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Jaikishan S, Lavainne M, Ravald HK, Scobbie K, Dusa F, Maheswari R, Turpeinen J, Eikemans I, Chen R, Rantala J, Aseyev V, Maier NN, Wiedmer SK. Fragment-based approach to study fungicide-biomimetic membrane interactions. SOFT MATTER 2024. [PMID: 39012330 DOI: 10.1039/d4sm00648h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
In this study, the molecular interactions of the allylamine-type fungicide butenafine and a set of substructures ("fragments") with liposomes mimicking biological membranes were studied to gain a better understanding of the structural factors governing membrane affinity and perturbation. Specifically, drug/fragment-membrane interactions were investigated using an interdisciplinary approach involving micro differential scanning calorimetry, open-tubular capillary electrochromatography, nanoplasmonic sensing, and quartz crystal microbalance. By incubating the drug and the fragment compounds with liposomes with varying lipid composition or by externally adding the compounds to preformed liposomes, a detailed mechanistic picture on the underlying drug/fragment-membrane interactions was obtained. The nature and the degree of ionisation of polar head groups of the lipids had a major influence on the nature of drug-membrane interactions, and so had the presence and relative concentration of cholesterol within the membranes. The in-depth understanding of drug/fragment-membranes interactions established by the presented interdisciplinary fragment-based approach may be useful in guiding the design and early-stage evaluation of prospective antifungal drug candidates, and the discovery of agents with improved membrane penetrating characteristics in general.
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Affiliation(s)
- Shishir Jaikishan
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Marine Lavainne
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Henri K Ravald
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Kieran Scobbie
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Filip Dusa
- Institute of Analytical Chemistry, Czech Academy of Sciences, Veveří 97, Brno 60200, Czech Republic
| | - Rekha Maheswari
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Jenni Turpeinen
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Ian Eikemans
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Rui Chen
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Julia Rantala
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Vladimir Aseyev
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Norbert N Maier
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
| | - Susanne K Wiedmer
- Department of Chemistry, A.I. Virtasen aukio 1, POB 55, 00014 University of Helsinki, Finland.
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Roux M, Legrand FX, Bil A, Bonnet V, Djedaini-Pilard F. Fragmentation of DMPC Membranes by a Wedge-Shaped Amphiphilic Cyclodextrin into Bicellar-like Aggregates. J Phys Chem B 2023; 127:2475-2487. [PMID: 36913407 DOI: 10.1021/acs.jpcb.2c07331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Abstract
Small bilayer lipid aggregates such as bicelles provide useful isotropic or anisotropic membrane mimetics for structural studies of biological membranes. We have shown previously by deuterium NMR that a wedge-shaped amphiphilic derivative of trimethyl βcyclodextrin anchored in deuterated DMPC-d27 bilayers through a lauryl acyl chain (TrimβMLC) is able to induce magnetic orientation and fragmentation of the multilamellar membranes. The fragmentation process fully detailed in the present paper is observed with 20% cyclodextrin derivative below 37 °C, where pure TrimβMLC self-assembles in water into large giant micellar structures. After deconvolution of a broad composite 2H NMR isotropic component, we propose a model where the DMPC membranes are progressively disrupted by TrimβMLC into small and large micellar aggregates depending whether they are extracted from the outer or inner layers of the liposomes. Below the fluid-to-gel transition of pure DMPC-d27 membranes (Tc = 21.5 °C), the micellar aggregates vanish progressively until complete extinction at 13 °C, with a probable release of pure TrimβMLC micelles leaving lipid bilayers in the gel phase doped with only a small amount of the cyclodextrin derivative. Bilayer fragmentation between Tc and 13 °C was also observed with 10% and 5% of TrimβMLC, with NMR spectra suggesting possible interactions of micellar aggregates with fluid-like lipids of the Pβ' ripple phase. No membrane orientation and fragmentation was detected with unsaturated POPC membranes, which are able to accommodate the insertion of TrimβMLC without important perturbation. The data are discussed in relation to the formation of possible DMPC bicellar aggregates such as those known to occur after insertion of dihexanoylphosphatidylcholine (DHPC). These bicelles are in particular associated with similar deuterium NMR spectra exhibiting identical composite isotropic components which were never characterized before.
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Affiliation(s)
- Michel Roux
- Université Paris-Saclay, Institute for Integrative Biology of the Cell, URA CNRS 9198, F-91191 Gif sur Yvette CEDEX, France
| | | | - Abed Bil
- Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources, (CNRS UMR 7378), Université de Picardie Jules Verne, 33 Rue Saint Leu, F-80039 Amiens, France
| | - Véronique Bonnet
- Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources, (CNRS UMR 7378), Université de Picardie Jules Verne, 33 Rue Saint Leu, F-80039 Amiens, France
| | - Florence Djedaini-Pilard
- Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources, (CNRS UMR 7378), Université de Picardie Jules Verne, 33 Rue Saint Leu, F-80039 Amiens, France
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3
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Soubias O, Sodt AJ, Teague WE, Hines KG, Gawrisch K. Physiological changes in bilayer thickness induced by cholesterol control GPCR rhodopsin function. Biophys J 2023; 122:973-983. [PMID: 36419350 PMCID: PMC10111215 DOI: 10.1016/j.bpj.2022.11.2937] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/15/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
We monitored the effect on function of the G-protein-coupled receptor (GPCR) rhodopsin from small, stepwise changes in bilayer thickness induced by cholesterol. Over a range of phosphatidylcholine bilayers with hydrophobic thickness from ≈21 Å to 38 Å, the metarhodopsin-I (MI)/metarhodopsin-II (MII) equilibrium was monitored with UV-visible spectroscopy while ordering of hydrocarbon chains was probed by 2H-NMR. Addition of cholesterol shifted equilibrium toward MII for bilayers thinner than the average length of hydrophobic transmembrane helices (27 Å) and to MI for thicker bilayers, while small bilayer thickness changes within the range of the protein hydrophobic thickness drastically up- or downregulated MII formation. The cholesterol-induced shifts toward MII for thinner membranes correlated with the cholesterol-induced increase of bilayer hydrophobic thickness measured by NMR, consistent with continuum elastic modeling. The energetic penalty of adding cholesterol to thick bilayers caused rhodopsin oligomerization and a shift toward MI. In membranes of physiological thickness, changes in bilayer mechanical properties induced by cholesterol potentiated the interplay between bilayer and protein thickness resulting in large swings of the MI-MII equilibrium. In membrane containing cholesterol, elastic deformations near the protein are a dominant energetic contribution to the functional equilibrium of the model GPCR rhodopsin.
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Affiliation(s)
- Olivier Soubias
- Macromolecular NMR Section, Center for Structural Biology, Center for Cancer Research, NCI, NIH, Frederick, Maryland.
| | - Alexander J Sodt
- Unit on Membrane Chemical Physics, Eunice Kennedy Shriver NICHD, NIH, Bethesda, Maryland
| | - Walter E Teague
- Section of NMR, Laboratory of Membrane Biochemistry and Biophysics, NIAAA, NIH, Bethesda, Maryland
| | - Kirk G Hines
- Section of NMR, Laboratory of Membrane Biochemistry and Biophysics, NIAAA, NIH, Bethesda, Maryland
| | - Klaus Gawrisch
- Section of NMR, Laboratory of Membrane Biochemistry and Biophysics, NIAAA, NIH, Bethesda, Maryland
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4
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Marcos X, Sixto-López Y, Pérez-Casas S, Correa-Basurto J. Computational study of DMPC liposomes loaded with the N-(2-Hydroxyphenyl)-2-propylpentanamide (HO-AAVPA) and determination of its antiproliferative activity in vitro in NIH-3T3 cells. J Biomol Struct Dyn 2022; 40:11448-11459. [PMID: 34315332 DOI: 10.1080/07391102.2021.1955744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
N-(2-Hydroxyphenyl)-2-propylpentanamide (HO-AAVPA) is a valproic acid (VPA) derivative that has shown promising antiproliferative effects in different cancer cell lines, such as A204, HeLa, and MDA-MB-231. However, its low water solubility could reduce its therapeutic effectiveness. To solve this problem, in this work, we incorporated HO-AAVPA into dimyristoyl-phosphatidylcholine (DMPC) liposomes in the presence or absence of cholesterol (CHOL). Using differential scanning calorimetry (DSC), we found that the transition enthalpy (ΔHtr) of DMPC liposomes is reduced in the presence of CHOL and/or HO-AAVPA, indicating the favorable interactions between CHOL and/or HO-AAVPA and DMPC. Further, by molecular dynamics simulations it was possible to observed that HO-AAVPA migrates from the center of the bilayer toward the water and lipid interface of the DPMC bilayer systems exposing the amine group to water and the aliphatic chain toward the interior of the bilayer. As a consequence, we observed an ordering of the lipid bilayer. Moreover, CHOL harbors into the inner bilayer membrane, increasing the order parameter of the system. The liposomal solutions loaded with HO-AAVPA were tested in the NIH3T3 cell line, showing a reduction in cell proliferation compared to those cells presented without liposomes.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Xelhua Marcos
- Laboratorio de Biofísica y Biocatálisis, Escuela Superior de Medicina, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Yudibeth Sixto-López
- Laboratorio de Diseño y Desarrollo de Nuevos Fármacos e Innovación Biotecnológica (Laboratory for the Design and Development of New Drugs and Biotechnological Innovation) SEPI-ESM Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Silvia Pérez-Casas
- Laboratorio de Biofisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - José Correa-Basurto
- Laboratorio de Diseño y Desarrollo de Nuevos Fármacos e Innovación Biotecnológica (Laboratory for the Design and Development of New Drugs and Biotechnological Innovation) SEPI-ESM Instituto Politécnico Nacional, Ciudad de México, Mexico
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5
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Braithwaite IM, Davis JH. Orientation of Cholesterol in Polyunsaturated Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:15804-15816. [PMID: 36480923 DOI: 10.1021/acs.langmuir.2c02718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The local normal to the fluid liquid crystalline phase of the lipid membrane is an axis of motional symmetry for the molecules that make up the bilayer. The presence of cholesterol in the membrane increases not only the lipid hydrocarbon chain order but also the strength of the membrane's orienting potential. Cholesterol undergoes rapid reorientation about a diffusion axis that is roughly aligned with the long molecular axis, but there is also a slower reorientation of the diffusion axis, or "wobble", relative to the local bilayer normal. The extent of this second, slower motion depends on the degree of order of the lipids that make up the bilayer. We use 2H nuclear magnetic resonance of deuterium-labeled cholesterol to investigate quantitatively the effect of lipid chain unsaturation on cholesterol orientation in a series of phospholipid bilayers. We find that the hydrocarbon chains in membranes composed of polyunsaturated lipids are much more highly disordered than those in membranes composed of saturated lipids but that cholesterol remains aligned roughly along the bilayer normal.
