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Barrantes FJ. Fluorescence sensors for imaging membrane lipid domains and cholesterol. CURRENT TOPICS IN MEMBRANES 2021; 88:257-314. [PMID: 34862029 DOI: 10.1016/bs.ctm.2021.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Lipid membrane domains are supramolecular lateral heterogeneities of biological membranes. Of nanoscopic dimensions, they constitute specialized hubs used by the cell as transient signaling platforms for a great variety of biologically important mechanisms. Their property to form and dissolve in the bulk lipid bilayer endow them with the ability to engage in highly dynamic processes, and temporarily recruit subpopulations of membrane proteins in reduced nanometric compartments that can coalesce to form larger mesoscale assemblies. Cholesterol is an essential component of these lipid domains; its unique molecular structure is suitable for interacting intricately with crevices and cavities of transmembrane protein surfaces through its rough β face while "talking" to fatty acid acyl chains of glycerophospholipids and sphingolipids via its smooth α face. Progress in the field of membrane domains has been closely associated with innovative improvements in fluorescence microscopy and new fluorescence sensors. These advances enabled the exploration of the biophysical properties of lipids and their supramolecular platforms. Here I review the rationale behind the use of biosensors over the last few decades and their contributions towards elucidation of the in-plane and transbilayer topography of cholesterol-enriched lipid domains and their molecular constituents. The challenges introduced by super-resolution optical microscopy are discussed, as well as possible scenarios for future developments in the field, including virtual ("no staining") staining.
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Affiliation(s)
- Francisco J Barrantes
- Biomedical Research Institute (BIOMED), Catholic University of Argentina (UCA)-National Scientific and Technical Research Council (CONICET), Buenos Aires, Argentina.
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2
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Qin X, Yang X, Du L, Li M. Polarity-based fluorescence probes: properties and applications. RSC Med Chem 2021; 12:1826-1838. [PMID: 34825183 PMCID: PMC8597426 DOI: 10.1039/d1md00170a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 08/07/2021] [Indexed: 11/21/2022] Open
Abstract
Local polarity can affect the physical or chemical behaviors of surrounding molecules, especially in organisms. Cell polarity is the ultimate feedback of cellular status and regulation mechanisms. Hence, the abnormal alteration of polarity in organisms is closely linked with functional disorders and many diseases. It is incredibly significant to monitor and detect local polarity to explain the biological processes and diagnoses of some diseases. Because of their in vivo safe and real-time monitoring, several polarity-sensitive fluorophores and fluorescent probes have gradually emerged and been used in modern research. This review summarizes the fluorescence properties and applications of several representative polarity-sensitive fluorescent probes.
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Affiliation(s)
- Xiaojun Qin
- School of Pharmacy, Guangxi Medical University Nanning Guangxi 530021 China
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University Jinan Shandong 250012 China
| | - Xingye Yang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University Jinan Shandong 250012 China
| | - Lupei Du
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University Jinan Shandong 250012 China
| | - Minyong Li
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Cheeloo College of Medicine, Shandong University Jinan Shandong 250012 China
- State Key Laboratory of Microbial Technology, Shandong University Jinan Shandong 250100 China
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3
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Fabiani C, Antollini SS. Alzheimer's Disease as a Membrane Disorder: Spatial Cross-Talk Among Beta-Amyloid Peptides, Nicotinic Acetylcholine Receptors and Lipid Rafts. Front Cell Neurosci 2019; 13:309. [PMID: 31379503 PMCID: PMC6657435 DOI: 10.3389/fncel.2019.00309] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/25/2019] [Indexed: 12/17/2022] Open
Abstract
