1
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Răileanu M, Bacalum M. Cancer Wars: Revenge of the AMPs (Antimicrobial Peptides), a New Strategy against Colorectal Cancer. Toxins (Basel) 2023; 15:459. [PMID: 37505728 PMCID: PMC10467133 DOI: 10.3390/toxins15070459] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/08/2023] [Accepted: 07/12/2023] [Indexed: 07/29/2023] Open
Abstract
Cancer is a multifaceted health issue that affects people globally and it is considered one of the leading causes of death with a high percentage of victims worldwide. In recent years, research studies have uncovered great advances in cancer diagnosis and treatment. But, there are still major drawbacks of the conventional therapies used including severe side effects, toxicity, and drug resistance. That is why it is critical to develop new drugs with advantages like low cytotoxicity and no treatment resistance to the cancer cells. Antimicrobial peptides (AMPs) have recently attracted attention as a novel therapeutic strategy for the treatment of various cancers, targeting tumor cells with less toxicity to normal tissues. The aim of the study was to discover alternate treatments that do not lead to cancer resistance and have fewer side effects. Here, we report the effects induced by several AMPs, Melittin, Cecropin A, and a Cecropin A-Melittin hybrid, against two human colorectal cancer-derived spheroids. To study the effects of the peptides, cell viability was investigated using MTT, LDH, and ATP assays. Furthermore, cellular senescence and cell cycle were investigated. We found that using different concentrations of these peptides affected the spheroids, their structure being highly compromised by reducing cell viability, and the increase in ATP and LDH levels. Also, the cells are arrested in the G2/M phase leading to an increase in senescent cells. We show that Melittin and the hybrid are most effective against the 3D colorectal cancer cells compared to Cecropin A.
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Affiliation(s)
| | - Mihaela Bacalum
- Department of Life and Environmental Physics, Horia Hulubei National Institute of Physics and Nuclear Engineering, 30 Reactorului Street, RO-077125 Magurele, Romania;
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2
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Matsuzaki K. Elucidation of Complex Dynamic Intermolecular Interactions in Membranes. Chem Pharm Bull (Tokyo) 2022; 70:1-9. [PMID: 34980725 DOI: 10.1248/cpb.c21-00815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Biomembranes composed of various proteins and lipids play important roles in cellular functions, such as signal transduction and substance transport. In addition, some bioactive peptides and pathogenic proteins target membrane proteins and lipids to exert their effects. Therefore, an understanding of dynamic and complex intermolecular interactions among these membrane constituents is needed to elucidate their mechanisms. This review summarizes the major research carried out in the author's laboratory on how lipids and their inhomogeneous distributions regulate the structures and functions of antimicrobial peptides and Alzheimer's amyloid β-protein. Also, how to detect transmembrane helix-helix and membrane protein-protein interactions and how they are modulated by lipids are discussed.
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3
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Kwun MS, Lee DG. Apoptosis-like death-inducing property of tachyplesin I in Escherichia coli. J Basic Microbiol 2021; 61:795-807. [PMID: 34337763 DOI: 10.1002/jobm.202100133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/19/2021] [Accepted: 07/04/2021] [Indexed: 11/10/2022]
Abstract
Antimicrobial peptide (AMP) derived from the horseshoe crab, tachyplesin I (KWCFRVCYRGICYRRCR-NH2 ), displayed the apparent antimicrobial activity with low cytotoxicity, suggesting its efficacy as an attractive agent but still lacks the understandings regarding its mechanism(s). Hence, the study focused on investigating the antibacterial mode of action of tachyplesin I against Escherichia coli. Based on the reactive oxygen species generation displayed in several antimicrobial effects, the detection of superoxide anion and nitric oxide were verified after tachyplesin I treatment. Substantial increment of two molecules was followed by the imbalance in intracellular ion concentration, noticeably magnesium and calcium. The series of stages led to hydroxyl radical generation with reduced glutathione, followed by damage in DNA due to oxidative stress. Eventually, the apoptosis-like death in E. coli was monitored in DNA fragmentation-dependent manner due to the tachyplesin I treatment, verified by membrane depolarization, caspase-like protein activation, and phosphatidylserine exposure. Accordingly, tachyplesin I induces apoptosis-like death in E. coli, suggesting the potential of being a candidate for regulating bacterial infection.
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Affiliation(s)
- Min Seok Kwun
- School of Life Sciences, BK 21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu, Republic of Korea
| | - Dong Gun Lee
- School of Life Sciences, BK 21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu, Republic of Korea
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4
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Wu J, Chen X, Zhang J, Chen J, Wang Y, Wei T, Ma J, Li Y, Mo T, He Z, Zhang H. Tachyplesin induces apoptosis in non-small cell lung cancer cells and enhances the chemosensitivity of A549/DDP cells to cisplatin by activating Fas and necroptosis pathway. Chem Biol Drug Des 2020; 97:809-820. [PMID: 33245189 DOI: 10.1111/cbdd.13810] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 11/15/2020] [Indexed: 12/23/2022]
Abstract
Cisplatin has strong broad-spectrum anticancer activity and is one of the most effective anticancer drugs currently used. The clinical application of cisplatin has led to the resistance of cancer cells to cisplatin. Tachyplesin is an active, natural marine peptide with antitumour activity. In the present study, we investigated whether tachyplesin can be used in non-small cell lung cancer (NSCLC) A549 and H460 cells as well as the cisplatin-resistant human A549/DDP NSCLC cell line. The results revealed that tachyplesin treatment significantly inhibited proliferation and induced apoptosis in A549 and H460 cells and the combination of tachyplesin and cisplatin significantly suppressed migration and improved sensitivity to cisplatin in A549/DDP cells. Further mechanistic examination revealed that tachyplesin induced apoptosis in A549/DDP cells by increasing Fas, FasL and p-RIPK1 levels. These results indicated that tachyplesin induces lung cancer death by activating the Fas, mitochondrial and necroptosis pathways. Tachyplesin could be developed as a candidate drug for cisplatin-resistant NSCLC.
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Affiliation(s)
- Jun Wu
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China
| | - Xi Chen
- Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China.,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Jiaxi Zhang
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Jianming Chen
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yajun Wang
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China
| | - Ting Wei
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China.,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Jinyao Ma
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yuanqi Li
- Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China.,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Ting Mo
- Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China.,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China
| | - Zhan He
- Respiratory and critical care medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Haitao Zhang
- Department of Biochemistry and Molecular Biology, Guangdong Medical University, Zhanjiang, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, China.,Peptide and Protein Research and Application Key Laboratory of Guangdong Medical University, Zhanjiang, China.,The Fourth People's Hospital of Foshan, Foshan, China
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5
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Remington JM, Liao C, Sharafi M, Marie ES, Ferrell JB, Hondal R, Wargo MJ, Schneebeli ST, Li J. Aggregation State of Synergistic Antimicrobial Peptides. J Phys Chem Lett 2020; 11:9501-9506. [PMID: 33108730 PMCID: PMC8299379 DOI: 10.1021/acs.jpclett.0c02094] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
By integrating various simulation and experimental techniques, we discovered that antimicrobial peptides (AMPs) may achieve synergy at an optimal concentration and ratio, which can be caused by aggregation of the synergistic peptides. On multiple time and length scales, our studies obtain novel evidence of how peptide coaggregation in solution can affect the disruption of membranes by synergistic AMPs. Our findings provide crucial details about the complex molecular origins of AMP synergy, which will help guide the future development of synergistic AMPs as well as applications of anti-infective peptide cocktail therapies.
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Affiliation(s)
| | - Chenyi Liao
- Department of Chemistry, University of Vermont, Burlington, VT 05405
| | - Mona Sharafi
- Department of Chemistry, University of Vermont, Burlington, VT 05405
| | - Emma Ste. Marie
- Department of Chemistry, University of Vermont, Burlington, VT 05405
- Department of Biochemistry, University of Vermont, Burlington, VT 05405
| | | | - Robert Hondal
- Department of Chemistry, University of Vermont, Burlington, VT 05405
- Department of Biochemistry, University of Vermont, Burlington, VT 05405
| | - Matthew J. Wargo
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT 05405
| | | | - Jianing Li
- Department of Chemistry, University of Vermont, Burlington, VT 05405
- Corresponding Author Jianing Li ()
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6
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Study of the Interaction of a Novel Semi-Synthetic Peptide with Model Lipid Membranes. MEMBRANES 2020; 10:membranes10100294. [PMID: 33086635 PMCID: PMC7603383 DOI: 10.3390/membranes10100294] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/14/2020] [Accepted: 10/16/2020] [Indexed: 12/31/2022]
Abstract
Most linear peptides directly interact with membranes, but the mechanisms of interaction are far from being completely understood. Here, we present an investigation of the membrane interactions of a designed peptide containing a non-natural, synthetic amino acid. We selected a nonapeptide that is reported to interact with phospholipid membranes, ALYLAIRKR, abbreviated as ALY. We designed a modified peptide (azoALY) by substituting the tyrosine residue of ALY with an antimicrobial azobenzene-bearing amino acid. Both of the peptides were examined for their ability to interact with model membranes, assessing the penetration of phospholipid monolayers, and leakage across the bilayer of large unilamellar vesicles (LUVs) and giant unilamellar vesicles (GUVs). The latter was performed in a microfluidic device in order to study the kinetics of leakage of entrapped calcein from the vesicles at the single vesicle level. Both types of vesicles were prepared from a 9:1 (mol/mol) mixture of POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) and POPG (1-palmitoyl-2-oleoyl-sn-glycero-3-phospho(1′-rac-glycerol). Calcein leakage from the vesicles was more pronounced at a low concentration in the case of azoALY than for ALY. Increased vesicle membrane disturbance in the presence of azoALY was also evident from an enzymatic assay with LUVs and entrapped horseradish peroxidase. Molecular dynamics simulations of ALY and azoALY in an anionic POPC/POPG model bilayer showed that ALY peptide only interacts with the lipid head groups. In contrast, azoALY penetrates the hydrophobic core of the bilayers causing a stronger membrane perturbation as compared to ALY, in qualitative agreement with the experimental results from the leakage assays.
