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Munusamy S, Conde R, Bertrand B, Munoz-Garay C. Biophysical approaches for exploring lipopeptide-lipid interactions. Biochimie 2020; 170:173-202. [PMID: 31978418 PMCID: PMC7116911 DOI: 10.1016/j.biochi.2020.01.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 01/19/2020] [Indexed: 02/07/2023]
Abstract
In recent years, lipopeptides (LPs) have attracted a lot of attention in the pharmaceutical industry due to their broad-spectrum of antimicrobial activity against a variety of pathogens and their unique mode of action. This class of compounds has enormous potential for application as an alternative to conventional antibiotics and for pest control. Understanding how LPs work from a structural and biophysical standpoint through investigating their interaction with cell membranes is crucial for the rational design of these biomolecules. Various analytical techniques have been developed for studying intramolecular interactions with high resolution. However, these tools have been barely exploited in lipopeptide-lipid interactions studies. These biophysical approaches would give precise insight on these interactions. Here, we reviewed these state-of-the-art analytical techniques. Knowledge at this level is indispensable for understanding LPs activity and particularly their potential specificity, which is relevant information for safe application. Additionally, the principle of each analytical technique is presented and the information acquired is discussed. The key challenges, such as the selection of the membrane model are also been briefly reviewed.
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Affiliation(s)
- Sathishkumar Munusamy
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210, Cuernavaca, Mexico
| | - Renaud Conde
- Centro de Investigación Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
| | - Brandt Bertrand
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210, Cuernavaca, Mexico
| | - Carlos Munoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210, Cuernavaca, Mexico.
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Chu X, Aydin F, Dutt M. Modeling Interactions between Multicomponent Vesicles and Antimicrobial Peptide-Inspired Nanoparticles. ACS NANO 2016; 10:7351-7361. [PMID: 27434532 DOI: 10.1021/acsnano.5b08133] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We examine the interaction between peptide-inspired nanoparticles, or nanopins, and multicomponent vesicles using the dissipative particle dynamics simulation technique. We study the role of nanopin architecture and cholesterol concentration on the binding of the nanopins to the lipid bilayer, their insertion, and postembedding self-organization. We find the insertion to be triggered by enthalpically unfavorable interactions between the hydrophilic solvent and the lipophilic components of the nanopins. The nanopins are observed to form aggregates in solution, insert into the bilayer, and disassemble into the individual nanopins following the insertion process. We examine factors that influence the orientation of the nanopins in the host vesicle. We report the length of the hydrophilic segment of the nanopins to regulate their orientation within the clusters before the embedding process and in the bilayer, after the postinsertion disassembly of the aggregates. The orientation angle distribution for a given nanopin architecture is found to be driven by energy minimization. In addition, higher concentration of cholesterol is observed to constrain the orientation of the nanopins. We also report thermal fluctuations to induce transverse diffusion of nanopins with specific architectures. The incidence of transverse diffusion is observed to decrease with the concentration of cholesterol. Our results can provide guidelines for designing peptide-inspired nanoparticles or macromolecules that can interface with living cells to serve as sensors for applications in medicine, sustainability, and energy.
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Affiliation(s)
- Xiaolei Chu
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey , Piscataway, New Jersey 08854, United States
| | - Fikret Aydin
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey , Piscataway, New Jersey 08854, United States
| | - Meenakshi Dutt
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey , Piscataway, New Jersey 08854, United States
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Azouzi S, El Kirat K, Morandat S. Hematin loses its membranotropic activity upon oligomerization into malaria pigment. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:2952-9. [PMID: 26296297 DOI: 10.1016/j.bbamem.2015.08.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 08/05/2015] [Accepted: 08/16/2015] [Indexed: 11/24/2022]
Abstract
Malaria is an infectious disease caused by Plasmodium type parasites transmitted by the bites of infected female anopheles mosquitoes. The malaria parasite multiplies in red blood cells where it degrades hemoglobin. This degradation of hemoglobin proteins releases hematin, an iron-containing porphyrin, which provokes membrane disruption and lysis. The malaria parasite blocks hematin-induced lysis by biocrystallization, a process that converts hematin into insoluble and chemically inert crystals. Hematin molecules are especially prone to self-assembly as dimers, oligomers and aggregates depending on environmental conditions (pH, solvent, temperature, concentration, ionic strength). Considering the different forms of hematin-based assemblies, it is still unclear which are the ones able to interact with membranes. We have prepared hematin under different conditions to form hematin-based assemblies and to measure their ability to interact and to disorganize membranes. Our results show that different forms of hematin molecules are able to penetrate lipid membranes. Interestingly, this membrane activity is spontaneously inhibited at acidic pH and it can be restored under neutral pH. By contrast, the oligomers of β-hematin were found to be completely harmless toward lipid membranes. Finally, the AFM visualization of hematin interaction with supported lipid bilayers showed for the first time its preferential interaction with defaults in membranes, at the boundaries between two distinct lipid phases. The superficial adsorption of aggregates on membranes and the absence of effect due to oligomers were also confirmed with AFM.