Biological membranes show lateral and transverse asymmetric lipid distribution. Cholesterol (Chol) localizes in both hemilayers, but in the external one it is mostly condensed in lipid-ordered microdomains (raft domains), together with saturated phosphatidyl lipids and sphingolipids (including sphingomyelin and glycosphingolipids). Membrane asymmetries induce special membrane biophysical properties and behave as signals for several physiological and/or pathological processes. Alzheimer’s disease (AD) is associated with a perturbation in different membrane properties. Amyloid-β (Aβ) plaques and neurofibrillary tangles of tau protein together with neuroinflammation and neurodegeneration are the most characteristic cellular changes observed in this disease. The extracellular presence of Aβ peptides forming senile plaques, together with soluble oligomeric species of Aβ, are considered the major cause of the synaptic dysfunction of AD. The association between Aβ peptide and membrane lipids has been extensively studied. It has been postulated that Chol content and Chol distribution condition Aβ production and posterior accumulation in membranes and, hence, cell dysfunction. Several lines of evidence suggest that Aβ partitions in the cell membrane accumulate mostly in raft domains, the site where the cleavage of the precursor AβPP by β- and γ- secretase is also thought to occur. The main consequence of the pathogenesis of AD is the disruption of the cholinergic pathways in the cerebral cortex and in the basal forebrain. In parallel, the nicotinic acetylcholine receptor has been extensively linked to membrane properties. Since its transmembrane domain exhibits extensive contacts with the surrounding lipids, the acetylcholine receptor function is conditioned by its lipid microenvironment. The nicotinic acetylcholine receptor is present in high-density clusters in the cell membrane where it localizes mainly in lipid-ordered domains. Perturbations of sphingomyelin or cholesterol composition alter acetylcholine receptor location. Therefore, Aβ processing, Aβ partitioning, and acetylcholine receptor location and function can be manipulated by changes in membrane lipid biophysics. Understanding these mechanisms should provide insights into new therapeutic strategies for prevention and/or treatment of AD. Here, we discuss the implications of lipid-protein interactions at the cell membrane level in AD.
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Affiliation(s)
- Camila Fabiani
- Instituto de Investigaciones Bioquímicas de Bahía Blanca CONICET-UNS, Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - Silvia S Antollini
- Instituto de Investigaciones Bioquímicas de Bahía Blanca CONICET-UNS, Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
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4
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Suga K, Akizaki K, Umakoshi H. Quantitative Monitoring of Microphase Separation Behaviors in Cationic Liposomes Using HHC, DPH, and Laurdan: Estimation of the Local Electrostatic Potentials in Microdomains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:3630-3636. [PMID: 27022833 DOI: 10.1021/acs.langmuir.5b04682] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Microphase separation behaviors of cationic liposomes have been investigated using a pH-sensitive fluorescent probe with 4-heptadecyl-7-hydroxycoumarin (HHC), 1,6-diphenyl-1,3,5-hexatriene, and 6-lauroyl-2-dimethylaminonaphthalene, and to estimate localized electrostatic potentials. Shifts of the apparent pKa values of HHC were observed in cationic liposomes in proportion to the amount of cationic lipids. Two pKa values were obtained with 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/3β-[N(N',N'-dimethylaminoethane)-carbamoyl] cholesterol hydrochloride (DC-Ch) liposomes, while only one pKa value was generated with either DOPC/1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) or DOPC/dimethyldioctadecylammonium-bromide (DODAB) liposomes. The physicochemical membrane property analyses, focusing on membrane fluidity and membrane polarity, revealed heterogeneity among DOPC/DC-Ch liposomes. By analyzing the pH titration curves using sigmoidal fitting, the localized electrostatic potentials were estimated. For DOPC/DOTAP = (7/3), the membrane was in the liquid-disordered phase and the density of cationic molecules was 0.41 cation/nm(2). For DOPC/DC-Ch = (7/3), the membrane was heterogeneous and the densities of cationic molecules in liquid-disordered and liquid-ordered phases were 0.25 and 1.24 cation/nm(2), respectively. We thereby conclude that the DC-Ch molecules can form nanodomains when these molecules are concentrated to 59%.
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Affiliation(s)
- Keishi Suga
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Kei Akizaki
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Umakoshi
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , 1-3 Machikaneyamacho, Toyonaka, Osaka 560-8531, Japan
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Tang J, Xie D, Yin HY, Jing J, Zhang JL. Cationic sulfonium functionalization renders Znsalens with high fluorescence, good water solubility and tunable cell-permeability. Org Biomol Chem 2016; 14:3360-8. [DOI: 10.1039/c6ob00249h] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Introducing cationic sulfonium to the Znsalens skeleton circumvents aggregation arising from intermolecular Zn⋯O interactions (found between Zn and the phenoxyl group of another Znsalen molecule).
