1
|
Shigematsu T, Koshiyama K. Changes in free energy barrier for water permeation by stretch-induced phase transitions in phospholipid/cholesterol bilayers. J Biomol Struct Dyn 2024; 42:9159-9166. [PMID: 37656194 DOI: 10.1080/07391102.2023.2250447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 08/14/2023] [Indexed: 09/02/2023]
Abstract
Water permeation through phospholipid/cholesterol bilayers is the key to understanding tension-induced rupture of biological cell membranes. We performed molecular dynamics simulations of stretched phospholipid/cholesterol bilayers to investigate changes in the free energy profile of water molecules across the bilayer and the lipid structure responsible for water permeation. We modeled stretching of the bilayer by applying areal strain. In stretched phospholipid/cholesterol bilayers, the hydrophobic tail of the phospholipids became disordered and the free energy barrier to water permeation decreased. Upon exceeding the critical areal strain, a phase transition to an interdigitated gel phase occurred before rupture, and the hydrophobic tail ordering as well as the free energy barrier were restored. In pure phospholipid bilayers, we did not observe such recoveries. These transient recoveries in the phospholipid/cholesterol bilayer suppressed water permeation and membrane rupture, followed by an increase in the critical areal strain at which the bilayer ruptured. This result agrees with experimental results and provides a reasonable molecular mechanism for the toughness of phospholipid/cholesterol bilayers under tension.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Taiki Shigematsu
- Department of Mechanical Science & Bioengineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, Japan
| | - Kenichiro Koshiyama
- Graduate School of Technology, Industrial and Social Sciences, Tokushima University, Tokushima, Japan
| |
Collapse
|
2
|
Krogman WL, Woodard T, McKay RSF. Anesthetic Mechanisms: Synergistic Interactions With Lipid Rafts and Voltage-Gated Sodium Channels. Anesth Analg 2024; 139:92-106. [PMID: 37968836 DOI: 10.1213/ane.0000000000006738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
Despite successfully utilizing anesthetics for over 150 years, the mechanism of action remains relatively unknown. Recent studies have shown promising results, but due to the complex interactions between anesthetics and their targets, there remains a clear need for further mechanistic research. We know that lipophilicity is directly connected to anesthetic potency since lipid solubility relates to anesthetic partition into the membrane. However, clinically relevant concentrations of anesthetics do not significantly affect lipid bilayers but continue to influence various molecular targets. Lipid rafts are derived from liquid-ordered phases of the plasma membrane that contain increased concentrations of cholesterol and sphingomyelin and act as staging platforms for membrane proteins, including ion channels. Although anesthetics do not perturb membranes at clinically relevant concentrations, they have recently been shown to target lipid rafts. In this review, we summarize current research on how different types of anesthetics-local, inhalational, and intravenous-bind and affect both lipid rafts and voltage-gated sodium channels, one of their major targets, and how those effects synergize to cause anesthesia and analgesia. Local anesthetics block voltage-gated sodium channel pores while also disrupting lipid packing in ordered membranes. Inhalational anesthetics bind to the channel pore and the voltage-sensing domain while causing an increase in the number, size, and diameter of lipid rafts. Intravenous anesthetics bind to the channel primarily at the voltage-sensing domain and the selectivity filter, while causing lipid raft perturbation. These changes in lipid nanodomain structure possibly give proteins access to substrates that have translocated as a result of these structural alterations, resulting in lipid-driven anesthesia. Overall, anesthetics can impact channel activity either through direct interaction with the channel, indirectly through the lipid raft, or both. Together, these result in decreased sodium ion flux into the cell, disrupting action potentials and producing anesthetic effects. However, more research is needed to elucidate the indirect mechanisms associated with channel disruption through the lipid raft, as not much is known about anionic lipid products and their influence over voltage-gated sodium channels. Anesthetics' effect on S-palmitoylation, a promising mechanism for direct and indirect influence over voltage-gated sodium channels, is another auspicious avenue of research. Understanding the mechanisms of different types of anesthetics will allow anesthesiologists greater flexibility and more specificity when treating patients.
Collapse
Affiliation(s)
- William L Krogman
- From the Department of Anesthesiology, University of Kansas School of Medicine - Wichita, Wichita, Kansas
| | | | | |
Collapse
|
3
|
Pašalić L, Maleš P, Čikoš A, Pem B, Bakarić D. The rise of FTIR spectroscopy in the characterization of asymmetric lipid membranes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 305:123488. [PMID: 37813090 DOI: 10.1016/j.saa.2023.123488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/11/2023] [Accepted: 10/02/2023] [Indexed: 10/11/2023]
Abstract
In contrast to symmetric unilamellar liposomes (sLUVs) prepared from a mixture of different lipids, asymmetric ones (aLUVs) with different lipid composition in the inner and outer membrane leaflets are more suitable model systems of eukaryotic plasma membranes. However, apart from the challenging preparation of asymmetric liposomes and small amounts of obtained asymmetric unilamellar liposomes (aLUVs), a major drawback is the qualitative characterization of asymmetry, as each of the techniques used so far has certain limitations. In this regard, we prepared aLUVs composed dominantly of DPPC(out)/DPPS(in) lipids and, along with 1H NMR and DSC characterization, we showed for the first time how FTIR spectroscopy can be used in the presence of (a)symmetry between DPPC/DPPS lipid bilayers. Using second derivative FTIR spectra we demonstrated not only that the hydration of lipids glycerol backbone and choline moiety of DPPC differs in s/aLUVs, but in addition that the lateral interactions between hydrocarbon chains during the phase change display different trend in s/aLUVs. Molecular dynamics simulations confirmed different chain ordering and packing between s/a bilayers, with a significant influence of temperature, i.e. membrane phase.
Collapse
Affiliation(s)
- Lea Pašalić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Petra Maleš
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Ana Čikoš
- The Centre for Nuclear Magnetic Resonance (NMR), Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Barbara Pem
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| |
Collapse
|
4
|
Nandakumar A, Ito Y, Ueda M. Peptide-lipid hybrid vesicles with stimuli-responsive phase separation for controlled membrane functions. Chem Commun (Camb) 2023; 59:10644-10647. [PMID: 37580993 DOI: 10.1039/d3cc02954a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
A disulfide-tethered peptide-lipid conjugate self-assembled into a homogeneously distributed peptide-lipid hybrid vesicle. Upon dithiothreitol treatment, the homogeneous peptide-lipid membrane spontaneously divided into lipid-rich and peptide-rich domains, while the vesicle retained its size and shape. Membrane phase separation enhanced temperature-dependent cargo release.
Collapse
Affiliation(s)
- Avanashiappan Nandakumar
- Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
| | - Yoshihiro Ito
- Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Motoki Ueda
- Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| |
Collapse
|
5
|
Maleš P, Butumović M, Erceg I, Brkljača Z, Bakarić D. Influence of DPPE surface undulations on melting temperature determination: UV/Vis spectroscopic and MD study. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184072. [PMID: 36216096 DOI: 10.1016/j.bbamem.2022.184072] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 09/09/2022] [Accepted: 10/04/2022] [Indexed: 11/13/2022]
Abstract
One of the most distinguished quantities that describes lipid main phase transition, i.e. the transition from the gel (Lβ(')) to the fluid (Lα) phase, is its melting temperature (Tm). Because melting is accompanied by a large change in enthalpy the, Lβ(') → Lα transition can be monitored by various calorimetric, structural and spectroscopic techniques and Tm should be the same regardless of the metric monitored or the technique employed. However, in the case of DPPE multilamellar aggregates there is a small but systematic deviation of Tm values determined by DSC and FTIR spectroscopy. The aim of this paper is to explain this discrepancy by combined UV/Vis spectroscopic and MD computational approach. Multivariate analysis performed on temperature-dependent UV/Vis spectra of DPPE suspensions demonstrated that at 55 ± 1 °C certain phenomenon causes a small but detectable change in suspension turbidity, whereas a dominant change in the latter is registered at 63.2 ± 0.4 °C that coincides with Tm value determined from DSC curve. If this effect should be ignored, the overall data give Tm value the same as FTIR spectra data (61.0 ± 0.4 °C). As the classical MD simulations suggest that about 10° below Tm certain undulations appear at the surface of DPPE bilayers, we concluded that certain discontinuities in curvature fluctuations arise at reported temperature which are to some extent coupled with lipid melting. Ultimately, such events and the associated changes in curvature affect Tm value measured by different techniques.