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Affiliation(s)
- Slim Azouzi
- Laboratoire d'excellence GR-Ex, Inserm S1134, Université Paris-Diderot, Institut National de la Transfusion Sanguine, 6, rue Alexandre Cabanel, 75739 Paris cedex 15, France
| | - Karim El Kirat
- Sorbonne universités, Université de technologie de Compiègne, CNRS, Laboratoire de BioMécanique et BioIngénierie UMR 7338, Centre de recherche Royallieu, CS 60 319, 60 203 Compiègne cedex, France
| | - Sandrine Morandat
- Sorbonne universités, Université de technologie de Compiègne, CNRS, Laboratoire de Génie Enzymatique et Cellulaire FRE 3580, Centre de recherche Royallieu, CS 60 319, 60 203 Compiègne cedex, France.
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Deleu M, Crowet JM, Nasir MN, Lins L. Complementary biophysical tools to investigate lipid specificity in the interaction between bioactive molecules and the plasma membrane: A review. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:3171-3190. [DOI: 10.1016/j.bbamem.2014.08.023] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 08/05/2014] [Accepted: 08/21/2014] [Indexed: 02/08/2023]
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5
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Galatola R, Cruz A, Gómara MJ, Prat J, Alsina MA, Haro I, Pujol M. Surface behavior of peptides from E1 GBV-C protein: Interaction with anionic model membranes and importance in HIV-1 FP inhibition. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:392-407. [PMID: 25450346 DOI: 10.1016/j.bbamem.2014.10.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Revised: 10/20/2014] [Accepted: 10/21/2014] [Indexed: 11/25/2022]
Abstract
The interaction between a peptide sequence from GB virus C E1 protein (E1P8) and its structural analogs (E1P8-12), (E1P8-13), and (E1P8-21) with anionic lipid membranes (POPG vesicles and POPG, DPPG or DPPC/DPPG (2:1) monolayers) and their association with HIV-1 fusion peptide (HIV-1 FP) inhibition at the membrane level were studied using biophysical methods. All peptides showed surface activity but leakage experiments in vesicles as well as insertion kinetics in monolayers and lipid/peptide miscibility indicated a low level of interaction: neither E1P8 nor its analogs induced the release of vesicular content and the exclusion pressure values (πe) were clearly lower than the biological membrane pressure (24-30 mN m(-1)) and the HIV-1 FP (35 mN m(-1)). Miscibility was elucidated in terms of the additivity rule and excess free energy of mixing (GE). E1P8, E1P8-12 and E1P8-21 (but not E1P8-13) induced expansion of the POPG monolayer. The mixing process is not thermodynamically favored as the positive GE values indicate. To determine how E1 peptides interfere in the action of HIV-1 FP at the membrane level, mixed monolayers of HIV-1 FP/E1 peptides (2:1) and POPG were obtained. E1P8 and its derivative E1P8-21 showed the greatest HIV-1 FP inhibition. The LC-LE phase lipid behavior was morphologically examined via fluorescence microscopy (FM) and atomic force microscopy (AFM). Images revealed that the E1 peptides modify HIV-1 FP-lipid interaction. This fact may be attributed to a peptide/peptide interaction as indicated by AFM results. Finally, hemolysis assay demonstrated that E1 peptides inhibit HIV-1 FP activity.
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Affiliation(s)
- R Galatola
- Unit of Synthesis and Biomedical Application of Peptides, Department of Biomedical Chemistry, IQAC-CSIC, Jordi Girona 18, 08034, Barcelona, Spain
| | - A Cruz
- Dept. de Bioquímica y Biología Molecular I, Facultad de Biología, Universidad Complutense, 28040 Madrid, Spain
| | - M J Gómara
- Unit of Synthesis and Biomedical Application of Peptides, Department of Biomedical Chemistry, IQAC-CSIC, Jordi Girona 18, 08034, Barcelona, Spain
| | - J Prat
- Physical Chemistry Department, Faculty of Pharmacy, University of Barcelona, CSIC-Associated Unit: Peptides and Proteins: Physicochemical Studies, IN2UB Av. Joan XXIII s/n, 08028 Barcelona, Spain; Unit of Synthesis and Biomedical Application of Peptides, Department of Biomedical Chemistry, IQAC-CSIC, Jordi Girona 18, 08034, Barcelona, Spain
| | - M A Alsina
- Physical Chemistry Department, Faculty of Pharmacy, University of Barcelona, CSIC-Associated Unit: Peptides and Proteins: Physicochemical Studies, IN2UB Av. Joan XXIII s/n, 08028 Barcelona, Spain
| | - I Haro
- Unit of Synthesis and Biomedical Application of Peptides, Department of Biomedical Chemistry, IQAC-CSIC, Jordi Girona 18, 08034, Barcelona, Spain
| | - M Pujol
- Physical Chemistry Department, Faculty of Pharmacy, University of Barcelona, CSIC-Associated Unit: Peptides and Proteins: Physicochemical Studies, IN2UB Av. Joan XXIII s/n, 08028 Barcelona, Spain.
