1
|
Roversi D, Troiano C, Salnikov E, Giordano L, Riccitelli F, De Zotti M, Casciaro B, Loffredo MR, Park Y, Formaggio F, Mangoni ML, Bechinger B, Stella L. Effects of antimicrobial peptides on membrane dynamics: A comparison of fluorescence and NMR experiments. Biophys Chem 2023; 300:107060. [PMID: 37336097 DOI: 10.1016/j.bpc.2023.107060] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/25/2023] [Accepted: 06/02/2023] [Indexed: 06/21/2023]
Abstract
Antimicrobial peptides (AMPs) represent a promising class of compounds to fight resistant infections. They are commonly thought to kill bacteria by perturbing the permeability of their cell membranes. However, bacterial killing requires a high coverage of the cell surface by bound peptides, at least in the case of cationic and amphipathic AMPs. Therefore, it is conceivable that peptide accumulation on the bacterial membranes might interfere with vital cellular functions also by perturbing bilayer dynamics, a hypothesis that has been termed "sand in the gearbox". Here we performed a systematic study of such possible effects, for two representative peptides (the cationic cathelicidin PMAP-23 and the peptaibol alamethicin), employing fluorescence and NMR spectroscopies. These approaches are commonly applied to characterize lipid order and dynamics, but sample different time-scales and could thus report on different membrane properties. In our case, fluorescence anisotropy measurements on liposomes labelled with probes localized at different depths in the bilayer showed that both peptides perturb membrane fluidity and order. Pyrene excimer-formation experiments showed a peptide-induced reduction in lipid lateral mobility. Finally, laurdan fluorescence indicated that peptide binding reduces water penetration below the headgroups region. Comparable effects were observed also in fluorescence experiments performed directly on live bacterial cells. By contrast, the fatty acyl chain order parameters detected by deuterium NMR spectroscopy remained virtually unaffected by addition of the peptides. The apparent discrepancy between the two techniques confirms previous sporadic observations and is discussed in terms of the different characteristic times of the two approaches. The perturbation of membrane dynamics in the ns timescale, indicated by the multiple fluorescence approaches reported here, could contribute to the antimicrobial activity of AMPs, by affecting the function of membrane proteins, which is strongly dependent on the physicochemical properties of the bilayer.
Collapse
Affiliation(s)
- Daniela Roversi
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Cassandra Troiano
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Evgeniy Salnikov
- RMN et Biophysique des membranes, Institut de Chimie de Strasbourg, CNRS/UMR 7177, Université de Strasbourg, 4, rue Blaise Pascal, Strasbourg 67000, France
| | - Lorenzo Giordano
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Francesco Riccitelli
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy
| | - Marta De Zotti
- Department of Chemical Sciences, University of Padova, Padova 35131, Italy
| | - Bruno Casciaro
- Department of Biochemical Sciences, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome 00185, Italy
| | - Maria Rosa Loffredo
- Department of Biochemical Sciences, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome 00185, Italy
| | - Yoonkyung Park
- Department of Biomedical Science and Research Center for Proteinaceous Materials (RCPM), Chosun University, Gwangju, Republic of Korea
| | - Fernando Formaggio
- Department of Chemical Sciences, University of Padova, Padova 35131, Italy
| | - Maria Luisa Mangoni
- Department of Biochemical Sciences, Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome 00185, Italy
| | - Burkhard Bechinger
- RMN et Biophysique des membranes, Institut de Chimie de Strasbourg, CNRS/UMR 7177, Université de Strasbourg, 4, rue Blaise Pascal, Strasbourg 67000, France; Institut Universitaire de France, Paris 75005, France
| | - Lorenzo Stella
- Department of Chemical Science and Technology, University of Rome Tor Vergata, Rome 00133, Italy.
