1
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Sun L, Hristova K, Bondar AN, Wimley WC. Structural Determinants of Peptide Nanopore Formation. ACS NANO 2024; 18:15831-15844. [PMID: 38844421 PMCID: PMC11191747 DOI: 10.1021/acsnano.4c02824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/15/2024] [Accepted: 05/23/2024] [Indexed: 06/19/2024]
Abstract
We have evolved the nanopore-forming macrolittin peptides from the bee venom peptide melittin using successive generations of synthetic molecular evolution. Despite their sequence similarity to the broadly membrane permeabilizing cytolytic melittin, the macrolittins have potent membrane selectivity. They form nanopores in synthetic bilayers made from 1-palmitoyl, 2-oleoyl-phosphatidylcholine (POPC) at extremely low peptide concentrations and yet have essentially no cytolytic activity against any cell membrane, even at high concentration. Here, we explore the structural determinants of macrolittin nanopore stability in POPC bilayers using atomistic molecular dynamics simulations and experiments on macrolittins and single-site variants. Simulations of macrolittin nanopores in POPC bilayers show that they are stabilized by an extensive, cooperative hydrogen bond network comprised of the many charged and polar side chains interacting with each other via bridges of water molecules and lipid headgroups. Lipid molecules with unusual conformations participate in the H-bond network and are an integral part of the nanopore structure. To explore the role of this H-bond network on membrane selectivity, we swapped three critical polar residues with the nonpolar residues found in melittin. All variants have potency, membrane selectivity, and cytotoxicity that were intermediate between a cytotoxic melittin variant called MelP5 and the macrolittins. Simulations showed that the variants had less organized H-bond networks of waters and lipids with unusual structures. The membrane-spanning, cooperative H-bond network is a critical determinant of macrolittin nanopore stability and membrane selectivity. The results described here will help guide the future design and optimization of peptide nanopore-based applications.
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Affiliation(s)
- Leisheng Sun
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Kalina Hristova
- Department
of Materials Science and Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Ana-Nicoleta Bondar
- Faculty
of Physics, University of Bucharest, Atomiştilor 405, Măgurele 077125, Romania
- Forschungszentrum
Jülich, Institute of Computational
Biomedicine, IAS-5/INM-9,
Wilhelm-Johnen Straße, 5428 Jülich, Germany
| | - William C. Wimley
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
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2
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Mitra S, Chandersekhar B, Li Y, Coopershlyak M, Mahoney ME, Evans B, Koenig R, Hall SCL, Klösgen B, Heinrich F, Deslouches B, Tristram-Nagle S. Novel non-helical antimicrobial peptides insert into and fuse lipid model membranes. SOFT MATTER 2024; 20:4088-4101. [PMID: 38712559 PMCID: PMC11109824 DOI: 10.1039/d4sm00220b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 04/26/2024] [Indexed: 05/08/2024]
Abstract
This research addresses the growing menace of antibiotic resistance by exploring antimicrobial peptides (AMPs) as alternatives to conventional antibiotics. Specifically, we investigate two linear amphipathic AMPs, LE-53 (12-mer) and LE-55 (16-mer), finding that the shorter LE-53 exhibits greater bactericidal activity against both Gram-negative (G(-)) and Gram-positive (G(+)) bacteria. Remarkably, both AMPs are non-toxic to eukaryotic cells. The heightened effectiveness of LE-53 is attributed to its increased hydrophobicity (H) compared to LE-55. Circular dichroism (CD) reveals that LE-53 and LE-55 both adopt β-sheet and random coil structures in lipid model membranes (LMMs) mimicking G(-) and G(+) bacteria, so secondary structure is not the cause of the potency difference. X-ray diffuse scattering (XDS) reveals increased lipid chain order in LE-53, a potential key distinction. Additionally, XDS study uncovers a significant link between LE-53's upper hydrocarbon location in G(-) and G(+) LMMs and its efficacy. Neutron reflectometry (NR) confirms the AMP locations determined using XDS. Solution small angle X-ray scattering (SAXS) demonstrates LE-53's ability to induce vesicle fusion in bacterial LMMs without affecting eukaryotic LMMs, offering a promising strategy to combat antibiotic-resistant strains while preserving human cell integrity, whereas LE-55 has a smaller ability to induce fusion.
