1
|
Gamage YI, Pan J. Nanoscale Perturbations of Lipid Bilayers Induced by Magainin 2: Insights from AFM Imaging and Force Spectroscopy. Chem Phys Lipids 2024; 263:105421. [PMID: 39067642 DOI: 10.1016/j.chemphyslip.2024.105421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Revised: 07/13/2024] [Accepted: 07/25/2024] [Indexed: 07/30/2024]
Abstract
This study explores the impact of the antimicrobial peptide magainin 2 (Mag2) on lipid bilayers with varying compositions. We employed high-resolution atomic force microscopy (AFM) to reveal a dynamic spectrum of structural changes induced by Mag2. Our AFM imaging unveiled distinct structural alterations in zwitterionic POPC bilayers upon Mag2 exposure, notably the formation of nanoscale depressions within the bilayer surface, which we term as "surface pores" to differentiate them from transmembrane pores. These surface pores are characterized by a limited depth that does not appear to fully traverse the bilayer and reach the opposing leaflet. Additionally, our AFM-based force spectroscopy investigation on POPC bilayers revealed a reduction in bilayer puncture force (FP) and Young's modulus (E) upon Mag2 interaction, indicating a weakening of bilayer stability and increased flexibility, which may facilitate peptide insertion. The inclusion of anionic POPG into POPC bilayers elucidated its modulatory effects on Mag2 activity, highlighting the role of lipid composition in peptide-bilayer interactions. In contrast to surface pores, Mag2 treatment of E. coli total lipid extract bilayers resulted in increased surface roughness, which we describe as a fluctuation-like morphology. We speculate that the weaker cohesive interactions between heterogeneous lipids in E. coli bilayers may render them more susceptible to Mag2-induced perturbations. This could lead to widespread disruptions manifested as surface fluctuations throughout the bilayer, rather than the formation of well-defined pores. Together, our findings of nanoscale bilayer perturbations provide useful insights into the molecular mechanisms governing Mag2-membrane interactions.
Collapse
Affiliation(s)
| | - Jianjun Pan
- Department of Physics, University of South Florida, Tampa, FL 33620, United States.
| |
Collapse
|
2
|
Aryal CM, Bui NN, Song L, Pan J. The N-terminal helices of amphiphysin and endophilin have different capabilities of membrane remodeling. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183907. [PMID: 35247332 DOI: 10.1016/j.bbamem.2022.183907] [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: 09/13/2021] [Revised: 02/17/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
Amphiphysin and endophilin are two members of the N-BAR protein family. We have reported membrane interactions of the helix 0 of endophilin (H0-Endo). Here we investigate membrane modulations caused by the helix 0 of amphiphysin (H0-Amph). Electron paramagnetic resonance (EPR) spectroscopy was used to explore membrane properties. H0-Amph was found to reduce lipid mobility, make the membrane interior more polar, and decrease lipid chain orientational order. The EPR data also showed that for anionic membranes, H0-Endo acted as a more potent modulator. For instance, at peptide-to-lipid (P/L) ratio of 1/20, the peak-to-peak splitting was increased by 0.27 G and 1.89 G by H0-Amph and H0-Endo, respectively. Similarly, H0-Endo caused a larger change in the bilayer polarity than H0-Amph (30% versus 12% at P/L = 1/20). At P/L = 1/50, the chain orientational order was decreased by 26% and 66% by H0-Amph and H0-Endo, respectively. The different capabilities were explained by considering hydrophobicity score distributions. We employed atomic force microscopy to investigate membrane structural changes. Both peptides caused the formation of micron-sized holes. Interestingly, only H0-Amph induced membrane fusion as evidenced by the formation of high-rise regions. Lastly, experiments of giant unilamellar vesicles showed that H0-Amph and H0-Endo generated thin tubules and miniscule vesicles, respectively. Together, our studies showed that both helices are effective in altering membrane properties; the observed changes might be important for membrane curvature induction. Importantly, comparisons between the two peptides revealed that the degree of membrane remodeling is dependent on the sequence of the N-terminal helix of the N-BAR protein family.