| |
Collapse
|
2
|
Santhosh PB, Tenev T, Šturm L, Ulrih NP, Genova J. Effects of Hydrophobic Gold Nanoparticles on Structure and Fluidity of SOPC Lipid Membranes. Int J Mol Sci 2023; 24:10226. [PMID: 37373371 DOI: 10.3390/ijms241210226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 05/31/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Gold nanoparticles (AuNPs) are promising candidates in various biomedical applications such as sensors, imaging, and cancer therapy. Understanding the influence of AuNPs on lipid membranes is important to assure their safety in the biological environment and to improve their scope in nanomedicine. In this regard, the present study aimed to analyze the effects of different concentrations (0.5, 1, and 2 wt.%) of dodecanethiol functionalized hydrophobic AuNPs on the structure and fluidity of zwitterionic 1-stearoyl-2-oleoyl-sn-glycerol-3-phosphocholine (SOPC) lipid bilayer membranes using Fourier-transform infrared (FTIR) spectroscopy and fluorescent spectroscopy. The size of AuNPs was found to be 2.2 ± 1.1 nm using transmission electron microscopy. FTIR results have shown that the AuNPs induced a slight shift in methylene stretching bands, while the band positions of carbonyl and phosphate group stretching were unaffected. Temperature-dependent fluorescent anisotropy measurements showed that the incorporation of AuNPs up to 2 wt.% did not affect the lipid order in membranes. Overall, these results indicate that the hydrophobic AuNPs in the studied concentration did not cause any significant alterations in the structure and membrane fluidity, which suggests the suitability of these particles to form liposome-AuNP hybrids for diverse biomedical applications including drug delivery and therapy.
Collapse
Affiliation(s)
- Poornima Budime Santhosh
- Institute of Solid State Physics, Bulgarian Academy of Sciences, Tzarigradsko Chaussee 72, 1784 Sofia, Bulgaria
| | - Tihomir Tenev
- Institute of Solid State Physics, Bulgarian Academy of Sciences, Tzarigradsko Chaussee 72, 1784 Sofia, Bulgaria
| | - Luka Šturm
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Nataša Poklar Ulrih
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Julia Genova
- Institute of Solid State Physics, Bulgarian Academy of Sciences, Tzarigradsko Chaussee 72, 1784 Sofia, Bulgaria
| |
Collapse
|
3
|
Liposomes for encapsulation of liposoluble vitamins (A, D, E and K): Comparation of loading ability, storage stability and bilayer dynamics. Food Res Int 2023; 163:112264. [PMID: 36596175 DOI: 10.1016/j.foodres.2022.112264] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/22/2022] [Accepted: 11/27/2022] [Indexed: 12/04/2022]
Abstract
To understand the encapsulation difference and stability mechanism of nanoliposomes (NLPs) loaded with different kinds and loads of liposoluble vitamins (LSV, including VA, VD, VE, and VK), the physicochemical stability during three-months storage and bilayer membrane properties of LSV-NLPs were evaluated. The results suggested that VD and VE were not suitable for high-load (≥30 wt%) encapsulation, but the stability of other LSV-NLPs was excellent during storage. Their particle size was less than 100 nm, the polydispersity index was less than 0.3, and the retention rate of VE and VK remained above 85 %. LSV encapsulation inhibited malondialdehyde production, decreased liposome surface roughness, and improved nanoliposome rigidity. The order of occupying capacity of LSV to the hydrophobic zone of the bilayer was VK>VD>VE>VA, and the stability of LSV located in the hydrophobic region was better. Except for high-load VD and VE, the other LSV encapsulation increased the microviscosity of the lipid-water interface and hydrophobic zone by 0.5 ∼ 7.1 times and 0.5 ∼ 20 times, respectively. The accumulation of acyl chain was enhanced by 0.2 ∼ 4 times, and the interchain longitudinal and intra-chain transverse order degree was increased by 10.89 %∼144.35 % and 3.26 %∼115.52 %, respectively. High microviscosity and tight chain stacking limited bilayer fluidity and thus improve LSV-NLPs stability. This work will contribute to the application of nanoliposomes as liposoluble vitamin carriers in the food industry.
