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Lethcoe K, Fox CA, Ryan RO. Foam fractionation of a recombinant biosurfactant apolipoprotein. J Biotechnol 2022; 343:25-31. [PMID: 34808251 PMCID: PMC8714704 DOI: 10.1016/j.jbiotec.2021.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/10/2021] [Accepted: 11/13/2021] [Indexed: 01/12/2023]
Abstract
Locusta migratoria apolipophorin III (apoLp-III) possesses the ability to exist as a water soluble amphipathic α-helix bundle and a lipid surface seeking apolipoprotein. The intrinsic ability of apoLp-III to transform phospholipid vesicles into reconstituted discoidal high-density lipoproteins (rHDL) has led to myriad applications. To improve the yield of recombinant apoLp-III, studies were performed in a bioreactor. Induction of apoLp-III expression generated a protein product that is secreted from E. coli into the culture medium. Interaction of apoLp-III with gas and liquid components in media produced large quantities of thick foam. A continuous foam fractionation process yielded a foamate containing apoLp-III as the sole major protein component. The yield of recombinant apoLp-III was ~0.2 g / liter bacterial culture. Mass spectrometry analysis verified the identity of the target protein and indicated no modifications or changes to apoLp-III occurred as a result of foam fractionation. The functional ability of apoLp-III to induce rHDL formation was evaluated by incubating foam fractionated apoLp-III with phosphatidylcholine vesicles. FPLC size exclusion chromatography revealed a single major population of particles in the size range of rHDL. The results described offer a novel approach to bioreactor-based apoLp-III production that takes advantage of its intrinsic biosurfactant properties.
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Affiliation(s)
- Kyle Lethcoe
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Reno, NV 89557, USA
| | - Colin A Fox
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Reno, NV 89557, USA
| | - Robert O Ryan
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Reno, NV 89557, USA.
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2
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Kopf AH, Lijding O, Elenbaas BOW, Koorengevel MC, Dobruchowska JM, van Walree CA, Killian JA. Synthesis and Evaluation of a Library of Alternating Amphipathic Copolymers to Solubilize and Study Membrane Proteins. Biomacromolecules 2022; 23:743-759. [PMID: 34994549 PMCID: PMC8924871 DOI: 10.1021/acs.biomac.1c01166] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
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Amphipathic copolymers
such as poly(styrene-maleic acid) (SMA)
are promising tools for the facile extraction of membrane proteins
(MPs) into native nanodiscs. Here, we designed and synthesized a library
of well-defined alternating copolymers of SMA analogues in order to
elucidate polymer properties that are important for MP solubilization
and stability. MP extraction efficiency was determined using KcsA
from E. coli membranes, and general solubilization
efficiency was investigated via turbidimetry experiments on membranes
of E. coli, yeast mitochondria, and synthetic
lipids. Remarkably, halogenation of SMA copolymers dramatically improved
solubilization efficiency in all systems, while substituents on the
copolymer backbone improved resistance to Ca2+. Relevant
polymer properties were found to include hydrophobic balance, size
and positioning of substituents, rigidity, and electronic effects.
The library thus contributes to the rational design of copolymers
for the study of MPs.
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Affiliation(s)
- Adrian H Kopf
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Odette Lijding
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Barend O W Elenbaas
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Martijn C Koorengevel
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Justyna M Dobruchowska
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, and Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Cornelis A van Walree
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - J Antoinette Killian
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
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3
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Fox CA, Moschetti A, Ryan RO. Reconstituted HDL as a therapeutic delivery device. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159025. [PMID: 34375767 DOI: 10.1016/j.bbalip.2021.159025] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/09/2021] [Accepted: 07/25/2021] [Indexed: 12/27/2022]
Abstract
Studies of "pre β" high density lipoprotein (HDL) and reconstituted HDL (rHDL) have contributed to our understanding of the Reverse Cholesterol Transport pathway. The relative ease with which discoidal rHDL can be generated in vitro has led to novel applications including a) infusion of rHDL into patients to promote regression of atherosclerosis; b) use of rHDL as a miniature membrane for integration of transmembrane proteins in a native-like conformation and c) incorporation of hydrophobic bioactive molecules into rHDL, creating a delivery device. The present review is focused on bioactive agent containing rHDL. The broad array of hydrophobic bioactive molecules successfully incorporated into these particles is discussed, as well as the use of natural lipids and synthetic lipid analogs to confer distinctive binding activity. This technology remains in its infancy with the full potential of these simple, yet elegant, nanoparticles still to be discovered.
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Affiliation(s)
- Colin A Fox
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Reno, NV 89557, United States of America
| | - Anthony Moschetti
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Reno, NV 89557, United States of America
| | - Robert O Ryan
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Reno, NV 89557, United States of America.
