1
|
Alvarez AB, Caruso B, Petersen SB, Rodríguez PEA, Fidelio GD. Melittin-solid phospholipid mixed films trigger amyloid-like nano-fibril arrangements at air-water interface. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:184048. [PMID: 36115495 DOI: 10.1016/j.bbamem.2022.184048] [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: 03/14/2022] [Revised: 08/22/2022] [Accepted: 09/06/2022] [Indexed: 06/15/2023]
Abstract
We used the Langmuir monolayers technique to study the surface properties of melittin toxin mixed with either liquid-condensed DSPC or liquid-expanded POPC phospholipids. Pure melittin peptide forms stable insoluble monolayers at the air-water interface without interacting with Thioflavin T (Th-T), a sensitive probe to detect protein amyloid formation. When melittin peptide is mixed with DSPC lipid at 50 % of peptide area proportion at the surface, we observed the formation of fibril-like structures detected by Brewster angle microscopy (BAM), but they were not observable with POPC. The nano-structures in the melittin-DSPC mixtures became Th-T positive labeling when the arrangement was observed with fluorescence microscopy. In this condition, Th-T undergoes an unexpected shift in the typical emission wavelength of this amyloid marker when a 2D fluorescence analysis is conducted. Even when reflectivity analysis of BAM imaging evidenced that these structures would correspond to the DSPC lipid component of the mixture, the interpretation of ATR-FTIR and Th-T data suggested that both components were involved in a new lipid-peptide rearrangement. These nano-fibril arrangements were also evidenced by scanning electron and atomic force microscopy when the films were transferred to a mica support. The fibril formation was not detected when melittin was mixed with the liquid-expanded POPC lipid. We postulated that DSPC lipids can dynamically trigger the process of amyloid-like nano-arrangement formation at the interface. This process is favored by the relative peptide content, the quality of the interfacial environment, and the physical state of the lipid at the surface.
Collapse
Affiliation(s)
- Alain Bolaño Alvarez
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina; Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Universidad Nacional de Córdoba, Argentina
| | - Benjamín Caruso
- Cátedra de Química Biológica, Departamento de Química, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Argentina; Instituto de Investigaciones Biológicas y Tecnológicas (IIBYT), CONICET, Universidad Nacional de Córdoba. Córdoba, Argentina
| | | | | | - Gerardo D Fidelio
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina; Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Universidad Nacional de Córdoba, Argentina.
| |
Collapse
|
2
|
Syryamina VN, Afanasyeva EF, Dzuba SA, Formaggio F, De Zotti M. Peptide-membrane binding is not enough to explain bioactivity: A case study. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183978. [PMID: 35659865 DOI: 10.1016/j.bbamem.2022.183978] [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: 03/16/2022] [Revised: 05/11/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
Membrane-active peptides are a promising class of antimicrobial and anticancer therapeutics. For this reason, their molecular mechanisms of action are currently actively investigated. By exploiting Electron Paramagnetic Resonance, we study the membrane interaction of two spin-labeled analogs of the antimicrobial and cytotoxic peptide trichogin GA IV (Tri), with opposite bioactivity: Tri(Api8), able to selectively kill cancer cells, and Tri(Leu4), which is completely nontoxic. In our attempt to determine the molecular basis of their different biological activity, we investigate peptide impact on the lateral organization of lipid membranes, peptide localization and oligomerization, in the zwitter-ionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) model membrane We show that, despite their divergent bioactivity, both peptide analogs (i) are membrane-bound, (ii) display a weak tendency to oligomerization, and (iii) do not induce significant lipid rearrangement. Conversely, literature data show that the parent peptide trichogin, which is cytotoxic without any selectivity, is strongly prone to dimerization and affects the reorganization of POPC membranes. Its dimers are involved in the rotation around the peptide helix, as observed at cryogenic temperatures in the millisecond timescale. Since this latter behavior is not observed for the inactive Tri(Leu4), we propose that for short-length peptides as trichogin oligomerization and molecular motions are crucial for bioactivity, and membrane binding alone is not enough to predict or explain it. We envisage that small changes in the peptide sequence that affect only their ability to oligomerize, or their molecular motions inside the membrane, can tune the peptide activity on membranes of different compositions.
Collapse
Affiliation(s)
- Victoria N Syryamina
- Voevodsky Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation.
| | - Ekaterina F Afanasyeva
- Voevodsky Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation
| | - Sergei A Dzuba
- Voevodsky Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation; Department of Physics, Novosibirsk State University,630090 Novosibirsk, Russian Federation
| | - Fernando Formaggio
- ICB-CNR, Padova Unit, Department of Chemistry, University of Padova, 35131 Padova, Italy
| | - Marta De Zotti
- ICB-CNR, Padova Unit, Department of Chemistry, University of Padova, 35131 Padova, Italy.