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Affiliation(s)
- Juan Tang
- Beijing National Laboratory for Molecular Sciences
- State Key Laboratory of Rare Earth Materials Chemistry and Applications
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
| | - Da Xie
- Beijing National Laboratory for Molecular Sciences
- State Key Laboratory of Rare Earth Materials Chemistry and Applications
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
| | - Hao-Yan Yin
- Beijing National Laboratory for Molecular Sciences
- State Key Laboratory of Rare Earth Materials Chemistry and Applications
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
| | - Jing Jing
- School of Chemistry
- Beijing Institute of Technology
- Beijing 100081
- P.R. China
| | - Jun-Long Zhang
- Beijing National Laboratory for Molecular Sciences
- State Key Laboratory of Rare Earth Materials Chemistry and Applications
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
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6
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Fraňová MD, Repáková J, Holopainen JM, Vattulainen I. How to link pyrene to its host lipid to minimize the extent of membrane perturbations and to optimize pyrene dimer formation. Chem Phys Lipids 2014; 177:19-25. [DOI: 10.1016/j.chemphyslip.2013.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 10/08/2013] [Accepted: 10/11/2013] [Indexed: 11/30/2022]
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7
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Vazdar M, Wernersson E, Khabiri M, Cwiklik L, Jurkiewicz P, Hof M, Mann E, Kolusheva S, Jelinek R, Jungwirth P. Aggregation of Oligoarginines at Phospholipid Membranes: Molecular Dynamics Simulations, Time-Dependent Fluorescence Shift, and Biomimetic Colorimetric Assays. J Phys Chem B 2013; 117:11530-40. [DOI: 10.1021/jp405451e] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Mario Vazdar
- Division
of Organic Chemistry and Biochemistry, Rudjer Bošković Institute, P.O.B.
180, HR-10002 Zagreb, Croatia
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Erik Wernersson
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Morteza Khabiri
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Lukasz Cwiklik
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- J. Heyrovský
Institute of Physical Chemistry, Academy of Sciences of the Czech Republic v.v.i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Piotr Jurkiewicz
- J. Heyrovský
Institute of Physical Chemistry, Academy of Sciences of the Czech Republic v.v.i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Martin Hof
- J. Heyrovský
Institute of Physical Chemistry, Academy of Sciences of the Czech Republic v.v.i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Ella Mann
- Department
of Chemistry and the Ilse Katz Institute for Nanoscale Science and
Technology, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Sofiya Kolusheva
- Department
of Chemistry and the Ilse Katz Institute for Nanoscale Science and
Technology, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Raz Jelinek
- Department
of Chemistry and the Ilse Katz Institute for Nanoscale Science and
Technology, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Pavel Jungwirth
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- Department
of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
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8
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Barucha-Kraszewska J, Kraszewski S, Ramseyer C. Will C-Laurdan dethrone Laurdan in fluorescent solvent relaxation techniques for lipid membrane studies? LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:1174-82. [PMID: 23311388 DOI: 10.1021/la304235r] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Development of fluorescence methods involves the necessity of understanding the fluorescent probes behavior in their ground and excited states. In the case of biological membranes, the position of the dyes in the lipid bilayer and their response after excitation are necessary parameters to correctly analyze the experiments. In the present work, we focus on two fluorescent markers, Laurdan (6-lauroyl-2-(N,N-dimethylamino)naphthalene) and its derivative C-Laurdan (6-dodecanoyl-2-[N-methyl-N-(carboxymethyl)amino]naphthalene), recently proposed for lipid raft visualization [Kim, H. M.; et al. ChemBioChem 2007, 8, 553]. C-Laurdan, by the presence of an additional carboxyl group, has an advantage over Laurdan since it has a higher sensitivity to the membrane polarity at the lipid headgroup region and a higher water solubility. This theoretical study, based on quantum mechanical (QM) and molecular dynamics (MD) simulations in a fully hydrated lipid membrane model, compare the equilibrium and dynamic properties of both probes taking into account their fluorescence lifetimes. C-Laurdan is found to be more stable than Laurdan in the headgroup region of the membrane and also much more aligned with the lipids. This study suggests that, besides the lipid raft imaging, the C-Laurdan marker can considerably extend the capabilities of fluorescent solvent relaxation method.
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Affiliation(s)
- Justyna Barucha-Kraszewska
- Laboratoire de Nanomédecine, Imagerie et Thérapeutique, EA4662, Université de Franche-Comté, Centre Hospitalier Universitaire de Besançon, 16 Route de Gray, 25000 Besançon, France.
