51
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Ma L, Ge J, Bian X, Zhang Y. Single-Molecule Optical Tweezers Study of Protein-Membrane Interactions. Methods Mol Biol 2022; 2473:367-383. [PMID: 35819776 DOI: 10.1007/978-1-0716-2209-4_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Numerous proteins directly or indirectly bind membranes to exert their roles in a wide variety of biological processes. Such membrane binding often occurs in the presence of an external mechanical force. It remains challenging to quantify these interactions using traditional experimental approaches based on a large number of molecules, due to ensemble averaging or the lack of mechanical force. Here we described a new single-molecule approach based on high-resolution optical tweezers to characterize protein-membrane interactions. A single membrane binding protein is attached to the lipid bilayer coated on a silica bead via a flexible polypeptide linker, tethered to another bead via a long DNA handle, and pulled away from the bilayer using optical tweezers. Dynamic protein binding and unbinding is detected by the corresponding changes in the extension of the protein-DNA tether with high spatiotemporal resolution, which reveals the membrane binding affinity, kinetics, and intermediates. We demonstrated the method using C2 domains of extended synaptotagmin 2 (E-Syt2) with a detailed protocol. The method can be widely applied to investigate complex protein-membrane interactions under well-controlled experimental conditions.
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Affiliation(s)
- Lu Ma
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Jinghua Ge
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Xin Bian
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.
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52
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Surovtsev NV, Adichtchev SV. Dynamic response on a nanometer scale of binary phospholipid-cholesterol vesicles: Low-frequency Raman scattering insight. Phys Rev E 2021; 104:054406. [PMID: 34942765 DOI: 10.1103/physreve.104.054406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 10/18/2021] [Indexed: 11/07/2022]
Abstract
Low-frequency Raman spectroscopy was used to study the dynamic response on a nanometer scale of aqueous suspensions of two-component lipid vesicles. Binary mixtures of saturated phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC) and cholesterol are interesting for possible coexistence of solidlike and liquid-ordered phases, while the phase coexistence was not reported for unsaturated phospholipid (1,2-dioleoyl-sn-glycero-3-phosphocholine, DOPC) and cholesterol mixtures. The DOPC-DPPC mixtures represent the well-documented case of coexisting domains of solidlike and liquid-disordered phases. These three series of lipid mixtures are studied here. A broad peak with the maximum in the range of 30-50cm^{-1} and a narrow peak near 10cm^{-1} are observed in the Raman susceptibility of the binary mixtures and attributed to the acousticlike vibrational density of states and layer modes, respectively. Parameters of the broad and narrow peaks are sensitive to lateral and conformational hydrocarbon chain ordering. It was also demonstrated that the low-frequency Raman susceptibility of multicomponent lipid bilayers allows one to determine the phase state of lipid bilayers and distinguish the homogeneous distribution of molecular complexes from coexisting domains with sizes above several nanometers. Thus, the low-frequency Raman spectroscopy provides unique information in studying phase coexistence in lipid bilayers.
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Affiliation(s)
- N V Surovtsev
- Institute of Automation and Electrometry, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - S V Adichtchev
- Institute of Automation and Electrometry, Russian Academy of Sciences, Novosibirsk 630090, Russia
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53
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Reif B. Deuteration for High-Resolution Detection of Protons in Protein Magic Angle Spinning (MAS) Solid-State NMR. Chem Rev 2021; 122:10019-10035. [PMID: 34870415 DOI: 10.1021/acs.chemrev.1c00681] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Proton detection developed in the last 20 years as the method of choice to study biomolecules in the solid state. In perdeuterated proteins, proton dipolar interactions are strongly attenuated, which allows yielding of high-resolution proton spectra. Perdeuteration and backsubstitution of exchangeable protons is essential if samples are rotated with MAS rotation frequencies below 60 kHz. Protonated samples can be investigated directly without spin dilution using proton detection methods in case the MAS frequency exceeds 110 kHz. This review summarizes labeling strategies and the spectroscopic methods to perform experiments that yield assignments, quantitative information on structure, and dynamics using perdeuterated samples. Techniques for solvent suppression, H/D exchange, and deuterium spectroscopy are discussed. Finally, experimental and theoretical results that allow estimation of the sensitivity of proton detected experiments as a function of the MAS frequency and the external B0 field in a perdeuterated environment are compiled.
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Affiliation(s)
- Bernd Reif
- Bayerisches NMR Zentrum (BNMRZ) at the Department of Chemistry, Technische Universität München (TUM), Lichtenbergstr. 4, 85747 Garching, Germany.,Helmholtz-Zentrum München (HMGU), Deutsches Forschungszentrum für Gesundheit und Umwelt, Institute of Structural Biology (STB), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
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54
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Yuan S, Zhang H, Wang X, Zhang H, Zhang Z, Yuan S. Molecular insights into the uptake of SiO 2 nanoparticles on phospholipid membrane: Effect of surface properties and particle size. Colloids Surf B Biointerfaces 2021; 210:112250. [PMID: 34861541 DOI: 10.1016/j.colsurfb.2021.112250] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/23/2021] [Accepted: 11/24/2021] [Indexed: 11/24/2022]
Abstract
Silica (SiO2) nanoparticles (NPs) have attracted much attention due to the potential for a wide range of applications and they have been confirmed to be hazardous to humans. Partitioning to phospholipid bilayers is an important way for their bioaccumulation. However, the detailed mechanism of SiO2 NPs uptake by membrane phospholipids remains uncertain. In this work, molecular dynamics (MD) simulations were employed to study the uptake process of SiO2 NPs into DPPC bilayers. Results show that these SiO2 NPs uptake onto DPPC bilayer surface is favorable from the viewpoint of thermodynamics. During the uptake process, the SiO2 NP needed to adjust the angle of interaction with the DPPC surface until the most stable adsorption configuration was reached. After incorporating into DPPC bilayers, the interaction between PO4- group and SiO2 particle is stronger than -N+(CH3)3 group and SiO2. Small SiO2 NP was found to adsorb to the surface of DPPC bilayer without disturbing the morphology or membrane. In contract, bioaccumulation of large SiO2 NP to DPPC induced a strong local membrane deformation. In addition, the effect of SiO2 NP surface functionalization on its interaction with DPPC was also investigated. This molecular-level study reports a complete description of the interaction between SiO2 NPs and DPPC bilayer, aiming to provide some insights for the further work on the bioaccumulation and hemolytic activity of SiO2 NPs.
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Affiliation(s)
- Shideng Yuan
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China
| | - Heng Zhang
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China
| | - Xueyu Wang
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China
| | - Hengming Zhang
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China
| | - Zhenyu Zhang
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China
| | - Shiling Yuan
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China.
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55
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Keable SM, Kölsch A, Simon PS, Dasgupta M, Chatterjee R, Subramanian SK, Hussein R, Ibrahim M, Kim IS, Bogacz I, Makita H, Pham CC, Fuller FD, Gul S, Paley D, Lassalle L, Sutherlin KD, Bhowmick A, Moriarty NW, Young ID, Blaschke JP, de Lichtenberg C, Chernev P, Cheah MH, Park S, Park G, Kim J, Lee SJ, Park J, Tono K, Owada S, Hunter MS, Batyuk A, Oggenfuss R, Sander M, Zerdane S, Ozerov D, Nass K, Lemke H, Mankowsky R, Brewster AS, Messinger J, Sauter NK, Yachandra VK, Yano J, Zouni A, Kern J. Room temperature XFEL crystallography reveals asymmetry in the vicinity of the two phylloquinones in photosystem I. Sci Rep 2021; 11:21787. [PMID: 34750381 PMCID: PMC8575901 DOI: 10.1038/s41598-021-00236-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 09/02/2021] [Indexed: 11/09/2022] Open
Abstract
Photosystem I (PS I) has a symmetric structure with two highly similar branches of pigments at the center that are involved in electron transfer, but shows very different efficiency along the two branches. We have determined the structure of cyanobacterial PS I at room temperature (RT) using femtosecond X-ray pulses from an X-ray free electron laser (XFEL) that shows a clear expansion of the entire protein complex in the direction of the membrane plane, when compared to previous cryogenic structures. This trend was observed by complementary datasets taken at multiple XFEL beamlines. In the RT structure of PS I, we also observe conformational differences between the two branches in the reaction center around the secondary electron acceptors A1A and A1B. The π-stacked Phe residues are rotated with a more parallel orientation in the A-branch and an almost perpendicular confirmation in the B-branch, and the symmetry breaking PsaB-Trp673 is tilted and further away from A1A. These changes increase the asymmetry between the branches and may provide insights into the preferential directionality of electron transfer.
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Affiliation(s)
- Stephen M Keable
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Adrian Kölsch
- Institut für Biologie, Humboldt-Universität Zu Berlin, 10115, Berlin, Germany
| | - Philipp S Simon
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Medhanjali Dasgupta
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Ruchira Chatterjee
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | | | - Rana Hussein
- Institut für Biologie, Humboldt-Universität Zu Berlin, 10115, Berlin, Germany
| | - Mohamed Ibrahim
- Institut für Biologie, Humboldt-Universität Zu Berlin, 10115, Berlin, Germany
| | - In-Sik Kim
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Isabel Bogacz
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Hiroki Makita
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Cindy C Pham
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Franklin D Fuller
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Sheraz Gul
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Daniel Paley
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Louise Lassalle
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kyle D Sutherlin
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Asmit Bhowmick
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Nigel W Moriarty
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Iris D Young
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, 94158, USA
| | - Johannes P Blaschke
- National Energy Research Scientific Computing Center, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Casper de Lichtenberg
- Department of Chemistry - Ångström, Molecular Biomimetics, Uppsala University, 75237, Uppsala, Sweden.,Department of Chemistry, Umeå University, Linnaeus väg 6 (KBC huset), 90187, Umeå, Sweden
| | - Petko Chernev
- Department of Chemistry - Ångström, Molecular Biomimetics, Uppsala University, 75237, Uppsala, Sweden
| | - Mun Hon Cheah
- Department of Chemistry - Ångström, Molecular Biomimetics, Uppsala University, 75237, Uppsala, Sweden
| | - Sehan Park
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Korea
| | - Gisu Park
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Korea
| | - Jangwoo Kim
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Korea
| | - Sang Jae Lee
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Korea
| | - Jaehyun Park
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Korea
| | - Kensuke Tono
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan.,RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5148, Japan
| | - Shigeki Owada
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan.,RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5148, Japan
| | - Mark S Hunter
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Alexander Batyuk
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | | | | | | | | | - Karol Nass
- Paul Scherrer Institut, 5232, Villigen, Switzerland
| | - Henrik Lemke
- Paul Scherrer Institut, 5232, Villigen, Switzerland
| | | | - Aaron S Brewster
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Johannes Messinger
- Department of Chemistry - Ångström, Molecular Biomimetics, Uppsala University, 75237, Uppsala, Sweden
| | - Nicholas K Sauter
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Vittal K Yachandra
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Junko Yano
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Athina Zouni
- Institut für Biologie, Humboldt-Universität Zu Berlin, 10115, Berlin, Germany
| | - Jan Kern
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
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56
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Hu Z, Martí J, Lu H. Structure of benzothiadiazine at zwitterionic phospholipid cell membranes. J Chem Phys 2021; 155:154303. [PMID: 34686044 DOI: 10.1063/5.0065163] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The use of drugs derived from benzothiadiazine, which is a bicyclic heterocyclic benzene derivative, has become a widespread treatment for diseases such as hypertension (treated with diuretics such as bendroflumethiazide or chlorothiazide), low blood sugar (treated with non-diuretic diazoxide), or the human immunodeficiency virus, among others. In this work, we have investigated the interactions of benzothiadiazine with the basic components of cell membranes and solvents, such as phospholipids, cholesterol, ions, and water. The analysis of the mutual microscopic interactions is of central importance to elucidate the local structure of benzothiadiazine as well as the mechanisms responsible for the access of benzothiadiazine to the interior of the cell. We have performed molecular dynamics simulations of benzothiadiazine embedded in three different model zwitterionic bilayer membranes made by dimyristoylphosphatidylcholine, dioleoylphosphatidylcholine, 1,2-dioleoyl-sn-glycero-3-phosphoserine, and cholesterol inside aqueous sodium-chloride solution in order to systematically examine microscopic interactions of benzothiadiazine with the cell membrane at liquid-crystalline phase conditions. From data obtained through radial distribution functions, hydrogen-bonding lengths, and potentials of mean force based on reversible work calculations, we have observed that benzothiadiazine has a strong affinity to stay at the cell membrane interface although it can be fully solvated by water in short periods of time. Furthermore, benzothiadiazine is able to bind lipids and cholesterol chains by means of single and double hydrogen-bonds of different characteristic lengths.
