1
|
Hu X, Liao M, Shen K, Ding K, Campana M, van der Kamp S, McInnes EF, Padia F, Lu JR. Unraveling How Membrane Nanostructure Changes Impact the Eye Irritation of Nonionic Alkyl Ethoxylate Surfactants. ACS APPLIED MATERIALS & INTERFACES 2023; 15:59087-59098. [PMID: 38078441 PMCID: PMC10739585 DOI: 10.1021/acsami.3c14794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/22/2023]
Abstract
Nonionic surfactants used in agri-spraying processes may cause varying degrees of corneal irritation when they come in direct contact with farmers' eyes, and the exact irritations are thought to be determined by how surfactants interact with corneal cell membranes. However, how nonionic surfactants interact with cell membranes at the molecular and nano levels remains largely unexplored. In this study, the interactions between nonionic surfactants (alkyl ethoxylate, C12Em) and lipid membranes were examined by membrane permeability measurement, quartz crystal microbalance with dissipation, dual polarization interferometry, confocal laser scanning microscopy, and neutron reflection, aiming to reveal complementary structural features at the molecular and nano levels. Apart from the extremely hydrophobic surfactant C12E2, all nonionic surfactants studied could penetrate the model cell membrane composed of a phosphocholine lipid bilayer. Nonionic surfactants with intermediate amphiphilicity (C12E6) rapidly fused into the lipid membrane and stimulated the formation of pores across the lipid bilayer, consistent with the cytoplasm leakage and fast cell necrosis observed from the cytotoxicity study of corneal cells. In comparison, while hydrophobic and hydrophilic surfactants [those with long and short ethoxylates (C12E4,12,23)] could cause mild structural alteration to the outer lipid layer of the membrane, these structural changes were insufficient to elicit large cytoplasmic leakage rapidly and instead cell death occurred over longer periods of time due to changes in the membrane permeability. These results reveal the strong link of surfactant-lipid membrane interactions to surfactant cytotoxicity and the association with amphiphilicity of nonionic surfactants.
Collapse
Affiliation(s)
- Xuzhi Hu
- Biological
Physics Group, Department of Physics and Astronomy, School of Natural
Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Mingrui Liao
- Biological
Physics Group, Department of Physics and Astronomy, School of Natural
Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Kangcheng Shen
- Biological
Physics Group, Department of Physics and Astronomy, School of Natural
Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Ke Ding
- Biological
Physics Group, Department of Physics and Astronomy, School of Natural
Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| | - Mario Campana
- Rutherford
Appleton Laboratory, STFC ISIS Facility, Didcot OX11 0QX, U.K.
| | - Sophie van der Kamp
- Jealott’s
Hill International Research Centre, Syngenta, Bracknell, Berkshire RG42
6EY, U.K.
| | - Elizabeth F. McInnes
- Jealott’s
Hill International Research Centre, Syngenta, Bracknell, Berkshire RG42
6EY, U.K.
| | - Faheem Padia
- Jealott’s
Hill International Research Centre, Syngenta, Bracknell, Berkshire RG42
6EY, U.K.
| | - Jian R. Lu
- Biological
Physics Group, Department of Physics and Astronomy, School of Natural
Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
| |
Collapse
|
2
|
Lee TH, Hofferek V, Sani MA, Separovic F, Reid GE, Aguilar MI. The impact of antibacterial peptides on bacterial lipid membranes depends on stage of growth. Faraday Discuss 2021; 232:399-418. [DOI: 10.1039/d0fd00052c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Impact of maculatin 1.1 on supported lipid bilayers (SLBs) derived from early growth phase (EGP) or stationary growth phase (SGP) E. coli lipid extracts, monitored by atomic force microscopy which images bilayer morphology in real time.
Collapse
Affiliation(s)
- Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Vinzenz Hofferek
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
| | - Marc-Antoine Sani
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
| | - Gavin E. Reid
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| |
Collapse
|
3
|
Nielsen JE, Prévost SF, Jenssen H, Lund R. Impact of antimicrobial peptides on E. coli-mimicking lipid model membranes: correlating structural and dynamic effects using scattering methods. Faraday Discuss 2021; 232:203-217. [DOI: 10.1039/d0fd00046a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using X-rays and neutrons we address the effect of AMPs on structure and dynamics of lipids in bacterial model membranes.
Collapse
Affiliation(s)
| | | | - Håvard Jenssen
- Department of Science and Environment, Roskilde University, 4000 Roskilde, Denmark
| | - Reidar Lund
- Department of Chemistry, University of Oslo, 0315 Oslo, Norway
| |
Collapse
|
4
|
Nielsen JE, König N, Yang S, Skoda MWA, Maestro A, Dong H, Cárdenas M, Lund R. Lipid membrane interactions of self-assembling antimicrobial nanofibers: effect of PEGylation. RSC Adv 2020; 10:35329-35340. [PMID: 35515685 PMCID: PMC9056946 DOI: 10.1039/d0ra07679a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/11/2020] [Indexed: 12/18/2022] Open
Abstract
Supramolecular assembly and PEGylation (attachment of a polyethylene glycol polymer chain) of peptides can be an effective strategy to develop antimicrobial peptides with increased stability, antimicrobial efficacy and hemocompatibility. However, how the self-assembly properties and PEGylation affect their lipid membrane interaction is still an unanswered question. In this work, we use state-of-the-art small angle X-ray and neutron scattering (SAXS/SANS) together with neutron reflectometry (NR) to study the membrane interaction of a series of multidomain peptides, with and without PEGylation, known to self-assemble into nanofibers. Our approach allows us to study both how the structure of the peptide and the membrane are affected by the peptide-lipid interactions. When comparing self-assembled peptides with monomeric peptides that are not able to undergo assembly due to shorter chain length, we found that the nanofibers interact more strongly with the membrane. They were found to insert into the core of the membrane as well as to absorb as intact fibres on the surface. Based on the presented results, PEGylation of the multidomain peptides leads to a slight net decrease in the membrane interaction, while the distribution of the peptide at the interface is similar to the non-PEGylated peptides. Based on the structural information, we showed that nanofibers were partially disrupted upon interaction with phospholipid membranes. This is in contrast with the considerable physical stability of the peptide in solution, which is desirable for an extended in vivo circulation time.