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7
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Juliano SA, Serafim LF, Duay SS, Heredia Chavez M, Sharma G, Rooney M, Comert F, Pierce S, Radulescu A, Cotten ML, Mihailescu M, May ER, Greenwood AI, Prabhakar R, Angeles-Boza AM. A Potent Host Defense Peptide Triggers DNA Damage and Is Active against Multidrug-Resistant Gram-Negative Pathogens. ACS Infect Dis 2020; 6:1250-1263. [PMID: 32251582 DOI: 10.1021/acsinfecdis.0c00051] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Gram-negative bacteria are some of the biggest threats to public health due to a large prevalence of antibiotic resistance. The difficulty in treating bacterial infections, stemming from their double membrane structure combined with efflux pumps in the outer membrane, has resulted in a much greater need for antimicrobials with activity against these pathogens. Tunicate host defense peptide (HDP), Clavanin A, is capable of not only inhibiting Gram-negative growth but also potentiating activity in the presence of Zn(II). Here, we provide evidence that the improvements of Clavanin A activity in the presence of Zn(II) are due to its novel mechanism of action. We employed E. coli TD172 (ΔrecA::kan) and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay to show in cellulae that DNA damage occurs upon treatment with Clavanin A. In vitro assays demonstrated that Zn(II) ions are required for the nuclease activity of the peptide. The quantum mechanics/molecular mechanics (QM/MM) calculations were used to investigate the mechanism of DNA damage. In the rate-determining step of the proposed mechanism, due to its Lewis acidity, the Zn(II) ion activates the scissile P-O bond of DNA and creates a hydroxyl nucleophile from a water molecule. A subsequent attack by this group to the electrophilic phosphorus cleaves the scissile phosphoester bond. Additionally, we utilized bacterial cytological profiling (BCP), circular dichroism (CD) spectroscopy in the presence of lipid vesicles, and surface plasmon resonance combined with electrical impedance spectroscopy in order to address the apparent discrepancies between our results and the previous studies regarding the mechanism of action of Clavanin A. Finally, our approach may lead to the identification of additional Clavanin A like HDPs and promote the development of antimicrobial peptide based therapeutics.
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Affiliation(s)
- Samuel A. Juliano
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, Connecticut 06269, United States
| | - Leonardo F. Serafim
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Searle S. Duay
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, Connecticut 06269, United States
| | - Maria Heredia Chavez
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, Connecticut 06269, United States
| | - Gaurav Sharma
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Mary Rooney
- Department of Applied Science, William and Mary, Williamsburg, Virginia 23187-8795, United States
| | - Fatih Comert
- Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, Maryland 20850, United States
| | - Scott Pierce
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, Connecticut 06269, United States
| | - Andrei Radulescu
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, Connecticut 06269, United States
| | - Myriam L. Cotten
- Department of Applied Science, William and Mary, Williamsburg, Virginia 23187-8795, United States
| | - Mihaela Mihailescu
- Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, Maryland 20850, United States
| | - Eric R. May
- Department of Molecular and Cell Biology, University of Connecticut, 91 N. Eagleville Road, Storrs, Connecticut 06269, United States
| | - Alexander I. Greenwood
- Department of Applied Science, William and Mary, Williamsburg, Virginia 23187-8795, United States
| | - Rajeev Prabhakar
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Alfredo M. Angeles-Boza
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, Connecticut 06269, United States
- Institute of Materials Science, University of Connecticut, 97 N. Eagleville Road, Storrs, Connecticut 06269, United States
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8
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Neshani A, Sedighian H, Mirhosseini SA, Ghazvini K, Zare H, Jahangiri A. Antimicrobial peptides as a promising treatment option against Acinetobacter baumannii infections. Microb Pathog 2020; 146:104238. [PMID: 32387392 DOI: 10.1016/j.micpath.2020.104238] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 04/26/2020] [Accepted: 04/27/2020] [Indexed: 12/18/2022]
Abstract
BACKGROUND With the increasing rate of antibiotic resistance in Acinetobacter, the World Health Organization introduced the carbapenem-resistant isolates in the priority pathogens list for which innovative new treatments are urgently needed. Antimicrobial peptides (AMPs) are one of the antimicrobial agents with high potential to produce new anti-Acinetobacter drugs. This review aims to summarize recent advances and compare AMPs with anti-Acinetobacter baumannii activity. METHODS Active AMPs against Acinetobacter were considered, and essential features, including structure, mechanism of action, anti-A. baumannii potent, and other prominent characteristics, were investigated and compared to each other. In this regard, the Google Scholar search engine and databases of PubMed, Scopus, and Web of Science were used. RESULTS Forty-six anti-Acinetobacter peptides were identified and classified into ten groups: Cathelicidins, Defensins, Frog AMPs, Melittin, Cecropins, Mastoparan, Histatins, Dermcidins, Tachyplesins, and computationally designed AMPs. According to the Minimum Inhibitory Concentration (MIC) reports, six peptides of Melittin, Histatin-8, Omega76, AM-CATH36, Hymenochirin, and Mastoparan have the highest anti-A. baumannii power against sensitive and antibiotic-resistant isolates. All anti-Acinetobacter peptides except Dermcidin have a net positive charge. Most of these peptides have alpha-helical structure; however, β-sheet and other structures have been observed among them. The mechanism of action of these antimicrobial agents is divided into two categories of membrane-based and intracellular target-based attack. CONCLUSION Evidence from this review indicates that AMPs would be likely among the main anti-A. baumannii drugs in the post-antibiotic era. Also, the application of computer science to increase anti-A. baumannii activity and reduce toxicity could be helpful.
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Affiliation(s)
- Alireza Neshani
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran; Department of Laboratory Sciences, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran; Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hamid Sedighian
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Seyed Ali Mirhosseini
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Kiarash Ghazvini
- Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hosna Zare
- Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Abolfazl Jahangiri
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
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9
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Vernen F, Harvey PJ, Dias SA, Veiga AS, Huang YH, Craik DJ, Lawrence N, Troeira Henriques S. Characterization of Tachyplesin Peptides and Their Cyclized Analogues to Improve Antimicrobial and Anticancer Properties. Int J Mol Sci 2019; 20:E4184. [PMID: 31455019 PMCID: PMC6747087 DOI: 10.3390/ijms20174184] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/21/2019] [Accepted: 08/21/2019] [Indexed: 02/07/2023] Open
Abstract
Tachyplesin I, II and III are host defense peptides from horseshoe crab species with antimicrobial and anticancer activities. They have an amphipathic β-hairpin structure, are highly positively-charged and differ by only one or two amino acid residues. In this study, we compared the structure and activity of the three tachyplesin peptides alongside their backbone cyclized analogues. We assessed the peptide structures using nuclear magnetic resonance (NMR) spectroscopy, then compared the activity against bacteria (both in the planktonic and biofilm forms) and a panel of cancerous cells. The importance of peptide-lipid interactions was examined using surface plasmon resonance and fluorescence spectroscopy methodologies. Our studies showed that tachyplesin peptides and their cyclic analogues were most potent against Gram-negative bacteria and melanoma cell lines, and showed a preference for binding to negatively-charged lipid membranes. Backbone cyclization did not improve potency, but improved peptide stability in human serum and reduced toxicity toward human red blood cells. Peptide-lipid binding affinity, orientation within the membrane, and ability to disrupt lipid bilayers differed between the cyclized peptide and the parent counterpart. We show that tachyplesin peptides and cyclized analogues have similarly potent antimicrobial and anticancer properties, but that backbone cyclization improves their stability and therapeutic potential.
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Affiliation(s)
- Felicitas Vernen
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Peta J Harvey
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Susana A Dias
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Ana Salomé Veiga
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Yen-Hua Huang
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David J Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Nicole Lawrence
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Sónia Troeira Henriques
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
- School of Biomedical Sciences, Faculty of Health, Institute of Health & Biomedical Innovation, Queensland University of Technology, Translational Research Institute, Brisbane, Queensland 4102, Australia.
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10
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Guha S, Ghimire J, Wu E, Wimley WC. Mechanistic Landscape of Membrane-Permeabilizing Peptides. Chem Rev 2019; 119:6040-6085. [PMID: 30624911 DOI: 10.1021/acs.chemrev.8b00520] [Citation(s) in RCA: 150] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Membrane permeabilizing peptides (MPPs) are as ubiquitous as the lipid bilayer membranes they act upon. Produced by all forms of life, most membrane permeabilizing peptides are used offensively or defensively against the membranes of other organisms. Just as nature has found many uses for them, translational scientists have worked for decades to design or optimize membrane permeabilizing peptides for applications in the laboratory and in the clinic ranging from antibacterial and antiviral therapy and prophylaxis to anticancer therapeutics and drug delivery. Here, we review the field of membrane permeabilizing peptides. We discuss the diversity of their sources and structures, the systems and methods used to measure their activities, and the behaviors that are observed. We discuss the fact that "mechanism" is not a discrete or a static entity for an MPP but rather the result of a heterogeneous and dynamic ensemble of structural states that vary in response to many different experimental conditions. This has led to an almost complete lack of discrete three-dimensional active structures among the thousands of known MPPs and a lack of useful or predictive sequence-structure-function relationship rules. Ultimately, we discuss how it may be more useful to think of membrane permeabilizing peptides mechanisms as broad regions of a mechanistic landscape rather than discrete molecular processes.