Collapse
Affiliation(s)
- Petra Maleš
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Marija Butumović
- Division of Analytical Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia
| | - Ina Erceg
- Division for Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Zlatko Brkljača
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| |
Collapse
|
6
|
Boafo GF, Magar KT, Ekpo MD, Qian W, Tan S, Chen C. The Role of Cryoprotective Agents in Liposome Stabilization and Preservation. Int J Mol Sci 2022; 23:ijms232012487. [PMID: 36293340 PMCID: PMC9603853 DOI: 10.3390/ijms232012487] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/22/2022] [Accepted: 10/15/2022] [Indexed: 11/18/2022] Open
Abstract
To improve liposomes’ usage as drug delivery vehicles, cryoprotectants can be utilized to prevent constituent leakage and liposome instability. Cryoprotective agents (CPAs) or cryoprotectants can protect liposomes from the mechanical stress of ice by vitrifying at a specific temperature, which forms a glassy matrix. The majority of studies on cryoprotectants demonstrate that as the concentration of the cryoprotectant is increased, the liposomal stability improves, resulting in decreased aggregation. The effectiveness of CPAs in maintaining liposome stability in the aqueous state essentially depends on a complex interaction between protectants and bilayer composition. Furthermore, different types of CPAs have distinct effective mechanisms of action; therefore, the combination of several cryoprotectants may be beneficial and novel attributed to the synergistic actions of the CPAs. In this review, we discuss the use of liposomes as drug delivery vehicles, phospholipid–CPA interactions, their thermotropic behavior during freezing, types of CPA and their mechanism for preventing leakage of drugs from liposomes.
Collapse
Affiliation(s)
- George Frimpong Boafo
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, China
| | - Kosheli Thapa Magar
- Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Marlene Davis Ekpo
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, China
| | - Wang Qian
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, China
| | - Songwen Tan
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, China
- Correspondence: (S.T.); (C.C.)
| | - Chuanpin Chen
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, China
- Correspondence: (S.T.); (C.C.)
| |
Collapse
|
7
|
Maleš P, Pem B, Petrov D, Jurašin DD, Bakarić D. Deciphering the origin of the melting profile of unilamellar phosphatidylcholine liposomes by measuring the turbidity of its suspensions. SOFT MATTER 2022; 18:6703-6715. [PMID: 36017811 DOI: 10.1039/d2sm00878e] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The elucidation of the thermal properties of phosphatidylcholine liposomes is often based on the analysis of the thermal capacity profiles of multilamellar liposomes (MLV), which may qualitatively disagree with those of unilamellar liposomes (LUV). Experiments and interpretation of LUV liposomes is further complicated by aggregation and lamellarization of lipid bilayers in a short time period, which makes it almost impossible to distinguish the signatures of the two types of bilayers. To characterize independently MLV and LUV of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), the latter were prepared with the addition of small amounts of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylglycerol (DPPG) which, due to the sterical hindrance and negative charge at a given pH value, cause LUV repellence and contribute to their stability. Differential scanning calorimetry curves and temperature-dependent UV/Vis spectra of the prepared MLV and LUV were measured. Multivariate analysis of spectrophotometric data determined the phase transition temperatures (pretransition at Tp and the main phase transition at Tm), and based on the changes in turbidities, the thickness of the lipid bilayer in LUV was determined. The obtained data suggested that the curvature change is a key distinguishing factor in MLV and LUV heat capacity profiles. By combining the experimental results and those obtained by MD simulations, the interfacial water layer was characterized and its contribution to the thermal properties of LUV was discussed.
Collapse
Affiliation(s)
- Petra Maleš
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| | - Barbara Pem
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| | - Dražen Petrov
- Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences, 1180 Vienna, Austria
| | - Darija Domazet Jurašin
- Division for Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
| |
Collapse
|
8
|
Heimburg T. The thermodynamic soliton theory of the nervous impulse and possible medical implications. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 173:24-35. [PMID: 35640761 DOI: 10.1016/j.pbiomolbio.2022.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 05/05/2022] [Accepted: 05/22/2022] [Indexed: 06/15/2023]
Abstract
The textbook picture of nerve activity is that of a propagating voltage pulse driven by electrical currents through ion channel proteins, which are gated by changes in voltage, temperature, pressure or by drugs. All function is directly attributed to single molecules. We show that this leaves out many important thermodynamic couplings between different variables. A more recent alternative picture for the nerve pulse is of thermodynamic nature. It considers the nerve pulse as a soliton, i.e., a macroscopic excited region with properties that are influenced by thermodynamic variables including voltage, temperature, pressure and chemical potentials of membrane components. All thermodynamic variables are strictly coupled. We discuss the consequences for medical treatment in a view where one can compensate a maladjustment of one variable by adjusting another variable. For instance, one can explain why anesthesia can be counteracted by hydrostatic pressure and decrease in pH, suggest reasons why lithium over-dose may lead to tremor, and how tremor is related to alcohol intoxication. Lithium action as well as the effect of ethanol and the anesthetic ketamine in bipolar patients may fall in similar thermodynamic patterns. Such couplings remain obscure in a purely molecular picture. Other fields of application are the response of nerve activity to muscle stretching and the possibility of neural stimulation by ultrasound.
Collapse
Affiliation(s)
- T Heimburg
- Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100, Copenhagen Ø, Denmark.
| |
Collapse
|
9
|
Ion permeation across the membrane: A comprehensive comparison analysis on passive permeations of differently charged ions. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
10
|
MacDermott-Opeskin HI, Panizza A, Eijkelkamp BA, O'Mara ML. Dynamics of the Acinetobacter baumannii inner membrane under exogenous polyunsaturated fatty acid stress. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183908. [PMID: 35276227 DOI: 10.1016/j.bbamem.2022.183908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 02/11/2022] [Accepted: 03/05/2022] [Indexed: 01/04/2023]
Abstract
Exogenous polyunsaturated fatty acids (PUFAs) are readily incorporated into the synthesis pathways of A. baumannii membrane phospholipids, where they contribute to reduced bacterial fitness and increased antimicrobial susceptibility. Here we examine the impact of PUFA membrane modification on membrane organisation and biophysical properties using coarse grained MARTINI simulations of chemically representative membrane models developed from mass-spectrometry datasets of an untreated, arachidonic acid (AA) treated and docosahexaenoic acid (DHA) treated A. baumannii membranes. Enzymatic integration of AA or DHA into phospholipids of the A. baumannii membrane resulted in modulation of membrane biophysical properties. Membrane thickness decreased slightly following PUFA treatment, concomitant with changes in the lateral area per lipid of each lipid headgroup class. PUFA treatment resulted in a decrease in membrane ordering and an increase in lipid lateral diffusion. Changes in lateral membrane organisation were observed in the PUFA treated membranes, with a concurrent increase in ordered cardiolipin domains and disordered PUFA-containing domains. Notably, separation between ordered and disordered domains was enhanced and was more pronounced for DHA relative to AA, providing a possible mechanism for greater antimicrobial action of DHA relative to AA observed experimentally. Furthermore, the membrane active antimicrobial, pentamidine, preferentially adsorbs to cardiolipin domains of the A. baumannii model membranes. This interaction, and membrane penetration of pentamidine, was enhanced following PUFA treatment. Cumulatively, this work explores the wide-ranging effects of PUFA incorporation on the A. baumannii membrane and provides a molecular basis for bacterial inner membrane disruption by PUFAs.