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Wargenau A, Tufenkji N. Direct detection of the gel-fluid phase transition of a single supported phospholipid bilayer using quartz crystal microbalance with dissipation monitoring. Anal Chem 2014; 86:8017-20. [PMID: 25068734 DOI: 10.1021/ac5019183] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Supported phospholipid bilayers (SPBs) are valuable models for fundamental studies of biological membranes and their interaction with biologically relevant solutes or particles. Herein, we demonstrate the capability of the quartz crystal microbalance with dissipation monitoring (QCM-D) to directly detect the gel-fluid phase transition of a SPB. The approach involves comparison of the frequency response of a bare and a bilayer-coated QCM-D crystal during linear temperature variation. Phase transition results in a change of the resonance frequency that coincides directly with the accompanied change in bilayer thickness detected by ellipsometry. Experiments performed at different heating rates further demonstrate the use of dissipation monitoring to determine the phase transition temperature based on the temperature-induced viscosity changes of the ambient medium in the immediate environment of the bilayer. Unlike other methods, the proposed approach enables precise determination of the phase transition of a SPB without the need for thermal equilibration of the measurement chamber and, thus, has great potential for sensitive detection of structural and/or compositional changes of the bilayer.
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Affiliation(s)
- Andreas Wargenau
- Department of Chemical Engineering, McGill University , Montreal, Quebec H3A 0C5, Canada
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Lamprecht C, Hinterdorfer P, Ebner A. Applications of biosensing atomic force microscopy in monitoring drug and nanoparticle delivery. Expert Opin Drug Deliv 2014; 11:1237-53. [PMID: 24809228 DOI: 10.1517/17425247.2014.917078] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The therapeutic effects of medicinal drugs not only depend on their properties, but also on effective transport to the target receptor. Here we highlight recent developments in this discipline and show applications of atomic force microscopy (AFM) that enable us to track the effects of drugs and the effectiveness of nanoparticle delivery at the single molecule level. AREAS COVERED Physiological AFM imaging enables visualization of topographical changes to cells as a result of drug exposure and allows observation of cellular responses that yield morphological changes. When we upgrade the regular measuring tip to a molecular biosensor, it enables investigation of functional changes at the molecular level via single molecule force spectroscopy. EXPERT OPINION Biosensing AFM techniques have generated powerful tools to monitor drug delivery in (living) cells. While technical developments in actual AFM methods have simplified measurements at relevant physiological conditions, understanding both the biological and technical background is still a crucial factor. However, due to its potential impact, we expect the number of application-based biosensing AFM techniques to further increase in the near future.
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Affiliation(s)
- Constanze Lamprecht
- University of Kiel, Institute of Materials Science Biocompatible Nanomaterials , Kaiserstr.2, 24143 Kiel , Germany
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8
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Morandat S, Azouzi S, Beauvais E, Mastouri A, El Kirat K. Atomic force microscopy of model lipid membranes. Anal Bioanal Chem 2012; 405:1445-61. [DOI: 10.1007/s00216-012-6383-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 08/02/2012] [Accepted: 08/24/2012] [Indexed: 10/27/2022]
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AFM characterization of spin-coated multilayered dry lipid films prepared from aqueous vesicle suspensions. Colloids Surf B Biointerfaces 2011; 82:25-32. [DOI: 10.1016/j.colsurfb.2010.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 07/26/2010] [Accepted: 08/04/2010] [Indexed: 11/20/2022]
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10
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Sarker M, Rose J, McDonald M, Morrow MR, Booth V. Modifications to surfactant protein B structure and lipid interactions under respiratory distress conditions: consequences of tryptophan oxidation. Biochemistry 2010; 50:25-36. [PMID: 21128671 DOI: 10.1021/bi101426s] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
These studies detail the altered structure-function relationships caused by oxidation of surfactant protein B (SP-B), a mode of damage thought to be important in acute respiratory distress syndrome (ARDS), a common and frequently fatal condition. An 18-residue fragment comprising the N-terminal helix of SP-B was investigated in oxidized and unmodified forms by solution and solid-state nuclear magnetic resonance (NMR), circular dichroism (CD), and molecular dynamics (MD) simulation. Taken together, the results indicate that tryptophan oxidation causes substantial disruptions in helical structure and lipid interactions. The structural modifications induced by tryptophan oxidation were severe, with a reduction in helical extent from approximately three helical turns to, at most, one turn, and were observed in a variety of solvent environments, including sodium dodecyl sulfate (SDS) micelles, dodecyl phosphocholine (DPC) micelles, and a 40% hexafluoro-2-propanol (HFIP) aqueous solution. The unmodified peptide takes on an orientation within lipid bilayers that is tilted approximately 30° away from an in-plane position. Tryptophan oxidation causes significant modifications to the peptide-lipid interactions, and the peptide likely shifts to a more in-plane orientation within the lipids. Interestingly, the character of the disruptions to peptide-lipid interactions caused by tryptophan oxidation was highly dependent on the charge of the lipid headgroup.