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4
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Mirheydari M, Putta P, Mann EK, Kooijman EE. Interaction of Two Amphipathic α-Helix Bundle Proteins, ApoLp-III and ApoE 3, with the Oil-Aqueous Interface. J Phys Chem B 2021; 125:4746-4756. [PMID: 33939404 DOI: 10.1021/acs.jpcb.1c00271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Protein-lipid interactions govern the structure and function of lipoprotein particles, which transport neutral lipids and other hydrophobic cargo through the blood stream. Apolipoproteins cover the surface of lipoprotein particles, including low-density (LDL) and high-density (HDL) lipoproteins, and determine their function. Previous work has focused on small peptides derived from these apolipoproteins or used such artificial lipid systems as Langmuir monolayers or the lipid disc assay to determine how apolipoproteins interact with the neutral lipid interface. Here, we focus on a recurring protein domain found in many neutral lipid-binding proteins, the amphipathic α-helix bundle. We use liquid droplet tensiometry to investigate protein-lipid interactions on an oil droplet, which mimics the real lipoprotein interface. The N-terminus of apoE 3 and full-length apoLp-III serve as model proteins. We find that each protein interacts with lipid monolayers at the oil-aqueous interface in unique ways. For the first time, we show that helix bundle unfolding is critical for proper protein insertion into the lipid monolayer at the oil-aqueous interface and that specific membrane lipids promote the rebinding of protein upon fluctuation in droplet size. These results shed new light on how amphipathic apolipoprotein α-helix bundles interact with neutral lipid particles.
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5
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Peng Y, Kelle R, Little C, Michonova E, Kornev KG, Alexov E. pH-Dependent Interactions of Apolipophorin-III with a Lipid Disk. J Comput Biophys Chem 2021. [DOI: 10.1142/s2737416520420041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Apolipophorin-III (ApoLp-III) is required for stabilization of molecular shuttles of lipid fuels in insects and is found to contribute to the insect immune reaction. Rearrangement of its five [Formula: see text]-helices enables ApoLp-III to reversibly associate with lipids. We investigate computationally the conformational changes of ApoLp-III and the pH-dependence of the binding free energy of ApoLp-III association with a lipid disk. A dominant binding mode along with several minor, low population, modes of the ApoLp-III binding to a lipid disk was identified. The pH-dependence of the binding energy for ApoLp-III with the lipid disk is predicted to be significant, with the pH-optimum at pH[Formula: see text]. The calculations suggest that there are no direct interactions between the lipid head groups and titratable residues of ApoLp-III. In the physiological pH range from 6.0 to 9.0, the binding free energy of ApoLp-III with the lipid disk decreases significantly with respect to its optimal value at pH 8.0 (at pH[Formula: see text], it is 1.02[Formula: see text]kcal/mol and at pH[Formula: see text] it is 0.23[Formula: see text]kcal/mol less favorable than at the optimal pH[Formula: see text]), indicating that the pH is an important regulator of ApoLp-III lipid disk association.
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Affiliation(s)
- Yunhui Peng
- Department of Physics and Astronomy, College of Sciences, Clemson University, Clemson, SC 29634, USA
| | - Rudolfs Kelle
- Department of Physics and Astronomy, College of Sciences, Clemson University, Clemson, SC 29634, USA
- Department of Chemistry, Erskine College, Due West, SC 29639, USA
| | - Chandler Little
- Department of Physics and Astronomy, College of Sciences, Clemson University, Clemson, SC 29634, USA
- Department of Chemistry, Erskine College, Due West, SC 29639, USA
| | | | - Kostantin G. Kornev
- Department of Material Sciences and Engineering, Clemson University, Clemson, SC 29634, USA
| | - Emil Alexov
- Department of Physics and Astronomy, College of Sciences, Clemson University, Clemson, SC 29634, USA
- Department of Material Sciences and Engineering, Clemson University, Clemson, SC 29634, USA
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6
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Maravilla E, Le DP, Tran JJ, Chiu MH, Prenner EJ, Weers PM. Apolipophorin III interaction with phosphatidylglycerol and lipopolysaccharide: A potential mechanism for antimicrobial activity. Chem Phys Lipids 2020; 229:104909. [DOI: 10.1016/j.chemphyslip.2020.104909] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 03/18/2020] [Accepted: 03/18/2020] [Indexed: 01/27/2023]
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7
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Chuang ST, Cruz S, Narayanaswami V. Reconfiguring Nature's Cholesterol Accepting Lipoproteins as Nanoparticle Platforms for Transport and Delivery of Therapeutic and Imaging Agents. Nanomaterials (Basel) 2020; 10:E906. [PMID: 32397159 PMCID: PMC7279153 DOI: 10.3390/nano10050906] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 12/13/2022]
Abstract
Apolipoproteins are critical structural and functional components of lipoproteins, which are large supramolecular assemblies composed predominantly of lipids and proteins, and other biomolecules such as nucleic acids. A signature feature of apolipoproteins is the preponderance of amphipathic α-helical motifs that dictate their ability to make extensive non-covalent inter- or intra-molecular helix-helix interactions in lipid-free states or helix-lipid interactions with hydrophobic biomolecules in lipid-associated states. This review focuses on the latter ability of apolipoproteins, which has been capitalized on to reconstitute synthetic nanoscale binary/ternary lipoprotein complexes composed of apolipoproteins/peptides and lipids that mimic native high-density lipoproteins (HDLs) with the goal to transport drugs. It traces the historical development of our understanding of these nanostructures and how the cholesterol accepting property of HDL has been reconfigured to develop them as drug-loading platforms. The review provides the structural perspective of these platforms with different types of apolipoproteins and an overview of their synthesis. It also examines the cargo that have been loaded into the core for therapeutic and imaging purposes. Finally, it lays out the merits and challenges associated with apolipoprotein-based nanostructures with a future perspective calling for a need to develop "zip-code"-based delivery for therapeutic and diagnostic applications.
