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Geng Y, Cao Y, Li Y, Zhao Q, Liu D, Fan G, Tian S. A Deeper Insight into the Interfacial Behavior and Structural Properties of Mixed DPPC/POPC Monolayers: Implications for Respiratory Health. MEMBRANES 2022; 13:33. [PMID: 36676840 PMCID: PMC9864691 DOI: 10.3390/membranes13010033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/21/2022] [Accepted: 12/26/2022] [Indexed: 06/17/2023]
Abstract
1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1-palmitoyl-2-oleyl-sn-glycerol-3-phosphorcholine (POPC) are important components in pulmonary surfactants (PSs), of which the relative content is related to lung compliance. Herein, the phase behavior and thermodynamic structure of mixed DPPC/POPC monolayers were studied to elucidate the intermolecular interaction between DPPC and POPC molecules. Surface pressure-molecular area isotherms demonstrated that POPC significantly affected the phase behavior of the lipid domain structure as a function of its concentration. The compression modulus of the mixed monolayers reduced with the increase in POPC proportion, which can be attributed to the intermolecular repulsion between DPPC and POPC. Brewster angle microscopy analysis showed that the ordered structure of the monolayers trended toward fluidization in the presence of POPC. Raman spectroscopy results revealed that the change in C-C skeleton stretching vibration was the main cause of the decrease in the monolayer packing density. These findings provide new insights into the role of different phospholipid components in the function of PS film at a molecular level, which can help us to understand the synergy effects of the proportional relationship between DPPC and POPC on the formation and progression of lung disease and provide some references for the synthesis of lung surfactants.
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Affiliation(s)
- Yingxue Geng
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
- Faculty of Civil and Hydraulic Engineering, Xichang University, Xichang 615013, China
| | - Yan Cao
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yingjie Li
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Qun Zhao
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Dan Liu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Ge Fan
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Senlin Tian
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
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Bartucci R, Aloi E. Librational Dynamics of Spin-Labeled Membranes at Cryogenic Temperatures From Echo-Detected ED-EPR Spectra. Front Mol Biosci 2022; 9:923794. [PMID: 35847982 PMCID: PMC9277068 DOI: 10.3389/fmolb.2022.923794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 05/19/2022] [Indexed: 11/13/2022] Open
Abstract
Methods of electron spin echo of pulse electron paramagnetic resonance (EPR) spectroscopy are increasingly employed to investigate biophysical properties of nitroxide-labeled biosystems at cryogenic temperatures. Two-pulse echo-detected ED-spectra have proven to be valuable tools to describe the librational dynamics in the low-temperature phases of both lipids and proteins in membranes. The motional parameter, α2τC, given by the product of the mean-square angular amplitude, α2, and the rotational correlation time, τC, of the motion, is readily determined from the nitroxide ED-spectra as well as from the W-relaxation rate curves. An independent evaluation of α2 is obtained from the motionally averaged 14N-hyperfine splitting separation in the continuous wave cw-EPR spectra. Finally, the rotational correlation time τC can be estimated by combining ED- and cw-EPR data. In this mini-review, results on the librational dynamics in model and natural membranes are illustrated.
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Affiliation(s)
- Rosa Bartucci
- Department of Chemistry and Chemical Technologies, University of Calabria, Rende (CS), Italy
- *Correspondence: Rosa Bartucci,
| | - Erika Aloi
- Molecular Biophysics Laboratory, Department of Physics, University of Calabria, Rende (CS), Italy
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Low-temperature librations and dynamical transition in proteins at differing hydration levels. Biomol Concepts 2022; 13:81-88. [DOI: 10.1515/bmc-2022-0007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 02/14/2022] [Indexed: 11/15/2022] Open
Abstract
Abstract
Hydration of water affects the dynamics and in turn the activity of biomacromolecules. We investigated the dependence of the librational oscillations and the dynamical transition on the hydrating conditions of two globular proteins with different structure and size, namely β-lactoglobulin (βLG) and human serum albumin (HSA), by spin-label electron paramagnetic resonance (EPR) in the temperature range of 120–270 K. The proteins were spin-labeled with 5-maleimide spin-label on free cysteins and prepared in the lyophilized state, at low (h = 0.12) and full (h = 2) hydration levels in buffer. The angular amplitudes of librations are small and almost temperature independent for both lyophilized proteins. Therefore, in these samples, the librational dynamics is restricted and the dynamical transition is absent. In the small and compact beta-structured βLG, the angular librational amplitudes increase with temperature and hydrating conditions, whereas hydration-independent librational oscillations whose amplitudes rise with temperature are recorded in the large and flexible alpha-structured HSA. Both βLG and HSA at low and fully hydration levels undergo the dynamical transition at about 230 K. The overall results indicate that protein librational dynamics is activated at the low hydration level h = 0.12 and highlight biophysical properties that are common to other biosamples at cryogenic temperatures.