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Affiliation(s)
- Zheyao Hu
- Department of Physics, Technical University of Catalonia-Barcelona Tech, B5-209 Northern Campus UPC, 08034 Barcelona, Catalonia, Spain
| | - Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, B5-209 Northern Campus UPC, 08034 Barcelona, Catalonia, Spain
| | - Huixia Lu
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
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57
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Gracheva IA, Tretiakova DS, Zamyshlyaeva OG, Kudriashova ES, Vodovozova EL, Fedorov AY, Boldyrev IA. Cy5-Labeled Phosphatidylcholine. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2021. [DOI: 10.1134/s1068162021050265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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58
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Permeation pathway of two hydrophobic carbon nanoparticles across a lipid bilayer. J CHEM SCI 2021. [DOI: 10.1007/s12039-021-01968-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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59
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Kumar N, Sastry GN. Study of lipid heterogeneity on bilayer membranes using molecular dynamics simulations. J Mol Graph Model 2021; 108:108000. [PMID: 34365255 DOI: 10.1016/j.jmgm.2021.108000] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/17/2021] [Accepted: 07/29/2021] [Indexed: 11/26/2022]
Abstract
Human cell membranes consist of various lipids that are essential for their structure and function. It typically comprises phosphatidylcholine (POPC), phosphatidylethanolamine (POPE), phosphatidylserine (POPS), sphingomyelin (PSM), and cholesterol (CHL). Several experimental and computational techniques have been employed to characterize the composition of human cell membranes, however, CHL enriched membrane is still not clearly understood through these techniques. Molecular dynamics simulation results illustrated the biophysical properties of heterogeneous membranes based on the lipid composition as well as the concentration of lipids, exclusively for CHL and PSM. Herein, we have investigated the structure-function relationships of lipids comparatively to delineate the effect of heterogeneity on the biophysical properties of different membranes. It has been observed that the significant fraction of CHL (i.e., ~33% in ternary, ~25% in quaternary, and ~16% in senary type bilayers) in combination with other lipids introduced compactness, and increased the thickness of the membrane. The analysis of lipid mass density stated that the density of lipid head group, phosphate, and glycerol-ester in presence of CHL with or without PSM is an underlying reason for membrane ordering. Results also revealed that the presence of POPI and POPS are the reasons for an adequate drop in the ordering of lipid chain, particularly on POPE chain. The self-interaction of CHL, PSM, POPE and the interaction of CHL and POPC with POPE seem to determine the structure and function of the heterogeneous membrane. Our findings provide a qualitative understanding of the effect of membrane heterogeneity on the physiological properties of membranes. The structures inspected in this study would help to select the heterogeneous bilayer model to mimic the human cell membranes to analyse or characterize the membrane-associated phenomena.
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Affiliation(s)
- Nandan Kumar
- Centre for Molecular Modelling, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500007, Telangana State, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, U. P., India
| | - G Narahari Sastry
- Centre for Molecular Modelling, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500007, Telangana State, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, U. P., India; Advanced Computation and Data Sciences Division, CSIR-North East Institute of Science and Technology, Jorhat, 785006, Assam, India.
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60
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Impact of Selected Small-Molecule Kinase Inhibitors on Lipid Membranes. Pharmaceuticals (Basel) 2021; 14:ph14080746. [PMID: 34451842 PMCID: PMC8401620 DOI: 10.3390/ph14080746] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 07/26/2021] [Accepted: 07/26/2021] [Indexed: 01/20/2023] Open
Abstract
Small-molecule protein kinase inhibitors are used for the treatment of various diseases. Although their effect(s) on the respective kinase are generally quite well understood, surprisingly, their interaction with membranes is only barely investigated; even though these drugs necessarily come into contact with the plasma and intracellular membranes. Using biophysical methods such as NMR, ESR, and fluorescence spectroscopy in combination with lipid vesicles, we studied the membrane interaction of the kinase inhibitors sunitinib, erlotinib, idelalisib, and lenvatinib; these drugs are characterized by medium log p values, a parameter reflecting the overall hydrophobicity of the molecules, which is one important parameter to predict the interaction with lipid membranes. While all four molecules tend to embed in a similar region of the lipid membrane, their presence has different impacts on membrane structure and dynamics. Most notably, sunitinib, exhibiting the lowest log p value of the four inhibitors, effectively influences membrane integrity, while the others do not. This shows that the estimation of the effect of drug molecules on lipid membranes can be rather complex. In this context, experimental studies on lipid membranes are necessary to (i) identify drugs that may disturb membranes and (ii) characterize drug-membrane interactions on a molecular level. Such knowledge is important for understanding the efficacy and potential side effects of respective drugs.
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61
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Abstract
Cell membranes - primarily composed of lipids, sterols, and proteins - form a dynamic interface between living cells and their environment. They act as a mechanical barrier around the cell while selectively facilitating material transport, signal transduction, and various other functions necessary for the cell viability. The complex functionality of cell membranes and the hierarchical motions and responses they exhibit demand a thorough understanding of the origin of different membrane dynamics and how they are influenced by molecular additives and environmental cues. These dynamic modes include single-molecule diffusion, thermal fluctuations, and large-scale membrane deformations, to name a few. This review highlights advances in investigating structure-driven dynamics associated with model cell membranes, with a particular focus on insights gained from neutron scattering and spectroscopy experiments. We discuss the uniqueness of neutron contrast variation and its remarkable potential in probing selective membrane structure and dynamics on spatial and temporal scales over which key biological functions occur. We also present a summary of current and future opportunities in synergistic combinations of neutron scattering with molecular dynamics (MD) simulations to gain further understanding of the molecular mechanisms underlying complex membrane functions.
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Affiliation(s)
- Sudipta Gupta
- Department of Physics, Virginia Tech, Blacksburg, VA 24061, USA. and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA 24061, USA
| | - Rana Ashkar
- Department of Physics, Virginia Tech, Blacksburg, VA 24061, USA. and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA 24061, USA
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62
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Endoplasmic reticulum phospholipid scramblase activity revealed after protein reconstitution into giant unilamellar vesicles containing a photostable lipid reporter. Sci Rep 2021; 11:14364. [PMID: 34257324 PMCID: PMC8277826 DOI: 10.1038/s41598-021-93664-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/28/2021] [Indexed: 02/04/2023] Open
Abstract
Transbilayer movement of phospholipids in biological membranes is mediated by a diverse set of lipid transporters. Among them are scramblases that facilitate a rapid bi-directional movement of lipids without metabolic energy input. Here, we established a new fluorescence microscopy-based assay for detecting phospholipid scramblase activity of membrane proteins upon their reconstitution into giant unilamellar vesicles formed from proteoliposomes by electroformation. The assay is based on chemical bleaching of fluorescence of a photostable ATTO-dye labeled phospholipid with the membrane-impermeant reductant sodium dithionite. We demonstrate that this new methodology is suitable for the study of the scramblase activity of the yeast endoplasmic reticulum at single vesicle level.
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63
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Silva TFD, Vila-Viçosa D, Machuqueiro M. Improved Protocol to Tackle the pH Effects on Membrane-Inserting Peptides. J Chem Theory Comput 2021; 17:3830-3840. [PMID: 34115492 DOI: 10.1021/acs.jctc.1c00020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Many important biological pathways rely on membrane-interacting peptides or proteins, which can alter the biophysical properties of the cell membrane by simply adsorbing to its surface to undergo a full insertion process. To study these phenomena with atomistic detail, model peptides have been used to refine the current computational methodologies. Improvements have been made with force-field parameters, enhanced sampling techniques to obtain faster sampling, and the addition of chemical-physical properties, such as pH, whose influence dramatically increases at the water/membrane interface. The pH (low) insertion peptide (pHLIP) is a peptide that inserts across a membrane bilayer depending on the pH due to the presence of a key residue (Asp14) whose acidity-induced protonation triggers the whole process. The complex nature of these peptide/membrane interactions resulted in sampling limitations of the protonation and configurational space albeit using state-of-the-art methods such as the constant-pH molecular dynamics. To address this issue and circumvent those limitations, new simulations were performed with our newly developed pH-replica exchange method using wild-type (wt)-pHLIP in different 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine membrane sizes. This technique provided enhanced sampling and allowed for the calculation of more complete Asp14 pKa profiles. The conformational heterogeneity derived from strong electrostatic interactions between Asp14 and the lipid phosphate groups was identified as the source of most pKa variability. In spite of these persistent and harder-to-equilibrate phosphate interactions, the pKa values at deeper regions (6.0-6.2) still predicted the experimental pK of insertion (6.0) since the electrostatic perturbation decays as the residue inserts further into the membrane. We also observed that reducing the system size leads to membrane deformations where it increasingly loses the ability to accommodate the pHLIP-induced perturbations. This indicates that large membrane patches, such as 256 or even 352 lipids, are needed to obtain stable and more realistic pHLIP/membrane systems. These results strengthen our method pKa predictive and analytical capabilities to study the intricate play of electrostatic effects of the peptide/membrane interface, granting confidence for future applications in similar systems.
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Affiliation(s)
- Tomás F D Silva
- Departamento de Química e Bioquímica, Faculdade de Ciências, BioISI: Biosystems and Integrative Sciences Institute, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Diogo Vila-Viçosa
- Departamento de Química e Bioquímica, Faculdade de Ciências, BioISI: Biosystems and Integrative Sciences Institute, Universidade de Lisboa, 1749-016 Lisboa, Portugal.,Kinetikos, Coimbra, Portugal
| | - Miguel Machuqueiro
- Departamento de Química e Bioquímica, Faculdade de Ciências, BioISI: Biosystems and Integrative Sciences Institute, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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Walter V, Ruscher C, Benzerara O, Thalmann F. MLLPA: A Machine Learning-assisted Python module to study phase-specific events in lipid membranes. J Comput Chem 2021; 42:930-943. [PMID: 33675541 DOI: 10.1002/jcc.26508] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/28/2021] [Accepted: 02/19/2021] [Indexed: 01/05/2023]
Abstract
Machine Learning-assisted Lipid Phase Analysis (MLLPA) is a new Python 3 module developed to analyze phase domains in a lipid membrane based on lipid molecular states. Reading standard simulation coordinate and trajectory files, the software first analyze the phase composition of the lipid membrane by using machine learning tools to label each individual molecules with respect to their state, and then decompose the simulation box using Voronoi tessellations to analyze the local environment of all the molecules of interest. MLLPA is versatile as it can read from multiple format (e.g., GROMACS, LAMMPS) and from either all-atom (e.g., CHARMM36) or coarse-grain models (e.g., Martini). It can also analyze multiple geometries of membranes (e.g., bilayers, vesicles). Finally, the software allows for training with more than two phases, allowing for multiple phase coexistence analysis.