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Affiliation(s)
| | | | - Vasanthy Narayanaswami
- Department of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Blvd, Long Beach, CA 90840, USA; (S.T.C.); (S.C.)
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8
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Fukuda R, Saito M, Shibukawa S, Sumino A, Nakano M, Murakami T. Urea-Assisted Reconstitution of Discoidal High-Density Lipoprotein. Biochemistry 2020; 59:1455-1464. [DOI: 10.1021/acs.biochem.0c00075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Ryosuke Fukuda
- Department of Biotechnology, Graduate School of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Mio Saito
- Department of Biotechnology, Graduate School of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Shiori Shibukawa
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Ayumi Sumino
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan
| | - Minoru Nakano
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Toyama 930-0194, Japan
| | - Tatsuya Murakami
- Department of Biotechnology, Graduate School of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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9
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Augustyn B, Stepien P, Poojari C, Mobarak E, Polit A, Wisniewska-Becker A, Róg T. Cholesteryl Hemisuccinate Is Not a Good Replacement for Cholesterol in Lipid Nanodiscs. J Phys Chem B 2019; 123:9839-9845. [DOI: 10.1021/acs.jpcb.9b07853] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
| | - Piotr Stepien
- Bionanoscience and Biochemistry Laboratory, Malopolska Centre of Biotechnology, Jagiellonian University, Gronostajowa 7A, 30-387 Krakow, Poland
| | - Chetan Poojari
- Department of Physics, Faculty of Science, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Theoretical Physics and Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany
| | - Edouard Mobarak
- Department of Physics, Faculty of Science, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | | | | | - Tomasz Róg
- Department of Physics, Faculty of Science, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
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10
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Patel H, Ding B, Ernst K, Shen L, Yuan W, Tang J, Drake LR, Kang J, Li Y, Chen Z, Schwendeman A. Characterization of apolipoprotein A-I peptide phospholipid interaction and its effect on HDL nanodisc assembly. Int J Nanomedicine 2019; 14:3069-3086. [PMID: 31118623 PMCID: PMC6500440 DOI: 10.2147/ijn.s179837] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 03/06/2019] [Indexed: 11/23/2022] Open
Abstract
Background: Synthetic HDLs (sHDLs), small nanodiscs of apolipoprotein mimetic peptides surrounding lipid bilayers, were developed clinically for atheroma regression in cardiovascular patients. Formation of HDL involves interaction of apolipoprotein A-I (ApoA-I) with phospholipid bilayers and assembly into lipid-protein nanodiscs. Purpose: The objective of this study is to improve understanding of physico-chemical aspects of HDL biogenesis such as the thermodynamics of ApoA-I-peptide membrane insertion, lipid binding, and HDL self-assembly to improve our ability to form homogeneous sHDL nanodiscs that are suitable for clinical administration. Methods: The ApoA-I-mimetic peptide, 22A, was combined with either egg sphingomyelin (eSM) or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) phospholipid vesicles to form sHDL. The sHDL assembly process was investigated through lipid vehicle solubilization assays and characterization of purity, size, and morphology of resulting nanoparticles via gel permeation chromatography (GPC), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Peptide-lipid interactions involved were further probed by sum frequency generation (SFG) vibrational spectroscopy and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). The pharmacokinetics of eSM-sHDL and POPC-sHDL nanodiscs were investigated in Sprague Dawley rats. Results: sHDL formation was temperature-dependent, with spontaneous formation of sHDL nanoparticles occurring only at temperatures exceeding lipid transition temperatures as evidenced by DLS, GPC, and TEM characterization. SFG and ATR-FTIR spectroscopy findings support a change in peptide-lipid bilayer interactions at temperatures above the lipid transition temperature. Lipid-22A interactions were stronger with eSM than with POPC, which resulted in the formation of more homogeneous sHDL nanoparticles with longer in vivo circulation time as evidenced the PK study. Conclusion: Physico-chemical characteristics of sHDL are in part determined by phospholipid composition. Optimization of phospholipid composition may be utilized to improve the stability and homogeneity of sHDL.
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Affiliation(s)
- Hiren Patel
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Bei Ding
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Kelsey Ernst
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Lei Shen
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Wenmin Yuan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Jie Tang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Lindsey R Drake
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Jukyung Kang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Yaoxin Li
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Zhan Chen
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Anna Schwendeman
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, USA
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11
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Mirheydari M, Mann EK, Kooijman EE. Interaction of a model apolipoprotein, apoLp-III, with an oil-phospholipid interface. Biochim Biophys Acta Biomembr 2017; 1860:396-406. [PMID: 29030246 DOI: 10.1016/j.bbamem.2017.10.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 09/22/2017] [Accepted: 10/08/2017] [Indexed: 01/29/2023]
Abstract
Lipid droplets are "small" organelles that play an important role in de novo synthesis of new membrane, and steroid hormones, as well as in energy storage. The way proteins interact specifically with the oil-(phospho-)lipid monolayer interface of lipid droplets is a relatively unexplored but crucial question. Here, we use our home built liquid droplet tensiometer to mimic intracellular lipid droplets and study protein-lipid interactions at this interface. As model neutral lipid binding protein, we use apoLp-III, an amphipathic α-helix bundle protein. This domain is also found in proteins from the perilipin family and in apoE. Protein binding to the monolayer is studied by the decrease in the oil/water surface tension. Previous work used POPC (one of the major lipids found on lipid droplets) to form the phospholipid monolayer on the triolein surface. Here we expand this work by incorporating other lipids with different physico-chemical properties to study the effect of charge and lipid head-group size. This study sheds light on the affinity of this important protein domain to interact with lipids.