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Affiliation(s)
- Saheli Mitra
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Bhairavi Chandersekhar
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Yunshu Li
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Mark Coopershlyak
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Margot E Mahoney
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Brandt Evans
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Rachel Koenig
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Stephen C L Hall
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, OX11 0QX, UK
| | - Beate Klösgen
- University of Southern Denmark, Dept. Physics, Chemistry & Pharmacy, PhyLife, Campusvej 55, Odense M5230, Denmark
| | - Frank Heinrich
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Berthony Deslouches
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Stephanie Tristram-Nagle
- Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
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3
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Iversen A, Utterström J, Selegård R, Aili D. Enzymatically Triggered Peptide-Lipid Conjugation of Designed Membrane Active Peptides for Controlled Liposomal Release. ACS OMEGA 2024; 9:19613-19619. [PMID: 38708287 PMCID: PMC11064179 DOI: 10.1021/acsomega.4c01387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 03/15/2024] [Accepted: 03/27/2024] [Indexed: 05/07/2024]
Abstract
Possibilities for controlling the release of pharmaceuticals from liposomal drug delivery systems can enhance their efficacy and reduce their side effects. Membrane-active peptides (MAPs) can be tailored to promote liposomal release when conjugated to lipid head groups using thiol-maleimide chemistry. However, the rapid oxidation of thiols hampers the optimization of such conjugation-dependent release strategies. Here, we demonstrate a de novo designed MAP modified with an enzyme-labile Cys-protection group (phenylacetamidomethyl (Phacm)) that prevents oxidation and facilitates in situ peptide lipidation. Before deprotection, the peptide lacks a defined secondary structure and does not interact with maleimide-functionalized vesicles. After deprotection of Cys using penicillin G acylase (PGA), the peptide adopts an α-helical conformation and triggers rapid release of vesicle content. Both the peptide and PGA concentrations significantly influence the conjugation process and, consequently, the release kinetics. At a PGA concentration of 5 μM the conjugation and release kinetics closely mirror those of fully reduced, unprotected peptides. We anticipate that these findings will enable further refinement of MAP conjugation and release processes, facilitating the development of sophisticated bioresponsive MAP-based liposomal drug delivery systems.
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Affiliation(s)
- Alexandra Iversen
- Laboratory of Molecular Materials,
Division of Biophysics and Bioengineering, Linköping University, Linköping 581 83, Sweden
| | - Johanna Utterström
- Laboratory of Molecular Materials,
Division of Biophysics and Bioengineering, Linköping University, Linköping 581 83, Sweden
| | - Robert Selegård
- Laboratory of Molecular Materials,
Division of Biophysics and Bioengineering, Linköping University, Linköping 581 83, Sweden
| | - Daniel Aili
- Laboratory of Molecular Materials,
Division of Biophysics and Bioengineering, Linköping University, Linköping 581 83, Sweden
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4
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Jafari Z, Sadeghi S, Dehaghi MM, Bigham A, Honarmand S, Tavasoli A, Hoseini MHM, Varma RS. Immunomodulatory activities and biomedical applications of melittin and its recent advances. Arch Pharm (Weinheim) 2024; 357:e2300569. [PMID: 38251938 DOI: 10.1002/ardp.202300569] [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: 10/06/2023] [Revised: 12/10/2023] [Accepted: 12/12/2023] [Indexed: 01/23/2024]
Abstract
Melittin (MLT), a peptide containing 26 amino acids, is a key constituent of bee venom. It comprises ∼40%-60% of the venom's dry weight and is the main pricing index for bee venom, being the causative factor of pain. The unique properties of MLT extracted from bee venom have made it a very valuable active ingredient in the pharmaceutical industry as this cationic and amphipathic peptide has propitious effects on human health in diverse biological processes. It has the ability to strongly impact the membranes of cells and display hemolytic activity with anticancer characteristics. However, the clinical application of MLT has been limited by its severe hemolytic activity, which poses a challenge for therapeutic use. By employing more efficient mechanisms, such as modifying the MLT sequence, genetic engineering, and nano-delivery systems, it is anticipated that the limitations posed by MLT can be overcome, thereby enabling its wider application in therapeutic contexts. This review has outlined recent advancements in MLT's nano-delivery systems and genetically engineered cells expressing MLT and provided an overview of where the MLTMLT's platforms are and where they will go in the future with the challenges ahead. The focus is on exploring how these approaches can overcome the limitations associated with MLT's hemolytic activity and improve its selectivity and efficacy in targeting cancer cells. These advancements hold promise for the creation of innovative and enhanced therapeutic approaches based on MLT for the treatment of cancer.