Collapse
Affiliation(s)
- Chinta M Aryal
- Department of Physics, University of South Florida, Tampa, FL 33620, United States of America; MED-Cancer & Cell Biology, University of Cincinnati, Cincinnati, OH 45267
| | - Nhat Nguyen Bui
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America
| | - Likai Song
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America.
| | - Jianjun Pan
- Department of Physics, University of South Florida, Tampa, FL 33620, United States of America.
| |
Collapse
|
3
|
Aryal CM, Bui NN, Khadka NK, Song L, Pan J. The helix 0 of endophilin modifies membrane material properties and induces local curvature. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183397. [PMID: 32533976 DOI: 10.1016/j.bbamem.2020.183397] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 06/04/2020] [Accepted: 06/09/2020] [Indexed: 11/26/2022]
Abstract
The amphipathic helix 0 of endophilin (i.e., H0-Endo) is important to membrane binding, but its function of curvature generation remains controversial. We used electron paramagnetic resonance (EPR) spectroscopy to study effects of H0-Endo on membrane material properties. We found that H0-Endo reduced lipid chain mobility and increased bilayer polarity, i.e., making the bilayer interior more polar. Lipid-dependent examination revealed that anionic lipids augmented the effect of H0-Endo, while cholesterol had a minimal impact. Our EPR spectroscopy of magnetically aligned bicelles showed that as the peptide-to-lipid ratio increased, the lipid chain orientational order decreased gradually, followed by a sudden loss. We discuss an interfacial-bound model of the amphipathic H0-Endo to account for all EPR data. We used atomic force microscopy and fluorescence microscopy to explore membrane morphological changes. We found that H0-Endo caused the formation of micron-sized holes in mica-supported planar bilayers. Hole formation is likely caused by two competing forces - the adhesion force exerted by the substrate represses bilayer budging, whereas the line tension originating from peptide clustering has a tendency of destabilizing bilayer organization. In the absence of substrate influences, membrane curvature induction was manifested by generating small vesicles surrounding giant unilamellar vesicles. Our results of membrane perforation and vesiculation suggest that the functionality of H0-Endo is more than just coordinating membrane binding of endophilin.
Collapse
Affiliation(s)
- Chinta M Aryal
- Department of Physics, University of South Florida, Tampa, FL 33620, United States of America
| | - Nhat Nguyen Bui
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America
| | - Nawal K Khadka
- Department of Physics, University of South Florida, Tampa, FL 33620, United States of America
| | - Likai Song
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America.
| | - Jianjun Pan
- Department of Physics, University of South Florida, Tampa, FL 33620, United States of America.
| |
Collapse
|
4
|
Salnikov ES, De Zotti M, Bobone S, Mazzuca C, Raya J, Siano AS, Peggion C, Toniolo C, Stella L, Bechinger B. Trichogin GA IV Alignment and Oligomerization in Phospholipid Bilayers. Chembiochem 2019; 20:2141-2150. [PMID: 31125169 DOI: 10.1002/cbic.201900263] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Indexed: 12/21/2022]
Abstract
Trichogin GA IV is a short peptaibol with antimicrobial activity. This uncharged, but amphipathic, sequence is aligned at the membrane interface and undergoes a transition to an aggregated state that inserts more deeply into the membrane, an assembly that predominates at a peptide-to-lipid ratio (P/L) of 1:20. In this work, the natural trichogin sequence was prepared and reconstituted into oriented lipid bilayers. The 15 N NMR chemical shift is indicative of a well-defined alignment of the peptide parallel to the membrane surface at P/Ls of 1:120 and 1:20. When the P/L is increased to 1:8, an additional peptide topology is observed that is indicative of a heterogeneous orientation, with helix alignments ranging from around the magic angle to perfectly in-plane. The topological preference of the trichogin helix for an orientation parallel to the membrane surface was confirmed by attenuated total reflection FTIR spectroscopy. Furthermore, 19 F CODEX experiments were performed on a trichogin sequence with 19 F-Phe at position 10. The CODEX decay is in agreement with a tetrameric complex, in which the 19 F sites are about 9-9.5 Å apart. Thus, a model emerges in which the monomeric peptide aligns along the membrane surface. When the peptide concentration increases, first dimeric and then tetrameric assemblies form, made up from helices oriented predominantly parallel to the membrane surface. The formation of these aggregates correlates with the release of vesicle contents including relatively large molecules.