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Affiliation(s)
- Muzaddid Sarker
- Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, NL, Canada
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11
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Bitler A, Lev N, Fridmann-Sirkis Y, Blank L, Cohen SR, Shai Y. Kinetics of interaction of HIV fusion protein (gp41) with lipid membranes studied by real-time AFM imaging. Ultramicroscopy 2010; 110:694-700. [DOI: 10.1016/j.ultramic.2010.02.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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El Kirat K, Morandat S, Dufrêne YF. Nanoscale analysis of supported lipid bilayers using atomic force microscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:750-65. [DOI: 10.1016/j.bbamem.2009.07.026] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/17/2009] [Accepted: 07/23/2009] [Indexed: 12/11/2022]
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13
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El Kirat K, Morandat S. Cytochrome c interaction with neutral lipid membranes: influence of lipid packing and protein charges. Chem Phys Lipids 2009; 162:17-24. [DOI: 10.1016/j.chemphyslip.2009.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Revised: 08/05/2009] [Accepted: 08/13/2009] [Indexed: 10/20/2022]
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Lins L, El Kirat K, Charloteaux B, Flore C, Stroobant V, Thomas A, Dufrene Y, Brasseur R. Lipid-destabilizing properties of the hydrophobic helices H8 and H9 from colicin E1. Mol Membr Biol 2009; 24:419-30. [PMID: 17710646 DOI: 10.1080/09687860701228254] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Colicins are toxic proteins produced by Escherichia coli that must cross the membrane to exert their activity. The lipid insertion of their pf domain is linked to a conformational change which enables the penetration of a hydrophobic hairpin. They provide useful models to more generally study insertion of proteins, channel formation and protein translocation in and across membranes. In this paper, we study the lipid-destabilizing properties of helices H8 and H9 forming the hydrophobic hairpin of colicin E1. Modelling analysis suggests that those fragments behave like tilted peptides. The latter are characterized by an asymmetric distribution of their hydrophobic residues when helical. They are able to interact with a hydrophobic/hydrophilic interface (such as a lipid membrane) and to destabilize the organized system into which they insert. Fluorescence techniques using labelled liposomes clearly show that H9, and H8 to a lesser extent, destabilize lipid particles, by inducing fusion and leakage. AFM assays clearly indicate that H8 and especially H9 induce membrane fragilization. Holes in the membrane are even observed in the presence of H9. This behaviour is close to what is seen with viral fusion peptides. Those results suggest that the peptides could be involved in the toroidal pore formation of colicin E1, notably by disturbing the lipids and facilitating the insertion of the other, more hydrophilic, helices that will form the pore. Since tilted, lipid-destabilizing fragments are also common to membrane proteins and to signal sequences, we suggest that tilted peptides should have an ubiquitous role in the mechanism of insertion of proteins into membranes.
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Affiliation(s)
- L Lins
- Centre de Biophysique Moléculaire Numérique, Faculté des Sciences, Agronomiques de Gembloux, Gembloux, Belgium.
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Nanoscale membrane activity of surfactins: Influence of geometry, charge and hydrophobicity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:2058-68. [DOI: 10.1016/j.bbamem.2008.03.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 03/21/2008] [Accepted: 03/31/2008] [Indexed: 11/18/2022]
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Relationships between the orientation and the structural properties of peptides and their membrane interactions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:1537-44. [DOI: 10.1016/j.bbamem.2008.04.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2007] [Revised: 04/14/2008] [Accepted: 04/21/2008] [Indexed: 11/17/2022]
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Shahin V, Barrera NP. Providing Unique Insight into Cell Biology via Atomic Force Microscopy. INTERNATIONAL REVIEW OF CYTOLOGY 2008; 265:227-52. [DOI: 10.1016/s0074-7696(07)65006-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Blistering of supported lipid membranes induced by Phospholipase D, as observed by real-time atomic force microscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:276-82. [DOI: 10.1016/j.bbamem.2007.09.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Revised: 09/11/2007] [Accepted: 09/28/2007] [Indexed: 11/21/2022]
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Brasseur R, Deleu M, Mingeot-Leclercq MP, Francius G, Dufrêne YF. Probing peptide–membrane interactions using AFM. SURF INTERFACE ANAL 2008. [DOI: 10.1002/sia.2682] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Giocondi MC, Besson F, Dosset P, Milhiet PE, Le Grimellec C. Remodeling of ordered membrane domains by GPI-anchored intestinal alkaline phosphatase. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:9358-64. [PMID: 17661499 DOI: 10.1021/la700892z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Glycosylphosphatidyl-inositol (GPI)-anchored proteins preferentially localize in the most ordered regions of the cell plasma membrane. Acyl and alkyl chain composition of GPI anchors influence the association with the ordered domains. This suggests that, conversely, changes in the fluid and in the ordered domains lipid composition affect the interaction of GPI-anchored proteins with membrane microdomains. Validity of this hypothesis was examined by investigating the spontaneous insertion of the GPI-anchored intestinal alkaline phophatase (BIAP) into the solid (gel) phase domains of preformed supported membranes made of dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DOPC/DPPC), DOPC/sphingomyelin (DOPC/SM), and palmitoyloleoylphosphatidylcholine/SM (POPC/SM). Atomic force microscopy (AFM) showed that BIAP inserted in the gel phases of the three mixtures. However, changes in the lipid composition of membranes had a marked effect on the protein containing bilayer topography. Moreover, BIAP insertion was associated with a net transfer of phospholipids from the fluid to the gel (DOPC/DPPC) or from the gel to the fluid (POPC/SM) phases. For DOPC/SM bilayers, transfer of lipids was dependent on the homogeneity of the gel SM phase. The data strongly suggest that BIAP interacts with the most ordered lipid species present in the gel phases of phase-separated membranes. They also suggest that GPI-anchored proteins might contribute to the selection of their own microdomain environment.