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Affiliation(s)
| | - James H Davis
- Department of Physics, University of Guelph, Guelph, ON, CanadaN1G 2W1
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6
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Szomek M, Reinholdt P, Walther HL, Scheidt HA, Müller P, Obermaier S, Poolman B, Kongsted J, Wüstner D. Natamycin sequesters ergosterol and interferes with substrate transport by the lysine transporter Lyp1 from yeast. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:184012. [PMID: 35914570 DOI: 10.1016/j.bbamem.2022.184012] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/30/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Natamycin is a polyene macrolide, widely employed to treat fungal keratitis and other yeast infections as well as to protect food products against fungal molds. In contrast to other polyene macrolides, such as nystatin or amphotericin B, natamycin does not form pores in yeast membranes, and its mode of action is not well understood. Here, we have employed a variety of spectroscopic methods, computational modeling, and membrane reconstitution to study the molecular interactions of natamycin underlying its antifungal activity. We find that natamycin forms aggregates in an aqueous solution with strongly altered optical properties compared to monomeric natamycin. Interaction of natamycin with model membranes results in a concentration-dependent fluorescence increase which is more pronounced for ergosterol- compared to cholesterol-containing membranes up to 20 mol% sterol. Evidence for formation of specific ergosterol-natamycin complexes in the bilayer is provided. Using nuclear magnetic resonance (NMR) and electron spin resonance (ESR) spectroscopy, we find that natamycin sequesters sterols, thereby interfering with their well-known ability to order acyl chains in lipid bilayers. This effect is more pronounced for membranes containing the sterol of fungi, ergosterol, compared to those containing mammalian cholesterol. Natamycin interferes with ergosterol-dependent transport of lysine by the yeast transporter Lyp1, which we propose to be due to the sequestering of ergosterol, a mechanism that also affects other plasma membrane proteins. Our results provide a mechanistic explanation for the selective antifungal activity of natamycin, which can set the stage for rational design of novel polyenes in the future.
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Affiliation(s)
- Maria Szomek
- Department of Biochemistry and Molecular Biology, PhyLife, Physical Life Sciences, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Peter Reinholdt
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Hanna-Loisa Walther
- Department of Biochemistry and Molecular Biology, PhyLife, Physical Life Sciences, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Holger A Scheidt
- Institute for Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Peter Müller
- Department of Biology, Humboldt University Berlin, Invalidenstr. 43, 10115 Berlin, Germany
| | - Sebastian Obermaier
- Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 Groningen, the Netherlands
| | - Bert Poolman
- Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 Groningen, the Netherlands
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Daniel Wüstner
- Department of Biochemistry and Molecular Biology, PhyLife, Physical Life Sciences, University of Southern Denmark, DK-5230 Odense M, Denmark.
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7
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Doole FT, Kumarage T, Ashkar R, Brown MF. Cholesterol Stiffening of Lipid Membranes. J Membr Biol 2022; 255:385-405. [PMID: 36219221 PMCID: PMC9552730 DOI: 10.1007/s00232-022-00263-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/05/2022] [Indexed: 11/30/2022]
Abstract
Biomembrane order, dynamics, and other essential physicochemical parameters are controlled by cholesterol, a major component of mammalian cell membranes. Although cholesterol is well known to exhibit a condensing effect on fluid lipid membranes, the extent of stiffening that occurs with different degrees of lipid acyl chain unsaturation remains an enigma. In this review, we show that cholesterol locally increases the bending rigidity of both unsaturated and saturated lipid membranes, suggesting there may be a length-scale dependence of the bending modulus. We review our published data that address the origin of the mechanical effects of cholesterol on unsaturated and polyunsaturated lipid membranes and their role in biomembrane functions. Through a combination of solid-state deuterium NMR spectroscopy and neutron spin-echo spectroscopy, we show that changes in molecular packing cause the universal effects of cholesterol on the membrane bending rigidity. Our findings have broad implications for the role of cholesterol in lipid–protein interactions as well as raft-like mixtures, drug delivery applications, and the effects of antimicrobial peptides on lipid membranes.
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Affiliation(s)
- Fathima T Doole
- Deaprtment of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85712, USA
| | - Teshani Kumarage
- Department of Physics, Virginia Tech, Blacksburg, VA, 24061, USA.,Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Rana Ashkar
- Department of Physics, Virginia Tech, Blacksburg, VA, 24061, USA. .,Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA.
| | - Michael F Brown
- Deaprtment of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, 85712, USA. .,Department of Physics, University of Arizona, Tucson, AZ, 85712, USA.
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8
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Nguyen HL, Man VH, Li MS, Derreumaux P, Wang J, Nguyen PH. Elastic moduli of normal and cancer cell membranes revealed by molecular dynamics simulations. Phys Chem Chem Phys 2022; 24:6225-6237. [PMID: 35229839 DOI: 10.1039/d1cp04836h] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Recent studies indicate that there are mechanical differences between normal cells and cancer cells. Because the cell membrane takes part in a variety of vital processes, we test the hypothesis of whether or not two fundamental alterations in the cell membrane, i.e., the overexpression of phosphatidylserine lipids in the outer leaflet and a reduction in cholesterol concentration, could cause the softening in cancer cells. Adopting ten models of normal and cancer cell membranes, we carry out 1 μs all-atom molecular dynamics simulations to compare the structural properties and elasticity properties of two membrane types. We find that the overexpression of the phosphatidylserine lipids in the outer leaflet does not significantly alter the area per lipid, the membrane thickness, the lipid order parameters and the elasticity moduli of the cancer membranes. However, a reduction in the cholesterol concentration leads to clear changes in those quantities, especially decreases in the bending, tilt and twist moduli. This implies that the reduction of cholesterol concentration in the cancer membranes could contribute to the softening of cancer cells.
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Affiliation(s)
- Hoang Linh Nguyen
- Institute for Computational Science and Technology, SBI Building, Quang Trung Software City, Tan Chanh Hiep Ward, District 12, Ho Chi Minh City, Vietnam
| | - Viet Hoang Man
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Mai Suan Li
- Institute for Computational Science and Technology, SBI Building, Quang Trung Software City, Tan Chanh Hiep Ward, District 12, Ho Chi Minh City, Vietnam.,Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
| | - Philippe Derreumaux
- CNRS, Université de Paris, UPR9080, Laboratoire de Biochimie Théorique, Paris, France
| | - Junmei Wang
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Phuong H Nguyen
- CNRS, Université de Paris, UPR9080, Laboratoire de Biochimie Théorique, Paris, France.,Institut de Biologie Physico-Chimique, Fondation Edmond de Rothschild, PSL Research University, Paris, France.
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9
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Kashyap HK. Deciphering Ethanol-Driven Swelling, Rupturing, Aggregation, and Fusion of Lipid Vesicles Using Coarse-Grained Molecular Dynamics Simulations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:2445-2459. [PMID: 35167280 DOI: 10.1021/acs.langmuir.1c02763] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Traditionally, liquid ethanol is known to enhance the permeability of lipid membranes and causes vesicle aggregation and fusion. However, how the amphiphilic ethanol molecules perturb the lipid vesicles to facilitate their aggregation or fusion has not been addressed at any level of molecular simulations. Herein, not only have we developed a coarse-grained (CG) model for liquid ethanol, its aqueous mixture, and hydrated lipid membranes for molecular dynamics (MD) simulations, but also utilized it to delineate the aggregation and fusion of lipid vesicles using CG-MD simulations with multimillion particles. We have systematically parametrized the force-field for pure ethanol and its interactions with hydrated POPC and POPE model lipid membranes. In this process, we have successfully reproduced the bulk ethanol structure and concentration-dependent density of aqueous ethanol. To quantify the interaction of ethanol with lipid membranes, we have reproduced the transfer free energy of the ethanol molecule across the hydrated bilayers, and the concentration-dependent distribution of ethanol molecules across the lipid bilayers. After having acceptable force-field parameters for ethanol-membrane interactions, we have checked the effect of ethanol toward the vesicles comprising POPC lipids. We observe a rapid increase in the size of the POPC lipid vesicles with increasing amounts of ethanol up to 30 mol %. We unambiguously observe swelling and decrease in the thickness of the POPC vesicles with increasing amounts of ethanol up to 30 mol %, beyond which the vesicles begin to lose their integrity and rupture at higher mol % of ethanol. The fusion study of two vesicles demonstrates that fused vesicles can be obtained from 20 to 30 mol % of ethanol provided that they are brought closer than a critical distance at a particular mol %. The multivesicle simulations show that along with the increase in the sizes of vesicles the propensity of vesicle aggregation increases as the mol % of ethanol increases.
