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Guryanova SV, Balandin SV, Belogurova-Ovchinnikova OY, Ovchinnikova TV. Marine Invertebrate Antimicrobial Peptides and Their Potential as Novel Peptide Antibiotics. Mar Drugs 2023; 21:503. [PMID: 37888438 PMCID: PMC10608444 DOI: 10.3390/md21100503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/14/2023] [Accepted: 09/21/2023] [Indexed: 10/28/2023] Open
Abstract
Marine invertebrates constantly interact with a wide range of microorganisms in their aquatic environment and possess an effective defense system that has enabled their existence for millions of years. Their lack of acquired immunity sets marine invertebrates apart from other marine animals. Invertebrates could rely on their innate immunity, providing the first line of defense, survival, and thriving. The innate immune system of marine invertebrates includes various biologically active compounds, and specifically, antimicrobial peptides. Nowadays, there is a revive of interest in these peptides due to the urgent need to discover novel drugs against antibiotic-resistant bacterial strains, a pressing global concern in modern healthcare. Modern technologies offer extensive possibilities for the development of innovative drugs based on these compounds, which can act against bacteria, fungi, protozoa, and viruses. This review focuses on structural peculiarities, biological functions, gene expression, biosynthesis, mechanisms of antimicrobial action, regulatory activities, and prospects for the therapeutic use of antimicrobial peptides derived from marine invertebrates.
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Affiliation(s)
- Svetlana V. Guryanova
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.V.G.); (S.V.B.)
- Medical Institute, Peoples’ Friendship University of Russia, 117198 Moscow, Russia
| | - Sergey V. Balandin
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.V.G.); (S.V.B.)
| | | | - Tatiana V. Ovchinnikova
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.V.G.); (S.V.B.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia;
- Department of Biotechnology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
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2
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Gong H, Hu X, Zhang L, Fa K, Liao M, Liu H, Fragneto G, Campana M, Lu JR. How do antimicrobial peptides disrupt the lipopolysaccharide membrane leaflet of Gram-negative bacteria? J Colloid Interface Sci 2023; 637:182-192. [PMID: 36701864 DOI: 10.1016/j.jcis.2023.01.051] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/24/2022] [Accepted: 01/10/2023] [Indexed: 01/15/2023]
Abstract
HYPOTHESIS It is widely regarded that antimicrobial peptides (AMPs) kill bacteria by physically disrupting microbial membranes and causing cytoplasmic leakage, but it remains unclear how AMPs disrupt the outer membrane (OM) of Gram-negative bacteria (GNB) and then compromise the inner membrane. We hypothesise that different AMPs impose different structural disruptions, with direct implications to their antimicrobial efficacies. EXPERIMENTS The antimicrobial activities of three typical AMPs, including the designed short AMP, G3, and two natural AMPs, melittin and LL37, against E. coli and their haemolytic activities were studied. Lipopolysaccharide (LPS) and anionic di-palmitoyl phosphatidyl glycerol (DPPG) monolayer models were constructed to mimic the outer membrane and inner membrane leaflets of Gram-negative bacteria. The binding and penetration of AMPs to the model lipid monolayers were systematically studied by neutron reflection via multiple H/D contrast variations. FINDING G3 has relatively high antimicrobial activity, low cytotoxicity, and high proteolytic stability, whilst melittin has significant haemolysis and LL37 has weaker antimicrobial activity. G3 could rapidly lyse LPS and DPPG monolayers within 10-20 min. In contrast, melittin was highly active against the LPS membrane, but the dynamic process lasted up to 80 min, with excessive stacking in the OM. LL37 caused rather weak destruction to LPS and DPPG monolayers, leading to massive adsorption on the membrane surface without penetrating the lipid tail region. These findings demonstrate that the rationally designed AMP G3 was well optimised to impose most effective destruction to bacterial membranes, consistent with its highest bactericidal activity. These different interfacial structural features associated with AMP binding shed light on the future development of active and biocompatible AMPs for infection and wound treatments.
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Affiliation(s)
- Haoning Gong
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK; State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China
| | - Xuzhi Hu
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK
| | - Lin Zhang
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK
| | - Ke Fa
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK
| | - Mingrui Liao
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK
| | - Huayang Liu
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK
| | | | - Mario Campana
- ISIS Pulsed Neutron & Muon Source, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | - Jian Ren Lu
- Biological Physics Laboratory, Department of Physics and Astronomy, Faculty of Science and Engineering, The University of Manchester, Manchester M13 9PL, UK.
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3
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Robinson MJ, Newbury S, Singh K, Leonenko Z, Beazely MA. The Interplay Between Cholesterol and Amyloid-β on HT22 Cell Viability, Morphology, and Receptor Tyrosine Kinase Signaling. J Alzheimers Dis 2023; 96:1663-1683. [PMID: 38073391 DOI: 10.3233/jad-230753] [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] [Indexed: 12/18/2023]
Abstract
BACKGROUND There is a lack of understanding in the molecular and cellular mechanisms of Alzheimer's disease that has hindered progress on therapeutic development. The focus has been on targeting toxic amyloid-β (Aβ) pathology, but these therapeutics have generally failed in clinical trials. Aβ is an aggregation-prone protein that has been shown to disrupt cell membrane structure in molecular biophysics studies and interfere with membrane receptor signaling in cell and animal studies. Whether the lipid membrane or specific receptors are the primary target of attack has not been determined. OBJECTIVE This work elucidates some of the interplay between membrane cholesterol and Aβ42 on HT22 neuronal cell viability, morphology, and platelet-derived growth factor (PDGF) signaling pathways. METHODS The effects of cholesterol depletion by methyl-β-cyclodextrin followed by treatment with Aβ and/or PDGF-AA were assessed by MTT cell viability assays, western blot, optical and AFM microscopy. RESULTS Cell viability studies show that cholesterol depletion was mildly protective against Aβ toxicity. Together cholesterol reduction and Aβ42 treatment compounded the disruption of the PDGFα receptor activation. Phase contrast optical microscopy and live cell atomic force microscopy imaging revealed that cytotoxic levels of Aβ42 caused morphological changes including cell membrane damage, cytoskeletal disruption, and impaired cell adhesion; cell damage was ameliorated by cellular cholesterol depletion. CONCLUSIONS Cholesterol depletion impacted the effects of Aβ42 on HT22 cell viability, morphology, and receptor tyrosine kinase signaling.
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Affiliation(s)
- Morgan J Robinson
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
- Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, Canada
| | - Sean Newbury
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
| | - Kartar Singh
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
| | - Zoya Leonenko
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, Canada
- Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, Canada
| | - Michael A Beazely
- School of Pharmacy, University of Waterloo, Waterloo, ON, Canada
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
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4
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Fu L, Li X, Zhang S, Dong Y, Fang W, Gao L. Polymyxins induce lipid scrambling and disrupt the homeostasis of Gram-negative bacteria membrane. Biophys J 2022; 121:3486-3498. [PMID: 35964158 PMCID: PMC9515121 DOI: 10.1016/j.bpj.2022.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/01/2022] [Accepted: 08/10/2022] [Indexed: 11/30/2022] Open
Abstract
Polymyxins are increasingly used as the last-line therapeutic option for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. However, efforts to address the resistance in superbugs are compromised by a poor understanding of the bactericidal modes because high-resolution detection of the cell structure is still lacking. By performing molecular dynamics simulations at a coarse-grained level, here we show that polymyxin B (PmB) disrupts Gram-negative bacterial membranes by altering lipid homeostasis and asymmetry. We found that the binding of PmBs onto the asymmetric outer membrane (OM) loosens the packing of lipopolysaccharides (LPS) and induces unbalanced bending torque between the inner and outer leaflets, which in turn triggers phospholipids to flip from the inner leaflet to the outer leaflet to compensate for the stress deformation. Meanwhile, some LPSs may be detained on the inner membrane (IM). Then, the lipid-scrambled OM undergoes phase separation. Defects are created at the boundaries between LPS-rich domains and phospholipid-rich domains, which consequently facilitate the uptake of PmB across the OM. Finally, PmBs target LPSs detained on the IM and similarly perturb the IM. This lipid Scramble, membrane phase Separation, and peptide Translocation model depicts a novel mechanism by which polymyxins kill bacteria and sheds light on developing a new generation of polymyxins or antibiotic adjuvants with improved killing activities and higher therapeutic indices.
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Affiliation(s)
- Lei Fu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Xiangyuan Li
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Shan Zhang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Yi Dong
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Weihai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Lianghui Gao
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China.