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Affiliation(s)
- Marie-Cécile Giocondi
- Institut National de la Santé et de la Recherche Médicale, Unité 554, Montpellier, France
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Fa N, Lins L, Courtoy PJ, Dufrêne Y, Van Der Smissen P, Brasseur R, Tyteca D, Mingeot-Leclercq MP. Decrease of elastic moduli of DOPC bilayers induced by a macrolide antibiotic, azithromycin. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1830-8. [PMID: 17537401 DOI: 10.1016/j.bbamem.2007.04.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 04/06/2007] [Accepted: 04/10/2007] [Indexed: 10/23/2022]
Abstract
The elastic properties of membrane bilayers are key parameters that control its deformation and can be affected by pharmacological agents. Our previous atomic force microscopy studies revealed that the macrolide antibiotic, azithromycin, leads to erosion of DPPC domains in a fluid DOPC matrix [A. Berquand, M. P. Mingeot-Leclercq, Y. F. Dufrene, Real-time imaging of drug-membrane interactions by atomic force microscopy, Biochim. Biophys. Acta 1664 (2004) 198-205.]. Since this observation could be due to an effect on DOPC cohesion, we investigated the effect of azithromycin on elastic properties of DOPC giant unilamellar vesicles (GUVs). Microcinematographic and morphometric analyses revealed that azithromycin addition enhanced lipid membranes fluctuations, leading to eventual disruption of the largest GUVs. These effects were related to change of elastic moduli of DOPC, quantified by the micropipette aspiration technique. Azithromycin decreased both the bending modulus (k(c), from 23.1+/-3.5 to 10.6+/-4.5 k(B)T) and the apparent area compressibility modulus (K(app), from 176+/-35 to 113+/-25 mN/m). These data suggested that insertion of azithromycin into the DOPC bilayer reduced the requirement level of both the energy for thermal fluctuations and the stress to stretch the bilayer. Computer modeling of azithromycin interaction with DOPC bilayer, based on minimal energy, independently predicted that azithromycin (i) inserts at the interface of phospholipid bilayers, (ii) decreases the energy of interaction between DOPC molecules, and (iii) increases the mean surface occupied by each phospholipid molecule. We conclude that azithromycin inserts into the DOPC lipid bilayer, so as to decrease its cohesion and to facilitate the merging of DPPC into the DOPC fluid matrix, as observed by atomic force microscopy. These investigations, based on three complementary approaches, provide the first biophysical evidence for the ability of an amphiphilic antibiotic to alter lipid elastic moduli. This may be an important determinant for drug: lipid interactions and cellular pharmacology.
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Affiliation(s)
- N Fa
- Université Catholique de Louvain, Unité de Pharmacologie Cellulaire et Moléculaire, Avenue E. Mounier 73, Bt 7370, B-1200 Brussels, Belgium
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El Kirat K, Morandat S. Cholesterol modulation of membrane resistance to Triton X-100 explored by atomic force microscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:2300-9. [PMID: 17560898 DOI: 10.1016/j.bbamem.2007.05.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 04/23/2007] [Accepted: 05/03/2007] [Indexed: 02/05/2023]
Abstract
Biomembranes are not homogeneous, they present a lateral segregation of lipids and proteins which leads to the formation of detergent-resistant domains, also called "rafts". These rafts are particularly enriched in sphingolipids and cholesterol. Despite the huge body of literature on raft insolubility in non-ionic detergents, the mechanisms governing their resistance at the nanometer scale still remain poorly documented. Herein, we report a real-time atomic force microscopy (AFM) study of model lipid bilayers exposed to Triton X-100 (TX-100) at different concentrations. Different kinds of supported bilayers were prepared with dioleoylphosphatidylcholine (DOPC), sphingomyelin (SM) and cholesterol (Chol). The DOPC/SM 1:1 (mol/mol) membrane served as the non-resistant control, and DOPC/SM/Chol 2:1:1 (mol/mol/mol) corresponded to the raft-mimicking composition. For all the lipid compositions tested, AFM imaging revealed that TX-100 immediately solubilized the DOPC fluid phase leaving resistant patches of membrane. For the DOPC/SM bilayers, the remaining SM-enriched patches were slowly perforated leaving crumbled features reminiscent of the initial domains. For the raft model mixture, no holes appeared in the remaining SM/Chol patches and some erosion occurred. This work provides new, nanoscale information on the biomembranes' resistance to the TX-100-mediated solubilization, and especially about the influence of Chol.