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Affiliation(s)
- Hemant K Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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10
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Liu Y, Zhang D, Zhang Y, Tang Y, Xu L, He H, Wu J, Zheng J. Molecular Dynamics Simulations of Cholesterol Effects on the Interaction of hIAPP with Lipid Bilayer. J Phys Chem B 2020; 124:7830-7841. [DOI: 10.1021/acs.jpcb.0c05742] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Yonglan Liu
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Dong Zhang
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Yanxian Zhang
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Yijing Tang
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Lijian Xu
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices College of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, P. R. China
| | - Huacheng He
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325027, P. R. China
| | - Jiang Wu
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P. R. China
| | - Jie Zheng
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
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11
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Kumari P, Kashyap HK. DMSO induced dehydration of heterogeneous lipid bilayers and its impact on their structures. J Chem Phys 2019; 151:215103. [DOI: 10.1063/1.5127852] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Pratibha Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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12
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Roux M, Bonnet V, Djedaïni-Pilard F. Ordering of Saturated and Unsaturated Lipid Membranes near Their Phase Transitions Induced by an Amphiphilic Cyclodextrin and Cholesterol. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:14376-14387. [PMID: 31564102 DOI: 10.1021/acs.langmuir.9b02082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
When inserted in membranes of dimyristoyl phosphatidylcholine (DMPC), methylated β-cyclodextrins with one (TrimβMLC) or two (TrimβDLC) lauryl acyl chains grafted onto the hydrophilic cavity exert a "cholesterol-like ordering effect", by straightening the acyl chains in the fluid phase at temperatures near the chain melting transition. This effect may be related to pretransitional events such as the "anomalous swelling" known to occur with saturated phosphatidylcholine membranes. To investigate this model, order profiles and bilayer thicknesses of DMPC and unsaturated 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) membranes containing amphiphilic cyclodextrins or cholesterol were determined by deuterium NMR. The pure lipid membranes display both a qualitatively similar chain ordering upon cooling in the fluid phase, more important at the chain extremity, which gets more pronounced near their fluid-to-gel transitions. Both membranes show a bilayer thickness increase by ∼0.5 Å just above their transition, as observed previously with saturated phosphatidylcholines of various chain lengths. Membrane-insertion of 5% TrimβMLC or cholesterol induces an important ordering of the DMPC acyl chains just above the transition, which is also more pronounced at the chain extremity. There is an additional increase of the bilayer thickness, most probably due to a deep insertion of these amphiphilic molecules, facilitated by increased bilayer softness in the anomalous swelling regime. These effects are more important with TrimβMLC than with cholesterol. By contrast, no enhanced acyl chain ordering was observed when approaching the transition of TrimβMLC-containing POPC membranes, as a possible consequence of an eventual lack of anomalous swelling in unsaturated lipid membranes. Insertion of higher concentrations of TrimβMLC was found to induce a magnetic orientation of the DMPC membranes in the fluid phase with 10% of this derivative, coupled with the appearance of a broad isotropic component when the concentration is raised to 20%. No membrane orientation or isotropic component was detected with TrimβMLC-containing POPC membranes.
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Affiliation(s)
- Michel Roux
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS , Université Paris-Sud, Université Paris-Saclay , F-91198 Gif-sur-Yvette cedex , France
| | - Véronique Bonnet
- LG2A, UMR7378 , Université de Picardie Jules Verne , F-80039 Amiens , France
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13
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Kumari P, Kumari M, Kashyap HK. Counter-effects of Ethanol and Cholesterol on the Heterogeneous PSM–POPC Lipid Membrane: A Molecular Dynamics Simulation Study. J Phys Chem B 2019; 123:9616-9628. [DOI: 10.1021/acs.jpcb.9b07107] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Pratibha Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Monika Kumari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Hemant K. Kashyap
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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14
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Borcik CG, Versteeg DB, Wylie BJ. An Inward-Rectifier Potassium Channel Coordinates the Properties of Biologically Derived Membranes. Biophys J 2019; 116:1701-1718. [PMID: 31010661 DOI: 10.1016/j.bpj.2019.03.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 03/20/2019] [Accepted: 03/25/2019] [Indexed: 12/13/2022] Open
Abstract
KirBac1.1 is a prokaryotic inward-rectifier K+ channel from Burkholderia pseudomallei. It shares the common inward-rectifier K+ channel fold with eukaryotic channels, including conserved lipid-binding pockets. Here, we show that KirBac1.1 changes the phase properties and dynamics of the surrounding bilayer. KirBac1.1 was reconstituted into vesicles composed of 13C-enriched biological lipids. Two-dimensional liquid-state and solid-state NMR experiments were used to assign lipid 1H and 13C chemical shifts as a function of lipid identity and conformational degrees of freedom. A solid-state NMR temperature series reveals that KirBac1.1 lowers the primary thermotropic phase transition of Escherichia coli lipid membranes while introducing both fluidity and internal lipid order into the fluid phases. In B. thailandensis liposomes, the bacteriohopanetetrol hopanoid, and potentially ornithine lipids, introduce a similar primary lipid-phase transition and liquid-ordered properties. Adding KirBac1.1 to B. thailandensis lipids increases B. thailandensis lipid fluidity while preserving internal lipid order. This synergistic effect of KirBac1.1 in bacteriohopanetetrol-rich membranes has implications for bilayer dynamic structure. If membrane proteins can anneal lipid translational degrees of freedom while preserving internal order, it could offer an explanation to the nature of liquid-ordered protein-lipid organization in vivo.
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Affiliation(s)
- Collin G Borcik
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas
| | - Derek B Versteeg
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas
| | - Benjamin J Wylie
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas.
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15
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Shahane G, Ding W, Palaiokostas M, Orsi M. Physical properties of model biological lipid bilayers: insights from all-atom molecular dynamics simulations. J Mol Model 2019; 25:76. [PMID: 30806797 DOI: 10.1007/s00894-019-3964-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 02/07/2019] [Indexed: 02/04/2023]
Abstract
The physical properties of lipid bilayers are sensitive to the specific type and composition of the lipids that make up the many different types of cell membranes. Studying model bilayers of representative heterogeneous compositions can provide key insights into membrane functionality. In this work, we use atomistic molecular dynamics simulations to characterize key properties in a number of bilayer membranes of varying composition. We first examine basic properties, such as lipid area, volume, and bilayer thickness, of simple, homogeneous bilayers comprising several lipid types, which are prevalent in biological membranes. Such lipids are then used in simulations of heterogeneous systems representative of bacterial, mammalian, and cancer membranes. Our analysis is especially focused on depth-dependent, transmembrane profiles; in particular, we calculate lateral pressure and dipole potential profiles, two fundamental properties which play key roles in a large number of biological functions.
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Affiliation(s)
- Ganesh Shahane
- Institute of Bioengineering, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Wei Ding
- School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Michail Palaiokostas
- School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Mario Orsi
- Department of Applied Sciences, University of the West of England, Coldharbour Lane, Bristol, BS16 1QY, UK.
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16
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Molugu TR, Brown MF. Cholesterol Effects on the Physical Properties of Lipid Membranes Viewed by Solid-state NMR Spectroscopy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1115:99-133. [PMID: 30649757 DOI: 10.1007/978-3-030-04278-3_5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In this chapter, we review the physical properties of lipid/cholesterol mixtures involving studies of model membranes using solid-state NMR spectroscopy. The approach allows one to quantify the average membrane structure, fluctuations, and elastic deformation upon cholesterol interaction. Emphasis is placed on understanding the membrane structural deformation and emergent fluctuations at an atomistic level. Lineshape measurements using solid-state NMR spectroscopy give equilibrium structural properties, while relaxation time measurements study the molecular dynamics over a wide timescale range. The equilibrium properties of glycerophospholipids, sphingolipids, and their binary and tertiary mixtures with cholesterol are accessible. Nonideal mixing of cholesterol with other lipids explains the occurrence of liquid-ordered domains. The entropic loss upon addition of cholesterol to sphingolipids is less than for glycerophospholipids, and may drive formation of lipid rafts. The functional dependence of 2H NMR spin-lattice relaxation (R 1Z) rates on segmental order parameters (S CD) for lipid membranes is indicative of emergent viscoelastic properties. Addition of cholesterol shows stiffening of the bilayer relative to the pure lipids and this effect is diminished for lanosterol. Opposite influences of cholesterol and detergents on collective dynamics and elasticity at an atomistic scale can potentially affect lipid raft formation in cellular membranes.
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Affiliation(s)
- Trivikram R Molugu
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, USA
| | - Michael F Brown
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, USA. .,Department of Physics, University of Arizona, Tucson, AZ, USA.
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17
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Elola MD, Rodriguez J. Influence of Cholesterol on the Dynamics of Hydration in Phospholipid Bilayers. J Phys Chem B 2018; 122:5897-5907. [PMID: 29742895 DOI: 10.1021/acs.jpcb.8b00360] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We investigate the dynamics of interfacial waters in dipalmitoylphosphatidylcholine (DPPC) bilayers upon the addition of cholesterol, by molecular dynamics simulations. Our data reveal that the inclusion of cholesterol modifies the membrane aqueous interfacial dynamics: waters diffuse faster, their rotational decay time is shorter, and the DPPC/water hydrogen bond dynamics relaxes faster than in the pure DPPC membrane. The observed acceleration of the translational water dynamics agrees with recent experimental results, in which, by means of NMR techniques, an increment of the surface water diffusivity is measured upon the addition of cholesterol. A microscopic analysis of the lipid/water hydrogen bond network at the interfacial region suggests that the mechanism underlying the observed water mobility enhancement is given by the rupture of a fraction of interlipid water bridge hydrogen bonds connecting two different DPPC molecules, concomitant to the formation of new lipid/solvent bonds, whose dynamics is faster than that of the former. The consideration of a simple two-state model for the decay of the hydrogen bond correlation function yielded excellent results, obtaining two well-separated characteristic time scales: a slow one (∼250 ps) associated with bonds linking two DPPC molecules, and a fast one (∼15 ps), related to DPPC/solvent bonds.