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5
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Yin M, Liu C, Ge R, Fang Y, Wei J, Chen X, Chen Q, Chen X. Paper-supported near-infrared-light-triggered photoelectrochemical platform for monitoring Escherichia coli O157:H7 based on silver nanoparticles-sensitized-upconversion nanophosphors. Biosens Bioelectron 2022; 203:114022. [DOI: 10.1016/j.bios.2022.114022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 11/26/2021] [Accepted: 01/17/2022] [Indexed: 12/14/2022]
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6
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Unravelling the structural complexity of protein-lipid interactions with neutron reflectometry. Biochem Soc Trans 2021; 49:1537-1546. [PMID: 34240735 DOI: 10.1042/bst20201071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 06/02/2021] [Accepted: 06/14/2021] [Indexed: 11/17/2022]
Abstract
Neutron reflectometry (NR) is a large-facility technique used to examine structure at interfaces. In this brief review an introduction to the utilisation of NR in the study of protein-lipid interactions is given. Cold neutron beams penetrate matter deeply, have low energies, wavelengths in the Ångstrom regime and are sensitive to light elements. High differential hydrogen sensitivity (between protium and deuterium) enables solution and sample isotopic labelling to be utilised to enhance or diminish the scattering signal of individual components within complex biological structures. The combination of these effects means NR can probe buried structures such as those at the solid-liquid interface and encode molecular level structural information on interfacial protein-lipid complexes revealing the relative distribution of components as well as the overall structure. Model biological membrane sample systems can be structurally probed to examine phenomena such as antimicrobial mode of activity, as well as structural and mechanistic properties peripheral/integral proteins within membrane complexes. Here, the example of the antimicrobial protein α1-purothionin binding to a model Gram negative bacterial outer membrane is used to highlight the utilisation of this technique, detailing how changes in the protein/lipid distributions across the membrane before and after the protein interaction can be easily encoded using hydrogen isotope labelling.
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7
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Chakraborty A, Kobzev E, Chan J, de Zoysa GH, Sarojini V, Piggot TJ, Allison JR. Molecular Dynamics Simulation of the Interaction of Two Linear Battacin Analogs with Model Gram-Positive and Gram-Negative Bacterial Cell Membranes. ACS OMEGA 2021; 6:388-400. [PMID: 33458490 PMCID: PMC7807746 DOI: 10.1021/acsomega.0c04752] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/08/2020] [Indexed: 06/12/2023]
Abstract
Antimicrobial peptides (AMPs) are a potential solution to the increasing threat of antibiotic resistance, but successful design of active but nontoxic AMPs requires understanding their mechanism of action. Molecular dynamics (MD) simulations can provide atomic-level information regarding how AMPs interact with the cell membrane. Here, we have used MD simulations to study two linear analogs of battacin, a naturally occurring cyclic, lipidated, nonribosomal AMP. Like battacin, these analogs are active against Gram-negative multidrug resistant and Gram-positive bacteria, but they are less toxic than battacin. Our simulations show that this activity depends upon a combination of positively charged and hydrophobic moieties. Favorable interactions with negatively charged membrane lipid head groups drive association with the membrane and insertion of hydrophobic residues, and the N-terminal lipid anchors the peptides to the membrane surface. Both effects are required for stable membrane binding.
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Affiliation(s)
- Aparajita Chakraborty
- Maurice
Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 1010, New Zealand
- School
of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
- Centre
for Theoretical Chemistry and Physics, Massey
University Auckland, Auckland 0632, New Zealand
| | - Elisey Kobzev
- Maurice
Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 1010, New Zealand
- Centre
for Theoretical Chemistry and Physics, Massey
University Auckland, Auckland 0632, New Zealand
- School
of Computational and Natural Sciences, Massey
University Auckland, Auckland 0632, New Zealand
| | - Jonathan Chan
- School
of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
- Department
of Biochemistry, University of Oxford, South Parks Rd, Oxford OX1 3QU, United
Kingdom
| | | | - Vijayalekshmi Sarojini
- School of
Chemical Sciences, University of Auckland, Auckland 1010, New Zealand
- MacDiarmid
Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6140, New Zealand
| | - Thomas J. Piggot
- School
of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
- Chemical
Biological and Radiological Sciences, Defence
Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, United Kingdom
| | - Jane R Allison
- Maurice
Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 1010, New Zealand
- School
of Biological Sciences, University of Auckland, Auckland 1010, New Zealand
- Centre
for Theoretical Chemistry and Physics, Massey
University Auckland, Auckland 0632, New Zealand
- Biomolecular
Interaction Centre, University of Canterbury, Christchurch 8041, New Zealand
- Digital
Life Institute, University of Auckland, Auckland 1010, New Zealand
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8
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Qian S, Sharma VK, Clifton LA. Understanding the Structure and Dynamics of Complex Biomembrane Interactions by Neutron Scattering Techniques. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:15189-15211. [PMID: 33300335 DOI: 10.1021/acs.langmuir.0c02516] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The membrane is one of the key structural materials of biology at the cellular level. Composed predominantly of a bilayer of lipids with embedded and bound proteins, it defines the boundaries of the cell and many organelles essential to life and therefore is involved in almost all biological processes. Membrane-specific interactions, such as drug binding to a membrane receptor or the interactions of an antimicrobial compound with the lipid matrix of a pathogen membrane, are of interest across the scientific disciplines. Herein we present a review, aimed at nonexperts, of the major neutron scattering techniques used in membrane studies: small-angle neutron scattering, neutron membrane diffraction, neutron reflectometry, quasielastic neutron scattering, and neutron spin echo. Neutron scattering techniques are well suited to studying biological membranes. The nondestructive nature of cold neutrons means that samples can be measured for long periods without fear of beam damage from ultraviolet, electron, or X-ray radiation, and neutron beams are highly penetrating, thus offering flexibility in samples and sample environments. Most important is the strong difference in neutron scattering lengths between the two most abundant forms of hydrogen, protium and deuterium. Changing the relative amounts of protium/deuterium in a sample allows the production of a series of neutron scattering data sets, enabling the observation of differing components within complex membrane architectures. This approach can be as simple as using the naturally occurring neutron contrast between different biomolecules to study components in a complex by changing the solution H2O/D2O ratio or as complex as selectively labeling individual components with hydrogen isotopes. This review presents an overview of each experimental technique with the neutron instrument configuration, related sample preparation and sample environment, and data analysis, highlighted by a special emphasis on using prominent neutron contrast to understand structure and dynamics. This review gives researchers a practical introduction to the often enigmatic suite of neutron beamlines, thereby lowering the barrier to taking advantage of these large-facility techniques to achieve new understandings of membranes and their interactions with other molecules.
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Affiliation(s)
- Shuo Qian
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Veerendra Kumar Sharma
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - Luke A Clifton
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, U.K. OX11 0QX
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9
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Rathnayake K, Patel U, Pham C, McAlpin A, Budisalich T, Jayawardena SN. Targeted Delivery of Antibiotic Therapy to Inhibit Pseudomonas aeruginosa Using Lipid-Coated Mesoporous Silica Core–Shell Nanoassembly. ACS APPLIED BIO MATERIALS 2020; 3:6708-6721. [DOI: 10.1021/acsabm.0c00622] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kavini Rathnayake
- Department of Chemistry, The University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
| | - Unnati Patel
- Department of Chemistry, The University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
| | - Chi Pham
- Department of Chemistry, The University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
| | - Anna McAlpin
- Department of Chemistry, The University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
| | - Travis Budisalich
- Department of Chemistry, The University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
| | - Surangi N. Jayawardena
- Department of Chemistry, The University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
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10
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Pardoux É, Boturyn D, Roupioz Y. Antimicrobial Peptides as Probes in Biosensors Detecting Whole Bacteria: A Review. Molecules 2020; 25:E1998. [PMID: 32344585 PMCID: PMC7221689 DOI: 10.3390/molecules25081998] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/23/2020] [Accepted: 04/23/2020] [Indexed: 12/17/2022] Open
Abstract
Bacterial resistance is becoming a global issue due to its rapid growth. Potential new drugs as antimicrobial peptides (AMPs) are considered for several decades as promising candidates to circumvent this threat. Nonetheless, AMPs have also been used more recently in other settings such as molecular probes grafted on biosensors able to detect whole bacteria. Rapid, reliable and cost-efficient diagnostic tools for bacterial infection could prevent the spread of the pathogen from the earliest stages. Biosensors based on AMPs would enable easy monitoring of potentially infected samples, thanks to their powerful versatility and integrability in pre-existent settings. AMPs, which show a broad spectrum of interactions with bacterial membranes, can be tailored in order to design ubiquitous biosensors easily adaptable to clinical settings. This review aims to focus on the state of the art of AMPs used as the recognition elements of whole bacteria in label-free biosensors with a particular focus on the characteristics obtained in terms of threshold, volume of sample analysable and medium, in order to assess their workability in real-world applications.