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Affiliation(s)
- Vivien Walter
- Department of Chemistry, King's College London, London, UK
| | - Céline Ruscher
- Institut Charles Sadron - UPR 22, CNRS and University of Strasbourg, Strasbourg, France
| | - Olivier Benzerara
- Institut Charles Sadron - UPR 22, CNRS and University of Strasbourg, Strasbourg, France
| | - Fabrice Thalmann
- Institut Charles Sadron - UPR 22, CNRS and University of Strasbourg, Strasbourg, France
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Dey S, Surendran D, Engberg O, Gupta A, Fanibunda SE, Das A, Maity BK, Dey A, Visvakarma V, Kallianpur M, Scheidt HA, Walker G, Vaidya VA, Huster D, Maiti S. Altered Membrane Mechanics Provides a Receptor-Independent Pathway for Serotonin Action. Chemistry 2021; 27:7533-7541. [PMID: 33502812 PMCID: PMC8252079 DOI: 10.1002/chem.202100328] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Indexed: 12/20/2022]
Abstract
Serotonin, an important signaling molecule in humans, has an unexpectedly high lipid membrane affinity. The significance of this finding has evoked considerable speculation. Here we show that membrane binding by serotonin can directly modulate membrane properties and cellular function, providing an activity pathway completely independent of serotonin receptors. Atomic force microscopy shows that serotonin makes artificial lipid bilayers softer, and induces nucleation of liquid disordered domains inside the raft-like liquid-ordered domains. Solid-state NMR spectroscopy corroborates this data at the atomic level, revealing a homogeneous decrease in the order parameter of the lipid chains in the presence of serotonin. In the RN46A immortalized serotonergic neuronal cell line, extracellular serotonin enhances transferrin receptor endocytosis, even in the presence of broad-spectrum serotonin receptor and transporter inhibitors. Similarly, it increases the membrane binding and internalization of oligomeric peptides. Our results uncover a mode of serotonin-membrane interaction that can potentiate key cellular processes in a receptor-independent fashion.
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Affiliation(s)
- Simli Dey
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Dayana Surendran
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Oskar Engberg
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Ankur Gupta
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Sashaina E. Fanibunda
- Department of Biological SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
- Kasturba Health SocietyMedical Research CenterMumbaiIndia
| | - Anirban Das
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Barun Kumar Maity
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Arpan Dey
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Vicky Visvakarma
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Mamata Kallianpur
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Holger A. Scheidt
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Gilbert Walker
- Department of ChemistryUniversity of TorontoTorontoOntarioM5S3H6Canada
| | - Vidita A. Vaidya
- Department of Biological SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
| | - Daniel Huster
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Sudipta Maiti
- Department of Chemical SciencesTata Institute of Fundamental ResearchHomi Bhabha Road, ColabaMumbai400005India
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66
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Nagarajan SK, Babu S, Kulkarni SA, Vadivelu A, Devaraju P, Sohn H, Madhavan T. Understanding the influence of lipid bilayers and ligand molecules in determining the conformational dynamics of somatostatin receptor 2. Sci Rep 2021. [PMID: 33828200 DOI: 10.1038/s41598‐021‐87422‐5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Somatostatin receptor 2 (SSTR2) is a G-protein coupled receptor (GPCR) that controls numerous cellular processes including cell-to-cell signaling. In this study, we report how the lipid and ligand molecules influence the conformational dynamics of the membrane-bound SSTR2. Molecular simulations of different holo and apoenzyme complexes of SSTR2 in the presence and absence of a lipid bilayer were performed, observed, and correlated with previously reported studies. We identified the important SSTR2 residues that take part in the formation of the SSTR2-ligand complex. On analyzing the molecular simulation trajectories, we identified that the residue D3.32 is crucial in determining the bioactive conformation of SSTR2 ligands in the binding site. Based on the results, we suggest that designing a novel SSTR2 ligand with an H-bond donor group at the R1 position, and hydrophobic groups at R2 and R3 might have higher activity and SSTR2-selectivity. We analyzed the simulated systems to identify other important structural features involved in SSTR2-ligand binding and to observe the different conformational changes that occur in the protein after the ligand binding. Additionally, we studied the conformational dynamics of N- and C-terminal regions of SSTR2 in the presence and absence of the lipid bilayer. Both the systems were compared to understand the influence of lipid molecules in the formation of secondary structural domains by these extracellular regions. The comparative study revealed that the secondary structural elements formed by C-terminal residues in presence of lipid molecules is crucial for the functioning of SSTR2. Our study results highlight the structural complexities involved in the functioning of SSTR upon binding with the ligands in the presence and absence of lipid bilayer, which is essential for designing novel drug targets.
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Affiliation(s)
- Santhosh Kumar Nagarajan
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai, 603203, India
| | - Sathya Babu
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai, 603203, India
| | - Seema A Kulkarni
- Department of Food and Process Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai, 603203, India
| | - Aanand Vadivelu
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai, 603203, India
| | - Panneer Devaraju
- Unit of Vector Biology and Control, ICMR-Vector Control Research Centre, Indian Council of Medical Research (ICMR), Puducherry, India
| | - Honglae Sohn
- Department of Chemistry and Department of Carbon Materials, Chosun University, Gwangju, South Korea.
| | - Thirumurthy Madhavan
- Computational Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai, 603203, India.
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67
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Understanding the influence of lipid bilayers and ligand molecules in determining the conformational dynamics of somatostatin receptor 2. Sci Rep 2021; 11:7677. [PMID: 33828200 PMCID: PMC8027056 DOI: 10.1038/s41598-021-87422-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/26/2021] [Indexed: 11/11/2022] Open
Abstract
Somatostatin receptor 2 (SSTR2) is a G-protein coupled receptor (GPCR) that controls numerous cellular processes including cell-to-cell signaling. In this study, we report how the lipid and ligand molecules influence the conformational dynamics of the membrane-bound SSTR2. Molecular simulations of different holo and apoenzyme complexes of SSTR2 in the presence and absence of a lipid bilayer were performed, observed, and correlated with previously reported studies. We identified the important SSTR2 residues that take part in the formation of the SSTR2-ligand complex. On analyzing the molecular simulation trajectories, we identified that the residue D3.32 is crucial in determining the bioactive conformation of SSTR2 ligands in the binding site. Based on the results, we suggest that designing a novel SSTR2 ligand with an H-bond donor group at the R1 position, and hydrophobic groups at R2 and R3 might have higher activity and SSTR2-selectivity. We analyzed the simulated systems to identify other important structural features involved in SSTR2-ligand binding and to observe the different conformational changes that occur in the protein after the ligand binding. Additionally, we studied the conformational dynamics of N- and C-terminal regions of SSTR2 in the presence and absence of the lipid bilayer. Both the systems were compared to understand the influence of lipid molecules in the formation of secondary structural domains by these extracellular regions. The comparative study revealed that the secondary structural elements formed by C-terminal residues in presence of lipid molecules is crucial for the functioning of SSTR2. Our study results highlight the structural complexities involved in the functioning of SSTR upon binding with the ligands in the presence and absence of lipid bilayer, which is essential for designing novel drug targets.
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68
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Kleinwächter IS, Pannwitt S, Centi A, Hellmann N, Thines E, Bereau T, Schneider D. The Bacteriostatic Activity of 2-Phenylethanol Derivatives Correlates with Membrane Binding Affinity. MEMBRANES 2021; 11:membranes11040254. [PMID: 33807437 PMCID: PMC8067230 DOI: 10.3390/membranes11040254] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 11/16/2022]
Abstract
The hydrophobic tails of aliphatic primary alcohols do insert into the hydrophobic core of a lipid bilayer. Thereby, they disrupt hydrophobic interactions between the lipid molecules, resulting in a decreased lipid order, i.e., an increased membrane fluidity. While aromatic alcohols, such as 2-phenylethanol, also insert into lipid bilayers and disturb the membrane organization, the impact of aromatic alcohols on the structure of biological membranes, as well as the potential physiological implication of membrane incorporation has only been studied to a limited extent. Although diverse targets are discussed to be causing the bacteriostatic and bactericidal activity of 2-phenylethanol, it is clear that 2-phenylethanol severely affects the structure of biomembranes, which has been linked to its bacteriostatic activity. Yet, in fungi some 2-phenylethanol derivatives are also produced, some of which appear to also have bacteriostatic activities. We showed that the 2-phenylethanol derivatives phenylacetic acid, phenyllactic acid, and methyl phenylacetate, but not Tyrosol, were fully incorporated into model membranes and affected the membrane organization. Furthermore, we observed that the propensity of the herein-analyzed molecules to partition into biomembranes positively correlated with their respective bacteriostatic activity, which clearly linked the bacteriotoxic activity of the substances to biomembranes.
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Affiliation(s)
- Isabel S. Kleinwächter
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
| | - Stefanie Pannwitt
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
| | - Alessia Centi
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany; (A.C.); (T.B.)
| | - Nadja Hellmann
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
| | - Eckhard Thines
- Institute of Molecular Physiology, Johannes Gutenberg University, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany;
| | - Tristan Bereau
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany; (A.C.); (T.B.)
- Van ‘t Hoff Institute for Molecular Sciences and Informatics Institute, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Dirk Schneider
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany; (A.C.); (T.B.)
- Correspondence: ; Tel.: +49-6131-39-25833; Fax: +49-6131-39-25348
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69
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Martí J, Lu H. Microscopic Interactions of Melatonin, Serotonin and Tryptophan with Zwitterionic Phospholipid Membranes. Int J Mol Sci 2021; 22:2842. [PMID: 33799606 PMCID: PMC8001758 DOI: 10.3390/ijms22062842] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 12/15/2022] Open
Abstract
The interactions at the atomic level between small molecules and the main components of cellular plasma membranes are crucial for elucidating the mechanisms allowing for the entrance of such small species inside the cell. We have performed molecular dynamics and metadynamics simulations of tryptophan, serotonin, and melatonin at the interface of zwitterionic phospholipid bilayers. In this work, we will review recent computer simulation developments and report microscopic properties, such as the area per lipid and thickness of the membranes, atomic radial distribution functions, angular orientations, and free energy landscapes of small molecule binding to the membrane. Cholesterol affects the behaviour of the small molecules, which are mainly buried in the interfacial regions. We have observed a competition between the binding of small molecules to phospholipids and cholesterol through lipidic hydrogen-bonds. Free energy barriers that are associated to translational and orientational changes of melatonin have been found to be between 10-20 kJ/mol for distances of 1 nm between melatonin and the center of the membrane. Corresponding barriers for tryptophan and serotonin that are obtained from reversible work methods are of the order of 10 kJ/mol and reveal strong hydrogen bonding between such species and specific phospholipid sites. The diffusion of tryptophan and melatonin is of the order of 10-7 cm2/s for the cholesterol-free and cholesterol-rich setups.