Collapse
Affiliation(s)
- Hugo I MacDermott-Opeskin
- Research School of Chemistry, College of Science, Australian National University, Canberra, ACT, 2601, Australia
| | - Alessandra Panizza
- Research School of Chemistry, College of Science, Australian National University, Canberra, ACT, 2601, Australia
| | - Bart A Eijkelkamp
- Molecular Science and Technology, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Megan L O'Mara
- Research School of Chemistry, College of Science, Australian National University, Canberra, ACT, 2601, Australia.
| |
Collapse
|
11
|
Canepa E, Relini A, Bochicchio D, Lavagna E, Mescola A. Amphiphilic Gold Nanoparticles: A Biomimetic Tool to Gain Mechanistic Insights into Peptide-Lipid Interactions. MEMBRANES 2022; 12:673. [PMID: 35877876 PMCID: PMC9324301 DOI: 10.3390/membranes12070673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/20/2022] [Accepted: 06/22/2022] [Indexed: 02/04/2023]
Abstract
Functional peptides are now widely used in a myriad of biomedical and clinical contexts, from cancer therapy and tumor targeting to the treatment of bacterial and viral infections. Underlying this diverse range of applications are the non-specific interactions that can occur between peptides and cell membranes, which, in many contexts, result in spontaneous internalization of the peptide within cells by avoiding energy-driven endocytosis. For this to occur, the amphipathicity and surface structural flexibility of the peptides play a crucial role and can be regulated by the presence of specific molecular residues that give rise to precise molecular events. Nevertheless, most of the mechanistic details regulating the encounter between peptides and the membranes of bacterial or animal cells are still poorly understood, thus greatly limiting the biomimetic potential of these therapeutic molecules. In this arena, finely engineered nanomaterials-such as small amphiphilic gold nanoparticles (AuNPs) protected by a mixed thiol monolayer-can provide a powerful tool for mimicking and investigating the physicochemical processes underlying peptide-lipid interactions. Within this perspective, we present here a critical review of membrane effects induced by both amphiphilic AuNPs and well-known amphiphilic peptide families, such as cell-penetrating peptides and antimicrobial peptides. Our discussion is focused particularly on the effects provoked on widely studied model cell membranes, such as supported lipid bilayers and lipid vesicles. Remarkable similarities in the peptide or nanoparticle membrane behavior are critically analyzed. Overall, our work provides an overview of the use of amphiphilic AuNPs as a highly promising tailor-made model to decipher the molecular events behind non-specific peptide-lipid interactions and highlights the main affinities observed both theoretically and experimentally. The knowledge resulting from this biomimetic approach could pave the way for the design of synthetic peptides with tailored functionalities for next-generation biomedical applications, such as highly efficient intracellular delivery systems.
Collapse
Affiliation(s)
- Ester Canepa
- Department of Physics, University of Genoa, Via Dodecaneso 33, 16146 Genoa, Italy; (E.C.); (A.R.); (D.B.)
| | - Annalisa Relini
- Department of Physics, University of Genoa, Via Dodecaneso 33, 16146 Genoa, Italy; (E.C.); (A.R.); (D.B.)
| | - Davide Bochicchio
- Department of Physics, University of Genoa, Via Dodecaneso 33, 16146 Genoa, Italy; (E.C.); (A.R.); (D.B.)
| | - Enrico Lavagna
- Department of Physics, University of Genoa, Via Dodecaneso 33, 16146 Genoa, Italy; (E.C.); (A.R.); (D.B.)
| | - Andrea Mescola
- CNR-Nanoscience Institute-S3, Via Campi 213/A, 41125 Modena, Italy
| |
Collapse
|
12
|
Murata M, Matsumori N, Kinoshita M, London E. Molecular substructure of the liquid-ordered phase formed by sphingomyelin and cholesterol: sphingomyelin clusters forming nano-subdomains are a characteristic feature. Biophys Rev 2022; 14:655-678. [PMID: 35791389 DOI: 10.1007/s12551-022-00967-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 05/26/2022] [Indexed: 11/29/2022] Open
Abstract
As a model of lipid rafts, the liquid-ordered (Lo) phase formed by sphingomyelin (SM) and cholesterol (Cho) in bilayer membranes has long attracted the attention of biophysics researchers. New approaches and methodologies have led to a better understanding of the molecular basis of the Lo domain structure. This review summarizes studies on model membrane systems consisting of SM/unsaturated phospholipid/Cho implying that the Lo phase contains SM-based nanodomains (or nano-subdomains). Some of the Lo phase properties may be attributed to these nanodomains. Several studies suggest that the nanodomains contain clustered SM molecules packed densely to form gel-phase-like subdomains of single-digit nanometer size at physiological temperatures. Cho and unsaturated lipids located in the Lo phase are likely to be concentrated at the boundaries between the subdomains. These subdomains are not readily detected in the Lo phase formed by saturated phosphatidylcholine (PC) molecules, suggesting that they are strongly stabilized by homophilic interactions specific to SM, e.g., between SM amide groups. This model for the Lo phase is supported by experiments using dihydro-SM, which is thought to have stronger homophilic interactions than SM, as well as by studies using the enantiomer of SM having opposite stereochemistry to SM at the 2 and 3 positions and by some molecular dynamics (MD) simulations of lipid bilayers containing Lo-lipids. Nanosized gel subdomains seem to play an important role in controlling membrane organization and function in biological membranes.
Collapse
Affiliation(s)
- Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, Osaka, 560-0043 Japan.,ERATO, Lipid Active Structure Project, Japan Science and Technology Agency, Graduate School of Science, Osaka University, Osaka, 560-0043 Japan
| | - Nobuaki Matsumori
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395 Japan
| | - Masanao Kinoshita
- ERATO, Lipid Active Structure Project, Japan Science and Technology Agency, Graduate School of Science, Osaka University, Osaka, 560-0043 Japan.,Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395 Japan
| | - Erwin London
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215 USA
| |
Collapse
|
13
|
Maleš P, Brkljača Z, Domazet Jurašin D, Bakarić D. New spirit of an old technique: Characterization of lipid phase transitions via UV/Vis spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 272:121013. [PMID: 35176647 DOI: 10.1016/j.saa.2022.121013] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/26/2022] [Accepted: 02/04/2022] [Indexed: 06/14/2023]
Abstract
One of the advantages of investigating lipid phase transitions by thermoanalytical techniques such as DSC is manifested in the proportionality of the signal strength on a DSC curve, attributed to a particular thermotropic event, and its cooperativity degree. Accordingly, the pretransition of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) is less noticeable than its main phase transition; as a matter of fact, when DSC measurements are performed at low heating rate, such low-cooperativity phase transition could go (almost) unnoticed. The aim of this work is to present temperature-dependent UV/Vis spectroscopy, based on a temperature-dependent change in DPPC suspension turbidity, as a technique applicable for determination of lipid phase transition temperatures. Multivariate analyzes of the acquired UV/Vis spectra show that phase transitions of the low-cooperativity degree, such as pretransitions, can be identified with the same certainty as transitions of a high-cooperativity degree.