Collapse
|
4
|
Ning H, Cong Y, Lin H, Wang J. Development of cationic peptide chimeric lysins based on phage lysin Lysqdvp001 and their antibacterial effects against Vibrio parahaemolyticus: A preliminary study. Int J Food Microbiol 2021; 358:109396. [PMID: 34560361 DOI: 10.1016/j.ijfoodmicro.2021.109396] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/26/2021] [Accepted: 09/03/2021] [Indexed: 01/22/2023]
Abstract
Cationic peptide chimeric lysins, Lysqdvp001-5aa, Lysqdvp001-10aa and Lysqdvp001-15aa, were designed based on lysin Lysqdvp001 from Vibrio parahaemolyticus (V. parahaemolyticus) phage qdvp001. These chimeric lysins showed equivalent peptidoglycan hydrolysis activities with Lysqdvp001 and could lyse the bacteria from the outside. The antibacterial activity as well as outer and inner membrane permeabilization of Lysqdvp001 and chimeric lysins against V. parahaemolyticus were Lysqdvp001-15aa>Lysqdvp001-10aa>Lysqdvp001-5aa>Lysqdvp001. Lysqdvp001-15aa exhibited an excellent antibacterial activity with minimum inhibition and bactericidal concentrations (MIC and MBC) of 0.2 and 0.4 mg/mL, respectively, and its antibacterial spectrum was much broader than phage qdvp001. Membrane hyperpolarization and membrane phospholipid exposure of V. parahaemolyticus were observed after Lysqdvp001-15aa treatments. Transmission electron microscope (TEM) showed Lysqdvp001-15aa destroyed structure integrity of V. parahaemolyticus. Besides, MIC and MBC of Lysqdvp001-15aa decreased V. parahaemolyticus counts in oyster by 3.20 and 4.03 log10CFU/g. Lysqdvp001-15aa at MBC eradicated about 50% of V. parahaemolyticus biofilms and inhibited over 90% of the formation of the bacterial biofilms.
Collapse
Affiliation(s)
- Houqi Ning
- College of Food Science and Engineering, Ocean University of China, No. 5, Yushan Road, Qingdao, Shandong Province 266003, PR China
| | - Yu Cong
- College of Food Science and Engineering, Ocean University of China, No. 5, Yushan Road, Qingdao, Shandong Province 266003, PR China
| | - Hong Lin
- College of Food Science and Engineering, Ocean University of China, No. 5, Yushan Road, Qingdao, Shandong Province 266003, PR China
| | - Jingxue Wang
- College of Food Science and Engineering, Ocean University of China, No. 5, Yushan Road, Qingdao, Shandong Province 266003, PR China.
| |
Collapse
|
5
|
LI NS, CHEN L, XIAO ZX, YANG YQ, AI KL. Progress in Detection of Biomarker of Ovarian Cancer: Lysophosphatidic Acid. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1016/s1872-2040(20)60062-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
6
|
Filipe HAL, Moreno MJ, Loura LMS. The Secret Lives of Fluorescent Membrane Probes as Revealed by Molecular Dynamics Simulations. Molecules 2020; 25:E3424. [PMID: 32731549 PMCID: PMC7435664 DOI: 10.3390/molecules25153424] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/23/2020] [Accepted: 07/25/2020] [Indexed: 12/15/2022] Open
Abstract
Fluorescent probes have been employed for more than half a century to study the structure and dynamics of model and biological membranes, using spectroscopic and/or microscopic experimental approaches. While their utilization has led to tremendous progress in our knowledge of membrane biophysics and physiology, in some respects the behavior of bilayer-inserted membrane probes has long remained inscrutable. The location, orientation and interaction of fluorophores with lipid and/or water molecules are often not well known, and they are crucial for understanding what the probe is actually reporting. Moreover, because the probe is an extraneous inclusion, it may perturb the properties of the host membrane system, altering the very properties it is supposed to measure. For these reasons, the need for independent methodologies to assess the behavior of bilayer-inserted fluorescence probes has been recognized for a long time. Because of recent improvements in computational tools, molecular dynamics (MD) simulations have become a popular means of obtaining this important information. The present review addresses MD studies of all major classes of fluorescent membrane probes, focusing in the period between 2011 and 2020, during which such work has undergone a dramatic surge in both the number of studies and the variety of probes and properties accessed.