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Affiliation(s)
- Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, 08034 Barcelona, Spain
| | - Huixia Lu
- School of Pharmacy, Shanghai Jiaotong University, Shanghai 200240, China;
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70
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Valentine ML, Waterland MK, Fathizadeh A, Elber R, Baiz CR. Interfacial Dynamics in Lipid Membranes: The Effects of Headgroup Structures. J Phys Chem B 2021; 125:1343-1350. [DOI: 10.1021/acs.jpcb.0c08755] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Mason L. Valentine
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712-1224, United States
| | - Maya K. Waterland
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712-1224, United States
| | - Arman Fathizadeh
- Oden Institute for Computational Science and Engineering, Austin, Texas 78712, United States
| | - Ron Elber
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712-1224, United States
- Oden Institute for Computational Science and Engineering, Austin, Texas 78712, United States
| | - Carlos R. Baiz
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712-1224, United States
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71
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Reif B, Ashbrook SE, Emsley L, Hong M. Solid-state NMR spectroscopy. NATURE REVIEWS. METHODS PRIMERS 2021; 1:2. [PMID: 34368784 PMCID: PMC8341432 DOI: 10.1038/s43586-020-00002-1] [Citation(s) in RCA: 187] [Impact Index Per Article: 62.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/29/2020] [Indexed: 12/18/2022]
Abstract
Solid-state nuclear magnetic resonance (NMR) spectroscopy is an atomic-level method used to determine the chemical structure, three-dimensional structure, and dynamics of solids and semi-solids. This Primer summarizes the basic principles of NMR as applied to the wide range of solid systems. The fundamental nuclear spin interactions and the effects of magnetic fields and radiofrequency pulses on nuclear spins are the same as in liquid-state NMR. However, because of the anisotropy of the interactions in the solid state, the majority of high-resolution solid-state NMR spectra is measured under magic-angle spinning (MAS), which has profound effects on the types of radiofrequency pulse sequences required to extract structural and dynamical information. We describe the most common MAS NMR experiments and data analysis approaches for investigating biological macromolecules, organic materials, and inorganic solids. Continuing development of sensitivity-enhancement approaches, including 1H-detected fast MAS experiments, dynamic nuclear polarization, and experiments tailored to ultrahigh magnetic fields, is described. We highlight recent applications of solid-state NMR to biological and materials chemistry. The Primer ends with a discussion of current limitations of NMR to study solids, and points to future avenues of development to further enhance the capabilities of this sophisticated spectroscopy for new applications.
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Affiliation(s)
- Bernd Reif
- Technische Universität München, Department Chemie, Lichtenbergstr. 4, D-85747 Garching, Germany
| | - Sharon E. Ashbrook
- School of Chemistry, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK
| | - Lyndon Emsley
- École Polytechnique Fédérale de Lausanne (EPFL), Institut des sciences et ingénierie chimiques, CH-1015 Lausanne, Switzerland
| | - Mei Hong
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, 170 Albany Street, Cambridge, MA 02139
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72
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Ohnari H, Naru E, Ogura T, Sakata O, Obata Y. Phase Separation in Lipid Lamellae Result from Ceramide Conformations and Lateral Packing Structure. Chem Pharm Bull (Tokyo) 2021; 69:72-80. [PMID: 33390523 DOI: 10.1248/cpb.c20-00588] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intercellular lipids in the stratum corneum protect the living body from invasion by allergens and pathogens, and also suppresses water evaporation within the body. It is important to understand how differences in the microstructure of intercellular lipids arise. This microstructure is affected by lipid composition. Studies using intercellular lipid models have reported the formation of two phases with different short lamellar periodicities. However, the details of the packing structure characteristics of the two phases observed in these intercellular lipid models are unclear. Our previous report revealed that different short periodicity phases coexist in the N-(α-hydroxyoctadecanoyl)-dihydrosphingosine (CER[ADS]), cholesterol (CHOL), and palmitic acid (PA) complex model. In this study, the characteristics of the packing structure of two phases with different short lamellar periodicities, which were observed in the intercellular lipid model (CER[ADS]/CHOL/PA) that we used previously, were adjusted for models with different lipid compositions. The characteristics of the packed and lamellar structures have been determined by temperature-scanning small-angle X-ray scattering and wide-angle X-ray diffraction measurements simultaneously. These differences in lamellar structure were thought to be caused by differences in ceramides (CER) conformation between the hairpin and the V-shape type. The lamellar structure of the V-shaped CER conformation has a low orthorhombic ratio. The above results suggest that an increase in the ratio of CER with the V-shaped structure causes the lamellar structure to have low orthorhombic ratio, thereby contributing to a decrease in the bilayer's barrier function.
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Affiliation(s)
| | - Eiji Naru
- Research and Development Division, KOSE Corporation
| | - Taku Ogura
- Research Institute for Science & Technology, Tokyo University of Science
| | - Osamu Sakata
- Research and Development Division, KOSE Corporation
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73
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Role of cationic head-group in cytotoxicity of ionic liquids: Probing changes in bilayer architecture using solid-state NMR spectroscopy. J Colloid Interface Sci 2021; 581:954-963. [DOI: 10.1016/j.jcis.2020.08.115] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/23/2020] [Accepted: 08/28/2020] [Indexed: 01/30/2023]
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74
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Tan L, Elkins JG, Davison BH, Kelley EG, Nickels J. Implementation of a self-consistent slab model of bilayer structure in the SasView suite. J Appl Crystallogr 2021; 54:10.1107/s1600576720015526. [PMID: 37965294 PMCID: PMC10644672 DOI: 10.1107/s1600576720015526] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 11/23/2020] [Indexed: 11/10/2022] Open
Abstract
Slab models are simple and useful structural descriptions which have long been used to describe lyotropic lamellar phases, such as lipid bilayers. Typically, slab models assume a midline symmetry and break a bilayer structure into three pieces, a central solvent-free core and two symmetric outer layers composed of the soluble portion of the amphiphile and associated solvent. This breakdown matches reasonably well to the distribution of neutron scattering length density and therefore is a convenient and common approach for the treatment of small-angle scattering data. Here, an implementation of this model within the SasView software suite is reported. The implementation is intended to provide physical consistency through the area per amphiphile molecule and number of solvent molecules included within the solvent-exposed outer layer. The proper use of this model requires knowledge of (or good estimates for) the amphiphile and solvent molecule volume and atomic composition, ultimately providing a self-consistent data treatment with only two free parameters: the lateral area per amphiphile molecule and the number of solvent molecules included in the outer region per amphiphile molecule. The use of this code is demonstrated in the fitting of standard lipid bilayer data sets, obtaining structural parameters consistent with prior literature and illustrating the typical and ideal cases of fitting for neutron scattering data obtained using single or multiple contrast conditions. While demonstrated here for lipid bilayers, this model is intended for general application to block copolymers, surfactants, and other lyotropic lamellar phase structures for which a slab model is able to reasonably estimate the neutron scattering length density/electron-density profile of inner and outer layers of the lamellae.
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Affiliation(s)
- Luoxi Tan
- Department of Chemical and Environmental Engineering, University of Cincinnati, 2901 Woodside Drive, Cincinnati, OH 45221, USA
| | - James G. Elkins
- Biosciences Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA
| | - Brian H. Davison
- Biosciences Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA
| | - Elizabeth G. Kelley
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersberg, MD 20899, USA
| | - Jonathan Nickels
- Department of Chemical and Environmental Engineering, University of Cincinnati, 2901 Woodside Drive, Cincinnati, OH 45221, USA
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75
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Kiriakidi S, Chatzigiannis C, Papaemmanouil C, Tzakos AG, Cournia Z, Mavromoustakos T. Interplay of cholesterol, membrane bilayers and the AT1R: A cholesterol consensus motif on AT1R is revealed. Comput Struct Biotechnol J 2020; 19:110-120. [PMID: 33384858 PMCID: PMC7758360 DOI: 10.1016/j.csbj.2020.11.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/21/2020] [Accepted: 11/23/2020] [Indexed: 11/18/2022] Open
Abstract
Hypertension, mediated by the Angiotensin II receptor type 1 (AT1R), is still the major cause of premature death despite the discovery of novel therapeutics, highlighting the importance of an in depth understanding of the drug-AT1R recognition mechanisms coupled with the impact of the membrane environment on the interaction of drugs with AT1R. Herein, we examine the interplay of cholesterol-lipid-candesartan and the AT1R using Molecular Dynamics simulations of a model membrane consisting of 60:40 mol%. DPPC:cholesterol, candesartan and the AT1R, mimicking the physiological cholesterol concentration in sarcolemma membranes. The simulations of the model membrane of 60:40 mol%. DPPC:cholesterol were further validated using DOSY NMR experiments. Interestingly, our results suggest a significant role of cholesterol in the AT1R function imposed through a Cholesterol Consensus Motif (CCM) in the receptor, which could be crucial in the drug binding process. Candesartan diffusion towards AT1R through incorporation into lipid bilayers, appears to be retarded by the presence of cholesterol. However, its direct approach towards AT1R may be facilitated through the mobility induced on the N-terminus by the cholesterol binding on the CCM these novel insights could pave the way towards the development of more potent pharmaceutical agents to combat hypertension more effectively.
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Affiliation(s)
- Sofia Kiriakidi
- National and Kapodistrian University of Athens, Department of Chemistry, Athens, Greece
- Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou, 11527 Athens, Greece
| | - Christos Chatzigiannis
- University of Ioannina, Department of Chemistry, Section of Organic Chemistry and Biochemistry, Ioannina, Greece
| | - Christina Papaemmanouil
- University of Ioannina, Department of Chemistry, Section of Organic Chemistry and Biochemistry, Ioannina, Greece
| | - Andreas G. Tzakos
- University of Ioannina, Department of Chemistry, Section of Organic Chemistry and Biochemistry, Ioannina, Greece
| | - Zoe Cournia
- Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou, 11527 Athens, Greece
- Corresponding authors.
| | - Thomas Mavromoustakos
- National and Kapodistrian University of Athens, Department of Chemistry, Athens, Greece
- Corresponding authors.
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76
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Souza LM, Souza FR, Reynaud F, Pimentel AS. Tuning the hydrophobicity of a coarse grained model of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine using the experimental octanol-water partition coefficient. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.114132] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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77
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Fischer M, Luck M, Werle M, Scheidt HA, Müller P. Binding of the small-molecule kinase inhibitor ruxolitinib to membranes does not disturb membrane integrity. Biochem Biophys Rep 2020; 24:100838. [PMID: 33195828 PMCID: PMC7642770 DOI: 10.1016/j.bbrep.2020.100838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 10/08/2020] [Accepted: 10/11/2020] [Indexed: 12/16/2022] Open
Abstract
Ruxolitinib is a small-molecule protein kinase inhibitor, which is used as a therapeutic agent against several diseases. Due to its anti-inflammatory impact, ruxolitinib has also been considered recently for usage in the treatment of Covid-19. While the specific effects of ruxolitinib on Janus kinases (JAK) is comparatively well investigated, its (unspecific) impact on membranes has not been studied in detail so far. Therefore, we characterized the interaction of this drug with lipid membranes employing different biophysical approaches. Ruxolitinib incorporates into the glycerol region of lipid membranes causing an increase in disorder of the lipid chains. This binding, however, has only marginal influence on the structure and integrity of membranes as found by leakage and permeation assays. The drug ruxolitinib binds to lipid membranes. Ruxolitinib intercalates into the glycerol region of the bilayer. The membrane binding of ruxolitinib causes an increased disorder of the lipid chains. The membrane binding of ruxolitinib has no influence on the membrane integrity.