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Affiliation(s)
- Karim El Kirat
- Laboratoire de Biomécanique et Génie Biomédical, UMR-CNRS 6600, Université de Technologie de Compiègne, BP 20529, 60205 Compiègne Cedex, France
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Silva LP, Leite JRSA, Brand GD, Regis WB, Tedesco AC, Azevedo RB, Freitas SM, Bloch C. Dermaseptins from Phyllomedusa oreades and Phyllomedusa distincta: liposomes fusion and/or lysis investigated by fluorescence and atomic force microscopy. Comp Biochem Physiol A Mol Integr Physiol 2007; 151:329-335. [PMID: 17409003 DOI: 10.1016/j.cbpa.2007.02.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 01/22/2007] [Accepted: 02/26/2007] [Indexed: 11/17/2022]
Abstract
Three dermaseptins, DS 01, DD K, and DD L, were compared with respect to their structural features and interactions with liposomes. Circular dichroic spectra at alcohols of different chain lengths revealed that DS 01 has the higher helicogenic potential in hydrophobic media. Binding of DS 01, DD K, and DD L to liposomes induced significant blue shifts of the emission spectra of the single tryptophan located at position 3 of all sequences indicating association of the peptides with bilayers. Kinetics evaluation of atomic force microscopy images evidenced the strong fusogenic activity of DS 01 whereas DD K and DD L showed increased lytic activities.
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Affiliation(s)
- Luciano P Silva
- Laboratório de Morfologia e Morfogênese, Departamento de Genética e Morfologia, Instituto de Biologia, Universidade de Brasília, Brasília, DF, 70910-900, Brazil; Laboratório de Espectrometria de Massa, Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)-Recursos Genéticos e Biotecnologia, Estação Parque Biológico, Final W5, Asa Norte, Brasília, DF, 70770-900, Brazil.
| | - José Roberto S A Leite
- Laboratório de Espectrometria de Massa, Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)-Recursos Genéticos e Biotecnologia, Estação Parque Biológico, Final W5, Asa Norte, Brasília, DF, 70770-900, Brazil; Campus Ministro Reis Velloso, Universidade Federal do Piauí-UFPI, Parnaíba, Piauí, 64202-020, PI, Brazil
| | - Guilherme D Brand
- Laboratório de Espectrometria de Massa, Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)-Recursos Genéticos e Biotecnologia, Estação Parque Biológico, Final W5, Asa Norte, Brasília, DF, 70770-900, Brazil
| | - Willian B Regis
- Grupo de Biofísica Molecular-Centro de Biologia Molecular Estrutural, Laboratório Nacional de Luz Síncrotron (LNLS), Campinas, SP, Brazil
| | - Antonio C Tedesco
- FFCLRP-USP, Universidade de São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
| | - Ricardo B Azevedo
- Laboratório de Morfologia e Morfogênese, Departamento de Genética e Morfologia, Instituto de Biologia, Universidade de Brasília, Brasília, DF, 70910-900, Brazil
| | - Sonia M Freitas
- Laboratório de Biofísica, Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasília, 70910-900 Brazil
| | - Carlos Bloch
- Laboratório de Espectrometria de Massa, Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)-Recursos Genéticos e Biotecnologia, Estação Parque Biológico, Final W5, Asa Norte, Brasília, DF, 70770-900, Brazil.
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Andre G, Brasseur R, Dufrêne YF. Probing the interaction forces between hydrophobic peptides and supported lipid bilayers using AFM. J Mol Recognit 2007; 20:538-45. [PMID: 17891753 DOI: 10.1002/jmr.837] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Despite the vast body of literature that has accumulated on tilted peptides in the past decade, direct information on the forces that drive their interaction with lipid membranes is lacking. Here, we attempted to use atomic force microscopy (AFM) to explore the interaction forces between the Simian immunodeficiency virus peptide and phase-separated supported bilayers composed of various lipids, i.e. dipalmitoylphosphatidylcholine, dioleoylphosphatidylcholine, dioleoylphosphatidic acid and dipalmitoylphosphatidylethanolamine. Histidine-tagged peptides were attached onto AFM tips terminated with nitrilotriacetate and tri(ethylene glycol) groups, an approach expected to ensure optimal exposure of the C-terminal hydrophobic domain. Force-distance curves recorded between peptide-tips and the different bilayer domains always showed a long-range repulsion upon approach and a lack of adhesion upon retraction, in marked contrast with the hydrophobic nature of the peptide. To explain this unexpected behaviour, we suggest a mechanism in which lipids are pulled out from the bilayer due to strong interactions with the peptide-tip, in agreement with the very low force needed to extract lipids from supported bilayers.