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Affiliation(s)
- Mona Mirheydari
- Physics Department, Kent State University, Kent, OH 44242, United States.
| | - Elizabeth K Mann
- Physics Department, Kent State University, Kent, OH 44242, United States
| | - Edgar E Kooijman
- Department of Biological Sciences, Kent State University, Kent, OH 44242, United States
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12
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Horn JVC, Ellena RA, Tran JJ, Beck WHJ, Narayanaswami V, Weers PMM. Transfer of C-terminal residues of human apolipoprotein A-I to insect apolipophorin III creates a two-domain chimeric protein with enhanced lipid binding activity. Biochim Biophys Acta Biomembr 2017; 1859:1317-1325. [PMID: 28434970 DOI: 10.1016/j.bbamem.2017.04.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 04/14/2017] [Accepted: 04/19/2017] [Indexed: 01/11/2023]
Abstract
Apolipophorin III (apoLp-III) is an insect apolipoprotein (18kDa) that comprises a single five-helix bundle domain. In contrast, human apolipoprotein A-I (apoA-I) is a 28kDa two-domain protein: an α-helical N-terminal domain (residues 1-189) and a less structured C-terminal domain (residues 190-243). To better understand the apolipoprotein domain organization, a novel chimeric protein was engineered by attaching residues 179 to 243 of apoA-I to the C-terminal end of apoLp-III. The apoLp-III/apoA-I chimera was successfully expressed and purified in E. coli. Western blot analysis and mass spectrometry confirmed the presence of the C-terminal domain of apoA-I within the chimera. While parent apoLp-III did not self-associate, the chimera formed oligomers similar to apoA-I. The chimera displayed a lower α-helical content, but the stability remained similar compared to apoLp-III, consistent with the addition of a less structured domain. The chimera was able to solubilize phospholipid vesicles at a significantly higher rate compared to apoLp-III, approaching that of apoA-I. The chimera was more effective in protecting phospholipase C-treated low density lipoprotein from aggregation compared to apoLp-III. In addition, binding interaction of the chimera with phosphatidylglycerol vesicles and lipopolysaccharides was considerably improved compared to apoLp-III. Thus, addition of the C-terminal domain of apoA-I to apoLp-III created a two-domain protein, with self-association, lipid and lipopolysaccharide binding properties similar to apoA-I. The apoA-I like behavior of the chimera indicate that these properties are independent from residues residing in the N-terminal domain of apoA-I, and that they can be transferred from apoA-I to apoLp-III.
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Affiliation(s)
- James V C Horn
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, United States
| | - Rachel A Ellena
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, United States
| | - Jesse J Tran
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, United States
| | - Wendy H J Beck
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, United States
| | - Vasanthy Narayanaswami
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, United States
| | - Paul M M Weers
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, United States.
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13
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Dominguez Pardo JJ, Dörr JM, Iyer A, Cox RC, Scheidelaar S, Koorengevel MC, Subramaniam V, Killian JA. Solubilization of lipids and lipid phases by the styrene-maleic acid copolymer. Eur Biophys J 2017; 46:91-101. [PMID: 27815573 PMCID: PMC5209432 DOI: 10.1007/s00249-016-1181-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 10/11/2016] [Indexed: 10/27/2022]
Abstract
A promising tool in membrane research is the use of the styrene-maleic acid (SMA) copolymer to solubilize membranes in the form of nanodiscs. Since membranes are heterogeneous in composition, it is important to know whether SMA thereby has a preference for solubilization of either specific types of lipids or specific bilayer phases. Here, we investigated this by performing partial solubilization of model membranes and analyzing the lipid composition of the solubilized fraction. We found that SMA displays no significant lipid preference in homogeneous binary lipid mixtures in the fluid phase, even when using lipids that by themselves show very different solubilization kinetics. By contrast, in heterogeneous phase-separated bilayers, SMA was found to have a strong preference for solubilization of lipids in the fluid phase as compared to those in either a gel phase or a liquid-ordered phase. Together the results suggest that (1) SMA is a reliable tool to characterize native interactions between membrane constituents, (2) any solubilization preference of SMA is not due to properties of individual lipids but rather due to properties of the membrane or membrane domains in which these lipids reside and (3) exploiting SMA resistance rather than detergent resistance may be an attractive approach for the isolation of ordered domains from biological membranes.