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Affiliation(s)
- Markus Fischer
- Leipzig University, Institute for Medical Physics and Biophysics, Härtelstr. 16-18, D-04107, Leipzig, Germany
| | - Meike Luck
- Humboldt-Universität zu Berlin, Department of Biology, Invalidenstr. 42, D-10115, Berlin, Germany
| | - Maximilian Werle
- Humboldt-Universität zu Berlin, Department of Biology, Invalidenstr. 42, D-10115, Berlin, Germany
| | - Holger A Scheidt
- Leipzig University, Institute for Medical Physics and Biophysics, Härtelstr. 16-18, D-04107, Leipzig, Germany
| | - Peter Müller
- Humboldt-Universität zu Berlin, Department of Biology, Invalidenstr. 42, D-10115, Berlin, Germany
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78
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Engberg O, Bochicchio A, Brandner AF, Gupta A, Dey S, Böckmann RA, Maiti S, Huster D. Serotonin Alters the Phase Equilibrium of a Ternary Mixture of Phospholipids and Cholesterol. Front Physiol 2020; 11:578868. [PMID: 33192582 PMCID: PMC7645218 DOI: 10.3389/fphys.2020.578868] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/06/2020] [Indexed: 12/20/2022] Open
Abstract
Unsaturated and saturated phospholipids tend to laterally segregate, especially in the presence of cholesterol. Small molecules such as neurotransmitters, toxins, drugs etc. possibly modulate this lateral segregation. The small aromatic neurotransmitter serotonin (5-HT) has been found to bind to membranes. We studied the lipid structure and packing of a ternary membrane mixture consisting of palmitoyl-oleoyl-phosphatidylcholine, palmitoyl-sphingomyelin, and cholesterol at a molar ratio of 4/4/2 in the absence and in the presence of 5-HT, using a combination of solid-state 2H NMR, atomic force microscopy, and atomistic molecular dynamics (MD) simulations. Both NMR and MD report formation of a liquid ordered (L o ) and a liquid disordered (L d ) phase coexistence with small domains. Lipid exchange between the domains was fast such that single component 2H NMR spectra are detected over a wide temperature range. A drastic restructuring of the domains was induced when 5-HT is added to the membranes at a 9 mol% concentration relative to the lipids. 2H NMR spectra of all components of the mixture showed two prominent contributions indicative of molecules of the same kind residing both in the disordered and the ordered phase. Compared to the data in the absence of 5-HT, the lipid chain order in the disordered phase was further decreased in the presence of 5-HT. Likewise, addition of serotonin increased lipid chain order within the ordered phase. These characteristic lipid chain order changes were confirmed by MD simulations. The 5-HT-induced larger difference in lipid chain order results in more pronounced differences in the hydrophobic thickness of the individual membrane domains. The correspondingly enlarged hydrophobic mismatch between ordered and disordered phases is assumed to increase the line tension at the domain boundary, which drives the system into formation of larger size domains. These results not only demonstrate that small membrane binding molecules such as neurotransmitters have a profound impact on essential membrane properties. It also suggests a mechanism by which the interaction of small molecules with membranes can influence the function of membrane proteins and non-cognate receptors. Altered membrane properties may modify lateral sorting of membrane protein, membrane protein conformation, and thus influence their function as suspected for neurotransmitters, local anesthetics, and other small drug molecules.
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Affiliation(s)
- Oskar Engberg
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Anna Bochicchio
- Computational Biology, Department of Biology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Astrid F. Brandner
- Computational Biology, Department of Biology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Ankur Gupta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Simli Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Rainer A. Böckmann
- Computational Biology, Department of Biology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
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79
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Mondal D, Malik S, Banerjee P, Kundu N, Debnath A, Sarkar N. Modulation of Membrane Fluidity to Control Interfacial Water Structure and Dynamics in Saturated and Unsaturated Phospholipid Vesicles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:12423-12434. [PMID: 33035065 DOI: 10.1021/acs.langmuir.0c02736] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The structure and dynamics of interfacial water in biological systems regulate the biochemical reactions. But, it is still enigmatic how the behavior of the interfacial water molecule is controlled. Here, we have investigated the effect of membrane fluidity on the structure and dynamics of interfacial water molecules in biologically relevant phopholipid vesicles. This study delineates that modulation of membrane fluidity through interlipid separation and unsaturation not only mitigate membrane rigidity but also disrupt the strong hydrogen bond (H-bond) network around the lipid bilayer interface. As a result, a disorder in H-bonding between water molecules arises several layers beyond the first hydration shell of the polar headgroup, which essentially modifies the interfacial water structure and dynamics. Furthermore, we have also provided evidence of increasing transportation through these modulated membranes, which enhance the membrane mediated isomerization reaction rate.
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Affiliation(s)
- Dipankar Mondal
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302, West Bengal, India
| | - Sheeba Malik
- Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur 342037, Rajasthan, India
| | - Pavel Banerjee
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302, West Bengal, India
| | - Niloy Kundu
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302, West Bengal, India
- Environment Research Group, R&D and Scientific Services Department, Tata Steel Ltd., Jamshedpur 831007, India
| | - Ananya Debnath
- Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur 342037, Rajasthan, India
| | - Nilmoni Sarkar
- Department of Chemistry, Indian Institute of Technology Kharagpur Kharagpur 721302, West Bengal, India
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80
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Tsuchikawa H, Ono T, Yamagami M, Umegawa Y, Shinoda W, Murata M. Conformation and Orientation of Branched Acyl Chains Responsible for the Physical Stability of Diphytanoylphosphatidylcholine. Biochemistry 2020; 59:3929-3938. [PMID: 32945657 DOI: 10.1021/acs.biochem.0c00589] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Diphytanoylphosphatidylcholine (DPhPC) is a synthetic phospholipid in which two methyl-branched acyl chains are introduced into the glycerol moiety, mimicking phospholipids of eukaryotic and eubacterial origins. The lipid bilayers of DPhPC reproduce the outstanding physical properties of methyl-branched lipids that occur in archaeal membranes. DPhPC is commonly used as the base lipid in biophysical experiments, particularly for recording ion-channel currents. However, the dynamics of lipid molecules that induces their useful physical properties is still unclear. In this study, we examined the conformation and orientation of the methyl-branched acyl chain of DPhPC in a membrane using 2H nuclear magnetic resonance (NMR) measurements of the synthetic lipid with a high stereochemical purity and molecular dynamics (MD) simulations. Deuterium-labeled 3',3'-CD3,D-DPhPC (2) and 7',7'-CD3,D-DPhPC (3) showed the characteristic quadrupole splitting width in the 2H NMR spectra, which corresponded to the bent orientation reported for the archaeal lipid PGP-Me [Yamagami, M., et al. (2019) Biochemistry 58, 3869-3879]. However, MD simulations, which reproduced the 2H NMR results well, unveiled the unknown features of DPhPC in the membrane; DPhPC has a chain-specific average orientation, where two bent orientations with upward and downward methyl groups occur at positions C3 and C7 of the sn-1 and sn-2 chains of DPhPC, respectively. These MD and NMR results reveal that these two bent orientations define the average orientation of DPhPC for the shallow part of the acyl chains, which is considered to be an important factor in the stability of DPhPC membranes.
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Affiliation(s)
- Hiroshi Tsuchikawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,Department of Clinical Pharmacology and Therapeutics, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593, Japan
| | - Takuya Ono
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Masaki Yamagami
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,JST ERATO, Lipid Active Structure Project and Project Research Center for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Yuichi Umegawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,JST ERATO, Lipid Active Structure Project and Project Research Center for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Wataru Shinoda
- Department of Materials Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,JST ERATO, Lipid Active Structure Project and Project Research Center for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
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81
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Tian L, Wu G. Microsecond molecular dynamics simulation of the adsorption and penetration of oil droplets on cellular membrane. JOURNAL OF HAZARDOUS MATERIALS 2020; 397:122683. [PMID: 32447203 DOI: 10.1016/j.jhazmat.2020.122683] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/15/2020] [Accepted: 04/07/2020] [Indexed: 06/11/2023]
Abstract
The hazardous effects of petroleum contaminants in the soil and water environment are highly associated with their interactions with cellular membranes, but our understanding on the molecular-level mechanisms for the adsorption and penetration of heavy oil mixture on cellular membrane is very limited. In this study, microsecond molecular dynamics simulations were performed to gain insights into the morphological evolution and penetration dynamics of the multi-component and single-component oil droplets on the dipalmitoylphosphatidylcholine lipid membrane. Results highlighted the inhibition effect of the resins on the penetration of alkanes and aromatics, because they would form net structure making it difficult to release the latter two components from the oil droplet to the membrane. It also demonstrated the obviously different patterns of penetration between alkanes and aromatics. The overall steps for the toluene penetration included detachment from oil droplet, dispersion in water, adsorption on membrane surface, structure adjustment and penetration into membrane. By contrast, the step of dispersion in water was not necessary for the alkanes' penetration. Instead, it relied on the adsorption of the whole oil droplet on the membrane surface which resulted in the formation of pores on the membrane surface by local structure deformation in the lipid head group regions.
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Affiliation(s)
- Linqing Tian
- Division of Ocean Science and Technology, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China; School of Environment, Tsinghua University, Beijing, 100084, China
| | - Guozhong Wu
- Division of Ocean Science and Technology, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China; School of Environment, Tsinghua University, Beijing, 100084, China.
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82
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Kinnun JJ, Bolmatov D, Lavrentovich MO, Katsaras J. Lateral heterogeneity and domain formation in cellular membranes. Chem Phys Lipids 2020; 232:104976. [PMID: 32946808 PMCID: PMC7491465 DOI: 10.1016/j.chemphyslip.2020.104976] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 12/17/2022]
Abstract
As early as the development of the fluid mosaic model for cellular membranes, researchers began observing the telltale signs of lateral heterogeneity. Over the decades this has led to the development of the lipid raft hypothesis and the ensuing controversy that has unfolded, as a result. Here, we review the physical concepts behind domain formation in lipid membranes, both of their structural and dynamic origins. This, then leads into a discussion of coarse-grained, phenomenological approaches that describe the wide range of phases associated with lipid lateral heterogeneity. We use these physical concepts to describe the interaction between raft-lipid species, such as long-chain saturated lipids, sphingomyelin, and cholesterol, and non-raft forming lipids, such as those with short acyl chains or unsaturated fatty acids. While debate has persisted on the biological relevance of lipid domains, recent research, described here, continues to identify biological roles for rafts and new experimental approaches have revealed the existence of lipid domains in living systems. Given the recent progress on both the biological and structural aspects of raft formation, the research area of membrane lateral heterogeneity will not only expand, but will continue to produce exciting results.
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Affiliation(s)
- Jacob J Kinnun
- Large Scale Structures Group, Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States; Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
| | - Dima Bolmatov
- Large Scale Structures Group, Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States; Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States; Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States.
| | - Maxim O Lavrentovich
- Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States; Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States.
| | - John Katsaras
- Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States; Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States; Sample Environment Group, Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
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83
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Engberg O, Kováčik A, Pullmannová P, Juhaščik M, Opálka L, Huster D, Vávrová K. The Sphingosine and Acyl Chains of Ceramide [NS] Show Very Different Structure and Dynamics That Challenge Our Understanding of the Skin Barrier. Angew Chem Int Ed Engl 2020; 59:17383-17387. [PMID: 32515145 PMCID: PMC7540555 DOI: 10.1002/anie.202003375] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/22/2020] [Indexed: 12/28/2022]
Abstract
The lipid phase of the uppermost human skin layer is thought to comprise highly rigid lipids in an orthorhombic phase state to protect the body against the environment. By synthesizing sphingosine-d28 deuterated N-lignoceroyl-d-erythro-sphingosine (ceramide [NS]), we compare the structure and dynamics of both chains of that lipid in biologically relevant mixtures using X-ray diffraction, 2 H NMR analysis, and infrared spectroscopy. Our results reveal a substantial fraction of sphingosine chains in a fluid and dynamic phase state at physiological temperature. These findings prompt revision of our current understanding of the skin lipid barrier, where an extended ceramide [NS] conformation is preferred and a possible domain structure is proposed. Mobile lipid chains may be crucial for skin elasticity and the translocation of physiologically important molecules.
