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Shamaprasad P, Nădăban A, Iacovella CR, Gooris GS, Bunge AL, Bouwstra JA, McCabe C. The phase behavior of skin-barrier lipids: A combined approach of experiments and simulations. Biophys J 2024:S0006-3495(24)00477-6. [PMID: 39030908 DOI: 10.1016/j.bpj.2024.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 04/28/2024] [Accepted: 07/15/2024] [Indexed: 07/22/2024] Open
Abstract
Skin barrier function is localized in its outermost layer, the stratum corneum (SC), which is comprised of corneocyte cells embedded in an extracellular lipid matrix containing ceramides (CERs), cholesterol (CHOL), and free fatty acids (FFAs). The unique structure and composition of this lipid matrix are important for skin barrier function. In this study, experiments and molecular dynamics simulation were combined to investigate the structural properties and phase behavior of mixtures containing nonhydroxy sphingosine CER (CER NS), CHOL, and FFA. X-ray scattering for mixtures with varying CHOL levels revealed the presence of the 5.4 nm short periodicity phase in the presence of CHOL. Bilayers in coarse-grained multilayer simulations of the same compositions contained domains with thicknesses of approximately 5.3 and 5.8 nm that are associated with elevated levels, respectively, of CER sphingosine chains with CHOL, and CER acyl chains with FFA chains. The prevalence of the thicker domain increased with decreasing CHOL content. This might correspond to a phase with ∼5.8 nm spacing observed by x-rays (other details unknown) in mixtures with lower CHOL content. Scissoring and stretching frequencies from Fourier transform infrared spectroscopy (FTIR) also indicate interaction between FFA and CER acyl chains and little interaction between CER acyl and CER sphingosine chains, which requires CER molecules to adopt a predominantly extended conformation. In the simulated systems, neighbor preferences of extended CER chains align more closely with the FTIR observations than those of CERs with hairpin ceramide chains. Both FTIR and atomistic simulations of reverse mapped multilayer membranes detect a hexagonal to fluid phase transition between 65 and 80°C. These results demonstrate the utility of a collaborative experimental and simulation effort in gaining a more comprehensive understanding of SC lipid membranes.
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Affiliation(s)
- Parashara Shamaprasad
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee
| | - Andreea Nădăban
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands
| | - Christopher R Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee
| | - Gerrit S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands
| | - Annette L Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee; School of Engineering and Physical Science, Heriot-Watt University, Edinburgh, United Kingdom.
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2
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Nădăban A, Frame CO, El Yachioui D, Gooris GS, Dalgliesh RM, Malfois M, Iacovella CR, Bunge AL, McCabe C, Bouwstra JA. The Sphingosine and Phytosphingosine Ceramide Ratio in Lipid Models Forming the Short Periodicity Phase: An Experimental and Molecular Simulation Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:13794-13809. [PMID: 38917358 PMCID: PMC11238587 DOI: 10.1021/acs.langmuir.4c00554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/27/2024]
Abstract
The lipids located in the outermost layer of the skin, the stratum corneum (SC), play a crucial role in maintaining the skin barrier function. The primary components of the SC lipid matrix are ceramides (CERs), cholesterol (CHOL), and free fatty acids (FFAs). They form two crystalline lamellar phases: the long periodicity phase (LPP) and the short periodicity phase (SPP). In inflammatory skin conditions like atopic dermatitis and psoriasis, there are changes in the SC CER composition, such as an increased concentration of a sphingosine-based CER (CER NS) and a reduced concentration of a phytosphingosine-based CER (CER NP). In the present study, a lipid model was created exclusively forming the SPP, to examine whether alterations in the CER NS:CER NP molar ratio would affect the lipid organization. Experimental data were combined with molecular dynamics simulations of lipid models containing CER NS:CER NP at ratios of 1:2 (mimicking a healthy SC ratio) and 2:1 (observed in inflammatory skin diseases), mixed with CHOL and lignoceric acid as the FFA. The experimental findings show that the acyl chains of CER NS and CER NP and the FFA are in close proximity within the SPP unit cell, indicating that CER NS and CER NP adopt a linear conformation, similarly as observed for the LPP. Both the experiments and simulations indicate that the lamellar organization is the same for the two CER NS:CER NP ratios while the SPP NS:NP 1:2 model had a slightly denser hydrogen bonding network than the SPP NS:NP 2:1 model. The simulations show that this might be attributed to intermolecular hydrogen bonding with the additional hydroxide group on the headgroup of CER NP compared with CER NS.