| |
Collapse
|
3
|
Picoli T, Peter C, Lopes M, Barcelos L, Varela Júnior A, Corcini C, Hübner S, Vargas G, Lima M, Fischer G. Melittin-induced metabolic changes on the Madin-Darby Bovine Kidney cell line. ARQ BRAS MED VET ZOO 2021. [DOI: 10.1590/1678-4162-12150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ABSTRACT In this study, the toxic effects of melittin on Madin-Darby Bovine Kidney cells (MDBK) were analyzed with respect to mitochondrial functionality by reduction of MTT and flow cytometry, apoptosis potential, necrosis, oxygen reactive species (ROS) production, lipid peroxidation, and DNA fragmentation using flow cytometry and cell membrane destabilization by confocal microscopy. The toxicity presented dose-dependent characteristics and mitochondrial activity was inhibited by up to 78.24 ±3.59% (P<0.01, n = 6) in MDBK cells exposed to melittin (10μg/mL). Flow cytometry analysis revealed that melittin at 2μg/mL had the highest necrosis rate (P<0.05) for the cells. The lipoperoxidation of the membranes was also higher at 2μg/mL of melittin (P<0.05), which was further confirmed by the microphotographs obtained by confocal microscopy. The highest ROS production occurred when the cells were exposed to 2.5μg/mL melittin (P<0.05), and this concentration also increased DNA fragmentation (P<0.05). There was a significative and positive correlation between the lipoperoxidation of membranes with ROS (R=0.4158), mitochondrial functionality (R=0.4149), and apoptosis (R=0.4978). Thus, the oxidative stress generated by melittin culminates in the elevation of intracellular ROS that initiates a cascade of toxic events in MDBK cells.
Collapse
Affiliation(s)
- T. Picoli
- Universidade Federal de Pelotas, Brazil
| | | | | | | | | | | | | | | | - M. Lima
- Universidade Federal de Pelotas, Brazil
| | | |
Collapse
|
4
|
Syryamina VN, Sannikova NE, De Zotti M, Gobbo M, Formaggio F, Dzuba SA. Tylopeptin B peptide antibiotic in lipid membranes at low concentrations: Self-assembling, mutual repulsion and localization. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183585. [PMID: 33640429 DOI: 10.1016/j.bbamem.2021.183585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/27/2021] [Accepted: 02/08/2021] [Indexed: 02/08/2023]
Abstract
The medium-length peptide Tylopeptin B possesses activity against Gram-positive bacteria. It binds to bacterial membranes altering their mechanical properties and increasing their permeability. This action is commonly related with peptide self-assembling, resulting in the formation of membrane channels. Here, pulsed double electron-electron resonance (DEER) data for spin-labeled Tylopeptin B in palmitoyl-oleoyl-glycero-phosphocholine (POPC) model membrane reveal that peptide self-assembling starts at concentration as low as 0.1 mol%; above 0.2 mol% it attains a saturation-like dependence with a mean number of peptides in the cluster <n> = 3.3. Using the electron spin echo envelope modulation (ESEEM) technique, Tylopeptin B molecules are found to possess a planar orientation in the membrane. In the peptide concentration range between 0.1 and 0.2 mol%, DEER data show that the peptide clusters have tendency of mutual repulsion, with a circle of inaccessibility of radius around 20 nm. It may be proposed that within this radius the peptides destabilize the membrane, providing so the peptide antimicrobial activity. Exploiting spin-labeled stearic acids as a model for free fatty acids (FFA), we found that at concentrations of 0.1-0.2 mol% the peptide promotes formation of lipid-mediated FFA clusters; further increase in peptide concentration results in dissipation of these clusters.
Collapse
Affiliation(s)
- Victoria N Syryamina
- Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation.
| | | | - Marta De Zotti
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy; Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
| | - Marina Gobbo
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy; Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
| | - Fernando Formaggio
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy; Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
| | - Sergei A Dzuba
- Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation.
| |
Collapse
|
5
|
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] [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. A brief overview of topics to understand the generalities of lipopeptide (LP) science. Main analytical techniques used to reveal the interaction and the distorting effect of LP on artificial membranes. Guidelines for selecting of the most adequate membrane models for the given analytical technique.
Collapse
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.
| |
Collapse
|
6
|
Kozhikhova KV, Shilovskiy IP, Shatilov AA, Timofeeva AV, Turetskiy EA, Vishniakova LI, Nikolskii AA, Barvinskaya ED, Karthikeyan S, Smirnov VV, Kudlay DA, Andreev SM, Khaitov MR. Linear and dendrimeric antiviral peptides: design, chemical synthesis and activity against human respiratory syncytial virus. J Mater Chem B 2020; 8:2607-2617. [DOI: 10.1039/c9tb02485a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Novel artificial peptides possess anti-RSV activity through a combination of two mechanisms: direct nonspecific destabilization of the viral envelope and competitive interaction with the RSV cellular receptor.