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Affiliation(s)
- Oskar Engberg
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804275LeipzigGermany
| | - Andrej Kováčik
- Skin Barrier Research GroupFaculty of Pharmacy in Hradec KrálovéCharles UniversityAkademika Heyrovského 120350005Hradec KrálovéCzech Republic
| | - Petra Pullmannová
- Skin Barrier Research GroupFaculty of Pharmacy in Hradec KrálovéCharles UniversityAkademika Heyrovského 120350005Hradec KrálovéCzech Republic
| | - Martin Juhaščik
- Skin Barrier Research GroupFaculty of Pharmacy in Hradec KrálovéCharles UniversityAkademika Heyrovského 120350005Hradec KrálovéCzech Republic
| | - Lukáš Opálka
- Skin Barrier Research GroupFaculty of Pharmacy in Hradec KrálovéCharles UniversityAkademika Heyrovského 120350005Hradec KrálovéCzech Republic
| | - Daniel Huster
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804275LeipzigGermany
- Department of Chemical ScienceTata Institute of Fundamental ResearchDr. Homi Bhabha Road, ColabaMumbai400 005India
| | - Kateřina Vávrová
- Skin Barrier Research GroupFaculty of Pharmacy in Hradec KrálovéCharles UniversityAkademika Heyrovského 120350005Hradec KrálovéCzech Republic
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84
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Kremkow J, Luck M, Huster D, Müller P, Scheidt HA. Membrane Interaction of Ibuprofen with Cholesterol-Containing Lipid Membranes. Biomolecules 2020; 10:biom10101384. [PMID: 32998467 PMCID: PMC7650631 DOI: 10.3390/biom10101384] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/25/2020] [Accepted: 09/26/2020] [Indexed: 12/14/2022] Open
Abstract
Deciphering the membrane interaction of drug molecules is important for improving drug delivery, cellular uptake, and the understanding of side effects of a given drug molecule. For the anti-inflammatory drug ibuprofen, several studies reported contradictory results regarding the impact of ibuprofen on cholesterol-containing lipid membranes. Here, we investigated membrane localization and orientation as well as the influence of ibuprofen on membrane properties in POPC/cholesterol bilayers using solid-state NMR spectroscopy and other biophysical assays. The presence of ibuprofen disturbs the molecular order of phospholipids as shown by alterations of the 2H and 31P-NMR spectra of the lipids, but does not lead to an increased membrane permeability or changes of the phase state of the bilayer. 1H MAS NOESY NMR results demonstrate that ibuprofen adopts a mean position in the upper chain/glycerol region of the POPC membrane, oriented with its polar carbonyl group towards the aqueous phase. This membrane position is only marginally altered in the presence of cholesterol. A previously reported result that ibuprofen is expelled from the membrane interface in cholesterol-containing DMPC bilayers could not be confirmed.
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Affiliation(s)
- Jan Kremkow
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany; (J.K.); (D.H.)
| | - Meike Luck
- Department of Biology, Humboldt University Berlin, Invalidenstr. 42, D-10115 Berlin, Germany; (M.L.); (P.M.)
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany; (J.K.); (D.H.)
| | - Peter Müller
- Department of Biology, Humboldt University Berlin, Invalidenstr. 42, D-10115 Berlin, Germany; (M.L.); (P.M.)
| | - Holger A. Scheidt
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany; (J.K.); (D.H.)
- Correspondence:
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85
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Engberg O, Kováčik A, Pullmannová P, Juhaščik M, Opálka L, Huster D, Vávrová K. Die unterschiedliche Struktur und Dynamik der Sphingosin‐ und Acylketten von Ceramid [NS] verändern unser Verständnis der Struktur der Hautbarriere. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202003375] [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)
- Oskar Engberg
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstraße 16–18 04275 Leipzig Deutschland
| | - Andrej Kováčik
- Skin Barrier Research Group Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 50005 Hradec Králové Czech Republi
| | - Petra Pullmannová
- Skin Barrier Research Group Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 50005 Hradec Králové Czech Republi
| | - Martin Juhaščik
- Skin Barrier Research Group Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 50005 Hradec Králové Czech Republi
| | - Lukáš Opálka
- Skin Barrier Research Group Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 50005 Hradec Králové Czech Republi
| | - Daniel Huster
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstraße 16–18 04275 Leipzig Deutschland
- Department of Chemical Science Tata Institute of Fundamental Research Dr. Homi Bhabha Road, Colaba Mumbai 400 005 Indien
| | - Kateřina Vávrová
- Skin Barrier Research Group Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 50005 Hradec Králové Czech Republi
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86
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Grote F, Lyubartsev AP. Optimization of Slipids Force Field Parameters Describing Headgroups of Phospholipids. J Phys Chem B 2020; 124:8784-8793. [PMID: 32926619 PMCID: PMC7584372 DOI: 10.1021/acs.jpcb.0c06386] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The molecular mechanics force field Slipids developed in a series of works by Jämbeck and Lyubartsev (J. Phys. Chem. B 2012, 116, 3164-3179; J. Chem. Theory Comput. 2012, 8, 2938-2948) generally provides a good description of various lipid bilayer systems. However, it was also found that order parameters of C-H bonds in the glycerol moiety of the phosphatidylcholine headgroup deviate significantly from NMR results. In this work, the dihedral force field parameters have been reparameterized in order to improve the agreement with experiment. For this purpose, we have computed energies for a large amount of lipid headgroup conformations using density functional theory on the B3P86/cc-pvqz level and optimized dihedral angle parameters simultaneously to provide the best fit to the quantum chemical energies. The new parameter set was validated for three lipid bilayer systems against a number of experimental properties including order parameters, area per lipid, scattering form factors, bilayer thickness, area compressibility and lateral diffusion coefficients. In addition, the order parameter dependence on cholesterol content in the POPC bilayer was investigated. It is shown that the new force field significantly improves agreement with the experimental order parameters for the lipid headgroup while keeping good agreement with other experimentally measured properties.
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Affiliation(s)
- Fredrik Grote
- Department of Materials and Environmental Chemistry, Stockholm University, SE 106 91, Stockholm, Sweden
| | - Alexander P Lyubartsev
- Department of Materials and Environmental Chemistry, Stockholm University, SE 106 91, Stockholm, Sweden
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87
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Kelley EG, Butler PD, Ashkar R, Bradbury R, Nagao M. Scaling relationships for the elastic moduli and viscosity of mixed lipid membranes. Proc Natl Acad Sci U S A 2020; 117:23365-23373. [PMID: 32883879 PMCID: PMC7519290 DOI: 10.1073/pnas.2008789117] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The elastic and viscous properties of biological membranes play a vital role in controlling cell functions that require local reorganization of the membrane components as well as dramatic shape changes such as endocytosis, vesicular trafficking, and cell division. These properties are widely acknowledged to depend on the unique composition of lipids within the membrane, yet the effects of lipid mixing on the membrane biophysical properties remain poorly understood. Here, we present a comprehensive characterization of the structural, elastic, and viscous properties of fluid membranes composed of binary mixtures of lipids with different tail lengths. We show that the mixed lipid membrane properties are not simply additive quantities of the single-component analogs. Instead, the mixed membranes are more dynamic than either of their constituents, quantified as a decrease in their bending modulus, area compressibility modulus, and viscosity. While the enhanced dynamics are seemingly unexpected, we show that the measured moduli and viscosity for both the mixed and single-component bilayers all scale with the area per lipid and collapse onto respective master curves. This scaling links the increase in dynamics to mixing-induced changes in the lipid packing and membrane structure. More importantly, the results show that the membrane properties can be manipulated through lipid composition the same way bimodal blends of surfactants, liquid crystals, and polymers are used to engineer the mechanical properties of soft materials, with broad implications for understanding how lipid diversity relates to biomembrane function.
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Affiliation(s)
- Elizabeth G Kelley
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899;
| | - Paul D Butler
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716
- Department of Chemistry, The University of Tennessee, Knoxville, TN 37996
| | - Rana Ashkar
- Physics Department, Virginia Tech, Blacksburg, VA 20461
- Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA 20461
| | - Robert Bradbury
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899
- Center for Exploration of Energy and Matter, Indiana University, Bloomington, IN 47408
| | - Michihiro Nagao
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899
- Center for Exploration of Energy and Matter, Indiana University, Bloomington, IN 47408
- Department of Physics and Astronomy, University of Delaware, Newark, DE 19716
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88
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Schlame M. Protein crowding in the inner mitochondrial membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148305. [PMID: 32916174 DOI: 10.1016/j.bbabio.2020.148305] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/24/2020] [Accepted: 09/03/2020] [Indexed: 10/23/2022]
Abstract
The inner membrane of mitochondria is known for its low lipid-to-protein ratio. Calculations based on the size and the concentration of the principal membrane components, suggest about half of the hydrophobic volume of the membrane is occupied by proteins. Such high degree of crowding is expected to strain the hydrophobic coupling between proteins and lipids unless stabilizing mechanisms are in place. Both protein supercomplexes and cardiolipin are likely to be critical for the integrity of the inner mitochondrial membrane because they reduce the energy penalty of crowding.
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Affiliation(s)
- Michael Schlame
- Departments of Anesthesiology and Cell Biology, New York University School of Medicine, NY 10016, USA.
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89
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Nagarajan S, Babu S, Sohn H, Madhavan T. Molecular-Level Understanding of the Somatostatin Receptor 1 (SSTR1)-Ligand Binding: A Structural Biology Study Based on Computational Methods. ACS OMEGA 2020; 5:21145-21161. [PMID: 32875251 PMCID: PMC7450625 DOI: 10.1021/acsomega.0c02847] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Somatostatin receptor 1 (SSTR1), a subtype of somatostatin receptors, is involved in various signaling mechanisms in different parts of the human body. Like most of the G-protein-coupled receptors (GPCRs), the available information on the structural features of SSTR1 responsible for the biological activity is scarce. In this study, we report a molecular-level understanding of SSTR1-ligand binding, which could be helpful in solving the structural complexities involved in SSTR1 functioning. Based on a three-dimensional quantitative structure-activity relationship (3D-QSAR) study using comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA), we have identified that an electronegative, less-bulkier, and hydrophobic atom substitution can substantially increase the biological activity of SSTR1 ligands. A density functional theory (DFT) study has been followed to study the electron-related properties of the SSTR1 ligands and to validate the results obtained via the 3D-QSAR study. 3D models of SSTR1-ligand systems have been embedded in lipid-lipid bilayer membranes to perform molecular dynamics (MD) simulations. Analysis of the MD trajectories reveals important information about the crucial residues involved in SSTR1-ligand binding and various conformational changes in the protein that occur after ligand binding. Additionally, we have identified the probable ligand-binding site of SSTR1 and validated it using MD. We have also studied the favorable conditions that are essential for forming the most stable and lowest-energy bioactive conformation of the ligands inside the binding site. The results of the study could be useful in constructing more potent and novel SSTR1 antagonists and agonists.
