51
|
Gabernet G, Müller AT, Hiss JA, Schneider G. Membranolytic anticancer peptides. MEDCHEMCOMM 2016. [DOI: 10.1039/c6md00376a] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Understanding the structure–activity relationships and mechanisms of action of membranolytic anticancer peptides could help them advance to therapeutic success.
Collapse
Affiliation(s)
- G. Gabernet
- Department of Chemistry and Applied Biosciences
- Swiss Federal Institute of Technology (ETH)
- CH-8093 Zurich
- Switzerland
| | - A. T. Müller
- Department of Chemistry and Applied Biosciences
- Swiss Federal Institute of Technology (ETH)
- CH-8093 Zurich
- Switzerland
| | - J. A. Hiss
- Department of Chemistry and Applied Biosciences
- Swiss Federal Institute of Technology (ETH)
- CH-8093 Zurich
- Switzerland
| | - G. Schneider
- Department of Chemistry and Applied Biosciences
- Swiss Federal Institute of Technology (ETH)
- CH-8093 Zurich
- Switzerland
| |
Collapse
|
52
|
Shahmiri M, Enciso M, Mechler A. Controls and constrains of the membrane disrupting action of Aurein 1.2. Sci Rep 2015; 5:16378. [PMID: 26574052 PMCID: PMC4648102 DOI: 10.1038/srep16378] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 10/13/2015] [Indexed: 11/21/2022] Open
Abstract
Aurein 1.2 is a 13 residue antimicrobial peptide secreted by the Australian tree frog Litoria Aurea. It is a surface-acting membrane disrupting peptide that permeabilizes bacterial membranes via the carpet mechanism; the molecular details of this process are mostly unknown. Here the mechanism of action of Aurein 1.2 was investigated with an emphasis on the role of membrane charge and C-terminal amidation of the peptide. Using quartz crystal microbalance (QCM) fingerprinting it was found that the membrane charge correlates with membrane affinity of the peptide, however the binding and the membrane disrupting processes are not charge driven; increased membrane charge reduces the membrane disrupting activity. Coarse grain simulations revealed that phenylalanine residues act as membrane anchors. Accordingly Aurein 1.2 has the ability to bind to any membrane. Furthermore, bundling precludes membrane disruption in case of wild type peptides, while non C-terminal amidated peptides form random aggregates leading to detachment from the membrane. Hence C-terminal amidation is crucial for Aurein 1.2 action. Our results suggest that Aurein 1.2 acts via aggregation driven membrane penetration. The concomitant change in the tension of the outer leaflet imposes a spontaneous curvature on the membrane, leading to disintegration.
Collapse
Affiliation(s)
- Mahdi Shahmiri
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora Vic 3086, Australia
| | - Marta Enciso
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora Vic 3086, Australia
| | - Adam Mechler
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora Vic 3086, Australia
| |
Collapse
|
53
|
Inhibitory Effects of Antimicrobial Peptides on Lipopolysaccharide-Induced Inflammation. Mediators Inflamm 2015; 2015:167572. [PMID: 26612970 PMCID: PMC4647054 DOI: 10.1155/2015/167572] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/17/2015] [Accepted: 08/25/2015] [Indexed: 01/08/2023] Open
Abstract
Antimicrobial peptides (AMPs) are usually small molecule peptides, which display broad-spectrum antimicrobial activity, high efficiency, and stability. For the multiple-antibiotic-resistant strains, AMPs play a significant role in the development of novel antibiotics because of their broad-spectrum antimicrobial activities and specific antimicrobial mechanism. Besides broad-spectrum antibacterial activity, AMPs also have anti-inflammatory activity. The neutralization of lipopolysaccharides (LPS) plays a key role in anti-inflammatory action of AMPs. On the one hand, AMPs can readily penetrate the cell wall barrier by neutralizing LPS to remove Gram-negative bacteria that can lead to infection. On the contrary, AMPs can also inhibit the production of biological inflammatory cytokines to reduce the inflammatory response through neutralizing circulating LPS. In addition, AMPs also modulate the host immune system by chemotaxis of leukocytes, to promote immune cell proliferation, epithelialization, and angiogenesis and thus play a protective role. This review summarizes some recent researches about anti-inflammatory AMPs, with a focus on the interaction of AMPs and LPS on the past decade.
Collapse
|
54
|
Gill EE, Franco OL, Hancock REW. Antibiotic adjuvants: diverse strategies for controlling drug-resistant pathogens. Chem Biol Drug Des 2015; 85:56-78. [PMID: 25393203 PMCID: PMC4279029 DOI: 10.1111/cbdd.12478] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/31/2014] [Accepted: 11/03/2014] [Indexed: 01/08/2023]
Abstract
The growing number of bacterial pathogens that are resistant to numerous antibiotics is a cause for concern around the globe. There have been no new broad-spectrum antibiotics developed in the last 40 years, and the drugs we have currently are quickly becoming ineffective. In this article, we explore a range of therapeutic strategies that could be employed in conjunction with antibiotics and may help to prolong the life span of these life-saving drugs. Discussed topics include antiresistance drugs, which are administered to potentiate the effects of current antimicrobials in bacteria where they are no longer (or never were) effective; antivirulence drugs, which are directed against bacterial virulence factors; host-directed therapies, which modulate the host's immune system to facilitate infection clearance; and alternative treatments, which include such therapies as oral rehydration for diarrhea, phage therapy, and probiotics. All of these avenues show promise for the treatment of bacterial infections and should be further investigated to explore their full potential in the face of a postantibiotic era.