Collapse
Affiliation(s)
- Hugo A. L. Filipe
- Chemistry Department, Coimbra Chemistry Center, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal;
| | - Maria João Moreno
- Coimbra Chemistry Center and CNC—Center for Neuroscience and Cell Biology, Chemistry Department, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal;
| | - Luís M. S. Loura
- Coimbra Chemistry Center and CNC—Center for Neuroscience and Cell Biology, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| |
Collapse
|
7
|
Li M, Wang S, Xu J, Xu S, Liu H. pH/Redox-Controlled Interaction between Lipid Membranes and Peptide Derivatives with a "Helmet". J Phys Chem B 2019; 123:6784-6791. [PMID: 31306021 DOI: 10.1021/acs.jpcb.9b05367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
How to reduce the cytotoxicity of antitumor peptides to normal cells remains an ongoing challenge. Here, we designed a pH/redox-responsive supramolecular structure (Pep-V⊂P-PEG) composed of a peptide modified with viologen (Pep-V) and polyethylene glycol bearing pillar[5]arene (P-PEG) as a "helmet". By shielding the hydrophobic moiety of the peptide derivative with pillar[5]arene via host-guest interactions, its disruption on normal cells can be effectively reduced. At acidic pH, the supramolecular structure can selectively adsorb onto negatively charged lipid membranes because of electrostatic interactions. Owing to redox responsiveness of the viologen group, Pep-V could be separated from P-PEG after the addition of reductants and inserted into lipid bilayers, which leads to membrane disruption. Cargo leakage of liposome models was investigated to understand Pep-V⊂P-PEG-induced liposomal membrane disruption under different pH values and redox conditions. Results showed that Pep-V⊂P-PEG caused almost no cargo leakage from (1,2-dipalmitoyl-sn-glycerol-3-phosphocholine) liposomes at pH 7.4 but significant leakage from negatively charged (1,2-dipalmitoyl-sn-glycerol-3-phospho-(1-rac-glyerol)) liposomes at pH 5.0 under a reducing environment. Pep-V⊂P-PEG displayed low destructive effects on mimic normal cells and significant disruption to mimic tumor cells when exposed to a reducing environment that is expected to be a potential antitumor agent.
Collapse
Affiliation(s)
- Mengya Li
- Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering , East China University of Science and Technology , Shanghai 200237 , PR China
| | - Sijia Wang
- College of Pharmacy , Henan University of Chinese Medicine , Zhengzhou 450046 , PR China
| | - Jun Xu
- Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering , East China University of Science and Technology , Shanghai 200237 , PR China
| | - Shouhong Xu
- Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering , East China University of Science and Technology , Shanghai 200237 , PR China
| | - Honglai Liu
- Key Laboratory for Advanced Materials, School of Chemistry and Molecular Engineering , East China University of Science and Technology , Shanghai 200237 , PR China
| |
Collapse
|
8
|
Striking Features of DPH Electronic Spectra as a Function of Multicomponent Solvent Nature. J SOLUTION CHEM 2018. [DOI: 10.1007/s10953-018-0803-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Wang S, Han X, Liu D, Li M, Xu S, Liu H. Melting Behavior of Zipper-Structured Lipopeptides in Lipid Bilayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:1478-1485. [PMID: 28099806 DOI: 10.1021/acs.langmuir.6b04080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A zipper-structured lipopeptide is expected to play a role of "intelligent valve" in the lipid bilayer. In this paper, a series of zipper-structured lipopeptides have been designed for preparing thermocontrollable hybrid liposomes. Their conformational transition as a function of temperature in lipid bilayer has been investigated for understanding the influences of molecular structure and bilayer property on biofunction. The melting temperatures Tm of the lipopeptides have been found to depend on their molecular structures. When the lipopeptides have been doped in bilayer, an increase of size of alkyl chain increases the stability of the α-helix resulting in a decrease in fluidity of lipid bilayer. However, an increase of amino groups at N-terminal is found to decrease the stability of the spatial structure. The thermocontrollability of the "valve" in lipid bilayer is confirmed by drug release experiments under different temperatures. Meanwhile, effects of bilayer properties on the thermosensitivity of lipopeptides have also been investigated. Results show the Tm of lipopeptide doped in bilayer decreases with the increase of membrane fluidity. Furthermore, the reversibility of the thermocontrolled "valve" is also proven by release drug under intermittent temperatures. It could be concluded that the molecular structure of the lipopeptide, as well as the property of bilayer, give great influence on the biofunction of the hybrid liposomes.