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Aloi E, Bartucci R. Influence of hydration on segmental chain librations and dynamical transition in lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183805. [PMID: 34662568 DOI: 10.1016/j.bbamem.2021.183805] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/29/2021] [Accepted: 10/10/2021] [Indexed: 12/23/2022]
Abstract
Continuous wave electron paramagnetic resonance spectroscopy of chain-labeled phospholipids is used to investigate the effects of hydration on the librational oscillations and the dynamical transition of phospholipid membranes in the low-temperature range 120-270 K. Bilayers of dipalmitoylphostatidiycholine (DPPC) spin-labeled at the first acyl chain segments and at the methyl ends and prepared at full, low, and very low hydration are considered. The segmental mean-square angular amplitudes of librations, 〈α2〉, are larger in the bilayer interior than at the polar/apolar interface and larger in the fully and low hydrated than in the very low hydrated membranes. For chain segments at the beginning of the hydrocarbon region, 〈α2〉-values are markedly restricted and temperature independent in DPPC with the lowest water content, whereas they increase with temperature in the low and fully hydrated bilayers, particularly at the highest temperatures. For chain segments at the chain termini, the librational amplitudes increase progressively, first slowly and then more rapidly with temperature in bilayers at any level of hydration. From the temperature dependence of the mean-square librational amplitude, the dynamical transition is detected around 240 K at the polar/apolar interface in fully and low hydrated DPPC and at around 225 K at the inner hydrocarbon region for bilayers at any hydration condition. At the dynamical transition the bilayers cross low energy barriers of activation energy in the range 10-20 kJ/mol. The results highlight biophysical properties of DPPC bilayers at low-temperature and provide evidence of the effects of the hydration on the dynamical transition in bilayers.
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Affiliation(s)
- Erika Aloi
- Department of Physics, Molecular Biophysics Laboratory, University of Calabria, 87036 Rende, (CS), Italy
| | - Rosa Bartucci
- Department of Chemistry and Chemical Technologies, Molecular Biophysics Laboratory, University of Calabria, 87036 Rende, (CS), Italy.
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Probing Small-Angle Molecular Motions with EPR Spectroscopy: Dynamical Transition and Molecular Packing in Disordered Solids. MAGNETOCHEMISTRY 2022. [DOI: 10.3390/magnetochemistry8020019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Disordered molecular solids present a rather broad class of substances of different origin—amorphous polymers, materials for photonics and optoelectronics, amorphous pharmaceutics, simple molecular glass formers, and others. Frozen biological media in many respects also may be referred to this class. Theoretical description of dynamics and structure of disordered solids still does not exist, and only some phenomenological models can be developed to explain results of particular experiments. Among different experimental approaches, electron paramagnetic resonance (EPR) applied to spin probes and labels also can deliver useful information. EPR allows probing small-angle orientational molecular motions (molecular librations), which intrinsically are inherent to all molecular solids. EPR is employed in its conventional continuous wave (CW) and pulsed—electron spin echo (ESE)—versions. CW EPR spectra are sensitive to dynamical librations of molecules while ESE probes stochastic molecular librations. In this review, different manifestations of small-angle motions in EPR of spin probes and labels are discussed. It is shown that CW-EPR-detected dynamical librations provide information on dynamical transition in these media, similar to that explored with neutron scattering, and ESE-detected stochastic librations allow elucidating some features of nanoscale molecular packing. The possible EPR applications are analyzed for gel-phase lipid bilayers, for biological membranes interacting with proteins, peptides and cryoprotectants, for supercooled ionic liquids (ILs) and supercooled deep eutectic solvents (DESs), for globular proteins and intrinsically disordered proteins (IDPs), and for some other molecular solids.