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9
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Przybyło M, Olzyńska A, Han S, Ozyhar A, Langner M. A fluorescence method for determining transport of charged compounds across lipid bilayer. Biophys Chem 2007; 129:120-5. [PMID: 17566633 DOI: 10.1016/j.bpc.2007.05.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 05/15/2007] [Accepted: 05/15/2007] [Indexed: 11/26/2022]
Abstract
There is a constant need for simple, economical and time-efficient methods which allow evaluating a compound's ability to penetrate the biological membrane, one of the key parameters needed to characterize biologically active compounds. In the paper we propose a new method of permeability determination. Instead of detecting the compound's concentration directly, we employ an approach in which the membrane interface is labeled with a fluorescein lipid probe; the probe is sensitive to the presence of charged compounds. The fluorescence intensity changes of the dye permanently attached to both sides of a model lipid bilayer are measured. Specifically, the time course of the fluorescence intensity changes following a rapid induction of a non-equilibrium state of the sample allows the evaluation of the membrane permeability for the compound. The method was validated by the determination of the phenyltin compound's transport through the model phosphatidylcholine unilamellar liposome bilayer.
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Affiliation(s)
- Magda Przybyło
- Wrocław University of Technology, Department of Biomedical Engineering and Measurements, Wyb. Wyspiańskiego 27, 50-370 Wrocław, Poland.
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10
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Jurkiewicz P, Olzyńska A, Langner M, Hof M. Headgroup hydration and mobility of DOTAP/DOPC bilayers: a fluorescence solvent relaxation study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:8741-9. [PMID: 17014112 DOI: 10.1021/la061597k] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The biophysical properties of liposome surfaces are critical for interactions between lipid aggregates and macromolecules. Liposomes formed from cationic lipids, commonly used to deliver genes into cells in vitro and in vivo, are an example of such a system. We apply the fluorescence solvent relaxation technique to study the structure and dynamics of fully hydrated liquid crystalline lipid bilayers composed of mixtures of cationic dioleoyltrimethylammoniumpropane (DOTAP) and neutral dioleoylphosphatidylcholine (DOPC). Using three different naphthalene derivatives as fluorescent dyes (Patman, Laurdan and Prodan) allowed different parts of the headgroup region to be probed. Wavelength-dependent parallax quenching measurements resulted in the precise determination of Laurdan and Patman locations within the DOPC bilayer. Acrylamide quenching experiments were used to examine DOTAP-induced dye relocalization. The nonmonotonic dependence of dipolar relaxation kinetics (occurring exclusively on the nanosecond time scale) on DOTAP content in the membrane was found to exhibit a maximum mean solvent relaxation time at 30 mol % of DOTAP. Up to 30 mol %, addition of DOTAP does not influence the amount of bound water at the level of the sn(1) carbonyls, but leads to an increased packing of phospholipid headgroups. Above this concentration, elevated lipid bilayer water penetration was observed.
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Affiliation(s)
- Piotr Jurkiewicz
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-18223 Prague 8, Czech Republic
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11
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Ioffe VM, Gorbenko GP, Domanov YA, Tatarets AL, Patsenker LD, Terpetsching EA, Dyubko TS. A New Fluorescent Squaraine Probe for the Measurement of Membrane Polarity. J Fluoresc 2006; 16:47-52. [PMID: 16397827 DOI: 10.1007/s10895-005-0018-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2005] [Accepted: 09/27/2005] [Indexed: 10/25/2022]
Abstract
The present study was undertaken to evaluate the sensitivity of newly synthesized squaraine dye 1 to the changes in lipid bilayer physical properties and compared it with the well-known dye 2. Partitioning of the dye 1 into lipid bilayer was found to be followed by significant increase of its fluorescence intensity and red-shift of emission maximum, while intensity of the dye 2 fluorescence increased only slightly on going from aqueous to lipidic environment. This suggests that dye 1 is more sensitive to the changes in membrane properties as compared to dye 2. Partition coefficients of the dye 1 have been determined for the model membranes composed of zwitterionic phospholipid phosphatidylcholine (PC) and its mixtures with positively charged detergent cetyltrimethylammonium bromide (CTAB), anionic phospholipid cardiolipin (CL), and sterol (Chol). The spectral responses of the dye 1 in different liposome media proved to correlate with the increase of bilayer polarity induced by Chol and CL or its decrease caused by CTAB. It was concluded that dye 1 can be used as fluorescent probe for examining membrane-related processes.