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Affiliation(s)
- M Dolores Elola
- Departamento de Física , Comisión Nacional de Energía Atómica , Av Libertador 8250, 1429 Buenos Aires , Argentina
| | - Javier Rodriguez
- Departamento de Física , Comisión Nacional de Energía Atómica , Av Libertador 8250, 1429 Buenos Aires , Argentina.,ECyT , UNSAM , Martín de Irigoyen 3100, 1650 San Martín, Provincia de Buenos Aires , Argentina
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18
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Leng X, Kinnun JJ, Cavazos AT, Canner SW, Shaikh SR, Feller SE, Wassall SR. All n-3 PUFA are not the same: MD simulations reveal differences in membrane organization for EPA, DHA and DPA. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2018; 1860:1125-1134. [PMID: 29305832 PMCID: PMC5963985 DOI: 10.1016/j.bbamem.2018.01.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 12/19/2017] [Accepted: 01/01/2018] [Indexed: 01/01/2023]
Abstract
Eicosapentaenoic (EPA, 20:5), docosahexaenoic (DHA, 22:6) and docosapentaenoic (DPA, 22:5) acids are omega-3 polyunsaturated fatty acids (n-3 PUFA) obtained from dietary consumption of fish oils that potentially alleviate the symptoms of a range of chronic diseases. We focus here on the plasma membrane as a site of action and investigate how they affect molecular organization when taken up into a phospholipid. All atom MD simulations were performed to compare 1-stearoyl-2-eicosapentaenoylphosphatylcholine (EPA-PC, 18:0-20:5PC), 1-stearoyl-2-docosahexaenoylphosphatylcholine (DHA-PC, 18:0-22:6PC), 1-stearoyl-2-docosapentaenoylphosphatylcholine (DPA-PC, 18:0-22:5PC) and, as a monounsaturated control, 1-stearoyl-2-oleoylphosphatidylcholine (OA-PC, 18:0-18:1PC) bilayers. They were run in the absence and presence of 20mol% cholesterol. Multiple double bonds confer high disorder on all three n-3 PUFA. The different number of double bonds and chain length for each n-3 PUFA moderates the reduction in membrane order exerted (compared to OA-PC, S¯CD=0.152). EPA-PC (S¯CD=0.131) is most disordered, while DPA-PC (S¯CD=0.140) is least disordered. DHA-PC (S¯CD=0.139) is, within uncertainty, the same as DPA-PC. Following the addition of cholesterol, order in EPA-PC (S¯CD=0.169), DHA-PC (S¯CD=0.178) and DPA-PC (S¯CD=0.182) is increased less than in OA-PC (S¯CD=0.214). The high disorder of n-3 PUFA is responsible, preventing the n-3 PUFA-containing phospholipids from packing as close to the rigid sterol as the monounsaturated control. Our findings establish that EPA, DHA and DPA are not equivalent in their interactions within membranes, which possibly contributes to differences in clinical efficacy.
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Affiliation(s)
- Xiaoling Leng
- Department of Physics, IUPUI, Indianapolis, IN 46202-3273, United States
| | - Jacob J Kinnun
- Department of Physics, IUPUI, Indianapolis, IN 46202-3273, United States
| | - Andres T Cavazos
- Department of Physics, IUPUI, Indianapolis, IN 46202-3273, United States
| | - Samuel W Canner
- Department of Physics, IUPUI, Indianapolis, IN 46202-3273, United States; Department of Computer Science and Information Science, IUPUI, Indianapolis, IN 46202-5132, United States
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Scott E Feller
- Department of Chemistry, Wabash College, Crawfordsville, IN 47933, United States
| | - Stephen R Wassall
- Department of Physics, IUPUI, Indianapolis, IN 46202-3273, United States.
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19
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Della Ripa LA, Petros ZA, Cioffi AG, Piehl DW, Courtney JM, Burke MD, Rienstra CM. Solid-State NMR of highly 13C-enriched cholesterol in lipid bilayers. Methods 2018; 138-139:47-53. [PMID: 29366688 DOI: 10.1016/j.ymeth.2018.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/16/2018] [Accepted: 01/18/2018] [Indexed: 12/25/2022] Open
Abstract
Cholesterol (Chol) is vital for cell function as it is essential to a myriad of biochemical and biophysical processes. The atomistic details of Chol's interactions with phospholipids and proteins is therefore of fundamental interest, and NMR offers unique opportunities to interrogate these properties at high resolution. Towards this end, here we describe approaches for examining the structure and dynamics of Chol in lipid bilayers using high levels of 13C enrichment in combination with magic-angle spinning (MAS) methods. We quantify the incorporation levels and demonstrate high sensitivity and resolution in 2D 13C-13C and 1H-13C spectra, enabling de novo assignments and site-resolved order parameter measurements obtained in a fraction of the time required for experiments with natural abundance sterols. We envision many potential future applications of these methods to study sterol interactions with drugs, lipids and proteins.
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Affiliation(s)
- Lisa A Della Ripa
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Zoe A Petros
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Alexander G Cioffi
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Dennis W Piehl
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Joseph M Courtney
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Martin D Burke
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA; Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA; Carle-Illinois College of Medicine, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA.
| | - Chad M Rienstra
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA; Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA; Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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20
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Stereospecific Interactions of Cholesterol in a Model Cell Membrane: Implications for the Membrane Dipole Potential. J Membr Biol 2018; 251:507-519. [DOI: 10.1007/s00232-018-0016-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 01/25/2018] [Indexed: 12/11/2022]
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21
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Molugu TR, Lee S, Brown MF. Concepts and Methods of Solid-State NMR Spectroscopy Applied to Biomembranes. Chem Rev 2017; 117:12087-12132. [PMID: 28906107 DOI: 10.1021/acs.chemrev.6b00619] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Concepts of solid-state NMR spectroscopy and applications to fluid membranes are reviewed in this paper. Membrane lipids with 2H-labeled acyl chains or polar head groups are studied using 2H NMR to yield knowledge of their atomistic structures in relation to equilibrium properties. This review demonstrates the principles and applications of solid-state NMR by unifying dipolar and quadrupolar interactions and highlights the unique features offered by solid-state 2H NMR with experimental illustrations. For randomly oriented multilamellar lipids or aligned membranes, solid-state 2H NMR enables direct measurement of residual quadrupolar couplings (RQCs) due to individual C-2H-labeled segments. The distribution of RQC values gives nearly complete profiles of the segmental order parameters SCD(i) as a function of acyl segment position (i). Alternatively, one can measure residual dipolar couplings (RDCs) for natural abundance lipid samples to obtain segmental SCH order parameters. A theoretical mean-torque model provides acyl-packing profiles representing the cumulative chain extension along the normal to the aqueous interface. Equilibrium structural properties of fluid bilayers and various thermodynamic quantities can then be calculated, which describe the interactions with cholesterol, detergents, peptides, and integral membrane proteins and formation of lipid rafts. One can also obtain direct information for membrane-bound peptides or proteins by measuring RDCs using magic-angle spinning (MAS) in combination with dipolar recoupling methods. Solid-state NMR methods have been extensively applied to characterize model membranes and membrane-bound peptides and proteins, giving unique information on their conformations, orientations, and interactions in the natural liquid-crystalline state.
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Affiliation(s)
- Trivikram R Molugu
- Department of Chemistry & Biochemistry and ‡Department of Physics, University of Arizona , Tucson, Arizona 85721, United States
| | - Soohyun Lee
- Department of Chemistry & Biochemistry and ‡Department of Physics, University of Arizona , Tucson, Arizona 85721, United States
| | - Michael F Brown
- Department of Chemistry & Biochemistry and ‡Department of Physics, University of Arizona , Tucson, Arizona 85721, United States
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22
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Haralampiev I, Scheidt HA, Huster D, Müller P. The Potential of α-Spinasterol to Mimic the Membrane Properties of Natural Cholesterol. Molecules 2017; 22:molecules22081390. [PMID: 28829376 PMCID: PMC6152097 DOI: 10.3390/molecules22081390] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 08/18/2017] [Accepted: 08/19/2017] [Indexed: 01/07/2023] Open
Abstract
Sterols play a unique role for the structural and dynamical organization of membranes. The current study reports data on the membrane properties of the phytosterol (3β,5α,22E)-stigmasta-7,22-dien-3-β-ol (α-spinasterol), which represents an important component of argan oil and have not been investigated so far in molecular detail. In particular, the impact of α-spinasterol on the structure and organization of lipid membranes was investigated and compared with those of cholesterol. Various membrane parameters such as the molecular packing of the phospholipid fatty acyl chains, the membrane permeability toward polar molecules, and the formation of lateral membrane domains were studied. The experiments were performed on lipid vesicles using methods of NMR spectroscopy and fluorescence spectroscopy and microscopy. The results show that α-spinasterol resembles the membrane behavior of cholesterol to some degree.
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Affiliation(s)
- Ivan Haralampiev
- Department of Biology, Humboldt-Universität zu Berlin, Invalidenstr. 42, D-10115 Berlin, Germany.
| | - Holger A Scheidt
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany.
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany.
| | - Peter Müller
- Department of Biology, Humboldt-Universität zu Berlin, Invalidenstr. 42, D-10115 Berlin, Germany.
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23
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Hilsch M, Haralampiev I, Müller P, Huster D, Scheidt HA. Membrane properties of hydroxycholesterols related to the brain cholesterol metabolism. Beilstein J Org Chem 2017; 13:720-727. [PMID: 28503207 PMCID: PMC5405690 DOI: 10.3762/bjoc.13.71] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/04/2017] [Indexed: 12/11/2022] Open
Abstract
Compared to cholesterol, hydroxycholesterols contain an additional hydroxy group in the alkyl chain and are able to efficiently cross the brain-blood barrier. Therefore, they are responsible for the sterol transfer between brain and circulation. The current study compares the membrane properties of several hydroxycholesterols with those of cholesterol using 2H NMR spectroscopy, a membrane permeability assay, and fluorescence microscopy experiments. It is shown that hydroxycholesterols do not exert the unique impact on membrane properties characteristic for cholesterol with regard to the influence on lipid chain order, membrane permeability and formation of lateral domains.