Collapse
Affiliation(s)
- Petra Maleš
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Zlatko Brkljača
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Darija Domazet Jurašin
- Division for Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Danijela Bakarić
- Division for Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia.
| |
Collapse
|
14
|
Frallicciardi J, Melcr J, Siginou P, Marrink SJ, Poolman B. Membrane thickness, lipid phase and sterol type are determining factors in the permeability of membranes to small solutes. Nat Commun 2022; 13:1605. [PMID: 35338137 PMCID: PMC8956743 DOI: 10.1038/s41467-022-29272-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 03/02/2022] [Indexed: 12/16/2022] Open
Abstract
Cell membranes provide a selective semi-permeable barrier to the passive transport of molecules. This property differs greatly between organisms. While the cytoplasmic membrane of bacterial cells is highly permeable for weak acids and glycerol, yeasts can maintain large concentration gradients. Here we show that such differences can arise from the physical state of the plasma membrane. By combining stopped-flow kinetic measurements with molecular dynamics simulations, we performed a systematic analysis of the permeability of a variety of small molecules through synthetic membranes of different lipid composition to obtain detailed molecular insight into the permeation mechanisms. While membrane thickness is an important parameter for the permeability through fluid membranes, the largest differences occur when the membranes transit from the liquid-disordered to liquid-ordered and/or to gel state, which is in agreement with previous work on passive diffusion of water. By comparing our results with in vivo measurements from yeast, we conclude that the yeast membrane exists in a highly ordered and rigid state, which is comparable to synthetic saturated DPPC-sterol membranes. Membrane permeability of small molecules depends on the composition of the lipid bilayer. Here, authors compare permeability measured on membranes in different physical states and conclude that the yeast membrane exists in a highly ordered phase.
Collapse
Affiliation(s)
- Jacopo Frallicciardi
- Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, the Netherlands
| | - Josef Melcr
- Department of Biophysical Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, the Netherlands
| | - Pareskevi Siginou
- Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, the Netherlands
| | - Siewert J Marrink
- Department of Biophysical Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, the Netherlands.
| | - Bert Poolman
- Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, the Netherlands.
| |
Collapse
|
15
|
Gohrbandt M, Lipski A, Grimshaw JW, Buttress JA, Baig Z, Herkenhoff B, Walter S, Kurre R, Deckers‐Hebestreit G, Strahl H. Low membrane fluidity triggers lipid phase separation and protein segregation in living bacteria. EMBO J 2022; 41:e109800. [PMID: 35037270 PMCID: PMC8886542 DOI: 10.15252/embj.2021109800] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/19/2021] [Accepted: 12/21/2021] [Indexed: 11/09/2022] Open
Abstract
All living organisms adapt their membrane lipid composition in response to changes in their environment or diet. These conserved membrane-adaptive processes have been studied extensively. However, key concepts of membrane biology linked to regulation of lipid composition including homeoviscous adaptation maintaining stable levels of membrane fluidity, and gel-fluid phase separation resulting in domain formation, heavily rely upon in vitro studies with model membranes or lipid extracts. Using the bacterial model organisms Escherichia coli and Bacillus subtilis, we now show that inadequate in vivo membrane fluidity interferes with essential complex cellular processes including cytokinesis, envelope expansion, chromosome replication/segregation and maintenance of membrane potential. Furthermore, we demonstrate that very low membrane fluidity is indeed capable of triggering large-scale lipid phase separation and protein segregation in intact, protein-crowded membranes of living cells; a process that coincides with the minimal level of fluidity capable of supporting growth. Importantly, the in vivo lipid phase separation is not associated with a breakdown of the membrane diffusion barrier function, thus explaining why the phase separation process induced by low fluidity is biologically reversible.
Collapse
Affiliation(s)
- Marvin Gohrbandt
- Mikrobiologie, Fachbereich Biologie/ChemieUniversität OsnabrückOsnabrückGermany
| | - André Lipski
- Lebensmittelmikrobiologie und ‐hygieneInstitut für Ernährungs‐ und LebensmittelwissenschaftenRheinische Friedrich‐Wilhelms‐Universität BonnBonnGermany
| | - James W Grimshaw
- Centre for Bacterial Cell BiologyBiosciences InstituteFaculty of Medical SciencesNewcastle UniversityNewcastle upon TyneUK
| | - Jessica A Buttress
- Centre for Bacterial Cell BiologyBiosciences InstituteFaculty of Medical SciencesNewcastle UniversityNewcastle upon TyneUK
| | - Zunera Baig
- Centre for Bacterial Cell BiologyBiosciences InstituteFaculty of Medical SciencesNewcastle UniversityNewcastle upon TyneUK
| | - Brigitte Herkenhoff
- Mikrobiologie, Fachbereich Biologie/ChemieUniversität OsnabrückOsnabrückGermany
| | - Stefan Walter
- Mikrobiologie, Fachbereich Biologie/ChemieUniversität OsnabrückOsnabrückGermany
| | - Rainer Kurre
- Center of Cellular NanoanalyticsIntegrated Bioimaging FacilityUniversität OsnabrückOsnabrückGermany
| | | | - Henrik Strahl
- Centre for Bacterial Cell BiologyBiosciences InstituteFaculty of Medical SciencesNewcastle UniversityNewcastle upon TyneUK
| |
Collapse
|
16
|
Laroussi M, Bekeschus S, Keidar M, Bogaerts A, Fridman A, Lu XP, Ostrikov KK, Hori M, Stapelmann K, Miller V, Reuter S, Laux C, Mesbah A, Walsh J, Jiang C, Thagard SM, Tanaka H, Liu DW, Yan D, Yusupov M. Low Temperature Plasma for Biology, Hygiene, and Medicine: Perspective and Roadmap. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2022. [DOI: 10.1109/trpms.2021.3135118] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
17
|
Schlarmann P, Ikeda A, Funato K. Membrane Contact Sites in Yeast: Control Hubs of Sphingolipid Homeostasis. MEMBRANES 2021; 11:971. [PMID: 34940472 PMCID: PMC8707754 DOI: 10.3390/membranes11120971] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 01/02/2023]
Abstract
Sphingolipids are the most diverse class of membrane lipids, in terms of their structure and function. Structurally simple sphingolipid precursors, such as ceramides, act as intracellular signaling molecules in various processes, including apoptosis, whereas mature and complex forms of sphingolipids are important structural components of the plasma membrane. Supplying complex sphingolipids to the plasma membrane, according to need, while keeping pro-apoptotic ceramides in check is an intricate task for the cell and requires mechanisms that tightly control sphingolipid synthesis, breakdown, and storage. As each of these processes takes place in different organelles, recent studies, using the budding yeast Saccharomyces cerevisiae, have investigated the role of membrane contact sites as hubs that integrate inter-organellar sphingolipid transport and regulation. In this review, we provide a detailed overview of the findings of these studies and put them into the context of established regulatory mechanisms of sphingolipid homeostasis. We have focused on the role of membrane contact sites in sphingolipid metabolism and ceramide transport, as well as the mechanisms that prevent toxic ceramide accumulation.