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Affiliation(s)
- Valeriya M Ioffe
- Department of Biological and Medical Physics, V.N. Karazin Kharkov National University, Kharkov, Ukraine.
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12
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Sýkora J, Jurkiewicz P, Epand RM, Kraayenhof R, Langner M, Hof M. Influence of the curvature on the water structure in the headgroup region of phospholipid bilayer studied by the solvent relaxation technique. Chem Phys Lipids 2005; 135:213-21. [PMID: 15921979 DOI: 10.1016/j.chemphyslip.2005.03.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2005] [Revised: 03/03/2005] [Accepted: 03/07/2005] [Indexed: 11/26/2022]
Abstract
Solvent relaxation (SR) in 1,2-dioleoyl-palmitoyl-sn-glycero-3-phosphocholine (DOPC) unilamellar vesicles of different size was probed by 6-hexadecanoyl-2-(((2-(trimethylammonium)ethyl)methyl)amino)naphthalene chloride (Patman), 6-propionyl-2-dimethylaminonaphthalene (Prodan) and 4-[(n-dodecylthio)methyl]-7-(N,N-dimethylamino)-coumarin (DTMAC). Patman probes the amount and mobility of the bound water molecules located at the carbonyl region of the bilayer. Membrane curvature significantly accelerates the solvent relaxation process, but does not influence the total Stokes shift, showing that membrane curvature increases the mobility, without affecting the amount of water molecules present in the headgroup region. This pattern was also verified for other phosphatidylcholines. Prodan is located in the phosphate region of the bilayer and probes a more polar, mobile and heterogeneous environment than Patman. The influence of membrane curvature on SR probed by Prodan is similar, however, less pronounced compared to Patman. DTMAC (first time used in SR) shows a broad distribution of locations along the z-axis. A substantial amount of the coumarin chromophores face bulk water. No effect of curvature on SR probed by DTMAC is detectable.
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Affiliation(s)
- Jan Sýkora
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-18223 Prague 8, Czech Republic
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13
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Repáková J, Holopainen JM, Morrow MR, McDonald MC, Capková P, Vattulainen I. Influence of DPH on the structure and dynamics of a DPPC bilayer. Biophys J 2005; 88:3398-410. [PMID: 15722435 PMCID: PMC1305487 DOI: 10.1529/biophysj.104.055533] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Accepted: 02/02/2005] [Indexed: 12/24/2022] Open
Abstract
We have conducted extensive molecular dynamics (MD) simulations together with differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR) experiments to quantify the influence of free 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescent probes on the structure and dynamics of a dipalmitoylphosphatidylcholine bilayer. Atomistic MD simulations show that in the membrane-water interface the influence of DPH is minor, whereas in the acyl-chain region DPH gives rise to major perturbations. In the latter case, DPH is found to influence a wide range of membrane properties, such as the packing and ordering of hydrocarbon tails and the lateral diffusion of lipid molecules. The effects are prominent but of local nature, i.e., the changes observed in the properties of lipid molecules are significant in the vicinity of DPH, but reduce rapidly as the distance from the probe increases. Long-range perturbations due to DPH are hence not expected. Detailed DSC and (2)H NMR measurements support this view. DSC shows only subtle perturbation to the cooperative behavior of the membrane system in the presence of DPH, and (2)H NMR shows that DPH gives rise to a slight increase in the lipid chain order, in agreement with MD simulations. Potential effects of other probes such as pyrene are briefly discussed.
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Affiliation(s)
- Jarmila Repáková
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
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14
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Tomohiro T, Ogawa Y, Okuno H, Kodaka M. Synthesis and spectroscopic analysis of chromophoric lipids inducing pH-dependent liposome fusion. J Am Chem Soc 2004; 125:14733-40. [PMID: 14640648 DOI: 10.1021/ja037796x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We design novel chromophoric amphiphiles 6a-c, which lead to pH-dependent membrane fusion of egg phosphatidylcholine (eggPC) liposome containing them. Lipids 6a-c comprise double alkyl chains, a single chain with a 2-nitrophenol group as a pH trigger, and dipeptide (Asp-Asp) between them. The pKa values of 2-nitrophenol groups of 6a-c in liposome are larger than that of hydrophilic compound 9 in an aqueous solution. Absorption spectra indicate that the fields around 2-nitrophenol of 6a-c situated in liposome membranes are more hydrophobic than that of 9 in an aqueous solution, whereas the environments around deprotonated 2-nitrophenolate of 6b and 6c are not so hydrophobic as that of 6a. This means that protonated 2-nitrophenol groups of 6a-c are embedded in bilayer membranes. Deprotonated 2-nitrophenol groups of 6b and 6c must be located in less hydrophobic circumstances, while that of 6a is still embedded in bilayer membranes because of its larger hydrophobicity. Absorption spectra and (1)H NMR spectra respectively suggest that protonated 2-nitrophenol groups of 6a and those of 6c might take face-to-face associations in bilayer membranes.