Collapse
Affiliation(s)
| | - Nico König
- Department of Chemistry, University of Oslo 0315 Oslo Norway .,Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH 52425 Jülich Germany
| | - Su Yang
- Department of Chemistry & Biochemistry, The University of Texas at Arlington Arlington Texas 76019 USA
| | - Maximilian W A Skoda
- ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory Harwell Science and Innovation Campus, Didco Oxfordshire OX11 OQX UK
| | | | - He Dong
- Department of Chemistry & Biochemistry, The University of Texas at Arlington Arlington Texas 76019 USA
| | - Marité Cárdenas
- Biofilms Research Center for Biointerfaces, Department of Biomedical Science, Health and Society, Malmö University 20506 Malmö Sweden
| | - Reidar Lund
- Department of Chemistry, University of Oslo 0315 Oslo Norway
| |
Collapse
|
5
|
Le Brun AP, Zhu S, Sani MA, Separovic F. The Location of the Antimicrobial Peptide Maculatin 1.1 in Model Bacterial Membranes. Front Chem 2020; 8:572. [PMID: 32733854 PMCID: PMC7358649 DOI: 10.3389/fchem.2020.00572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022] Open
Abstract
Maculatin 1.1 (Mac1) is an antimicrobial peptide (AMP) from the skin secretions of Australian tree frogs. In this work, the interaction of Mac1 with anionic phospholipid bilayers was investigated by NMR, circular dichroism (CD) spectroscopy, neutron reflectometry (NR) and molecular dynamics (MD). In buffer, the peptide is unstructured but in the presence of anionic (DPC/LMPG) micelles or (DMPC/DMPG/DHPC) bicelles adopts a helical structure. Addition of the soluble paramagnetic agent gadolinium (Gd-DTPA) into the Mac1-DPC/LMPG micelle solution showed that the N-terminus is more exposed to the hydrophilic Gd-DTPA than the C-terminus in micelles. 2H and 31P solid-state NMR showed that Mac1 had a greater effect on the anionic lipid (DMPG). A deuterium labeled Mac1 used in NR experiments indicated that the AMP spanned across anionic (PC/PG) bilayers, which was compatible with MD simulations. Simulations also showed that Mac1 orientation remained transmembrane in bilayers and wrapped on the surface of the micelles regardless of the lipid or detergent charge. Thus, the peptide orientation appears to be more susceptible to curvature than charged surface. These results support the formation of transmembrane pores by Mac1 in model bacterial membranes.
Collapse
Affiliation(s)
- Anton P Le Brun
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Shiying Zhu
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Marc-Antoine Sani
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
6
|
Sani MA, Le Brun AP, Separovic F. The antimicrobial peptide maculatin self assembles in parallel to form a pore in phospholipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183204. [DOI: 10.1016/j.bbamem.2020.183204] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/15/2019] [Accepted: 01/21/2020] [Indexed: 01/06/2023]
|
7
|
Membrane interactions of antimicrobial peptide-loaded microgels. J Colloid Interface Sci 2020; 562:322-332. [DOI: 10.1016/j.jcis.2019.12.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/16/2022]
|
8
|
Galván-Hernández A, Kobayashi N, Hernández-Cobos J, Antillón A, Nakabayashi S, Ortega-Blake I. Morphology and dynamics of domains in ergosterol or cholesterol containing membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183101. [DOI: 10.1016/j.bbamem.2019.183101] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 10/02/2019] [Accepted: 10/24/2019] [Indexed: 12/19/2022]
|
9
|
Aghebati T, Arabsalmani M, Mohammadpour AH, Afshar M, Jaafari MR, Abnous K, Nazemi S, Badiee A. Development of an effective liposomal cholesterol ester transfer protein (CETP) vaccine for protecting against atherosclerosis in rabbit model. Pharm Dev Technol 2019; 25:432-439. [PMID: 31852350 DOI: 10.1080/10837450.2019.1706181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Clinical trials of cholesterol ester transfer protein (CETP) peptide vaccine were stopped after disappointing results in humans due to the inadequacy of adjuvant aluminum hydroxide in stimulating the immune response against the self-antigen of CETP. To increase the efficacy of the CETP vaccine, we developed a novel liposomal form of tetanus toxoid-CETP (TT-CETP) peptide (Lip CETP) with well-characterized properties and high encapsulation efficiency. The vaccine efficacy against atherosclerosis was evaluated in rabbits challenged with a high cholesterol diet. Rabbits were immunized with Lip-CETP or liposome containing CETP with CpG ODN (Lip CETP/CpG). Control groups received empty liposomes or buffer. Anti-TT-CETP specific antibodies in serum were determined and gene expression of cytokine IFN-γ and IL-4 were measured in blood peripheral mononuclear cells. Therapeutic response was evaluated by titration of plasma lipoproteins during the study and pathologic analysis of aorta atherosclerotic lesions at the end. Lip-CETP/CpG elicited strong anti-TT-CETP antibodies and a higher IFN-γ level than the buffer. IL-4 was lower than the buffer in all vaccinated groups. Plasma lipoproteins showed no significant difference in the studied groups. Atherosclerosis thickness grade of the aorta was lower than the buffer group (p < 0.001) in rabbits vaccinated with Lip-CETP but not with Lip-CETP/CpG. In conclusion, Lip-CETP showed a strong atheroprotective effect.
Collapse
Affiliation(s)
- Tamara Aghebati
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahdieh Arabsalmani
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amir Hooshang Mohammadpour
- Department of Pharmacodynamy and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Afshar
- Department of Anatomy, Faculty of Medicine, Birjand University of Medical Sciences, Birjand, Iran.,Medical Toxicology Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Reza Jaafari
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.,Biotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Khalil Abnous
- Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saeed Nazemi
- Department of Cardiovascular Diseases, Razavi Hospital, Mashhad, Iran
| | - Ali Badiee
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| |
Collapse
|
10
|
A biophysical study of the interactions between the antimicrobial peptide indolicidin and lipid model systems. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:1355-1364. [DOI: 10.1016/j.bbamem.2019.04.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/22/2019] [Accepted: 04/07/2019] [Indexed: 12/19/2022]
|
11
|
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
|
12
|
Mumtaz Virk M, Hofmann B, Reimhult E. Formation and Characteristics of Lipid-Blended Block Copolymer Bilayers on a Solid Support Investigated by Quartz Crystal Microbalance and Atomic Force Microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:739-749. [PMID: 30580525 DOI: 10.1021/acs.langmuir.8b03597] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Liposomes grafted with polymer have long been used in drug delivery applications, and block copolymersomes have emerged as attractive and more robust alternatives for both drug delivery and artificial organelle applications. Hybrid membranes that could combine the respective advantages of fluid lipid and robust polymer bilayers are an attractive and enticing alternative. The properties of membranes in amphiphile vesicles are challenging to study and many applications benefit from surface-based access to the membrane. We therefore explore the self-assembly and mechanical properties of supported hybrid bilayers (SHBs) composed of polybutadiene- block-poly(ethylene oxide) block copolymers and zwitterionic phosphatidylcholine lipids on SiO2 supports. Quartz crystal microbalance with dissipation monitoring (QCM-D) measurements show that formation of SHB on SiO2 by vesicle fusion depends on the mass fractions of lipids and block copolymers. Atomic force microscopy was used to study the microscopic mixing of lipids in the SHB to reveal that lipid-phase separation is not observed in SHBs. Force spectroscopy was performed to extract information about thickness and mechanical properties of the hybrid membranes. SHBs are shown to combine the properties of lipid membranes and polymer brushes, and the tip force required to rupture the membrane decreases and the bilayer thickness increases as the block copolymer fraction is increased.