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Affiliation(s)
- Andreea Nădăban
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
| | - Chloe O Frame
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States of America
| | - Dounia El Yachioui
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
| | - Gerrit S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
| | - Robert M Dalgliesh
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Marc Malfois
- ALBA Synchrotron, Cerdanyola del Vallès, 08290 Barcelona, Spain
| | - Christopher R Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States of America
| | - Annette L Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States of America
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States of America
- School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
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Wang Y, Mou X, Ji Y, Pan F, Li S. Interaction of Macromolecular Chain with Phospholipid Membranes in Solutions: A Dissipative Particle Dynamics Simulation Study. Molecules 2023; 28:5790. [PMID: 37570760 PMCID: PMC10420874 DOI: 10.3390/molecules28155790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/24/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023] Open
Abstract
The interaction between macromolecular chains and phospholipid membranes in aqueous solution was investigated using dissipative particle dynamics simulations. Two cases were considered, one in which the macromolecular chains were pulled along parallel to the membrane surfaces and another in which they were pulled vertical to the membrane surfaces. Several parameters, including the radius of gyration, shape factor, particle number, and order parameter, were used to investigate the interaction mechanisms during the dynamics processes by adjusting the pulling force strength of the chains. In both cases, the results showed that the macromolecular chains undergo conformational transitions from a coiled to a rod-like structure. Furthermore, the simulations revealed that the membranes can be damaged and repaired during the dynamic processes. The role of the pulling forces and the adsorption interactions between the chains and membranes differed in the parallel and perpendicular pulling cases. These findings contribute to our understanding of the interaction mechanisms between macromolecules and membranes, and they may have potential applications in biology and medicine.
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Affiliation(s)
- Yuane Wang
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (Y.W.); (X.M.); (Y.J.)
| | - Xuankang Mou
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (Y.W.); (X.M.); (Y.J.)
| | - Yongyun Ji
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (Y.W.); (X.M.); (Y.J.)
| | - Fan Pan
- School of Data Science and Artificial Intelligence, Wenzhou University of Technology, Wenzhou 325035, China
| | - Shiben Li
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (Y.W.); (X.M.); (Y.J.)
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Pan F, Sun L, Li S. Dynamic Processes and Mechanical Properties of Lipid-Nanoparticle Mixtures. Polymers (Basel) 2023; 15:polym15081828. [PMID: 37111975 PMCID: PMC10144953 DOI: 10.3390/polym15081828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/23/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
In this study, we investigate the dynamic processes and mechanical properties of lipid nanoparticle mixtures in a melt via dissipation particle dynamic simulation. By investigating the distribution of nanoparticles in lamellar and hexagonal lipid matrices in equilibrium state and dynamic processes, we observe that the morphology of such composites depends not only on the geometric features of the lipid matrix but also on the concentration of nanoparticles. The dynamic processes are also demonstrated by calculating the average radius of gyration, which indicates the isotropic conformation of lipid molecules in the x-y plane and that the lipid chains are stretched in the z direction with the addition of nanoparticles. Meanwhile, we predict the mechanical properties of lipid-nanoparticle mixtures in lamellar structures by analyzing the interfacial tensions. Results show that the interfacial tension decreased with the increase in nanoparticle concentration. These results provide molecular-level information for the rational and a priori design of new lipid nanocomposites with ad hoc tailored properties.