Collapse
Affiliation(s)
| | | | - Kouichi Funato
- Graduate School of Integrated Sciences for Life, Hiroshima University, Kagamiyama 1-4-4, Higashi-Hiroshima 739-8528, Japan; (P.S.); (A.I.)
| |
Collapse
|
18
|
Lucchino M, Billet A, Bai S, Dransart E, Hadjerci J, Schmidt F, Wunder C, Johannes L. Absolute Quantification of Drug Vector Delivery to the Cytosol. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Marco Lucchino
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| | - Anne Billet
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
- Université de Paris 85 boulevard Saint-Germain 75006 Paris France
| | - Siau‐Kun Bai
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| | - Estelle Dransart
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| | - Justine Hadjerci
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| | - Frédéric Schmidt
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| | - Christian Wunder
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| | - Ludger Johannes
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie— Université PSL 26 rue d'Ulm 75248 Paris Cedex 05 France
| |
Collapse
|
19
|
Lucchino M, Billet A, Bai S, Dransart E, Hadjerci J, Schmidt F, Wunder C, Johannes L. Absolute Quantification of Drug Vector Delivery to the Cytosol. Angew Chem Int Ed Engl 2021; 60:14824-14830. [PMID: 33904231 PMCID: PMC8252025 DOI: 10.1002/anie.202102332] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/11/2021] [Indexed: 01/04/2023]
Abstract
Macromolecular drugs inefficiently cross membranes to reach their cytosolic targets. They require drug delivery vectors to facilitate their translocation across the plasma membrane or escape from endosomes. Optimization of these vectors has however been hindered by the difficulty to accurately measure cytosolic arrival. We have developed an exceptionally sensitive and robust assay for the relative or absolute quantification of this step. The assay is based on benzylguanine and biotin modifications on a drug delivery vector of interest, which allow, respectively, for selective covalent capture in the cytosol with a SNAP-tag fusion protein and for quantification at picomolar sensitivity. The assay was validated by determining the absolute numbers of cytosolic molecules for two drug delivery vectors: the B-subunit of Shiga toxin and the cell-penetrating peptide TAT. We expect this assay to favor delivery vector optimization and the understanding of the enigmatic translocation process.
Collapse
Affiliation(s)
- Marco Lucchino
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| | - Anne Billet
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
- Université de Paris85 boulevard Saint-Germain75006ParisFrance
| | - Siau‐Kun Bai
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| | - Estelle Dransart
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| | - Justine Hadjerci
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| | - Frédéric Schmidt
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| | - Christian Wunder
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| | - Ludger Johannes
- Cellular and Chemical Biology Unit, U1143 INSERM, UMR3666 CNRS, Institut Curie—Université PSL26 rue d'Ulm75248Paris Cedex 05France
| |
Collapse
|
20
|
Oliveira MC, Yusupov M, Bogaerts A, Cordeiro RM. Lipid Oxidation: Role of Membrane Phase-Separated Domains. J Chem Inf Model 2021; 61:2857-2868. [PMID: 34080860 DOI: 10.1021/acs.jcim.1c00104] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lipid oxidation is associated with several inflammatory and neurodegenerative diseases, but many questions to unravel its effects on biomembranes are still open due to the complexity of the topic. For instance, recent studies indicated that phase-separated domains can have a significant effect on membrane function. It is reported that domain interfaces are "hot spots" for pore formation, but the underlying mechanisms and the effect of oxidation-induced phase separation on membranes remain elusive. Thus, to evaluate the permeability of the membrane coexisting of liquid-ordered (Lo) and liquid-disordered (Ld) domains, we performed atomistic molecular dynamics simulations. Specifically, we studied the membrane permeability of nonoxidized or oxidized homogeneous membranes (single-phase) and at the Lo/Ld domain interfaces of heterogeneous membranes, where the Ld domain is composed of either oxidized or nonoxidized lipids. Our simulation results reveal that the addition of only 1.5% of lipid aldehyde molecules at the Lo/Ld domain interfaces of heterogeneous membranes increases the membrane permeability, whereas their addition at homogeneous membranes does not have any effect. This study is of interest for a better understanding of cancer treatment methods based on oxidative stress (causing among others lipid oxidation), such as plasma medicine and photodynamic therapy.
Collapse
Affiliation(s)
- Maria C Oliveira
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Avenida dos Estados 5001, CEP 09210-580 Santo André, SP, Brazil.,Research Group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Maksudbek Yusupov
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Annemie Bogaerts
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Rodrigo M Cordeiro
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Avenida dos Estados 5001, CEP 09210-580 Santo André, SP, Brazil
| |
Collapse
|
21
|
Mioka T, Guo T, Wang S, Tsuji T, Kishimoto T, Fujimoto T, Tanaka K. Characterization of micron-scale protein-depleted plasma membrane domains in phosphatidylserine-deficient yeast cells. J Cell Sci 2021; 135:261783. [PMID: 34000034 DOI: 10.1242/jcs.256529] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/16/2021] [Indexed: 12/30/2022] Open
Abstract
Membrane phase separation to form micron-scale domains of lipids and proteins occurs in artificial membranes; however, a similar large-scale phase separation has not been reported in the plasma membrane of the living cells. We show here that a stable micron-scale protein-depleted region is generated in the plasma membrane of yeast mutants lacking phosphatidylserine at high temperatures. We named this region the 'void zone'. Transmembrane proteins and certain peripheral membrane proteins and phospholipids are excluded from the void zone. The void zone is rich in ergosterol, and requires ergosterol and sphingolipids for its formation. Such properties are also found in the cholesterol-enriched domains of phase-separated artificial membranes, but the void zone is a novel membrane domain that requires energy and various cellular functions for its formation. The formation of the void zone indicates that the plasma membrane in living cells has the potential to undergo phase separation with certain lipid compositions. We also found that void zones were frequently in contact with vacuoles, in which a membrane domain was also formed at the contact site.
Collapse
Affiliation(s)
- Tetsuo Mioka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Tian Guo
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Shiyao Wang
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Takuma Tsuji
- Laboratory of Molecular Cell Biology, Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Takuma Kishimoto
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| | - Toyoshi Fujimoto
- Laboratory of Molecular Cell Biology, Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Kazuma Tanaka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo, Hokkaido 060-0815, Japan
| |
Collapse
|
22
|
Water Pores in Planar Lipid Bilayers at Fast and Slow Rise of Transmembrane Voltage. MEMBRANES 2021; 11:membranes11040263. [PMID: 33916447 PMCID: PMC8067013 DOI: 10.3390/membranes11040263] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022]
Abstract
Basic understanding of the barrier properties of biological membranes can be obtained by studying model systems, such as planar lipid bilayers. Here, we study water pores in planar lipid bilayers in the presence of transmembrane voltage. Planar lipid bilayers were exposed to fast and slow linearly increasing voltage and current signals. We measured the capacitance, breakdown voltage, and rupture time of planar lipid bilayers composed of 1-pamitoyl 2-oleoyl phosphatidylcholine (POPC), 1-pamitoyl 2-oleoyl phosphatidylserine (POPS), and a mixture of both lipids in a 1:1 ratio. Based on the measurements, we evaluated the change in the capacitance of the planar lipid bilayer corresponding to water pores, the radius of water pores at membrane rupture, and the fraction of the area of the planar lipid bilayer occupied by water pores.planar lipid bilayer capacitance, which corresponds to water pores, water pore radius at the membrane rupture, and a fraction of the planar lipid bilayer area occupied by water pores. The estimated pore radii determining the rupture of the planar lipid bilayer upon fast build-up of transmembrane voltage are 0.101 nm, 0.110 nm, and 0.106 nm for membranes composed of POPC, POPS, and POPC:POPS, respectively. The fraction of the surface occupied by water pores at the moment of rupture of the planar lipid bilayer The fraction of an area that is occupied by water pores at the moment of planar lipid bilayer rupture is in the range of 0.1–1.8%.