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Affiliation(s)
- Éric Pardoux
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, SyMMES, 38000 Grenoble, France;
- Univ. Grenoble Alpes, CNRS, DCM, 38000 Grenoble, France;
| | - Didier Boturyn
- Univ. Grenoble Alpes, CNRS, DCM, 38000 Grenoble, France;
| | - Yoann Roupioz
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, SyMMES, 38000 Grenoble, France;
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11
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Clifton LA, Campbell RA, Sebastiani F, Campos-Terán J, Gonzalez-Martinez JF, Björklund S, Sotres J, Cárdenas M. Design and use of model membranes to study biomolecular interactions using complementary surface-sensitive techniques. Adv Colloid Interface Sci 2020; 277:102118. [PMID: 32044469 DOI: 10.1016/j.cis.2020.102118] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/24/2020] [Accepted: 01/29/2020] [Indexed: 01/07/2023]
Abstract
Cellular membranes are complex structures and simplified analogues in the form of model membranes or biomembranes are used as platforms to understand fundamental properties of the membrane itself as well as interactions with various biomolecules such as drugs, peptides and proteins. Model membranes at the air-liquid and solid-liquid interfaces can be studied using a range of complementary surface-sensitive techniques to give a detailed picture of both the structure and physicochemical properties of the membrane and its resulting interactions. In this review, we will present the main planar model membranes used in the field to date with a focus on monolayers at the air-liquid interface, supported lipid bilayers at the solid-liquid interface and advanced membrane models such as tethered and floating membranes. We will then briefly present the principles as well as the main type of information on molecular interactions at model membranes accessible using a Langmuir trough, quartz crystal microbalance with dissipation monitoring, ellipsometry, atomic force microscopy, Brewster angle microscopy, Infrared spectroscopy, and neutron and X-ray reflectometry. A consistent example for following biomolecular interactions at model membranes is used across many of the techniques in terms of the well-studied antimicrobial peptide Melittin. The overall objective is to establish an understanding of the information accessible from each technique, their respective advantages and limitations, and their complementarity.
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Affiliation(s)
- Luke A Clifton
- ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 OQX, United Kingdom
| | - Richard A Campbell
- Division of Pharmacy and Optometry, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Federica Sebastiani
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - José Campos-Terán
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Av. Vasco de Quiroga 4871, Col. Santa Fe, Delegación Cuajimalpa de Morelos, 05348, Mexico; Lund Institute of advanced Neutron and X-ray Science, Lund University, Scheelevägen 19, 223 70 Lund, Sweden
| | - Juan F Gonzalez-Martinez
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - Sebastian Björklund
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - Javier Sotres
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden
| | - Marité Cárdenas
- Department of Biomedical Science and Biofilms - Research Center for Biointerfaces, Malmö University, 20506 Malmö, Sweden.
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12
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Della Pelle G, Perà G, Belardinelli MC, Gerdol M, Felli M, Crognale S, Scapigliati G, Ceccacci F, Buonocore F, Porcelli F. Trematocine, a Novel Antimicrobial Peptide from the Antarctic Fish Trematomus bernacchii: Identification and Biological Activity. Antibiotics (Basel) 2020; 9:E66. [PMID: 32041161 PMCID: PMC7168153 DOI: 10.3390/antibiotics9020066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/03/2020] [Accepted: 02/05/2020] [Indexed: 01/02/2023] Open
Abstract
Antimicrobial peptides (AMPs) are short peptides active against a wide range of pathogens and, therefore, they are considered a useful alternative to conventional antibiotics. We have identified a new AMP in a transcriptome derived from the Antarctic fish Trematomus bernacchii. This peptide, named Trematocine, has been investigated for its expression both at the basal level and after in vivo immunization with an endemic Antarctic bacterium (Psychrobacter sp. TAD1). Results agree with the expected behavior of a fish innate immune component, therefore we decided to synthesize the putative mature sequence of Trematocine to determine the structure, the interaction with biological membranes, and the biological activity. We showed that Trematocine folds into a α-helical structure in the presence of both zwitterionic and anionic charged vesicles. We demonstrated that Trematocine has a highly specific interaction with anionic charged vesicles and that it can kill Gram-negative bacteria, possibly via a carpet like mechanism. Moreover, Trematocine showed minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against selected Gram-positive and Gram-negative bacteria similar to other AMPs isolated from Antarctic fishes. The peptide is a possible candidate for a new drug as it does not show any haemolytic or cytotoxic activity against mammalian cells at the concentration needed to kill the tested bacteria.
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Affiliation(s)
- Giulia Della Pelle
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Giulia Perà
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Maria Cristina Belardinelli
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Marco Gerdol
- Department of Life Sciences, University of Trieste, Trieste 34128, Italy;
| | - Martina Felli
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Silvia Crognale
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Giuseppe Scapigliati
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Francesca Ceccacci
- CNR—Institute for Biological Systems, Sede Secondaria di Roma-Meccanismi di Reazione, 00185 Rome, Italy;
| | - Francesco Buonocore
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
| | - Fernando Porcelli
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, 01100 Viterbo, Italy; (G.D.P.); (G.P.); (M.C.B.); (M.F.); (S.C.); (G.S.); (F.P.)
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13
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Yang G, Wang H, Dong Y, Li Z, Wang GL. High-throughput photoelectrochemical determination of E. coli O157:H7 by modulation of the anodic photoelectrochemistry of CdS quantum dots via reversible deposition of MnO2. Mikrochim Acta 2019; 187:16. [DOI: 10.1007/s00604-019-3968-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 10/19/2019] [Indexed: 12/14/2022]
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14
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The pH-dependence of lipid-mediated antimicrobial peptide resistance in a model staphylococcal plasma membrane: A two-for-one mechanism of epithelial defence circumvention. Eur J Pharm Sci 2019; 128:43-53. [DOI: 10.1016/j.ejps.2018.11.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/21/2018] [Accepted: 11/18/2018] [Indexed: 11/18/2022]
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15
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Marine Antimicrobial Peptides: A Promising Source of New Generation Antibiotics and Other Bio-active Molecules. Int J Pept Res Ther 2018. [DOI: 10.1007/s10989-018-9789-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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16
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Fitriyanti M, Narsimhan G. Synergistic effect of low power ultrasonication on antimicrobial activity of cecropin P1 against E. coli in food systems. Lebensm Wiss Technol 2018. [DOI: 10.1016/j.lwt.2018.05.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Petkov P, Marinova R, Kochev V, Ilieva N, Lilkova E, Litov L. Computational study of solution behavior of magainin 2 monomers. J Biomol Struct Dyn 2018; 37:1231-1240. [PMID: 29557267 DOI: 10.1080/07391102.2018.1454850] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Antimicrobial peptides (AMPs) play crucial role as mediators of the primary host defense against microbial invasion. They are considered a promising alternative to antibiotics for multidrug resistant bacterial strains. For complete understanding of the antimicrobial defense mechanism, a detailed knowledge of the dynamics of peptide-membrane interactions, including atomistic studies on AMPs geometry and both peptide and membrane structural changes during the whole process is a prerequisite. We aim at clarifying the conformation dynamics of small linear AMPs in solution as a first step of in silico protocol for establishing a correspondence between certain amino-acid sequence motifs, secondary-structure elements, conformational dynamics in solution and the intensity and mode of interaction with the bacterial membrane. To this end, we use molecular dynamics simulations augmented by well-tempered metadynamics to study the free-energy landscape of two AMPs with close primary structure and different antibacterial activity - the native magainin 2 (MG2) and an analog (MG2m, with substitutions F5Y and F16W) in aqueous solution. We observe that upon solvation, the initial α-helical structures change differently. The native form remains structured, with three shorter α-helical motifs, connected by random coils, while the synthetic analog tends predominantly to a disordered conformation. Our results indicate the importance of the side-chains at positions 5 and 16 for maintaining the solvated peptide conformation. They also provide a modeling background for recent experimental observations, relating the higher α-helical content in solution (peptide pre-folding) in the case of small linear AMPs to a lower antibacterial activity.
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Key Words
- AA, Amino Acid
- AAS, Amino Acid Sequence
- AMP, Antimicrobial Peptides
- CV, Collective Variable
- FF, Force Field
- MD, Molecular Dynamics
- MG2, Magainin 2
- MG2m, (F5Y, F16W)-magainin 2 analog
- PC, Principal Component
- PCA, Principal Component Analysis
- PMF, Potential of Mean Force
- antimicrobial peptides (AMPs)
- computational study
- conformational dynamics
- free-energy landscape
- magainin 2 (MG2)
- molecular dynamics simulations
- point mutation
- solvated peptide behavior
- well-tempered metadynamics
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Affiliation(s)
- P Petkov
- a Faculty of Physics , Sofia University "St. Kl. Ohridski" , Sofia , Bulgaria
| | - R Marinova
- a Faculty of Physics , Sofia University "St. Kl. Ohridski" , Sofia , Bulgaria
| | - V Kochev
- a Faculty of Physics , Sofia University "St. Kl. Ohridski" , Sofia , Bulgaria
| | - N Ilieva
- b Institute of Information and Communication Technologies , Bulgarian Academy of Sciences , Sofia , Bulgaria
| | - E Lilkova
- b Institute of Information and Communication Technologies , Bulgarian Academy of Sciences , Sofia , Bulgaria
| | - L Litov
- a Faculty of Physics , Sofia University "St. Kl. Ohridski" , Sofia , Bulgaria
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18
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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.
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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.)