Collapse
Affiliation(s)
| | | | - Artem A. Shatilov
- NRC Institute Immunology FMBA
- Moscow
- Russian Federation
- Sechenov First Moscow State Medical University
- Moscow
| | - Anastasiia V. Timofeeva
- NRC Institute Immunology FMBA
- Moscow
- Russian Federation
- Sechenov First Moscow State Medical University
- Moscow
| | - Evgeny A. Turetskiy
- NRC Institute Immunology FMBA
- Moscow
- Russian Federation
- Sechenov First Moscow State Medical University
- Moscow
| | | | | | | | | | - Valeriy V. Smirnov
- NRC Institute Immunology FMBA
- Moscow
- Russian Federation
- Sechenov First Moscow State Medical University
- Moscow
| | | | | | | |
Collapse
|
7
|
Shilovskiy IP, Andreev SM, Kozhikhova KV, Nikolskii AA, Khaitov MR. Prospects For the Use of Peptides against Respiratory Syncytial Virus. Mol Biol 2019. [DOI: 10.1134/s0026893319040125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
8
|
Guha S, Ghimire J, Wu E, Wimley WC. Mechanistic Landscape of Membrane-Permeabilizing Peptides. Chem Rev 2019; 119:6040-6085. [PMID: 30624911 DOI: 10.1021/acs.chemrev.8b00520] [Citation(s) in RCA: 150] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Membrane permeabilizing peptides (MPPs) are as ubiquitous as the lipid bilayer membranes they act upon. Produced by all forms of life, most membrane permeabilizing peptides are used offensively or defensively against the membranes of other organisms. Just as nature has found many uses for them, translational scientists have worked for decades to design or optimize membrane permeabilizing peptides for applications in the laboratory and in the clinic ranging from antibacterial and antiviral therapy and prophylaxis to anticancer therapeutics and drug delivery. Here, we review the field of membrane permeabilizing peptides. We discuss the diversity of their sources and structures, the systems and methods used to measure their activities, and the behaviors that are observed. We discuss the fact that "mechanism" is not a discrete or a static entity for an MPP but rather the result of a heterogeneous and dynamic ensemble of structural states that vary in response to many different experimental conditions. This has led to an almost complete lack of discrete three-dimensional active structures among the thousands of known MPPs and a lack of useful or predictive sequence-structure-function relationship rules. Ultimately, we discuss how it may be more useful to think of membrane permeabilizing peptides mechanisms as broad regions of a mechanistic landscape rather than discrete molecular processes.
Collapse
Affiliation(s)
- Shantanu Guha
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - Jenisha Ghimire
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - Eric Wu
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - William C Wimley
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| |
Collapse
|
9
|
Lyu Y, Fitriyanti M, Narsimhan G. Nucleation and growth of pores in 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) / cholesterol bilayer by antimicrobial peptides melittin, its mutants and cecropin P1. Colloids Surf B Biointerfaces 2018; 173:121-127. [PMID: 30278360 DOI: 10.1016/j.colsurfb.2018.09.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/18/2018] [Accepted: 09/20/2018] [Indexed: 10/28/2022]
Abstract
Antimicrobial peptides are one of the most promising alternatives to antibiotics for targeting pathogens without developing resistance. In this study, pore formation in 1,2-Dimyristoyl-snglycero-3-phosphocholine (DMPC) / cholesterol liposome induced by native melittin, its two mutant variants (G1I and I17 K), and cecropin P1 was investigated by monitoring the dynamics of fluorescence dye leakage. A critical peptide concentration was required for dye leakage with the rate of leakage being dependent on peptide concentration above a critical value. A lag time was required for dye leakage for low peptide concentrations that are above the critical value, which decreased at higher peptide concentrations eventually approaching zero. Lag time was found to be in the order I17 K mutant with lower hydrophobicity and higher net charge > G1I with higher hydrophobicity > melittin > cecropin P1. Cecropin P1 exhibited the highest rate of dye leakage followed by melittin, G1I, and I17 K. Size distribution and transmission electron microscopy (TEM) of liposomes exposed to peptides of different concentrations indicated pore formation with accompanied stretching of liposomes at low peptide concentrations for both melittin and cecropin P1. At much higher concentrations, however, size distribution indicated three peaks for both peptides. In both cases, TEM images show that the middle and small peaks are shown to be due to stretched liposome and broken stretched liposome respectively. For melittin, the large peak is due to peptide aggregates as well as aggregates of liposome. For cecropin P1, however, the large peak indicates cecropin P1 aggregates with solubilized lipids thus suggesting carpet mechanism.
Collapse
Affiliation(s)
- Yuan Lyu
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, United States
| | - Maya Fitriyanti
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, United States
| | - Ganesan Narsimhan
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, United States.
| |
Collapse
|
10
|
Avci FG, Akbulut BS, Ozkirimli E. Membrane Active Peptides and Their Biophysical Characterization. Biomolecules 2018; 8:biom8030077. [PMID: 30135402 PMCID: PMC6164437 DOI: 10.3390/biom8030077] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/08/2018] [Accepted: 08/13/2018] [Indexed: 12/12/2022] Open
Abstract
In the last 20 years, an increasing number of studies have been reported on membrane active peptides. These peptides exert their biological activity by interacting with the cell membrane, either to disrupt it and lead to cell lysis or to translocate through it to deliver cargos into the cell and reach their target. Membrane active peptides are attractive alternatives to currently used pharmaceuticals and the number of antimicrobial peptides (AMPs) and peptides designed for drug and gene delivery in the drug pipeline is increasing. Here, we focus on two most prominent classes of membrane active peptides; AMPs and cell-penetrating peptides (CPPs). Antimicrobial peptides are a group of membrane active peptides that disrupt the membrane integrity or inhibit the cellular functions of bacteria, virus, and fungi. Cell penetrating peptides are another group of membrane active peptides that mainly function as cargo-carriers even though they may also show antimicrobial activity. Biophysical techniques shed light on peptide–membrane interactions at higher resolution due to the advances in optics, image processing, and computational resources. Structural investigation of membrane active peptides in the presence of the membrane provides important clues on the effect of the membrane environment on peptide conformations. Live imaging techniques allow examination of peptide action at a single cell or single molecule level. In addition to these experimental biophysical techniques, molecular dynamics simulations provide clues on the peptide–lipid interactions and dynamics of the cell entry process at atomic detail. In this review, we summarize the recent advances in experimental and computational investigation of membrane active peptides with particular emphasis on two amphipathic membrane active peptides, the AMP melittin and the CPP pVEC.