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Affiliation(s)
- Fan Pan
- School of Data Science and Artificial Intelligence, Wenzhou University of Technology, Wenzhou 325035, China
| | - Lingling Sun
- Department of Physics, Wenzhou University, Wenzhou 325035, China
| | - Shiben Li
- Department of Physics, Wenzhou University, Wenzhou 325035, China
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Shamaprasad P, Frame CO, Moore TC, Yang A, Iacovella CR, Bouwstra JA, Bunge AL, McCabe C. Using molecular simulation to understand the skin barrier. Prog Lipid Res 2022; 88:101184. [PMID: 35988796 PMCID: PMC10116345 DOI: 10.1016/j.plipres.2022.101184] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/15/2022]
Abstract
Skin's effectiveness as a barrier to permeation of water and other chemicals rests almost entirely in the outermost layer of the epidermis, the stratum corneum (SC), which consists of layers of corneocytes surrounded by highly organized lipid lamellae. As the only continuous path through the SC, transdermal permeation necessarily involves diffusion through these lipid layers. The role of the SC as a protective barrier is supported by its exceptional lipid composition consisting of ceramides (CERs), cholesterol (CHOL), and free fatty acids (FFAs) and the complete absence of phospholipids, which are present in most biological membranes. Molecular simulation, which provides molecular level detail of lipid configurations that can be connected with barrier function, has become a popular tool for studying SC lipid systems. We review this ever-increasing body of literature with the goals of (1) enabling the experimental skin community to understand, interpret and use the information generated from the simulations, (2) providing simulation experts with a solid background in the chemistry of SC lipids including the composition, structure and organization, and barrier function, and (3) presenting a state of the art picture of the field of SC lipid simulations, highlighting the difficulties and best practices for studying these systems, to encourage the generation of robust reproducible studies in the future. This review describes molecular simulation methodology and then critically examines results derived from simulations using atomistic and then coarse-grained models.
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Affiliation(s)
- Parashara Shamaprasad
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Chloe O Frame
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Timothy C Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Alexander Yang
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Christopher R Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Joke A Bouwstra
- Division of BioTherapeutics, LACDR, Leiden University, 2333 CC Leiden, the Netherlands
| | - Annette L Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO 80401, United States of America
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America; School of Engineering and Physical Science, Heriot-Watt University, Edinburgh, United Kingdom.
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Shamaprasad P, Moore TC, Xia D, Iacovella CR, Bunge AL, McCabe C. Multiscale Simulation of Ternary Stratum Corneum Lipid Mixtures: Effects of Cholesterol Composition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:7496-7511. [PMID: 35671175 PMCID: PMC9309713 DOI: 10.1021/acs.langmuir.2c00471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Molecular dynamics simulations of mixtures of the ceramide nonhydroxy-sphingosine (NS), cholesterol, and a free fatty acid are performed to gain molecular-level understanding of the structure of the lipids found in the stratum corneum layer of skin. A new coarse-grained force field for cholesterol was developed using the multistate iterative Boltzmann inversion (MS-IBI) method. The coarse-grained cholesterol force field is compatible with previously developed coarse-grained force fields for ceramide NS, free fatty acids, and water and validated against atomistic simulations of these lipids using the CHARMM force field. Self-assembly simulations of multilayer structures using these coarse-grained force fields are performed, revealing that a large fraction of the ceramides adopt extended conformations, which cannot occur in the single bilayer in water structures typically studied using molecular simulation. Cholesterol fluidizes the membrane by promoting packing defects, and an increase in cholesterol content is found to reduce the bilayer thickness due to an increase in interdigitation of the C24 lipid tails, consistent with experimental observations. Using a reverse-mapping procedure, a self-assembled coarse-grained multilayer system is used to construct an equivalent structure with atomistic resolution. Simulations of this atomistic structure are found to closely agree with experimentally derived neutron scattering length density profiles. Significant interlayer hydrogen bonding is observed in the inner layers of the atomistic multilayer structure that are not found in the outer layers in contact with water or in equivalent bilayer structures. This work highlights the importance of simulating multilayer structures, as compared to the more commonly studied bilayer systems, to enable more appropriate comparisons with multilayer experimental membranes. These results also provide validation of the efficacy of the MS-IBI derived coarse-grained force fields and the framework for multiscale simulation.