Collapse
Affiliation(s)
- Erin E Gill
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | | | | |
Collapse
|
55
|
Kim YM, Kim NH, Lee JW, Jang JS, Park YH, Park SC, Jang MK. Novel chimeric peptide with enhanced cell specificity and anti-inflammatory activity. Biochem Biophys Res Commun 2015; 463:322-8. [PMID: 26028561 DOI: 10.1016/j.bbrc.2015.05.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 05/15/2015] [Indexed: 01/22/2023]
Abstract
An antimicrobial peptide (AMP), Hn-Mc, was designed by combining the N-terminus of HPA3NT3 and the C-terminus of melittin. This chimeric AMP exhibited potent antibacterial activity with low minimal inhibitory concentrations (MICs), ranging from 1 to 2 μM against four drug-susceptible bacteria and ten drug-resistant bacteria. Moreover, the hemolysis and cytotoxicity was reduced significantly compared to those of the parent peptides, highlighting its high cell selectivity. The morphological changes in the giant unilamellar vesicles and bacterial cell surfaces caused by the Hn-Mc peptide suggested that it killed the microbial cells by damaging the membrane envelope. An in vivo study also demonstrated the antibacterial activity of the Hn-Mc peptide in a mouse model infected with drug-resistant bacteria. In addition, the chimeric peptide inhibited the expression of lipopolysaccharide (LPS)-induced cytokines in RAW 264.7 cells by preventing the interaction between LPS and Toll-like receptors. These results suggest that this chimeric peptide is an antimicrobial and anti-inflammatory candidate as a pharmaceutic agent.
Collapse
Affiliation(s)
- Young-Min Kim
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea
| | - Nam-Hong Kim
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea
| | - Jong-Wan Lee
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea
| | - Jin-Sun Jang
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea
| | - Yung-Hoon Park
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea
| | - Seong-Cheol Park
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea.
| | - Mi-Kyeong Jang
- Department of Polymer Science and Engineering, College of Engineering, Sunchon National University, Suncheon, Jeonnam 540-950, South Korea.
| |
Collapse
|
56
|
Uppu DSSM, Ghosh C, Haldar J. Surviving sepsis in the era of antibiotic resistance: are there any alternative approaches to antibiotic therapy? Microb Pathog 2015; 80:7-13. [PMID: 25677832 DOI: 10.1016/j.micpath.2015.02.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/04/2015] [Accepted: 02/06/2015] [Indexed: 01/25/2023]
Abstract
Sepsis, a serious cause of morbidity in humans, has no proper single medication dedicated to it. In this review, we look at the current treatment modalities, the different approaches attempted towards treating it and alternative approaches that could be implemented to counter this neglected disease condition. The use of antibiotics towards treatment of sepsis, use of combinations and strategies derived from natural antimicrobial peptides have been dealt in detail. The social and technical difficulties associated with treating sepsis and the possible ways of combating them have also been discussed.
Collapse
Affiliation(s)
- Divakara S S M Uppu
- Chemical Biology and Medicinal Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
| | - Chandradhish Ghosh
- Chemical Biology and Medicinal Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
| | - Jayanta Haldar
- Chemical Biology and Medicinal Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India.
| |
Collapse
|
57
|
He J, Starr CG, Wimley WC. A lack of synergy between membrane-permeabilizing cationic antimicrobial peptides and conventional antibiotics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:8-15. [PMID: 25268681 DOI: 10.1016/j.bbamem.2014.09.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 09/16/2014] [Accepted: 09/20/2014] [Indexed: 01/20/2023]
Abstract
The rapid rise in morbidity and mortality from drug-resistant pathogenic bacteria has generated elevated interest in combination therapy using antimicrobial agents. Antimicrobial peptides (AMPs) are a candidate drug class to advance the development of combination therapies. Although the literature is ambiguous, the generic membrane disrupting activity of AMPs could enable them to synergize with conventional small molecule antibiotics by increasing access to the cell and by triggering membrane damage mediators. We used a novel assay to measure interactions, expressed as fractional inhibitory concentration (FIC), between four conventional antibiotics in combination with four well-characterized, membrane permeabilizing AMPs, against three species of Gram negative and Gram positive bacteria, giving 40 total pair-wise measurements of FIC with statistical uncertainties. We chose a set of AMPs that are known to dramatically disrupt the membranes of both Gram negative and Gram positive bacteria. Yet none of the membrane permeabilizing antimicrobial peptides interacted synergistically with any of the conventional antibiotic drugs in any organism. Large-scale membrane disruption and permeabilization by AMPs is not sufficient to drive them to act synergistically with chemical antibiotics in either Gram negative or Gram positive microbes.
Collapse
Affiliation(s)
- Jing He
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Charles G Starr
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - William C Wimley
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA.