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Affiliation(s)
- Shantanu Guha
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - Jenisha Ghimire
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - Eric Wu
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - William C Wimley
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
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11
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Matsuzaki K. Membrane Permeabilization Mechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1117:9-16. [PMID: 30980350 DOI: 10.1007/978-981-13-3588-4_2] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Many antimicrobial peptides are considered to kill microbes by permeabilizing cell membranes. This chapter summarizes the driving force of peptide binding to membranes; various mechanisms of lipid bilayer permeabilization including the barrel-stave, toroidal pore, and carpet models; and modes of permeabilization of bacterial and mammalian membranes.
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Affiliation(s)
- Katsumi Matsuzaki
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan.
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12
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Liu C, Qi J, Shan B, Ma Y. Tachyplesin Causes Membrane Instability That Kills Multidrug-Resistant Bacteria by Inhibiting the 3-Ketoacyl Carrier Protein Reductase FabG. Front Microbiol 2018; 9:825. [PMID: 29765362 PMCID: PMC5938390 DOI: 10.3389/fmicb.2018.00825] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/11/2018] [Indexed: 12/19/2022] Open
Abstract
Tachyplesin is a type of cationic β-hairpin antimicrobial peptide discovered in horseshoe crab approximately 30 years ago that is well known for both its potential antimicrobial activities against multidrug-resistant bacteria and its cytotoxicity to mammalian cells. Though its physical interactions with artificial membranes have been well studied, details of its physiological mechanism of action the physiological consequences of its action remain limited. By using the DNA-binding fluorescent dye propidium iodide to monitor membrane integrity, confocal microscopy to assess the intracellular location of FITC-tagged tachyplesin, and RNA sequencing of the differentially expressed genes in four Gram-negative bacteria (Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa) treated with lethal or sublethal concentrations of tachyplesin, we found that compared with levofloxacin-treated bacteria, tachyplesin-treated bacteria showed significant effects on the pathways underlying unsaturated fatty acid biosynthesis. Notably, RNA levels of the conserved and essential 3-ketoacyl carrier protein reductase in this pathway (gene FabG) were elevated in all of the four bacteria after tachyplesin treatment. In vitro tests including surface plasmon resonance and enzyme activity assays showed that tachyplesin could bind and inhibit 3-ketoacyl carrier protein reductase, which was consistent with molecular docking prediction results. As unsaturated fatty acids are important for membrane fluidity, our results provided one possible mechanism to explain how tachyplesin kills bacteria and causes cytotoxicity by targeting membranes, which may be helpful for designing more specific and safer antibiotics based on the function of tachyplesin.
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Affiliation(s)
- Cunbao Liu
- Laboratory of Molecular Immunology, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
| | - Jialong Qi
- Laboratory of Molecular Immunology, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
| | - Bin Shan
- Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Yanbing Ma
- Laboratory of Molecular Immunology, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
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13
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Lipkin R, Pino-Angeles A, Lazaridis T. Transmembrane Pore Structures of β-Hairpin Antimicrobial Peptides by All-Atom Simulations. J Phys Chem B 2017; 121:9126-9140. [PMID: 28879767 DOI: 10.1021/acs.jpcb.7b06591] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Protegrin-1 is an 18-residue β-hairpin antimicrobial peptide (AMP) that has been suggested to form transmembrane β-barrels in biological membranes. However, alternative structures have also been proposed. Here, we performed multimicrosecond, all-atom molecular dynamics simulations of various protegrin-1 oligomers on the membrane surface and in transmembrane topologies. The membrane surface simulations indicated that protegrin dimers are stable, whereas trimers and tetramers break down. Tetrameric arcs remained stably inserted in lipid membranes, but the pore water was displaced by lipid molecules. Unsheared protegrin β-barrels opened into β-sheets that surrounded stable aqueous pores, whereas tilted barrels with sheared hydrogen bonding patterns were stable in most topologies. A third type of observed pore consisted of multiple small oligomers surrounding a small, partially lipidic pore. We also considered the β-hairpin AMP tachyplesin, which showed less tendency to oligomerize than protegrin: the octameric bundle resulted in small pores surrounded by six peptides as monomers and dimers, with some peptides returning to the membrane surface. The results imply that multiple configurations of protegrin oligomers may produce aqueous pores and illustrate the relationship between topology and putative steps in protegrin-1's pore formation. However, the long-term stability of these structures needs to be assessed further.
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Affiliation(s)
- Richard Lipkin
- Department of Chemistry, City College of New York , 160 Convent Avenue, New York, New York 10031, United States.,Graduate Program in Chemistry, The Graduate Center, City University of New York , 365 Fifth Avenue, New York, New York 10016, United States
| | - Almudena Pino-Angeles
- Department of Chemistry, City College of New York , 160 Convent Avenue, New York, New York 10031, United States
| | - Themis Lazaridis
- Department of Chemistry, City College of New York , 160 Convent Avenue, New York, New York 10031, United States
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The importance of cyclic structure for Labaditin on its antimicrobial activity against Staphylococcus aureus. Colloids Surf B Biointerfaces 2016; 148:453-459. [PMID: 27665378 DOI: 10.1016/j.colsurfb.2016.09.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 09/04/2016] [Accepted: 09/11/2016] [Indexed: 01/24/2023]
Abstract
Antimicrobial resistance has reached alarming levels in many countries, thus leading to a search for new classes of antibiotics, such as antimicrobial peptides whose activity is exerted by interacting specifically with the microorganism membrane. In this study, we investigate the molecular-level mechanism of action for Labaditin (Lo), a 10-amino acid residue cyclic peptide from Jatropha multifida with known bactericidal activity against Streptococcus mutans. We show that Lo is also effective against Staphylococcus aureus (S. aureus) but this does not apply to its linear analogue (L1). Using polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), we observed with that the secondary structure of Lo was preserved upon interacting with Langmuir monolayers from a phospholipid mixture mimicking S. aureus membrane, in contrast to L1. This structure preservation for the rigid, cyclic Lo is key for the self-assembly of peptide nanotubes that induce pore formation in large unilamellar vesicles (LUVs), according to permeability assays and dynamic light scattering measurements. In summary, the comparison between Labaditin (Lo) and its linear analogue L1 allowed us to infer that the bactericidal activity of Lo is more related to its interaction with the membrane. It does not require specific metabolic targets, which makes cyclic peptides promising for antibiotics without bacteria resistance.
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15
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Bactericidal Effects and Mechanism of Action of Olanexidine Gluconate, a New Antiseptic. Antimicrob Agents Chemother 2015; 59:4551-9. [PMID: 25987609 DOI: 10.1128/aac.05048-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 05/11/2015] [Indexed: 01/02/2023] Open
Abstract
Olanexidine gluconate [1-(3,4-dichlorobenzyl)-5-octylbiguanide gluconate] (development code OPB-2045G) is a new monobiguanide compound with bactericidal activity. In this study, we assessed its spectrum of bactericidal activity and mechanism of action. The minimal bactericidal concentrations of the compound for 30-, 60-, and 180-s exposures were determined with the microdilution method using a neutralizer against 320 bacterial strains from culture collections and clinical isolates. Based on the results, the estimated bactericidal olanexidine concentrations with 180-s exposures were 869 μg/ml for Gram-positive cocci (155 strains), 109 μg/ml for Gram-positive bacilli (29 strains), and 434 μg/ml for Gram-negative bacteria (136 strains). Olanexidine was active against a wide range of bacteria, especially Gram-positive cocci, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, and had a spectrum of bactericidal activity comparable to that of commercial antiseptics, such as chlorhexidine and povidone-iodine. In vitro experiments exploring its mechanism of action indicated that olanexidine (i) interacts with the bacterial surface molecules, such as lipopolysaccharide and lipoteichoic acid, (ii) disrupts the cell membranes of liposomes, which are artificial bacterial membrane models, (iii) enhances the membrane permeability of Escherichia coli, (iv) disrupts the membrane integrity of S. aureus, and (v) denatures proteins at relatively high concentrations (≥160 μg/ml). These results indicate that olanexidine probably binds to the cell membrane, disrupts membrane integrity, and its bacteriostatic and bactericidal effects are caused by irreversible leakage of intracellular components. At relatively high concentrations, olanexidine aggregates cells by denaturing proteins. This mechanism differs slightly from that of a similar biguanide compound, chlorhexidine.
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16
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Haney EF, Nguyen LT, Schibli DJ, Vogel HJ. Design of a novel tryptophan-rich membrane-active antimicrobial peptide from the membrane-proximal region of the HIV glycoprotein, gp41. Beilstein J Org Chem 2012; 8:1172-84. [PMID: 23019445 PMCID: PMC3458735 DOI: 10.3762/bjoc.8.130] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/21/2012] [Indexed: 11/23/2022] Open
Abstract
A number of physicochemical characteristics have been described which contribute to the biological activity of antimicrobial peptides. This information was used to design a novel antimicrobial peptide sequence by using an intrinsically inactive membrane-associated peptide derived from the HIV glycoprotein, gp41, as a starting scaffold. This peptide corresponds to the tryptophan-rich membrane-proximal region of gp41, which is known to interact at the interfacial region of the viral membrane and adopts a helical structure in the presence of lipids. Three synthetic peptides were designed to increase the net positive charge and amphipathicity of this 19-residue peptide. Ultimately, the peptide with the greatest degree of amphipathicity and largest positive charge proved to be the most potent antimicrobial, and this peptide could be further modified to improve the antimicrobial activity. However, the other two peptides were relatively ineffective antimicrobials and instead proved to be extremely hemolytic. This work demonstrates a novel approach for the design of unexplored antimicrobial peptide sequences but it also reveals that the biological and cytotoxic activities of these polypeptides depend on a number of interrelated factors.