Collapse
Affiliation(s)
- Fatma Gizem Avci
- Bioengineering Department, Marmara University, Kadikoy, 34722 Istanbul, Turkey.
| | | | - Elif Ozkirimli
- Chemical Engineering Department, Bogazici University, Bebek, 34342 Istanbul, Turkey.
| |
Collapse
|
11
|
Liu L, Sahu ID, Bottorf L, McCarrick RM, Lorigan GA. Investigating the Secondary Structure of Membrane Peptides Utilizing Multiple 2H-Labeled Hydrophobic Amino Acids via Electron Spin Echo Envelope Modulation (ESEEM) Spectroscopy. J Phys Chem B 2018; 122:4388-4396. [PMID: 29614227 DOI: 10.1021/acs.jpcb.7b11890] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An electron spin echo envelope modulation (ESEEM) approach was used to probe local secondary structures of membrane proteins and peptides. This ESEEM method detects dipolar couplings between 2H-labeled nuclei on the side chains of an amino acid (Leu or Val) and a strategically placed nitroxide spin-label in the proximity up to 8 Å. ESEEM spectra patterns for different samples correlate directly to the periodic structural feature of different secondary structures. Since this pattern can be affected by the side chain length and flexibility of the 2H-labeled amino acid used in the experiment, it is important to examine several different hydrophobic amino acids (d3 Ala, d8 Val, d8 Phe) utilizing this ESEEM approach. In this work, a series of ESEEM data were collected on the AChR M2δ membrane peptide to build a reference for the future application of this approach for various biological systems. The results indicate that, despite the relative intensity and signal-to-noise level, all amino acids share a similar ESEEM modulation pattern for α-helical structures. Thus, all commercially available 2H-labeled hydrophobic amino acids can be utilized as probes for the further application of this ESEEM approach. Also, the ESEEM signal intensities increase as the side chain length gets longer or less rigid. In addition, longer side chain amino acids had a larger 2H ESEEM FT peak centered at the 2H Larmor frequency for the i ± 4 sample when compared to the corresponding i ± 3 sample. For shorter side chain amino acids, the 2H ESEEM FT peak intensity ratio between i ± 4 and i ± 3 was not well-defined.
Collapse
Affiliation(s)
- Lishan Liu
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Indra D Sahu
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Lauren Bottorf
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Robert M McCarrick
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| |
Collapse
|
12
|
Basso LGM, Vicente EF, Crusca E, Cilli EM, Costa-Filho AJ. SARS-CoV fusion peptides induce membrane surface ordering and curvature. Sci Rep 2016; 6:37131. [PMID: 27892522 PMCID: PMC5125003 DOI: 10.1038/srep37131] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 10/24/2016] [Indexed: 12/23/2022] Open
Abstract
Viral membrane fusion is an orchestrated process triggered by membrane-anchored viral fusion glycoproteins. The S2 subunit of the spike glycoprotein from severe acute respiratory syndrome (SARS) coronavirus (CoV) contains internal domains called fusion peptides (FP) that play essential roles in virus entry. Although membrane fusion has been broadly studied, there are still major gaps in the molecular details of lipid rearrangements in the bilayer during fusion peptide-membrane interactions. Here we employed differential scanning calorimetry (DSC) and electron spin resonance (ESR) to gather information on the membrane fusion mechanism promoted by two putative SARS FPs. DSC data showed the peptides strongly perturb the structural integrity of anionic vesicles and support the hypothesis that the peptides generate opposing curvature stresses on phosphatidylethanolamine membranes. ESR showed that both FPs increase lipid packing and head group ordering as well as reduce the intramembrane water content for anionic membranes. Therefore, bending moment in the bilayer could be generated, promoting negative curvature. The significance of the ordering effect, membrane dehydration, changes in the curvature properties and the possible role of negatively charged phospholipids in helping to overcome the high kinetic barrier involved in the different stages of the SARS-CoV-mediated membrane fusion are discussed.