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Affiliation(s)
- Parashara Shamaprasad
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Timothy C. Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Donna Xia
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Christopher R. Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Annette L. Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO, USA, 80401
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA, 37235-1604
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Chen Y, Wang Z, Ji Y, He L, Wang X, Li S. Asymmetric Lipid Membranes under Shear Flows: A Dissipative Particle Dynamics Study. MEMBRANES 2021; 11:655. [PMID: 34564472 PMCID: PMC8465239 DOI: 10.3390/membranes11090655] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/12/2021] [Accepted: 08/20/2021] [Indexed: 12/03/2022]
Abstract
We investigate the phase behavior of the asymmetric lipid membranes under shear flows, using the dissipative particle dynamics simulation. Two cases, the weak and strong shear flows, are considered for the asymmetric lipid microstructures. Three typical asymmetric structures, the membranes, tubes, and vesicle, are included in the phase diagrams, where the effect of two different types of lipid chain length on the formation of asymmetric membranes is evaluated. The dynamic processes are demonstrated for the asymmetric membranes by calculating the average radius of gyration and shape factor. The result indicates that different shear flows will affect the shape of the second type of lipid molecules; the shape of the first type of lipid molecules is more stable than that of the second type of lipid molecules. The mechanical properties are investigated for the asymmetric membranes by analyzing the interface tension. The results reveal an absolute pressure at the junctions of different types of particles under the weak shear flow; the other positions are almost in a state of no pressure; there is almost no pressure inside the asymmetric lipid membrane structure under the strong shear flow. The findings will help us to understand the potential applications of asymmetric lipid microstructures in the biological and medical fields.
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Affiliation(s)
| | | | | | | | | | - Shiben Li
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (Y.C.); (Z.W.); (Y.J.); (L.H.); (X.W.)
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8
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Dai X, Ji Y, Wang Z, He L, Wang X, Li S. Interaction between Bottlebrush Polymers and Phospholipid Membranes in Solutions. Polymers (Basel) 2020; 12:E3033. [PMID: 33348889 PMCID: PMC7766109 DOI: 10.3390/polym12123033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 11/23/2022] Open
Abstract
In this work, the interactions between bottlebrush polymers and phospholipid membranes were investigated using dissipative particle dynamics simulations. The weak and strong adsorption phenomena between the polymers and membranes were examined by calculating the system parameters. A spring model was introduced to explain the variances in the shape factors and the radius of gyration of the bottlebrush polymers, as well as the order parameters of the phospholipid membrane in the pulling processes. This work provides further understanding for the application of bottlebrush polymers in biological processes.
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Affiliation(s)
| | | | - Zhenguo Wang
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (X.D.); (Y.J.); (L.H.); (X.W.)
| | | | | | - Shiben Li
- Department of Physics, Wenzhou University, Wenzhou 325035, China; (X.D.); (Y.J.); (L.H.); (X.W.)
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9
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Shan Y, Ji Y, Wang X, He L, Li S. Predicting asymmetric phospholipid microstructures in solutions. RSC Adv 2020; 10:24521-24532. [PMID: 35516199 PMCID: PMC9055179 DOI: 10.1039/d0ra03732j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 06/18/2020] [Indexed: 01/29/2023] Open
Abstract
Asymmetric phospholipid microstructures, such as asymmetric phospholipid membranes, have potential applications in biological and medicinal processes. Here, we used the dissipative particle dynamics simulation method to predict the asymmetric phospholipid microstructures in aqueous solutions. The asymmetric phospholipid membranes, tubes and vesicles are determined and characterized by the chain density distributions and order parameters. The phase diagrams are constructed to evaluate the effects of the chain length on the asymmetric structure formations at equilibrium states, while the average radius of gyration and shape factors are calculated to analyze the asymmetric structure formations in the non-equilibrium processes. Meanwhile, we predicted the mechanical properties of the asymmetric membranes by analyzing the spatial distributions of the interface tensions and osmotic pressures in solutions.