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19
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Wilde M, Green RJ, Sanders MR, Greco F. Biophysical studies in polymer therapeutics: the interactions of anionic and cationic PAMAM dendrimers with lipid monolayers. J Drug Target 2017; 25:910-918. [DOI: 10.1080/1061186x.2017.1365877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Marleen Wilde
- School of Pharmacy, University of Reading, Reading, UK
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20
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Rehal RP, Marbach H, Hubbard AT, Sacranie AA, Sebastiani F, Fragneto G, Harvey RD. The influence of mild acidity on lysyl-phosphatidylglycerol biosynthesis and lipid membrane physico-chemical properties in methicillin-resistant Staphylococcus aureus. Chem Phys Lipids 2017. [DOI: 10.1016/j.chemphyslip.2017.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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21
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Menzel LP, Chowdhury HM, Masso-Silva JA, Ruddick W, Falkovsky K, Vorona R, Malsbary A, Cherabuddi K, Ryan LK, DiFranco KM, Brice DC, Costanzo MJ, Weaver D, Freeman KB, Scott RW, Diamond G. Potent in vitro and in vivo antifungal activity of a small molecule host defense peptide mimic through a membrane-active mechanism. Sci Rep 2017; 7:4353. [PMID: 28659617 PMCID: PMC5489528 DOI: 10.1038/s41598-017-04462-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 05/17/2017] [Indexed: 12/28/2022] Open
Abstract
Lethal systemic fungal infections of Candida species are increasingly common, especially in immune compromised patients. By in vitro screening of small molecule mimics of naturally occurring host defense peptides (HDP), we have identified several active antifungal molecules, which also exhibited potent activity in two mouse models of oral candidiasis. Here we show that one such compound, C4, exhibits a mechanism of action that is similar to the parent HDP upon which it was designed. Specifically, its initial interaction with the anionic microbial membrane is electrostatic, as its fungicidal activity is inhibited by cations. We observed rapid membrane permeabilization to propidium iodide and ATP efflux in response to C4. Unlike the antifungal peptide histatin 5, it did not require energy-dependent transport across the membrane. Rapid membrane disruption was observed by both fluorescence and electron microscopy. The compound was highly active in vitro against numerous fluconazole-resistant clinical isolates of C. albicans and non-albicans species, and it exhibited potent, dose-dependent activity in a mouse model of invasive candidiasis, reducing kidney burden by three logs after 24 hours, and preventing mortality for up to 17 days. Together the results support the development of this class of antifungal drug to treat invasive candidiasis.
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Affiliation(s)
- Lorenzo P Menzel
- Department of Oral Biology, University of Florida, Gainesville, FL, 32610, USA
| | | | - Jorge Adrian Masso-Silva
- Graduate School of Biomedical Sciences, New Jersey Medical School, Rutgers, Newark, NJ, 07101, USA
| | - William Ruddick
- Department of Oral Biology, University of Florida, Gainesville, FL, 32610, USA
| | - Klaudia Falkovsky
- Department of Oral Biology, New Jersey Dental School, Rutgers, Newark, NJ, 07101, USA
| | - Rafael Vorona
- Department of Oral Biology, University of Florida, Gainesville, FL, 32610, USA
| | - Andrew Malsbary
- Department of Oral Biology, New Jersey Dental School, Rutgers, Newark, NJ, 07101, USA
| | - Kartikeya Cherabuddi
- Division of Infectious Diseases and Global Medicine, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, 32610, USA
| | - Lisa K Ryan
- Division of Infectious Diseases and Global Medicine, Department of Medicine, University of Florida College of Medicine, Gainesville, FL, 32610, USA
| | - Kristina M DiFranco
- Department of Oral Biology, University of Florida, Gainesville, FL, 32610, USA
| | - David C Brice
- Department of Oral Biology, University of Florida, Gainesville, FL, 32610, USA
| | | | - Damian Weaver
- Fox Chase Chemical Diversity Center, Doylestown, PA, USA
| | | | | | - Gill Diamond
- Department of Oral Biology, University of Florida, Gainesville, FL, 32610, USA.
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22
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Sanders MR, Clifton LA, Frazier RA, Green RJ. Tryptophan to Arginine Substitution in Puroindoline-b Alters Binding to Model Eukaryotic Membrane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4847-4853. [PMID: 28448148 DOI: 10.1021/acs.langmuir.6b03030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We have studied how puroindoline-b (PINB) mutants bind to model eukaryotic membranes dependent on binary composition of anionic:zwitterionic phospholipids and the presence of cholesterol and sphingomyelin in the model membrane. We have found that the trends in lipid binding behavior are different for wild-type PINB compared to its naturally occurring PINB(Trp44Arg) mutant form and have seen evidence of protein-induced domain formation within the lipid layer structure. Results show that selective binding of antimicrobial peptides to different membrane types is as a result of differences in lipid composition and the arrangement of lipids within the membrane surface. However, membrane-binding behavior is not easily predicted; it is determined by net charge, hydrophobicity, and the amphiphilicity of the protein/peptide lipid-binding domain.
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Affiliation(s)
- Michael R Sanders
- School of Pharmacy and Department of Food and Nutritional Sciences, University of Reading , PO Box 226, Whiteknights, Reading, Berkshire RG6 6AP, U.K
| | - Luke A Clifton
- ISIS Pulsed Neutron and Muon Source, Science and technology Facilities Council, Rutherford Appleton Laboratory , Harwell Oxford Campus, Didcot, Oxfordshire OX11 0QX, U.K
| | - Richard A Frazier
- School of Pharmacy and Department of Food and Nutritional Sciences, University of Reading , PO Box 226, Whiteknights, Reading, Berkshire RG6 6AP, U.K
| | - Rebecca J Green
- School of Pharmacy and Department of Food and Nutritional Sciences, University of Reading , PO Box 226, Whiteknights, Reading, Berkshire RG6 6AP, U.K
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23
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Ciumac D, Campbell RA, Xu H, Clifton LA, Hughes AV, Webster JR, Lu JR. Implications of lipid monolayer charge characteristics on their selective interactions with a short antimicrobial peptide. Colloids Surf B Biointerfaces 2017; 150:308-316. [DOI: 10.1016/j.colsurfb.2016.10.043] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 10/10/2016] [Accepted: 10/24/2016] [Indexed: 10/20/2022]
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24
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Hicks R. Preparation of Membrane Models of Gram-Negative Bacteria and Their Interaction with Antimicrobial Peptides Studied by CD and NMR. Methods Mol Biol 2017; 1548:231-245. [PMID: 28013508 DOI: 10.1007/978-1-4939-6737-7_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The antibiotic activity of antimicrobial peptides is generally derived via some type of disruption of the cell membrane(s). The most common models used to mimic the properties of bacterial membranes consist of mixtures of various zwitterionic and anionic phospholipids. This approach works reasonably well for Gram-positive bacteria. However, since the membranes of Gram-negative bacteria contain lipopolysaccharides, as well as zwitterionic and anionic phospholipids, a more complex model is required to simulate the outer membrane of Gram-negative bacteria. Herein we present a protocol for the preparation of models of the outer membranes of the Gram-negative bacteria Klebsiella pneumoniae and Pseudomonas aeruginosa. This protocol can be used to prepare models of other Gram-negative bacteria provided the strain-specific lipopolysaccharides are available.
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Affiliation(s)
- Rickey Hicks
- Department of Chemistry and Physics, College of Science and Mathematics, Augusta University, 1120 5th Street, Augusta, GA, 30912, USA.
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25
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Knyght I, Clifton L, Saaka Y, Lawrence MJ, Barlow DJ. Interaction of the Antimicrobial Peptides Rhesus θ-Defensin and Porcine Protegrin-1 with Anionic Phospholipid Monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:7403-10. [PMID: 27357217 DOI: 10.1021/acs.langmuir.6b01688] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A combination of Langmuir isotherm, Brewster angle microscopy (BAM), and neutron reflectivity studies have been performed to gain insight into the effects on model bacterial cell membranes of the antimicrobial peptides, Rhesus θ-defensin 1 (RTD-1), and porcine protegrin 1 (PG-1). The peptides were interacted with monolayers spread at the air-water interface and prepared from a 3:1 molar mixture of phosphatidylethanolamine and phosphatidylglycerol used to approximate the cell membranes of Gram positive bacteria. The Langmuir film balance measurements show that both peptides perturb the lipid monolayers causing an increase in surface pressure, and the BAM studies show that each results in the formation of small domains within the lipid films, around 5 μm diameter. The overall change in monolayer surface pressure caused by PG-1, however, is a little more pronounced than that due to RTD-1 (+8.5 mN·m(-1) vs +5.5 mN·m(-1)), and the rate of its initial interaction with the monolayer is a little more rapid than that for RTD-1. The neutron reflectivity studies also show differences for PG-1 and RTD-1, with the model fits to these data showing that the more amphiphilic PG-1 becomes fully embedded within the lipid film-causing an extension of the lipid acyl chains but leaving the thickness of the lipid headgroup layer unaffected-while RTD-1 is seen to insert less deeply-causing the same extension of the lipid acyl chains as PG-1 but also causing a significant increase in thickness of the lipid headgroup layer. The various differing effects of the two peptides on anionic lipid monolayers are discussed in the context of their differing hemolytic activities, and their proposed differing propensities to form transmembrane pores.