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Golysheva E, Maslennikova N, Baranov DS, Dzuba S. Structural properties of supercooled deep eutectic solvents: choline chloride–thiourea compared to reline. Phys Chem Chem Phys 2022; 24:5974-5981. [DOI: 10.1039/d1cp05162h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Deep eutectic solvents (DESs) are eutectic mixtures of hydrogen bond acceptors and hydrogen bond donors which melt at much lower temperatures than the individual components. DESs attract growing interest because...
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Ivanov MY, Surovtsev NV, Fedin MV. Ionic liquid glasses: properties and applications. RUSSIAN CHEMICAL REVIEWS 2022. [DOI: 10.1070/rcr5031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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de Wolf JR, Lenferink A, Lenferink A, Otto C, Bosschaart N. Evaluation of the changes in human milk lipid composition and conformational state with Raman spectroscopy during a breastfeed. BIOMEDICAL OPTICS EXPRESS 2021; 12:3934-3947. [PMID: 34457390 PMCID: PMC8367237 DOI: 10.1364/boe.427646] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/17/2021] [Accepted: 05/17/2021] [Indexed: 06/13/2023]
Abstract
Human milk fat forms the main energy source for breastfed infants, and is highly variable in terms of concentration and composition. Understanding the changes in human milk lipid composition and conformational state during a breastfeed can provide insight into lipid synthesis and secretion in the mammary gland. Therefore, the aim of this study was to evaluate human milk fatty acid length, degree of unsaturation (lipid composition) and lipid phase (lipid conformational state) at different stages during a single breastfeed (fore-, bulk- and hindmilk). A total of 48 samples from 16 lactating subjects were investigated with confocal Raman spectroscopy. We did not observe any significant changes in lipid composition between fore-, bulk and hindmilk. A new finding from this study is that lipid conformational state at room temperature changed significantly during a breastfeed, from almost crystalline to almost liquid. This observation suggests that lipid synthesis in the mammary gland changes during a single breastfeed.
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Affiliation(s)
- Johanna R. de Wolf
- Biomedical Photonic Imaging Group, Faculty of Science and Technology, Technical Medical Centre, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Anki Lenferink
- Biomedical Photonic Imaging Group, Faculty of Science and Technology, Technical Medical Centre, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Aufried Lenferink
- Medical Cell BioPhysics Group, Faculty of Science and Technology, Technical Medical Centre, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Cees Otto
- Medical Cell BioPhysics Group, Faculty of Science and Technology, Technical Medical Centre, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Nienke Bosschaart
- Biomedical Photonic Imaging Group, Faculty of Science and Technology, Technical Medical Centre, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
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9
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Aloi E, Bartucci R. Interdigitated lamellar phases in the frozen state: Spin-label CW- and FT-EPR. Biophys Chem 2019; 253:106229. [DOI: 10.1016/j.bpc.2019.106229] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/18/2019] [Accepted: 07/18/2019] [Indexed: 11/24/2022]
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Golysheva EA, Dzuba SA. Lipid chain mobility and packing in DOPC bilayers at cryogenic temperatures. Chem Phys Lipids 2019; 226:104817. [PMID: 31525380 DOI: 10.1016/j.chemphyslip.2019.104817] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/07/2019] [Accepted: 09/03/2019] [Indexed: 11/30/2022]
Abstract
Low-temperature molecular mobility and packing in biological tissues are important for their survival upon cryopreservation. Electron paramagnetic resonance (EPR) in its pulsed version of electron spin echo (ESE) allows studying stochastic librations of spin-labeled molecules, the type of motion which dominates at low temperatures. These librations are characterized by the parameter <α2>τc where <α2> is the mean squared angular amplitude and τc is the correlation time for the motion. This parameter is known to be larger for higher temperature and for looser intermolecular structure. In this work, ESE data for the bilayers comprised of doubly-unsaturated DOPC (dioleoyl-glycero-phosphocholine) lipids and mono-unsaturated POPC (palmitoyl-oleoyl-glycero-phosphocholine) lipids with spin-labeled stearic acids added were obtained in the temperature range between 80 and 210 K; the results were compared also with the previously obtained data for fully-saturated DPPC (dipalmitoyl-glycero-phosphocholine) lipid bilayers [J. Phys. Chem. B2014, 118, 12,478-12,485; Appl. Magn. Reson. 2018, 49, 1369-1383]. It turned out that for DOPC bilayers the <α2>τc values are of intermediate magnitude between those for POPC and DPPC bilayers, which implies an intermediate density of lipid packing. A possible explanation of this result could be rearrangement at cryogenic temperatures of the DOPC lipid tails, with their terminal segments folding cooperatively. This interpretation is also in agreement with the known thermodynamic properties of gel-fluid transition for DOPC bilayer.