Collapse
Affiliation(s)
- Mudassar Mumtaz Virk
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences Vienna , Muthgasse 11 , 1190 Vienna , Austria
| | - Benedikt Hofmann
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences Vienna , Muthgasse 11 , 1190 Vienna , Austria
| | - Erik Reimhult
- Institute for Biologically Inspired Materials, Department of Nanobiotechnology , University of Natural Resources and Life Sciences Vienna , Muthgasse 11 , 1190 Vienna , Austria
| |
Collapse
|
13
|
Clifton LA, Hall SCL, Mahmoudi N, Knowles TJ, Heinrich F, Lakey JH. Structural Investigations of Protein-Lipid Complexes Using Neutron Scattering. Methods Mol Biol 2019; 2003:201-251. [PMID: 31218621 DOI: 10.1007/978-1-4939-9512-7_11] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Neutron scattering has significant benefits for examining the structure of protein-lipid complexes. Cold (slow) neutrons are nondamaging and predominantly interact with the atomic nucleus, meaning that neutron beams can penetrate deeply into samples, which allows for flexibility in the design of samples studied. Most importantly, there is a strong difference in neutron scattering length (i.e., scattering power) between protium ([Formula: see text], 99.98% natural abundance) and deuterium ([Formula: see text] or D, 0.015%). Through the mixing of H2O and D2O in the samples and in some cases the deuterium labeling of the biomolecules, components within a complex can be hidden or enhanced in the scattering signal. This enables both the overall structure and the relative distribution of components within a complex to be resolved. Lipid-protein complexes are most commonly studied using neutron reflectometry (NR) and small angle neutron scattering (SANS). In this review the methodologies to produce and examine a variety of model biological membrane systems using SANS and NR are detailed. These systems include supported lipid bilayers derived from vesicle dispersions or Langmuir-Blodgett deposition, tethered bilayer systems, membrane protein-lipid complexes and polymer wrapped lipid nanodiscs. The three key stages of any SANS/NR study on model membrane systems-sample preparation, data collection, and analysis-are described together with some background on the techniques themselves.
Collapse
Affiliation(s)
- Luke A Clifton
- Rutherford Appleton Laboratory, Science and Technology Facilities Council, Didcot, Oxfordshire, UK.
| | - Stephen C L Hall
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Najet Mahmoudi
- Rutherford Appleton Laboratory, Science and Technology Facilities Council, Didcot, Oxfordshire, UK
| | - Timothy J Knowles
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Frank Heinrich
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA
- National Institute of Standards and Technology Centre for Neutron Research, Gaithersburg, MD, USA
| | - Jeremy H Lakey
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne, UK.
| |
Collapse
|
14
|
Lee TH, Hirst DJ, Kulkarni K, Del Borgo MP, Aguilar MI. Exploring Molecular-Biomembrane Interactions with Surface Plasmon Resonance and Dual Polarization Interferometry Technology: Expanding the Spotlight onto Biomembrane Structure. Chem Rev 2018; 118:5392-5487. [PMID: 29793341 DOI: 10.1021/acs.chemrev.7b00729] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The molecular analysis of biomolecular-membrane interactions is central to understanding most cellular systems but has emerged as a complex technical challenge given the complexities of membrane structure and composition across all living cells. We present a review of the application of surface plasmon resonance and dual polarization interferometry-based biosensors to the study of biomembrane-based systems using both planar mono- or bilayers or liposomes. We first describe the optical principals and instrumentation of surface plasmon resonance, including both linear and extraordinary transmission modes and dual polarization interferometry. We then describe the wide range of model membrane systems that have been developed for deposition on the chips surfaces that include planar, polymer cushioned, tethered bilayers, and liposomes. This is followed by a description of the different chemical immobilization or physisorption techniques. The application of this broad range of engineered membrane surfaces to biomolecular-membrane interactions is then overviewed and how the information obtained using these techniques enhance our molecular understanding of membrane-mediated peptide and protein function. We first discuss experiments where SPR alone has been used to characterize membrane binding and describe how these studies yielded novel insight into the molecular events associated with membrane interactions and how they provided a significant impetus to more recent studies that focus on coincident membrane structure changes during binding of peptides and proteins. We then discuss the emerging limitations of not monitoring the effects on membrane structure and how SPR data can be combined with DPI to provide significant new information on how a membrane responds to the binding of peptides and proteins.
Collapse
Affiliation(s)
- Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology and Biomedicine Discovery Institute , Monash University , Clayton , VIC 3800 , Australia
| | - Daniel J Hirst
- Department of Biochemistry and Molecular Biology and Biomedicine Discovery Institute , Monash University , Clayton , VIC 3800 , Australia
| | - Ketav Kulkarni
- Department of Biochemistry and Molecular Biology and Biomedicine Discovery Institute , Monash University , Clayton , VIC 3800 , Australia
| | - Mark P Del Borgo
- Department of Biochemistry and Molecular Biology and Biomedicine Discovery Institute , Monash University , Clayton , VIC 3800 , Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology and Biomedicine Discovery Institute , Monash University , Clayton , VIC 3800 , Australia
| |
Collapse
|
15
|
Hedegaard SF, Derbas MS, Lind TK, Kasimova MR, Christensen MV, Michaelsen MH, Campbell RA, Jorgensen L, Franzyk H, Cárdenas M, Nielsen HM. Fluorophore labeling of a cell-penetrating peptide significantly alters the mode and degree of biomembrane interaction. Sci Rep 2018; 8:6327. [PMID: 29679078 PMCID: PMC5910404 DOI: 10.1038/s41598-018-24154-z] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 03/28/2018] [Indexed: 12/05/2022] Open
Abstract
The demand for highly efficient macromolecular drugs, used in the treatment of many severe diseases, is continuously increasing. However, the hydrophilic character and large molecular size of these drugs significantly limit their ability to permeate across cellular membranes and thus impede the drugs in reaching their target sites in the body. Cell-penetrating peptides (CPP) have gained attention as promising drug excipients, since they can facilitate drug permeation across cell membranes constituting a major biological barrier. Fluorophores are frequently covalently conjugated to CPPs to improve detection, however, the ensuing change in physico-chemical properties of the CPPs may alter their biological properties. With complementary biophysical techniques, we show that the mode of biomembrane interaction may change considerably upon labeling of the CPP penetratin (PEN) with a fluorophore. Fluorophore-PEN conjugates display altered modes of membrane interaction with increased insertion into the core of model cell membranes thereby exerting membrane-thinning effects. This is in contrast to PEN, which localizes along the head groups of the lipid bilayer, without affecting the thickness of the lipid tails. Particularly high membrane disturbance is observed for the two most hydrophobic PEN conjugates; rhodamine B or 1-pyrene butyric acid, as compared to the four other tested fluorophore-PEN conjugates.