| |
Collapse
|
58
|
Wang Z, Zhang L, Wang J, Wei D, Shi B, Shan A. Synergistic interaction of PMAP-36 and PRW4 with aminoglycoside antibiotics and their antibacterial mechanism. World J Microbiol Biotechnol 2014; 30:3121-8. [DOI: 10.1007/s11274-014-1739-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 09/10/2014] [Indexed: 10/24/2022]
|
59
|
Bedran TBL, Mayer MPA, Spolidorio DP, Grenier D. Synergistic anti-inflammatory activity of the antimicrobial peptides human beta-defensin-3 (hBD-3) and cathelicidin (LL-37) in a three-dimensional co-culture model of gingival epithelial cells and fibroblasts. PLoS One 2014; 9:e106766. [PMID: 25187958 PMCID: PMC4154759 DOI: 10.1371/journal.pone.0106766] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 08/05/2014] [Indexed: 11/19/2022] Open
Abstract
Given the spread of antibiotic resistance in bacterial pathogens, antimicrobial peptides that can also modulate the immune response may be a novel approach for effectively controlling periodontal infections. In the present study, we used a three-dimensional (3D) co-culture model of gingival epithelial cells and fibroblasts stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS) to investigate the anti-inflammatory properties of human beta-defensin-3 (hBD-3) and cathelicidin (LL-37) and to determine whether these antimicrobial peptides can act in synergy. The 3D co-culture model composed of gingival fibroblasts embedded in a collagen matrix overlaid with gingival epithelial cells had a synergistic effect with respect to the secretion of IL-6 and IL-8 in response to LPS stimulation compared to fibroblasts and epithelial cells alone. The 3D co-culture model was stimulated with non-cytotoxic concentrations of hBD-3 (10 and 20 µM) and LL-37 (0.1 and 0.2 µM) individually and in combination in the presence of A. actinomycetemcomitans LPS. A multiplex ELISA assay was used to quantify the secretion of 41 different cytokines. hBD-3 and LL-37 acted in synergy to reduce the secretion of GRO-alpha, G-CSF, IP-10, IL-6, and MCP-1, but only had an additive effect on reducing the secretion of IL-8 in response to A. actinomycetemcomitans LPS stimulation. The present study showed that hBD-3 acted in synergy with LL-37 to reduce the secretion of cytokines by an LPS-stimulated 3D model of gingival mucosa. This combination of antimicrobial peptides thus shows promising potential as an adjunctive therapy for treating inflammatory periodontitis.
Collapse
Affiliation(s)
- Telma Blanca Lombardo Bedran
- Department of Oral Diagnosis and Surgery, Araraquara Dental School, State University of São Paulo, São Paulo, Brazil
| | - Márcia Pinto Alves Mayer
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Denise Palomari Spolidorio
- Department of Physiology and Pathology, Araraquara Dental School, State University of São Paulo, São Paulo, Brazil
| | - Daniel Grenier
- Oral Ecology Research Group, Faculty of Dentistry, Université Laval, Quebec City, QC, Canada
| |
Collapse
|
60
|
Dua HS, Otri AM, Hopkinson A, Mohammed I. In vitro studies on the antimicrobial peptide human beta-defensin 9 (HBD9): signalling pathways and pathogen-related response (an American Ophthalmological Society thesis). TRANSACTIONS OF THE AMERICAN OPHTHALMOLOGICAL SOCIETY 2014; 112:50-73. [PMID: 25646028 PMCID: PMC4311673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE Human β-defensins (HBDs) are an important part of the innate immune host defense at the ocular surface. Unlike other defensins, expression of HBD9 at the ocular surface is reduced during microbial infection, but activation of toll-like receptor 2 (TLR2) in corneal epithelial cells has been shown to up-regulate HBD9. Our purpose was to test the hypothesis that TLR2 has a key role in the signalling pathway(s) involved in the overexpression or underexpression of HBD9, and accordingly, different pathogens would induce a different expression pattern of HBD9. METHODS The in vitro RNAi silencing method and response to dexamethasone were used to determine key molecules involved in signalling pathways of HBD9 in immortalized human corneal epithelial cells. The techniques included cell culture with exposure to specific transcription factor inhibitors and bacteria, RNA extraction and cDNA synthesis, quantitative real-time polymerase chain reaction, and immunohistology. RESULTS This study demonstrates that TLR2 induces HBD9 mRNA and protein expression in a time- and dose-dependent manner. Transforming growth factor-β-activated kinase 1 (TAK1) plays a central role in HBD9 induction by TLR2, and transcription factors c-JUN and activating transcription factor 2 are also involved. Dexamethasone reduces TLR2-mediated up-regulation of HBD9 mRNA and protein levels in mitogen-activated protein kinase phosphatase 1 (MKP1)-dependent and c-JUN-independent manner. HBD9 expression differs with gram-negative and gram-positive bacteria. CONCLUSIONS TLR2-mediated MKPs and nuclear factor-κB signalling pathways are involved in HBD9 expression. TAK-1 is a key molecule. These molecules can be potentially targeted to modulate HBD9 expression. Differential expression of HBD9 with different bacteria could be related to differences in pathogen-associated molecular patterns of these organisms.
Collapse
Affiliation(s)
- Harminder S Dua
- Academic Department of Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, England
| | - Ahmad Muneer Otri
- Academic Department of Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, England
| | - Andrew Hopkinson
- Academic Department of Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, England
| | - Imran Mohammed
- Academic Department of Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, England
| |
Collapse
|
61
|
Ryder MP, Wu X, McKelvey GR, McGuire J, Schilke KF. Binding interactions of bacterial lipopolysaccharide and the cationic amphiphilic peptides polymyxin B and WLBU2. Colloids Surf B Biointerfaces 2014; 120:81-7. [PMID: 24905681 DOI: 10.1016/j.colsurfb.2014.05.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 05/01/2014] [Accepted: 05/02/2014] [Indexed: 11/26/2022]
Abstract
Passage of blood through a sorbent device for removal of bacteria and endotoxin by specific binding with immobilized, membrane-active, bactericidal peptides holds promise for treating severe blood infections. Peptide insertion in the target membrane and rapid/strong binding is desirable, while membrane disruption and release of degradation products to the circulating blood is not. Here we describe interactions between bacterial endotoxin (lipopolysaccharide, LPS) and the membrane-active, bactericidal peptides WLBU2 and polymyxin B (PmB). Analysis of the interfacial behavior of mixtures of LPS and peptide using air-water interfacial tensiometry and optical waveguide lightmode spectroscopy strongly suggests insertion of intact LPS vesicles by the peptide WLBU2 without vesicle destabilization. In contrast, dynamic light scattering (DLS) studies show that LPS vesicles appear to undergo peptide-induced destabilization in the presence of PmB. Circular dichroism spectra further confirm that WLBU2, which shows disordered structure in aqueous solution and substantially helical structure in membrane-mimetic environments, is stably located within the LPS membrane in peptide-vesicle mixtures. We therefore expect that presentation of WLBU2 at an interface, if tethered in a fashion which preserves its mobility and solvent accessibility, will enable the capture of bacteria and endotoxin without promoting reintroduction of endotoxin to the circulating blood, thus minimizing adverse clinical outcomes. On the other hand, our results suggest no such favorable outcome of LPS interactions with polymyxin B.