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Affiliation(s)
- Evan F Haney
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4
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17
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Saravanan R, Mohanram H, Joshi M, Domadia PN, Torres J, Ruedl C, Bhattacharjya S. Structure, activity and interactions of the cysteine deleted analog of tachyplesin-1 with lipopolysaccharide micelle: Mechanistic insights into outer-membrane permeabilization and endotoxin neutralization. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:1613-24. [DOI: 10.1016/j.bbamem.2012.03.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 03/14/2012] [Accepted: 03/16/2012] [Indexed: 12/17/2022]
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18
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Pan CY, Chen JY, Cheng YSE, Chen CY, Ni IH, Sheen JF, Pan YL, Kuo CM. Gene expression and localization of the epinecidin-1 antimicrobial peptide in the grouper (Epinephelus coioides), and its role in protecting fish against pathogenic infection. DNA Cell Biol 2007; 26:403-13. [PMID: 17570764 DOI: 10.1089/dna.2006.0564] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Epinecidin-1 is an antimicrobial peptide and plays a vital role in protecting fish against pathogenic infection. As a mimic of a grouper epinecidin-1 peptide, it has tertiary structures that closely resemble those of pleurocidin found in the winter flounder (Pleuronectes americanus). The tissue-specific, lipopolysaccharide (LPS)-stimulation-specific, and poly(I):poly(C)-stimulation-specific expressions of the grouper (Epinephelus coioides) epinecidin-1 antimicrobial peptide were determined using a comparative reverse-transcription polymerase chain reaction. Results of the tissue distribution analysis revealed high levels of epinecidin-1 messenger RNA (mRNA) in the head kidneys, intestines, and skin. Expression of epinecidin-1 mRNA was dose-dependently stimulated by both LPS and poly(I):poly(C). Immunohistochemical analysis with the polyclonal antiserum of a grouper epinecidin-1 peptide (rabbit polyclonal antibody) showed that the peptide was localized with the epinecidin-1 antibody in the gills and intestines. Two synthetic peptides of the grouper epinecidin-1 peptide (g-ple 22-51 and g-ple 22-42) and one winter flounder pleurocidin as a control exhibited high antimicrobial activities against gram-negative or gram-positive bacteria. In addition, peptide treatment was effective in promoting a significant increase in fish survival after the injection of Vibrio vulnificus in tilapia (Oreochromis mossambicus) and grouper. These results are relevant to the design of prophylactic and therapeutic strategies to counter bacterial infections, especially for preventing or ameliorating immune defects in fish during bacterial infections.
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Affiliation(s)
- Chia-Yu Pan
- Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung, Taiwan
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19
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Imura Y, Nishida M, Ogawa Y, Takakura Y, Matsuzaki K. Action mechanism of tachyplesin I and effects of PEGylation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1160-9. [PMID: 17320042 DOI: 10.1016/j.bbamem.2007.01.005] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 12/26/2006] [Accepted: 01/10/2007] [Indexed: 10/23/2022]
Abstract
PEGylation of protein and peptide drugs is frequently used to improve in vivo efficacy. We investigated the action mechanism of tachyplesin I, a membrane-acting cyclic antimicrobial peptide from Tachypleus tridentatus and the effects of PEGylation on the mechanism. The PEGylated peptide induced the leakage of calcein from egg yolk L-alpha-phosphatidylglycerol/egg yolk L-alpha-phosphatidylcholine large unilamellar vesicles similarly to the parent peptide. Both peptides induced lipid flip-flop coupled to leakage and was translocated into the inner leaflet of the bilayer, indicating that tachyplesin I forms a toroidal pore and that PEGylation did not alter the basic mechanism of membrane permeabilization of the parent peptide. Despite their similar activities against model membranes, the peptides showed very different biological activities. The cytotoxicity of tachyplesin I was greatly reduced by PEGylation, although the antimicrobial activity was significantly weakened. We investigated the enhancement of the permeability of inner membranes induced by the peptides. Our results suggested that outer membranes and peptidoglycan layers play an inhibitory role in the permeation of the PEG moiety. Furthermore, a reduction in DNA binding by PEGylation may also contribute to the weak activity of the PEGylated peptide.
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Affiliation(s)
- Yuichi Imura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
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20
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Mason KM, Bruggeman ME, Munson RS, Bakaletz LO. The non-typeable Haemophilus influenzae Sap transporter provides a mechanism of antimicrobial peptide resistance and SapD-dependent potassium acquisition. Mol Microbiol 2006; 62:1357-72. [PMID: 17064364 DOI: 10.1111/j.1365-2958.2006.05460.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We have shown that non-typeable Haemophilus influenzae (NTHI) resists killing by antimicrobial peptides (APs). A mutant defective in expression of the sap (sensitivity to antimicrobial peptides) gene cluster product SapA is sensitive to killing by APs and is significantly attenuated in its ability to survive in a chinchilla model of otitis media compared with the parent strain. In NTHI, SapA is believed to function as the periplasmic solute binding protein of an ABC transporter. Here, we demonstrated that recombinant chinchilla beta defensin-1 specifically interacted with recombinant SapA and that AP exposure increased expression of the sap operon. We further demonstrated that the putative Sap transporter ATPase protein, SapD, was required for AP resistance as well as potassium uptake in NTHI strain 86-028NP. Loss of SapD additionally abrogated NTHI survival in vivo. Complementation of the sapD mutation restored the ability to grow in potassium-limited medium, resistance to AP-mediated killing and survival in vivo. Collectively, these data support a mechanism of Sap system-mediated resistance to APs that depends on Sap-dependent transport of APs and a Sap-dependent restoration of potassium homeostasis. Thus, NTHI required a functional Sap system to mediate bacterial survival and pathogenesis in vivo.
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Affiliation(s)
- Kevin M Mason
- Columbus Children's Research Institute and The Ohio State University College of Medicine and Public Health, Columbus, OH, USA
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21
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Zhang HT, Wu J, Zhang HF, Zhu QF. Efflux of potassium ion is an important reason of HL-60 cells apoptosis induced by tachyplesin. Acta Pharmacol Sin 2006; 27:1367-74. [PMID: 17007745 DOI: 10.1111/j.1745-7254.2006.00377.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
AIM To investigate the role of intercellular potassium in tachyplesin-induced HL-60 cells apoptosis. METHODS The concentration of intercellular potassium, cell volume and mitochondrial membrane potential were examined by flow cytometry. RESULTS The concentration of intercellular potassium reduced in a time-dependent manner in tachyplesin-treated HL-60 cells. In addition, the loss of mitochondrial membrane potential was tightly coupled with the shrinkage of cell volume. Different caspase inhibitors protected against DNA degradation but did not prevent the loss of HL-60 cell viability induced by tachyplesin. Ba2+, which was a kind of blocker of volume-regulatory K+ channels, increased the viability of tachyplesin-treated HL-60 cells and maintained mitochondrial membrane potential and cell volume. CONCLUSION Efflux of K+ was an important reason for apoptosis in tachyplesin-treated HL-60 cells. Efflux of K+ affected the viability of tachyplesin-treated HL-60 cells independent of the process of caspase activation.
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Affiliation(s)
- Hai-tao Zhang
- Institute of Biochemistry and Molecular Biology, Guangdong Medical College, Zhanjiang 524023, China.
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22
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Ramamoorthy A, Thennarasu S, Tan A, Gottipati K, Sreekumar S, Heyl DL, An FYP, Shelburne CE. Deletion of all cysteines in tachyplesin I abolishes hemolytic activity and retains antimicrobial activity and lipopolysaccharide selective binding. Biochemistry 2006; 45:6529-40. [PMID: 16700563 PMCID: PMC2515376 DOI: 10.1021/bi052629q] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tachyplesin I is a cyclic beta-sheet antimicrobial peptide isolated from the hemocytes of Tachypleus tridentatus. The four cysteine residues in tachyplesin I play a structural role in imparting amphipathicity to the peptide which has been shown to be essential for its activity. We investigated the role of amphipathicity using an analogue of tachyplesin I (TP-I), CDT (KWFRVYRGIYRRR-NH(2)), in which all four cysteines were deleted. Like TP-I, CDT shows antimicrobial activity and disrupts Escherichia coli outer membrane and model membranes mimicking bacterial inner membranes at micromolar concentrations. The CDT peptide does not cause hemolysis up to 200 microg/mL while TP-I showed about 10% hemolysis at 100 microg/mL and about 25% hemolysis at 150 microg/mL. Peptide-into-lipid titrations under isothermal conditions reveal that the interaction of CDT with lipid membranes is an enthalpy-driven process. Binding assays performed using fluorometry demonstrate that the peptide CDT binds and inserts into only negatively charged membranes. The peptide-induced thermotropic phase transition of MLVs formed of DMPC and the DMPC/DMPG (7:3) mixture suggests specific lipid-peptide interactions. The circular dichroism study shows that the peptide exists as an unordered structure in an aqueous buffer and adopts a more ordered beta-structure upon binding to negatively charged membrane. The NMR data suggest that CDT binding to negatively charged bilayers induces a change in the lipid headgroup conformation with the lipid headgroup moving out of the bilayer surface toward the water phase, and therefore, a barrel stave mechanism of membrane disruption is unlikely as the peptide is located near the headgroup region of lipids. The lamellar phase (31)P chemical shift spectra observed at various concentrations of the peptide in bilayers suggest that the peptide may function neither via fragmentation of bilayers nor by promoting nonlamellar structures. NMR and fluorescence data suggest that the presence of cholesterol inhibits the peptide binding to the bilayers. These properties help to explain that cysteine residues may not contribute to antimicrobial activity and that the loss of hemolytic activity is due to lack of hydrophobicity and amphipathicity.