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Affiliation(s)
- Guillaume Andre
- Unité de Chimie des Interfaces, Université catholique de Louvain, Croix du Sud 2/18, 1348 Louvain-la-Neuve, Belgium
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26
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Choucair A, Chakrapani M, Chakravarthy B, Katsaras J, Johnston LJ. Preferential accumulation of Aβ(1−42) on gel phase domains of lipid bilayers: An AFM and fluorescence study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:146-54. [PMID: 17052685 DOI: 10.1016/j.bbamem.2006.09.005] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 09/07/2006] [Accepted: 09/08/2006] [Indexed: 01/09/2023]
Abstract
Peptide-membrane interactions have been implicated in both the toxicity and aggregation of beta-amyloid (Abeta) peptides. Recent studies have provided evidence for the involvement of liquid-ordered membrane domains known as lipid rafts in the formation and aggregation of Abeta. As a model, we have examined the interaction of Abeta(1-42) with phase separated DOPC/DPPC lipid bilayers using a combination of atomic force microscopy (AFM) and total internal reflection fluorescence microscopy (TIRF). AFM images show that addition of Abeta to preformed supported bilayers leads to accumulation of small peptide aggregates exclusively on the gel phase DPPC domains. Initial aggregates are observed approximately 90 min after peptide addition and increase in diameter to 45-150 nm within 24 h. TIRF studies with a mixture of Abeta and Abeta-Fl demonstrate that accumulation of the peptide on the gel phase domains occurs as early as 15 min after Abeta addition and is maintained for over 24 h. By contrast, Abeta is randomly distributed throughout both fluid and gel phases when the peptide is reconstituted into DOPC/DPPC vesicles prior to formation of a supported bilayer. The preferential accumulation of Abeta on DPPC domains suggests that rigid domains may act as platforms to concentrate peptide and enhance its aggregation and may be relevant to the postulated involvement of lipid rafts in modulating Abeta activity in vivo.
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Affiliation(s)
- A Choucair
- Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6
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Morandat S, El Kirat K. Solubilization of supported lipid membranes by octyl glucoside observed by time-lapse atomic force microscopy. Colloids Surf B Biointerfaces 2006; 55:179-84. [PMID: 17207975 DOI: 10.1016/j.colsurfb.2006.11.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Revised: 11/28/2006] [Accepted: 11/30/2006] [Indexed: 12/25/2022]
Abstract
Detergents are very useful for the purification of membrane proteins. A good detergent for protein extraction has to prevent denaturation by unfolding, and to avoid aggregation. Therefore, gaining access to the mechanism of biomembranes' solubilization by detergents is crucial in biochemical research. Among the wide range of detergents used to purify membrane proteins, n-octyl beta-D-glucopyranoside (OG) is one of the most important as it can be easily removed from final protein extracts. Here, we used real-time atomic force microscopy (AFM) imaging to visualize the behavior of a model supported lipid bilayer in the presence of OG. Two kinds of supported model membranes were prepared by fusion of unilamellar vesicles: with an equimolar mixing of dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DOPC/DPPC) or with DPPC alone. Time-lapse AFM experiments evidenced that below its critical micelle concentration (CMC), OG was not able to solubilize the bilayer but the gel DPPC domains were instantly dissolved into the DOPC matrix. This result was interpreted as a disorganization of the DPPC molecular packing induced by OG. When membranes were incubated with OG at concentrations higher than CMC, the detergent immediately provoked the complete and immediate desorption of the whole bilayer for both compositions: DPPC and DOPC/DPPC. After a while, some patches appeared onto the bare mica surface. This redeposition activity, together with fusion events, progressively led to the recovery of a continuous bilayer. These results provide a new insight on the unique properties of OG employed in membrane reconstitution protocols.
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Affiliation(s)
- Sandrine Morandat
- Université de Technologie de Compiègne, Laboratoire de Génie Enzymatique et Cellulaire, UMR-CNRS 6022, BP 20529, 60205 Compiègne Cedex, France
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28
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Morandat S, El Kirat K. Membrane resistance to Triton X-100 explored by real-time atomic force microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:5786-91. [PMID: 16768509 DOI: 10.1021/la0604228] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Lateral segregation of lipids and proteins in biological membranes leads to the formation of detergent-resistant domains, also called "rafts". Understanding the mechanisms governing the biomembrane's resistance to solubilization by detergents is crucial in biochemical research. Here, we used real-time atomic force microscopy (AFM) imaging to visualize the behavior of a model supported lipid bilayer in the presence of different Triton X-100 (TX-100) concentrations. Mixed dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DOPC/DPPC) supported bilayers were prepared by vesicle fusion. Real-time AFM imaging revealed that, at concentrations below the critical micelle concentration (CMC), TX-100 did not solubilize the bilayer, but the DPPC domains were eroded in a time-dependent manner. This effect was attributed to the DPPC molecular packing disorganization by the detergent starting from the DOPC/DPPC interface. Just above the CMC, the detergent led to a complete solubilization of the DOPC matrix, leaving the DPPC domains unaltered. At higher TX-100 concentrations, the DOPC was also immediately removed just after detergent addition, and the DPPC domains remaining on the mica surface appeared to be more swollen and were gradually solubilized. This progressive solubilization of the DPPC remaining phase did not start at the edge of the domains but from holes appearing and expanding at the center of DPPC patches. The swelling of the DPPC domains was directly correlated with TX-100 concentration above the CMC and with detergent intercalation between DPPC molecules. We are convinced that this approach will provide a key system to elucidate the physical mechanisms of membrane solubilization by nonionic detergents.