Collapse
Affiliation(s)
- Matthew P Ryder
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, United States
| | - Xiangming Wu
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, United States
| | - Greg R McKelvey
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, United States
| | - Joseph McGuire
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, United States
| | - Karl F Schilke
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, United States.
| |
Collapse
|
62
|
Potential of host defense peptide prodrugs as neutrophil elastase-dependent anti-infective agents for cystic fibrosis. Antimicrob Agents Chemother 2013; 58:978-85. [PMID: 24277028 DOI: 10.1128/aac.01167-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Host defense peptides (HDPs) are short antimicrobial peptides of the innate immune system. Deficiencies in HDPs contribute to enhanced susceptibility to infections, e.g., in cystic fibrosis (CF). Exogenous HDPs can compensate for these deficiencies, but their development as antimicrobials is limited by cytotoxicity. Three HDP prodrugs were designed so their net positive charge is masked by a promoiety containing a substrate for the enzyme neutrophil elastase (NE). This approach can confine activation to sites with high NE levels. Enzyme-labile peptides were synthesized, and their activation was investigated using purified NE. Susceptibilities of Pseudomonas aeruginosa to parent and prodrug peptides in the presence and absence of NE-rich CF human bronchoalveolar lavage (BAL) fluid and different NaCl concentrations were compared. The effect of the HDP promoiety on cytotoxicity was determined with cystic fibrosis bronchial epithelial (CFBE41o-) cells. NE in CF BAL fluids activated the HDP prodrugs, restoring bactericidal activity against reference and clinical isolates of P. aeruginosa. However, activation also required the addition of 300 mM NaCl. Under these conditions, the bactericidal activity levels of the HDP prodrugs differed, with pro-P18 demonstrating the greatest activity (90% to 100% of that of the parent, P18, at 6.25 μg/ml). Cytotoxic effects on CFBE41o- cells were reduced by the addition of the promoiety to HDPs. We demonstrate here for the first time the selective activation of novel HDP prodrugs by a host disease-associated enzyme at in vivo concentrations of the CF lung. This approach may lead to the development of novel therapeutic agents with low toxicity that are active under the challenging conditions of the CF lung.
Collapse
|
63
|
Antimicrobial lactoferrin peptides: the hidden players in the protective function of a multifunctional protein. INTERNATIONAL JOURNAL OF PEPTIDES 2013; 2013:390230. [PMID: 23554820 PMCID: PMC3608178 DOI: 10.1155/2013/390230] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Accepted: 01/22/2013] [Indexed: 11/17/2022]
Abstract
Lactoferrin is a multifunctional, iron-binding glycoprotein which displays a wide array of modes of action to execute its primary antimicrobial function. It contains various antimicrobial peptides which are released upon its hydrolysis by proteases. These peptides display a similarity with the antimicrobial cationic peptides found in nature. In the current scenario of increasing resistance to antibiotics, there is a need for the discovery of novel antimicrobial drugs. In this context, the structural and functional perspectives on some of the antimicrobial peptides found in N-lobe of lactoferrin have been reviewed. This paper provides the comparison of lactoferrin peptides with other antimicrobial peptides found in nature as well as interspecies comparison of the structural properties of these peptides within the native lactoferrin.
Collapse
|
64
|
Adaptive and mutational resistance: role of porins and efflux pumps in drug resistance. Clin Microbiol Rev 2013; 25:661-81. [PMID: 23034325 DOI: 10.1128/cmr.00043-12] [Citation(s) in RCA: 527] [Impact Index Per Article: 47.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The substantial use of antibiotics in the clinic, combined with a dearth of new antibiotic classes, has led to a gradual increase in the resistance of bacterial pathogens to these compounds. Among the various mechanisms by which bacteria endure the action of antibiotics, those affecting influx and efflux are of particular importance, as they limit the interaction of the drug with its intracellular targets and, consequently, its deleterious effects on the cell. This review evaluates the impact of porins and efflux pumps on two major types of resistance, namely, mutational and adaptive types of resistance, both of which are regarded as key phenomena in the global rise of antibiotic resistance among pathogenic microorganisms. In particular, we explain how adaptive and mutational events can dramatically influence the outcome of antibiotic therapy by altering the mechanisms of influx and efflux of antibiotics. The identification of porins and pumps as major resistance markers has opened new possibilities for the development of novel therapeutic strategies directed specifically against these mechanisms.
