool for excision and liberation of superstructures of MPs and their surrounding annular lipid bilayer in the nanometric discoidal assemblies. In this article, we discuss the significance of self-assembling process in design of biomimetic systems, review development of multiple series of amphipathic polymers and the significance of these polymeric "belts" in biomedical research in particular in unraveling the structures, dynamics and functions of several high-value membrane protein targets.
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Affiliation(s)
- Mansoore Esmaili
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Mohamed A. Eldeeb
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada;
- Department of Chemistry, Faculty of Science, Cairo University, Cairo 12613, Egypt
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10
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Durairaju P, Umarani C, Rajabather JR, Alanazi AM, Periyasami G, Wilson LD. Synthesis and Characterization of Pyridine-Grafted Copolymers of Acrylic Acid-Styrene Derivatives for Antimicrobial and Fluorescence Applications. MICROMACHINES 2021; 12:672. [PMID: 34201351 PMCID: PMC8230187 DOI: 10.3390/mi12060672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 11/16/2022]
Abstract
The goal of the present study was to copolymerize 3-(4-acetylphenylcarbamoyl) acrylic acid and styrene using azo-bis-isobutyronitrile (AIBN) as a catalyst. The resulting copolymers exhibited number average molecular weights (Mn) of 3.73-5.23 × 104 g/mol with a variable polydispersity (PDI = 2.3-3.8). The amide group of the PMA/PSA polymer was used for grafting poly (-styrene-maleic acid substituted aromatic 2-aminopyridine) by the Hantzsch reaction using a substituted aromatic aldehyde, malononitrile, and ammonium acetate. The polymer can emit strong blue fluorescence (λ = 510 nm) and its thermal stability and solubility were enhanced by polymer grafting. Moreover, the polymer showed the fluorescence spectra of the copolymer had a strong, broad emission band between 300 to 550 nm (maximum wavelength 538 nm) under excitation at 293 nm. The Hantzsch reaction yields an interesting class of nitrogen-based heterocycles that combine with a synthetic strategy for synthesis of grafted co-polymer pyridine-styrene derivatives. The as-prepared pyridine-based polymer compounds were screened against Gram-positive and Gram-negative bacteria, where a maximum inhibition zone toward all four types of bacteria was observed, including specific antifungal activity. Herein, a series of pyridine compounds were synthesized that showed enhanced fluorescent properties and antimicrobial properties due to their unique structure and ability to form polymer assemblies.
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Affiliation(s)
- Periyan Durairaju
- Department of Chemistry, Thiruvalluvar Government Arts College, Rasipuram 636007, Tamilnadu, India
- Department of Chemistry, Government Arts College (Autonomous), Salem 636007, Tamilnadu, India;
| | - Chinnasamy Umarani
- Department of Chemistry, Government Arts College (Autonomous), Salem 636007, Tamilnadu, India;
| | - Jothi Ramalingam Rajabather
- Chemistry Department, College of Sciences, King Saud University, Riyadh 11451, Saudi Arabia; (J.R.R.); (G.P.)
| | - Amer M. Alanazi
- Pharmaceutical Chemistry Department, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia;
| | - Govindasami Periyasami
- Chemistry Department, College of Sciences, King Saud University, Riyadh 11451, Saudi Arabia; (J.R.R.); (G.P.)
| | - Lee D. Wilson
- Department of Chemistry, University of Saskatchewan, 110 Science Place—Room 165 Thorvaldson Bldg., Saskatoon, SK S7N 5C9, Canada
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11
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Bjørnestad V, Orwick-Rydmark M, Lund R. Understanding the Structural Pathways for Lipid Nanodisc Formation: How Styrene Maleic Acid Copolymers Induce Membrane Fracture and Disc Formation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:6178-6188. [PMID: 33979520 PMCID: PMC8280715 DOI: 10.1021/acs.langmuir.1c00304] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/28/2021] [Indexed: 06/12/2023]
Abstract
Lipid nanodiscs formed by mixtures of styrene maleic acid (SMA) copolymers and lipid membranes are important tools for studying membrane proteins in many biotechnological applications. However, molecular interactions leading up to their formation are not well understood. Here, we elucidate the nanodisc formation pathways for SMA/lipid vesicle mixtures using small-angle X-ray scattering (SAXS) that allows detailed in situ nanostructural information. SMA copolymer that is initially aggregated in solution inserts its styrene units into the lipid bilayer hydrocarbon region, leading to fractures in the membrane. The initial copolymer-lipid interactions observed in the vesicles are also present in the formed discs, with excess copolymer distributed along the normal of the bilayer. The size and SMA distribution in the resulting discs strongly depend on the temperature, lipid/copolymer ratio, and lipid type. We find that the solubilization limit increases for membranes above the melting point, suggesting that defects in gel-like lipid membranes play a significant role in membrane fracturing and nanodisc formation. These findings provide unique insights into the formation of nanodiscs as well as into the microscopic mechanism of solubilization, which plays an important role in many applications and products ranging from household goods to biotechnology and medicine.