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Affiliation(s)
- Ayyalusamy Ramamoorthy
- Department of Chemistry and Biophysics Research Division, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
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23
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Nguyen LT, Schibli DJ, Vogel HJ. Structural studies and model membrane interactions of two peptides derived from bovine lactoferricin. J Pept Sci 2005; 11:379-89. [PMID: 15635665 DOI: 10.1002/psc.629] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The powerful antimicrobial properties of bovine lactoferricin (LfcinB) make it attractive for the development of new antimicrobial agents. An 11-residue linear peptide portion of LfcinB has been reported to have similar antimicrobial activity to lactoferricin itself, but with lower hemolytic activity. The membrane-binding and membrane-perturbing properties of this peptide were studied together with an amidated synthetic version with an added disulfide bond, which was designed to confer increased stability and possibly activity. The antimicrobial and cytotoxic properties of the peptides were measured against Staphylococcus aureus and Escherichia coli and by hemolysis assays. The peptides were also tested in an anti-cancer assay against neuroblastoma cell lines. Vesicle disruption caused by these LfcinB derivatives was studied using the fluorescent reporter molecule calcein. The extent of burial of the two Trp residues in membrane mimetic environments were quantitated by fluorescence. Finally, the solution NMR structures of the peptides bound to SDS micelles were determined to provide insight into their membrane bound state. The cyclic peptide was found to have greater antimicrobial potency than its linear counterpart. Consistent with this property, the two Trp residues of the modified peptide were suggested to be embedded deeper into the membrane. Although both peptides adopt an amphipathic structure without any regular alpha-helical or beta-sheet conformation, the 3D-structures revealed a clearer partitioning of the cationic and hydrophobic faces for the cyclic peptide.
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Affiliation(s)
- Leonard T Nguyen
- Structural Biology Research Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta, T2N 1N4 Canada
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24
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Affiliation(s)
- J Andy Tincu
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, 8602 La Jolla Shores Dr., MC 0204, San Diego, La Jolla, CA 92093-0204.
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25
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Gibbs GM, Davidson BE, Hillier AJ. Novel expression system for large-scale production and purification of recombinant class IIa bacteriocins and its application to piscicolin 126. Appl Environ Microbiol 2004; 70:3292-7. [PMID: 15184123 PMCID: PMC427731 DOI: 10.1128/aem.70.6.3292-3297.2004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Piscicolin 126 is a class IIa bacteriocin isolated from Carnobacterium piscicola JG126 that exhibits strong activity against Listeria monocytogenes. The gene encoding mature piscicolin 126 (m-pisA) was cloned into an Escherichia coli expression system and expressed as a thioredoxin-piscicolin 126 fusion protein that was purified by affinity chromatography. Purified recombinant piscicolin 126 was obtained after CNBr cleavage of the fusion protein followed by reversed-phase chromatography. Recombinant piscicolin 126 contained a single disulfide bond and had a mass identical to that of native piscicolin 126. This novel bacteriocin expression system generated approximately 26 mg of purified bacteriocin from 1 liter of E. coli culture. The purified recombinant piscicolin 126 acted by disruption of the bacterial cell membrane.
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Affiliation(s)
- Gerard M Gibbs
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3052, Australia
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26
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Hornef MW, Wick MJ, Rhen M, Normark S. Bacterial strategies for overcoming host innate and adaptive immune responses. Nat Immunol 2002; 3:1033-40. [PMID: 12407412 DOI: 10.1038/ni1102-1033] [Citation(s) in RCA: 296] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In higher organisms a variety of host defense mechanisms control the resident microflora and, in most cases, effectively prevent invasive microbial disease. However, it appears that microbial organisms have coevolved with their hosts to overcome protective host barriers and, in selected cases, actually take advantage of innate host responses. Many microbial pathogens avoid host recognition or dampen the subsequent immune activation through sophisticated interactions with host responses, but some pathogens benefit from the stimulation of inflammatory reactions. This review will describe the spectrum of strategies used by microbes to avoid or provoke activation of the host's immune response as well as our current understanding of the role this immunomodulatory interference plays during microbial pathogenesis.
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Affiliation(s)
- Mathias W Hornef
- Microbiology and Tumor Biology Center, Karolinska Institutet, Nobelsväg 16, SE-17177 Stockholm, Sweden
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27
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Kobayashi S. [Bacteria-selective synergism between the antimicrobial peptides magainin 2 and tachyplesin I: toward cocktail therapy]. YAKUGAKU ZASSHI 2002; 122:967-73. [PMID: 12440153 DOI: 10.1248/yakushi.122.967] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Magainin 2 and tachyplesin I (T-SS) are membrane-permeabilizing antimicrobial peptides discovered in frog skin and horseshoe crab hemolymph, respectively. They are classified into different secondary structural classes, i.e., alpha-helix and cyclic beta-sheet, respectively. We found that F5W-magainin 2 (MG2) and T-SS showed marked synergistic effects against gram-negative and-positive bacteria without enhancing hemolytic activity as a measure of toxicity. The results of dye-release experiments using liposomes suggested that the selective synergism is mainly due to anionic phospholipid-specific synergism in membrane permeabilization. Furthermore, the cyclic structure of T-SS was found to be necessary for synergism because a linear analogue of T-SS did not show good synergism with MG2. These novel observations suggest the possibility of development of cocktail therapeutic regimens using combinations of antimicrobial peptides.
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Affiliation(s)
- Satoe Kobayashi
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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28
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Hirakura Y, Kobayashi S, Matsuzaki K. Specific interactions of the antimicrobial peptide cyclic beta-sheet tachyplesin I with lipopolysaccharides. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1562:32-6. [PMID: 11988219 DOI: 10.1016/s0005-2736(02)00358-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The cyclic beta-sheet antimicrobial peptide tachyplesin I (T-SS) was found to show 280-fold higher affinity for lipopolysaccharides (LPS) compared with acidic phospholipids, whereas the linear alpha-helical peptide F5W-magainin 2 (MG2) could not discriminate between LPS and acidic phospholipids. The recognition site was the lipid A moiety and the cyclic structure was crucial to this specific binding. The cyclic structure also endowed the peptide with very rapid outer membrane (OM) permeabilization.
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Affiliation(s)
- Yutaka Hirakura
- Advanced Research Center for Human Sciences, Waseda University, Nishi-Tokyo, Tokyo 202-0021, Japan
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29
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Abstract
The authors have discovered a highly selective CXCR4 antagonist, T22 ([Tyr5,12, Lys7]-polyphemusin II), and its shortened potent analogs, T140 and TC14012, which strongly inhibit the T-cell line-tropic HIV-1 (X4-HIV-1) infection through their specific binding to a chemokine receptor, CXCR4. CXCR4 is a major coreceptor (second receptor) for the entry of X4-HIV-1 into T-cells. These peptides have been found through the structure-activity relationship (SAR) study on tachyplesins and polyphemusins, which function as self-defense peptides of horseshoe crabs with immature immune systems. T140 and TC14012 showed the highest level of anti-HIV activity and antagonism of target cell entry by X4-HIV-1 among all the CXCR4 antagonists that have been reported to date. Additionally, bifunctional anti-HIV agents based on the specific CXCR4 antagonists (T140 analogs)-3'-azido-3'-deoxythymidine (AZT) conjugation have been synthesized and evaluated, since T140 analogs can possibly work as a carrier of AZT targeting T-cells due to their specific affinity for CXCR4 on T-cells. T22 have two disulfide bonds and a Trp residue in the molecule. In connection with this study, novel facile and side-reaction-free methodologies for disulfide bond formation have been established for the increase of the efficiency of SAR studies. Furthermore, the completely stereocontrolled synthetic process for a couple of (E)-alkene dipeptide isosteres starting from L-amino acid has been established in order to facilitate nonpeptidylation studies on peptide-lead candidates. In this review, the authors wish to summarize our recent research on the development of specific antagonists against the HIV second receptor CXCR4, involving studies on the establishment of efficient methodologies for the facile synthesis of peptides and peptide mimetics.
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Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
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30
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Tamamura H, Omagari A, Hiramatsu K, Gotoh K, Kanamoto T, Xu Y, Kodama E, Matsuoka M, Hattori T, Yamamoto N, Nakashima H, Otaka A, Fujii N. Development of specific CXCR4 inhibitors possessing high selectivity indexes as well as complete stability in serum based on an anti-HIV peptide T140. Bioorg Med Chem Lett 2001; 11:1897-902. [PMID: 11459656 DOI: 10.1016/s0960-894x(01)00323-7] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We previously reported a truncated polyphemusin peptide analogue, T140, which efficiently inhibits infection of target cells by T-cell line-tropic strains of HIV-1 (X4-HIV-1) through its specific binding to a chemokine receptor, CXCR4. We have found that T140 is not stable in feline serum due to the cleavage of the C-terminal Arg,(14) indispensable for anti-HIV activity. On the other hand, a C-terminally amidated analogue of T140, TZ14004, has been found to be completely stable in incubation in the serum for 2 days. The C-terminal amide is thought to be needed for stability in serum. However, TZ14004 does not have fairly strong anti-HIV activity, but has relatively strong cytotoxicity, probably due to an increase by +1 charge from total +7 charges of T140. In our previous study, the number of total +6 charges seemed to be a suitable balance between activity and cytotoxicity. In this study, we have conducted a double-L-citrulline (Cit)-scanning study on TZ14004 based on the C-terminally amidated form in due consideration of the total net charges in the whole molecule to find novel effective CXCR4 inhibitors, TN14003 ([Cit(6)]-T140 with the C-terminal amide) and TC14012 ([Cit(6), D-Cit(8)]-T140 with the C-terminal amide), which possess high selectivity indexes (SIs) and complete stability in feline serum.
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Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, 606-8501, Kyoto, Japan.
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31
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Affiliation(s)
- T Ganz
- Department of Medicine and the Department of Pathology, University of California at Los Angeles, School of Medicine, Los Angeles, California 90095, USA.