Collapse
|
65
|
Identification of synthetic host defense peptide mimics that exert dual antimicrobial and anti-inflammatory activities. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1784-91. [PMID: 22956655 DOI: 10.1128/cvi.00291-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A group of synthetic antimicrobial oligomers, inspired by naturally occurring antimicrobial peptides, were analyzed for the ability to modulate innate immune responses to Toll-like receptor (TLR) ligands. These synthetic mimics of antimicrobial peptides (SMAMPs) specifically reduced cytokine production in response to Staphylococcus aureus and the S. aureus component lipoteichoic acid (LTA), a TLR2 agonist. Anti-inflammatory SMAMPs prevented the induction of tumor necrosis factor (TNF), interleukin 6 (IL-6), and IL-10 in response to S. aureus or LTA, but no other TLR2 ligands. We show that these SMAMPs bind specifically to LTA in vitro and prevent its interaction with TLR2. Importantly, the SMAMP greatly reduced the induction of TNF and IL-6 in vivo in mice acutely infected with S. aureus while simultaneously reducing bacterial loads dramatically (4 log(10)). Thus, these SMAMPs can eliminate the damage induced by pathogen-associated molecular patterns (PAMPs) while simultaneously eliminating infection in vivo. They are the first known SMAMPs to demonstrate anti-inflammatory and antibacterial activities in vivo.
Collapse
|
66
|
Teixeira V, Feio MJ, Bastos M. Role of lipids in the interaction of antimicrobial peptides with membranes. Prog Lipid Res 2012; 51:149-77. [DOI: 10.1016/j.plipres.2011.12.005] [Citation(s) in RCA: 461] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
67
|
The Design and Construction of K11: A Novel α-Helical Antimicrobial Peptide. Int J Microbiol 2012; 2012:764834. [PMID: 22518150 PMCID: PMC3299254 DOI: 10.1155/2012/764834] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 10/20/2011] [Accepted: 12/05/2011] [Indexed: 01/08/2023] Open
Abstract
Amphipathic α-helical antimicrobial peptides comprise a class of broad-spectrum agents that are used against pathogens. We designed a series of antimicrobial peptides, CP-P (KWKSFIKKLTSKFLHLAKKF) and its derivatives, and determined their minimum inhibitory concentrations (MICs) against Pseudomonas aeruginosa, their minimum hemolytic concentrations (MHCs) for human erythrocytes, and the Therapeutic Index (MHC/MIC ratio). We selected the derivative peptide K11, which had the highest therapeutic index (320) among the tested peptides, to determine the MICs against Gram-positive and Gram-negative bacteria and 22 clinical isolates including Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Klebsiella pneumonia. K11 exhibited low MICs (less than 10 μg/mL) and broad-spectrum antimicrobial activity, especially against clinically isolated drug-resistant pathogens. Therefore, these results indicate that K11 is a promising candidate antimicrobial peptide for further studies.
Collapse
|
68
|
Montesinos E, Badosa E, Cabrefiga J, Planas M, Feliu L, Bardají E. Antimicrobial Peptides for Plant Disease Control. From Discovery to Application. ACS SYMPOSIUM SERIES 2012. [DOI: 10.1021/bk-2012-1095.ch012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Affiliation(s)
- Emilio Montesinos
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, 17071 Girona, Spain
- LIPPSO, Department of Chemistry; University of Girona, Campus Montilivi, 17071 Girona, Spain
| | - Esther Badosa
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, 17071 Girona, Spain
- LIPPSO, Department of Chemistry; University of Girona, Campus Montilivi, 17071 Girona, Spain
| | - Jordi Cabrefiga
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, 17071 Girona, Spain
- LIPPSO, Department of Chemistry; University of Girona, Campus Montilivi, 17071 Girona, Spain
| | - Marta Planas
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, 17071 Girona, Spain
- LIPPSO, Department of Chemistry; University of Girona, Campus Montilivi, 17071 Girona, Spain
| | - Lidia Feliu
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, 17071 Girona, Spain
- LIPPSO, Department of Chemistry; University of Girona, Campus Montilivi, 17071 Girona, Spain
| | - Eduard Bardají
- Laboratory of Plant Pathology, Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, 17071 Girona, Spain
- LIPPSO, Department of Chemistry; University of Girona, Campus Montilivi, 17071 Girona, Spain
| |
Collapse
|
69
|
The role of antimicrobial peptides in preventing multidrug-resistant bacterial infections and biofilm formation. Int J Mol Sci 2011; 12:5971-92. [PMID: 22016639 PMCID: PMC3189763 DOI: 10.3390/ijms12095971] [Citation(s) in RCA: 193] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 09/05/2011] [Accepted: 09/06/2011] [Indexed: 01/21/2023] Open
Abstract
Over the last decade, decreasing effectiveness of conventional antimicrobial-drugs has caused serious problems due to the rapid emergence of multidrug-resistant pathogens. Furthermore, biofilms, which are microbial communities that cause serious chronic infections and dental plaque, form environments that enhance antimicrobial resistance. As a result, there is a continuous search to overcome or control such problems, which has resulted in antimicrobial peptides being considered as an alternative to conventional drugs. Antimicrobial peptides are ancient host defense effector molecules in living organisms. These peptides have been identified in diverse organisms and synthetically developed by using peptidomimic techniques. This review was conducted to demonstrate the mode of action by which antimicrobial peptides combat multidrug-resistant bacteria and prevent biofilm formation and to introduce clinical uses of these compounds for chronic disease, medical devices, and oral health. In addition, combinations of antimicrobial peptides and conventional drugs were considered due to their synergetic effects and low cost for therapeutic treatment.