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Affiliation(s)
- Ivana Knyght
- Institute of Pharmaceutical Science, King's College London , London SE1 9NH, United Kingdom
| | - Luke Clifton
- Rutherford Appleton Laboratory, ISIS Spallation Neutron Source, Harwell OX11 0QX, United Kingdom
| | - Yussif Saaka
- Institute of Pharmaceutical Science, King's College London , London SE1 9NH, United Kingdom
| | - M Jayne Lawrence
- Institute of Pharmaceutical Science, King's College London , London SE1 9NH, United Kingdom
| | - David J Barlow
- Institute of Pharmaceutical Science, King's College London , London SE1 9NH, United Kingdom
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26
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Juhaniewicz J, Sek S. Interaction of Melittin with Negatively Charged Lipid Bilayers Supported on Gold Electrodes. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2015.11.134] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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27
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One-step synthesis of high-density peptide-conjugated gold nanoparticles with antimicrobial efficacy in a systemic infection model. Biomaterials 2016; 85:99-110. [DOI: 10.1016/j.biomaterials.2016.01.051] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/31/2015] [Accepted: 01/26/2016] [Indexed: 11/20/2022]
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28
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Sanders MR, Clifton LA, Frazier RA, Green RJ. Role of Lipid Composition on the Interaction between a Tryptophan-Rich Protein and Model Bacterial Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:2050-7. [PMID: 26813886 DOI: 10.1021/acs.langmuir.5b04628] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The interaction between tryptophan-rich puroindoline proteins and model bacterial membranes at the air-liquid interface has been investigated by FTIR spectroscopy, surface pressure measurements, and Brewster angle microscopy. The role of different lipid constituents on the interactions between lipid membrane and protein was studied using wild type (Pin-b) and mutant (Trp44 to Arg44 mutant, Pin-bs) puroindoline proteins. The results show differences in the lipid selectivity of the two proteins in terms of preferential binding to specific lipid head groups in mixed lipid systems. Pin-b wild type was able to penetrate mixed layers of phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) head groups more deeply compared to the mutant Pin-bs. Increasing saturation of the lipid tails increased penetration and adsorption of Pin-b wild type, but again the response of the mutant form differed. The results provide insight as to the role of membrane architecture, lipid composition, and fluidity on antimicrobial activity of proteins. Data show distinct differences in the lipid binding behavior of Pin-b as a result of a single residue mutation, highlighting the importance of hydrophobic and charged amino acids in antimicrobial protein and peptide activity.
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Affiliation(s)
- Michael R Sanders
- School of Pharmacy and Department of Food and Nutritional Sciences, University of Reading , PO Box 226, Whiteknights, Reading, Berkshire RG6 6AP, United Kingdom
| | - Luke A Clifton
- ISIS Pulsed Neutron and Muon Source, Science and technology Facilities Council, Rutherford Appleton Laboratory , Harwell Oxford Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Richard A Frazier
- School of Pharmacy and Department of Food and Nutritional Sciences, University of Reading , PO Box 226, Whiteknights, Reading, Berkshire RG6 6AP, United Kingdom
| | - Rebecca J Green
- School of Pharmacy and Department of Food and Nutritional Sciences, University of Reading , PO Box 226, Whiteknights, Reading, Berkshire RG6 6AP, United Kingdom
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29
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The influence of rough lipopolysaccharide structure on molecular interactions with mammalian antimicrobial peptides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:197-209. [DOI: 10.1016/j.bbamem.2015.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 11/03/2015] [Accepted: 11/12/2015] [Indexed: 11/21/2022]
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30
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Du H, Samuel RL, Massiah MA, Gillmor SD. The structure and behavior of the NA-CATH antimicrobial peptide with liposomes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015. [DOI: 10.1016/j.bbamem.2015.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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31
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Jamasbi E, Ciccotosto GD, Tailhades J, Robins-Browne RM, Ugalde CL, Sharples RA, Patil N, Wade JD, Hossain MA, Separovic F. Site of fluorescent label modifies interaction of melittin with live cells and model membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:2031-9. [PMID: 26051124 DOI: 10.1016/j.bbamem.2015.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 05/30/2015] [Accepted: 06/02/2015] [Indexed: 02/01/2023]
Abstract
The mechanism of membrane disruption by melittin (MLT) of giant unilamellar vesicles (GUVs) and live cells was studied using fluorescence microscopy and two fluorescent synthetic analogues of MLT. The N-terminus of one of these was acylated with thiopropionic acid to enable labeling with maleimido-AlexaFluor 430 to study the interaction of MLT with live cells. It was compared with a second analogue labeled at P14C. The results indicated that the fluorescent peptides adhered to the membrane bilayer of phosphatidylcholine GUVs and inserted into the plasma membrane of HeLa cells. Fluorescence and light microscopy revealed changes in cell morphology after exposure to MLT peptides and showed bleb formation in the plasma membrane of HeLa cells. However, the membrane disruptive effect was dependent upon the location of the fluorescent label on the peptide and was greater when MLT was labeled at the N-terminus. Proline at position 14 appeared to be important for antimicrobial activity, hemolysis and cytotoxicity, but not essential for cell membrane disruption.
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Affiliation(s)
- Elaheh Jamasbi
- School of Chemistry, Bio21 Institute, The University of Melbourne, VIC 3010, Australia
| | | | - Julien Tailhades
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC 3010, Australia
| | - Roy M Robins-Browne
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, VIC 3010, Australia; Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, VIC 3052, Australia
| | - Cathryn L Ugalde
- Department of Biochemistry & Molecular Biology, Bio21 Institute, The University of Melbourne, VIC 3010, Australia
| | - Robyn A Sharples
- Department of Biochemistry & Molecular Biology, Bio21 Institute, The University of Melbourne, VIC 3010, Australia
| | - Nitin Patil
- School of Chemistry, Bio21 Institute, The University of Melbourne, VIC 3010, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC 3010, Australia
| | - John D Wade
- School of Chemistry, Bio21 Institute, The University of Melbourne, VIC 3010, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC 3010, Australia
| | - Mohammed Akhter Hossain
- School of Chemistry, Bio21 Institute, The University of Melbourne, VIC 3010, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC 3010, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, The University of Melbourne, VIC 3010, Australia
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32
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Berglund NA, Piggot TJ, Jefferies D, Sessions RB, Bond PJ, Khalid S. Interaction of the antimicrobial peptide polymyxin B1 with both membranes of E. coli: a molecular dynamics study. PLoS Comput Biol 2015; 11:e1004180. [PMID: 25885324 PMCID: PMC4401565 DOI: 10.1371/journal.pcbi.1004180] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 02/06/2015] [Indexed: 11/17/2022] Open
Abstract
Antimicrobial peptides are small, cationic proteins that can induce lysis of bacterial cells through interaction with their membranes. Different mechanisms for cell lysis have been proposed, but these models tend to neglect the role of the chemical composition of the membrane, which differs between bacterial species and can be heterogeneous even within a single cell. Moreover, the cell envelope of Gram-negative bacteria such as E. coli contains two membranes with differing compositions. To this end, we report the first molecular dynamics simulation study of the interaction of the antimicrobial peptide, polymyxin B1 with complex models of both the inner and outer membranes of E. coli. The results of >16 microseconds of simulation predict that polymyxin B1 is likely to interact with the membranes via distinct mechanisms. The lipopeptides aggregate in the lipopolysaccharide headgroup region of the outer membrane with limited tendency for insertion within the lipid A tails. In contrast, the lipopeptides readily insert into the inner membrane core, and the concomitant increased hydration may be responsible for bilayer destabilization and antimicrobial function. Given the urgent need to develop novel, potent antibiotics, the results presented here reveal key mechanistic details that may be exploited for future rational drug development.
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Affiliation(s)
- Nils A Berglund
- School of Chemistry, University of Southampton, Highfield, Southampton, United Kingdom; Bioinformatics Institute (A*STAR), Singapore
| | - Thomas J Piggot
- School of Chemistry, University of Southampton, Highfield, Southampton, United Kingdom
| | - Damien Jefferies
- School of Chemistry, University of Southampton, Highfield, Southampton, United Kingdom
| | | | - Peter J Bond
- Bioinformatics Institute (A*STAR), Singapore; Department of Biological Sciences, National University of Singapore, Singapore
| | - Syma Khalid
- School of Chemistry, University of Southampton, Highfield, Southampton, United Kingdom
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Andrade CAS, Nascimento JM, Oliveira IS, de Oliveira CVJ, de Melo CP, Franco OL, Oliveira MDL. Nanostructured sensor based on carbon nanotubes and clavanin A for bacterial detection. Colloids Surf B Biointerfaces 2015; 135:833-839. [PMID: 25847459 DOI: 10.1016/j.colsurfb.2015.03.037] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 03/11/2015] [Accepted: 03/16/2015] [Indexed: 11/17/2022]
Abstract
Unusual methods for specific detection of pathogenic bacteria are becoming key points for control and identification of problems related to health and (bio)safety. In this context, this work aims to propose a new approach for the development of nanostructured biosensors based on carbon nanotubes (CNTs) and antimicrobial peptides for bacterial detection. Firstly, the antimicrobial peptide clavanin A (ClavA) was chemically immobilized on CNTs and surface-immobilized ClavA was used to detect Klebsiella pneumoniae, Enterococcus faecalis, Escherichia coli and Bacillus subtilis in a direct assay format. We used electrochemical impedance spectroscopy technique to evaluate the effectiveness and sensitivity of the ClavA-based biosensors by measuring the modifications in their electrochemical responses before and after incubation in presence of different bacteria concentrations. The biosensor was able to discriminate between bacteria concentrations in the 10(2)-10(6)CFU mL(-1) range. Atomic force microscopy analysis confirmed the biosensor functionality for bacterial recognition. This new sensor system was capable of differentiating between Gram-positive and Gram-negative bacteria, since ClavA showed different affinities toward the pathogenic bacteria species.