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Affiliation(s)
- Juan J Dominguez Pardo
- Department of Chemistry, Faculty of Science, Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Padualaan 8, 3584, Utrecht, The Netherlands.
| | - Jonas M Dörr
- Department of Chemistry, Faculty of Science, Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Padualaan 8, 3584, Utrecht, The Netherlands
| | - Aditya Iyer
- Nanoscale Biophysics Group, FOM Institute AMOLF, Science Park 104, 1098, Amsterdam, The Netherlands
| | - Ruud C Cox
- Department of Chemistry, Faculty of Science, Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Padualaan 8, 3584, Utrecht, The Netherlands
| | - Stefan Scheidelaar
- Department of Chemistry, Faculty of Science, Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Padualaan 8, 3584, Utrecht, The Netherlands
| | - Martijn C Koorengevel
- Department of Chemistry, Faculty of Science, Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Padualaan 8, 3584, Utrecht, The Netherlands
| | - Vinod Subramaniam
- Nanoscale Biophysics Group, FOM Institute AMOLF, Science Park 104, 1098, Amsterdam, The Netherlands
- Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081, Amsterdam, The Netherlands
| | - J Antoinette Killian
- Department of Chemistry, Faculty of Science, Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research, Padualaan 8, 3584, Utrecht, The Netherlands.
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14
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Dwivedi P, Rodriguez J, Ibe NU, Weers PMM. Deletion of the N- or C-Terminal Helix of Apolipophorin III To Create a Four-Helix Bundle Protein. Biochemistry 2016; 55:3607-15. [PMID: 27280697 DOI: 10.1021/acs.biochem.6b00381] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Apolipophorin III (apoLp-III) is an exchangeable apolipoprotein found in insects and plays an important function in lipid transport. The protein has an unusual five-helix bundle architecture, deviating from the common four-helix bundle motif. To understand the role of the additional helix in apoLp-III, the N-terminal or C-terminal helix was deleted to create a putative four-helix bundle protein. While the protein lacking helix-1 could be expressed in bacteria albeit at reduced yields, apoLp-III lacking helix-5 could not be produced. Mutational analysis by truncating helix-5 showed that a minimum segment of approximately one-third of the C-terminal helix is required for protein expression. The variant lacking helix-5 was produced by inserting a methionine residue between helix-4 and -5; subsequent cyanogenbromide cleavage generated the four-helix variant. Both N- and C-terminal helix deletion variants displayed significantly reduced helical content, protein stability, and tertiary structure. Despite the significantly altered structure, the variants were still fully functional. The rate of dimyristoylphosphatidylcholine vesicle solubilization was enhanced 4-5-fold compared to the wild-type protein, and the deletion variants were effective in binding to lipolyzed low density lipoprotein thereby preventing lipoprotein aggregation. These results show that the additional helix of apoLp-III is not essential for lipid binding but is required for proper folding to keep the protein into a stable conformation.
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Affiliation(s)
- Pankaj Dwivedi
- Department of Chemistry and Biochemistry, California State University , Long Beach, California 90840, United States
| | - Johana Rodriguez
- Department of Chemistry and Biochemistry, California State University , Long Beach, California 90840, United States
| | - Nnejiuwa U Ibe
- Department of Chemistry and Biochemistry, California State University , Long Beach, California 90840, United States
| | - Paul M M Weers
- Department of Chemistry and Biochemistry, California State University , Long Beach, California 90840, United States
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15
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Palusińska-Szysz M, Zdybicka-Barabas A, Reszczyńska E, Luchowski R, Kania M, Gisch N, Waldow F, Mak P, Danikiewicz W, Gruszecki WI, Cytryńska M. The lipid composition of Legionella dumoffii membrane modulates the interaction with Galleria mellonella apolipophorin III. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:617-29. [PMID: 27094351 DOI: 10.1016/j.bbalip.2016.04.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 04/11/2016] [Accepted: 04/15/2016] [Indexed: 11/26/2022]
Abstract
Apolipophorin III (apoLp-III), an insect homologue of human apolipoprotein E (apoE), is a widely used model protein in studies on protein-lipid interactions, and anti-Legionella activity of Galleria mellonella apoLp-III has been documented. Interestingly, exogenous choline-cultured Legionella dumoffii cells are considerably more susceptible to apoLp-III than non-supplemented bacteria. In order to explain these differences, we performed, for the first time, a detailed analysis of L. dumoffii lipids and a comparative lipidomic analysis of membranes of bacteria grown without and in the presence of exogenous choline. (31)P NMR analysis of L. dumoffii phospholipids (PLs) revealed a considerable increase in the phosphatidylcholine (PC) content in bacteria cultured on choline medium and a decrease in the phosphatidylethanolamine (PE) content in approximately the same range. The interactions of G. mellonella apoLp-III with lipid bilayer membranes prepared from PLs extracted from non- and choline-supplemented L. dumoffii cells were examined in detail by means of attenuated total reflection- and linear dichroism-Fourier transform infrared spectroscopy. Furthermore, the kinetics of apoLp-III binding to liposomes formed from L. dumoffii PLs was analysed by fluorescence correlation spectroscopy and fluorescence lifetime imaging microscopy using fluorescently labelled G. mellonella apoLp-III. Our results indicated enhanced binding of apoLp-III to and deeper penetration into lipid membranes formed from PLs extracted from the choline-supplemented bacteria, i.e. characterized by an increased PC/PE ratio. This could explain, at least in part, the higher susceptibility of choline-cultured L. dumoffii to G. mellonella apoLp-III.