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32
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Mozsolits H, Wirth HJ, Werkmeister J, Aguilar MI. Analysis of antimicrobial peptide interactions with hybrid bilayer membrane systems using surface plasmon resonance. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1512:64-76. [PMID: 11334625 DOI: 10.1016/s0005-2736(01)00303-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The lipid binding behaviour of the antimicrobial peptides magainin 1, melittin and the C-terminally truncated analogue of melittin (21Q) was studied with a hybrid bilayer membrane system using surface plasmon resonance. In particular, the hydrophobic association chip was used which is composed of long chain alkanethiol molecules upon which liposomes adsorb spontaneously to create a hybrid bilayer membrane surface. Multiple sets of sensorgrams with different peptide concentrations were generated. Linearisation analysis and curve fitting using numerical integration analysis were performed to derive estimates for the association (k(a)) and dissociation (k(d)) rate constants. The results demonstrated that magainin 1 preferentially interacted with negatively charged dimyristoyl-L-alpha-phosphatidyl-DL-glycerol (DMPG), while melittin interacted with both zwitterionic dimyristoyl-L-alpha-phosphatidylcholine and anionic DMPG. In contrast, the C-terminally truncated melittin analogue, 21Q, exhibited lower binding affinity for both lipids, showing that the positively charged C-terminus of melittin greatly influences its membrane binding properties. Furthermore the results also demonstrated that these antimicrobial peptides bind to the lipids initially via electrostatic interactions which then enhances the subsequent hydrophobic binding. The biosensor results were correlated with the conformation of the peptides determined by circular dichroism analysis, which indicated that high alpha-helicity was associated with high binding affinity. Overall, the results demonstrated that biosensor technology provides a new experimental approach to the study of peptide-membrane interactions through the rapid determination of the binding affinity of bioactive peptides for phospholipids.
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Affiliation(s)
- H Mozsolits
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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33
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Boggs JM, Jo E, Polozov IV, Epand RF, Anantharamaiah GM, Blazyk J, Epand RM. Effect of magainin, class L, and class A amphipathic peptides on fatty acid spin labels in lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1511:28-41. [PMID: 11248202 DOI: 10.1016/s0005-2736(00)00379-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Magainins and other antimicrobial peptides increase ion flux across the membrane. They may do this by forming some type of pore or by perturbing lipid organization due to peptide lying on the bilayer surface. In order to determine if magainins perturb the lipid sufficiently to permeabilize the bilayer, their effect on the motion of fatty acid and lipid spin labels in phosphatidylcholine/phosphatidylglycerol (PC/PG) lipid vesicles was determined. Their effect was compared to two synthetic peptides, 18L and Ac-18A-NH(2), designed to mimic the naturally occurring classes of lytic (class L) and apolipoprotein (class A) amphipathic helices, respectively. We show that although magainins and 18L both had significant effects on lipid chain order, much greater than Ac-18A-NH(2), there was no correlation between these effects and the relative ability of these three peptide classes to permeabilize PC/PG vesicles in the order magainins=Ac-18A-NH(2) >> 18L. This suggests that the perturbing effects of magainins on lipid chain order at permeabilizing concentrations are not directly responsible for the increased leakage of vesicle contents. The greater ability of the magainins to permeabilize PC/PG vesicles relative to 18L is thus more likely due to formation of some type of pore by magainins. The greater ability of Ac-18A-NH(2) relative to 18L to permeabilize PC/PG vesicles despite its lack of disordering effect must be due to its ability to cause membrane fragmentation. Effects of these peptides on other lipids indicated that the mechanism by which they permeabilize lipid bilayers depends both on the peptide and on the lipid composition of the vesicles.
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Affiliation(s)
- J M Boggs
- Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
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34
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Sassaki GL, Cruz LM, Gorin PA, Lacomini M. Fatty acid composition of lipids present in selected lichenized fungi: a chemotyping study. Lipids 2001; 36:167-74. [PMID: 11269697 DOI: 10.1007/s11745-001-0703-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The total-lipid composition of 21 lichens of the ascomycetous genera Cladonia (11) and Cladina (1) of the family Cladoniacea, Cladia (1), Parmotrema (3), Ramalina (2), Leptogium (1), Cetraria (1), and the basidiomycetous genus Dictyonema (1) was determined. Analyses of those of Dictyonema glabratum were carried out with a total extract and those obtained after successive extractions with various solvents. Each extract was partitioned between n-heptane/isopropanol and 1 M sulfuric acid, giving triglycerides (TG) in the upper phase. Extracts were methanolyzed and the resulting methyl esters were analyzed by gas chromatography-mass spectrometry. Methanolyzates of TG unexpectedly contained esters of 9-oxodecanoic, 9-methyl-tetradecanoic, 6-methyl-tetradecanoic, 3-hydroxy-decanoic, nonanedioic, and decanedioic acids, as well as common fatty acids. Fatty acid methyl ester profiles from the lichens were submitted to cluster analysis, and the resulting dendogram showed a cluster consistent with Cladonia spp., suggesting an efficient aid to lichen taxonomy. The total carbohydrate content of each lipid extract was determined by a modified phenol-sulfuric acid method, which compensated for the presence of pigments.
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Affiliation(s)
- G L Sassaki
- Departamento de Bioquímica, Universidade Federal do Paraná, Curitiba-PR, Brazil
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35
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Tamamura H, Omagari A, Oishi S, Kanamoto T, Yamamoto N, Peiper SC, Nakashima H, Otaka A, Fujii N. Pharmacophore identification of a specific CXCR4 inhibitor, T140, leads to development of effective anti-HIV agents with very high selectivity indexes. Bioorg Med Chem Lett 2000; 10:2633-7. [PMID: 11128640 DOI: 10.1016/s0960-894x(00)00535-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A polyphemusin peptide analogue, T22 ([Tyr(5,12), Lys7]-polyphemusin II), and its shortened potent analogues, T134 (des-[Cys(8,13), Tyr(9,12)]-[D-Lys10, Pro11, L-citrulline16]-T22 without C-terminal amide) and T140 [[L-3-(2-naphthyl)alanine3]-T134], strongly inhibit the T-cell line-tropic (T-tropic) HIV-1 infection through their specific binding to a chemokine receptor, CXCR4. T22 is an extremely basic peptide possessing five Arg and three Lys residues in the molecule. In our previous study, we found that there is an apparent correlation in the T22-related peptides between the number of total positive charges and anti-HIV activity or cytotoxicity. Here, we have conducted the conventional Ala-scanning study in order to define the anti-HIV activity pharmacophore of T140 (the strongest analogue among our compounds) and identified four indispensable amino acid residues (Arg2, Nal3, Tyr5, and Arg14). Based on this result, a series of L-citrulline (Cit)-substituted analogues of T140 with decreased net positive charges have been synthesized and evaluated in terms of anti-HIV activity and cytotoxicity. As a result, novel effective inhibitors, TC14003 and TC14005, possessing higher selectivity indexes (SIs, 50% cytotoxic concentration/50% effective concentration) than that of T140 have been developed.
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Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Japan.
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36
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Matsuzaki K. Why and how are peptide-lipid interactions utilized for self-defense? Magainins and tachyplesins as archetypes. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1462:1-10. [PMID: 10590299 DOI: 10.1016/s0005-2736(99)00197-2] [Citation(s) in RCA: 714] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Animals as well as plants defend themselves against invading pathogenic microorganisms utilizing cationic antimicrobial peptides, which rapidly kill various microbes without exerting toxicity against the host. Physicochemical peptide-lipid interactions provide attractive mechanisms for innate immunity. Many of these peptides form cationic amphipathic secondary structures, typically alpha-helices and beta-sheets, which can selectively interact with anionic bacterial membranes by the aid of electrostatic interactions. Rapid, peptide-induced membrane permeabilization is an effective mechanism of antimicrobial action. This review article summarizes interactions with lipid bilayers of magainins (alpha-helix) and tachyplesins (beta-sheet) discovered in frog skin and horseshoe crab hemolymph, respectively, as archetypes, emphasizing that the mode of interaction is strongly dependent on the physicochemical properties not only of the peptide, but also of the target membrane.
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Affiliation(s)
- K Matsuzaki
- Graduate School of Biostudies, Kyoto University, Yoshida-Shimoadachi-Cho 46-29, Sakyo-ku, Kyoto, Japan.
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37
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Murakami T, Zhang TY, Koyanagi Y, Tanaka Y, Kim J, Suzuki Y, Minoguchi S, Tamamura H, Waki M, Matsumoto A, Fujii N, Shida H, Hoxie JA, Peiper SC, Yamamoto N. Inhibitory mechanism of the CXCR4 antagonist T22 against human immunodeficiency virus type 1 infection. J Virol 1999; 73:7489-96. [PMID: 10438838 PMCID: PMC104275 DOI: 10.1128/jvi.73.9.7489-7496.1999] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We recently reported that a cationic peptide, T22 ([Tyr(5,12), Lys(7)]-polyphemusin II), specifically inhibits human immunodeficiency virus type 1 (HIV-1) infection mediated by CXCR4 (T. Murakami et al., J. Exp. Med. 186:1389-1393, 1997). Here we demonstrate that T22 effectively inhibits replication of T-tropic HIV-1, including primary isolates, but not of non-T-tropic strains. By using a panel of chimeric viruses between T- and M-tropic HIV-1 strains, viral determinants for T22 susceptibility were mapped to the V3 loop region of gp120. T22 bound to CXCR4 and interfered with stromal-cell-derived factor-1alpha-CXCR4 interactions in a competitive manner. Blocking of anti-CXCR4 monoclonal antibodies by T22 suggested that the peptide interacts with the N terminus and two of the extracellular loops of CXCR4. Furthermore, the inhibition of cell-cell fusion in cells expressing CXCR4/CXCR2 chimeric receptors suggested that determinants for sensitivity of CXCR4 to T22 include the three extracellular loops of the coreceptor.