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Affiliation(s)
- Malte Hilsch
- Department of Biology, Humboldt University Berlin, Invalidenstraße 43, D-10115 Berlin, Germany
| | - Ivan Haralampiev
- Department of Biology, Humboldt University Berlin, Invalidenstraße 43, D-10115 Berlin, Germany
| | - Peter Müller
- Department of Biology, Humboldt University Berlin, Invalidenstraße 43, D-10115 Berlin, Germany
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16–18, D-04107 Leipzig, Germany
| | - Holger A Scheidt
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16–18, D-04107 Leipzig, Germany
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24
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Amaro M, Reina F, Hof M, Eggeling C, Sezgin E. Laurdan and Di-4-ANEPPDHQ probe different properties of the membrane. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2017; 50:134004. [PMID: 29449744 PMCID: PMC5802044 DOI: 10.1088/1361-6463/aa5dbc] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 01/02/2017] [Accepted: 02/02/2017] [Indexed: 05/22/2023]
Abstract
Lipid packing is a crucial feature of cellular membranes. Quantitative analysis of membrane lipid packing can be achieved using polarity sensitive probes whose emission spectrum depends on the lipid packing. However, detailed insights into the exact mechanisms that cause the changes in the spectra are necessary to interpret experimental fluorescence emission data correctly. Here, we analysed frequently used polarity sensitive probes, Laurdan and di-4-ANEPPDHQ, to test whether the underlying physical mechanisms of their spectral changes are the same and, thus, whether they report on the same physico-chemical properties of the cell membrane. Steady-state spectra as well as time-resolved emission spectra of the probes in solvents and model membranes revealed that they probe different properties of the lipid membrane. Our findings are important for the application of these dyes in cell biology.
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Affiliation(s)
- Mariana Amaro
- Department of Biophysical Chemistry, J. Heyrovský Institute of Physical Chemistry of the C.A.S, v.v.i., Dolejskova 3, 182 23 Prague, Czechia
| | - Francesco Reina
- MRC Human Immunology Unit, OX39DS, University of Oxford, Oxford, United Kingdom
| | - Martin Hof
- Department of Biophysical Chemistry, J. Heyrovský Institute of Physical Chemistry of the C.A.S, v.v.i., Dolejskova 3, 182 23 Prague, Czechia
| | - Christian Eggeling
- MRC Human Immunology Unit, OX39DS, University of Oxford, Oxford, United Kingdom
| | - Erdinc Sezgin
- MRC Human Immunology Unit, OX39DS, University of Oxford, Oxford, United Kingdom
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25
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Amaro M, Filipe HAL, Prates Ramalho JP, Hof M, Loura LMS. Fluorescence of nitrobenzoxadiazole (NBD)-labeled lipids in model membranes is connected not to lipid mobility but to probe location. Phys Chem Chem Phys 2016; 18:7042-54. [PMID: 26727975 DOI: 10.1039/c5cp05238f] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Nitrobenzoxadiazole (NBD)-labeled lipids are popular fluorescent membrane probes. However, the understanding of important aspects of the photophysics of NBD remains incomplete, including the observed shift in the emission spectrum of NBD-lipids to longer wavelengths following excitation at the red edge of the absorption spectrum (red-edge excitation shift or REES). REES of NBD-lipids in membrane environments has been previously interpreted as reflecting restricted mobility of solvent surrounding the fluorophore. However, this requires a large change in the dipole moment (Δμ) of NBD upon excitation. Previous calculations of the value of Δμ of NBD in the literature have been carried out using outdated semi-empirical methods, leading to conflicting values. Using up-to-date density functional theory methods, we recalculated the value of Δμ and verified that it is rather small (∼2 D). Fluorescence measurements confirmed that the value of REES is ∼16 nm for 1,2-dioleoyl-sn-glycero-3-phospho-l-serine-N-(NBD) (NBD-PS) in dioleoylphosphatidylcholine vesicles. However, the observed shift is independent of both the temperature and the presence of cholesterol and is therefore insensitive to the mobility and hydration of the membrane. Moreover, red-edge excitation leads to an increased contribution of the decay component with a shorter lifetime, whereas time-resolved emission spectra of NBD-PS displayed an atypical blue shift following excitation. This excludes restrictions to solvent relaxation as the cause of the measured REES and TRES of NBD, pointing instead to the heterogeneous transverse location of probes as the origin of these effects. The latter hypothesis was confirmed by molecular dynamics simulations, from which the calculated heterogeneity of the hydration and location of NBD correlated with the measured fluorescence lifetimes/REES. Globally, our combination of theoretical and experiment-based techniques has led to a considerably improved understanding of the photophysics of NBD and a reinterpretation of its REES in particular.
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Affiliation(s)
- Mariana Amaro
- Department of Biophysical Chemistry, J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v.v.i., Dolejskova 3, 182 23 Prague, Czech Republic.
| | - Hugo A L Filipe
- Centro de Química de Coimbra, Largo D. Dinis, Rua Larga, 3004-535 Coimbra, Portugal. and Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, Largo D. Dinis, Rua Larga, 3004-535 Coimbra, Portugal and Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004-504 Coimbra, Portugal
| | - J P Prates Ramalho
- Departamento de Química and Centro de Química de Évora, Escola de Ciências e Tecnologia, Universidade de Évora, Rua Romão Ramalho, 59, 7000-671 Évora, Portugal
| | - Martin Hof
- Department of Biophysical Chemistry, J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v.v.i., Dolejskova 3, 182 23 Prague, Czech Republic.
| | - Luís M S Loura
- Centro de Química de Coimbra, Largo D. Dinis, Rua Larga, 3004-535 Coimbra, Portugal. and Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004-504 Coimbra, Portugal and Faculdade de Farmácia, Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
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26
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Marquardt D, Heberle FA, Greathouse DV, Koeppe RE, Standaert RF, Van Oosten BJ, Harroun TA, Kinnun JJ, Williams JA, Wassall SR, Katsaras J. Lipid bilayer thickness determines cholesterol's location in model membranes. SOFT MATTER 2016; 12:9417-9428. [PMID: 27801465 DOI: 10.1039/c6sm01777k] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Cholesterol is an essential biomolecule of animal cell membranes, and an important precursor for the biosynthesis of certain hormones and vitamins. It is also thought to play a key role in cell signaling processes associated with functional plasma membrane microdomains (domains enriched in cholesterol), commonly referred to as rafts. In all of these diverse biological phenomena, the transverse location of cholesterol in the membrane is almost certainly an important structural feature. Using a combination of neutron scattering and solid-state 2H NMR, we have determined the location and orientation of cholesterol in phosphatidylcholine (PC) model membranes having fatty acids of different lengths and degrees of unsaturation. The data establish that cholesterol reorients rapidly about the bilayer normal in all the membranes studied, but is tilted and forced to span the bilayer midplane in the very thin bilayers. The possibility that cholesterol lies flat in the middle of bilayers, including those made from PC lipids containing polyunsaturated fatty acids (PUFAs), is ruled out. These results support the notion that hydrophobic thickness is the primary determinant of cholesterol's location in membranes.
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Affiliation(s)
- Drew Marquardt
- Department of Physics, Brock University, St. Catharines, Ontario L2S 3A1, Canada and Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Frederick A Heberle
- The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee 37996, USA and Joint Institute for Biological Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA and Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
| | - Denise V Greathouse
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Roger E Koeppe
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Robert F Standaert
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA and Department of Biochemistry and Cellular & Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Brad J Van Oosten
- Department of Physics, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Thad A Harroun
- Department of Physics, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Jacob J Kinnun
- Department of Physics, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana 46202, USA.
| | - Justin A Williams
- Department of Physics, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana 46202, USA.
| | - Stephen R Wassall
- Department of Physics, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana 46202, USA.
| | - John Katsaras
- Department of Physics, Brock University, St. Catharines, Ontario L2S 3A1, Canada and The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee 37996, USA and Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. and Shull Wollan Center-a Joint Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA and Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
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27
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Vogel A, Scheidt HA, Baek DJ, Bittman R, Huster D. Structure and dynamics of the aliphatic cholesterol side chain in membranes as studied by (2)H NMR spectroscopy and molecular dynamics simulation. Phys Chem Chem Phys 2016; 18:3730-8. [PMID: 26762541 DOI: 10.1039/c5cp05084g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cholesterol is an evolutionarily highly optimized molecule particularly known for its ability to condense the phospholipids in cellular membranes. Until recently, the accompanying increase in the chain order of the surrounding phospholipids was attributed to the planar and rigid tetracyclic ring structure of cholesterol. However, detailed investigations of cholesterol's aliphatic side chain demonstrated that this side chain is responsible for approximately half of the condensation effect. Therefore, we investigated the structure and dynamics of the aliphatic side chain of cholesterol using (2)H solid-state nuclear magnetic resonance (NMR) spectroscopy and microsecond timescale all-atom molecular dynamics (MD) simulations in four different model membranes: POPC, DPPC, PSM, and POPC/PSM (1 : 1 mol/mol) and at three different temperatures: 5 °C, 37 °C, and 50 °C. A cholesterol variant, in which 11 hydrogens of the aliphatic side chain were exchanged for deuterium, was used and the respective (2)H NMR spectra confirmed the axially asymmetric rotational diffusion of cholesterol in DPPC and PSM. Furthermore, NMR spectra indicated that some hydrogens showed an unexpected magnetic inequivalency. This finding was confirmed by all-atom molecular dynamics simulations and detailed analysis revealed that the hydrogens of the methylene groups at C22, C23, and C24 are magnetically inequivalent. This inequivalency is caused by steric clashes of the aliphatic side chain with the ring structure of cholesterol as well as the branched C21 methyl group. These excluded volume effects result in reduced conformational flexibility of the aliphatic side chain of cholesterol and explain its high order (order parameter of 0.78 for chain motions) and large contribution to the condensation effect. Additionally, the motional pattern of the side chain becomes highly anisotropic such that it shows larger fluctuations perpendicular to the ring plane of cholesterol with a biaxiality of the distribution of 0.046. Overall, our results shed light on the mechanism how the aliphatic side chain is able to contribute about half of the condensation effect of cholesterol.
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Affiliation(s)
- Alexander Vogel
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04275 Leipzig, Germany.
| | - Holger A Scheidt
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04275 Leipzig, Germany.
| | - Dong Jae Baek
- College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Jeonnam, Republic of Korea and Department of Chemistry and Biochemistry, Queens College of the City University of New York, Flushing, NY 11367-1597, USA
| | - Robert Bittman
- Department of Chemistry and Biochemistry, Queens College of the City University of New York, Flushing, NY 11367-1597, USA
| | - Daniel Huster
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04275 Leipzig, Germany.