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Affiliation(s)
- César A S Andrade
- Programa de Pós-Graduação em Inovação Terapêutica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil; Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
| | - Jéssica M Nascimento
- Programa de Pós-Graduação em Inovação Terapêutica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
| | - Idjane S Oliveira
- Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, 55608-680 Vitória de Santo Antão, PE, Brazil
| | - Carlos V J de Oliveira
- Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
| | - Celso P de Melo
- Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
| | - Octávio L Franco
- Centro de Análise Proteômicas e Bioquímicas de Brasília, Universidade Católica de Brasília, Brasília, DF, Brazil; S-Inova, Pós-graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, MS, Brazil
| | - Maria D L Oliveira
- Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
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Giménez D, Sánchez-Muñoz OL, Salgado J. Direct observation of nanometer-scale pores of melittin in supported lipid monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:3146-58. [PMID: 25705986 DOI: 10.1021/la504293q] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Melittin is the most studied membrane-active peptide and archetype within a large and diverse group of pore formers. However, the molecular characteristics of melittin pores remain largely unknown. Herein, we show by atomic force microscopy (AFM) that lipid monolayers in the presence of melittin are decorated with numerous regularly shaped circular pores that can be distinguished from nonspecific monolayer defects. The specificity of these pores is reinforced through a statistical evaluation of depressions found in Langmuir-Blodgett monolayers in the presence and absence of melittin, which eventually allows characterization of the melittin-induced pores at a quantitative low-resolution level. We observed that the large majority of pores exhibit near-circular symmetry and a Gaussian distribution in size, with a mean diameter of ∼8.7 nm. A distinctive feature is a ring of material found around the pores, made by, on average, three positive peaks, with a height over the level of the lipidic background of ∼0.23 nm. This protruding rim is most likely due to the presence of melittin near the pore border. Although the current resolution of the AFM images in the {x, y} plane does not allow distinction of the specific organization of the peptide molecules, these results provide an unprecedented view of melittin pores formed in lipidic interfaces and open new perspectives for future structural investigations of these and other pore-forming peptides and proteins using supported monolayers.
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Affiliation(s)
- Diana Giménez
- Institute of Molecular Science (ICMol), University of Valencia. C/Catedrático José Beltrán, 2, 46980 Paterna, Valencia, Spain
| | - Orlando L Sánchez-Muñoz
- Institute of Molecular Science (ICMol), University of Valencia. C/Catedrático José Beltrán, 2, 46980 Paterna, Valencia, Spain
| | - Jesús Salgado
- Institute of Molecular Science (ICMol), University of Valencia. C/Catedrático José Beltrán, 2, 46980 Paterna, Valencia, Spain
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Spectral and biological evaluation of a synthetic antimicrobial peptide derived from 1-aminocyclohexane carboxylic acid. Bioorg Med Chem 2015; 23:1341-7. [DOI: 10.1016/j.bmc.2015.01.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 01/04/2015] [Accepted: 01/15/2015] [Indexed: 11/21/2022]
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Label-free detection of pathogenic bacteria via immobilized antimicrobial peptides. Talanta 2015; 137:55-61. [PMID: 25770606 DOI: 10.1016/j.talanta.2015.01.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/06/2015] [Accepted: 01/10/2015] [Indexed: 11/22/2022]
Abstract
A novel label-free strategy for the detection of bacteria was developed by using a specific antimicrobial peptide (AMP)-functionalized quartz crystal microbalance (QCM) electrode. This electrode interface was successfully applied to detect pathogenic Escherichia coli O157:H7 based on the specific affinity between the small synthetic antimicrobial peptide and the bacterial cell of pathogenic E. coli O157:H7. The concentrations of pathogenic E. coli O157:H7 were sensitively measured by the frequency response of the QCM with a detection limit of 0.4 cfu μL(-1). The detection can be fulfilled within 10 min because it does not require germiculture process. On the other hand, if the specific antimicrobial peptides were immobilized on a gold electrode, this label-free strategy can also be performed by electrochemical impedance spectroscopy (EIS). Compared with QCM technique, the EIS measurement gives a lower sensitivity and needs a longer assay time. The combination of antimicrobial peptides with the real-time responses of QCM, as well as electronic read-out monitoring of EIS, may open a new way for the direct detection of bacteria.
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Synthetic Antimicrobial Peptides Exhibit Two Different Binding Mechanisms to the Lipopolysaccharides Isolated from Pseudomonas aeruginosa and Klebsiella pneumoniae. INTERNATIONAL JOURNAL OF MEDICINAL CHEMISTRY 2014; 2014:809283. [PMID: 25610647 PMCID: PMC4295349 DOI: 10.1155/2014/809283] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/26/2014] [Accepted: 11/26/2014] [Indexed: 01/03/2023]
Abstract
Circular dichroism and 1H NMR were used to investigate the interactions of a
series of synthetic antimicrobial peptides (AMPs) with lipopolysaccharides (LPS) isolated from
Pseudomonas aeruginosa and Klebsiella pneumoniae. Previous CD studies with AMPs
containing only three Tic-Oic dipeptide units do not exhibit helical characteristics upon
interacting with small unilamellar vesicles (SUVs) consisting of LPS. Increasing the number of
Tic-Oic dipeptide units to six resulted in five analogues with CD spectra that exhibited helical
characteristics on binding to LPS SUVs. Spectroscopic and in vitro inhibitory data suggest that
there are two possible helical conformations resulting from two different AMP-LPS binding
mechanisms. Mechanism one involves a helical binding conformation where the AMP binds
LPS very strongly and is not efficiently transported across the LPS bilayer resulting in the loss of
inhibitory activity. Mechanism two involves a helical binding conformation where the AMP
binds LPS very loosely and is efficiently transported across the LPS bilayer resulting in an
increase in inhibitory activity. Mechanism three involves a nonhelical binding conformation
where the AMP binds LPS very loosely and is efficiently transported across the LPS bilayer
resulting in an increase in inhibitory activity.
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Jamasbi E, Batinovic S, Sharples RA, Sani MA, Robins-Browne RM, Wade JD, Separovic F, Hossain MA. Melittin peptides exhibit different activity on different cells and model membranes. Amino Acids 2014; 46:2759-66. [DOI: 10.1007/s00726-014-1833-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 08/26/2014] [Indexed: 11/30/2022]
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Pannuzzo M, Böckmann RA. Energetic view on membrane pore formation. Biophys J 2014; 106:1-2. [PMID: 24411229 DOI: 10.1016/j.bpj.2013.12.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 11/28/2013] [Accepted: 12/02/2013] [Indexed: 10/25/2022] Open
Affiliation(s)
- Martina Pannuzzo
- Computational Biology, Department of Biology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Rainer A Böckmann
- Computational Biology, Department of Biology, University of Erlangen-Nuremberg, Erlangen, Germany.
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40
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Goel M, Marsh ENG, Chen Z, Abbott NL. Comparison of the influence of humidity and D-mannitol on the organization of tetraethylene glycol-terminated self-assembled monolayers and immobilized antimicrobial peptides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7143-7151. [PMID: 24854220 DOI: 10.1021/la500926c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report the use of polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS) to characterize the effects of relative humidity (RH) and d-mannitol on the conformations of tetraethylene glycol (EG4)-terminated self-assembled monolayers (SAMs) and immobilized antimicrobial peptides (Cecropin P1 and a hybrid of Cecropin A (1-8) and Melittin (1-18)). These results are used to assess the extent to which d-mannitol can substitute for water in promoting conformational states of the SAMs and oligopeptides similar to those induced by hydration. Our measurements reveal a red shift of the COC asymmetric stretching vibration of the EG4-terminated SAMs with increasing humidity, consistent with a transition from a mixed all-trans/helical (7/2 helix) conformation at 0% RH to a predominantly helical conformation at 90% RH. Significantly, under dry conditions, a thin (2 nm in thickness) overlayer of d-mannitol generated the COC spectroscopic signature of the EG4-terminated SAM measured at high humidity. Comparisons of the effects of humidity and d-mannitol on the secondary structure of the two oligopeptides also revealed both to cause the amide I peak positions, which were measured in dry air (and without d-mannitol) to correspond to α-helical conformations, to undergo red-shifts. The magnitudes of the red-shifts, however, were more pronounced for dry d-mannitol than for high RH, with Cecropin P1 and the hybrid peptide exhibiting amide I peak positions under d-mannitol consistent with bulk aqueous solution secondary structures (random and β-sheet, respectively). These results are discussed in the context of prior reports of the tendency of d-mannitol to form glassy states in the absence of water. Overall, the results presented in this paper support the hypothesis that d-mannitol can substitute, in at least some ways, for the influence of water on the conformational states of biologically relevant molecules at interfaces. The results provide guidance for the design of interfaces for water-free biologics.