Collapse
Affiliation(s)
- Sofie Fogh Hedegaard
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - Mohammed Sobhi Derbas
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - Tania Kjellerup Lind
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Faculty of Health and Society, Malmö University, Per Albin Hanssons väg 35, 214 32, Malmö, Sweden
| | - Marina Robertnova Kasimova
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.,Symphogen A/S, Pederstrupvej 93, 2750, Ballerup, Denmark
| | - Malene Vinther Christensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 162, 2100, Copenhagen, Denmark
| | - Maria Høtoft Michaelsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - Richard A Campbell
- Institut Laue-Langevin, 71 avenue des Martyrs, CS20156, 38042, Grenoble, France
| | - Lene Jorgensen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - Henrik Franzyk
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 162, 2100, Copenhagen, Denmark
| | - Marité Cárdenas
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Faculty of Health and Society, Malmö University, Per Albin Hanssons väg 35, 214 32, Malmö, Sweden.
| | - Hanne Mørck Nielsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.
| |
Collapse
|
16
|
Lee TH, Sani MA, Overall S, Separovic F, Aguilar MI. Effect of phosphatidylcholine bilayer thickness and molecular order on the binding of the antimicrobial peptide maculatin 1.1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:300-309. [DOI: 10.1016/j.bbamem.2017.10.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 09/18/2017] [Accepted: 10/08/2017] [Indexed: 01/01/2023]
|
17
|
Ciumac D, Campbell RA, Clifton LA, Xu H, Fragneto G, Lu JR. Influence of Acyl Chain Saturation on the Membrane-Binding Activity of a Short Antimicrobial Peptide. ACS OMEGA 2017; 2:7482-7492. [PMID: 30023555 PMCID: PMC6044940 DOI: 10.1021/acsomega.7b01270] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 10/12/2017] [Indexed: 05/03/2023]
Abstract
Different bacterial types and their living environments can lead to different saturations in the chains of their membrane lipids. Such structural differences may influence the efficacy of antibiotics that target bacterial membranes. In this work, the effects of acyl chain saturation on the binding of an antimicrobial peptide G4 have been examined as a function of the packing density of lipid monolayers by combining external reflection Fourier transform infrared (ER-FTIR) spectroscopy and neutron reflection (NR) measurements. Langmuir monolayers were formed from 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DPPG) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG), respectively, with the initial surface pressures controlled at 8 and 28 mN/m. A reduction in the order of the acyl chains associated with the increase in the layer thickness upon G4 binding was revealed from ER-FTIR spectroscopy, with peptide binding reaching equilibration faster in POPG than in DPPG monolayers. Whereas the dynamic DPPG-binding process displayed a steady increase in the amide I band area, the POPG-binding process showed little change in the amide area after the initial period. The peptide amide I area from ER-FTIR spectroscopy could be linearly correlated with the adsorbed G4 amount from NR, irrespective of time, initial pressure, or chain saturation, with clearly more peptide incorporated into the DPPG monolayer. Furthermore, NR revealed that although the peptide was associated with both POPG and DPPG lipid monolayers, it was more extensively distributed in the latter, showing that acyl chain saturation clearly promoted peptide binding and structural disruption.
Collapse
Affiliation(s)
- Daniela Ciumac
- Biological
Physics Laboratory, School of Physics and Astronomy, University of Manchester, Oxford Road, Schuster Building, Manchester M13 9PL, U.K.
| | - Richard A. Campbell
- Institute
of Laue Langevin, 71
Avenue des Martyrs, CS-20156, 38042 Grenoble, France
| | | | - Hai Xu
- Centre
for Bioengineering and Biotechnology, China
University of Petroleum, Qingdao 266580, China
| | - Giovanna Fragneto
- Institute
of Laue Langevin, 71
Avenue des Martyrs, CS-20156, 38042 Grenoble, France
| | - Jian R. Lu
- Biological
Physics Laboratory, School of Physics and Astronomy, University of Manchester, Oxford Road, Schuster Building, Manchester M13 9PL, U.K.
- E-mail: . Phone: +44 161 2003926 (J.R.L.)
| |
Collapse
|
18
|
Sani MA, Carne S, Overall SA, Poulhazan A, Separovic F. One pathogen two stones: are Australian tree frog antimicrobial peptides synergistic against human pathogens? EUROPEAN BIOPHYSICS JOURNAL: EBJ 2017; 46:639-646. [PMID: 28478484 DOI: 10.1007/s00249-017-1215-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 02/28/2017] [Accepted: 04/24/2017] [Indexed: 01/10/2023]
Abstract
Antimicrobial peptides (AMPs) may act by targeting the lipid membranes and disrupting the bilayer structure. In this study, three AMPs from the skin of Australian tree frogs, aurein 1.2, maculatin 1.1 and caerin 1.1, were investigated against Gram-negative Escherichia coli, Gram-positive Staphylococcus aureus, and vesicles that mimic their lipid compositions. Furthermore, equimolar mixtures of the peptides were tested to identify any synergistic interactions in antimicrobial activity. Minimum inhibition concentration and minimum bactericidal concentration assays showed significant activity against S. aureus but not against E. coli. Aurein was the least active while maculatin was the most active peptide and some synergistic effects were observed against S. aureus. Circular dichroism experiments showed that, in the presence of phospholipid vesicles, the peptides transitioned from an unstructured to a predominantly helical conformation (>50%), with greater helicity for POPG/TOCL compared to POPE/POPG vesicles. The helical content, however, was less in the presence of live E. coli and S. aureus, 25 and 5%, respectively. Equimolar concentrations of the peptides did not appear to form greater supramolecular structures. Dye release assays showed that aurein required greater concentration than caerin and maculatin to disrupt the lipid bilayers, and mixtures of the peptides did not cooperate to enhance their lytic activity. Overall, aurein, maculatin, and caerin showed moderate synergy in antimicrobial activity against S. aureus without becoming more structured or enhancement of their membrane-disrupting activity in phospholipid vesicles.
Collapse
Affiliation(s)
- Marc-Antoine Sani
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, 3010, Australia.
| | - Siobhan Carne
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Sarah A Overall
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Alexandre Poulhazan
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, 3010, Australia
- Universite Pierre et Marie Curie (Paris VI), 4 Place Jussieu, 75252, Paris Cedex 5, France
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, 3010, Australia.
| |
Collapse
|
19
|
Narayanan T, Wacklin H, Konovalov O, Lund R. Recent applications of synchrotron radiation and neutrons in the study of soft matter. CRYSTALLOGR REV 2017. [DOI: 10.1080/0889311x.2016.1277212] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
| | - Hanna Wacklin
- European Spallation Source ERIC, Lund, Sweden
- Physical Chemistry, Lund University, Lund, Sweden
| | | | - Reidar Lund
- Department of Chemistry, University of Oslo, Blindern, Oslo, Norway
| |
Collapse
|
20
|
Graef F, Vukosavljevic B, Michel JP, Wirth M, Ries O, De Rossi C, Windbergs M, Rosilio V, Ducho C, Gordon S, Lehr CM. The bacterial cell envelope as delimiter of anti-infective bioavailability - An in vitro permeation model of the Gram-negative bacterial inner membrane. J Control Release 2016; 243:214-224. [PMID: 27769806 DOI: 10.1016/j.jconrel.2016.10.018] [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: 08/25/2016] [Revised: 10/11/2016] [Accepted: 10/15/2016] [Indexed: 11/26/2022]
Abstract
Gram-negative bacteria possess a unique and complex cell envelope, composed of an inner and outer membrane separated by an intermediate cell wall-containing periplasm. This tripartite structure acts intrinsically as a significant biological barrier, often limiting the permeation of anti-infectives, and so preventing such drugs from reaching their target. Furthermore, identification of the specific permeation-limiting envelope component proves difficult in the case of many anti-infectives, due to the challenges associated with isolation of individual cell envelope structures in bacterial culture. The development of an in vitro permeation model of the Gram-negative inner membrane, prepared by repeated coating of physiologically-relevant phospholipids on Transwell® filter inserts, is therefore reported, as a first step in the development of an overall cell envelope model. Characterization and permeability investigations of model compounds as well as anti-infectives confirmed the suitability of the model for quantitative and kinetically-resolved permeability assessment, and additionally confirmed the importance of employing bacteria-specific base materials for more accurate mimicking of the inner membrane lipid composition - both advantages compared to the majority of existing in vitro approaches. Additional incorporation of further elements of the Gram-negative bacterial cell envelope could ultimately facilitate model application as a screening tool in anti-infective drug discovery or formulation development.