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Affiliation(s)
- Elena A Golysheva
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk, 630090, Russian Federation; Department of Physics, Novosibirsk State University, Novosibirsk, 630090, Russian Federation
| | - Sergei A Dzuba
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk, 630090, Russian Federation; Department of Physics, Novosibirsk State University, Novosibirsk, 630090, Russian Federation.
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Aloi E, Guzzi R, Bartucci R. Unsaturated lipid bilayers at cryogenic temperature: librational dynamics of chain-labeled lipids from pulsed and CW-EPR. Phys Chem Chem Phys 2019; 21:18699-18705. [PMID: 31423504 DOI: 10.1039/c9cp03318a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fully hydrated bilayers of monounsaturated palmitoyloleoylphosphatidylcholine (POPC) and diunsaturated dioleoylphosphatidylcholine (DOPC) lipids have low main phase transition temperatures (271 K for POPC and 253 K for DOPC). Two-pulse echo detected spectra, combined with continuous wave electron paramagnetic resonance spectroscopy, are employed to study the low-temperature lamellar phases of the POPC and DOPC unsaturated bilayers that are usually studied in the fluid state. Phosphatidylcholine spin-labeled at C-5 and C-16 carbon atom positions along the acyl chain were used and the temperature varied over the range 77-270 K. Segmental chain librational oscillations of small amplitude and with correlation time in the subnanosecond to nanosecond range are found in both membranes. The mean-square angular amplitude, α2, of librations increases with temperature, is larger close to the bilayer midplane than close to the first acyl chain segments, and is larger in diunsaturated than in monounsaturated bilayers. In the inner hydrocarbon region of both lipid matrices, α2 increases first slowly and linearly with temperature and then more rapidly, and a dynamical transition is detected in the range 190-210 K. Compared to dipalmitoylphosphatidylcholine bilayers of fully saturated symmetric chain lipids, the presence of double bonds in the acyl chain enhances the intensity of librational motion which is characterized by larger angular variations at the terminal methyl ends. These findings highlight biophysical properties of unsaturated bilayers in the frozen state, including a detailed characterization of segmental chain dynamics and the evidence of a dynamical transition that appears to be a generic feature in hydrated macromolecular systems. These results can also be relevant in regulating membrane physical properties and function at higher physiological temperatures.
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Affiliation(s)
- Erika Aloi
- Department of Physics, Molecular Biophysics Laboratory, University of Calabria, 87036 Rende, Italy
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12
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Adishchev SV, Duda TA, Zaitseva YV, Zykova VA, Milekhin AG, Okotrub KA, Surovtsev NV. Stretch Vibrations of CH2 as a Measure of Conformational and Lateral Orders in Fatty Acid and Phospholipid Layers. ACTA ACUST UNITED AC 2019. [DOI: 10.3103/s875669901806002x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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Kuzhelev AA, Krumkacheva OA, Ivanov MY, Prikhod'ko SA, Adonin NY, Tormyshev VM, Bowman MK, Fedin MV, Bagryanskaya EG. Pulse EPR of Triarylmethyl Probes: A New Approach for the Investigation of Molecular Motions in Soft Matter. J Phys Chem B 2018; 122:8624-8630. [PMID: 30137993 DOI: 10.1021/acs.jpcb.8b07714] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Triarylmethyl (TAM) radicals have become widely used free radicals in the past few years. Their electron spins have long relaxation times and narrow electron paramagnetic resonance (EPR) lines, which make them an important class of probes and tags in biological applications and materials science. In this work, we propose a new approach to characterize librations by means of TAM radicals. The temperature dependence of motional parameter ⟨α2⟩τc, where ⟨α2⟩ is the mean-squared amplitude of librations and τc is their characteristic time, is obtained by comparison of the 1/ Tm phase-relaxation rates at X- and Q-band EPR frequencies. We study three soft matrixes, viz., glassy trehalose and two ionic liquids, using TAMs with optimized relaxation properties OX063D and a dodeca- n-butyl homologue of Finland trityl (DBT). The motional parameters ⟨α2⟩τc obtained using TAMs are in excellent agreement with those obtained by means of nitroxide radicals. At the same time, the new TAM-based approach has (1) greater sensitivity due to the narrower EPR spectrum and (2) greater measuring accuracy and broader temperature range due to longer relaxation times. The developed approach may be fruitfully implemented to probe low-temperature molecular motions of TAM-labeled biopolymers, membrane systems, polymers, molecules in glassy media, and ionic liquids.