Collapse
|
70
|
Suzuki MM, Matsumoto M, Yamamoto A, Ochiai M, Horiuchi Y, Niwa M, Omi H, Kobayashi T, Takagi T. Molecular design of LPS-binding peptides. J Microbiol Methods 2010; 83:153-5. [DOI: 10.1016/j.mimet.2010.08.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 07/30/2010] [Accepted: 08/09/2010] [Indexed: 11/24/2022]
|
71
|
Structural features governing the activity of lactoferricin-derived peptides that act in synergy with antibiotics against Pseudomonas aeruginosa in vitro and in vivo. Antimicrob Agents Chemother 2010; 55:218-28. [PMID: 20956602 DOI: 10.1128/aac.00904-10] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is naturally resistant to many antibiotics, and infections caused by this organism are a serious threat, especially to hospitalized patients. The intrinsic low permeability of P. aeruginosa to antibiotics results from the coordinated action of several mechanisms, such as the presence of restrictive porins and the expression of multidrug efflux pump systems. Our goal was to develop antimicrobial peptides with an improved bacterial membrane-permeabilizing ability, so that they enhance the antibacterial activity of antibiotics. We carried out a structure activity relationship analysis to investigate the parameters that govern the permeabilizing activity of short (8- to 12-amino-acid) lactoferricin-derived peptides. We used a new class of constitutional and sequence-dependent descriptors called PEDES (peptide descriptors from sequence) that allowed us to predict (Spearman's ρ = 0.74; P < 0.001) the permeabilizing activity of a new peptide generation. To study if peptide-mediated permeabilization could neutralize antibiotic resistance mechanisms, the most potent peptides were combined with antibiotics, and the antimicrobial activities of the combinations were determined on P. aeruginosa strains whose mechanisms of resistance to those antibiotics had been previously characterized. A subinhibitory concentration of compound P2-15 or P2-27 sensitized P. aeruginosa to most classes of antibiotics tested and counteracted several mechanisms of antibiotic resistance, including loss of the OprD porin and overexpression of several multidrug efflux pump systems. Using a mouse model of lethal infection, we demonstrated that whereas P2-15 and erythromycin were unable to protect mice when administered separately, concomitant administration of the compounds afforded long-lasting protection to one-third of the animals.
Collapse
|
72
|
Kim JY, Park SC, Yoon MY, Hahm KS, Park Y. C-terminal amidation of PMAP-23: translocation to the inner membrane of Gram-negative bacteria. Amino Acids 2010; 40:183-95. [PMID: 20512598 DOI: 10.1007/s00726-010-0632-1] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 04/21/2010] [Indexed: 01/09/2023]
Abstract
PMAP-23 is a member of the cathelicidin family derived from pig myeloid cells and has potent antimicrobial activity. Amidation of the carboxyl terminus (C-terminus) of an antimicrobial peptide generally enhances its structural stability and antimicrobial activity or decreases its cytotoxicity. The aim of the present study was to investigate the effect of amidation on the mode of action in PMAP-23. Irrespective of amidation, PMAP-23 adopts a helix-hinge-helix structure in a membrane-mimetic environment. The antibacterial activities of PMAP-23C, which had a free C-terminus, and PMAP-23N, which had an amidated C-terminus, were similar against Gram-negative bacteria, reflecting a similar ability to neutralize lipopolysaccharide. However, PMAP-23N assumed a perpendicular orientation across the outer to the inner leaflet of the bacterial inner membrane, while PMAP-23C was orientated parallel to the lipid bilayer, as determined by following the blue shift in tryptophan fluorescence, as well as calcein release from liposomes and SYTOX Green uptake assays. These results suggest that N-terminal amidation of PMAP-23 provides structural stability and increases the peptide's cationic charge, facilitating translocation into the bacterial inner membrane.
Collapse
Affiliation(s)
- Jin-Young Kim
- Research Center for Proteineous Materials (RCPM), Chosun University, Kwangju, Korea
| | | | | | | | | |
Collapse
|
73
|
Gustafsson A, Olin AI, Ljunggren L. LPS interactions with immobilized and soluble antimicrobial peptides. Scandinavian Journal of Clinical and Laboratory Investigation 2010; 70:194-200. [DOI: 10.3109/00365511003663622] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Anna Gustafsson
- Department of Biomedical Laboratory Science, Malmö University, Malmö, Sweden
| | - Anders I. Olin
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Lennart Ljunggren
- Department of Biomedical Laboratory Science, Malmö University, Malmö, Sweden
| |
Collapse
|
74
|
Rosenfeld Y, Lev N, Shai Y. Effect of the Hydrophobicity to Net Positive Charge Ratio on Antibacterial and Anti-Endotoxin Activities of Structurally Similar Antimicrobial Peptides. Biochemistry 2010; 49:853-61. [DOI: 10.1021/bi900724x] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yosef Rosenfeld
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Naama Lev
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yechiel Shai
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
75
|
Wu G, Fan X, Li L, Wang H, Ding J, Hongbin W, Zhao R, Gou L, Shen Z, Xi T. Interaction of antimicrobial peptide s-thanatin with lipopolysaccharide in vitro and in an experimental mouse model of septic shock caused by a multidrug-resistant clinical isolate of Escherichia coli. Int J Antimicrob Agents 2009; 35:250-4. [PMID: 20045294 DOI: 10.1016/j.ijantimicag.2009.11.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 11/09/2009] [Accepted: 11/16/2009] [Indexed: 10/20/2022]
Abstract
s-thanatin, an analogue of thanatin, was synthesised by substituting the fifteenth amino acid threonine with serine and showed broad antimicrobial activity against Gram-negative and Gram-positive bacteria. To evaluate its antimicrobial activity against a multidrug-resistant (MDR) clinical isolate as well as its anti-endotoxin activity, its lipopolysaccharide (LPS)-binding and -neutralising activity in vitro and its therapeutic efficacy in an experimental model of septic shock caused by a MDR clinical isolate of Escherichia coli were studied. The ability of s-thanatin to bind or neutralise LPS from E. coli O111:B4 was determined using a quantitative assay kit. Male ICR mice were given an intraperitoneal (i.p.) administration of 2x10(10) colony-forming units of E. coli E79466. Following bacterial challenge, all animals were randomised to receive i.p. administration of saline, 40mg/kg ceftazidime (CAZ), or 40mg/kg CAZ+s-thanatin (10, 20 or 40mg/kg). The results showed that s-thanatin not only completely bound to the LPS (median effective concentration of 17.5microg/mL) but also improved the survival and reduced the number of inoculated bacteria in a mouse model of septic shock. s-thanatin may be an attractive candidate to develop as an anti-MDR bacterial agent.