Collapse
Affiliation(s)
- Florian Graef
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Department of Drug Delivery, Campus E8 1, 66123 Saarbrücken, Germany.
| | - Branko Vukosavljevic
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Department of Drug Delivery, Campus E8 1, 66123 Saarbrücken, Germany.
| | - Jean-Philippe Michel
- Institut Galien Paris Sud, UMR 8612, Univ Paris-Sud, CNRS, Université Paris-Saclay, 5 rue J.B. Clément, F-92290 Châtenay-Malabry, France.
| | - Marius Wirth
- Saarland University, Department of Pharmacy, Pharmaceutical and Medicinal Chemistry, Campus C2 3, 66123 Saarbrücken, Germany.
| | - Oliver Ries
- Saarland University, Department of Pharmacy, Pharmaceutical and Medicinal Chemistry, Campus C2 3, 66123 Saarbrücken, Germany
| | - Chiara De Rossi
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Department of Drug Delivery, Campus E8 1, 66123 Saarbrücken, Germany.
| | - Maike Windbergs
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Department of Drug Delivery, Campus E8 1, 66123 Saarbrücken, Germany.
| | - Véronique Rosilio
- Institut Galien Paris Sud, UMR 8612, Univ Paris-Sud, CNRS, Université Paris-Saclay, 5 rue J.B. Clément, F-92290 Châtenay-Malabry, France.
| | - Christian Ducho
- Saarland University, Department of Pharmacy, Pharmaceutical and Medicinal Chemistry, Campus C2 3, 66123 Saarbrücken, Germany.
| | - Sarah Gordon
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Department of Drug Delivery, Campus E8 1, 66123 Saarbrücken, Germany.
| | - Claus-Michael Lehr
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Department of Drug Delivery, Campus E8 1, 66123 Saarbrücken, Germany; Saarland University, Department of Pharmacy, Biopharmacy and Pharmaceutical Technology, Campus E8 1, 66123 Saarbrücken, Germany.
| |
Collapse
|
21
|
Yepuri NR, Darwish TA, Krause-Heuer AM, Leung AE, Delhom R, Wacklin HP, Holden PJ. Synthesis of Perdeuterated 1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine ([D 82 ]POPC) and Characterisation of Its Lipid Bilayer Membrane Structure by Neutron Reflectometry. Chempluschem 2016; 81:315-321. [PMID: 31968790 DOI: 10.1002/cplu.201500452] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Indexed: 11/05/2022]
Abstract
1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), an unsaturated acyl chain containing lipid, is often the predominant lipid in eukaryotic cell membranes in which it is crucial for the fluidity of membranes under physiological conditions. Commercially available, partially deuterated [D31 ]1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine ([D31 ]POPC) does not provide sufficient isotopic contrast for detailed structural studies of multicomponent membranes through neutron techniques. Herein, a relatively straightforward and generic chemical deuteration method is discussed for the asymmetric synthesis of perdeuterated [D31 ]1-palmitoyl-[D33 ]2-oleoyl-sn-[D5 ]glycero-[D13 ]3-phosphocholine ([D82 ]POPC) that also allows selective deuteration of any of its constituent groups. Neutron reflectivity of a [D82 ]POPC-supported bilayer was used to experimentally determine the neutron scattering length density profile of the lipid. The acyl chains of [D82 ]POPC are closely contrast-matched to heavy water, whereas the very high scattering length density of the deuterated glycerophosphocholine head groups provides good contrast to membrane-binding agents in both deuterated and non-deuterated solvent environments.
Collapse
Affiliation(s)
- Nageshwar R Yepuri
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW, 2232, Australia
| | - Tamim A Darwish
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW, 2232, Australia
| | - Anwen M Krause-Heuer
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW, 2232, Australia
| | - Anna E Leung
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW, 2232, Australia
| | - Robin Delhom
- European Spallation Source ERIC, Box 176, 22100, Lund, Sweden.,Institut Laue Langevin (ILL), 71 av des Martyrs, 38042, Grenoble, France
| | - Hanna P Wacklin
- European Spallation Source ERIC, Box 176, 22100, Lund, Sweden.,Division of Physical Chemistry, Department of Chemistry, Lund Universit, P.O. Box 124, 22100, Lund, Sweden
| | - Peter J Holden
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW, 2232, Australia
| |
Collapse
|
22
|
Barker RD, McKinley LE, Titmuss S. Neutron Reflectivity as a Tool for Physics-Based Studies of Model Bacterial Membranes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 915:261-82. [PMID: 27193548 DOI: 10.1007/978-3-319-32189-9_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The principles of neutron reflectivity and its application as a tool to provide structural information at the (sub-) molecular unit length scale from models for bacterial membranes are described. The model membranes can take the form of a monolayer for a single leaflet spread at the air/water interface, or bilayers of increasing complexity at the solid/liquid interface. Solid-supported bilayers constrain the bilayer to 2D but can be used to characterize interactions with antimicrobial peptides and benchmark high throughput lab-based techniques. Floating bilayers allow for membrane fluctuations, making the phase behaviour more representative of native membranes. Bilayers of varying levels of compositional accuracy can now be constructed, facilitating studies with aims that range from characterizing the fundamental physical interactions, through to the characterization of accurate mimetics for the inner and outer membranes of Gram-negative bacteria. Studies of the interactions of antimicrobial peptides with monolayer and bilayer models for the inner and outer membranes have revealed information about the molecular control of the outer membrane permeability, and the mode of interaction of antimicrobials with both inner and outer membranes.