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Affiliation(s)
- Andrey A Kuzhelev
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS , Novosibirsk 630090 , Russia.,International Tomography Center SB RAS , Novosibirsk 630090 , Russia.,Novosibirsk State University , Novosibirsk 630090 , Russia
| | - Olesya A Krumkacheva
- International Tomography Center SB RAS , Novosibirsk 630090 , Russia.,Novosibirsk State University , Novosibirsk 630090 , Russia
| | - Mikhail Yu Ivanov
- International Tomography Center SB RAS , Novosibirsk 630090 , Russia.,Novosibirsk State University , Novosibirsk 630090 , Russia
| | | | - Nicolay Yu Adonin
- Boreskov Institute of Catalysis SB RAS , Novosibirsk 630090 , Russia
| | - Victor M Tormyshev
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS , Novosibirsk 630090 , Russia.,Novosibirsk State University , Novosibirsk 630090 , Russia
| | - Michael K Bowman
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS , Novosibirsk 630090 , Russia.,University of Alabama , Tuscaloosa , Alabama 35487-0336 , United States
| | - Matvey V Fedin
- International Tomography Center SB RAS , Novosibirsk 630090 , Russia.,Novosibirsk State University , Novosibirsk 630090 , Russia
| | - Elena G Bagryanskaya
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS , Novosibirsk 630090 , Russia.,Novosibirsk State University , Novosibirsk 630090 , Russia
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Golysheva EA, Shevelev GY, Dzuba SA. Dynamical transition in molecular glasses and proteins observed by spin relaxation of nitroxide spin probes and labels. J Chem Phys 2018; 147:064501. [PMID: 28810753 DOI: 10.1063/1.4997035] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In glassy substances and biological media, dynamical transitions are observed in neutron scattering that manifests itself as deviations of the translational mean-squared displacement, 〈x2〉, of hydrogen atoms from harmonic dynamics. In biological media, the deviation occurs at two temperature intervals, at ∼100-150 K and at ∼170-230 K, and it is attributed to the motion of methyl groups in the former case and to the transition from harmonic to anharmonic or diffusive motions in the latter case. In this work, electron spin echo (ESE) spectroscopy-a pulsed version of electron paramagnetic resonance-is applied to study the spin relaxation of nitroxide spin probes and labels introduced in molecular glass former o-terphenyl and in protein lysozyme. The anisotropic contribution to the rate of the two-pulse ESE decay, ΔW, is induced by spin relaxation appearing because of restricted orientational stochastic molecular motion; it is proportional to 〈α2〉τc, where 〈α2〉 is the mean-squared angle of reorientation of the nitroxide molecule around the equilibrium position and τc is the correlation time of reorientation. The ESE time window allows us to study motions with τc < 10-7 s. For glassy o-terphenyl, the 〈α2〉τc temperature dependence shows a transition near 240 K, which is in agreement with the literature data on 〈x2〉. For spin probes of essentially different size, the obtained data were found to be close, which evidences that motion is cooperative, involving a nanocluster of several neighboring molecules. For the dry lysozyme, the 〈α2〉τc values below 260 K were found to linearly depend on the temperature in the same way as it was observed in neutron scattering for 〈x2〉. As spin relaxation is influenced only by stochastic motion, the harmonic motions seen in ESE must be overdamped. In the hydrated lysozyme, ESE data show transitions near 130 K for all nitroxides, near 160 K for the probe located in the hydration layer, and near 180 K for the label in the protein interior. For this system, the two latter transitions are not observed in neutron scattering. The ESE-detected transitions are suggested to be related with water dynamics in the nearest hydration shell: with water glass transition near 130 K and with the onset of overall water molecular reorientations near 180 K; the disagreement with neutron scattering is ascribed to the larger time window for ESE-detected motions.