Collapse
Affiliation(s)
- Sijia Wang
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology , Shanghai, 200237, China
| | - Xia Han
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology , Shanghai, 200237, China
| | - Danyang Liu
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology , Shanghai, 200237, China
| | - Mengya Li
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology , Shanghai, 200237, China
| | - Shouhong Xu
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology , Shanghai, 200237, China
| | - Honglai Liu
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology , Shanghai, 200237, China
| |
Collapse
|
10
|
do Canto AMTM, Robalo JR, Santos PD, Carvalho AJP, Ramalho JPP, Loura LMS. Diphenylhexatriene membrane probes DPH and TMA-DPH: A comparative molecular dynamics simulation study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2647-2661. [PMID: 27475296 DOI: 10.1016/j.bbamem.2016.07.013] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 07/05/2016] [Accepted: 07/25/2016] [Indexed: 10/21/2022]
Abstract
Fluorescence spectroscopy and microscopy have been utilized as tools in membrane biophysics for decades now. Because phospholipids are non-fluorescent, the use of extrinsic membrane probes in this context is commonplace. Among the latter, 1,6-diphenylhexatriene (DPH) and its trimethylammonium derivative (TMA-DPH) have been extensively used. It is widely believed that, owing to its additional charged group, TMA-DPH is anchored at the lipid/water interface and reports on a bilayer region that is distinct from that of the hydrophobic DPH. In this study, we employ atomistic MD simulations to characterize the behavior of DPH and TMA-DPH in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and POPC/cholesterol (4:1) bilayers. We show that although the dynamics of TMA-DPH in these membranes is noticeably more hindered than that of DPH, the location of the average fluorophore of TMA-DPH is only ~3-4Å more shallow than that of DPH. The hindrance observed in the translational and rotational motions of TMA-DPH compared to DPH is mainly not due to significant differences in depth, but to the favorable electrostatic interactions of the former with electronegative lipid atoms instead. By revealing detailed insights on the behavior of these two probes, our results are useful both in the interpretation of past work and in the planning of future experiments using them as membrane reporters.
Collapse
Affiliation(s)
- António M T M do Canto
- Centro de Química de Évora e Departamento de Química, Escola de Ciências e Tecnologia, Colégio Luís Verney, Rua Romão Ramalho 59, P-7002-554 Évora, Portugal
| | - João R Robalo
- Centro de Química de Évora e Departamento de Química, Escola de Ciências e Tecnologia, Colégio Luís Verney, Rua Romão Ramalho 59, P-7002-554 Évora, Portugal; Theory and Bio-Systems Department, Max Planck Institute of Colloids and Interfaces, Wissenschaftspark Golm, D-14424 Potsdam, Germany
| | - Patrícia D Santos
- Centro de Química de Évora e Departamento de Química, Escola de Ciências e Tecnologia, Colégio Luís Verney, Rua Romão Ramalho 59, P-7002-554 Évora, Portugal
| | - Alfredo J Palace Carvalho
- Centro de Química de Évora e Departamento de Química, Escola de Ciências e Tecnologia, Colégio Luís Verney, Rua Romão Ramalho 59, P-7002-554 Évora, Portugal
| | - J P Prates Ramalho
- Centro de Química de Évora e Departamento de Química, Escola de Ciências e Tecnologia, Colégio Luís Verney, Rua Romão Ramalho 59, P-7002-554 Évora, Portugal
| | - Luís M S Loura
- Faculdade de Farmácia, Universidade de Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, P-3000-548 Coimbra, Portugal; Centro de Química de Coimbra, Largo D. Dinis, Rua Larga, P-3004-535 Coimbra, Portugal.