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Marquardt D, Kučerka N, Wassall SR, Harroun TA, Katsaras J. Cholesterol's location in lipid bilayers. Chem Phys Lipids 2016; 199:17-25. [DOI: 10.1016/j.chemphyslip.2016.04.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 04/01/2016] [Accepted: 04/02/2016] [Indexed: 02/07/2023]
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29
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Usuda H, Hishida M, Yamamura Y, Saito K. Contrasting Effects of a Rigid Core and an Alkyl Chain in nCB on the Phase Behavior of Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:5966-5972. [PMID: 27219128 DOI: 10.1021/acs.langmuir.6b00774] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Molecules incorporated into biomembranes often bear both a core and an alkyl chain in a single molecule (e.g., sterols). To clarify the effects of these two parts of a molecule, the phase behavior of a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayer containing 4-n-alkyl-4'-cyanobiphenyl (nCB) (n = 0-8) was investigated. The trends of the main transition temperature (Tm) with respect to n and of the pretransition temperature (Tp) with respect to nCB content changed at n = 3. It was therefore suggested that the two parts of the molecule had opposing effects on the phase behavior of DPPC bilayers. The core appears to perturb molecular ordering in the gel phase and lowers Tm (like cholesterol), while alkyl chains appear to order the lipids in the gel phase and raise Tm (like n-alkanes). In addition, Tm exhibits the so-called odd-even effect based on the alkyl chain length of the minor component, nCB. Depending on the value of n, the variation in Tp was dependent on the additive content, although the pretransition was rarely observed at high contents.
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Affiliation(s)
- Hatsuho Usuda
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba , Tsukuba, Ibaraki 305-8571, Japan
| | - Mafumi Hishida
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba , Tsukuba, Ibaraki 305-8571, Japan
| | - Yasuhisa Yamamura
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba , Tsukuba, Ibaraki 305-8571, Japan
| | - Kazuya Saito
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba , Tsukuba, Ibaraki 305-8571, Japan
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Molugu TR, Brown MF. Cholesterol-induced suppression of membrane elastic fluctuations at the atomistic level. Chem Phys Lipids 2016; 199:39-51. [PMID: 27154600 DOI: 10.1016/j.chemphyslip.2016.05.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/29/2016] [Accepted: 05/02/2016] [Indexed: 12/14/2022]
Abstract
Applications of solid-state NMR spectroscopy for investigating the influences of lipid-cholesterol interactions on membrane fluctuations are reviewed in this paper. Emphasis is placed on understanding the energy landscapes and fluctuations at an emergent atomistic level. Solid-state (2)H NMR spectroscopy directly measures residual quadrupolar couplings (RQCs) due to individual C-(2)H labeled segments of the lipid molecules. Moreover, residual dipolar couplings (RDCs) of (13)C-(1)H bonds are obtained in separated local-field NMR spectroscopy. The distributions of RQC or RDC values give nearly complete profiles of the order parameters as a function of acyl segment position. Measured equilibrium properties of glycerophospholipids and sphingolipids including their binary and tertiary mixtures with cholesterol show unequal mixing associated with liquid-ordered domains. The entropic loss upon addition of cholesterol to sphingolipids is less than for glycerophospholipids and may drive the formation of lipid rafts. In addition relaxation time measurements enable one to study the molecular dynamics over a wide time-scale range. For (2)H NMR the experimental spin-lattice (R1Z) relaxation rates follow a theoretical square-law dependence on segmental order parameters (SCD) due to collective slow dynamics over mesoscopic length scales. The functional dependence for the liquid-crystalline lipid membranes is indicative of viscoelastic properties as they emerge from atomistic-level interactions. A striking decrease in square-law slope upon addition of cholesterol denotes stiffening relative to the pure lipid bilayers that is diminished in the case of lanosterol. Measured equilibrium properties and relaxation rates infer opposite influences of cholesterol and detergents on collective dynamics and elasticity at an atomistic scale that potentially affects lipid raft formation in cellular membranes.
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Affiliation(s)
- Trivikram R Molugu
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Michael F Brown
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA; Department of Physics, University of Arizona, Tucson, AZ 85721, USA.
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31
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Zamora-Carreras H, Strandberg E, Mühlhäuser P, Bürck J, Wadhwani P, Jiménez MÁ, Bruix M, Ulrich AS. Alanine scan and (2)H NMR analysis of the membrane-active peptide BP100 point to a distinct carpet mechanism of action. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1328-38. [PMID: 26975251 DOI: 10.1016/j.bbamem.2016.03.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 02/23/2016] [Accepted: 03/10/2016] [Indexed: 10/22/2022]
Abstract
The short membrane-active peptide BP100 [KKLFKKILKYL-NH2] is known as an effective antimicrobial and cell penetrating agent. For a functional alanine scan each of the 11 amino acids was replaced with deuterated Ala-d3, one at a time. MIC assays showed that a substitution of Lys did not affect the antimicrobial activity, but it decreased when a hydrophobic residue was replaced. In most cases, a reduction in hydrophobicity led to a decrease in hemolysis, and some peptide analogues had an improved therapeutic index. Circular dichroism showed that BP100 folds as an amphiphilic α-helix in a bilayer. Its alignment was determined from (2)H NMR in oriented membranes of different composition. The azimuthal rotation angle was the same under all conditions, but the average helix tilt angle and the dynamical behavior of the peptide varied in a systematic manner. In POPC/POPG bilayers, with a negative spontaneous curvature, the peptide was found to lie flat on the bilayer surface, and with little wobble. In DMPC/DMPG, with a positive spontaneous curvature, BP100 at higher concentrations became tilted obliquely into the membrane, with the uncharged C-terminus inserted more deeply into the lipid bilayer, experiencing significant fluctuations in tilt angle. In DMPC/DMPG/lyso-MPC, with a pronounced positive spontaneous curvature, the helix tilted even further and became even more mobile. The 11-mer BP100 is obviously too short to form transmembrane pores. We conclude that BP100 operates via a carpet mechanism, whereby the C-terminus gets inserted into the hydrophobic core of the bilayer, which leads to membrane perturbation and induces transient permeability.
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Affiliation(s)
| | - Erik Strandberg
- Karlsruhe Institute for Technology (KIT), Institute for Biological Interfaces (IBG-2), POB 3640, 76021 Karlsruhe, Germany
| | - Philipp Mühlhäuser
- Karlsruhe Institute for Technology (KIT), Institute for Biological Interfaces (IBG-2), POB 3640, 76021 Karlsruhe, Germany
| | - Jochen Bürck
- Karlsruhe Institute for Technology (KIT), Institute for Biological Interfaces (IBG-2), POB 3640, 76021 Karlsruhe, Germany
| | - Parvesh Wadhwani
- Karlsruhe Institute for Technology (KIT), Institute for Biological Interfaces (IBG-2), POB 3640, 76021 Karlsruhe, Germany
| | - M Ángeles Jiménez
- Instituto de Química Física "Rocasolano", CSIC, Serrano 119, 28006 Madrid, Spain
| | - Marta Bruix
- Instituto de Química Física "Rocasolano", CSIC, Serrano 119, 28006 Madrid, Spain
| | - Anne S Ulrich
- Karlsruhe Institute for Technology (KIT), Institute for Biological Interfaces (IBG-2), POB 3640, 76021 Karlsruhe, Germany; KIT, Institute of Organic Chemistry and CFN, Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
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32
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Filippov AV, Kotenkov SA, Munavirov BV, Khaliullina AV, Gnezdilov OI, Antzutkin ON. Effect of curcumin on lateral diffusion in lipid bilayers. MENDELEEV COMMUNICATIONS 2016. [DOI: 10.1016/j.mencom.2016.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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33
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Interactions Between the Lipid Core and the Phospholipid Interface in Emulsions and Solid Lipid Nanoparticles. FOOD BIOPHYS 2015. [DOI: 10.1007/s11483-015-9413-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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34
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Leftin A, Molugu TR, Job C, Beyer K, Brown MF. Area per lipid and cholesterol interactions in membranes from separated local-field (13)C NMR spectroscopy. Biophys J 2015; 107:2274-86. [PMID: 25418296 DOI: 10.1016/j.bpj.2014.07.044] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 06/24/2014] [Accepted: 07/15/2014] [Indexed: 10/24/2022] Open
Abstract
Investigations of lipid membranes using NMR spectroscopy generally require isotopic labeling, often precluding structural studies of complex lipid systems. Solid-state (13)C magic-angle spinning NMR spectroscopy at natural isotopic abundance gives site-specific structural information that can aid in the characterization of complex biomembranes. Using the separated local-field experiment DROSS, we resolved (13)C-(1)H residual dipolar couplings that were interpreted with a statistical mean-torque model. Liquid-disordered and liquid-ordered phases were characterized according to membrane thickness and average cross-sectional area per lipid. Knowledge of such structural parameters is vital for molecular dynamics simulations, and provides information about the balance of forces in membrane lipid bilayers. Experiments were conducted with both phosphatidylcholine (dimyristoylphosphatidylcholine (DMPC) and palmitoyloleoylphosphatidylcholine (POPC)) and egg-yolk sphingomyelin (EYSM) lipids, and allowed us to extract segmental order parameters from the (13)C-(1)H residual dipolar couplings. Order parameters were used to calculate membrane structural quantities, including the area per lipid and bilayer thickness. Relative to POPC, EYSM is more ordered in the ld phase and experiences less structural perturbation upon adding 50% cholesterol to form the lo phase. The loss of configurational entropy is smaller for EYSM than for POPC, thus favoring its interaction with cholesterol in raftlike lipid systems. Our studies show that solid-state (13)C NMR spectroscopy is applicable to investigations of complex lipids and makes it possible to obtain structural parameters for biomembrane systems where isotope labeling may be prohibitive.
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Affiliation(s)
- Avigdor Leftin
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Trivikram R Molugu
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Constantin Job
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Klaus Beyer
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Michael F Brown
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona; Department of Physics, University of Arizona, Tucson, Arizona.