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Affiliation(s)
- Elena A Golysheva
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russian Federation
| | - Georgiy Yu Shevelev
- Department of Physics, Novosibirsk State University, Novosibirsk 630090, Russian Federation
| | - Sergei A Dzuba
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russian Federation
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15
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Okotrub K, Amstislavsky S, Surovtsev N. Raman spectroscopy reveals the lipid phase transition in preimplantation mouse embryos during freezing. Arch Biochem Biophys 2017; 635:37-43. [DOI: 10.1016/j.abb.2017.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/02/2017] [Accepted: 10/04/2017] [Indexed: 11/27/2022]
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16
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Aloi E, Oranges M, Guzzi R, Bartucci R. Low-Temperature Dynamics of Chain-Labeled Lipids in Ester- and Ether-Linked Phosphatidylcholine Membranes. J Phys Chem B 2017; 121:9239-9246. [PMID: 28892381 DOI: 10.1021/acs.jpcb.7b07386] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Continuous wave electron paramagnetic resonance spectroscopy and two-pulse echo detected spectra of chain-labeled lipids are used to study the dynamics of frozen lipid membranes over the temperature range 77-260 K. Bilayers of ester-linked dihexadecanoylphosphatidylcholine (DPPC) with noninterdigitated chains and ether-linked dihexadecyl phosphatidylcholine (DHPC) with interdigitated chains are considered. Rapid stochastic librations of small angular amplitude are found in both lipid matrices. In noninterdigitated DPPC bilayers, the mean-square angular amplitude, [Formula: see text], of the motion increases with temperature and it is larger close to the chain termini than close to the polar/apolar interface. In contrast, in interdigitated DHPC lamellae, [Formula: see text] is small and temperature and label-position independent at low temperature and increases steeply at high temperature. The rotational correlation time, τc, of librations lies in the subnanosecond range for DPPC and in the nanosecond range for DHPC. In all membrane samples, the temperature dependence of [Formula: see text] resembles that of the mean-square atomic displacement revealed by neutron scattering and a dynamical transition is detected in the range 210-240 K. The results highlight the librational oscillations and the glass-like behavior in bilayer and interdigitated lipid membranes.
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Affiliation(s)
- Erika Aloi
- Department of Physics, Molecular Biophysics Laboratory, University of Calabria , 87036 Rende (CS), Italy
| | - Maria Oranges
- Department of Physics, Molecular Biophysics Laboratory, University of Calabria , 87036 Rende (CS), Italy
| | - Rita Guzzi
- Department of Physics, Molecular Biophysics Laboratory, University of Calabria , 87036 Rende (CS), Italy
| | - Rosa Bartucci
- Department of Physics, Molecular Biophysics Laboratory, University of Calabria , 87036 Rende (CS), Italy
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Surovtsev NV, Dmitriev AA, Dzuba SA. Normal vibrational modes of phospholipid bilayers observed by low-frequency Raman scattering. Phys Rev E 2017; 95:032412. [PMID: 28415343 DOI: 10.1103/physreve.95.032412] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Indexed: 06/07/2023]
Abstract
Low-frequency Raman spectra of multilamellar vesicles made either of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) have been studied in a wide temperature range. Below 0^{∘}C two peaks are found at frequencies around 8-9 and 14-17cm^{-1} and attributed to the normal vibrational modes of the phospholipid bilayer, which are determined by the bilayer thickness and stiffness (elastic modulus). The spectral positions of the peaks depend on the temperature and the bilayer composition. It is suggested that the ratio of the intensities of the first and second peaks can serve as a measure of the interleaflet elastic coupling. The addition of cholesterol to the phospholipid bilayer leads to peak shift and broadening, which may be assigned to the composition heterogeneities commonly attributed to the lipid raft formation.