Collapse
Affiliation(s)
- Evgeniy S Salnikov
- Institut de Chimie, University of Strasbourg, CNRS, UMR 7177, 4, rue Blaise Pascal, 67070, Strasbourg, France
| | - Marta De Zotti
- ICB, Padova Unit, CNR', Department of Chemistry, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Sara Bobone
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Claudia Mazzuca
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Jesus Raya
- Institut de Chimie, University of Strasbourg, CNRS, UMR 7177, 4, rue Blaise Pascal, 67070, Strasbourg, France
| | - Alvaro S Siano
- Departamento de Química Organica, Facultad de Bioquímica y Ciencias Biologicas, Universidad Nacional del Litoral, Ciudad Universitaria UNL, Ruta Nacional N° 168, Km 472, Santa Fe, 3000, Argentina
| | - Cristina Peggion
- ICB, Padova Unit, CNR', Department of Chemistry, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Claudio Toniolo
- ICB, Padova Unit, CNR', Department of Chemistry, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Lorenzo Stella
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Burkhard Bechinger
- Institut de Chimie, University of Strasbourg, CNRS, UMR 7177, 4, rue Blaise Pascal, 67070, Strasbourg, France
| |
Collapse
|
5
|
Aisenbrey C, Marquette A, Bechinger B. The Mechanisms of Action of Cationic Antimicrobial Peptides Refined by Novel Concepts from Biophysical Investigations. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1117:33-64. [PMID: 30980352 DOI: 10.1007/978-981-13-3588-4_4] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Even 30 years after the discovery of magainins, biophysical and structural investigations on how these peptides interact with membranes can still bear surprises and add new interesting detail to how these peptides exert their antimicrobial action. Early on, using oriented solid-state NMR spectroscopy, it was found that the amphipathic helices formed by magainins are active when being oriented parallel to the membrane surface. More recent investigations indicate that this in-planar alignment is also found when PGLa and magainin in combination exert synergistic pore-forming activities, where studies on the mechanism of synergistic interaction are ongoing. In a related manner, the investigation of dimeric antimicrobial peptide sequences has become an interesting topic of research which bears promise to refine our views how antimicrobial action occurs. The molecular shape concept has been introduced to explain the effects of lipids and peptides on membrane morphology, locally and globally, and in particular of cationic amphipathic helices that partition into the membrane interface. This concept has been extended in this review to include more recent ideas on soft membranes that can adapt to external stimuli including membrane-disruptive molecules. In this manner, the lipids can change their shape in the presence of low peptide concentrations, thereby maintaining the bilayer properties. At higher peptide concentrations, phase transitions occur which lead to the formation of pores and membrane lytic processes. In the context of the molecular shape concept, the properties of lipopeptides, including surfactins, are shortly presented, and comparisons with the hydrophobic alamethicin sequence are made.
Collapse
Affiliation(s)
| | - Arnaud Marquette
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, Strasbourg, France
| | - Burkhard Bechinger
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, Strasbourg, France. .,Faculté de chimie, Institut le Bel, Strasbourg, France.
| |
Collapse
|
6
|
Afanasyeva EF, Syryamina VN, De Zotti M, Formaggio F, Toniolo C, Dzuba SA. Peptide antibiotic trichogin in model membranes: Self-association and capture of fatty acids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1861:524-531. [PMID: 30550880 DOI: 10.1016/j.bbamem.2018.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 10/27/2022]
Abstract
The antimicrobial action of peptides in bacterial membranes is commonly related to their mode of self-assembling which results in pore formation. To optimize peptide antibiotic use for therapeutic purposes, a study on the concentration dependence of self-assembling process is thus desirable. In this work, we investigate this dependence for peptaibol trichogin GA IV (Tric) in the 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) model membrane in the range of peptide concentrations between 0.5 and 3.3 mol%. Pulsed double electron-electron resonance (PELDOR) applied on spin-labeled peptide analogs highlights the onset of peptide dimerization above a critical peptide concentration value, namely ~ 2 mol%. Electron spin echo (ESE) envelope modulation (ESEEM) for D2O-hydrated bilayers shows that dimerization is accompanied by peptide re-orientation towards a trans-membrane disposition. For spin-labeled stearic acids (5-DSA) in POPC bilayers, the study of ESE decays and ESEEM in the presence of a deuterated peptide analog indicates that above the critical peptide concentration the 5-DSA molecules are attracted by peptide molecules, forming nanoclusters. As the 5-DSA molecules represent a model for the behavior of fatty acids participating in bacterial membrane homeostasis, such capturing action by Tric may represent an additional mechanism of its antibiotic activity.
Collapse
Affiliation(s)
- Ekaterina F Afanasyeva
- Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation; Novosibirsk State University, Novosibirsk 630090, Russian Federation
| | - Victoria N Syryamina
- Institute of Chemical Kinetics and Combustion, RAS, Novosibirsk 630090, Russian Federation; Novosibirsk State University, Novosibirsk 630090, Russian Federation
| | - Marta De Zotti
- Department of Chemical Sciences, University of Padova, 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
| | - Claudio Toniolo
- 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; Novosibirsk State University, Novosibirsk 630090, Russian Federation.