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Affiliation(s)
- Marta Palusińska-Szysz
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
| | - Agnieszka Zdybicka-Barabas
- Department of Immunobiology, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
| | - Emilia Reszczyńska
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Square 1, 20-031 Lublin, Poland; Department of Biophysics, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
| | - Rafał Luchowski
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Square 1, 20-031 Lublin, Poland.
| | - Magdalena Kania
- Mass Spectrometry Group, Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52 St., 01-224 Warsaw, Poland.
| | - Nicolas Gisch
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, 23845 Borstel, Germany.
| | - Franziska Waldow
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, 23845 Borstel, Germany.
| | - Paweł Mak
- Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7 St., 30-387 Krakow; Malopolska Centre of Biotechnology, Gronostajowa 7A St., 30-387 Krakow, Poland.
| | - Witold Danikiewicz
- Mass Spectrometry Group, Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52 St., 01-224 Warsaw, Poland.
| | - Wiesław I Gruszecki
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Square 1, 20-031 Lublin, Poland.
| | - Małgorzata Cytryńska
- Department of Immunobiology, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
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16
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Dörr JM, Scheidelaar S, Koorengevel MC, Dominguez JJ, Schäfer M, van Walree CA, Killian JA. The styrene-maleic acid copolymer: a versatile tool in membrane research. Eur Biophys J 2016; 45:3-21. [PMID: 26639665 PMCID: PMC4698303 DOI: 10.1007/s00249-015-1093-y] [Citation(s) in RCA: 268] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/12/2015] [Accepted: 10/14/2015] [Indexed: 10/28/2022]
Abstract
A new and promising tool in membrane research is the detergent-free solubilization of membrane proteins by styrene-maleic acid copolymers (SMAs). These amphipathic molecules are able to solubilize lipid bilayers in the form of nanodiscs that are bounded by the polymer. Thus, membrane proteins can be directly extracted from cells in a water-soluble form while conserving a patch of native membrane around them. In this review article, we briefly discuss current methods of membrane protein solubilization and stabilization. We then zoom in on SMAs, describe their physico-chemical properties, and discuss their membrane-solubilizing effect. This is followed by an overview of studies in which SMA has been used to isolate and investigate membrane proteins. Finally, potential future applications of the methodology are discussed for structural and functional studies on membrane proteins in a near-native environment and for characterizing protein-lipid and protein-protein interactions.
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Affiliation(s)
- Jonas M Dörr
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
| | - Stefan Scheidelaar
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Martijn C Koorengevel
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Juan J Dominguez
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Marre Schäfer
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Cornelis A van Walree
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
- School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, 5001, Australia
| | - J Antoinette Killian
- Membrane Biochemistry and Biophysics, Bijvoet Center for Biomolecular Research and Institute of Biomembranes, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
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17
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Stepien P, Polit A, Wisniewska-Becker A. Comparative EPR studies on lipid bilayer properties in nanodiscs and liposomes. Biochim Biophys Acta 2015; 1848:60-6. [PMID: 25306967 DOI: 10.1016/j.bbamem.2014.10.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 09/19/2014] [Accepted: 10/01/2014] [Indexed: 12/17/2022]
Abstract
Studies of the membrane proteins suggest their close interaction with the lipid surroundings. Membrane proteins and their activities are affected by the composition and structure of the lipid bilayer. therefore adequate surroundings for studied protein are crucial for the model membrane to ensure its biological relevance. In recent years nanodiscs which are small fragments of lipid bilayer stabilised by derivatives of apolipoprotein, called membrane scaffold protein ( MSP), have been established as alternative tool in structural and functional studies of membrane proteins. In this study, the influence MSP of different length on structure and dynamics of DMPC and POPC bilayer was investigated and compared to bilayer present in liposomes. EPR spectroscopy technique using different PC-based spin probes was employed to show cholesterol-like organising effect of MSPs on lipid bilayer, thus giving a better insight into the nanodiscs model membrane structure, and its possible implications in the research of membrane protein applications.
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18
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Scheidelaar S, Koorengevel MC, Pardo JD, Meeldijk JD, Breukink E, Killian JA. Molecular model for the solubilization of membranes into nanodisks by styrene maleic Acid copolymers. Biophys J 2015; 108:279-90. [PMID: 25606677 PMCID: PMC4302193 DOI: 10.1016/j.bpj.2014.11.3464] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/20/2014] [Accepted: 11/24/2014] [Indexed: 01/11/2023] Open
Abstract
A recent discovery in membrane research is the ability of styrene-maleic acid (SMA) copolymers to solubilize membranes in the form of nanodisks allowing extraction and purification of membrane proteins from their native environment in a single detergent-free step. This has important implications for membrane research because it allows isolation as well as characterization of proteins and lipids in a near-native environment. Here, we aimed to unravel the molecular mode of action of SMA copolymers by performing systematic studies using model membranes of varying compositions and employing complementary biophysical approaches. We found that the SMA copolymer is a highly efficient membrane-solubilizing agent and that lipid bilayer properties such as fluidity, thickness, lateral pressure profile, and charge density all play distinct roles in the kinetics of solubilization. More specifically, relatively thin membranes, decreased lateral chain pressure, low charge density at the membrane surface, and increased salt concentration promote the speed and yield of vesicle solubilization. Experiments using a native membrane lipid extract showed that the SMA copolymer does not discriminate between different lipids and thus retains the native lipid composition in the solubilized particles. A model is proposed for the mode of action of SMA copolymers in which membrane solubilization is mainly driven by the hydrophobic effect and is further favored by physical properties of the polymer such as its relatively small cross-sectional area and rigid pendant groups. These results may be helpful for development of novel applications for this new type of solubilizing agent, and for optimization of the SMA technology for solubilization of the wide variety of cell membranes found in nature.