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Affiliation(s)
- N V Surovtsev
- Institute of Automation and Electrometry, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - A A Dmitriev
- Institute of Automation and Electrometry, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - S A Dzuba
- Novosibirsk State University, Novosibirsk 630090, Russia
- Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russia
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18
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Syryamina VN, Dzuba SA. Dynamical Transitions at Low Temperatures in the Nearest Hydration Shell of Phospholipid Bilayers. J Phys Chem B 2017; 121:1026-1032. [DOI: 10.1021/acs.jpcb.6b10133] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- V. N. Syryamina
- Institute
of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russian Federation
- Physics
Department, Novosibirsk State University, Novosibirsk 630090, Russian Federation
| | - S. A. Dzuba
- Institute
of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russian Federation
- Physics
Department, Novosibirsk State University, Novosibirsk 630090, Russian Federation
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19
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Ivanov MY, Krumkacheva OA, Dzuba SA, Fedin MV. Microscopic rigidity and heterogeneity of ionic liquids probed by stochastic molecular librations of the dissolved nitroxides. Phys Chem Chem Phys 2017; 19:26158-26163. [DOI: 10.1039/c7cp04890d] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We propose a new potent approach for studying nano/microscopic heterogeneities in ionic liquids exploiting stochastic librations of nitroxides and pulse EPR.
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Affiliation(s)
- Mikhail Yu. Ivanov
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Olesya A. Krumkacheva
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Sergei A. Dzuba
- Novosibirsk State University
- Novosibirsk
- Russia
- Voevodsky Institute of Chemical Kinetics and Combustion SB RAS
- Novosibirsk
| | - Matvey V. Fedin
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
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20
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Dmitriev AA, Surovtsev NV. Temperature-Dependent Hydrocarbon Chain Disorder in Phosphatidylcholine Bilayers Studied by Raman Spectroscopy. J Phys Chem B 2015; 119:15613-22. [DOI: 10.1021/acs.jpcb.5b07502] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. A. Dmitriev
- Novosibirsk State University, Novosibirsk, 630090, Russia
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21
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Disalvo E, Pinto O, Martini M, Bouchet A, Hollmann A, Frías M. Functional role of water in membranes updated: A tribute to Träuble. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1552-62. [DOI: 10.1016/j.bbamem.2015.03.031] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 03/20/2015] [Accepted: 03/26/2015] [Indexed: 11/30/2022]
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22
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Guzzi R, Bartucci R, Esmann M, Marsh D. Lipid Librations at the Interface with the Na,K-ATPase. Biophys J 2015; 108:2825-32. [PMID: 26083922 DOI: 10.1016/j.bpj.2015.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/22/2015] [Accepted: 05/06/2015] [Indexed: 10/23/2022] Open
Abstract
Transitions between conformational substates of membrane proteins can be driven by torsional librations in the protein that may be coupled to librational fluctuations of the lipid chains. Here, librational motion of spin-labeled lipid chains in membranous Na,K-ATPase is investigated by spin-echo electron paramagnetic resonance. Lipids at the protein interface are targeted by using negatively charged spin-labeled fatty acids that display selectivity of interaction with the Na,K-ATPase. Echo-detected electron paramagnetic resonance spectra from native membranes are corrected for the contribution from the bilayer regions of the membrane by using spectra from dispersions of the extracted membrane lipids. Lipid librations at the protein interface have a flat profile with chain position, whereas librational fluctuations of the bilayer lipids increase pronouncedly from C-9 onward, then flatten off toward the terminal methyl end of the chains. This difference is accounted for by increased torsional amplitude at the chain ends in bilayers, while the amplitude remains restricted throughout the chain at the protein interface with a limited lengthening in correlation time. The temperature dependence of chain librations at the protein interface strongly resembles that of the spin-labeled protein side chains, suggesting solvent-mediated transitions in the protein are driven by fluctuations in the lipid environment.