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Affiliation(s)
- Takenori Tomohiro
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
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15
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Singh Y, Gulyani A, Bhattacharya S. A new ratiometric fluorescence probe as strong sensor of surface charge of lipid vesicles and micelles. FEBS Lett 2003; 541:132-6. [PMID: 12706833 DOI: 10.1016/s0014-5793(03)00314-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We report on the ability of a new fluorescent probe, 4-(2-pyren-1-yl-vinyl) pyridine, 1, to respond to micelles and phospholipid vesicles of different surface charge. The probe gets incorporated into micellar and membranous assemblies and shows a large red-shift in the fluorescence emission maxima especially when the surface charge of the organized media is anionic. The effect on the photo-excitation of the probe is very clear and pronounced as it can be easily visualized. The sample color upon photo-excitation changes from blue to orange/red once the probe experiences negatively charged vesicular or micellar surfaces. These results make the probe molecule useful as a reporter for sensing electrostatic environment in biological membranes and related organized assemblies.
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Affiliation(s)
- Yashveer Singh
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, India
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16
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Abstract
Aqueous dispersions of the anionic phospholipid dimyristoyl phosphatidylglycerol (DMPG), around 100 mM ionic strength, are known to exhibit a thermal behavior similar to that of the largely studied lipid dimyristoyl phosphatidylcholine (DMPC), which undergoes a gel to liquid crystalline phase transition at 23 degrees C, well characterized by differential scanning calorimetry (DSC), and other methods. However, at low ionic strength, DMPG has been shown to present a large gel-fluid transition region, ranging from 18 to 35 degrees C. This intermediate phase is optically transparent and characterized by a continuous change in membrane packing. Structural properties of the DMPG gel-fluid transition region will be discussed, based on results obtained by several techniques: electron spin resonance (ESR) of spin labels at the membrane surface and intercalated at different depths in the bilayer; light scattering; DSC; small angle X-ray scattering (SAXS); and fluorescence spectroscopy of probes in the bilayer.
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Affiliation(s)
- M Teresa Lamy-Freund
- Instituto de Física, Universidade de São Paulo, CP 66 318, CEP 05315-970, São Paulo, SP, Brazil.
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Drobnies AE, Davies SMA, Kraayenhof R, Epand RF, Epand RM, Cornell RB. CTP:phosphocholine cytidylyltransferase and protein kinase C recognize different physical features of membranes: differential responses to an oxidized phosphatidylcholine. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1564:82-90. [PMID: 12100999 DOI: 10.1016/s0005-2736(02)00404-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Protein kinase C (PKC) and CTP:phosphocholine cytidylyltransferase (CT) are two examples of enzymes that are regulated by reversible binding to membranes, and this binding is influenced by membrane physical properties. CT activation by oxidized phosphatidylcholines was recently demonstrated and was linked to the acyl chain disordering effect of the oxidized species (Biochemistry 38, 15606). In this paper, we compare the responses of PKC and CT to an oxidized PC, and investigate the physical properties of lipid bilayers that modulate the activity of these enzymes. We show that 1-palmitoyl, 2-(11,15 dihydroxy) eicosatrienoyl PC (diOH-PAPC) caused less of an increase in the temperature of the lamellar to hexagonal II transition (T(H)) of an unsaturated PE, compared to its parent, PAPC. Using a polarity-sensitive interfacial probe, we also found evidence to suggest that this oxidized PC increases interfacial packing pressure. We found that whereas diOH-PAPC activates CT, it inhibits PKC relative to the parent PAPC. The activities of both CT and PKC are known to increase in the presence of non-lamellar forming lipids. The greater activating effect of diOH-PAPC compared with PAPC, is consistent with a stimulation of the activity of CT by negative curvature strain. However, this is not the case with PKC, for which we suggest that surface packing pressure is of prime importance.