| |
Collapse
|
7
|
Das S, Ben Haj Salah K, Djibo M, Inguimbert N. Peptaibols as a model for the insertions of chemical modifications. Arch Biochem Biophys 2018; 658:16-30. [DOI: 10.1016/j.abb.2018.09.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/05/2018] [Accepted: 09/18/2018] [Indexed: 12/13/2022]
|
8
|
Pan J, Dalzini A, Khadka NK, Aryal CM, Song L. Lipid Extraction by α-Synuclein Generates Semi-Transmembrane Defects and Lipoprotein Nanoparticles. ACS OMEGA 2018; 3:9586-9597. [PMID: 30198000 PMCID: PMC6120733 DOI: 10.1021/acsomega.8b01462] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 08/07/2018] [Indexed: 05/17/2023]
Abstract
Modulations of synaptic membranes play an essential role in the physiological and pathological functions of the presynaptic protein α-synuclein (αSyn). Here we used solution atomic force microscopy (AFM) and electron paramagnetic resonance (EPR) spectroscopy to investigate membrane modulations caused by αSyn. We used several lipid bilayers to explore how different lipid species may regulate αSyn-membrane interactions. We found that at a protein-to-lipid ratio of ∼1/9, αSyn perturbed lipid bilayers by generating semi-transmembrane defects that only span one leaflet. In addition, αSyn coaggregates with lipid molecules to produce ∼10 nm-sized lipoprotein nanoparticles. The obtained AFM data are consistent with the apolipoprotein characteristic of αSyn. The role of anionic lipids was elucidated by comparing results from zwitterionic and anionic lipid bilayers. Specifically, our AFM measurements showed that anionic bilayers had a larger tendency of forming bilayer defects; similarly, our EPR measurements revealed that anionic bilayers exhibited more substantial changes in lipid chain mobility and bilayer polarity. We also studied the effect of cholesterol. We found that cholesterol increased the capability of αSyn in inducing bilayer defects and altering lipid chain mobility and bilayer polarity. These data can be explained by an increase in the lipid headgroup-headgroup spacing and/or specific cholesterol-αSyn interactions. Interestingly, we found an inhibitory effect of the cone-shaped phosphatidylethanolamine lipids on αSyn-induced bilayer remodeling. We explained our data by considering interlipid hydrogen-bonding that can stabilize bilayer organization and suppress lipid extraction. Our results of lipid-dependent membrane modulations are likely relevant to αSyn functioning.
Collapse
Affiliation(s)
- Jianjun Pan
- Department
of Physics, University of South Florida, Tampa, Florida 33620, United States
- E-mail: (J.P.)
| | - Annalisa Dalzini
- National
High Magnetic Field Laboratory, Florida
State University, Tallahassee, Florida 32310, United States
| | - Nawal K. Khadka
- Department
of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Chinta M. Aryal
- Department
of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Likai Song
- National
High Magnetic Field Laboratory, Florida
State University, Tallahassee, Florida 32310, United States
- E-mail: (L.S.)
| |
Collapse
|
9
|
Cholesterol and phosphatidylethanolamine lipids exert opposite effects on membrane modulations caused by the M2 amphipathic helix. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1861:201-209. [PMID: 30071193 DOI: 10.1016/j.bbamem.2018.07.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/12/2018] [Accepted: 07/25/2018] [Indexed: 12/18/2022]
Abstract
Membrane curvature remodeling induced by amphipathic helices (AHs) is essential in many biological processes. Here we studied a model amphipathic peptide, M2AH, derived from influenza A M2. We are interested in how M2AH may promote membrane curvature by altering membrane physical properties. We used atomic force microscopy (AFM) to examine changes in membrane topographic and mechanical properties. We used electron paramagnetic resonance (EPR) spectroscopy to explore changes in lipid chain mobility and chain orientational order. We found that M2AH perturbed lipid bilayers by generating nanoscale pits. The structural data are consistent with lateral expansion of lipid chain packing, resulting in a mechanically weaker bilayer. Our EPR spectroscopy showed that M2AH reduced lipid chain mobility and had a minimal effect on lipid chain orientational order. The EPR data are consistent with the surface-bound state of M2AH that acts as a chain mobility inhibitor. By comparing results from different lipid bilayers, we found that cholesterol enhanced the activity of M2AH in inducing bilayer pits and altering lipid chain mobility. The results were explained by considering specific M2AH-cholesterol recognition and/or cholesterol-induced expansion of interlipid distance. Both AFM and EPR experiments revealed a modest effect of anionic lipids. This highlights that membrane interaction of M2AH is mainly driven by hydrophobic forces. Lastly, we found that phosphatidylethanolamine (PE) lipids inhibited the activity of M2AH. We explained our data by considering interlipid hydrogen-bonding that can stabilize bilayer organization. Our results of lipid-dependent membrane modulations are likely relevant to M2AH-induced membrane restructuring.