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Affiliation(s)
- Stefan Scheidelaar
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan, Utrecht, The Netherlands.
| | - Martijn C Koorengevel
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan, Utrecht, The Netherlands
| | - Juan Dominguez Pardo
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan, Utrecht, The Netherlands
| | - Johannes D Meeldijk
- Electron Microscopy Utrecht, Debye Institute of Nanomaterials Science, Faculty of Science, Utrecht University, Padualaan, Utrecht, The Netherlands
| | - Eefjan Breukink
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan, Utrecht, The Netherlands
| | - J Antoinette Killian
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan, Utrecht, The Netherlands
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19
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Zdybicka-barabas A, Palusińska-szysz M, Gruszecki WI, Mak P, Cytryńska M. Galleria mellonella apolipophorin III – an apolipoprotein with anti-Legionella pneumophila activity. Biochimica et Biophysica Acta (BBA) - Biomembranes 2014; 1838:2689-97. [DOI: 10.1016/j.bbamem.2014.07.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 06/23/2014] [Accepted: 07/01/2014] [Indexed: 12/19/2022]
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20
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Takase H, Furuchi H, Tanaka M, Yamada T, Matoba K, Iwasaki K, Kawakami T, Mukai T. Characterization of reconstituted high-density lipoprotein particles formed by lipid interactions with human serum amyloid A. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1842:1467-74. [PMID: 25063355 DOI: 10.1016/j.bbalip.2014.07.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Revised: 07/12/2014] [Accepted: 07/15/2014] [Indexed: 12/21/2022]
Abstract
The acute-phase human protein serum amyloid A (SAA) is enriched in high-density lipoprotein (HDL) in patients with inflammatory diseases. Compared with normal HDL containing apolipoprotein A-I, which is the principal protein component, characteristics of acute-phase HDL containing SAA remain largely undefined. In the present study, we examined the physicochemical properties of reconstituted HDL (rHDL) particles formed by lipid interactions with SAA. Fluorescence and circular dichroism measurements revealed that although SAA was unstructured at physiological temperature, α-helix formation was induced upon binding to phospholipid vesicles. SAA also formed rHDL particles by solubilizing phospholipid vesicles through mechanisms that are common to other exchangeable apolipoproteins. Dynamic light scattering and nondenaturing gradient gel electrophoresis analyses of rHDL after gel filtration revealed particle sizes of approximately 10nm, and a discoidal shape was verified by transmission electron microscopy. Thermal denaturation experiments indicated that SAA molecules in rHDL retained α-helical conformations at 37°C, but were almost completely denatured around 60°C. Furthermore, trypsin digestion experiments showed that lipid binding rendered SAA molecules resistant to protein degradation. In humans, three major SAA1 isoforms (SAA1.1, 1.3, and 1.5) are known. Although these isoforms have different amino acids at residues 52 and 57, no major differences in physicochemical properties between rHDL particles resulting from lipid interactions with SAA isoforms have been found. The present data provide useful insights into the effects of SAA enrichment on the physicochemical properties of HDL.
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Affiliation(s)
- Hiroka Takase
- Department of Biophysical Chemistry, Kobe Pharmaceutical University, Kobe 658-8558, Japan
| | - Hiroki Furuchi
- Department of Biophysical Chemistry, Kobe Pharmaceutical University, Kobe 658-8558, Japan
| | - Masafumi Tanaka
- Department of Biophysical Chemistry, Kobe Pharmaceutical University, Kobe 658-8558, Japan.