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35
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Matsumori N, Yamaguchi T, Maeta Y, Murata M. Orientation and Order of the Amide Group of Sphingomyelin in Bilayers Determined by Solid-State NMR. Biophys J 2015; 108:2816-24. [PMID: 26083921 PMCID: PMC4472221 DOI: 10.1016/j.bpj.2015.05.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 05/07/2015] [Accepted: 05/11/2015] [Indexed: 10/23/2022] Open
Abstract
Sphingomyelin (SM) and cholesterol (Chol) are considered essential for the formation of lipid rafts; however, the types of molecular interactions involved in this process, such as intermolecular hydrogen bonding, are not well understood. Since, unlike other phospholipids, SM is characterized by the presence of an amide group, it is essential to determine the orientation of the amide and its order in the lipid bilayers to understand the nature of the hydrogen bonds in lipid rafts. For this study, 1'-(13)C-2-(15)N-labeled and 2'-(13)C-2-(15)N-labeled SMs were prepared, and the rotational-axis direction and order parameters of the SM amide in bilayers were determined based on (13)C and (15)N chemical-shift anisotropies and intramolecular (13)C-(15)N dipole coupling constants. Results revealed that the amide orientation was minimally affected by Chol, whereas the order was enhanced significantly in its presence. Thus, Chol likely promotes the formation of an intermolecular hydrogen-bond network involving the SM amide without significantly changing its orientation, providing a higher order to the SM amide. To our knowledge, this study offers new insight into the significance of the SM amide orientation with regard to molecular recognition in lipid rafts, and therefore provides a deeper understanding of the mechanism of their formation.
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Affiliation(s)
- Nobuaki Matsumori
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, Japan.
| | - Toshiyuki Yamaguchi
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, Japan; Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Graduate School of Science, Osaka University, Osaka, Japan
| | - Yoshiko Maeta
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, Japan
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, Japan; Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Graduate School of Science, Osaka University, Osaka, Japan
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36
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Cui J, Matsuoka S, Kinoshita M, Matsumori N, Sato F, Murata M, Ando J, Yamakoshi H, Dodo K, Sodeoka M. Novel Raman-tagged sphingomyelin that closely mimics original raft-forming behavior. Bioorg Med Chem 2015; 23:2989-94. [PMID: 26026768 DOI: 10.1016/j.bmc.2015.05.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 05/03/2015] [Accepted: 05/05/2015] [Indexed: 01/07/2023]
Abstract
Three Raman probes of sphingomyelin (SM) were synthesized and evaluated for their applicability to imaging experiments. One probe containing a hydroxymethyl-1,3-butadiyne moiety in the polar head group showed strong scattering. The solid-state (2)H NMR spectra of this probe in oriented bilayer membrane revealed excellent compatibility with natural SM in phase behavior since the probe undergoes phase separation to form raft-like liquid ordered (Lo) domains in the raft-mimicking mixed bilayers.
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Affiliation(s)
- Jin Cui
- Department of Chemistry, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; JST, ERATO, Lipid Active Structure Project, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Project Research Centre for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Shigeru Matsuoka
- Department of Chemistry, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; JST, ERATO, Lipid Active Structure Project, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Project Research Centre for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Masanao Kinoshita
- Department of Chemistry, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; JST, ERATO, Lipid Active Structure Project, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Project Research Centre for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Nobuaki Matsumori
- Department of Chemistry, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Fuminori Sato
- JST, ERATO, Lipid Active Structure Project, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Project Research Centre for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Michio Murata
- Department of Chemistry, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; JST, ERATO, Lipid Active Structure Project, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan; Project Research Centre for Fundamental Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
| | - Jun Ando
- JST, ERATO, Sodeoka Live Cell Chemistry Project, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; AMED-CREST, AMED 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hiroyuki Yamakoshi
- JST, ERATO, Sodeoka Live Cell Chemistry Project, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kosuke Dodo
- JST, ERATO, Sodeoka Live Cell Chemistry Project, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; AMED-CREST, AMED 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mikiko Sodeoka
- JST, ERATO, Sodeoka Live Cell Chemistry Project, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; AMED-CREST, AMED 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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37
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Marbella LE, Yin B, Spence MM. Investigating the Order Parameters of Saturated Lipid Molecules under Various Curvature Conditions on Spherical Supported Lipid Bilayers. J Phys Chem B 2015; 119:4194-202. [DOI: 10.1021/jp510322t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lauren E. Marbella
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Bocheng Yin
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Megan M. Spence
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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38
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Robalo JR, Ramalho JPP, Huster D, Loura LMS. Influence of the sterol aliphatic side chain on membrane properties: a molecular dynamics study. Phys Chem Chem Phys 2015; 17:22736-48. [DOI: 10.1039/c5cp03097h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cholesterol provides best hydrophobic matching, induces maximal membrane ordering, and displays highest preference for saturated phospholipid acyl chains, among a homologous ser ies of sterols with side chains of varying lengths.
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Affiliation(s)
- João R. Robalo
- Centro de Química de Évora and Departamento de Química
- Escola de Ciências e Tecnologia
- Universidade de Évora
- P-7000-671 Évora
- Portugal
| | - J. P. Prates Ramalho
- Centro de Química de Évora and Departamento de Química
- Escola de Ciências e Tecnologia
- Universidade de Évora
- P-7000-671 Évora
- Portugal
| | - Daniel Huster
- Institute of Medical Physics and Biophysics
- University of Leipzig
- D-04107 Leipzig
- Germany
| | - Luís M. S. Loura
- Centro de Química de Coimbra
- P-3004-535 Coimbra
- Portugal
- Faculdade de Farmácia
- Universidade de Coimbra
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39
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Nierzwicki L, Wieczor M, Censi V, Baginski M, Calucci L, Samaritani S, Czub J, Forte C. Interaction of cisplatin and two potential antitumoral platinum(ii) complexes with a model lipid membrane: a combined NMR and MD study. Phys Chem Chem Phys 2015; 17:1458-68. [DOI: 10.1039/c4cp04360j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Multinuclear NMR and MD calculations highlighted the different interactions of cisplatin and two potential antitumoral Pt(ii) complexes with a model membrane.
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Affiliation(s)
- L. Nierzwicki
- Department of Physical Chemistry
- Gdansk University of Technology
- 80-233 Gdansk
- Poland
| | - M. Wieczor
- Department of Physical Chemistry
- Gdansk University of Technology
- 80-233 Gdansk
- Poland
| | - V. Censi
- Department of Chemistry and Industrial Chemistry
- University of Pisa
- 56126 Pisa
- Italy
| | - M. Baginski
- Department of Pharmaceutical Technology and Biochemistry
- Gdansk University of Technology
- 80-233 Gdansk
- Poland
| | - L. Calucci
- Institute of the Chemistry of Organometallic Compounds
- CNR
- 56124 Pisa
- Italy
| | - S. Samaritani
- Department of Chemistry and Industrial Chemistry
- University of Pisa
- 56126 Pisa
- Italy
| | - J. Czub
- Department of Physical Chemistry
- Gdansk University of Technology
- 80-233 Gdansk
- Poland
| | - C. Forte
- Institute of the Chemistry of Organometallic Compounds
- CNR
- 56124 Pisa
- Italy
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40
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Yasuda T, Kinoshita M, Murata M, Matsumori N. Detailed comparison of deuterium quadrupole profiles between sphingomyelin and phosphatidylcholine bilayers. Biophys J 2014; 106:631-8. [PMID: 24507603 DOI: 10.1016/j.bpj.2013.12.034] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/25/2013] [Accepted: 12/26/2013] [Indexed: 11/25/2022] Open
Abstract
Lipid rafts are microdomains rich in sphingomyelin (SM) and cholesterol (Chol). The essential question is why natural lipid rafts prefer SM rather than saturated diacyl glycerophosphocholine, although both form ordered membranes with Chol in model systems. Hence in this study, we synthesized site-specifically deuterated 1-palmitoyl-2-stearoyl-sn-glycero-3-phosphocholines that match the acyl chain length of stearoyl-SM (SSM), and compared their deuterium quadrupole coupling profiles in detail. The results suggest a deeper distribution of Chol in the SSM membranes, a lower entropic penalty upon accommodation of Chol in SSM membranes, and a higher thermal stability of acyl-chain orders in the SSM-Chol bilayers than in the 1-palmitoyl-2-stearoyl-sn-glycero-3-phosphocholine-Chol system at various Chol concentrations. The entropy effect and thermal stability should render SM a more preferred raft constituent than saturated diacyl glycerophosphocholine. Our data also demonstrate that the selective and comprehensive deuteration strategy is indispensable for accurate comparison of order profiles.
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Affiliation(s)
- Tomokazu Yasuda
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan; Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Toyonaka, Osaka, Japan
| | - Masanao Kinoshita
- Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Toyonaka, Osaka, Japan
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan; Japan Science and Technology Agency, ERATO, Lipid Active Structure Project, Toyonaka, Osaka, Japan
| | - Nobuaki Matsumori
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
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41
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Membrane properties of cholesterol analogs with an unbranched aliphatic side chain. Chem Phys Lipids 2014; 184:1-6. [PMID: 25173446 DOI: 10.1016/j.chemphyslip.2014.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/07/2014] [Accepted: 08/21/2014] [Indexed: 11/21/2022]
Abstract
The interactions between cholesterol and other membrane molecules determine important membrane properties. It was shown that even small changes in the molecular structure of cholesterol have a crucial influence on these interactions. We recently reported that in addition to alterations in the tetracyclic ring structure, the iso-branched side chain of cholesterol also has a significant impact on membrane properties (Scheidt et al., 2013). Here we used synthetic cholesterol analogs to investigate the influence of an unbranched aliphatic side chain of different length. The (2)H NMR order parameter of the phospholipid chains and therefore the molecular packing of the phospholipid molecules shows a significant dependence on the sterol's alkyl side chain length, while, membrane permeation studied by a dithionite ion permeation assay and lateral diffusion measured by (1)H MAS pulsed field gradient NMR are less influenced. To achieve the same molecular packing effect similar to that of an iso-branched aliphatic side chain, a longer unbranched side chain (n-dodecyl instead of n-octyl) at C17 of cholesterol is required. Obviously, sterols having a branched iso-alkyl chain with two terminal methyl groups exhibit altered cholesterol-phospholipid interactions compared to analogous molecules with a straight unbranched chain.