Collapse
|
10
|
Marquette A, Bechinger B. Biophysical Investigations Elucidating the Mechanisms of Action of Antimicrobial Peptides and Their Synergism. Biomolecules 2018; 8:E18. [PMID: 29670065 PMCID: PMC6023007 DOI: 10.3390/biom8020018] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 01/30/2023] Open
Abstract
Biophysical and structural investigations are presented with a focus on the membrane lipid interactions of cationic linear antibiotic peptides such as magainin, PGLa, LL37, and melittin. Observations made with these peptides are distinct as seen from data obtained with the hydrophobic peptide alamethicin. The cationic amphipathic peptides predominantly adopt membrane alignments parallel to the bilayer surface; thus the distribution of polar and non-polar side chains of the amphipathic helices mirror the environmental changes at the membrane interface. Such a membrane partitioning of an amphipathic helix has been shown to cause considerable disruptions in the lipid packing arrangements, transient openings at low peptide concentration, and membrane disintegration at higher peptide-to-lipid ratios. The manifold supramolecular arrangements adopted by lipids and peptides are represented by the 'soft membranes adapt and respond, also transiently' (SMART) model. Whereas molecular dynamics simulations provide atomistic views on lipid membranes in the presence of antimicrobial peptides, the biophysical investigations reveal interesting details on a molecular and supramolecular level, and recent microscopic imaging experiments delineate interesting sequences of events when bacterial cells are exposed to such peptides. Finally, biophysical studies that aim to reveal the mechanisms of synergistic interactions of magainin 2 and PGLa are presented, including unpublished isothermal titration calorimetry (ITC), circular dichroism (CD) and dynamic light scattering (DLS) measurements that suggest that the peptides are involved in liposome agglutination by mediating intermembrane interactions. A number of structural events are presented in schematic models that relate to the antimicrobial and synergistic mechanism of amphipathic peptides when they are aligned parallel to the membrane surface.
Collapse
Affiliation(s)
- Arnaud Marquette
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 4, rue Blaise Pascal, 67070 Strasbourg, France.
| | - Burkhard Bechinger
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 4, rue Blaise Pascal, 67070 Strasbourg, France.
| |
Collapse
|
11
|
Biondi B, Peggion C, De Zotti M, Pignaffo C, Dalzini A, Bortolus M, Oancea S, Hilma G, Bortolotti A, Stella L, Pedersen JZ, Syryamina VN, Tsvetkov YD, Dzuba SA, Toniolo C, Formaggio F. Conformational properties, membrane interaction, and antibacterial activity of the peptaibiotic chalciporin A: Multitechnique spectroscopic and biophysical investigations on the natural compound and labeled analogs. Biopolymers 2017; 110. [PMID: 29127716 DOI: 10.1002/bip.23083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 10/06/2017] [Accepted: 10/15/2017] [Indexed: 02/28/2024]
Abstract
In this work, an extensive set of spectroscopic and biophysical techniques (including FT-IR absorption, CD, 2D-NMR, fluorescence, and CW/PELDOR EPR) was used to study the conformational preferences, membrane interaction, and bioactivity properties of the naturally occurring synthetic 14-mer peptaibiotic chalciporin A, characterized by a relatively low (≈20%), uncommon proportion of the strongly helicogenic Aib residue. In addition to the unlabeled peptide, we gained in-depth information from the study of two labeled analogs, characterized by one or two residues of the helicogenic, nitroxyl radical-containing TOAC. All three compounds were prepared using the SPPS methodology, which was carefully modified in the course of the syntheses of TOAC-labeled analogs in view of the poorly reactive α-amino function of this very bulky residue and the specific requirements of its free-radical side chain. Despite its potentially high flexibility, our results point to a predominant, partly amphiphilic, α-helical conformation for this peptaibiotic. Therefore, not surprisingly, we found an effective membrane affinity and a remarkable penetration propensity. However, chalciporin A exhibits a selectivity in its antibacterial activity not in agreement with that typical of the other members of this peptide class.