| | - Toshiyuki Yamada
- Department of Clinical and Laboratory Medicine, Jichi Medical University, Tochigi 329-0498, Japan
| | - Kyoko Matoba
- Laboratory of Protein Synthesis and Expression, Institute for Protein Research, Osaka University, Suita 565-0871, Japan
| | - Kenji Iwasaki
- Laboratory of Protein Synthesis and Expression, Institute for Protein Research, Osaka University, Suita 565-0871, Japan
| | - Toru Kawakami
- Laboratory of Protein Organic Chemistry, Institute for Protein Research, Osaka University, Suita 565-0871, Japan
| | - Takahiro Mukai
- Department of Biophysical Chemistry, Kobe Pharmaceutical University, Kobe 658-8558, Japan
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21
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Rathnayake SS, Mirheydari M, Schulte A, Gillahan JE, Gentit T, Phillips AN, Okonkwo RK, Burger KN, Mann EK, Vaknin D, Bu W, Agra-Kooijman DM, Kooijman EE. Insertion of apoLp-III into a lipid monolayer is more favorable for saturated, more ordered, acyl-chains. Biochim Biophys Acta 2014; 1838:482-92. [PMID: 24099741 DOI: 10.1016/j.bbamem.2013.09.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Revised: 09/20/2013] [Accepted: 09/25/2013] [Indexed: 11/22/2022]
Abstract
Neutral lipid transport in mammals is complicated involving many types of apolipoprotein. The exchangeable apolipoproteins mediate the transfer of hydrophobic lipids between tissues and particles, and bind to cell surface receptors. Amphipathic α-helices form a common structural motif that facilitates their lipid binding and exchangeability. ApoLp-III, the only exchangeable apolipoprotein found in insects, is a model amphipathic α-helix bundle protein and its three dimensional structure and function mimics that of the mammalian proteins apoE and apoAI. Even the intracellular exchangeable lipid droplet protein TIP47/perilipin 3 contains an α-helix bundle domain with high structural similarity to that of apoE and apoLp-III. Here, we investigated the interaction of apoLp-III from Locusta migratoria with lipid monolayers. Consistent with earlier work we find that insertion of apoLp-III into fluid lipid monolayers is highest for diacylglycerol. We observe a preference for saturated and more highly ordered lipids, suggesting a new mode of interaction for amphipathic α-helix bundles. X-ray reflectivity shows that apoLp-III unfolds at a hydrophobic interface and flexible loops connecting the amphipathic α-helices stay in solution. X-ray diffraction indicates that apoLp-III insertion into diacylglycerol monolayers induces additional ordering of saturated acyl-chains. These results thus shed important new insight into the protein-lipid interactions of a model exchangeable apolipoprotein with significant implications for its mammalian counterparts.
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Abstract
The nanodisc is a discoidal particle (~ 10-12 nm large) that trap membrane proteins into a small patch of phospholipid bilayer. The nanodisc is a particularly attractive option for studying membrane proteins, especially in the context of ligand-receptor interactions. The method pioneered by Sligar and colleagues is based on the amphipathic properties of an engineered highly a-helical scaffold protein derived from the apolipoprotein A1. The hydrophobic faces of the scaffold protein interact with the fatty acyl side-chains of the lipid bilayer whereas the polar regions face the aqueous environment. Analyses of membrane proteins in nanodiscs have significant advantages over liposome because the particles are small, homogeneous and water-soluble. In addition, biochemical and biophysical methods normally reserved to soluble proteins can be applied, and from either side of the membrane. In this visual protocol, we present a step-by-step reconstitution of a well characterized bacterial ABC transporter, the MalE-MalFGK2 complex. The formation of the disc is a self-assembly process that depends on hydrophobic interactions taking place during the progressive removal of the detergent. We describe the essential steps and we highlight the importance of choosing a correct protein-to-lipid ratio in order to limit the formation of aggregates and larger polydisperse liposome-like particles. Simple quality controls such as gel filtration chromatography, native gel electrophoresis and dynamic light scattering spectroscopy ensure that the discs have been properly reconstituted.
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Affiliation(s)
- Huan Bao
- Department of Biochemistry and Molecular Biology, University of British Columbia
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23
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Chièze L, Bolanos-Garcia VM, Le Caër G, Renault A, Vié V, Beaufils S. Difference in lipid packing sensitivity of exchangeable apolipoproteins apoA-I and apoA-II: an important determinant for their distinctive role in lipid metabolism. Biochim Biophys Acta 2012; 1818:2732-41. [PMID: 22627110 DOI: 10.1016/j.bbamem.2012.05.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 05/11/2012] [Accepted: 05/14/2012] [Indexed: 12/21/2022]
Abstract
Exchangeable apolipoproteins A-I and A-II play distinct roles in reverse cholesterol transport. ApoA-I interacts with phospholipids and cholesterol of the cell membrane to make high density lipoprotein particles whereas apolipoprotein A-II interacts with high density lipoprotein particles to release apolipoprotein A-I. The two proteins show a high activity at the aqueous solution/lipid interface and are characterized by a high content of amphipathic α-helices built upon repetition of the same structural motif. We set out to investigate to what extent the number of α-helix repeats of this structural motif modulates the affinity of the protein for lipids and the sensitivity to lipid packing. To this aim we have compared the insertion of apolipoproteins A-I and A-II in phospholipid monolayers formed on a Langmuir trough in conditions where lipid packing, surface pressure and charge were controlled. We also used atomic force microscopy to obtain high resolution topographic images of the surface at a resolution of several nanometers and performed statistical image analysis to calculate the spatial distribution and geometrical shape of apolipoproteins A-I and A-II clusters. Our data indicate that apolipoprotein A-I is sensitive to packing of zwitterionic lipids but insensitive to the packing of negatively charged lipids. Interestingly, apolipoprotein A-II proved to be insensitive to the packing of zwitterionic lipids. The different sensitivity to lipid packing provides clues as to why apolipoprotein A-II barely forms nascent high density lipoprotein particles while apolipoprotein A-I promotes their formation. We conclude that the different interfacial behaviors of apolipoprotein A-I and apolipoprotein A-II in lipidic monolayers are important determinants of their distinctive roles in lipid metabolism.
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Affiliation(s)
- Lionel Chièze
- Institut de Physique de Rennes, UMR-CNRS 6251 Université de Rennes 1, Campus de Beaulieu, Rennes cedex, France
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