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Affiliation(s)
- Zohreh Jafari
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sahar Sadeghi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahsa Mirzarazi Dehaghi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ashkan Bigham
- Institute of Polymers, Composites and Biomaterials, National Research Council of Italy (IPCB-CNR), Naples, Italy
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Naples, Italy
| | - Shokouh Honarmand
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Afsaneh Tavasoli
- Department of Biotechnology, Faculty of Pharmacy, Alborz University of Medical Sciences, Karaj, Iran
| | - Mostafa Haji Molla Hoseini
- Medical Nanotechnology and Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Rajender S Varma
- Department of Chemistry, Centre of Excellence for Research in Sustainable Chemistry, Federal University of São Carlos, São Carlos, Brazil
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5
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Almeida PF. In Search of a Molecular View of Peptide-Lipid Interactions in Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023. [PMID: 37478368 DOI: 10.1021/acs.langmuir.3c00538] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Lipid bilayer membranes are often represented as a continuous nonpolar slab with a certain thickness bounded by two more polar interfaces. Phenomena such as peptide binding to the membrane surface, folding, insertion, translocation, and diffusion are typically interpreted on the basis of this view. In this Perspective, I argue that this membrane representation as a hydrophobic continuum solvent is not adequate to understand peptide-lipid interactions. Lipids are not small compared to membrane-active peptides: their sizes are similar. Therefore, peptide diffusion needs to be understood in terms of free volume, not classical continuum mechanics; peptide solubility or partitioning in membranes cannot be interpreted in terms of hydrophobic mismatch between membrane thickness and peptide length; peptide folding and translocation, often involving cationic peptides, can only be understood if realizing that lipids adapt to the presence of peptides and the membrane may undergo considerable lipid redistribution in the process. In all of those instances, the detailed molecular interactions between the peptide residues and the lipid components are essential to understand the mechanisms involved.
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Affiliation(s)
- Paulo F Almeida
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington, Wilmington, North Carolina 28403, United States
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6
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Beck K, Nandy J, Hoernke M. Membrane permeabilization can be crucially biased by a fusogenic lipid composition - leaky fusion caused by antimicrobial peptides in model membranes. SOFT MATTER 2023; 19:2919-2931. [PMID: 37010846 DOI: 10.1039/d2sm01691e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Induced membrane permeabilization or leakage is often taken as an indication for activity of membrane-active molecules, such as antimicrobial peptides (AMPs). The exact leakage mechanism is often unknown, but important, because certain mechanisms might actually contribute to microbial killing, while others are unselective, or potentially irrelevant in an in vivo situation. Using an antimicrobial example peptide (cR3W3), we illustrate one of the potentially misleading leakage mechanisms: leaky fusion, where leakage is coupled to membrane fusion. Like many others, we examine peptide-induced leakage in model vesicles consisting of binary mixtures of anionic and zwitterionic phospholipids. In fact, phosphatidylglycerol and phosphatidylethanolamine (PG/PE) are supposed to reflect bacterial membranes, but exhibit a high propensity for vesicle aggregation and fusion. We describe the implications of this vesicle fusion and aggregation for the reliability of model studies. The ambiguous role of the relatively fusogenic PE-lipids becomes clear as leakage decreases significantly when aggregation and fusion are prevented by sterical shielding. Furthermore, the mechanism of leakage changes if PE is exchanged for phosphatidylcholine (PC). We thus point out that the lipid composition of model membranes can be biased towards leaky fusion. This can lead to discrepancies between model studies and activity in true microbes, because leaky fusion is likely prevented by bacterial peptidoglycan layers. In conclusion, choosing the model membrane might implicate the type of effect (here leakage mechanism) that is observed. In the worst case, as with leaky fusion of PG/PE vesicles, this is not directly relevant for the intended antimicrobial application.
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Affiliation(s)
- Katharina Beck
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, Freiburg i. Br., Germany.
| | - Janina Nandy
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, Freiburg i. Br., Germany.
| | - Maria Hoernke
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, Freiburg i. Br., Germany.