Collapse
Affiliation(s)
- Barbara Biondi
- Institute of Biomolecular, Chemistry, Padova Unit, CNR, Padova, 35131, Italy
| | - Cristina Peggion
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| | - Marta De Zotti
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| | - Chiara Pignaffo
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| | - Annalisa Dalzini
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| | - Marco Bortolus
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| | - Simona Oancea
- Department of Agricultural Sciences and Food Engineering, "Lucian Blaga" University of Sibiu, Sibiu, 550012, Romania
| | - Geta Hilma
- Department of Medicine, "Lucian Blaga" University of Sibiu, Sibiu, 550012, Romania
| | - Annalisa Bortolotti
- Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Rome, 00133, Italy
| | - Lorenzo Stella
- Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Rome, 00133, Italy
| | - Jens Z Pedersen
- Department of Biology, University of Rome Tor Vergata, Rome, 00133, Italy
| | - Victoria N Syryamina
- Institute of Chemical Kinetics and Combustion, Novosibirsk, 630090, Russian Federation
| | - Yuri D Tsvetkov
- Institute of Chemical Kinetics and Combustion, Novosibirsk, 630090, Russian Federation
| | - Sergei A Dzuba
- Institute of Chemical Kinetics and Combustion, Novosibirsk, 630090, Russian Federation
| | - Claudio Toniolo
- Institute of Biomolecular, Chemistry, Padova Unit, CNR, Padova, 35131, Italy
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| | - Fernando Formaggio
- Institute of Biomolecular, Chemistry, Padova Unit, CNR, Padova, 35131, Italy
- Department of Chemical Sciences, University of Padova, Padova, 35131, Italy
| |
Collapse
|
12
|
Pan J, Sahoo PK, Dalzini A, Hayati Z, Aryal CM, Teng P, Cai J, Gutierrez HR, Song L. Membrane Disruption Mechanism of a Prion Peptide (106-126) Investigated by Atomic Force Microscopy, Raman and Electron Paramagnetic Resonance Spectroscopy. J Phys Chem B 2017; 121:5058-5071. [PMID: 28459565 PMCID: PMC5770145 DOI: 10.1021/acs.jpcb.7b02772] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A fragment of the human prion protein spanning residues 106-126 (PrP106-126) recapitulates many essential properties of the disease-causing protein such as amyloidogenicity and cytotoxicity. PrP106-126 has an amphipathic characteristic that resembles many antimicrobial peptides (AMPs). Therefore, the toxic effect of PrP106-126 could arise from a direct association of monomeric peptides with the membrane matrix. Several experimental approaches are employed to scrutinize the impacts of monomeric PrP106-126 on model lipid membranes. Porous defects in planar bilayers are observed by using solution atomic force microscopy. Adding cholesterol does not impede defect formation. A force spectroscopy experiment shows that PrP106-126 reduces Young's modulus of planar lipid bilayers. We use Raman microspectroscopy to study the effect of PrP106-126 on lipid atomic vibrational dynamics. For phosphatidylcholine lipids, PrP106-126 disorders the intrachain conformation, while the interchain interaction is not altered; for phosphatidylethanolamine lipids, PrP106-126 increases the interchain interaction, while the intrachain conformational order remains similar. We explain the observed differences by considering different modes of peptide insertion. Finally, electron paramagnetic resonance spectroscopy shows that PrP106-126 progressively decreases the orientational order of lipid acyl chains in magnetically aligned bicelles. Together, our experimental data support the proposition that monomeric PrP106-126 can disrupt lipid membranes by using similar mechanisms found in AMPs.
Collapse
Affiliation(s)
- Jianjun Pan
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Prasana K. Sahoo
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Annalisa Dalzini
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Zahra Hayati
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Chinta M. Aryal
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Peng Teng
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Jianfeng Cai
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | | | - Likai Song
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| |
Collapse
|
13
|
Bortolus M, Dalzini A, Maniero AL, Panighel G, Siano A, Toniolo C, De Zotti M, Formaggio F. Insights into peptide-membrane interactions of newly synthesized, nitroxide-containing analogs of the peptaibiotic trichogin GAIV using EPR. Biopolymers 2017; 108. [DOI: 10.1002/bip.22913] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 06/21/2016] [Accepted: 06/29/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Marco Bortolus
- Department of Chemistry; University of Padova; Padova 35131 Italy
| | - Annalisa Dalzini
- Department of Chemistry; University of Padova; Padova 35131 Italy
| | | | - Giacomo Panighel
- Department of Chemistry; University of Padova; Padova 35131 Italy