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Affiliation(s)
| | | | - Reidar Lund
- Department
of Chemistry, University of Oslo, Sem Sælandsvei 26, 0371 Oslo, Norway
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12
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Krajewska M, Koprowski P. Solubilization, purification, and functional reconstitution of human ROMK potassium channel in copolymer styrene-maleic acid (SMA) nanodiscs. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183555. [PMID: 33444624 DOI: 10.1016/j.bbamem.2021.183555] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/13/2020] [Accepted: 01/04/2021] [Indexed: 12/18/2022]
Abstract
Expression, purification, and functional reconstitution of mammalian ion channels are often challenging. Heterologous expression of mammalian channels in bacteria can be advantageous due to unrelated protein environment and the lack of risk of copurification of endogenous proteins, e.g., accessory channel subunits that can influence the channel activity. Also, direct recording of channel activity could be challenging due to their intracellular localization like in the case of mitochondrial channels. The activity of purified channels can be characterized at the single-molecule level by electrophysiological techniques, such as planar lipid bilayers (PLB). In this work, we describe a simple approach to accomplish PLB recording of the activity of single renal outer medullary potassium channels ROMK expressed in E. coli. We focused on the ROMK2 isoform that is present at low levels in the mitochondria and can be responsible for mitoKATP activity. We screened for the best construct to express the codon-optimized ROMK proteins with a 6xHis tag for protein purification. The strategy involved the use of optimal styrene-maleic acid (SMA) copolymer, which forms so-called polymer nanodiscs, to solubilize and purify ROMK-containing SMA lipid particles (SMALPs), which were amenable for fusion with PLB. Reconstituted ROMK channels exhibited ion selectivity, rectification, and pharmacological properties, which are in agreement with previous work on ROMK channels.
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Affiliation(s)
- Milena Krajewska
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology PAS, Pasteur str. 3, Warsaw 02-093, Poland
| | - Piotr Koprowski
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology PAS, Pasteur str. 3, Warsaw 02-093, Poland.
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13
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Ball LE, Riley LJ, Hadasha W, Pfukwa R, Smith CJI, Dafforn TR, Klumperman B. Influence of DIBMA Polymer Length on Lipid Nanodisc Formation and Membrane Protein Extraction. Biomacromolecules 2020; 22:763-772. [PMID: 33373193 DOI: 10.1021/acs.biomac.0c01538] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Polymer-based lipid nanoparticles like styrene-maleic acid lipid particles have revolutionized the study of membrane proteins. More recently, alternative polymers such as poly(diisobutylene-alt-maleic acid) (DIBMA) have been used in this field. DIBMA is commonly synthesized via conventional radical copolymerization. In order to study the influence of its chain length on lipid nanodisc formation and membrane protein extraction, we synthesized DIBMA with molar masses varying from 1.2-12 kDa via RAFT-mediated polymerization. For molar masses in the range of 3-7 kDa, the rate of lipid nanodisc formation was the highest and similar to those of poly(styrene-co-maleic acid) (SMA) and commercially available DIBMA. ZipA solubilization efficiency was significantly higher than for commercially available DIBMA and similar to SMA (circa 75%). Furthermore, RAFT-made DIBMA with a molar mass of 1.2-3.9 kDa showed a much cleaner separation on SDS-PAGE, without the smearing that is typically seen for SMA and commercially available DIBMA.
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Affiliation(s)
- Lauren E Ball
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Liam J Riley
- School of Life Sciences, The University of Warwick, Gibbet Hill Campus, Coventry CV4 7AL, United Kingdom.,School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Waled Hadasha
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Rueben Pfukwa
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Corinne J I Smith
- School of Life Sciences, The University of Warwick, Gibbet Hill Campus, Coventry CV4 7AL, United Kingdom
| | - Timothy R Dafforn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Bert Klumperman
- Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
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Generating therapeutic monoclonal antibodies to complex multi-spanning membrane targets: Overcoming the antigen challenge and enabling discovery strategies. Methods 2020; 180:111-126. [PMID: 32422249 DOI: 10.1016/j.ymeth.2020.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/21/2020] [Accepted: 05/13/2020] [Indexed: 12/17/2022] Open
Abstract
Complex integral membrane proteins, which are embedded in the cell surface lipid bilayer by multiple transmembrane spanning helices, encompass families of proteins which are important target classes for drug discovery. These protein families include G protein-coupled receptors, ion channels and transporters. Although these proteins have typically been targeted by small molecule drugs and peptides, the high specificity of monoclonal antibodies offers a significant opportunity to selectively modulate these target proteins. However, it remains the case that isolation of antibodies with desired pharmacological function(s) has proven difficult due to technical challenges in preparing membrane protein antigens suitable to support antibody drug discovery. In this review recent progress in defining strategies for generation of membrane protein antigens is outlined. We also highlight antibody isolation strategies which have generated antibodies which bind the membrane protein and modulate the protein function.
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