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7
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Shi S, Fan H, Hoernke M. Leaky membrane fusion: an ambivalent effect induced by antimicrobial polycations. NANOSCALE ADVANCES 2022; 4:5109-5122. [PMID: 36504745 PMCID: PMC9680940 DOI: 10.1039/d2na00464j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/24/2022] [Indexed: 05/28/2023]
Abstract
Both antimicrobial peptides and their synthetic mimics are potential alternatives to classical antibiotics. They can induce several membrane perturbations including permeabilization. Especially in model studies, aggregation of vesicles by such polycations is often reported. Here, we show that unintended vesicle aggregation or indeed fusion can cause apparent leakage in model studies that is not possible in most microbes, thus potentially leading to misinterpretations. The interactions of a highly charged and highly selective membrane-active polycation with negatively charged phosphatidylethanolamine/phosphatidylglycerol (PE/PG) vesicles are studied by a combination of biophysical methods. At low polycation concentrations, apparent vesicle aggregation was found to involve exchange of lipids. Upon neutralization of the negatively charged vesicles by the polycation, full fusion and leakage occurred and leaky fusion is suspected. To elucidate the interplay of leakage and fusion, we prevented membrane contacts by decorating the vesicles with PEG-chains. This inhibited fusion and also leakage activity. Leaky fusion is further corroborated by increased leakage with increasing likeliness of vesicle-vesicle contacts. Because of its similar appearance to other leakage mechanisms, leaky fusion is difficult to identify and might be overlooked and more common amongst polycationic membrane-active compounds. Regarding biological activity, leaky fusion needs to be carefully distinguished from other membrane permeabilization mechanisms, as it may be less relevant to bacteria, but potentially relevant for fungi. Furthermore, leaky fusion is an interesting effect that could help in endosomal escape for drug delivery. A comprehensive step-by-step protocol for membrane permeabilization/vesicle leakage using calcein fluorescence lifetime is provided in the ESI.
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Affiliation(s)
- Shuai Shi
- Chemistry and Pharmacy, Albert-Ludwigs-Universität 79104 Freiburg i.Br. Germany
| | - Helen Fan
- Leslie Dan Faculty of Pharmacy, University of Toronto Toronto Canada
| | - Maria Hoernke
- Chemistry and Pharmacy, Albert-Ludwigs-Universität 79104 Freiburg i.Br. Germany
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8
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Puthumadathil N, Krishnan R S, Nair GS, Mahendran KR. Assembly of alpha-helical transmembrane pores through an intermediate state. NANOSCALE 2022; 14:6507-6517. [PMID: 35420118 DOI: 10.1039/d2nr00556e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Pore-forming alpha-helical proteins are well known for their dynamic assembly mechanism and it has been challenging to delineate the pore-forming structures in membranes. Previously, attempts have been made to elucidate their assembly mechanism and there is a large gap due to complex pathways by which these membrane-active pores impart their effect. Here we demonstrate a multi-step structural assembly pathway of alpha-helical peptide pores formed by a 37 amino acid synthetic peptide, pPorU, based on the natural porin from Corynebacterium urealyticum using single-channel electrical recordings. More specifically, we report detectable intermediate states during the membrane insertion and pore formation of pPorU. The fully assembled pore exhibited unusually large stable conductance, voltage-dependent gating, and functional blockage by cyclic sugars generally applicable to a range of transmembrane pores. Furthermore, we used rationally designed mutants to understand the role of specific amino acids in the assembly of these peptide pores. Mutant peptides that differ from wild-type peptides produced noisy and unstable intermediate states and low conductance pores, demonstrating sequence specificity in the pore-formation process supported by molecular dynamics simulations. We suggest that our study contributes to understanding the mechanism of action of naturally occurring alpha-helical pore-forming proteins and should be of broad interest to build peptide-based nanopore sensors.
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Affiliation(s)
- Neethu Puthumadathil
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
- Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Smrithi Krishnan R
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
- Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Greeshma S Nair
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
| | - Kozhinjampara R Mahendran
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
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9
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Chen CH, Bepler T, Pepper K, Fu D, Lu TK. Synthetic molecular evolution of antimicrobial peptides. Curr Opin Biotechnol 2022; 75:102718. [PMID: 35395425 DOI: 10.1016/j.copbio.2022.102718] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/14/2022] [Accepted: 03/01/2022] [Indexed: 01/18/2023]
Abstract
As we learn more about how peptide structure and activity are related, we anticipate that antimicrobial peptides will be engineered to have strong potency and distinct functions and that synthetic peptides will have new biomedical applications, such as treatments for emerging infectious diseases. As a result of the enormous number of possible amino acid sequences and the low-throughput nature of antimicrobial peptide assays, computational tools for peptide design and optimization are needed for direct experimentation toward obtaining functional sequences. Recent developments in computational tools have improved peptide design, saving labor, reagents, costs, and time. At the same time, improvements in peptide synthesis and experimental platforms continue to reduce the cost and increase the throughput of peptide-drug screening. In this review, we discuss the current methods of peptide design and engineering, including in silico methods and peptide synthesis and screening, and highlight areas of potential improvement.