| |
Collapse
|
11
|
Poger D, Mark AE. Effect of Ring Size in ω-Alicyclic Fatty Acids on the Structural and Dynamical Properties Associated with Fluidity in Lipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11574-11582. [PMID: 26444798 DOI: 10.1021/acs.langmuir.5b02635] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Fatty acids containing a terminal cyclic group such as cyclohexyl and cycloheptyl are commonly found in prokaryotic membranes, especially in those of thermo-acidophilic bacteria. These so-called ω-alicyclic fatty acids have been proposed to stabilize the membranes of bacteria by reducing the fluidity in membranes and increasing lipid packing and lipid chain order. In this article, molecular dynamics simulations are used to examine the effect of 3- to 7-membered cycloalkyl saturated and unsaturated (cyclopent-2-enyl and phenyl) rings in ω-alicyclic fatty acyl chains on the structure (lipid packing, lipid chain order, and fraction of gauche defects in the chains) and dynamics (lateral lipid diffusion) of a model lipid bilayer. It was found that ω-alicyclic chains in which the ring was saturated reduced lipid condensation and lowered chain order which would be associated with enhanced fluidity. However, this effect was limited. The lateral diffusion of the lipids diminished as the ring size increased. In particular, ω-cyclohexyl and ω-cycloheptyl acyl tails led to a decrease in lipid diffusion. In contrast, ω-alicyclic acyl chains that contain an unsaturated ring promoted membrane fluidity both in terms of changes in membrane structure and lipid diffusion. This may indicate that saturated and unsaturated terminal rings in ω-alicyclic fatty acids fulfill alternative functions within membranes. Overall, the simulations suggest that ω-alicyclic fatty acids in which the terminal ring is saturated might protect the membrane of thermo-acidophilic bacteria from high-temperature and low-pH conditions through a "dynamical barrier" that would limit lipid diffusion and transmembrane diffusion of undesired ions and molecules.
Collapse
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
| |
Collapse
|
12
|
Wang L, Sibrian-Vazquez M, Escobedo JO, Wang J, Moore RG, Strongin RM. Spiroguanidine rhodamines as fluorogenic probes for lysophosphatidic acid. Chem Commun (Camb) 2015; 51:1697-700. [PMID: 25516957 PMCID: PMC4320994 DOI: 10.1039/c4cc08818b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Direct determination of total lysophosphatidic acid (LPA) was accomplished using newly developed spiroguanidines derived from rhodamine B as universal fluorogenic probes. Optimum conditions for the quantitative analysis of total LPA were investigated. The linear range for the determination of total LPA is up to 5 μM with a limit of detection of 0.512 μM.
Collapse
Affiliation(s)
- Lei Wang
- Department of Chemistry, Portland State University, Portland, OR 97201, USA. Tel: +1-503-725-9724
| | - Martha Sibrian-Vazquez
- Department of Chemistry, Portland State University, Portland, OR 97201, USA. Tel: +1-503-725-9724
| | - Jorge O. Escobedo
- Department of Chemistry, Portland State University, Portland, OR 97201, USA. Tel: +1-503-725-9724
| | - Jialu Wang
- Department of Chemistry, Portland State University, Portland, OR 97201, USA. Tel: +1-503-725-9724
| | - Richard G. Moore
- Women and Infants Hospital, Brown University, 101 Dudley Street, Providence, RI 02905, USA; Tel: +1-401-453-7520
| | - Robert M. Strongin
- Department of Chemistry, Portland State University, Portland, OR 97201, USA. Tel: +1-503-725-9724
| |
Collapse
|
13
|
Santhosh PB, Kiryakova SI, Genova JL, Ulrih NP. Influence of iron oxide nanoparticles on bending elasticity and bilayer fluidity of phosphotidylcholine liposomal membranes. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.02.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
14
|
Hurjui I, Neamtu A, Dorohoi DO. Computational and spectral studies of 1,6-diphenyl-1,3,5-hexatriene (DPH) multicomponent solutions. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 115:382-387. [PMID: 23867641 DOI: 10.1016/j.saa.2013.06.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 06/03/2013] [Accepted: 06/05/2013] [Indexed: 06/02/2023]
Abstract
The multicomponent 1,6-diphenyl-1,3,5-hexatriene+tetrahydrofuran+water+ethanol (DPH+THF+W+E) solutions with variable content in water were studied by computational and spectral means. The computational results that indicate micelle formation in multicomponent solutions at high water content were correlated by the independence of the wavenumber in the maximum of the fluorescence on the solvent composition.
Collapse
Affiliation(s)
- Ion Hurjui
- Biophysical and Medical Physics Dept., Faculty of Medicine, Gr. T. Popa University, 16 University Street, Iasi 700115, Romania
| | | | | |
Collapse
|