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Affiliation(s)
- T Murakami
- Department of Microbiology and Molecular Virology, Faculty of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8519, Japan
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38
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Determination of histamine release from mast cells using a histamine-sensitive membrane electrode. Anal Chim Acta 1999. [DOI: 10.1016/s0003-2670(99)00439-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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39
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El Jastimi R, Edwards K, Lafleur M. Characterization of permeability and morphological perturbations induced by nisin on phosphatidylcholine membranes. Biophys J 1999; 77:842-52. [PMID: 10423430 PMCID: PMC1300376 DOI: 10.1016/s0006-3495(99)76936-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Nisin is an antimicrobial peptide used as food preservative. To gain some insights into the hypothesis that its bactericidal activity is due to the perturbation of the lipid fraction of the bacterial plasmic membrane, we have investigated the effect of nisin on model phosphatidylcholine (PC) membranes. We show that nisin affects the PC membrane permeability, and this perturbation is modulated by the lipid composition. Nisin-induced leakage from PC vesicles is inhibited by the presence of cholesterol. This inhibition is associated with the formation of a liquid ordered phase in the presence of cholesterol, which most likely reduces nisin affinity for the membrane. Conversely, phosphatidylglycerol (PG), an anionic lipid, promotes nisin-induced leakage, and this promotion is associated with an increased affinity of the peptide for the bilayer because nisin is a cationic peptide. When the electrostatic interactions are encouraged by the presence of 70 mol% PG in PC, the inhibitory effect of cholesterol is not observed anymore. Nisin drastically modifies the morphology of the dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) multilamellar dispersion without causing a significant change in the gel-to-liquid crystalline phase transition of the lipid. The morphological changes are observed from (31)P and (2)H NMR and cryo-electron microscopy. From the NMR point of view, the interactions giving rise to a broad signal (quadrupolar interactions and chemical shift anisotropy for (2)H NMR and (31)P NMR, respectively) are partly averaged out in the presence of nisin. This phenomenon is interpreted by the formation of curved lipid planes that lead to the lipid lateral diffusion occurring in the intermediate motional regime. By cryo-electron microscopy, large amorphous aggregates containing small dense globular particles are observed for samples quenched from 25 and 50 degrees C. Long thread-like structures are also observed in the fluid phase. A structural description of DPPC/nisin complex, consistent with the experimental observation, is proposed. The presence of 30 mol% cholesterol in DPPC completely inhibits the morphological changes induced by nisin. Therefore, it is concluded that nisin can significantly perturb PC bilayers from both the permeability and the structural points of view, and these perturbations are modulated by the lipidic species in the bilayer.
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Affiliation(s)
- R El Jastimi
- Department of Chemistry, Université de Montréal, Montréal, Québec H3C 3J7, Canada
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40
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Ganz T, Lehrer RI. Antibiotic peptides from higher eukaryotes: biology and applications. MOLECULAR MEDICINE TODAY 1999; 5:292-7. [PMID: 10377520 DOI: 10.1016/s1357-4310(99)01490-2] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Gene-encoded antibiotic peptides are increasingly being recognized as effector molecules of host defense in plants and animals. Studies of antimicrobial peptides are providing new insights into the dynamic interactions between microbes and their hosts, and are generating new paradigms for the pathogenesis and treatment of diseases. Because antimicrobial peptides of higher eukaryotes differ structurally from conventional antibiotics produced by bacteria and fungi, they offer novel templates for pharmaceutical compounds that could be effective against increasingly resistant microbes.
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Affiliation(s)
- T Ganz
- Dept of Medicine and the Will Rogers Institute for Pulmonary Research, UCLA School of Medicine, Los Angeles, CA 90095-1690, USA.
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41
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Tamamura H, Arakaki R, Funakoshi H, Imai M, Otaka A, Ibuka T, Nakashima H, Murakami T, Waki M, Matsumoto A, Yamamoto N, Fujii N. Effective lowly cytotoxic analogs of an HIV-cell fusion inhibitor, T22 ([Tyr5,12, Lys7]-polyphemusin II). Bioorg Med Chem 1998; 6:231-8. [PMID: 9547946 DOI: 10.1016/s0968-0896(97)10037-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A tachyplesin peptide analog, T22 ([Tyr5,12, Lys7]-polyphemusin II), and its shortened congener, TW70 (des-[Cys8,13, Tyr9,12]-[D-Lys10, Pro11]-T22) have strong anti-human immunodeficiency virus (HIV) activity, comparable to that of 3'-azido-2', 3'-dideoxythymidine (AZT). T22 and TW70 are extremely basic peptides, containing 5 Arg residues and 3 Lys residues. The number of positive charges might be related in part to high collateral cytotoxicities of T22 and TW70. Here we have synthesized several analogs, in which the number of positive charges has been reduced through amino acid substitutions using Glu or L-citrulline. As a result, several effective compounds have been found which possess higher selectivity indexes (SIs, 50% cytotoxic concentration/50% effective concentration) than those of T22 and TW70. Higher SIs were attributed mainly to a decrease in cytotoxicity.
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Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Japan. /
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42
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Cruz A, Casals C, Keough KM, Pérez-Gil J. Different modes of interaction of pulmonary surfactant protein SP-B in phosphatidylcholine bilayers. Biochem J 1997; 327 ( Pt 1):133-8. [PMID: 9355744 PMCID: PMC1218772 DOI: 10.1042/bj3270133] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Pulmonary surfactant-associated protein B (SP-B) has been incorporated into vesicles of dipalmitoyl phosphatidylcholine (DPPC) or egg yolk phosphatidylcholine (PC) by two different procedures to characterize the dependence of lipid-protein interactions on the method of reconstitution. In method A the protein was dissolved in a small volume of either methanol or 60% (v/v) acetonitrile and injected into an aqueous phase containing phospholipid vesicles. In method B the vesicles were prepared by injection of a mixture of phospholipid and SP-B dissolved in methanol or aqueous acetonitrile. Both methods of reconstitution led to the extensive interaction of SP-B with PC bilayers as demonstrated by co-migration during centrifugation, marked protection against proteolysis, change in the fluorescence emission intensity of SP-B, and protection of SP-B tryptophan fluorescence from quenching by acrylamide. SP-B promoted the rapid adsorption of DPPC on an air/liquid interface irrespective of the method of protein reconstitution. However, the interfacial adsorption activity of SP-B reconstituted by method B remained stable for hours, but that of SP-B prepared by method A decreased with time. Electron microscopy showed that the injection of SP-B into an aqueous phase containing PC or DPPC vesicles (method A) induced a rapid aggregation of vesicles. By contrast, a much longer time was required for detecting vesicle aggregation when the protein was reconstituted by co-injection of SP-B and phospholipids (method B). The presence of 5% (w/w) SP-B in DPPC bilayers prepared by method B broadened the differential scanning calorimetry thermogram and decreased the enthalpy of the transition. In contrast, the injection of SP-B into preformed DPPC vesicles (method A) did not influence the gel-to-liquid phase transition of DPPC bilayers. Taken together, these results indicate that the mode and extent of interaction of SP-B with surfactant phospholipids depends on the conditions of preparation of lipid/protein samples, and that care should be taken in the interpretation of findings from reconstituted systems on the role of these surfactant proteins in the alveolar space.
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Affiliation(s)
- A Cruz
- Departamento de Bioquímica y Biología Molecular I, Facultad Biología, Universidad Complutense, 28040 Madrid, Spain
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43
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Matsuzaki K, Sugishita K, Harada M, Fujii N, Miyajima K. Interactions of an antimicrobial peptide, magainin 2, with outer and inner membranes of Gram-negative bacteria. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1327:119-30. [PMID: 9247173 DOI: 10.1016/s0005-2736(97)00051-5] [Citation(s) in RCA: 271] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Magainin peptides, isolated from Xenopus skin, have broad spectra of antimicrobial activity and low toxicities to normal eukaryotic cells, thus being good candidates for therapeutic agents. The mechanism of action is considered to be the permeabilization of bacterial membranes. A number of studies using lipid vesicles have elucidated its molecular detail. However, their interactions with bacteria are not yet well understood. In this paper, we synthesized several magainin analogs with different charges (0 to +6) and hydrophobicities, and systematically studied their interactions with the outer and inner membranes of three species of Gram-negative bacteria (Escherichia coli, Acinetobacter calcoaceticus, Proteus vulgaris). The treatment of the E. coli cells with native magainin 2 (+4) immediately induced the efflux of the intracellular K+ ions and the cell death. A number of blebs were formed on the bacterial surface and the outer membrane became leaky. An increase in the peptide's positive charge enhanced the outer membrane permeabilization and the bactericidal activity. The cationic peptides also effectively permeabilized the inner membranes rich in acidic phospholipids, indicating the importance of electrostatic interactions. Substitution of Trp for Phe simultaneously increased the bactericidal activity and the hemolytic activity. A strategy to develop potent antimicrobial peptides was discussed on the basis of these results.
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Affiliation(s)
- K Matsuzaki
- Faculty of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Japan.
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44
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Berlose JP, Convert O, Derossi D, Brunissen A, Chassaing G. Conformational and associative behaviours of the third helix of antennapedia homeodomain in membrane-mimetic environments. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 242:372-86. [PMID: 8973656 DOI: 10.1111/j.1432-1033.1996.0372r.x] [Citation(s) in RCA: 138] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The third helix of antennapedia homeodomain pAntp-(43-58) can translocate through cell membrane and has been used as an intracellular vehicle for delivering peptides and oligonucleotides. The conformational and associative behaviour of two peptidic vectors pAntp-(43-58) and [Pro50] pAntp-(43-58) has been analyzed by different biophysical methods. pAntp-(43-58) adopts an amphipathic helical structure in 30% (by vol.) hexafluoroisopropanol, in perfluoro-tert-butanol and in the presence of SDS micelles. CD spectra indicate that the conformation of [Pro50]pAntp-(43-58) in contrast to pAntp-(43-58) is independent of the media used. 1H-NMR spectroscopy in SDS micelles or in perfluoro-tert-butanol allows detection of aggregated peptides probably in a ribbon 2(7) type conformation. These conformations became the predominant structure when Gln50 was replaced by Pro50. Interproton-distance restraints derived from NOE measurements have been classified in two groups corresponding to two types of structures: alpha-helix and essentially extended structures. Consecutive CH alpha (i)/ CH alpha (i + 1) NOEs are only compatible with aggregates. Simulated annealing calculation of dimeric structure agrees with phi and psi angles in the beta-sheet and gamma-turn regions. Fluorescence spectroscopy analysis has shown that the indole groups of both peptides penetrate into SDS micelles; both peptides also induce the formation of micelles at very low concentration of SDS (20 microM). Similar interaction was observed with reverse-phase micelles made of bis(2-ethyhexyl) sodium sulfosuccinate and small unilamellar vesicles (SUV) made of a mixture of phosphatidylcholine/phosphatidylserine. 31P-NMR of vesicles (SUV and large unilamellar vesicles) indicated that the addition of pAntp analogues did not affect the size of phosphatidylcholine/phosphatidylserine vesicles. The addition of pAntp analogues to lipidic dispersions modulates lipid polymorphism in different ways depending on the mixtures of acidic lipids.