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Affiliation(s)
- Yue Shan
- Department of Physics, Wenzhou University Wenzhou Zhejiang 325035 China
| | - Yongyun Ji
- Department of Physics, Wenzhou University Wenzhou Zhejiang 325035 China
| | - Xianghong Wang
- Department of Physics, Wenzhou University Wenzhou Zhejiang 325035 China
| | - Linli He
- Department of Physics, Wenzhou University Wenzhou Zhejiang 325035 China
| | - Shiben Li
- Department of Physics, Wenzhou University Wenzhou Zhejiang 325035 China
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Yang C, Dai X, Yang S, Ma L, Chen L, Gao R, Wu X, Shi X. Coarse-grained molecular dynamics simulations of the effect of edge activators on the skin permeation behavior of transfersomes. Colloids Surf B Biointerfaces 2019; 183:110462. [PMID: 31479973 DOI: 10.1016/j.colsurfb.2019.110462] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 08/20/2019] [Accepted: 08/25/2019] [Indexed: 11/30/2022]
Abstract
Transfersomes (TRS) can provide sustained drug delivery and themselves are biocompatible, biodegradable and nontoxic. Edge activators (EAs) are key factors for increasing the deformability of TRS, and this active deformation mechanism is of commercial interest, especially at the molecular level. Accordingly, in this paper, the deformability of pure dipalmitoyl phosphatidylcholine (DPPC) vesicles, TRS with sodium cholate as an EA, and DPPC vesicles containing pogostone (POG) were compared via umbrella sampling technology. The DPPC conformation and membrane fluidity of these three types of bilayer systems were evaluated, and the changes in the membrane properties of vesicles caused by EAs were studied. EAs could increase the deformability of TRS by decreasing the deformation energy barrier due to their amphiphilic structures, which was similar to those of DPPC molecules. The membrane properties also changed via treatment with EAs including altering the tail chain angle, disturbing the ordered tail chain arrangement and prompting lateral diffusion of DPPC molecules. In addition, the impact of EAs on DPPC bilayers was further demonstrated to be concentration dependent. An ideal concentration was identified for the lowest amount of EA that offered a gel-liquid-crystalline phase transition of DPPC bilayers. Importantly, POG, a lipophobic transdermal drug, can also affect the skin permeation behavior of vesicles but had weaker effects than EA.
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Affiliation(s)
- Chang Yang
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
| | - Xingxing Dai
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory of TCM-Information Engineer of State Administration of TCM, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
| | - Shufang Yang
- Sinopharm Zhijun (Shenzhen) Pharmaceutical Co., Ltd., No. 16 of Lanqing 1stRoad, Guanlan Hi-tech Industrial Park, Longhua District, Shenzhen, 518109, China.
| | - Lina Ma
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory of TCM-Information Engineer of State Administration of TCM, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
| | - Liping Chen
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
| | - Ruilin Gao
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
| | - Xiaowen Wu
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
| | - Xinyuan Shi
- Beijing University of Chinese Medicine, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory of TCM-Information Engineer of State Administration of TCM, No. 11 of North 3rd Ring East Road, Chaoyang District, Beijing, 100029, China; Key Laboratory for Production Process Control and Quality Evaluation of Traditional Chinese Medicine, Beijing Municipal Science & Technology Commission, Beijing, 100029, China.
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11
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Podewitz M, Wang Y, Gkeka P, von Grafenstein S, Liedl KR, Cournia Z. Phase Diagram of a Stratum Corneum Lipid Mixture. J Phys Chem B 2018; 122:10505-10521. [DOI: 10.1021/acs.jpcb.8b07200] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Maren Podewitz
- Institute of General, Inorganic and Theoretical Chemistry, and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Yin Wang
- Institute of General, Inorganic and Theoretical Chemistry, and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Paraskevi Gkeka
- Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou, 11527 Athens, Greece
| | - Susanne von Grafenstein
- Institute of General, Inorganic and Theoretical Chemistry, and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Klaus R. Liedl
- Institute of General, Inorganic and Theoretical Chemistry, and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Zoe Cournia
- Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou, 11527 Athens, Greece
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12
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Parameterization of a coarse-grained model of cholesterol with point-dipole electrostatics. J Comput Aided Mol Des 2018; 32:1259-1271. [DOI: 10.1007/s10822-018-0164-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 09/12/2018] [Indexed: 12/14/2022]
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13
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Del Regno A, Notman R. Permeation pathways through lateral domains in model membranes of skin lipids. Phys Chem Chem Phys 2018; 20:2162-2174. [DOI: 10.1039/c7cp03258g] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Lateral organisation of skin lipids in membranes produces regions with different permeability; water permeation is favoured through cholesterol-rich regions.