Collapse
Affiliation(s)
- Luis G M Basso
- Grupo de Biofísica Molecular Sérgio Mascarenhas, Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São-carlense, 400, Centro, São Carlos, SP, Brazil.,Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, 14040-901, Ribeirão Preto, SP, Brazil
| | - Eduardo F Vicente
- Faculdade de Ciências e Engenharia, UNESP - Univ Estadual Paulista, Campus de Tupã. Rua Domingos da Costa Lopes, 780, 17602-496, Tupã, SP, Brazil
| | - Edson Crusca
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP - Univ Estadual Paulista. Rua Prof. Franscisco Degni, 55, 14800-900, Araraquara, SP, Brazil
| | - Eduardo M Cilli
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP - Univ Estadual Paulista. Rua Prof. Franscisco Degni, 55, 14800-900, Araraquara, SP, Brazil
| | - Antonio J Costa-Filho
- Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, 14040-901, Ribeirão Preto, SP, Brazil
| |
Collapse
|
13
|
Effect of cis-(Z)-flupentixol on DPPC membranes in the presence and absence of cholesterol. Chem Phys Lipids 2016; 198:61-71. [DOI: 10.1016/j.chemphyslip.2016.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/21/2016] [Accepted: 06/02/2016] [Indexed: 12/18/2022]
|
14
|
He J, Krauson AJ, Wimley WC. Toward the de novo design of antimicrobial peptides: Lack of correlation between peptide permeabilization of lipid vesicles and antimicrobial, cytolytic, or cytotoxic activity in living cells. Biopolymers 2016; 102:1-6. [PMID: 23893525 DOI: 10.1002/bip.22281] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 04/04/2013] [Accepted: 04/19/2013] [Indexed: 11/09/2022]
Abstract
We previously performed a lipid vesicle-based, high-throughput screen on a 26-residue combinatorial peptide library that was designed de novo to yield membrane-permeabilizing peptides that fold into β-sheets. The most active and soluble library members that were identified permeabilized lipid vesicles detectably, but not with high potency. Nonetheless, they were broad-spectrum, membrane-permeabilizing antibiotics with minimum sterilizing activity at low µM concentrations. In an expansion of that work, we recently performed an iterative screen in which an active consensus sequence from that first-generation library was used as a template to design a second-generation library which was then screened against lipid vesicles at very high stringency. Compared to the consensus sequence from the first library, the most active second-generation peptides are highly potent, equilibrium pore-formers in synthetic lipid vesicles. Here, we use these first- and second-generation families of peptides to test the hypothesis that a large increase in potency in bacteria-like lipid vesicles will correlate with a large improvement in antimicrobial activity. The results do not support the hypothesis. Despite a 20-fold increase in potency against bacteria-like lipid vesicles, the second-generation peptides are only slightly more active against bacteria, and at the same time, are also more toxic against mammalian cells. The results suggest that a "pipeline" strategy toward the optimization of antimicrobial peptides could begin with a vesicle-based screen for identifying families with broad-spectrum activity, but will also need to include screening or optimization steps that are done under conditions that are more directly relevant to possible therapeutic applications.
Collapse
Affiliation(s)
- Jing He
- Department of Biochemistry SL43, Tulane University School of Medicine, New Orleans, LA, 70112
| | | | | |
Collapse
|
15
|
Leveritt JM, Pino-Angeles A, Lazaridis T. The structure of a melittin-stabilized pore. Biophys J 2016; 108:2424-2426. [PMID: 25992720 DOI: 10.1016/j.bpj.2015.04.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 04/07/2015] [Accepted: 04/09/2015] [Indexed: 11/30/2022] Open
Abstract
Melittin has been reported to form toroidal pores under certain conditions, but the atomic-resolution structure of these pores is unknown. A 9-μs all-atom molecular-dynamics simulation starting from a closely packed transmembrane melittin tetramer in DMPC shows formation of a toroidal pore after 1 μs. The pore remains stable with a roughly constant radius for the rest of the simulation. Surprisingly, one or two melittin monomers frequently transition between transmembrane and surface states. All four peptides are largely helical. A simulation in a DMPC/DMPG membrane did not lead to a stable pore, consistent with the experimentally observed lower activity of melittin on anionic membranes. The picture that emerges from this work is rather close to the classical toroidal pore, but more dynamic with respect to the configuration of the peptides.
Collapse
Affiliation(s)
- John M Leveritt
- Department of Chemistry, The City College of New York, New York, New York
| | | | - Themis Lazaridis
- Department of Chemistry, The City College of New York, New York, New York.
| |
Collapse
|
16
|
|
17
|
The membranes of Gram-negative bacteria: progress in molecular modelling and simulation. Biochem Soc Trans 2016; 43:162-7. [PMID: 25849911 DOI: 10.1042/bst20140262] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Molecular modelling and simulations have been employed to study the membranes of Gram-negative bacteria for over 20 years. Proteins native to these membranes, as well as antimicrobial peptides and drug molecules have been studied using molecular dynamics simulations in simple models of membranes, usually only comprising one lipid species. Thus, traditionally, the simulations have reflected the majority of in vitro membrane experimental setups, enabling observations from the latter to be rationalized at the molecular level. In the last few years, the sophistication and complexity of membrane models have improved considerably, such that the heterogeneity of the lipid and protein composition of the membranes can now be considered both at the atomistic and coarse-grain levels of granularity. Importantly this means relevant biology is now being retained in the models, thereby linking the in silico and in vivo scenarios. We discuss recent progress in simulations of proteins in simple lipid bilayers, more complex membrane models and finally describe some efforts to overcome timescale limitations of atomistic molecular dynamics simulations of bacterial membranes.
Collapse
|
18
|
Skalickova S, Heger Z, Krejcova L, Pekarik V, Bastl K, Janda J, Kostolansky F, Vareckova E, Zitka O, Adam V, Kizek R. Perspective of Use of Antiviral Peptides against Influenza Virus. Viruses 2015; 7:5428-42. [PMID: 26492266 PMCID: PMC4632391 DOI: 10.3390/v7102883] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 09/22/2015] [Accepted: 09/30/2015] [Indexed: 01/13/2023] Open
Abstract
The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20(th) century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides.