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Affiliation(s)
- Mohit Goel
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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41
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Chai H, Allen WE, Hicks RP. Spectroscopic investigations of the binding mechanisms between antimicrobial peptides and membrane models of Pseudomonas aeruginosa and Klebsiella pneumoniae. Bioorg Med Chem 2014; 22:4210-22. [PMID: 24931276 DOI: 10.1016/j.bmc.2014.05.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 05/10/2014] [Accepted: 05/18/2014] [Indexed: 10/25/2022]
Abstract
CD spectroscopy was used to investigate the interactions of a series of synthetic AMPs with LPS isolated from Pseudomonas aeruginosa and Klebsiella pneumoniae, as well as with various phospholipids to better approximate the chemical composition of the membranes of these two strains of Gram-negative bacteria. This investigation was conducted in order to probe how the contributions of key physicochemical properties of an AMP vary in different regions of the membranes of these two bacteria. The conclusions from this study are as follows. (1) The binding interactions between the AMP and the membranes are defined by the complementarity of delocalization of positive charge density of the basic amino side chains (i.e., electrostatics), molecular flexibility of the peptide backbone, and overall hydrophobicity. (2) The binding interactions of these AMPs to LPS seem to be predominantly with the lipid A region of the LPS. (3) Incorporation of phospholipids into the LPS containing SUVs resulted in dramatic changes in the conformational equilibrium of the bound AMPs. (4) For the LPS-phospholipid models of Pseudomonas aeruginosa, delocalization of the side chain positive charge plays a major role in determining the number of conformers that contribute to the binding conformational equilibrium. This relationship was not observed for the models of the outer and inner membranes of Klebsiella pneumoniae.
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Affiliation(s)
- Hanbo Chai
- Department of Chemistry, East Carolina University, Science and Technology Building, Greenville, NC 27858, United States
| | - William E Allen
- Department of Chemistry, East Carolina University, Science and Technology Building, Greenville, NC 27858, United States
| | - Rickey P Hicks
- Department of Chemistry, East Carolina University, Science and Technology Building, Greenville, NC 27858, United States.
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42
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Park D, Jung JW, Lee MO, Lee SY, Kim B, Jin HJ, Kim J, Ahn YJ, Lee KW, Song YS, Hong S, Womack JE, Kwon HW. Functional characterization of naturally occurring melittin peptide isoforms in two honey bee species, Apis mellifera and Apis cerana. Peptides 2014; 53:185-93. [PMID: 24512991 DOI: 10.1016/j.peptides.2014.01.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 12/21/2022]
Abstract
Insect-derived antimicrobial peptides (AMPs) have diverse effects on antimicrobial properties and pharmacological activities such as anti-inflammation and anticancer properties. Naturally occurring genetic polymorphism have a direct and/or indirect influence on pharmacological effect of AMPs, therefore information on single nucleotide polymorphism (SNP) occurring in natural AMPs provides an important clue to therapeutic applications. Here we identified nucleotide polymorphisms in melittin gene of honey bee populations, which is one of the potent AMP in bee venoms. We found that the novel SNP of melittin gene exists in these two honey bee species, Apis mellifera and Apis cerana. Nine polymorphisms were identified within the coding region of the melittin gene, of which one polymorphism that resulted in serine (Ser) to asparagine (Asp) substitution that can potentially effect on biological activities of melittin peptide. Serine-substituted melittin (Mel-S) showed more cytotoxic effect than asparagine-substituted melittin (Mel-N) against E. coli. Also, Mel-N and Mel-S had different inhibitory effects on the production of inflammatory factors such as IL-6 and TNF-α in BV-2 cells. Moreover, Mel-S showed stronger cytotoxic activities than Mel-N peptide against two human ovarian cancer cell lines. Using carbon nanotube-based transistor, we here characterized that Mel-S interacted with small unilamellar liposomes more strongly than Mel-N. Taken together, our present study demonstrates that there exist different characteristics of the gene frequency and the biological activities of the melittin peptide in two honey bee species, Apis mellifera and A. cerana.
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Affiliation(s)
- Doori Park
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Je Won Jung
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Mi Ok Lee
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, United States
| | - Si Young Lee
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Boyun Kim
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Hye Jun Jin
- Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea
| | - Jiyoung Kim
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Young-Joon Ahn
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Ki Won Lee
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Yong Sang Song
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Seunghun Hong
- Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea
| | - James E Womack
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, United States
| | - Hyung Wook Kwon
- WCU Biomodulation Major, Department of Agricultural Biotechnology, College of Agriculture & Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
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43
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Li Y, Afrasiabi R, Fathi F, Wang N, Xiang C, Love R, She Z, Kraatz HB. Impedance based detection of pathogenic E. coli O157:H7 using a ferrocene-antimicrobial peptide modified biosensor. Biosens Bioelectron 2014; 58:193-9. [PMID: 24637168 DOI: 10.1016/j.bios.2014.02.045] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 02/14/2014] [Accepted: 02/17/2014] [Indexed: 01/20/2023]
Abstract
Escherichia coli O157:H7 can cause life-threatening gastrointestinal diseases and has been a severe public health problem worldwide in recent years. A novel biosensor for the detection of E. coli O157:H7 is described here using a film composed of ferrocene-peptide conjugates, in which the antimicrobial peptide magainin I has been incorporated as the biorecognition element. Electrochemical impedance spectroscopy was employed to investigate the surface characteristics of the newly developed biosensor and to monitor the interactions between the peptide film and the pathogenic bacteria. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were employed to confirm the immobilization of ferrocene-conjugate onto the gold surface. Non-pathogenic E. coli K12, Staphylococcus epidermidis and Bacillus subtilis were used in this study to evaluate the selectivity of the proposed biosensor. The results have shown the order of the preferential selectivity of the method is E. coli O157:H7>non-pathogenic E. coli>gram positive species. The detection of E. coli O157:H7 with a sensitivity of 10(3)cfu/mL is enabled by the biosensor. The experimental conditions have been optimized and the plot of changes of charge transfer resistance (ΔRCT) and the logarithm of the cell concentration of E. coli O157:H7 shows a linear correlation in the range of 10(3)-10(7)cfu/mL with a correlation coefficient of 0.983.
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Affiliation(s)
- Yongxin Li
- Department of Sanitary Chemistry, Public Health School, West China Medical Center, Sichuan University, Chengdu 610044, PR China; Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada
| | - Rouzbeh Afrasiabi
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada
| | - Farkhondeh Fathi
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada
| | - Nan Wang
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada
| | - Cuili Xiang
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada; Department of Material Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, PR China
| | - Ryan Love
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada
| | - Zhe She
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada
| | - Heinz-Bernhard Kraatz
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada.
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44
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Bacteriocin AS-48 binding to model membranes and pore formation as revealed by coarse-grained simulations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2524-31. [DOI: 10.1016/j.bbamem.2013.05.036] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 05/24/2013] [Accepted: 05/31/2013] [Indexed: 02/05/2023]
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45
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Sanders MR, Clifton LA, Neylon C, Frazier RA, Green RJ. Selected wheat seed defense proteins exhibit competitive binding to model microbial lipid interfaces. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:6890-6900. [PMID: 23767912 DOI: 10.1021/jf401336a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Puroindolines (Pins) and purothionins (Pths) are basic, amphiphilic, cysteine-rich wheat proteins that play a role in plant defense against microbial pathogens. This study examined the co-adsorption and sequential addition of Pins (Pin-a, Pin-b, and a mutant form of Pin-b with Trp-44 to Arg-44 substitution) and β-purothionin (β-Pth) model anionic lipid layers using a combination of surface pressure measurements, external reflection FTIR spectroscopy, and neutron reflectometry. Results highlighted differences in the protein binding mechanisms and in the competitive binding and penetration of lipid layers between respective Pins and β-Pth. Pin-a formed a blanket-like layer of protein below the lipid surface that resulted in the reduction or inhibition of β-Pth penetration of the lipid layer. Wild-type Pin-b participated in co-operative binding with β-Pth, whereas the mutant Pin-b did not bind to the lipid layer in the presence of β-Pth. The results provide further insight into the role of hydrophobic and cationic amino acid residues in antimicrobial activity.