| | - Alvaro Siano
- Department of Chemistry; University of Padova; Padova 35131 Italy
- Departamento de Química Orgánica; Facultad de Bioquímica y Ciencias Biológicas (FBCB), Universidad Nacional del Litoral (UNL); 3000 Santa Fe Argentina
| | - Claudio Toniolo
- Department of Chemistry; University of Padova; Padova 35131 Italy
- Institute of Biomolecular Chemistry, Padova Unit, CNR; Padova 35131 Italy
| | - Marta De Zotti
- Department of Chemistry; University of Padova; Padova 35131 Italy
| | - Fernando Formaggio
- Department of Chemistry; University of Padova; Padova 35131 Italy
- Institute of Biomolecular Chemistry, Padova Unit, CNR; Padova 35131 Italy
| |
Collapse
|
14
|
Dalzini A, Bergamini C, Biondi B, De Zotti M, Panighel G, Fato R, Peggion C, Bortolus M, Maniero AL. The rational search for selective anticancer derivatives of the peptide Trichogin GA IV: a multi-technique biophysical approach. Sci Rep 2016; 6:24000. [PMID: 27039838 PMCID: PMC4819177 DOI: 10.1038/srep24000] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/18/2016] [Indexed: 02/07/2023] Open
Abstract
Peptaibols are peculiar peptides produced by fungi as weapons against other microorganisms. Previous studies showed that peptaibols are promising peptide-based drugs because they act against cell membranes rather than a specific target, thus lowering the possibility of the onset of multi-drug resistance, and they possess non-coded α-amino acid residues that confer proteolytic resistance. Trichogin GA IV (TG) is a short peptaibol displaying antimicrobial and cytotoxic activity. In the present work, we studied thirteen TG analogues, adopting a multidisciplinary approach. We showed that the cytotoxicity is tuneable by single amino-acids substitutions. Many analogues maintain the same level of non-selective cytotoxicity of TG and three analogues are completely non-toxic. Two promising lead compounds, characterized by the introduction of a positively charged unnatural amino-acid in the hydrophobic face of the helix, selectively kill T67 cancer cells without affecting healthy cells. To explain the determinants of the cytotoxicity, we investigated the structural parameters of the peptides, their cell-binding properties, cell localization, and dynamics in the membrane, as well as the cell membrane composition. We show that, while cytotoxicity is governed by the fine balance between the amphipathicity and hydrophobicity, the selectivity depends also on the expression of negatively charged phospholipids on the cell surface.
Collapse
Affiliation(s)
- Annalisa Dalzini
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy
| | - Christian Bergamini
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna, via Irnerio 48, 40126, Bologna, Italy
| | - Barbara Biondi
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy
| | - Marta De Zotti
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy
| | - Giacomo Panighel
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy
| | - Romana Fato
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna, via Irnerio 48, 40126, Bologna, Italy
| | - Cristina Peggion
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy
| | - Marco Bortolus
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy.,Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, 20126, Milano, Italy
| | - Anna Lisa Maniero
- Dipartimento di Chimica, Università di Padova, via Marzolo 1, 35131, Padova, Italy
| |
Collapse
|
15
|
Peptaibolin analogues by incorporation of α,α-dialkylglycines: synthesis and study of their membrane permeating ability. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.12.079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
16
|
Bortolus M, Dalzini A, Formaggio F, Toniolo C, Gobbo M, Maniero AL. An EPR study of ampullosporin A, a medium-length peptaibiotic, in bicelles and vesicles. Phys Chem Chem Phys 2016; 18:749-60. [DOI: 10.1039/c5cp04136h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
EPR/CD spectroscopies reveal that the peptaibol ampullosporin A changes the orientation and conformation depending on its concentration and bilayer thickness.
Collapse
Affiliation(s)
- Marco Bortolus
- Dipartimento di Scienze Chimiche
- Università degli Studi di Padova
- 35131 Padova
- Italy
- Dipartimento di Scienza dei Materiali
| | - Annalisa Dalzini
- Dipartimento di Scienze Chimiche
- Università degli Studi di Padova
- 35131 Padova
- Italy
| | - Fernando Formaggio
- Dipartimento di Scienze Chimiche
- Università degli Studi di Padova
- 35131 Padova
- Italy
| | - Claudio Toniolo
- Dipartimento di Scienze Chimiche
- Università degli Studi di Padova
- 35131 Padova
- Italy
| | - Marina Gobbo
- Dipartimento di Scienze Chimiche
- Università degli Studi di Padova
- 35131 Padova
- Italy
| | - Anna Lisa Maniero
- Dipartimento di Scienze Chimiche
- Università degli Studi di Padova
- 35131 Padova
- Italy
| |
Collapse
|
17
|