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Affiliation(s)
| | - Rebecca Notman
- Department of Chemistry, University of Warwick
- Coventry
- UK
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14
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Wang S, Bresme F. Simulation Studies on the Lipid Interaction and Conformation of Novel Drug-Delivery Pseudopeptidic Polymers. J Phys Chem B 2017; 121:9113-9125. [PMID: 28870066 DOI: 10.1021/acs.jpcb.7b06562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pseudopeptides based on poly(l-lysine isophthalamide) backbone have emerged as promising drug delivery candidates due to their pH-activated membrane disruption ability. To gain molecular understanding on these novel polymeric species, we have constructed force-field parameters and simulated the behaviors of polymers with and without phenylalanine grafted as side chains under conditions compatible with different pHs. The free energy changes upon polymer permeation through membrane were calculated using the umbrella sampling technique. We show that both polymers with and without grafts interact better with the membrane under conditions compatible with lower pH. The conformational states of the polymers were investigated in water and at a water-membrane interface. On the basis of Markov state modeling results, we propose a possible advantage of the grafted polymer over the ungrafted polymer for membrane rupture because of its quicker conformational rearrangement kinetics.
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Affiliation(s)
- Shuzhe Wang
- Department of Chemistry, Imperial College London , SW7 2AZ London, U.K
| | - Fernando Bresme
- Department of Chemistry, Imperial College London , SW7 2AZ London, U.K
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15
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Qiang X, Wang X, Ji Y, Li S, He L. Liquid-crystal self-assembly of lipid membranes on solutions: A dissipative particle dynamic simulation study. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.03.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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16
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Moore TC, Iacovella CR, Hartkamp R, Bunge AL, McCabe C. A Coarse-Grained Model of Stratum Corneum Lipids: Free Fatty Acids and Ceramide NS. J Phys Chem B 2016; 120:9944-58. [PMID: 27564869 PMCID: PMC5287476 DOI: 10.1021/acs.jpcb.6b08046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Ceramide (CER)-based biological membranes are used both experimentally and in simulations as simplified model systems of the skin barrier. Molecular dynamics studies have generally focused on simulating preassembled structures using atomistically detailed models of CERs, which limit the system sizes and time scales that can practically be probed, rendering them ineffective for studying particular phenomena, including self-assembly into bilayer and lamellar superstructures. Here, we report on the development of a coarse-grained (CG) model for CER NS, the most abundant CER in human stratum corneum. Multistate iterative Boltzmann inversion is used to derive the intermolecular pair potentials, resulting in a force field that is applicable over a range of state points and suitable for studying ceramide self-assembly. The chosen CG mapping, which includes explicit interaction sites for hydroxyl groups, captures the directional nature of hydrogen bonding and allows for accurate predictions of several key structural properties of CER NS bilayers. Simulated wetting experiments allow the hydrophobicity of CG beads to be accurately tuned to match atomistic wetting behavior, which affects the whole system, since inaccurate hydrophobic character is found to unphysically alter the lipid packing in hydrated lamellar states. We find that CER NS can self-assemble into multilamellar structures, enabling the study of lipid systems more representative of the multilamellar lipid structures present in the skin barrier. The coarse-grained force field derived herein represents an important step in using molecular dynamics to study the human skin barrier, which gives a resolution not available through experiment alone.
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Affiliation(s)
- Timothy C. Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
| | - Christopher R. Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
| | - Remco Hartkamp
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
| | - Annette L. Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO 80401
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235
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17
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Lyubartsev AP, Rabinovich AL. Force Field Development for Lipid Membrane Simulations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2483-2497. [PMID: 26766518 DOI: 10.1016/j.bbamem.2015.12.033] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 12/21/2015] [Accepted: 12/23/2015] [Indexed: 02/04/2023]
Abstract
With the rapid development of computer power and wide availability of modelling software computer simulations of realistic models of lipid membranes, including their interactions with various molecular species, polypeptides and membrane proteins have become feasible for many research groups. The crucial issue of the reliability of such simulations is the quality of the force field, and many efforts, especially in the latest several years, have been devoted to parametrization and optimization of the force fields for biomembrane modelling. In this review, we give account of the recent development in this area, covering different classes of force fields, principles of the force field parametrization, comparison of the force fields, and their experimental validation. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg.
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Affiliation(s)
- Alexander P Lyubartsev
- Department of Materials and Environmental Chemistry, Stockholm University, SE 106 91, Stockholm, Sweden.
| | - Alexander L Rabinovich
- Institute of Biology, Karelian Research Center, Russian Academy of Sciences, Pushkinskaya 11, Petrozavodsk, 185910, Russian Federation.