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Affiliation(s)
- Michael R Sanders
- Reading School of Pharmacy, University of Reading, Whiteknights, Reading, United Kingdom
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46
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Common mechanism unites membrane poration by amyloid and antimicrobial peptides. Proc Natl Acad Sci U S A 2013; 110:6382-7. [PMID: 23576726 DOI: 10.1073/pnas.1219059110] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Poration of bacterial membranes by antimicrobial peptides such as magainin 2 is a significant activity performed by innate immune systems. Pore formation by soluble forms of amyloid proteins such as islet amyloid polypeptide (IAPP) is implicated in cell death in amyloidoses. Similarities in structure and poration activity of these two systems suggest a commonality of mechanism. Here, we investigate and compare the mechanisms by which these peptides induce membrane leakage and bacterial cell death through the measurement of liposome leakage kinetics and bacterial growth inhibition. For both systems, leakage occurs through the nucleation-dependent formation of stable membrane pores. Remarkably, we observe IAPP and magainin 2 to be fully cross-cooperative in the induction of leakage and inhibition of bacterial growth. The effects are dramatic, with mixtures of these peptides showing activities >100-fold greater than simple sums of the activities of individual peptides. Direct protein-protein interactions cannot be the origin of cooperativity, as IAPP and its enantiomer D-IAPP are equally cross-cooperative. We conclude that IAPP and magainin 2 induce membrane leakage and cytotoxicity through a shared, cross-cooperative, tension-induced poration mechanism.
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47
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Clifton LA, Sanders M, Kinane C, Arnold T, Edler KJ, Neylon C, Green RJ, Frazier RA. The role of protein hydrophobicity in thionin-phospholipid interactions: a comparison of α1 and α2-purothionin adsorbed anionic phospholipid monolayers. Phys Chem Chem Phys 2013; 14:13569-79. [PMID: 22955734 DOI: 10.1039/c2cp42029e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The plant defence proteins α1- and α2-purothionin (Pth) are type 1 thionins from common wheat (Triticum aestivum). These highly homologous proteins possess characteristics common amongst antimicrobial peptides and proteins, that is, cationic charge, amphiphilicity and hydrophobicity. Both α1- and α2-Pth possess the same net charge, but differ in relative hydrophobicity as determined by C18 reversed phase HPLC. Brewster angle microscopy, X-ray and neutron reflectometry, external reflection FTIR and associated surface pressure measurements demonstrated that α1 and α2-Pth interact strongly with condensed phase 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DPPG) monolayers at the air/liquid interface. Both thionins disrupted the in-plane structure of the anionic phospholipid monolayers, removing lipid during this process and both penetrated the lipid monolayer in addition to adsorbing as a single protein layer to the lipid head-group. However, analysis of the interfacial structures revealed that the α2-Pth showed faster disruption of the lipid film and removed more phospholipid (12%) from the interface than α1-Pth. Correlating the protein properties and lipid binding activity suggests that hydrophobicity plays a key role in the membrane lipid removal activity of thionins.
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Affiliation(s)
- Luke A Clifton
- ISIS Spallation Neutron Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, UK.
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Abstract
Studying the structure of protein-lipid complexes, be they in vesicles, planar bilayers, monolayers, or nanodiscs, poses two particular challenges. Firstly such complexes are often dynamic. Secondly we need to resolve the lipid and protein structures within the complex. Neutron scattering is well placed to help in both respects since it deals with molecules in large, complex, dynamic structures and can easily differentiate between different molecular species. This comes from the great penetrating power of neutrons and their sensitivity to the difference between hydrogen (H) and deuterium (D). Both membrane proteins and lipids can be produced with varying degrees of deuteration, thus allowing us to dissect complexes with great accuracy. Two main scattering techniques are immediately applicable to the study of protein-lipid interactions. Neutron reflection exploits the constructive interference, which occurs when neutrons are reflected from different points in a layer. An everyday example is the rainbow of colors reflected from an oil film on water, which result from varying film thickness and the angle of reflection. Neutrons because of their short wavelengths (4-15 Å) and H/D sensitivity can, in reflectometry mode, provide accurate cross sections of lipid monolayers and bilayers. Small-angle neutron scattering (SANS) can resolve the structures of protein-lipid complexes if they are present as homogeneous dispersions. This is easiest with detergent micelles, but increasingly methods are being developed whereby vesicles, nanodiscs, etc., can be resolved. Again the ability to deuterate proteins and lipids enables SANS to resolve the inner structure of big, dynamic, lipid-protein complexes. The recent introduction of advanced neutron beam lines means that the technique is now within the grasp of a broad cross section of researchers.
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Ivanov IE, Morrison AE, Cobb JE, Fahey CA, Camesano TA. Creating antibacterial surfaces with the peptide chrysophsin-1. ACS APPLIED MATERIALS & INTERFACES 2012; 4:5891-5897. [PMID: 23043421 DOI: 10.1021/am301530a] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Immobilization of antimicrobial peptides (AMPs) holds potential for creating surfaces with bactericidal properties. In order to successfully incorporate AMPs into desired materials, increased fundamental understanding of the relationship between AMP immobilization and the efficacy of bound peptides as antibacterial agents is required. In this study, we characterize the relationship between surface binding of the AMP and subsequent ability of the peptide to kill bacteria. Surface immobilization of the AMP chrysophsin-1 (CHY1) via a flexible linker is studied in real-time, using a quartz crystal microbalance with dissipation monitoring (QCM-D). Depending on whether the AMP is physically adsorbed to the surface or attached covalently via a zero-length or flexible cross-linker, changes could be observed in AMP orientation, surface density, flexibility, and activity against bacteria. Covalent surface binding of CHY1 led to the formation of solvated monolayers of vertically positioned peptide molecules, while the physical adsorption of CHY1 led to the deposition of rigid monolayers of horizontally positioned peptide molecules on the sensor surface. Covalently bound peptides were not removed by extensive washing and did not leach from the surface. Zero-length immobilization of the peptide decreased its ability to kill E. coli to 34% ± 7% of added bacteria, while binding via a flexible linker resulted in 82% ± 11% of bacteria being killed by the AMP.
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Affiliation(s)
- Ivan E Ivanov
- Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA
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50
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Clifton LA, Johnson CL, Solovyova AS, Callow P, Weiss KL, Ridley H, Le Brun AP, Kinane CJ, Webster JRP, Holt SA, Lakey JH. Low resolution structure and dynamics of a colicin-receptor complex determined by neutron scattering. J Biol Chem 2011; 287:337-346. [PMID: 22081604 PMCID: PMC3249085 DOI: 10.1074/jbc.m111.302901] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Proteins that translocate across cell membranes need to overcome a significant hydrophobic barrier. This is usually accomplished via specialized protein complexes, which provide a polar transmembrane pore. Exceptions to this include bacterial toxins, which insert into and cross the lipid bilayer itself. We are studying the mechanism by which large antibacterial proteins enter Escherichia coli via specific outer membrane proteins. Here we describe the use of neutron scattering to investigate the interaction of colicin N with its outer membrane receptor protein OmpF. The positions of lipids, colicin N, and OmpF were separately resolved within complex structures by the use of selective deuteration. Neutron reflectivity showed, in real time, that OmpF mediates the insertion of colicin N into lipid monolayers. This data were complemented by Brewster Angle Microscopy images, which showed a lateral association of OmpF in the presence of colicin N. Small angle neutron scattering experiments then defined the three-dimensional structure of the colicin N-OmpF complex. This revealed that colicin N unfolds and binds to the OmpF-lipid interface. The implications of this unfolding step for colicin translocation across membranes are discussed.
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Affiliation(s)
- Luke A Clifton
- ISIS Spallation Neutron Source, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Christopher L Johnson
- Institute for Cell and Molecular Biosciences, The Medical School, University of Newcastle, Framlington Place, Newcastle-upon-Tyne NE2 4HH, United Kingdom
| | - Alexandra S Solovyova
- Institute for Cell and Molecular Biosciences, The Medical School, University of Newcastle, Framlington Place, Newcastle-upon-Tyne NE2 4HH, United Kingdom
| | - Phil Callow
- Partnership for Structural Biology, Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble, France
| | - Kevin L Weiss
- Center for Structural Molecular Biology, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - Helen Ridley
- Institute for Cell and Molecular Biosciences, The Medical School, University of Newcastle, Framlington Place, Newcastle-upon-Tyne NE2 4HH, United Kingdom
| | - Anton P Le Brun
- Institute for Cell and Molecular Biosciences, The Medical School, University of Newcastle, Framlington Place, Newcastle-upon-Tyne NE2 4HH, United Kingdom
| | - Christian J Kinane
- ISIS Spallation Neutron Source, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - John R P Webster
- ISIS Spallation Neutron Source, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Stephen A Holt
- ISIS Spallation Neutron Source, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Jeremy H Lakey
- Institute for Cell and Molecular Biosciences, The Medical School, University of Newcastle, Framlington Place, Newcastle-upon-Tyne NE2 4HH, United Kingdom.
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