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Affiliation(s)
- Santhosh
Kumar Nagarajan
- Computational
Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai 603203, India
| | - Sathya Babu
- Computational
Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai 603203, India
| | - Honglae Sohn
- Department
of Chemistry and Department of Carbon Materials, Chosun University, Gwangju, South Korea
| | - Thirumurthy Madhavan
- Computational
Biology Lab, Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Chennai 603203, India
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90
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Abstract
Cholesterol is an integral component of eukaryotic cell membranes and a key molecule in controlling membrane fluidity, organization, and other physicochemical parameters. It also plays a regulatory function in antibiotic drug resistance and the immune response of cells against viruses, by stabilizing the membrane against structural damage. While it is well understood that, structurally, cholesterol exhibits a densification effect on fluid lipid membranes, its effects on membrane bending rigidity are assumed to be nonuniversal; i.e., cholesterol stiffens saturated lipid membranes, but has no stiffening effect on membranes populated by unsaturated lipids, such as 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). This observation presents a clear challenge to structure-property relationships and to our understanding of cholesterol-mediated biological functions. Here, using a comprehensive approach-combining neutron spin-echo (NSE) spectroscopy, solid-state deuterium NMR (2H NMR) spectroscopy, and molecular dynamics (MD) simulations-we report that cholesterol locally increases the bending rigidity of DOPC membranes, similar to saturated membranes, by increasing the bilayer's packing density. All three techniques, inherently sensitive to mesoscale bending fluctuations, show up to a threefold increase in effective bending rigidity with increasing cholesterol content approaching a mole fraction of 50%. Our observations are in good agreement with the known effects of cholesterol on the area-compressibility modulus and membrane structure, reaffirming membrane structure-property relationships. The current findings point to a scale-dependent manifestation of membrane properties, highlighting the need to reassess cholesterol's role in controlling membrane bending rigidity over mesoscopic length and time scales of important biological functions, such as viral budding and lipid-protein interactions.
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91
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Horne JE, Brockwell DJ, Radford SE. Role of the lipid bilayer in outer membrane protein folding in Gram-negative bacteria. J Biol Chem 2020; 295:10340-10367. [PMID: 32499369 PMCID: PMC7383365 DOI: 10.1074/jbc.rev120.011473] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 06/03/2020] [Indexed: 01/09/2023] Open
Abstract
β-Barrel outer membrane proteins (OMPs) represent the major proteinaceous component of the outer membrane (OM) of Gram-negative bacteria. These proteins perform key roles in cell structure and morphology, nutrient acquisition, colonization and invasion, and protection against external toxic threats such as antibiotics. To become functional, OMPs must fold and insert into a crowded and asymmetric OM that lacks much freely accessible lipid. This feat is accomplished in the absence of an external energy source and is thought to be driven by the high thermodynamic stability of folded OMPs in the OM. With such a stable fold, the challenge that bacteria face in assembling OMPs into the OM is how to overcome the initial energy barrier of membrane insertion. In this review, we highlight the roles of the lipid environment and the OM in modulating the OMP-folding landscape and discuss the factors that guide folding in vitro and in vivo We particularly focus on the composition, architecture, and physical properties of the OM and how an understanding of the folding properties of OMPs in vitro can help explain the challenges they encounter during folding in vivo Current models of OMP biogenesis in the cellular environment are still in flux, but the stakes for improving the accuracy of these models are high. OMP folding is an essential process in all Gram-negative bacteria, and considering the looming crisis of widespread microbial drug resistance it is an attractive target. To bring down this vital OMP-supported barrier to antibiotics, we must first understand how bacterial cells build it.
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Affiliation(s)
- Jim E Horne
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - David J Brockwell
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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92
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Haralampiev I, Alonso de Armiño DJ, Luck M, Fischer M, Abel T, Huster D, Di Lella S, Scheidt HA, Müller P. Interaction of the small-molecule kinase inhibitors tofacitinib and lapatinib with membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183414. [PMID: 32710852 DOI: 10.1016/j.bbamem.2020.183414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 07/09/2020] [Accepted: 07/12/2020] [Indexed: 12/31/2022]
Abstract
Lapatinib and tofacitinib are small-molecule kinase inhibitors approved for the treatment of advanced or metastatic breast cancer and rheumatoid arthritis, respectively. So far, the mechanisms which are responsible for their activities are not entirely understood. Here, we focus on the interaction of these drug molecules with phospholipid membranes, which has not yet been investigated before in molecular detail. Owing to their lipophilic characteristics, quantitatively reflected by large differences of the partition equilibrium between water and octanol phases (expressed by logP values), rather drastic differences in the membrane interaction of both molecules have to be expected. Applying experimental (nuclear magnetic resonance, fluorescence and ESR spectroscopy) and theoretical (molecular dynamics simulations) approaches, we found that lapatinib and tofacitinib bind to lipid membranes and insert into the lipid-water interface of the bilayer. For lapatinib, a deeper embedding into the membrane bilayer was observed than for tofacitinib implying different impacts of the molecules on the bilayer structure. While for tofacitinib, no influence to the membrane structure was found, lapatinib causes a membrane disturbance, as concluded from an increased permeability of the membrane for polar molecules. These data may contribute to a better understanding of the cellular uptake mechanism(s) and the side effects of the drugs.
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Affiliation(s)
- Ivan Haralampiev
- Humboldt-Universität zu Berlin, Department of Biology, Invalidenstr. 42, D-10115 Berlin, Germany
| | - Diego Javier Alonso de Armiño
- Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. II, C1428EHA Buenos Aires, Argentina
| | - Meike Luck
- Humboldt-Universität zu Berlin, Department of Biology, Invalidenstr. 42, D-10115 Berlin, Germany
| | - Markus Fischer
- Leipzig University, Institute for Medical Physics and Biophysics, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Tobias Abel
- Leipzig University, Institute for Medical Physics and Biophysics, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Daniel Huster
- Leipzig University, Institute for Medical Physics and Biophysics, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Santiago Di Lella
- Instituto de Química Biológica - Ciencias Exactas y Naturales (IQUIBICEN) Conicet - Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. II, C1428EHA Ciudad de Buenos Aires, Argentina.
| | - Holger A Scheidt
- Leipzig University, Institute for Medical Physics and Biophysics, Härtelstr. 16-18, D-04107 Leipzig, Germany.
| | - Peter Müller
- Humboldt-Universität zu Berlin, Department of Biology, Invalidenstr. 42, D-10115 Berlin, Germany.
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93
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Ledum M, Løland Bore S, Cascella M. Automated determination of hybrid particle-field parameters by machine learning. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1785571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Morten Ledum
- Department of Chemistry and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, Oslo, Norway
| | - Sigbjørn Løland Bore
- Department of Chemistry and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, Oslo, Norway
| | - Michele Cascella
- Department of Chemistry and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, Oslo, Norway
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94
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Faulkner C, Santos-Carballal D, Plant DF, de Leeuw NH. Atomistic Molecular Dynamics Simulations of Propofol and Fentanyl in Phosphatidylcholine Lipid Bilayers. ACS OMEGA 2020; 5:14340-14353. [PMID: 32596571 PMCID: PMC7315410 DOI: 10.1021/acsomega.0c00813] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
Atomistic molecular dynamics (MD) and steered MD simulations in combination with umbrella sampling methodology were utilized to study the general anesthetic propofol and the opioid analgesic fentanyl and their interaction with lipid bilayers, which is not yet fully understood. These molecules were inserted into two different fully hydrated phospholipid bilayers, namely, dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC), to investigate the effects that these drugs have on the bilayer. We determined the role of the lipid chain length and saturation on the behavior of the two drugs. Pure, fully hydrated DOPC and DPPC bilayers were also simulated, and the results were in excellent agreement with the experimental values. Various structural and mechanical properties of each system, such as the area per lipid, area compressibility modulus, order parameter, lateral lipid diffusion, hydrogen bonds, and radial distribution functions, have been calculated to assess how the drug molecules affect the different bilayers. From the calculated results, we show that fentanyl and propofol generally follow similar trends in each bilayer but adopt different favorable positions close to the headgroup/chain interface at the carbonyl groups. Propofol was shown to selectively form hydrogen bonds at the carbonyl carbon in each bilayer, whereas fentanyl interacts with water molecules at the headgroup interface. From the calculated free-energy profiles, we determined that both molecules show a preference for the low-density, low-order acyl chain region of the bilayers and both significantly preferred the DOPC bilayer with propofol and fentanyl having energy minima at -6.66 and -43.07 kcal mol-1, respectively. This study suggests that different chain lengths and levels of saturation directly affect the properties of these two important molecules, which are seen to work together to control anesthesia in surgical applications.
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Affiliation(s)
- Christopher Faulkner
- School
of Chemistry, Cardiff University, Main Building, Park Place, CF10 3AT Cardiff, U.K.
| | - David Santos-Carballal
- School
of Chemistry, Cardiff University, Main Building, Park Place, CF10 3AT Cardiff, U.K.
- School
of Chemistry, University of Leeds, Leeds LS2 9JT, U.K.
| | | | - Nora H. de Leeuw
- School
of Chemistry, Cardiff University, Main Building, Park Place, CF10 3AT Cardiff, U.K.
- School
of Chemistry, University of Leeds, Leeds LS2 9JT, U.K.
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95
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Ramezanpour M, Schmidt ML, Bashe BYM, Pruim JR, Link ML, Cullis PR, Harper PE, Thewalt JL, Tieleman DP. Structural Properties of Inverted Hexagonal Phase: A Hybrid Computational and Experimental Approach. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:6668-6680. [PMID: 32437159 DOI: 10.1021/acs.langmuir.0c00600] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Inverted/reverse hexagonal (HII) phases are of special interest in several fields of research, including nanomedicine. We used molecular dynamics (MD) simulation to study HII systems composed of dioleoylphosphatidylethanolamine (DOPE) and palmitoyloleoylphosphatidylethanolamine (POPE) at several hydration levels and temperatures. The effect of the hydration level on several HII structural parameters, including deuterium order parameters, was investigated. We further used MD simulations to estimate the maximum hydrations of DOPE and POPE HII lattices at several given temperatures. Finally, the effect of acyl chain unsaturation degree on the HII structure was studied via comparing the DOPE with POPE HII systems. In addition to MD simulations, we used deuterium nuclear magnetic resonance (2H NMR) and small-angle X-ray scattering (SAXS) experiments to measure the DOPE acyl chain order parameters, lattice plane distances, and the water core radius in HII phase DOPE samples at several temperatures in the presence of excess water. Structural parameters calculated from MD simulations are in excellent agreement with the experimental data. Dehydration decreases the radius of the water core. An increase in hydration level slightly increased the deuterium order parameter of lipids acyl chains, whereas an increase in temperature decreased it. Lipid cylinders undulated along the cylinder axis as a function of hydration level. The maximum hydration levels of PE HII phases at different temperatures were successfully predicted by MD simulations based on a single experimental measurement for the lattice plane distance in the presence of excess water. An increase in temperature decreases the maximum hydration and consequently the radius of the water core and lattice plane distances. Finally, DOPE formed HII structures with a higher curvature compared to POPE, as expected. We propose a general protocol for constructing computational HII systems that correspond to the experimental systems. This protocol could be used to study HII systems composed of molecules other than the PE systems used here and to improve and validate force field parameters by using the target data in the HII phase.