Collapse
Affiliation(s)
- Guoqiu Wu
- Center of Clinical Laboratory Medicine of Zhongda Hospital, Southeast University, 87 Dingjiaqiao, Nanjing 210009, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
76
|
Diamond G, Beckloff N, Weinberg A, Kisich KO. The roles of antimicrobial peptides in innate host defense. Curr Pharm Des 2009; 15:2377-92. [PMID: 19601838 DOI: 10.2174/138161209788682325] [Citation(s) in RCA: 415] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Antimicrobial peptides (AMPs) are multi-functional peptides whose fundamental biological role in vivo has been proposed to be the elimination of pathogenic microorganisms, including Gram-positive and -negative bacteria, fungi, and viruses. Genes encoding these peptides are expressed in a variety of cells in the host, including circulating phagocytic cells and mucosal epithelial cells, demonstrating a wide range of utility in the innate immune system. Expression of these genes is tightly regulated; they are induced by pathogens and cytokines as part of the host defense response, and they can be suppressed by bacterial virulence factors and environmental factors which can lead to increased susceptibility to infection. New research has also cast light on alternative functionalities, including immunomodulatory activities, which are related to their unique structural characteristics. These peptides represent not only an important component of innate host defense against microbial colonization and a link between innate and adaptive immunity, but also form a foundation for the development of new therapeutic agents.
Collapse
Affiliation(s)
- Gill Diamond
- Department of Oral Biology, UMDNJ-New Jersey Dental School, Newark, NJ 07101, USA.
| | | | | | | |
Collapse
|
77
|
Temporins and their synergism against Gram-negative bacteria and in lipopolysaccharide detoxification. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:1610-9. [DOI: 10.1016/j.bbamem.2009.04.021] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Revised: 03/13/2009] [Accepted: 04/28/2009] [Indexed: 11/21/2022]
|
78
|
Rathinakumar R, Walkenhorst WF, Wimley WC. Broad-spectrum antimicrobial peptides by rational combinatorial design and high-throughput screening: the importance of interfacial activity. J Am Chem Soc 2009; 131:7609-17. [PMID: 19445503 PMCID: PMC2935846 DOI: 10.1021/ja8093247] [Citation(s) in RCA: 237] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We recently described 10 peptides selected from a 16,384-member combinatorial library based on their ability to permeabilize synthetic lipid vesicles in vitro. These peptides did not share a common sequence motif, length, or net charge; nonetheless, they shared a mechanism of action that is similar to the natural membrane permeabilizing antimicrobial peptides (AMP). To characterize the selected peptides and to compare the activity of AMPs in vivo and in vitro, we report on the biological activity of the same selected peptides in bacteria, fungi, and mammalian cells. Each of the peptides has sterilizing activity against all classes of microbes tested, at 2-8 microM peptide, with only slight hemolytic or cytotoxicity against mammalian cells. Similar to many natural AMPs, bacteria are killed within a few minutes of peptide addition, and the lethal step in vivo is membrane permeabilization. Single D-amino acid substitutions eliminated or diminished the secondary structure of the peptides, and yet, they retained activity against some microbes. Thus, secondary structure and biological activity are not coupled, consistent with the hypothesis that AMPs do not form pores of well-defined structure in membranes but rather destabilize membranes by partitioning into membrane interfaces and disturbing the organization of the lipids, a property that we have called "interfacial activity". The observation that broad-spectrum activity, but not all antimicrobial activity, is lost by small changes to the peptides suggests that the in vitro screen is specifically selecting for the rare peptides that have broad-spectrum activity. We put forth the hypothesis that methods focusing on screening peptide libraries in vitro for members with the appropriate interfacial activity can enable the design, selection, and discovery of novel, potent, and broad-spectrum membrane-active antibiotics.
Collapse
Affiliation(s)
- Ramesh Rathinakumar
- Department of Biochemistry, Tulane University Health Sciences Center, New Orleans LA, 70112
| | | | - William C. Wimley
- Department of Biochemistry, Tulane University Health Sciences Center, New Orleans LA, 70112
| |
Collapse
|
79
|
Thwaite JE, Humphrey S, Fox MA, Savage VL, Laws TR, Ulaeto DO, Titball RW, Atkins HS. The cationic peptide magainin II is antimicrobial for Burkholderia cepacia-complex strains. J Med Microbiol 2009; 58:923-929. [PMID: 19502364 DOI: 10.1099/jmm.0.008128-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study was undertaken to determine the antibacterial activity of eight cationic antimicrobial peptides towards strains of genomovars I-V of the Burkholderia cepacia complex (Bcc) in time-kill assays. All but one of the peptides failed to show activity against the panel of test strains. The exception was magainin II, a 23 aa peptide isolated from the epidermis of the African clawed frog, Xenopus laevis, which exhibited significant bactericidal activity for Bcc genomovars most frequently associated with lung infection of patients with cystic fibrosis. In vitro studies indicated that magainin II protected a human bronchial epithelial cell line (BEAS-2B) from killing by Bcc and suggest that this peptide may have therapeutic potential against these organisms.