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42
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How well does cholesteryl hemisuccinate mimic cholesterol in saturated phospholipid bilayers? J Mol Model 2014; 20:2121. [DOI: 10.1007/s00894-014-2121-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 12/18/2013] [Indexed: 12/22/2022]
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43
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Poger D, Mark AE. The Relative Effect of Sterols and Hopanoids on Lipid Bilayers: When Comparable Is Not Identical. J Phys Chem B 2013; 117:16129-40. [DOI: 10.1021/jp409748d] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David Poger
- School
of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane QLD 4072, Australia
| | - Alan E. Mark
- School
of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane QLD 4072, Australia
- Institute
for Molecular Bioscience, The University of Queensland, Brisbane QLD 4072, Australia
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44
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Scheidt HA, Meyer T, Nikolaus J, Baek DJ, Haralampiev I, Thomas L, Bittman R, Müller P, Herrmann A, Huster D. Cholesterol's aliphatic side chain modulates membrane properties. Angew Chem Int Ed Engl 2013; 52:12848-51. [PMID: 24382636 PMCID: PMC4011182 DOI: 10.1002/anie.201306753] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Indexed: 11/06/2022]
Abstract
The influence of cholesterol's alkyl side chain on membrane properties was studied using a series of synthetic cholesterol derivatives without a side chain or with a branched side chain consisting of 5 to 14 carbon atoms. Cholesterol's side chain is crucial for all membrane properties investigated and therefore essential for the membrane properties of eukaryotic cells.
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Affiliation(s)
- Holger A. Scheidt
- Institute of Medical Physics and Biophysics, University of Leipzig,
Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Thomas Meyer
- Institute of Medical Physics and Biophysics, University of Leipzig,
Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Jörg Nikolaus
- Institute of Biology/Biophysics, Humboldt University Berlin,
Invalidenstr. 42, D-10115 Berlin, Germany
| | - Dong Jae Baek
- Department of Chemistry and Biochemistry, Queens College of CUNY,
Flushing, NY 11367-1597, USA
| | - Ivan Haralampiev
- Institute of Biology/Biophysics, Humboldt University Berlin,
Invalidenstr. 42, D-10115 Berlin, Germany
| | - Lars Thomas
- Institute of Medical Physics and Biophysics, University of Leipzig,
Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Robert Bittman
- Department of Chemistry and Biochemistry, Queens College of CUNY,
Flushing, NY 11367-1597, USA
| | - Peter Müller
- Institute of Biology/Biophysics, Humboldt University Berlin,
Invalidenstr. 42, D-10115 Berlin, Germany
| | - Andreas Herrmann
- Institute of Biology/Biophysics, Humboldt University Berlin,
Invalidenstr. 42, D-10115 Berlin, Germany
| | - Daniel Huster
- Institute of Medical Physics and Biophysics, University of
Leipzig, Härtelstr. 16-18, D-04107 Leipzig, Germany
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45
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Scheidt HA, Meyer T, Nikolaus J, Baek DJ, Haralampiev I, Thomas L, Bittman R, Müller P, Herrmann A, Huster D. Die aliphatische Seitenkette von Cholesterol bestimmt essenzielle Membraneigenschaften. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201306753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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46
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Gapsys V, de Groot BL, Briones R. Computational analysis of local membrane properties. J Comput Aided Mol Des 2013; 27:845-58. [PMID: 24150904 PMCID: PMC3882000 DOI: 10.1007/s10822-013-9684-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 10/07/2013] [Indexed: 11/29/2022]
Abstract
In the field of biomolecular simulations, dynamics of phospholipid membranes is of special interest. A number of proteins, including channels, transporters, receptors and short peptides are embedded in lipid bilayers and tightly interact with phospholipids. While the experimental measurements report on the spatial and/or temporal average membrane properties, simulation results are not restricted to the average properties. In the current study, we present a collection of methods for an efficient local membrane property calculation, comprising bilayer thickness, area per lipid, deuterium order parameters, Gaussian and mean curvature. The local membrane property calculation allows for a direct mapping of the membrane features, which subsequently can be used for further analysis and visualization of the processes of interest. The main features of the described methods are highlighted in a number of membrane systems, namely: a pure dimyristoyl-phosphatidyl-choline (DMPC) bilayer, a fusion peptide interacting with a membrane, voltage-dependent anion channel protein embedded in a DMPC bilayer, cholesterol enriched bilayer and a coarse grained simulation of a curved palmitoyl-oleoyl-phosphatidyl-choline lipid membrane. The local membrane property analysis proves to provide an intuitive and detailed view on the observables that are otherwise interpreted as averaged bilayer properties.
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Affiliation(s)
- Vytautas Gapsys
- Computational Biomolecular Dynamics Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany,
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47
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Domonkos I, Kis M, Gombos Z, Ughy B. Carotenoids, versatile components of oxygenic photosynthesis. Prog Lipid Res 2013; 52:539-61. [PMID: 23896007 DOI: 10.1016/j.plipres.2013.07.001] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 07/19/2013] [Accepted: 07/19/2013] [Indexed: 12/13/2022]
Abstract
Carotenoids (CARs) are a group of pigments that perform several important physiological functions in all kingdoms of living organisms. CARs serve as protective agents, which are essential structural components of photosynthetic complexes and membranes, and they play an important role in the light harvesting mechanism of photosynthesizing plants and cyanobacteria. The protection against reactive oxygen species, realized by quenching of singlet oxygen and the excited states of photosensitizing molecules, as well as by the scavenging of free radicals, is one of the main biological functions of CARs. X-ray crystallographic localization of CARs revealed that they are present at functionally and structurally important sites of both the PSI and PSII reaction centers. Characterization of a CAR-less cyanobacterial mutant revealed that while the absence of CARs prevents the formation of PSII complexes, it does not abolish the assembly and function of PSI. CAR molecules assist in the formation of protein subunits of the photosynthetic complexes by gluing together their protein components. In addition to their aforementioned indispensable functions, CARs have a substantial role in the formation and maintenance of proper cellular architecture, and potentially also in the protection of the translational machinery under stress conditions.
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Affiliation(s)
- Ildikó Domonkos
- Institute of Plant Biology, Biological Research Centre of Hungarian Academy of Sciences, P.O. Box 521, H-6701 Szeged, Hungary
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48
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Kett PJN, Casford MTL, Davies PB. Orientation of cholesterol in hybrid bilayer membranes calculated from the phases of methyl resonances in sum frequency generation spectra. J Chem Phys 2013; 138:225101. [DOI: 10.1063/1.4807854] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- P J N Kett
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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49
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Roux M, Sternin E, Bonnet V, Fajolles C, Djedaíni-Pilard F. Dynamic lipid lateral segregation driven by lauryl cyclodextrin interactions at the membrane surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:3677-3687. [PMID: 23409976 DOI: 10.1021/la304524a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Amphiphilic cyclodextrins, with a cholesterol anchor (βChol) or an aspartic acid moiety esterified by two lauryl acyl chains (βDLC), were designed to combine the inclusion ability of the cyclodextrin cavity with the carrier properties of model membranes. Their insertion in phosphatidylcholine bilayers induces a marked lateral phase separation into a pure lipid phase and a cyclodextrin-rich phase (LCD), organized as a 2D cyclodextrin network stabilized by intermolecular hydrogen bonds between the saccharide headgroups at the membrane surface (Roux, M.; Perly, B.; Djedaïni-Pilard, F. Self-Assemblies of Amphiphilic Cyclodextrins. Eur. Biophys. J.2007, 36, 861-867). We have replaced the dilauryl anchor by a single lauryl chain grafted onto a leucine residue, giving monolauryl-β-cyclodextrin (βMLC), which readily inserts into bilayers of chain-deuterated DMPC-d27. The removal of one lauryl acyl chain leads to a dynamic membrane insertion of this new cyclodextrin derivative, with significant lipid exchange on the deuterium NMR time scale between a loosely packed cyclodextrin-enriched phase (L'CD) and free lipid regions, yielding broadened two-component NMR spectra. Like the LCD phases, the cyclodextrin-enriched L'CD regions remain (partially) fluid below the DMPC-d27 main fluid-to-gel transition but do not undergo a clear transition toward a gel state, as observed at 14.5 °C in the LCD phase induced by the dilauryl derivative. Partially fluid lipids of the βMLC-induced L'CD phase coexist with pure lipids in the Pβ' gel phase with possible exchange between them until all of the lipids undergo a transition toward an Lβ' gel state at around 7 °C. Trimethylated monolauryl-β-cyclodextrins induce only an ordering of the lipid acyl chains just above the main transition, without any lateral phase separation. Similar chain ordering is also observed within the βMLC-induced L'CD phase as a consequence of the deep membrane insertion of the monolauryl nonmethylated cyclodextrin derivative.
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Affiliation(s)
- Michel Roux
- CEA/DSV/iBiTec-S, UMR CNRS 8221, SB2SM, F-91191 Gif sur Yvette Cedex, France
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50
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Ye W, Liebau J, Mäler L. New Membrane Mimetics with Galactolipids: Lipid Properties in Fast-Tumbling Bicelles. J Phys Chem B 2013; 117:1044-50. [DOI: 10.1021/jp311093p] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Weihua Ye
- Department
of Biochemistry and Biophysics, The Arrhenius
Laboratory, Stockholm University, 106 91
Stockholm, Sweden
| | - Jobst Liebau
- Department
of Biochemistry and Biophysics, The Arrhenius
Laboratory, Stockholm University, 106 91
Stockholm, Sweden
| | - Lena Mäler
- Department
of Biochemistry and Biophysics, The Arrhenius
Laboratory, Stockholm University, 106 91
Stockholm, Sweden
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