Bobone S, De Zotti M, Bortolotti A, Biondi B, Ballano G, Palleschi A, Toniolo C, Formaggio F, Stella L. The fluorescence and infrared absorption probepara-cyanophenylalanine: Effect of labeling on the behavior of different membrane-interacting peptides. Biopolymers 2015; 104:521-32. [DOI: 10.1002/bip.22674] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 04/30/2015] [Accepted: 05/04/2015] [Indexed: 12/18/2022]
Affiliation(s)
- Sara Bobone
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; 00133 Rome Italy
| | - Marta De Zotti
- Department of Chemistry; University of Padova; 35131 Padova Italy
| | - Annalisa Bortolotti
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; 00133 Rome Italy
| | - Barbara Biondi
- Institute of Biomolecular Chemistry, Padova Unit, CNR; 35131 Padova Italy
| | - Gema Ballano
- Department of Chemistry; University of Padova; 35131 Padova Italy
| | - Antonio Palleschi
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; 00133 Rome Italy
| | - Claudio Toniolo
- Department of Chemistry; University of Padova; 35131 Padova Italy
- Institute of Biomolecular Chemistry, Padova Unit, CNR; 35131 Padova Italy
| | - Fernando Formaggio
- Department of Chemistry; University of Padova; 35131 Padova Italy
- Institute of Biomolecular Chemistry, Padova Unit, CNR; 35131 Padova Italy
| | - Lorenzo Stella
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; 00133 Rome Italy
| |
Collapse
|
18
|
Gallaher WR, Garry RF. Modeling of the Ebola virus delta peptide reveals a potential lytic sequence motif. Viruses 2015; 7:285-305. [PMID: 25609303 PMCID: PMC4306839 DOI: 10.3390/v7010285] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/12/2015] [Accepted: 01/16/2015] [Indexed: 12/24/2022] Open
Abstract
Filoviruses, such as Ebola and Marburg viruses, cause severe outbreaks of human infection, including the extensive epidemic of Ebola virus disease (EVD) in West Africa in 2014. In the course of examining mutations in the glycoprotein gene associated with 2014 Ebola virus (EBOV) sequences, a differential level of conservation was noted between the soluble form of glycoprotein (sGP) and the full length glycoprotein (GP), which are both encoded by the GP gene via RNA editing. In the region of the proteins encoded after the RNA editing site sGP was more conserved than the overlapping region of GP when compared to a distant outlier species, Tai Forest ebolavirus. Half of the amino acids comprising the “delta peptide”, a 40 amino acid carboxy-terminal fragment of sGP, were identical between otherwise widely divergent species. A lysine-rich amphipathic peptide motif was noted at the carboxyl terminus of delta peptide with high structural relatedness to the cytolytic peptide of the non-structural protein 4 (NSP4) of rotavirus. EBOV delta peptide is a candidate viroporin, a cationic pore-forming peptide, and may contribute to EBOV pathogenesis.
Collapse
Affiliation(s)
- William R Gallaher
- Mockingbird Nature Research Group, PO Box 568, Pearl River, LA 70452, USA.
| | - Robert F Garry
- Department of Microbiology and Immunology, Tulane University Medical Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
| |
Collapse
|
19
|
Mobbili G, Crucianelli E, Barbon A, Marcaccio M, Pisani M, Dalzini A, Ussano E, Bortolus M, Stipa P, Astolfi P. Liponitroxides: EPR study and their efficacy as antioxidants in lipid membranes. RSC Adv 2015. [DOI: 10.1039/c5ra18963b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fighting lipid peroxidation on its own ground: the antioxidant activity of new synthesized lipid-functionalized nitroxides is maximized in the PUFA region and correlates with the nitroxide location within the lipid bilayer as found by EPR spectroscopy.
Collapse
Affiliation(s)
- Giovanna Mobbili
- Department of Life and Environmental Sciences
- Università Politecnica delle Marche
- I-60131 Ancona
- Italy
| | - Emanuela Crucianelli
- Department of Life and Environmental Sciences
- Università Politecnica delle Marche
- I-60131 Ancona
- Italy
| | - Antonio Barbon
- Department of Chemical Sciences
- Università di Padova
- I-35131 Padova
- Italy
| | - Massimo Marcaccio
- Department of Chemistry “G. Ciamician”
- Università di Bologna
- I-40126 Bologna
- Italy
| | - Michela Pisani
- Department of Materials
- Environmental Sciences and Urban Planning
- Università Politecnica delle Marche
- I-60131 Ancona
- Italy
| | - Annalisa Dalzini
- Department of Chemical Sciences
- Università di Padova
- I-35131 Padova
- Italy
| | - Eleonora Ussano
- Department of Chemistry “G. Ciamician”
- Università di Bologna
- I-40126 Bologna
- Italy
| | - Marco Bortolus
- Department of Chemical Sciences
- Università di Padova
- I-35131 Padova
- Italy
- Department of Material Sciences
| | - Pierluigi Stipa
- Department of Materials
- Environmental Sciences and Urban Planning
- Università Politecnica delle Marche
- I-60131 Ancona
- Italy
| | - Paola Astolfi
- Department of Materials
- Environmental Sciences and Urban Planning
- Università Politecnica delle Marche
- I-60131 Ancona
- Italy
| |
Collapse
|