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Affiliation(s)
- Adrienne E Drobnies
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
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18
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Abstract
Charged lipids constitute a substantial fraction of all membrane lipids. Their charges vary in quantity and distribution within their headgroup regions. In long range interactions, their charges' value and electrostatic potential in the vicinity of the membrane surface can be approximated by the Guy-Chapman theory. This theory treats the interface as a charged structureless plain surrounded by uniform environments. However, if one considers intermolecular interactions, such assumptions need to be revised. The interface is in reality a thick region containing the residual charges of lipid headgroups. Their arrangement depends on the type of lipid present in the membrane. The variety of lipids and their biological functions suggests that charge distribution determines the extent and type of interaction with surface associated molecules. Numerous examples show that protein behavior at the lipid bilayer surface is determined by the type of lipid present, indicating protein specificity towards certain surface locations and local properties (determined by lipid composition) of a particular type. Such specificity is achieved by a combination of electrostatic, hydrophobic and enthropic effects. Comparing lipid biological activity, it can be stated that residual charge distribution is one of the factors of intermolecular recognition leading to the specific interaction of lipid molecules and selected proteins in various processes, particularly those involved with signal transduction pathways. Such specificity enables a variety of processes occurring simultaneously on the same membrane surface to function without cross-reaction interference.
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Affiliation(s)
- M Langner
- Department of Physics and Biophysics, Agricultural University, Wrocław, Poland.
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19
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Abstract
The polarity of the interface between a lipid bilayer membrane and bulk water is an important physical parameter of the membrane. It is likely that several membrane-dependent biological functions are modulated by this property. However, interfacial polarity can be difficult to define because of an imprecise knowledge of the molecular nature of the interface. Nevertheless, attempts have been made to measure this quantity with the use of fluorescent probes which are sensitive to the solvent polarity. Often, however, other factors, such as the rate of solvent relaxation must be known in order to interpret the fluorescent properties in terms of the dielectric constant. In addition, the spatial orientation and location of the fluorophore are often not known precisely. Nevertheless, there have been successful efforts to gain a more accurate knowledge of this aspect of membrane physical properties and its relationship to biological phenomena is discussed.
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Affiliation(s)
- R M Epand
- Department of Biochemistry, McMaster University Health Sciences Centre, Hamilton, Ont., Canada.
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20
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Riske KA, Nascimento OR, Peric M, Bales BL, Lamy-Freund MT. Probing DMPG vesicle surface with a cationic aqueous soluble spin label. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1418:133-46. [PMID: 10209218 DOI: 10.1016/s0005-2736(99)00019-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A small, highly aqueous soluble, deuterated, cationic spin label, 4-trimethylammonium-2,2,6,6-tetramethylpiperidine-d17-1-oxyl iodide (dCAT1), was used to directly monitor the negatively charged DMPG vesicle surface in order to test a recent suggestion (Riske et al., Chem. Phys. Lipids, 89 (1997) 31-44) that alterations in the surface potential accompanied apparent phase transitions observed by light scattering. The temperature dependence of the label partition between the lipid surface and the aqueous medium indicated an increase in the surface potential at the gel to liquid-crystal transition, supporting the previous suggestion. Results at the phase transition occurring at a higher temperature were less definitive. Although some change in the dCAT1 ESR spectra was observed, the interpretation of the phenomena is still rather unclear. DMPG surface potentials were estimated from the dCAT1 partition ratios (surface label moles/total label moles), using a simple two-sites model, where the electrostatic potential is zero everywhere but at the vesicle surface, and the interaction between the spin label and the membrane surface is chiefly electrostatic. The Gouy-Chapman-Stern model predicts surface potentials similar to those observed, although the measured decrease in the surface potential with ionic strength is somewhat steeper than that predicted by the model.