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18
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Paloncýová M, Vávrová K, Sovová Ž, DeVane R, Otyepka M, Berka K. Structural Changes in Ceramide Bilayers Rationalize Increased Permeation through Stratum Corneum Models with Shorter Acyl Tails. J Phys Chem B 2015; 119:9811-9. [DOI: 10.1021/acs.jpcb.5b05522] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Markéta Paloncýová
- Regional
Centre of Advanced Technologies and Materials, Department of Physical
Chemistry, Faculty of Science, Palacký University Olomouc, tř.
17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Kateřina Vávrová
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Žofie Sovová
- Regional
Centre of Advanced Technologies and Materials, Department of Physical
Chemistry, Faculty of Science, Palacký University Olomouc, tř.
17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Russell DeVane
- Corporate Modeling & Simulation, Procter & Gamble, 8611 Beckett Road, West Chester, Ohio 45069, United States
| | - Michal Otyepka
- Regional
Centre of Advanced Technologies and Materials, Department of Physical
Chemistry, Faculty of Science, Palacký University Olomouc, tř.
17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Karel Berka
- Regional
Centre of Advanced Technologies and Materials, Department of Physical
Chemistry, Faculty of Science, Palacký University Olomouc, tř.
17. listopadu 12, 771 46 Olomouc, Czech Republic
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19
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Róg T, Vattulainen I. Cholesterol, sphingolipids, and glycolipids: what do we know about their role in raft-like membranes? Chem Phys Lipids 2014; 184:82-104. [PMID: 25444976 DOI: 10.1016/j.chemphyslip.2014.10.004] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Revised: 10/24/2014] [Accepted: 10/25/2014] [Indexed: 12/14/2022]
Abstract
Lipids rafts are considered to be functional nanoscale membrane domains enriched in cholesterol and sphingolipids, characteristic in particular of the external leaflet of cell membranes. Lipids, together with membrane-associated proteins, are therefore considered to form nanoscale units with potential specific functions. Although the understanding of the structure of rafts in living cells is quite limited, the possible functions of rafts are widely discussed in the literature, highlighting their importance in cellular functions. In this review, we discuss the understanding of rafts that has emerged based on recent atomistic and coarse-grained molecular dynamics simulation studies on the key lipid raft components, which include cholesterol, sphingolipids, glycolipids, and the proteins interacting with these classes of lipids. The simulation results are compared to experiments when possible.
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Affiliation(s)
- Tomasz Róg
- Department of Physics, Tampere University of Technology, Tampere, Finland
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology, Tampere, Finland; MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark.
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20
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Moore TC, Iacovella CR, McCabe C. Derivation of coarse-grained potentials via multistate iterative Boltzmann inversion. J Chem Phys 2014; 140:224104. [PMID: 24929371 PMCID: PMC4187284 DOI: 10.1063/1.4880555] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 05/19/2014] [Indexed: 11/15/2022] Open
Abstract
In this work, an extension is proposed to the standard iterative Boltzmann inversion (IBI) method used to derive coarse-grained potentials. It is shown that the inclusion of target data from multiple states yields a less state-dependent potential, and is thus better suited to simulate systems over a range of thermodynamic states than the standard IBI method. The inclusion of target data from multiple states forces the algorithm to sample regions of potential phase space that match the radial distribution function at multiple state points, thus producing a derived potential that is more representative of the underlying interactions. It is shown that the algorithm is able to converge to the true potential for a system where the underlying potential is known. It is also shown that potentials derived via the proposed method better predict the behavior of n-alkane chains than those derived via the standard IBI method. Additionally, through the examination of alkane monolayers, it is shown that the relative weight given to each state in the fitting procedure can impact bulk system properties, allowing the potentials to be further tuned in order to match the properties of reference atomistic and/or experimental systems.