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Affiliation(s)
- M Ramezanpour
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - M L Schmidt
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - B Y M Bashe
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - J R Pruim
- Department of Physics and Astronomy, Calvin University, Grand Rapids, Michigan 49546, United States
| | - M L Link
- Department of Physics and Astronomy, Calvin University, Grand Rapids, Michigan 49546, United States
| | - P R Cullis
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - P E Harper
- Department of Physics and Astronomy, Calvin University, Grand Rapids, Michigan 49546, United States
| | - J L Thewalt
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- Department of Physics, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - D P Tieleman
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
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96
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Venkatraman RK, Baiz CR. Ultrafast Dynamics at the Lipid-Water Interface: DMSO Modulates H-Bond Lifetimes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:6502-6511. [PMID: 32423219 DOI: 10.1021/acs.langmuir.0c00870] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Dimethyl sulfoxide (DMSO) is a common cosolvent and cryopreservation agent used to freeze cells and tissues. DMSO alters the H-bond structure of water, but its interactions with biomolecules and, specifically, with biological interfaces remain poorly understood. Here we investigate the effects of DMSO on the H-bond dynamics at the lipid-water interface using a combination of ultrafast two-dimensional infrared (2D IR) spectroscopy and molecular dynamics simulations. Ester carbonyl absorption spectra show that DMSO dehydrates the interface, and simulations show that the area per lipid is decreased. Ultrafast 2D IR spectra measure the time scales of frequency fluctuations at the ester carbonyl positions located precisely between the hydrophobic and hydrophilic regions of the membrane. 2D IR measurements show that low DMSO concentrations (<10 mol %) induce ∼40% faster H-bond dynamics compared with pure water, whereas increased concentrations (>10-20 mol %) once again slow down the dynamics. This slow-fast-slow trend is described in terms of two different solvation regimes. Below 10 mol %, DMSO weakens the interfacial H bond, leading to faster "bulk-like" dynamics, whereas above 10 mol %, water molecules become "relatively immobilized" as the H-bond networks becoming disrupted by the H-bond donor/acceptor imbalance at the interface. These studies are an important step toward characterizing the environments around lipid membranes, which are essential to numerous biological processes.
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Affiliation(s)
- Ravi Kumar Venkatraman
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Carlos R Baiz
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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97
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Ridolfi A, Caselli L, Montis C, Mangiapia G, Berti D, Brucale M, Valle F. Gold nanoparticles interacting with synthetic lipid rafts: an AFM investigation. J Microsc 2020; 280:194-203. [PMID: 32432336 DOI: 10.1111/jmi.12910] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 12/30/2022]
Abstract
Inorganic nanoparticles (NPs) represent promising examples of engineered nanomaterials, providing interesting biomedical solutions in several fields, like therapeutics and diagnostics. Despite the extensive number of investigations motivated by their remarkable potential for nanomedicinal applications, the interactions of NPs with biological interfaces are still poorly understood. The effect of NPs on living organisms is mediated by biological barriers, such as the cell plasma membrane, whose lateral heterogeneity is thought to play a prominent role in NPs adsorption and uptake pathways. In particular, biological membranes feature the presence of rafts, that is segregated lipid micro and/or nanodomains in the so-called liquid ordered phase (Lo ), immiscible with the surrounding liquid disordered phase (Ld ). Rafts are involved in various biological functions and act as sites for the selective adsorption of materials on the membrane. Indeed, the thickness mismatch present along their boundaries generates energetically favourable conditions for the adsorption of NPs. Despite its clear implications in NPs internalisation processes and cytotoxicity, a direct proof of the selective adsorption of NPs along the rafts' boundaries is still missing to date. Here we use multicomponent supported lipid bilayers (SLBs) as reliable synthetic models, reproducing the nanometric lateral heterogeneity of cell membranes. After being characterised by atomic force microscopy (AFM) and neutron reflectivity (NR), multidomain SLBs are challenged by prototypical inorganic nanoparticles, that is citrated gold nanoparticles (AuNPs), under simplified and highly controlled conditions. By exploiting AFM, we demonstrate that AuNPs preferentially target lipid phase boundaries as adsorption sites. The herein reported study consolidates and extends the fundamental knowledge on NPs-membrane interactions, which constitute a key aspect to consider when designing NPs-related biomedical applications. LAY DESCRIPTION: Inorganic nanoparticles (NPs) represent promising examples of engineered nanomaterials, offering interesting biomedical solutions in multiple fields like therapeutics and diagnostics. Despite being extensively investigated due to their remarkable potential for nanomedicinal applications, the interaction of NPs with biological systems is in several cases still poorly understood. The interaction of NPs with living organisms is mediated by biological barriers, such as the cell plasma membrane. Supported lipid bilayers (SLBs) represent suitable synthetic membrane models for studying the physicochemical properties of natural interfaces and their interaction with inorganic nanomaterials under simplified and controlled conditions. Recently, multicomponent SLBs were developed in order to mimic the lateral heterogeneity of most biological membranes. In particular, biological membranes feature the presence of rafts, that is segregated lipid micro and/or nanodomains, enriched in cholesterol, sphingomyelin, saturated glycerophospholipids and glycosphingolipids: these lipids segregate in the so-called liquid-ordered phase (Lo ), characterised by a high molecular packing degree, which promotes the phase separation from the surrounding liquid-crystalline (disordered, Ld ) phase, where the intermolecular mobility is increased. Rafts are thought to participate in the formation and targeting of nano-sized biogenic lipid vesicles and are also actively involved in multiple membrane processes. Indeed, Lo -Ld phase boundaries represent high energy areas, providing active sites for the preferential adsorption of external material. The selective adsorption of NPs along the phase boundaries of rafted membranes has been theorised and indirectly probed by different research groups; however, a direct proof of this phenomenon is still missing to date. We herein exploit atomic force microscopy (AFM) to directly visualise the preferential adsorption of gold nanoparticles (AuNPs) along the phase boundaries of multicomponent SLBs (previously characterised by neutron reflectivity), obtained from synthetic vesicles containing both an Ld and an Lo phase. The quantitative localisation and morphometry of AuNPs adsorbed on the SLB reveal important information on their interaction with the lipid matrix and directly prove the already theorised differential NPs-lipid interaction at the phase boundaries. The presented results could help the development of future NP-based applications, involving NPs adsorption on membranes with nanoscale phase segregations.
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Affiliation(s)
- Andrea Ridolfi
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Florence, Italy.,Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), Bologna, Italy.,Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Florence, Italy
| | - Lucrezia Caselli
- Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Florence, Italy
| | - Costanza Montis
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Florence, Italy.,Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Florence, Italy
| | - Gaetano Mangiapia
- GEMS am Heinz Maier-Leibnitz Zentrum (MLZ), Helmholtz-Zentrum Geesthacht GmbH, Garching, Germany
| | - Debora Berti
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Florence, Italy.,Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Florence, Italy
| | - Marco Brucale
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Florence, Italy.,Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), Bologna, Italy
| | - Francesco Valle
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Florence, Italy.,Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), Bologna, Italy
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98
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Kamiya N, Kayanuma M, Fujitani H, Shinoda K. A New Lipid Force Field (FUJI). J Chem Theory Comput 2020; 16:3664-3676. [PMID: 32384238 DOI: 10.1021/acs.jctc.9b01195] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
To explore inhomogeneous and anisotropic systems such as lipid bilayers, the Lennard-Jones particle mesh Ewald (LJ-PME) method has been applied without a conventional isotropic dispersion correction. As the popular AMBER and CHARMM lipid force fields were developed using a cutoff scheme, their lipid bilayers unacceptably shrink when using the LJ-PME method. In this study, a new all-atom lipid force field (FUJI) was developed on the basis of the AMBER force-field scheme including the Lipid14 van der Waals parameters. Point charges were calculated using the restrained electrostatic potentials of many lipid conformers. Further, torsion energy profiles were calculated using high-level ab initio molecular orbitals (LCCSD(T)/Aug-cc-pVTZ//LMP2/Aug-cc-pVTZ), following which the molecular mechanical dihedral parameters were derived through a fast Fourier transform. By incorporation of these parameters into a new lipid force field without fitting experimental data, the desired lipid characteristics such as the area per lipid and lateral diffusion coefficients were obtained through GROMACS molecular dynamics simulations using the LJ-PME method and virtual hydrogen sites. The calculated area per lipid and lateral diffusion coefficients showed satisfactory agreement with experimental data. Furthermore, the electron-density profiles along the membrane normal were calculated for pure lipid bilayers, and the resulting membrane thicknesses agreed well with the experimental values. As the new lipid force field is compatible with FUJI for protein and small molecules, the new FUJI force field will offer accurate modeling for complex systems consisting of various membrane proteins and lipids.
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Affiliation(s)
- Nozomu Kamiya
- Fujitsu Limited Bio-IT R&D Office, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Megumi Kayanuma
- Research Center for Computational Design of Advanced Functional Materials, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - Hideaki Fujitani
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Keiko Shinoda
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
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99
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Mostofian B, Johnson QR, Smith JC, Cheng X. Carotenoids promote lateral packing and condensation of lipid membranes. Phys Chem Chem Phys 2020; 22:12281-12293. [PMID: 32432296 DOI: 10.1039/d0cp01031f] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Carotenoids are pigment molecules that protect biomembranes against degradation and may be involved in the formation of functional bacterial membrane microdomains. Little is known on whether different types of carotenoids have different effects on the membrane or if there is any concentration dependence of these effects. In this work, we present results from molecular dynamics simulations of phospholipid bilayers containing different amounts of either β-carotene or zeaxanthin. Both β-carotene and zeaxanthin show the ability to laterally condense the membrane lipids and reduce their inter-leaflet interactions. With increasing concentrations, both carotenoids increase the bilayer thickness and rigidity. The results reveal that carotenoids have similar effects to cholesterol on regulating the behavior of fluid-phase membranes, suggesting that they could function as sterol substitutes and confirming their potential role in the formation of functional membrane domains.
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Affiliation(s)
- Barmak Mostofian
- Center for Molecular Biophysics, Oak Ridge National Lab, Oak Ridge, TN 37830, USA.
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100
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Bore SL, Kolli HB, De Nicola A, Byshkin M, Kawakatsu T, Milano G, Cascella M. Hybrid particle-field molecular dynamics under constant pressure. J Chem Phys 2020; 152:184908. [PMID: 32414244 DOI: 10.1063/5.0007445] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Hybrid particle-field methods are computationally efficient approaches for modeling soft matter systems. So far, applications of these methodologies have been limited to constant volume conditions. Here, we reformulate particle-field interactions to represent systems coupled to constant external pressure. First, we show that the commonly used particle-field energy functional can be modified to model and parameterize the isotropic contributions to the pressure tensor without interfering with the microscopic forces on the particles. Second, we employ a square gradient particle-field interaction term to model non-isotropic contributions to the pressure tensor, such as in surface tension phenomena. This formulation is implemented within the hybrid particle-field molecular dynamics approach and is tested on a series of model systems. Simulations of a homogeneous water box demonstrate that it is possible to parameterize the equation of state to reproduce any target density for a given external pressure. Moreover, the same parameterization is transferable to systems of similar coarse-grained mapping resolution. Finally, we evaluate the feasibility of the proposed approach on coarse-grained models of phospholipids, finding that the term between water and the lipid hydrocarbon tails is alone sufficient to reproduce the experimental area per lipid in constant-pressure simulations and to produce a qualitatively correct lateral pressure profile.
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Affiliation(s)
- Sigbjørn Løland Bore
- Department of Chemistry, and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
| | - Hima Bindu Kolli
- Department of Chemistry, and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
| | - Antonio De Nicola
- Department of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata-ken 992-8510, Japan
| | - Maksym Byshkin
- Institute of Computational Science, Università Della Svizzera Italiana, 6900 Lugano, Switzerland
| | - Toshihiro Kawakatsu
- Department of Physics, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Giuseppe Milano
- Department of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata-ken 992-8510, Japan
| | - Michele Cascella
- Department of Chemistry, and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
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