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Affiliation(s)
- K A Riske
- Instituto de Física, Universidade de São Paulo, CP 66318, CEP 05315-970, São Paulo, SP, Brazil
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21
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Holopainen JM, Lehtonen JY, Kinnunen PK. Evidence for the extended phospholipid conformation in membrane fusion and hemifusion. Biophys J 1999; 76:2111-20. [PMID: 10096906 PMCID: PMC1300184 DOI: 10.1016/s0006-3495(99)77367-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Molecular-level mechanisms of fusion and hemifusion of large unilamellar dioleoyl phosphatidic acid/phosphocholine (DOPA/DOPC, 1:1 molar ratio) vesicles induced by millimolar Ca2+ and Mg2+, respectively, were investigated using fluorescence spectroscopy. In keeping with reduction of membrane free volume Vf, both divalent cations increased the emission polarization for 1,6-diphenyl-1,3, 5-hexatriene (DPH). An important finding was a decrease in excimer/monomer emission intensity ratio (Ie/Im) for the intramolecular excimer-forming probe 1, 2-bis[(pyren-1-)yl]decanoyl-sn-glycero-3-phosphocholine (bis-PDPC) in the course of fusion and hemifusion. Comparison with another intramolecular excimer-forming probe, namely, 1-[(pyren-1)-yl]decanoyl-2-[(pyren-1)-yl]tetradecanoyl-sn-gl ycero-3-p hosphocholine (PDPTPC), allowed us to exclude changes in acyl chain alignment to be causing the decrement in Ie/Im. As a decrease in Vf should increase Ie/Im for bis-PDPC and because contact site between adhering liposomes was required we conclude the most feasible explanation to be the adoption of the extended conformation (P.K.J., Chem. Phys. Lipids 63:251-258) by bis-PDPC. In this conformation the two acyl chains are splaying so as to become embedded in the opposing leaflets of the two adhered bilayers, with the headgroup remaining between the adjacent surfaces. Our data provide evidence for a novel mechanism of fusion of the lipid bilayers.
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Affiliation(s)
- J M Holopainen
- Biomembrane Research Group, Department of Medical Chemistry, Institute of Biomedicine, University of Helsinki, FIN-00014 Helsinki, Finland
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22
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Abstract
Non-lamellar-forming lipids play an important role in determining the physical properties of membranes. They affect the activity of membrane proteins and peptides. In addition, peptides which lyse membranes as well as those which promote membrane fusion facilitate the formation of non-lamellar phases, either micelles, cubic or hexagonal phases. The relationship of these diverse effects on membrane curvature is discussed in relation to the function of certain peptides and proteins. Specific examples of ionophoric peptides, cytotoxic peptides and viral fusion peptides are given. In addition, we compare the modulation of the rate of photoisomerisation of an integral membrane protein, rhodopsin, by non-lamellar-forming lipids with the effects of these lipids on an amphitropic protein, protein kinase C. Among these diverse systems it is frequently observed that the modulation of biological activity can be described in terms of the effect of the peptide or protein on the relative stability of lamellar and non-lamellar structures.
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Affiliation(s)
- R M Epand
- Department of Biochemistry, McMaster University Health Sciences Centre, Hamilton, Ont. L8N 3Z5, Canada.
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Giorgione JR, Kraayenhof R, Epand RM. Interfacial membrane properties modulate protein kinase C activation: role of the position of acyl chain unsaturation. Biochemistry 1998; 37:10956-60. [PMID: 9692988 DOI: 10.1021/bi980185a] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We studied the effects of the addition of a series of 1, 2-dioctadecenoyl-sn-glycerol-3-phosphoethanolamines to vesicles composed of 1-palmitoyl-2-oleoylphosphatidylserine and 1-palmitoyl-2-oleoylphosphatidylcholine on the activity and membrane binding of protein kinase C (PKC). The three phosphatidylethanolamines (PEs) were dipetroselinoyl-PE, dioleoyl-PE, and divaccenoyl-PE, which have double bonds in positions 6, 9, and 11, respectively. These lipids represent a group of structurally homologous compounds whose physical properties have been compared. We also used a fluorescent probe, 4-[(n-dodecylthio)methyl]-7-(N, N-dimethylamino)coumarin to measure the relative interfacial polarities of LUVs containing each of the three PEs. We find dipetroselinoyl-PE allows the least access of the fluorescent probe to the membrane. This is also the lipid that shows the lowest activation of PKC. The activity of PKC was found to correlate best with the interfacial properties of the three PEs rather than with the curvature energy of the membrane. The results show the sensitivity of the activity of PKC to small changes in lipid structure.
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Affiliation(s)
- J R Giorgione
- Department of Biochemistry, McMaster University Health Sciences Centre, Hamilton, Ontario, Canada
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