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Affiliation(s)
- J P Berlose
- Laboratoire de Chimie Organique Biologique, URA CNRS 493, Université P. et M. Curie, Paris, France
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45
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Kondejewski LH, Farmer SW, Wishart DS, Hancock RE, Hodges RS. Gramicidin S is active against both gram-positive and gram-negative bacteria. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1996; 47:460-6. [PMID: 8836773 DOI: 10.1111/j.1399-3011.1996.tb01096.x] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Four linear and four cyclic analogs of gramicidin S (GS) in which D-Phe was replaced with either D-His, D-Ser, D-Tyr or D-Asn have been prepared by solid-phase peptide synthesis and characterized with respect to antibacterial, antifungal and hemolytic activity. Unlike previous reports, GS and a number of cyclic analogs were found to be active against gram-positive as well as gram-negative bacteria. GS showed MICs ranging from 3 to 12.5 micrograms/mL for gram-negative bacteria, compared to MICs of 3 micrograms/mL for gram-positive bacteria. Furthermore, these analogs were also found to exhibit antifungal activity. Unlike the cyclic analogs, all linear analogs were found to be inactive against a wide range of microorganisms tested, and showed low levels of hemolytic activity. The antibacterial activity was found to be highly dependent on the type of assay used, with solution-based assays showing greater activity against gram-negative bacteria than agar-based assays. The GS cyclic analogs were all less toxic than GS itself, with the analog containing the D-Phe to D-Tyr substitution showing the greatest activity of the synthetic analogs. Hemolytic activity in solution against human and sheep red blood cells paralleled antibiotic activity, with those peptides exhibiting greater antibiotic activity generally showing greater hemolytic activity. Membrane destabilization as monitored using the hydrophobic probe N-phenyl-1-naphthylamine was also found to parallel antibacterial and hemolytic activity of cyclic and linear analogs. These results indicate that GS and certain related analogs may have applications as broad-spectrum antibiotics and should be reevaluated for such purposes.
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Affiliation(s)
- L H Kondejewski
- Department of Biochemistry, University of Alberta, Edmonton, Canada
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46
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Aumelas A, Mangoni M, Roumestand C, Chiche L, Despaux E, Grassy G, Calas B, Chavanieu A. Synthesis and solution structure of the antimicrobial peptide protegrin-1. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 237:575-83. [PMID: 8647100 DOI: 10.1111/j.1432-1033.1996.0575p.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Protegrins are members of a family of five Cys-rich, cationic antimicrobial peptides recently isolated from porcine cells. We have synthesised an 18-amino-acid peptide that corresponds to protegrin-1. After Cys oxidation, the peptide has bactericidal activity against gram-positive and gram-negative bacteria, similar to that described for the natural peptide. The solution structure of protegrin-1 was investigated by means of 1H-NMR spectroscopy in water and in (CD3)2SO, with distance-geometry and simulated-annealing calculations. The C6-C15 and C8-C13 disulfide pattern was determined on the basis of NMR-derived constraints. These two parallel disulfide bridges stabilised a beta-sheet structure which comprised two antiparallel strands (residues 5-9 and 12-16) linked by a distorted beta-turn (residues 9-12). The N-terminus and C-terminus were essentially disordered. The distribution of hydrophobic and hydrophilic residues at the peptide surface was found to be a structural feature shared with tachyplesin-1, a related peptide which displays cytolytic activity, and, to a lesser extent, with mammalian defensins. These findings led us to assume that the distribution pattern could be required for the cytolytic activity of these peptides.
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Affiliation(s)
- A Aumelas
- Centre de Biochimie Structurale, UMR C9955, U414 INSERM, Faculté de Pharmacie, Montpellier, France
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47
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Matsuzaki K, Sugishita K, Fujii N, Miyajima K. Molecular basis for membrane selectivity of an antimicrobial peptide, magainin 2. Biochemistry 1995; 34:3423-9. [PMID: 7533538 DOI: 10.1021/bi00010a034] [Citation(s) in RCA: 330] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Magainin peptides, isolated from Xenopus skin, kill bacteria by permeabilizing their cell membranes whereas they do not lyse erythrocytes. To elucidate the rationale for this membrane selectivity, we compared the effects of the membrane lipid composition and the transmembrane potential on the membrane-lytic power of magainin 2 with that of hemolytic melittin. The activity of magainin to zwitterionic phospholipids constituting the erythrocyte surface was extremely weak compared with that of melittin, and acidic phospholipids are necessary for effective action. The presence of sterols reduced the susceptibility of the membrane to magainin. The generation of an inside-negative transmembrane potential enhanced magainin-induced hemolysis. We can conclude that the absence of any acidic phospholipids on the outer monolayer and the abundant presence of cholesterol, combined with the lack of the transmembrane potential, contribute to the protection of erythrocytes from magainin's attack.
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Affiliation(s)
- K Matsuzaki
- Faculty of Pharmaceutical Sciences, Kyoto University, Japan
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48
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Abstract
Host defense peptides are widely distributed in nature, being found in species from bacteria to humans. The structures of these peptides from insects, horseshoe crabs, frogs, and mammals are known to have the common features of a net cationic charge due to the presence of multiple Arg and Lys residues and in most cases the ability to form amphipathic structures. These properties are important for the mechanism of action that is thought to be a nonreceptor-mediated interaction with the anionic phospholipids of the target cell followed by incorporation into the membrane and disruption of the membrane structure. Host defense peptides have been shown to have broad spectrum antimicrobial activity, able to kill most strains of bacteria as well as some fungi, protozoa, and in addition, many types of tumor cells. Specificity for pathogenic cells over host cells is thought to be due to the composition of the cell membranes, with an increased proportion of anionic phospholipids making the pathogen more susceptible and the presence of cholesterol making the host membranes more resistant. Structure-activity relationship studies have been performed on insect cecropins and apidaecins, horseshoe crab tachyplesins and polyphemusins, and the frog magainins, CPFs (caerulein precursor fragments) and PGLa. In general, changes that increased the basicity and stabilized the amphipathic structure have increased the antimicrobial activity; however, as the peptides become more hydrophobic the degree of specificity decreases. One magainin-2 analogue, MSI-78, has been developed by Magainin Pharmaceuticals as a topical antiinfective and is presently in clinical trials for the treatment of infected diabetic foot ulcers.
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Affiliation(s)
- W L Maloy
- Magainin Pharmaceuticals, Inc., Plymouth Meeting, Pennsylvania 19462
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49
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Saberwal G, Nagaraj R. Cell-lytic and antibacterial peptides that act by perturbing the barrier function of membranes: facets of their conformational features, structure-function correlations and membrane-perturbing abilities. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1197:109-31. [PMID: 8031824 DOI: 10.1016/0304-4157(94)90002-7] [Citation(s) in RCA: 201] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Almost all hemolytic and antimicrobial peptides form part of the defense mechanism of species widely distributed across the evolutionary scale. Although these peptides are of varying lengths and composition, they form amphiphilic structures in a hydrophobic environment. They also have the ability to form channels in natural and model membranes. Hemolytic peptides have proven to be very useful in studying the mechanism of hemolysis and the permeability properties of red blood cells. Preliminary investigations indicate that these peptides may also be useful in the investigation of complex cellular phenomena like exocytosis and neurotransmission. Although molecules like vancomycin, bacitracin and penicillins have been extensively used as antibiotics for therapeutic purposes, most species throughout the evolutionary scale use peptides as antimicrobial agents. These peptides exert their activity by altering the permeability properties of the bacterial plasma membrane and do not interfere with macro molecular synthesis like the other antibiotics that are presently used in therapies. Hence it is likely that resistance to peptide antibacterial agents may not develop easily. Since the problem of antibiotic resistance is presently a particularly severe one, peptide antibiotics may be the drugs of choice in the future.
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Affiliation(s)
- G Saberwal
- Centre for Cellular and Molecular Biology, Hyderabad, India
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50
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Radermacher SW, Schoop VM, Schluesener HJ. Bactenecin, a leukocytic antimicrobial peptide, is cytotoxic to neuronal and glial cells. J Neurosci Res 1993; 36:657-62. [PMID: 8145294 DOI: 10.1002/jnr.490360606] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Small antimicrobial peptides are abundantly produced by leukocytes. These peptides are active against a broad range of pathogens, notably bacteria, fungi, and enveloped viruses, but hardly anything is known about their physiological and pathophysiological relevance. We observed that bactenecin, a dodecapeptide, is strongly cytotoxic to rat embryonic neurons, fetal rat astrocytes and human glioblastoma cells. This neurotoxicity is unique to bactenecin, as a panel of antibacterial peptides from vertebrates and invertebrates, like defensins, corticostatin, indolicidin, cecropin P1, tachyplesin I, the magainins, or apidaecins did not impair neuronal viability.
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Affiliation(s)
- S W Radermacher
- Institute of Brain Research, University of Tübingen, Federal Republic of Germany
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