Collapse
Affiliation(s)
- Robert D Barker
- Institut Laue-Langevin, 71 Avenue Des Martyrs, CS 20156, 38042, Grenoble Cedex 9, France.,School of Science and Engineering, University of Dundee, James Clerk Maxwell Building, The King's Buildings, Peter Guthrie Tait Road, Dundee, DD1 4HN, UK
| | - Laura E McKinley
- School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, The King's Buildings, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, Scotland
| | - Simon Titmuss
- School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, The King's Buildings, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, Scotland.
| |
Collapse
|
23
|
Graef F, Gordon S, Lehr CM. Anti-infectives in Drug Delivery-Overcoming the Gram-Negative Bacterial Cell Envelope. Curr Top Microbiol Immunol 2016; 398:475-496. [PMID: 26942419 DOI: 10.1007/82_2016_491] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Infectious diseases are becoming a major menace to the state of health worldwide, with difficulties in effective treatment especially of nosocomial infections caused by Gram-negative bacteria being increasingly reported. Inadequate permeation of anti-infectives into or across the Gram-negative bacterial cell envelope, due to its intrinsic barrier function as well as barrier enhancement mediated by resistance mechanisms, can be identified as one of the major reasons for insufficient therapeutic effects. Several in vitro, in silico, and in cellulo models are currently employed to increase the knowledge of anti-infective transport processes into or across the bacterial cell envelope; however, all such models exhibit drawbacks or have limitations with respect to the information they are able to provide. Thus, new approaches which allow for more comprehensive characterization of anti-infective permeation processes (and as such, would be usable as screening methods in early drug discovery and development) are desperately needed. Furthermore, delivery methods or technologies capable of enhancing anti-infective permeation into or across the bacterial cell envelope are required. In this respect, particle-based carrier systems have already been shown to provide the opportunity to overcome compound-related difficulties and allow for targeted delivery. In addition, formulations combining efflux pump inhibitors or antimicrobial peptides with anti-infectives show promise in the restoration of antibiotic activity in resistant bacterial strains. Despite considerable progress in this field however, the design of carriers to specifically enhance transport across the bacterial envelope or to target difficult-to-treat (e.g., intracellular) infections remains an urgently needed area of improvement. What follows is a summary and evaluation of the state of the art of both bacterial permeation models and advanced anti-infective formulation strategies, together with an outlook for future directions in these fields.
Collapse
Affiliation(s)
- Florian Graef
- Department of Drug Delivery, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Saarbrücken, Germany
| | - Sarah Gordon
- Department of Drug Delivery, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Saarbrücken, Germany
| | - Claus-Michael Lehr
- Department of Drug Delivery, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), Saarbrücken, Germany. .,Department of Pharmacy, Saarland University, Saarbrücken, Germany.
| |
Collapse
|
24
|
Sani MA, Lee TH, Aguilar MI, Separovic F. Proline-15 creates an amphipathic wedge in maculatin 1.1 peptides that drives lipid membrane disruption. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:2277-89. [DOI: 10.1016/j.bbamem.2015.06.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/05/2015] [Accepted: 06/11/2015] [Indexed: 11/28/2022]
|
25
|
Lee TH, Hirst DJ, Aguilar MI. New insights into the molecular mechanisms of biomembrane structural changes and interactions by optical biosensor technology. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1868-85. [PMID: 26009270 DOI: 10.1016/j.bbamem.2015.05.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 05/15/2015] [Accepted: 05/17/2015] [Indexed: 12/31/2022]
Abstract
Biomolecular-membrane interactions play a critical role in the regulation of many important biological processes such as protein trafficking, cellular signalling and ion channel formation. Peptide/protein-membrane interactions can also destabilise and damage the membrane which can lead to cell death. Characterisation of the molecular details of these binding-mediated membrane destabilisation processes is therefore central to understanding cellular events such as antimicrobial action, membrane-mediated amyloid aggregation, and apoptotic protein induced mitochondrial membrane permeabilisation. Optical biosensors have provided a unique approach to characterising membrane interactions allowing quantitation of binding events and new insight into the kinetic mechanism of these interactions. One of the most commonly used optical biosensor technologies is surface plasmon resonance (SPR) and there have been an increasing number of studies reporting the use of this technique for investigating biophysical analysis of membrane-mediated events. More recently, a number of new optical biosensors based on waveguide techniques have been developed, allowing membrane structure changes to be measured simultaneously with mass binding measurements. These techniques include dual polarisation interferometry (DPI), plasmon waveguide resonance spectroscopy (PWR) and optical waveguide light mode spectroscopy (OWLS). These techniques have expanded the application of optical biosensors to allow the analysis of membrane structure changes during peptide and protein binding. This review provides a theoretical and practical overview of the application of biosensor technology with a specific focus on DPI, PWR and OWLS to study biomembrane-mediated events and the mechanism of biomembrane disruption. This article is part of a Special Issue entitled: Lipid-protein interactions.
Collapse
Affiliation(s)
- Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Rd, Clayton, VIC 3800, Australia
| | - Daniel J Hirst
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Rd, Clayton, VIC 3800, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Rd, Clayton, VIC 3800, Australia.
| |
Collapse
|
26
|
Escorihuela J, González-Martínez MÁ, López-Paz JL, Puchades R, Maquieira Á, Gimenez-Romero D. Dual-Polarization Interferometry: A Novel Technique To Light up the Nanomolecular World. Chem Rev 2014; 115:265-94. [DOI: 10.1021/cr5002063] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jorge Escorihuela
- Department
of Chemistry, Institute of Molecular Recognition and Technological
Development, Universitat Politècnica de València, Camino
de Vera s/n, 46022 València, Spain
| | - Miguel Ángel González-Martínez
- Department
of Chemistry, Institute of Molecular Recognition and Technological
Development, Universitat Politècnica de València, Camino
de Vera s/n, 46022 València, Spain
| | - José Luis López-Paz
- Department
of Chemistry, Institute of Molecular Recognition and Technological
Development, Universitat Politècnica de València, Camino
de Vera s/n, 46022 València, Spain
| | - Rosa Puchades
- Department
of Chemistry, Institute of Molecular Recognition and Technological
Development, Universitat Politècnica de València, Camino
de Vera s/n, 46022 València, Spain
| | - Ángel Maquieira
- Department
of Chemistry, Institute of Molecular Recognition and Technological
Development, Universitat Politècnica de València, Camino
de Vera s/n, 46022 València, Spain
| | - David Gimenez-Romero
- Physical
Chemistry Department, Faculty of Chemistry, Universitat de València, Avenida Dr. Moliner 50, 46100 Burjassot, València, Spain
| |
Collapse
|
27
|
Stereoselective synthesis of perdeuterated phytanic acid, its phospholipid derivatives and their formation into lipid model membranes for neutron reflectivity studies. Chem Phys Lipids 2014; 183:22-33. [DOI: 10.1016/j.chemphyslip.2014.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 04/01/2014] [Accepted: 04/07/2014] [Indexed: 11/23/2022]
|
28
|
Lind TK, Cárdenas M, Wacklin HP. Formation of Supported Lipid Bilayers by Vesicle Fusion: Effect of Deposition Temperature. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7259-63. [PMID: 24932971 DOI: 10.1021/la500897x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Affiliation(s)
- Tania Kjellerup Lind
- Nano-Science
Center and Institute of Chemistry, Copenhagen University, Copenhagen, Denmark
- European Spallation
Source ESS AB, Lund, Sweden
| | - Marité Cárdenas
- Nano-Science
Center and Institute of Chemistry, Copenhagen University, Copenhagen, Denmark
- Malmoe University, Health & Society, 20506 Malmoe, Sweden
| | - Hanna Pauliina Wacklin
- Nano-Science
Center and Institute of Chemistry, Copenhagen University, Copenhagen, Denmark
- European Spallation
Source ESS AB, Lund, Sweden
| |
Collapse
|
29
|
Real-time measurement of membrane conformational states induced by antimicrobial peptides: balance between recovery and lysis. Sci Rep 2014; 4:5479. [PMID: 24969959 PMCID: PMC4073255 DOI: 10.1038/srep05479] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 06/09/2014] [Indexed: 11/30/2022] Open
Abstract
The disruption of membranes by antimicrobial peptides is a multi-state process involving significant structural changes in the phospholipid bilayer. However, direct measurement of these membrane structural changes is lacking. We used a combination of dual polarisation interferometry (DPI), surface plasmon resonance spectroscopy (SPR) and atomic force microscopy (AFM) to measure the real-time changes in membrane structure through the measurement of birefringence during the binding of magainin 2 (Mag2) and a highly potent analogue in which Ser8, Gly13 and Gly18 has been replaced with alanine (Mag-A). We show that the membrane bilayer undergoes a series of structural changes upon peptide binding before a critical threshold concentration is reached which triggers a significant membrane disturbance. We also propose a detailed model for antimicrobial peptide action as a function of the degree of bilayer disruption to provide an unprecedented in-depth understanding of the membrane lysis in terms of the interconversion of different membrane conformational states in which there is a balance between recovery and lysis.