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Affiliation(s)
- Timothy C Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235, USA
| | - Christopher R Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235, USA
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235, USA
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21
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Pomorski TG, Nylander T, Cárdenas M. Model cell membranes: discerning lipid and protein contributions in shaping the cell. Adv Colloid Interface Sci 2014; 205:207-20. [PMID: 24268587 DOI: 10.1016/j.cis.2013.10.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 10/24/2013] [Accepted: 10/24/2013] [Indexed: 01/01/2023]
Abstract
The high complexity of biological membranes has motivated the development and application of a wide range of model membrane systems to study biochemical and biophysical aspects of membranes in situ under well defined conditions. The aim is to provide fundamental understanding of processes controlled by membrane structure, permeability and curvature as well as membrane proteins by using a wide range of biochemical, biophysical and microscopic techniques. This review gives an overview of some currently used model biomembrane systems. We will also discuss some key membrane protein properties that are relevant for protein-membrane interactions in terms of protein structure and how it is affected by membrane composition, phase behavior and curvature.
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Affiliation(s)
- Thomas Günther Pomorski
- Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
| | - Tommy Nylander
- Department of Chemistry, Division of Physical Chemistry, Lund University, Gettingevägen 60, SE-22100 Lund, Sweden
| | - Marité Cárdenas
- Department of Chemistry/Nano-Science Center, University of Copenhagen, DK-2100 Copenhagen, Denmark.
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22
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Cui ZK, Lafleur M. Lamellar self-assemblies of single-chain amphiphiles and sterols and their derived liposomes: distinct compositions and distinct properties. Colloids Surf B Biointerfaces 2013; 114:177-85. [PMID: 24184913 DOI: 10.1016/j.colsurfb.2013.09.042] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 09/16/2013] [Accepted: 09/18/2013] [Indexed: 11/17/2022]
Abstract
Typically, single-chain amphiphiles and sterols do not form fluid lamellar phases once hydrated individually. Most of the single-chain amphiphiles form actually micelles in aqueous environments, while sterols display a very limited solubility in water. However, under certain conditions, mixtures of single-chain amphiphiles and sterols lead to the formation of stable fluid bilayers. Over the past decade, several of these systems leading to fluid lamellar self-assemblies have been identified and this article reviews the current knowledge relative to these non-phospholipid bilayers made of single-chain amphiphiles and sterols. It presents an integrated view about the molecular features that are required for their stability, the properties they share, and the origin of these characteristics. It was also shown that these lamellar systems could lead to the formation of unilamellar vesicles, similar to phospholipid based liposomes. These vesicles display distinct properties that make them potentially appealing for technological applications; they display a limited permeability, they are stable, they are formed with molecules that are relatively chemically inert (and relatively cheap), and they can be readily functionalized. The features of these distinct liposomes and their technological applications are reviewed. Finally, the putative biological implications of these non-phospholipid fluid bilayers are also discussed.
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Affiliation(s)
- Zhong-Kai Cui
- Department of Chemistry, Center for Self-Assembled Chemical Structures (CSACS), Université de Montréal, C.P. 6128, Succ. Centre Ville, Montréal, Québec H3C 3J7, Canada
| | - Michel Lafleur
- Department of Chemistry, Center for Self-Assembled Chemical Structures (CSACS), Université de Montréal, C.P. 6128, Succ. Centre Ville, Montréal, Québec H3C 3J7, Canada.
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23
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Rabinovich AL, Lyubartsev AP. Computer simulation of lipid membranes: Methodology and achievements. POLYMER SCIENCE SERIES C 2013. [DOI: 10.1134/s1811238213070060] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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24
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Abstract
Coarse-grained (CG) models have proven to be very effective tools in the study of phenomena or systems that involve large time- and length-scales. By decreasing the degrees of freedom in the system and using softer interactions than seen in atomistic models, larger timesteps can be used and much longer simulation times can be studied. CG simulations are widely used to study systems of biological importance that are beyond the reach of atomistic simulation, necessitating a computationally efficient and accurate CG model for water. In this review, we discuss the methods used for developing CG water models and the relative advantages and disadvantages of the resulting models. In general, CG water models differ with regards to how many waters each CG group or bead represents, whether analytical or tabular potentials have been used to describe the interactions, and how the model incorporates electrostatic interactions. Finally, how the models are parameterized depends on their application, so, while some are fitted to experimental properties such as surface tension and density, others are fitted to radial distribution functions extracted from atomistic simulations.
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Affiliation(s)
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville TN 37235-1604
- Department of Chemistry, Vanderbilt University, Nashville TN 37235-1604
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