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Affiliation(s)
- Charles H Chen
- Synthetic Biology Center, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Tristan Bepler
- Synthetic Biology Center, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Simons Machine Learning Center, New York Structural Biology Center, New York, NY 10027, USA
| | - Karen Pepper
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Debbie Fu
- Department of Biology, Tufts University, Medford, MA 02155, USA
| | - Timothy K Lu
- Synthetic Biology Center, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, MA 02142, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02142, USA; Senti Biosciences, South San Francisco, CA 94080, USA.
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10
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Utterström J, Barriga HMG, Holme MN, Selegård R, Stevens MM, Aili D. Peptide-Folding Triggered Phase Separation and Lipid Membrane Destabilization in Cholesterol-Rich Lipid Vesicles. Bioconjug Chem 2022; 33:736-746. [PMID: 35362952 PMCID: PMC9026255 DOI: 10.1021/acs.bioconjchem.2c00115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Liposome-based drug
delivery systems are widely used to improve
drug pharmacokinetics but can suffer from slow and unspecific release
of encapsulated drugs. Membrane-active peptides, based on sequences
derived or inspired from antimicrobial peptides (AMPs), could offer
means to trigger and control the release. Cholesterol is used in most
liposomal drug delivery systems (DDS) to improve the stability of
the formulation, but the activity of AMPs on cholesterol-rich membranes
tends to be very low, complicating peptide-triggered release strategies.
Here, we show a de novo designed AMP-mimetic peptide that efficiently
triggers content release from cholesterol-containing lipid vesicles
when covalently conjugated to headgroup-functionalized lipids. Binding
to vesicles induces peptide folding and triggers a lipid phase separation,
which in the presence of cholesterol results in high local peptide
concentrations at the lipid bilayer surface and rapid content release.
We anticipate that these results will facilitate the development of
peptide-based strategies for controlling and triggering drug release
from liposomal drug delivery systems.
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Affiliation(s)
- Johanna Utterström
- Laboratory of Molecular Materials, Division of Biophysics and Bioengineering, Department of Physics, Chemistry and Biology, SE-581 83 Linköping, Sweden
| | - Hanna M G Barriga
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Margaret N Holme
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Robert Selegård
- Laboratory of Molecular Materials, Division of Biophysics and Bioengineering, Department of Physics, Chemistry and Biology, SE-581 83 Linköping, Sweden
| | - Molly M Stevens
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.,Department of Materials, Department of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K
| | - Daniel Aili
- Laboratory of Molecular Materials, Division of Biophysics and Bioengineering, Department of Physics, Chemistry and Biology, SE-581 83 Linköping, Sweden
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11
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Shi S, Markl AM, Lu Z, Liu R, Hoernke M. Interplay of Fusion, Leakage, and Electrostatic Lipid Clustering: Membrane Perturbations by a Hydrophobic Antimicrobial Polycation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:2379-2391. [PMID: 35148117 DOI: 10.1021/acs.langmuir.1c03445] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Membrane active compounds are able to induce various types of membrane perturbations. Natural or biomimetic candidates for antimicrobial treatment or drug delivery scenarios are mostly designed and tested for their ability to induce membrane permeabilization, also termed leakage. Furthermore, the interaction of these usually cationic amphiphiles with negatively charged vesicles often causes colloidal instability leading to vesicle aggregation or/and vesicle fusion. We show the interplay of these modes of membrane perturbation in mixed phosphatidyl glycerol (PG)/phosphatidyl ethanolamine (PE) by the statistical copolymer MM:CO comprising, both, charged and hydrophobic subunits. MM:CO is a representative of partially hydrophobic, highly active, but less selective antimicrobial polycations. Cryo-electron microscopy indicates vesicle fusion rather than vesicle aggregation upon the addition of MM:CO to negatively charged PG/PE (1:1) vesicles. In a combination of fluorescence-based leakage and fusion assays, there is support for membrane permeabilization and pronounced vesicle fusion activity as distinct effects. To this end, membrane fusion and aggregation were prevented by including lipids with polyethylene glycol attached to their head groups (PEG-lipids). The leakage activity of MM:CO is very similar in the absence and presence of PEG-lipids. Vesicle aggregation and fusion however are largely suppressed. This strongly suggests that MM:CO induces leakage by asymmetric packing stress because of hydrophobically driven interactions which could lead to leakage. As a further membrane perturbation effect, MM:CO causes lipid clustering in model vesicles. We address potential artifacts and misinterpretations of experiments characterizing leakage and fusion. Additional to the leakage activity, the pronounced fusogenic activity of the polymer and potentially of many other similar compounds likely has implications for antimicrobial activity and beyond.