Collapse
|
30
|
Wadhwani P, Strandberg E, van den Berg J, Mink C, Bürck J, Ciriello RA, Ulrich AS. Dynamical structure of the short multifunctional peptide BP100 in membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:940-9. [DOI: 10.1016/j.bbamem.2013.11.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 10/25/2013] [Accepted: 11/01/2013] [Indexed: 11/26/2022]
|
31
|
Comparison of reversible membrane destabilisation induced by antimicrobial peptides derived from Australian frogs. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2205-15. [PMID: 24593995 DOI: 10.1016/j.bbamem.2014.02.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/21/2014] [Accepted: 02/21/2014] [Indexed: 12/28/2022]
Abstract
The membrane destabilising properties of the antimicrobial peptides (AMP) aurein 1.2, citropin 1.1, maculatin 1.1 and caerin 1.1, have been studied by dual polarisation interferometry (DPI). The overall process of peptide induced membrane destabilisation was examined by the changes in bilayer order as a function of membrane-bound peptide mass per unit area and revealed three different modes of action. Aurein 1.2 was the only peptide that significantly destabilised the neutral membrane (DMPC), while all four peptides induced destabilisation of the negatively charged membrane (DMPC/DMPG). On DMPC, citropin 1.1, maculatin 1.1 and caerin 1.1 bound irreversibly at low concentrations but caused a reversible drop in the bilayer order. In contrast to DMPC/DMPG, these three peptides caused a mass drop at the higher concentrations, which may correspond to insertion and bilayer expansion. The critical level of bound peptide necessary to induce membrane destabilisation (peptide:lipid ratio) was determined and correlated with peptide structure. As the most lytic peptide, aurein 1.2 adsorbed strongly prior to dissolution of the bilayer. In contrast, the binding of citropin 1.1, maculatin 1.1 and caerin 1.1 needed to reach a critical level prior to insertion into the membrane and incremental expansion and disruption. Our results demonstrate that sequential events can be monitored in real-time under fluidic conditions to elucidate the complex molecular mechanism of AMP action. In particular, the analysis of birefringence in real time allows the description of a detailed mechanistic model of the impact of peptides on the membrane bilayer order. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
Collapse
|
32
|
Balhara V, Deshmukh SS, Kálmán L, Kornblatt JA. The interaction of streptococcal enolase with canine plasminogen: the role of surfaces in complex formation. PLoS One 2014; 9:e88395. [PMID: 24520380 PMCID: PMC3919783 DOI: 10.1371/journal.pone.0088395] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 01/05/2014] [Indexed: 11/18/2022] Open
Abstract
The enolase from Streptococcus pyogenes (Str enolase F137L/E363G) is a homo-octamer shaped like a donut. Plasminogen (Pgn) is a monomeric protein composed of seven discrete separated domains organized into a lock washer. The enolase is known to bind Pgn. In past work we searched for conditions in which the two proteins would bind to one another. The two native proteins in solution would not bind under any of the tried conditions. We found that if the structures were perturbed binding would occur. We stated that only the non-native Str enolase or Pgn would interact such that we could detect binding. We report here the results of a series of dual polarization interferometry (DPI) experiments coupled with atomic force microscopy (AFM), isothermal titration calorimetry (ITC), dynamic light scattering (DLS), and fluorescence. We show that the critical condition for forming stable complexes of the two native proteins involves Str enolase binding to a surface. Surfaces that attract Str enolase are a sufficient condition for binding Pgn. Under certain conditions, Pgn adsorbed to a surface will bind Str enolase.
Collapse
Affiliation(s)
- Vinod Balhara
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Quebec, Canada
| | | | - László Kálmán
- Department of Physics, Concordia University, Montréal, Quebec, Canada
| | - Jack A. Kornblatt
- Department of Biology and the Centre for Structural and Functional Genomics, Concordia University, Montréal, Quebec, Canada
- * E-mail:
| |
Collapse
|
33
|
Balhara V, Schmidt R, Gorr SU, DeWolf C. Membrane selectivity and biophysical studies of the antimicrobial peptide GL13K. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2193-203. [DOI: 10.1016/j.bbamem.2013.05.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 05/24/2013] [Accepted: 05/27/2013] [Indexed: 01/27/2023]
|
34
|
Darwish TA, Luks E, Moraes G, Yepuri NR, Holden PJ, James M. Synthesis of deuterated [D32 ]oleic acid and its phospholipid derivative [D64 ]dioleoyl-sn-glycero-3-phosphocholine. J Labelled Comp Radiopharm 2013; 56:520-9. [PMID: 24285531 DOI: 10.1002/jlcr.3088] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 06/12/2013] [Accepted: 06/12/2013] [Indexed: 11/07/2022]
Abstract
Oleic acid and its phospholipid derivatives are fundamental to the structure and function of cellular membranes. As a result, there has been increasing interest in the availability of their deuterated forms for many nuclear magnetic resonance, infrared, mass spectroscopy and neutron scattering studies. Here, we present for the first time a straightforward, large-scale (gram quantities) synthesis of highly deuterated [D32 ]oleic acid by using multiple, yet simple and high yielding reactions. The precursors for the synthesis of [D32 ]oleic acid are [D14 ]azelaic acid and [D17 ]nonanoic acid, which were obtained by complete deuteration (>98% D) of their (1) H forms by using metal catalysed hydrothermal H/D exchange reactions. The oleic acid was produced with ca. 94% D isotopic purity and with no contamination by the trans-isomer (elaidic acid). The subsequent synthesis of [D64 ]dioleoyl-sn-glycero-3-phosphocholine from [D32 ]oleic acid is also described.