Collapse
|
23
|
Oliveira MC, Yusupov M, Bogaerts A, Cordeiro RM. How do nitrated lipids affect the properties of phospholipid membranes? Arch Biochem Biophys 2020; 695:108548. [DOI: 10.1016/j.abb.2020.108548] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/23/2020] [Accepted: 08/19/2020] [Indexed: 01/16/2023]
|
24
|
DiPasquale M, Nguyen MHL, Rickeard BW, Cesca N, Tannous C, Castillo SR, Katsaras J, Kelley EG, Heberle FA, Marquardt D. The antioxidant vitamin E as a membrane raft modulator: Tocopherols do not abolish lipid domains. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2020; 1862:183189. [PMID: 31954106 PMCID: PMC10443432 DOI: 10.1016/j.bbamem.2020.183189] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/07/2020] [Accepted: 01/09/2020] [Indexed: 01/06/2023]
Abstract
The antioxidant vitamin E is a commonly used vitamin supplement. Although the multi-billion dollar vitamin and nutritional supplement industry encourages the use of vitamin E, there is very little evidence supporting its actual health benefits. Moreover, vitamin E is now marketed as a lipid raft destabilizing anti-cancer agent, in addition to its antioxidant behaviour. Here, we studied the influence of vitamin E and some of its vitamers on membrane raft stability using phase separating unilamellar lipid vesicles in conjunction with small-angle scattering techniques and fluorescence microscopy. We find that lipid phase behaviour remains unperturbed well beyond physiological concentrations of vitamin E (up to a mole fraction of 0.10). Our results are consistent with a proposed line active role of vitamin E at the domain boundary. We discuss the implications of these findings as they pertain to lipid raft modification in native membranes, and propose a new hypothesis for the antioxidant mechanism of vitamin E.
Collapse
Affiliation(s)
- Mitchell DiPasquale
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada
| | - Michael H L Nguyen
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada
| | - Brett W Rickeard
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada
| | - Nicole Cesca
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada
| | - Christopher Tannous
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada
| | - Stuart R Castillo
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada
| | - John Katsaras
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Joint Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA
| | - Elizabeth G Kelley
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | | | - Drew Marquardt
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario,Canada; Department of Physics, University of Windsor, Windsor, Ontario, Canada.
| |
Collapse
|
25
|
Srivastava A, Debnath A. Asymmetry and Rippling in Mixed Surfactant Bilayers from All-Atom and Coarse-Grained Simulations: Interdigitation and Per Chain Entropy. J Phys Chem B 2020; 124:6420-6436. [DOI: 10.1021/acs.jpcb.0c03761] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Arpita Srivastava
- Department of Chemistry, IIT Jodhpur, Jodhpur 342037, Rajasthan, India
| | - Ananya Debnath
- Department of Chemistry, IIT Jodhpur, Jodhpur 342037, Rajasthan, India
| |
Collapse
|
26
|
Khmelinskaia A, Marquês JMT, Bastos AEP, Antunes CAC, Bento-Oliveira A, Scolari S, Lobo GMDS, Malhó R, Herrmann A, Marinho HS, de Almeida RFM. Liquid-Ordered Phase Formation by Mammalian and Yeast Sterols: A Common Feature With Organizational Differences. Front Cell Dev Biol 2020; 8:337. [PMID: 32596234 PMCID: PMC7304482 DOI: 10.3389/fcell.2020.00337] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/17/2020] [Indexed: 11/13/2022] Open
Abstract
Here, biophysical properties of membranes enriched in three metabolically related sterols are analyzed both in vitro and in vivo. Unlike cholesterol and ergosterol, the common metabolic precursor zymosterol is unable to induce the formation of a liquid ordered (l o) phase in model lipid membranes and can easily accommodate in a gel phase. As a result, Zym has a marginal ability to modulate the passive membrane permeability of lipid vesicles with different compositions, contrary to cholesterol and ergosterol. Using fluorescence-lifetime imaging microscopy of an aminostyryl dye in living mammalian and yeast cells we established a close parallel between sterol-dependent membrane biophysical properties in vivo and in vitro. This approach unraveled fundamental differences in yeast and mammalian plasma membrane organization. It is often suggested that, in eukaryotes, areas that are sterol-enriched are also rich in sphingolipids, constituting highly ordered membrane regions. Our results support that while cholesterol is able to interact with saturated lipids, ergosterol seems to interact preferentially with monounsaturated phosphatidylcholines. Taken together, we show that different eukaryotic kingdoms developed unique solutions for the formation of a sterol-rich plasma membrane, a common evolutionary trait that accounts for sterol structural diversity.
Collapse
Affiliation(s)
- Alena Khmelinskaia
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Joaquim M T Marquês
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - André E P Bastos
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Catarina A C Antunes
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Andreia Bento-Oliveira
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Silvia Scolari
- Department of Biology, Molecular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Gerson M da S Lobo
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Rui Malhó
- Faculdade de Ciências, BioISI, Universidade de Lisboa, Lisbon, Portugal
| | - Andreas Herrmann
- Department of Biology, Molecular Biophysics, Humboldt-Universität zu Berlin, Berlin, Germany
| | - H Susana Marinho
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Rodrigo F M de Almeida
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| |
Collapse
|
27
|
Stubbs C, Bailey TL, Murray K, Gibson MI. Polyampholytes as Emerging Macromolecular Cryoprotectants. Biomacromolecules 2020; 21:7-17. [PMID: 31418266 PMCID: PMC6960013 DOI: 10.1021/acs.biomac.9b01053] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/15/2019] [Indexed: 11/29/2022]
Abstract
Cellular cryopreservation is a platform technology which underpins cell biology, biochemistry, biomaterials, diagnostics, and the cold chain for emerging cell-based therapies. This technique relies on effective methods for banking and shipping to avoid the need for continuous cell culture. The most common method to achieve cryopreservation is to use large volumes of organic solvent cryoprotective agents which can promote either a vitreous (ice free) phase or dehydrate and protect the cells. These methods are very successful but are not perfect: not all cell types can be cryopreserved and recovered, and the cells do not always retain their phenotype and function post-thaw. This Perspective will introduce polyampholytes as emerging macromolecular cryoprotective agents and demonstrate they have the potential to impact a range of fields from cell-based therapies to basic cell biology and may be able to improve, or replace, current solvent-based cryoprotective agents. Polyampholytes have been shown to be remarkable (mammalian cell) cryopreservation enhancers, but their mechanism of action is unclear, which may include membrane protection, solvent replacement, or a yet unknown protective mechanism, but it seems the modulation of ice growth (recrystallization) may only play a minor role in their function, unlike other macromolecular cryoprotectants. This Perspective will discuss their synthesis and summarize the state-of-the-art, including hypotheses of how they function, to introduce this exciting area of biomacromolecular science.
Collapse
Affiliation(s)
- Christopher Stubbs
- Department
of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Trisha L. Bailey
- Department
of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Kathryn Murray
- Department
of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Matthew I. Gibson
- Department
of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
- Warwick
Medical School, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| |
Collapse
|
28
|
Ghysels A, Krämer A, Venable RM, Teague WE, Lyman E, Gawrisch K, Pastor RW. Permeability of membranes in the liquid ordered and liquid disordered phases. Nat Commun 2019; 10:5616. [PMID: 31819053 PMCID: PMC6901538 DOI: 10.1038/s41467-019-13432-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 11/06/2019] [Indexed: 11/09/2022] Open
Abstract
The functional significance of ordered nanodomains (or rafts) in cholesterol rich eukaryotic cell membranes has only begun to be explored. This study exploits the correspondence of cellular rafts and liquid ordered (Lo) phases of three-component lipid bilayers to examine permeability. Molecular dynamics simulations of Lo phase dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylcholine (DOPC), and cholesterol show that oxygen and water transit a leaflet through the DOPC and cholesterol rich boundaries of hexagonally packed DPPC microdomains, freely diffuse along the bilayer midplane, and escape the membrane along the boundary regions. Electron paramagnetic resonance experiments provide critical validation: the measured ratio of oxygen concentrations near the midplanes of liquid disordered (Ld) and Lo bilayers of DPPC/DOPC/cholesterol is 1.75 ± 0.35, in very good agreement with 1.3 ± 0.3 obtained from simulation. The results show how cellular rafts can be structurally rigid signaling platforms while remaining nearly as permeable to small molecules as the Ld phase.