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Affiliation(s)
- Shuai Shi
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, 79104 Freiburg i.Br., Germany
| | - Anja Madleine Markl
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, 79104 Freiburg i.Br., Germany
| | - Ziyi Lu
- State Key Laboratory of Bioreactor Engineering, Key Laboratory for Ultrafine Materials of Ministry of Education, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Research Center for Biomedical Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Runhui Liu
- State Key Laboratory of Bioreactor Engineering, Key Laboratory for Ultrafine Materials of Ministry of Education, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Research Center for Biomedical Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Maria Hoernke
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, 79104 Freiburg i.Br., Germany
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12
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Delvaux NA, Rice KG. The Reduced-Charge Melittin Analogue MelP5 Improves the Transfection of Non-Viral DNA Nanoparticles. J Pept Sci 2022; 28:e3404. [PMID: 35001445 PMCID: PMC10069327 DOI: 10.1002/psc.3404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 11/07/2022]
Abstract
Melittin is a 26 amino acid amphiphilic alpha-helical peptide derived from honeybee venom. Prior studies have incorporated melittin into non-viral delivery systems to effect endosomal escape of DNA nanoparticles and improve transfection efficiency. Recent advances have led to the development of two newer melittin analogues, MelP5 and Macrolittin 70, with improved pore formation in lipid bilayers while possessing fewer positive charges relative to natural melittin. Consequently, MelP5 and Macrolittin 70 were conjugated through a disulfide bond to a DNA binding polyacridine peptide. The resulting peptide conjugates were used to prepare DNA nanoparticles to compare their relative endosomolytic potency by transfection of HepG2 cells. Melittin and MelP5 conjugates were equally potent at mediating in vitro gene transfer, whereas PEGylation of DNA nanoparticles revealed improved transfection with MelP5 relative to melittin. The results demonstrate the ability to substitute a potent, reduced charge analogue of melittin to improve overall DNA nanoparticle biocompatibility needed for in vivo testing.
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Affiliation(s)
- Nathan A Delvaux
- Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City, IA
| | - Kevin G Rice
- Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City, IA
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Guha S, Ferrie RP, Ghimire J, Ventura CR, Wu E, Sun L, Kim SY, Wiedman GR, Hristova K, Wimley WC. Applications and evolution of melittin, the quintessential membrane active peptide. Biochem Pharmacol 2021; 193:114769. [PMID: 34543656 DOI: 10.1016/j.bcp.2021.114769] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 12/12/2022]
Abstract
Melittin, the main venom component of the European Honeybee, is a cationic linear peptide-amide of 26 amino acid residues with the sequence: GIGAVLKVLTTGLPALISWIKRKRQQ-NH2. Melittin binds to lipid bilayer membranes, folds into amphipathic α-helical secondary structure and disrupts the permeability barrier. Since melittin was first described, a remarkable array of activities and potential applications in biology and medicine have been described. Melittin is also a favorite model system for biophysicists to study the structure, folding and function of peptides and proteins in membranes. Melittin has also been used as a template for the evolution of new activities in membranes. Here we overview the rich history of scientific research into the many activities of melittin and outline exciting future applications.
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Affiliation(s)
- Shantanu Guha
- University of Texas Health Science Center at Houston, Department of Microbiology and Molecular Genetics, Houston, TX, USA
| | - Ryan P Ferrie
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Jenisha Ghimire
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Cristina R Ventura
- Seton Hall University, Department of Chemistry and Biochemistry, South Orange, NJ, USA
| | - Eric Wu
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Leisheng Sun
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Sarah Y Kim
- Duke University, Department of Biomedical Engineering, Durham, NC, USA
| | - Gregory R Wiedman
- Seton Hall University, Department of Chemistry and Biochemistry, South Orange, NJ, USA
| | - Kalina Hristova
- Johns Hopkins University, Department of Materials Science and Engineering, Baltimore, MD, USA.
| | - Wimley C Wimley
- University of Texas Health Science Center at Houston, Department of Microbiology and Molecular Genetics, Houston, TX, USA.
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