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Affiliation(s)
- Rita Guzzi
- Department of Physics, Molecular Biophysics Laboratory and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Material Unit, University of Calabria, Ponte P. Bucci, Rende, Italy
| | - Rosa Bartucci
- Department of Physics, Molecular Biophysics Laboratory and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Material Unit, University of Calabria, Ponte P. Bucci, Rende, Italy
| | - Mikael Esmann
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Derek Marsh
- Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany.
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23
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Konov KB, Isaev NP, Dzuba SA. Low-Temperature Molecular Motions in Lipid Bilayers in the Presence of Sugars: Insights into Cryoprotective Mechanisms. J Phys Chem B 2014; 118:12478-85. [DOI: 10.1021/jp508312n] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Konstantin B. Konov
- Zavoisky
Physical-Technical Institute, Russian Academy of Sciences, Kazan 420029, Russia
| | - Nikolay P. Isaev
- Voevodsky
Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Sergei A. Dzuba
- Voevodsky
Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk, 630090, Russia
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24
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Pinto OA, Bouchet AM, Frías MA, Disalvo EA. Microthermodynamic Interpretation of Fluid States from FTIR Measurements in Lipid Membranes: A Monte Carlo Study. J Phys Chem B 2014; 118:10436-43. [DOI: 10.1021/jp5044078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- O. A. Pinto
- Centro de Investigaciones y Transferencia
de Santiago del Estero
(CITSE) and ‡Laboratorio de Biointerfases y Sistemas Biomiméticos, Centro
de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago de Estero, CONICET RN 9 Km 1125 Villa el Zanjón, Santiago del Estero, CP 4206 Argentina
| | - A. M. Bouchet
- Centro de Investigaciones y Transferencia
de Santiago del Estero
(CITSE) and ‡Laboratorio de Biointerfases y Sistemas Biomiméticos, Centro
de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago de Estero, CONICET RN 9 Km 1125 Villa el Zanjón, Santiago del Estero, CP 4206 Argentina
| | - M. A. Frías
- Centro de Investigaciones y Transferencia
de Santiago del Estero
(CITSE) and ‡Laboratorio de Biointerfases y Sistemas Biomiméticos, Centro
de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago de Estero, CONICET RN 9 Km 1125 Villa el Zanjón, Santiago del Estero, CP 4206 Argentina
| | - E. A. Disalvo
- Centro de Investigaciones y Transferencia
de Santiago del Estero
(CITSE) and ‡Laboratorio de Biointerfases y Sistemas Biomiméticos, Centro
de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago de Estero, CONICET RN 9 Km 1125 Villa el Zanjón, Santiago del Estero, CP 4206 Argentina
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25
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Surovtsev NV, Dzuba SA. Flexibility of phospholipids with saturated and unsaturated chains studied by Raman scattering: The effect of cholesterol on dynamical and phase transitions. J Chem Phys 2014; 140:235103. [DOI: 10.1063/1.4883237] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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26
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Disalvo EA, Bouchet AM, Frias MA. Connected and isolated CH2 populations in acyl chains and its relation to pockets of confined water in lipid membranes as observed by FTIR spectrometry. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1683-9. [PMID: 23500348 DOI: 10.1016/j.bbamem.2013.02.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 01/15/2013] [Accepted: 02/13/2013] [Indexed: 11/18/2022]
Abstract
Analysis of the band corresponding to the frequency of vibrational symmetric stretching mode of methylene groups in the lipid acyl chains and the bands of water below and above the phase transition of different lipids by Fourier transform infrared spectroscopy gives strong support to the formation of confined water pockets in between the lipid acyl chains. Our measures and analysis consolidate the mechanism early proposed by Traüble, in the sense that water is present in kinks formed by trans-gauche isomers along the hydrocarbon tails. The formation of these regions depends on the acyl lipid composition, which determines the presence of different populations of water species, characterized by its degree of H bond coordination in fluid saturated or unsaturated lipids. The free energy excess due to the reinforcement of the water structure along few water molecules in the adjacencies of exposed membrane residues near the phase transition is a reasonable base to explain the insertion and translocation of polar peptides and amino acid residues through the biomembrane on thermodynamic and structural grounds.
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Affiliation(s)
- E A Disalvo
- Universidad Nacional de Santiago del Estero, Santiago del Estero, Argentina.
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