Collapse
Affiliation(s)
- An Ghysels
- Center for Molecular Modeling, Ghent University, Technologiepark 46, 9052, Gent, Belgium.
| | - Andreas Krämer
- Laboratory of Computational Biology, National Heart Lung Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard M Venable
- Laboratory of Computational Biology, National Heart Lung Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Walter E Teague
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Edward Lyman
- Department of Physics and Astronomy and Department of Chemistry and Biochemistry, University of Delaware, Newark, 19716, DE, USA
| | - Klaus Gawrisch
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard W Pastor
- Laboratory of Computational Biology, National Heart Lung Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| |
Collapse
|
29
|
Stelter D, Keyes T. Simulation of fluid/gel phase equilibrium in lipid vesicles. SOFT MATTER 2019; 15:8102-8112. [PMID: 31588466 DOI: 10.1039/c9sm00854c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Simulation of single component dipalmitoylphosphatidylcholine (DPPC) coarse-grained DRY-MARTINI lipid vesicles of diameter 10 nm (1350 lipids), 20 nm (5100 lipids) and 40 nm (17 600 lipids) is performed using statistical temperature molecular dynamics (STMD), to study finite size effects upon the order-disorder gel/fluid transition. STMD obtains enhanced sampling using a generalized ensemble, obtaining a flat energy distribution between upper and lower cutoffs, with little computational cost over canonical molecular dynamics. A single STMD trajectory of moderate length is sufficient to sample 20+ transition events, without trapping in the gel phase, and obtain well averaged properties. Phase transitions are analyzed via the energy-dependence of the statistical temperature, TS(U). The transition temperature decreases with decreasing diameter, in agreement with experiment, and the transition changes from first order to borderline first-second order. The size- and layer-dependence of the structure of both stable phases, and of the pathway of the phase transition, are determined. It is argued that the finite size effects are primarily caused by the disruption of the gel packing by curvature. Inhomogeneous states with faceted gel patches connected by unusual fluid seams are observed at high curvature, with visually different structure in the inner and outer layers due to the different curvatures. Thus a simple physical picture describes phase transitions in nanoscale finite systems far from the thermodynamic limit.
Collapse
Affiliation(s)
- David Stelter
- Boston University, Chemistry Department, 590 Commonwealth Avenue, Boston, MA 02215, USA.
| | - Tom Keyes
- Boston University, Chemistry Department, 590 Commonwealth Avenue, Boston, MA 02215, USA.
| |
Collapse
|
30
|
Oliveira MC, Yusupov M, Bogaerts A, Cordeiro RM. Molecular dynamics simulations of mechanical stress on oxidized membranes. Biophys Chem 2019; 254:106266. [PMID: 31629220 DOI: 10.1016/j.bpc.2019.106266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 09/09/2019] [Accepted: 09/12/2019] [Indexed: 12/27/2022]
Abstract
Biomembranes are under constant attack of free radicals that may lead to lipid oxidation in conditions of oxidative stress. The products generated during lipid oxidation are responsible for structural and dynamical changes which may jeopardize the membrane function. For instance, the local rearrangements of oxidized lipid molecules may induce membrane rupture. In this study, we investigated the effects of mechanical stress on oxidized phospholipid bilayers (PLBs). Model bilayers were stretched until pore formation (or poration) using non-equilibrium molecular dynamics simulations. We studied single-component homogeneous membranes composed of lipid oxidation products, as well as two-component heterogeneous membranes with coexisting native and oxidized domains. In homogeneous membranes, the oxidation products with -OH and -OOH groups reduced the areal strain required for pore formation, whereas the oxidation product with O group behaved similarly to the native membrane. In heterogeneous membranes composed of oxidized and non-oxidized domains, we tested the hypothesis according to which poration may be facilitated at the domain interface region. However, results were inconclusive due to their large statistical variance and sensitivity to simulation setup parameters. We pointed out important technical issues that need to be considered in future simulations of mechanically-induced poration of heterogeneous membranes. This research is of interest for photodynamic therapy and plasma medicine, because ruptured and intact plasma membranes are experimentally considered hallmarks of necrotic and apoptotic cell death.
Collapse
Affiliation(s)
- Maria C Oliveira
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Avenida dos Estados 5001, CEP 09210-580 Santo André, SP, Brazil
| | - Maksudbek Yusupov
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Annemie Bogaerts
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Rodrigo M Cordeiro
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Avenida dos Estados 5001, CEP 09210-580 Santo André, SP, Brazil.
| |
Collapse
|
31
|
Ouchi Y, Unoura K, Nabika H. Role of Oxidized Lipids in Permeation of H 2O 2 Through a Lipid Membrane: Molecular Mechanism of an Inhibitor to Promoter Switch. Sci Rep 2019; 9:12497. [PMID: 31467337 PMCID: PMC6715804 DOI: 10.1038/s41598-019-48954-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/09/2019] [Indexed: 01/10/2023] Open
Abstract
H2O2 permeation through a cell membrane significantly affects living organisms, and permeation is controlled by the physico-chemical nature of lipids and other membrane components. We investigated the molecular relationship between H2O2 permeation and lipid membrane structure using three oxidized lipids. POVPC and PazePC act as intra- and inter-molecular permeation promoters, respectively; however, their underlying mechanisms were different. The former changed the partition equilibrium, while the latter changed the permeation pathway. PoxnoPC inhibited permeation under our experimental conditions via an intra-molecular configuration change. Thus, both intra- and inter-molecular processes were found to control the role of oxidized lipids as inhibitors and promoters towards H2O2 permeation with different mechanisms depending on structure and composition. Here, we identified two independent H2O2 permeation routes: (i) permeation through lipid membrane with increased partition coefficient by intra-molecular configurational change and (ii) diffusion through pores (water channels) formed by inter-molecular configurational change of oxidized lipids. We provide new insight into how biological cells control permeation of molecules through intra- and inter-molecular configurational changes in the lipid membrane. Thus, by employing a rational design for both oxidized lipids and other components, the permeation behaviour of H2O2 and other ions and molecules through a lipid membrane could be controlled.
Collapse
Affiliation(s)
- Yuya Ouchi
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata, 990-8560, Japan
| | - Kei Unoura
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata, 990-8560, Japan
| | - Hideki Nabika
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata, 990-8560, Japan.
| |
Collapse
|
32
|
Effects of Cholesterol on Water Permittivity of Biomimetic Ion Pair Amphiphile Bilayers: Interplay between Membrane Bending and Molecular Packing. Int J Mol Sci 2019; 20:ijms20133252. [PMID: 31269714 PMCID: PMC6651711 DOI: 10.3390/ijms20133252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 06/28/2019] [Accepted: 06/28/2019] [Indexed: 02/04/2023] Open
Abstract
Ion pair amphiphile (IPA), a molecular complex composed of a pair of cationic and anionic amphiphiles, is an inexpensive phospholipid substitute to fabricate vesicles with various pharmaceutical applications. Modulating the physicochemical and permeation properties of IPA vesicles are important for carrier designs. Here, we applied molecular dynamics simulations to examine the cholesterol effects on the structures, mechanics, and water permittivity of hexadecyltrimethylammonium-dodecylsulfate (HTMA-DS) and dodecyltrimethylammonium- hexadecylsulfate (DTMA-HS) IPA bilayers. Structural and mechanical analyses indicate that both IPA systems are in gel phase at 298 K. Adding cholesterol induces alkyl chain ordering around the rigid sterol ring and increases the cavity density within the hydrophilic region of both IPA bilayers. Furthermore, the enhanced alkyl chain ordering and the membrane deformation energy induced by cholesterol increase the permeation free energy penalty. In contrast, cholesterol has minor effects on the water local diffusivities within IPA membranes. Overall, the cholesterol reduces the water permittivity of rigid IPA membranes due to the synergistic effects of increased alkyl chain ordering and enhanced membrane mechanical modulus. The results provide molecular insights into the effects of molecular packing and mechanical deformations on the water permittivity of biomimetic IPA membranes, which is critical for designing IPA vesicular carriers.