Collapse
Affiliation(s)
- Sylvie Skalickova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
| | - Zbynek Heger
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, Brno CZ-616 00, Czech Republic.
| | - Ludmila Krejcova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
| | - Vladimir Pekarik
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
| | - Karel Bastl
- Wool and Knitting Research Institute, Brno, Sujanovo namesti 3, Brno CZ-602 00, Czech Republic.
| | - Jozef Janda
- Laboratory of Tumour Biology, Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Libechov CZ-277 21, Czech Republic.
| | - Frantisek Kostolansky
- Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovak Republic.
| | - Eva Vareckova
- Institute of Virology, Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovak Republic.
| | - Ondrej Zitka
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, Brno CZ-616 00, Czech Republic.
| | - Vojtech Adam
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, Brno CZ-616 00, Czech Republic.
| | - Rene Kizek
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech Republic.
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, Brno CZ-616 00, Czech Republic.
| |
Collapse
|
19
|
Manukovsky N, Frydman V, Goldfarb D. Gd3+ Spin Labels Report the Conformation and Solvent Accessibility of Solution and Vesicle-Bound Melittin. J Phys Chem B 2015; 119:13732-41. [DOI: 10.1021/acs.jpcb.5b03523] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Nurit Manukovsky
- Departments of †Chemical Physics and ‡Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Veronica Frydman
- Departments of †Chemical Physics and ‡Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Daniella Goldfarb
- Departments of †Chemical Physics and ‡Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
20
|
|
21
|
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]
|
22
|
Rayahin JE, Buhrman JS, Gemeinhart RA. Melittin-glutathione S-transferase fusion protein exhibits anti-inflammatory properties and minimal toxicity. Eur J Pharm Sci 2014; 65:112-21. [PMID: 25240321 DOI: 10.1016/j.ejps.2014.09.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 09/09/2014] [Accepted: 09/10/2014] [Indexed: 12/11/2022]
Abstract
Although potent, proteins often require chemical modification for therapeutic use. Immunogenicity, difficult synthesis, and scale-up of these modifications are all engineering obstacles that stand in the way of expanding the use of these therapeutics. Melittin, a peptide derived from bee venom, has been shown to modulate inflammation. Although potentially therapeutic, the native peptide causes cell lysis and toxicity significantly hindering therapeutic application. Based upon the knowledge of the pore formation mechanism, we examined the toxicity and therapeutic effect of a melittin fusion protein with glutathione-S-transferase. The fusion of melittin and glutathione S-transferase results in diminished toxicity of the peptide and retained anti-inflammatory properties at doses that exceed toxic concentration of native melittin. Our results suggest that fusion proteins, particularly those of glutathione-S-transferase, may be facile modifications to control protein activity.
Collapse
Affiliation(s)
- Jamie E Rayahin
- Department of Biopharmaceutical Sciences, University of Illinois, Chicago, IL 60612-7231, USA
| | - Jason S Buhrman
- Department of Biopharmaceutical Sciences, University of Illinois, Chicago, IL 60612-7231, USA
| | - Richard A Gemeinhart
- Department of Biopharmaceutical Sciences, University of Illinois, Chicago, IL 60612-7231, USA; Department of Bioengineering, University of Illinois, Chicago, IL 60607-7052, USA; Department of Ophthalmology and Visual Sciences, University of Illinois, Chicago, IL 60612-4319, USA.
| |
Collapse
|
23
|
Wiedman G, Fuselier T, He J, Searson PC, Hristova K, Wimley WC. Highly efficient macromolecule-sized poration of lipid bilayers by a synthetically evolved peptide. J Am Chem Soc 2014; 136:4724-31. [PMID: 24588399 PMCID: PMC3985440 DOI: 10.1021/ja500462s] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Indexed: 12/30/2022]
Abstract
Peptides that self-assemble, at low concentration, into bilayer-spanning pores which allow the passage of macromolecules would be beneficial in multiple areas of biotechnology. However, there are few, if any, natural or designed peptides that have this property. Here we show that the 26-residue peptide "MelP5", a synthetically evolved gain-of-function variant of the bee venom lytic peptide melittin identified in a high-throughput screen for small molecule leakage, enables the passage of macromolecules across bilayers under conditions where melittin and other pore-forming peptides do not. In surface-supported bilayers, MelP5 forms unusually high conductance, equilibrium pores at peptide:lipid ratios as low as 1:25000. The increase in bilayer conductance due to MelP5 is dramatically higher, per peptide, than the increase due to the parent sequence of melittin or other peptide pore formers. Here we also develop two novel assays for macromolecule leakage from vesicles, and we use them to characterize MelP5 pores in bilayers. We show that MelP5 allows the passage of macromolecules across vesicle membranes at peptide:lipid ratios as low as 1:500, and under conditions where neither osmotic lysis nor gross vesicle destabilization occur. The macromolecule-sized, equilibrium pores formed by MelP5 are unique as neither melittin nor other pore-forming peptides release macromolecules significantly under the same conditions. MelP5 thus appears to belong to a novel functional class of peptide that could form the foundation of multiple potential biotechnological applications.