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Affiliation(s)
- Sandrine Morandat
- Laboratoire de Génie Enzymatique et Cellulaire, Université de Technologie de Compiègne, UMR-CNRS 6022, BP 20529, 60205 Compiègne Cedex, France
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29
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Lorin A, Thomas A, Stroobant V, Brasseur R, Lins L. Lipid-destabilising properties of a peptide with structural plasticity. Chem Phys Lipids 2006; 141:185-96. [PMID: 16672156 DOI: 10.1016/j.chemphyslip.2006.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2005] [Accepted: 02/20/2006] [Indexed: 11/24/2022]
Abstract
The Chameleon peptide (Cham) is a peptide designed from two regions of the GB1 protein, one folded as an alpha-helix and the other as a beta structure. Depending on the environment, the Cham peptide adopts an alpha or a beta conformation when inserted in different locations of GB1. This environment dependence is also observed for tilted peptides. These short protein fragments, able to destabilise organised system, are mainly folded in beta structure in water and in alpha helix in a hydrophobic environment, like the lipid bilayer. In this paper, we tested whether the Cham peptide can be qualified as a tilted peptide. For this, we have compared the properties of Cham peptide (hydrophobicity, destabilising properties, conformation) to those of tilted peptides. The results suggest that Cham is a tilted peptide. Our study, together the presence of tilted fragments in transconformational proteins, suggests a relationship between tilted peptides and structural lability.
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Affiliation(s)
- A Lorin
- Centre de Biophysique Moléculaire Numérique, Faculté Universitaire des Sciences Agronomiques, Gembloux, Belgium
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Charloteaux B, Lorin A, Crowet JM, Stroobant V, Lins L, Thomas A, Brasseur R. The N-terminal 12 Residue Long Peptide of HIV gp41 is the Minimal Peptide Sufficient to Induce Significant T-cell-like Membrane Destabilization in Vitro. J Mol Biol 2006; 359:597-609. [PMID: 16677669 DOI: 10.1016/j.jmb.2006.04.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2006] [Accepted: 04/03/2006] [Indexed: 11/26/2022]
Abstract
Here, we predicted the minimal N-terminal fragment of gp41 required to induce significant membrane destabilization using IMPALA. This algorithm is dedicated to predict peptide interaction with a membrane. We based our prediction of the minimal fusion peptide on the tilted peptide theory. This theory proposes that some protein fragments having a peculiar distribution of hydrophobicity adopt a tilted orientation at a hydrophobic/hydrophilic interface. As a result of this orientation, tilted peptides should disrupt the interface. We analysed in silico the membrane-interacting properties of gp41 N-terminal peptides of different length derived from the isolate BRU and from an alignment of 710 HIV strains available on the Los Alamos National Laboratory. Molecular modelling results indicated that the 12 residue long peptide should be the minimal fusion peptide. We then assayed lipid-mixing and leakage of T-cell-like liposomes with N-terminal peptides of different length as first challenge of our predictions. Experimental results confirmed that the 12 residue long peptide is necessary and sufficient to induce membrane destabilization to the same extent as the 23 residue long fusion peptide. In silico analysis of some fusion-incompetent mutants presented in the literature further revealed that they cannot insert into a modelled membrane correctly tilted. According to this work, the tilted peptide model appears to explain at least partly the membrane destabilization properties of HIV fusion peptide.
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Affiliation(s)
- B Charloteaux
- Centre de Biophysique Moléculaire Numérique, Faculté Universitaire des Sciences Agronomiques, Passage des déportés, B-5030 Gembloux, Belgium.
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Shaw JE, Alattia JR, Verity JE, Privé GG, Yip CM. Mechanisms of antimicrobial peptide action: Studies of indolicidin assembly at model membrane interfaces by in situ atomic force microscopy. J Struct Biol 2006; 154:42-58. [PMID: 16459101 DOI: 10.1016/j.jsb.2005.11.016] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 10/13/2005] [Accepted: 11/09/2005] [Indexed: 11/21/2022]
Abstract
We report here on an in situ atomic force microscopy study of the interaction of indolicidin, a tryptophan-rich antimicrobial peptide, with phase-segregated zwitterionic DOPC/DSPC supported planar bilayers. By varying the peptide concentration and bilayer composition through the inclusion of anionic lipids (DOPG or DSPG), we found that indolicidin interacts with these model membranes in one of two concentration-dependent manners. At low peptide concentrations, indolicidin forms an amorphous layer on the fluid domains when these domains contain anionic lipids. At high peptide concentrations, indolicidin appears to initiate a lowering of the gel-phase domains independent of the presence of an anionic lipid. Similar studies performed using membrane-raft mimetic bilayers comprising 30mol% cholesterol/1:1 DOPC/egg sphingomyelin revealed that indolicidin does not form a carpet-like layer on the zwitterionic DOPC domains at low peptide concentrations and does not induce membrane lowering of the liquid-ordered sphingomyelin/cholesterol-rich domains at high peptide concentration. Simultaneous AFM-confocal microscopy imaging did however reveal that indolicidin preferentially inserts into the fluid-phase DOPC domains. These data suggest that the indolicidin-membrane association is influenced greatly by specific electrostatic interactions, lipid fluidity, and peptide concentration. These insights provide a glimpse into the mechanism of the membrane selectivity of antibacterial peptides and suggest a powerful correlated approach for characterizing peptide-membrane interactions.
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Affiliation(s)
- James E Shaw
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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