Collapse
|
33
|
Kirsch SA, Böckmann RA. Coupling of Membrane Nanodomain Formation and Enhanced Electroporation near Phase Transition. Biophys J 2019; 116:2131-2148. [PMID: 31103234 PMCID: PMC6554532 DOI: 10.1016/j.bpj.2019.04.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 04/17/2019] [Accepted: 04/18/2019] [Indexed: 12/29/2022] Open
Abstract
Biological cells are enveloped by a heterogeneous lipid bilayer that prevents the uncontrolled exchange of substances between the cell interior and its environment. In particular, membranes act as a continuous barrier for salt and macromolecules to ensure proper physiological functions within the cell. However, it has been shown that membrane permeability strongly depends on temperature and, for phospholipid bilayers, displays a maximum at the transition between the gel and fluid phase. Here, extensive molecular dynamics simulations of dipalmitoylphosphatidylcholine bilayers were employed to characterize the membrane structure and dynamics close to phase transition, as well as its stability with respect to an external electric field. Atomistic simulations revealed the dynamic appearance and disappearance of spatially related nanometer-sized thick ordered and thin interdigitating domains in a fluid-like bilayer close to the phase transition temperature (Tm). These structures likely represent metastable precursors of the ripple phase that vanished at increased temperatures. Similarly, a two-phase bilayer with coexisting gel and fluid domains featured a thickness minimum at the interface because of splaying and interdigitating lipids. For all systems, application of an external electric field revealed a reduced bilayer stability with respect to pore formation for temperatures close to Tm. Pore formation occurred exclusively in thin interdigitating membrane nanodomains. These findings provide a link between the increased membrane permeability and the structural heterogeneity close to phase transition.
Collapse
Affiliation(s)
- Sonja A Kirsch
- Computational Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
| | - Rainer A Böckmann
- Computational Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany.
| |
Collapse
|
34
|
Abstract
This Review illustrates the evaluation of permeability of lipid membranes from molecular dynamics (MD) simulation primarily using water and oxygen as examples. Membrane entrance, translocation, and exit of these simple permeants (one hydrophilic and one hydrophobic) can be simulated by conventional MD, and permeabilities can be evaluated directly by Fick's First Law, transition rates, and a global Bayesian analysis of the inhomogeneous solubility-diffusion model. The assorted results, many of which are applicable to simulations of nonbiological membranes, highlight the limitations of the homogeneous solubility diffusion model; support the utility of inhomogeneous solubility diffusion and compartmental models; underscore the need for comparison with experiment for both simple solvent systems (such as water/hexadecane) and well-characterized membranes; and demonstrate the need for microsecond simulations for even simple permeants like water and oxygen. Undulations, subdiffusion, fractional viscosity dependence, periodic boundary conditions, and recent developments in the field are also discussed. Last, while enhanced sampling methods and increasingly sophisticated treatments of diffusion add substantially to the repertoire of simulation-based approaches, they do not address directly the critical need for force fields with polarizability and multipoles, and constant pH methods.
Collapse
Affiliation(s)
- Richard M Venable
- Laboratory of Computational Biology, National Lung, Heart, and Blood Institute , National Institutes of Health , Bethesda , Maryland 20892 , United States
| | - Andreas Krämer
- Laboratory of Computational Biology, National Lung, Heart, and Blood Institute , National Institutes of Health , Bethesda , Maryland 20892 , United States
| | - Richard W Pastor
- Laboratory of Computational Biology, National Lung, Heart, and Blood Institute , National Institutes of Health , Bethesda , Maryland 20892 , United States
| |
Collapse
|
35
|
Sharma VK, Qian S. Effect of an Antimicrobial Peptide on Lateral Segregation of Lipids: A Structure and Dynamics Study by Neutron Scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4152-4160. [PMID: 30720281 DOI: 10.1021/acs.langmuir.8b04158] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Antimicrobial peptides are one of the most promising classes of antibiotic agents for drug-resistant bacteria. Although the mechanisms of their action are not fully understood, many of them are found to interact with the target bacterial membrane, causing different degrees of perturbations. In this work, we directly observed that a short peptide disturbs membranes by inducing lateral segregation of lipids without forming pores or destroying membranes. Aurein 1.2 (aurein) is a 13-amino acid antimicrobial peptide discovered in the frog Litoria genus that exhibits high antibiotic efficacy. Being cationic and amphiphilic, it binds spontaneously to a membrane surface with or without charged lipids. With a small-angle neutron scattering contrast matching technique that is sensitive to lateral heterogeneity in membrane, we found that aurein induces significant lateral segregation in an initially uniform lipid bilayer composed of zwitterionic lipid and anionic lipid. More intriguingly, the lateral segregation was similar to the domain formed below the order-disorder phase-transition temperature. To our knowledge, this is the first direct observation of lateral segregation caused by a peptide. With quasi-elastic neutron scattering, we indeed found that the lipid lateral motion in the fluid phase was reduced even at low aurein concentrations. The reduced lateral mobility makes the membrane prone to additional stresses and defects that change membrane properties and impede membrane-related biological processes. Our results provide insights into how a short peptide kills bacteria at low concentrations without forming pores or destroying membranes. With a better understanding of the interaction, more effective and economically antimicrobial peptides may be designed.
Collapse
Affiliation(s)
- Veerendra K Sharma
- Solid State Physics Division , Bhabha Atomic Research Centre , Mumbai 400085 , India
| | - Shuo Qian
- Neutron Scattering Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
| |
Collapse
|
36
|
Oxygen distribution in the fluid/gel phases of lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:879-886. [PMID: 30716292 DOI: 10.1016/j.bbamem.2019.01.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 01/30/2019] [Accepted: 01/31/2019] [Indexed: 01/25/2023]
Abstract
The interactions between oxygen and lipid membranes play fundamental roles in basic biological processes (e.g., cellular respiration). Obviously, membrane oxidation is expected to be critically dependent on the distribution and concentration of oxygen in the membrane. Here, we combined theoretical and experimental methods to investigate oxygen partition and distribution in lipid membranes of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in a temperature range between 298 and 323 K, specifically focusing on the changes caused by the lipid phase and phase transition. Even though oxygen is known to be more concentrated in the center of fluid phase membranes than on the headgroup regions, the distribution profile of oxygen inside gel-phase bilayers remained to be determined. Molecular dynamics simulations now show that the distribution of oxygen inside DPPC bilayers dramatically changes upon crossing the main transition temperature, with oxygen being nearly depleted halfway from the headgroups to the membrane center below the transition temperature. In a parallel approach, singlet oxygen luminescence emission measurements employing the photosensitizer Pheophorbide-a (Pheo) confirmed the differences in oxygen distribution and concentration profiles between gel- and fluid-phase membranes, revealing changes in the microenvironment of the embedded photosensitizer. Our results also reveal that excited triplet state lifetime, as it can be determined from the singlet oxygen luminescence kinetics, is a useful probe to assess oxygen distribution in lipid membranes with distinct lipid compositions.
Collapse
|