Collapse
Affiliation(s)
- Gregory Wiedman
- Department
of Materials Science and Engineering, Johns
Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for Nanobiotechnology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Taylor Fuselier
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Jing He
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Peter C. Searson
- Department
of Materials Science and Engineering, Johns
Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for Nanobiotechnology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kalina Hristova
- Department
of Materials Science and Engineering, Johns
Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for Nanobiotechnology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - William C. Wimley
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
| |
Collapse
|
24
|
Irudayam SJ, Pobandt T, Berkowitz ML. Free Energy Barrier for Melittin Reorientation from a Membrane-Bound State to a Transmembrane State. J Phys Chem B 2013; 117:13457-63. [DOI: 10.1021/jp406328d] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Sheeba J. Irudayam
- Department
of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 United States
| | - Tobias Pobandt
- Max Planck Institute of Colloids, Interfaces, Theory, Bio-Systems, Potsdam, D-14424 Germany
| | - Max L. Berkowitz
- Department
of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 United States
| |
Collapse
|
25
|
Dzuba SA. Structural studies of biological membranes using ESEEM spectroscopy of spin labels and deuterium substitution. J STRUCT CHEM+ 2013. [DOI: 10.1134/s0022476613070019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
26
|
Matalon E, Faingold O, Eisenstein M, Shai Y, Goldfarb D. The topology, in model membranes, of the core peptide derived from the T-cell receptor transmembrane domain. Chembiochem 2013; 14:1867-75. [PMID: 23881822 DOI: 10.1002/cbic.201300191] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Indexed: 01/16/2023]
Abstract
The T-cell receptor-CD3 complex (TCR-CD3) serves a critical role in protecting organisms from infectious agents. The TCR is a heterodimer composed of α- and β-chains, which are responsible for antigen recognition. Within the transmembrane domain of the α-subunit, a region has been identified to be crucial for the assembly and function of the TCR. This region, termed core peptide (CP), consists of nine amino acids (GLRILLLKV), two of which are charged (lysine and arginine) and are crucial for the interaction with CD3. Earlier studies have shown that a synthetic peptide corresponding to the CP sequence can suppress the immune response in animal models of T-cell-mediated inflammation, by disrupting proper assembly of the TCR. As a step towards the understanding of the source of the CP activity, we focused on CP in egg phosphatidylcholine/cholesterol (9:1, mol/mol) model membranes and determined its secondary structure, oligomerization state, and orientation with respect to the membrane. To achieve this goal, 15-residue segments of TCRα, containing the CP, were synthesized and spin-labeled at different locations with a nitroxide derivative. Electron spin-echo envelope modulation spectroscopy was used to probe the position and orientation of the peptides within the membrane, and double electron-electron resonance measurements were used to probe its conformation and oligomerization state. We found that the peptide is predominantly helical in a membrane environment and tends to form oligomers (mostly dimers) that are parallel to the membrane plane.
Collapse
Affiliation(s)
- Erez Matalon
- Department of Chemical Physics, Weizmann Institute of Science, 234 Hertzl St, Rehovot, 7632700 (Israel)
| | | | | | | | | |
Collapse
|
27
|
Konov K, Isaev N, Dzuba S. Glycerol penetration profile in phospholipid bilayers measured by ESEEM of spin-labelled lipids. Mol Phys 2013. [DOI: 10.1080/00268976.2013.796416] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
28
|
Multiple membrane interactions and versatile vesicle deformations elicited by melittin. Toxins (Basel) 2013; 5:637-64. [PMID: 23594437 PMCID: PMC3705284 DOI: 10.3390/toxins5040637] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/02/2013] [Accepted: 04/10/2013] [Indexed: 01/11/2023] Open
Abstract
Melittin induces various reactions in membranes and has been widely studied as a model for membrane-interacting peptide; however, the mechanism whereby melittin elicits its effects remains unclear. Here, we observed melittin-induced changes in individual giant liposomes using direct real-time imaging by dark-field optical microscopy, and the mechanisms involved were correlated with results obtained using circular dichroism, cosedimentation, fluorescence quenching of tryptophan residues, and electron microscopy. Depending on the concentration of negatively charged phospholipids in the membrane and the molecular ratio between lipid and melittin, melittin induced the “increasing membrane area”, “phased shrinkage”, or “solubilization” of liposomes. In phased shrinkage, liposomes formed small particles on their surface and rapidly decreased in size. Under conditions in which the increasing membrane area, phased shrinkage, or solubilization were mainly observed, the secondary structure of melittin was primarily estimated as an α-helix, β-like, or disordered structure, respectively. When the increasing membrane area or phased shrinkage occurred, almost all melittin was bound to the membranes and reached more hydrophobic regions of the membranes than when solubilization occurred. These results indicate that the various effects of melittin result from its ability to adopt various structures and membrane-binding states depending on the conditions.