Collapse
Affiliation(s)
- Tamim A Darwish
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001 Kirrawee, DC NSW, 2232, Australia
| | | | | | | | | | | |
Collapse
|
35
|
Le Brun A, Clifton LA, Halbert CE, Lin B, Meron M, Holden PJ, Lakey JH, Holt SA. Structural characterization of a model gram-negative bacterial surface using lipopolysaccharides from rough strains of Escherichia coli. Biomacromolecules 2013; 14:2014-22. [PMID: 23617615 PMCID: PMC3679557 DOI: 10.1021/bm400356m] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 04/18/2013] [Indexed: 12/29/2022]
Abstract
Lipopolysaccharides (LPS) make up approximately 75% of the Gram-negative bacterial outer membrane (OM) surface, but because of the complexity of the molecule, there are very few model OMs that include LPS. The LPS molecule consists of lipid A, which anchors the LPS within the OM, a core polysaccharide region, and a variable O-antigen polysaccharide chain. In this work we used RcLPS (consisting of lipid A plus the first seven sugars of the core polysaccharide) from a rough strain of Escherichia coli to form stable monolayers of LPS at the air-liquid interface. The vertical structure RcLPS monolayers were characterized using neutron and X-ray reflectometry, while the lateral structure was investigated using grazing incidence X-ray diffraction and Brewster angle microscopy. It was found that RcLPS monolayers at surface pressures of 20 mN m(-1) and above are resolved as hydrocarbon tails, an inner headgroup, and an outer headgroup of polysaccharide with increasing solvation from tails to outer headgroups. The lateral organization of the hydrocarbon lipid chains displays an oblique hexagonal unit cell at all surface pressures, with only the chain tilt angle changing with surface pressure. This is in contrast to lipid A, which displays hexagonal or, above 20 mN m(-1), distorted hexagonal packing. This work provides the first complete structural analysis of a realistic E. coli OM surface model.
Collapse
Affiliation(s)
- Anton
P. Le Brun
- Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Luke A. Clifton
- ISIS Neutron Facility, STFC Rutherford
Appleton Laboratory, Didcot, Oxfordshire
OX11 0QX, United Kingdom
| | - Candice E. Halbert
- Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee
37831, United States
| | - Binhua Lin
- Consortium
of Advanced Radiation
Sources (CARS), University of Chicago,
Chicago, Illinois 60637, United States
| | - Mati Meron
- Consortium
of Advanced Radiation
Sources (CARS), University of Chicago,
Chicago, Illinois 60637, United States
| | - Peter J. Holden
- Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| | - Jeremy H. Lakey
- Institute for Cell and Molecular
Biosciences, Newcastle University, Framlington
Place, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Stephen A. Holt
- Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
| |
Collapse
|
36
|
Singh S, Kalle M, Papareddy P, Schmidtchen A, Malmsten M. Lipopolysaccharide Interactions of C-Terminal Peptides from Human Thrombin. Biomacromolecules 2013; 14:1482-92. [DOI: 10.1021/bm400150c] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Shalini Singh
- Department of Pharmacy, Uppsala University, SE-75123, Uppsala,
Sweden
| | - Martina Kalle
- Division of Dermatology
and
Venereology, Department of Clinical Sciences, Lund University, SE-221 84 Lund, Sweden
| | - Praveen Papareddy
- Division of Dermatology
and
Venereology, Department of Clinical Sciences, Lund University, SE-221 84 Lund, Sweden
| | - Artur Schmidtchen
- Division of Dermatology
and
Venereology, Department of Clinical Sciences, Lund University, SE-221 84 Lund, Sweden
| | - Martin Malmsten
- Department of Pharmacy, Uppsala University, SE-75123, Uppsala,
Sweden
| |
Collapse
|
37
|
Fernandez D, Lee TH, Sani MA, Aguilar MI, Separovic F. Proline facilitates membrane insertion of the antimicrobial peptide maculatin 1.1 via surface indentation and subsequent lipid disordering. Biophys J 2013; 104:1495-507. [PMID: 23561526 PMCID: PMC3617439 DOI: 10.1016/j.bpj.2013.01.059] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 01/23/2013] [Accepted: 01/28/2013] [Indexed: 01/08/2023] Open
Abstract
The role of proline in the disruption of membrane bilayer structure upon antimicrobial peptide (AMP) binding was studied. Specifically, (31)P and (2)H solid-state NMR and dual polarization interferometry (DPI) were used to analyze the membrane interactions of three AMPs: maculatin 1.1 and two analogs in which Pro-15 is replaced by Gly and Ala. For NMR, deuterated dimyristoylphosphatidylcholine (d54-DMPC) and d54-DMPC/dimyristoylphosphatidylglycerol (DMPG) were used to mimic eukaryotic and prokaryotic membranes, respectively. In fluid-phase DMPC bilayer systems, the peptides interacted primarily with the bilayer surface, with the native peptide having the strongest interaction. In the mixed DMPC/DMPG bilayers, maculatin 1.1 induced DMPG phase separation, whereas the analogs promoted the formation of isotropic and lipid-enriched phases with an enhanced effect relative to the neutral DMPC bilayers. In gel-phase DMPC vesicles, the native peptide disrupted the bilayer via a surface mechanism, and the effect of the analogs was similar to that observed in the fluid phase. Real-time changes in bilayer order were examined via DPI, with changes in bilayer birefringence analyzed as a function of the peptide mass bound to the bilayer. Although all three peptides decreased the bilayer order as a function of bound concentration, maculatin 1.1 caused the largest change in bilayer structure. The NMR data indicate that maculatin 1.1 binds predominantly at the surface regions of the bilayer, and both NMR and DPI results indicate that this binding leads to a drop in bilayer order. Overall, the results demonstrate that the proline at residue 15 plays a central role in the membrane interaction of maculatin 1.1 by inducing a significant change in membrane order and affecting the ability of the bilayer to recover from structural changes induced by the binding and insertion of the peptide.
Collapse
Affiliation(s)
- David I. Fernandez
- School of Chemistry, Bio21 Institute, University of Melbourne, Victoria, Australia
| | - Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Marc-Antoine Sani
- School of Chemistry, Bio21 Institute, University of Melbourne, Victoria, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, University of Melbourne, Victoria, Australia
| |
Collapse
|
38
|
Fernandez DI, Le Brun AP, Whitwell TC, Sani MA, James M, Separovic F. The antimicrobial peptide aurein 1.2 disrupts model membranes via the carpet mechanism. Phys Chem Chem Phys 2012; 14:15739-51. [PMID: 23093307 DOI: 10.1039/c2cp43099a] [Citation(s) in RCA: 134] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The membrane interactions of the antimicrobial peptide aurein 1.2 were studied using a range of biophysical techniques to determine the location and the mechanism of action in DMPC (dimyristoylphosphatidylcholine) and DMPC/DMPG (dimyristoylphosphatidylglycerol) model membranes that mimic characteristics of eukaryotic and prokaryotic membranes, respectively. Neutron reflectometry and solid-state NMR revealed subtle changes in membrane structure caused by the peptide. Quartz crystal microbalance with dissipation, vesicle dye leakage and atomic force microscopy measurements were used to investigate the global mode of peptide interaction. Aurein 1.2 displayed an enhanced interaction with the anionic DMPC/DMPG membrane while exhibiting primarily a surface interaction with both types of model membranes, which led to bilayer disruption and membrane lysis. The antimicrobial peptide interaction is consistent with the carpet mechanism for aurein 1.2 with discrete structural changes depending on the type of phospholipid membrane.
Collapse
Affiliation(s)
- David I Fernandez
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia
| | | | | | | | | | | |
Collapse
|