Collapse
|
29
|
Santo KP, Irudayam SJ, Berkowitz ML. Melittin creates transient pores in a lipid bilayer: results from computer simulations. J Phys Chem B 2013; 117:5031-42. [PMID: 23534858 DOI: 10.1021/jp312328n] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To study the interaction between melittin peptides and lipid bilayer, we performed coarse-grained simulations on systems containing melittin interacting with a bilayer containing zwitterionic dipalmitoylphosphatidylcholine (DPPC) and anionic palmitoyloleoylphosphatidylglycerol (POPG) phospholipids in a 7:3 ratio. Eight different systems were considered: four at low and four at high peptide to lipid (P/L) ratios. In case of low P/L ratio we did not observe any pore creation in the bilayer. In two out of four of the simulations with the high P/L ratio, appearance of transient pores in the bilayer was observed. These pores were created due to an assembly of 3-5 melittin peptides. Not all of the peptides in the pores were in a transmembrane conformation; many of them had their termini residues anchored to the same leaflet, and these peptides assumed bent, U-shaped, conformations. We propose that when an assembly of melittin peptides creates pores, such an assembly acts as a "wedge" that splits the bilayer. To get a more detailed description of melittin on the bilayer surface and in transient pores, we performed coarse-grained to united-atom scale transformations and after that performed 50 ns molecular dynamics simulations using the united atom description of the systems. While these simulations did not show much of the change in the pore structure during the 50 ns time interval, they clearly showed the presence of water in the transient pores. The appearance of transient pores together with the translocation of peptides across the membranes is consistent with the mechanism proposed to explain graded dye leakage from large vesicles in the presence of melittin.
Collapse
Affiliation(s)
- Kolattukudy P Santo
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States
| | | | | |
Collapse
|
30
|
Matalon E, Kaminker I, Zimmermann H, Eisenstein M, Shai Y, Goldfarb D. Topology of the trans-membrane peptide WALP23 in model membranes under negative mismatch conditions. J Phys Chem B 2013; 117:2280-93. [PMID: 23311473 DOI: 10.1021/jp310056h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The organization and orientation of membrane-inserted helices is important for better understanding the mode of action of membrane-active peptides and of protein-membrane interactions. Here we report on the application of ESEEM (electron spin-echo envelope modulation) and DEER (double electron-electron resonance) techniques to probe the orientation and oligomeric state of an α-helical trans-membrane model peptide, WALP23, under conditions of negative mismatch between the hydrophobic cores of the model membrane and the peptide. Using ESEEM, we measured weak dipolar interactions between spin-labeled WALP23 and (2)H nuclei of either the solvent (D2O) or of lipids specifically deuterated at the choline group. The ESEEM data obtained from the deuterated lipids were fitted using a model that provided the spin label average distance from a layer of (2)H nuclei in the hydrophilic region of the membrane and the density of the (2)H nuclei in the layer. DEER was used to probe oligomerization through the dipolar interaction between two spin-labels on different peptides. We observed that the center of WALP23 does not coincide with the bilayer midplane and its N-terminus is more buried than the C-terminus. In addition, the ESEEM data fitting yielded a (2)H layer density that was much lower than expected. The DEER experiments revealed the presence of oligomers, the presence of which was attributable to the negative mismatch and the electrostatic dipole of the peptide. A discussion of a possible arrangement of the individual helices in the oligomers that is consistent with the ESEEM and DEER data is presented.
Collapse
Affiliation(s)
- Erez Matalon
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot, Israel 76100
| | | | | | | | | | | |
Collapse
|
31
|
Wiedman G, Herman K, Searson P, Wimley WC, Hristova K. The electrical response of bilayers to the bee venom toxin melittin: evidence for transient bilayer permeabilization. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1357-64. [PMID: 23384418 DOI: 10.1016/j.bbamem.2013.01.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 01/09/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
Abstract
Melittin is a 26-residue bee venom peptide that folds into amphipathic α-helix and causes membrane permeabilization via a mechanism that is still disputed. While an equilibrium transmembrane pore model has been a central part of the mechanistic dialogue for decades, there is growing evidence that a transmembrane pore is not required for melittin's activity. In part, the controversy is due to limited experimental tools to probe the bilayer's response to melittin. Electrochemical impedance spectroscopy (EIS) is a technique that can reveal details of molecular mechanism of peptide activity, as it yields direct, real-time measurements of membrane resistance and capacitance of supported bilayers. In this work, EIS was used in conjunction with vesicle leakage studies to characterize the response of bilayers of different lipid compositions to melittin. Experiments were carried out at low peptide to lipid ratios between 1:5000 and 1:100. The results directly demonstrate that the response of the bilayer to melittin at these concentrations cannot be explained by an equilibrium transmembrane pore model.
Collapse
Affiliation(s)
- Gregory Wiedman
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | | | | | | | | |
Collapse
|
32
|
Syryamina VN, De Zotti M, Peggion C, Formaggio F, Toniolo C, Raap J, Dzuba SA. A Molecular View on the Role of Cholesterol upon Membrane Insertion, Aggregation, and Water Accessibility of the Antibiotic Lipopeptide Trichogin GA IV As Revealed by EPR. J Phys Chem B 2012; 116:5653-60. [DOI: 10.1021/jp301660a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Victoria N. Syryamina
- Institute
of Chemical Kinetics
and Combustion, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Marta De Zotti
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Cristina Peggion
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Fernando Formaggio
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Claudio Toniolo
- ICB, Padova Unit, CNR, Department
of Chemistry, University of Padova, 35131
Padova, Italy
| | - Jan Raap
- Leiden Institute
of Chemistry,
Gorlaeus Laboratories, University of Leiden, 2300 RA Leiden, The Netherlands
| | - Sergei A. Dzuba
- Institute
of Chemical Kinetics
and Combustion, Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Department of Physics, Novosibirsk State University, 630090 Novosibirsk, Russia
| |
Collapse
|