Collapse
Affiliation(s)
- Joanne E Thwaite
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| | - Suzanne Humphrey
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| | - Marc A Fox
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| | - Victoria L Savage
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| | - Thomas R Laws
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| | - David O Ulaeto
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| | - Richard W Titball
- School of Biosciences, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Helen S Atkins
- Defence Science and Technology Laboratory, Porton Down, Salisbury SP4 0JQ, UK
| |
Collapse
|
80
|
Montesinos E, Bardají E. Synthetic antimicrobial peptides as agricultural pesticides for plant-disease control. Chem Biodivers 2008; 5:1225-37. [PMID: 18649311 DOI: 10.1002/cbdv.200890111] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There is a need of antimicrobial compounds in agriculture for plant-disease control, with low toxicity and reduced negative environmental impact. Antimicrobial peptides are produced by living organisms and offer strong possibilities in agriculture because new compounds can be developed based on natural structures with improved properties of activity, specificity, biodegradability, and toxicity. Design of new molecules has been achieved using combinatorial-chemistry procedures coupled to high-throughput screening systems and data processing with design-of-experiments (DOE) methodology to obtain QSAR equation models and optimized compounds. Upon selection of best candidates with low cytotoxicity and moderate stability to protease digestion, anti-infective activity has been evaluated in plant-pathogen model systems. Suitable compounds have been submitted to acute toxicity testing in higher organisms and exhibited a low toxicity profile in a mouse model. Large-scale production can be achieved by solution organic or chemoenzymatic procedures in the case of very small peptides, but, in many cases, production can be performed by biotechnological methods using genetically modified microorganisms (fermentation) or transgenic crops (plant biofactories).
Collapse
Affiliation(s)
- Emilio Montesinos
- Institute of Food and Agricultural Technology-CIDSAV-XaRTA, University of Girona, Campus Montilivi, E-18071 Girona.
| | | |
Collapse
|
81
|
Cirioni O, Silvestri C, Ghiselli R, Orlando F, Riva A, Mocchegiani F, Chiodi L, Castelletti S, Gabrielli E, Saba V, Scalise G, Giacometti A. Protective effects of the combination of alpha-helical antimicrobial peptides and rifampicin in three rat models of Pseudomonas aeruginosa infection. J Antimicrob Chemother 2008; 62:1332-8. [PMID: 18799470 DOI: 10.1093/jac/dkn393] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
INTRODUCTION An experimental study has been performed to compare the in vitro activity and the in vivo efficacy of magainin II and cecropin A with or without rifampicin against control and multidrug-resistant Pseudomonas aeruginosa strains. METHODS In vitro experiments included MIC determinations and synergy studies. For in vivo studies, animals were given an intraperitoneal injection of P. aeruginosa lipopolysaccharide, P. aeruginosa ATCC 27853 and one clinical multiresistant P. aeruginosa strain. Groups of animals received intravenously isotonic sodium chloride solution, 10 mg/kg rifampicin, 1 mg/kg magainin II or 1 mg/kg cecropin A. Two groups of animals received a combined treatment with magainin II + rifampicin or cecropin A + rifampicin at the same dosages as the singly treated groups. In addition, a further group was treated with tazobactam/piperacillin (120 mg/kg). Lethality, bacterial growth in blood and peritoneum, and endotoxin and TNF-alpha concentrations in plasma were evaluated. RESULTS Combinations of alpha-helical antimicrobial peptides showed in vitro synergistic interaction. Magainin II and cecropin A exerted strong antimicrobial activity and achieved a significant reduction in plasma endotoxin and TNF-alpha concentrations when compared with control and rifampicin-treated groups. Rifampicin exhibited no anti-P. aeruginosa activity and good substantial impact on endotoxin and TNF-alpha plasma concentrations. Combined treatment groups had significant reductions in bacterial count, positive blood cultures and mortality rates when compared with singly treated and control groups. CONCLUSIONS Our results highlight the potential usefulness of these combinations that provide future therapeutic alternatives in P. aeruginosa infections.
Collapse
Affiliation(s)
- Oscar Cirioni
- Institute of Infectious Diseases and Public Health, Università Politecnica delle Marche, Ancona, Italy.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
82
|
Dixon DR, Karimi-Naser L, Darveau RP, Leung KP. The anti-endotoxic effects of the KSL-W decapeptide on Escherichia coli O55:B5 and various oral lipopolysaccharides. J Periodontal Res 2008; 43:422-30. [DOI: 10.1111/j.1600-0765.2007.01067.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
83
|
Jiang Z, Vasil AI, Hale JD, Hancock REW, Vasil ML, Hodges RS. Effects of net charge and the number of positively charged residues on the biological activity of amphipathic alpha-helical cationic antimicrobial peptides. Biopolymers 2008; 90:369-83. [PMID: 18098173 DOI: 10.1002/bip.20911] [Citation(s) in RCA: 337] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In our previous study, we utilized a 26-residue amphipathic alpha-helical antimicrobial peptide L-V13K (Chen et al., Antimicrob Agents Chemother 2007, 51, 1398-1406) as the framework to study the effects of peptide hydrophobicity on the mechanism of its antimicrobial action. In this study, we explored the effects of net charge and the number of positively charged residues on the hydrophilic/polar face of L-V13K on its biological activity (antimicrobial and hemolytic) and biophysical properties (hydrophobicity, amphipathicity, helicity, and peptide self-association). The net charge of V13K analogs at pH 7 varied between -5 and +10 and the number of positively charged residues varied from 1 to 10. The minimal inhibitory concentrations (MIC) against six strains of Pseudomonas aeruginosa as well as other gram-negative and gram-positive bacteria were determined along with the maximal peptide concentration that produces no hemolysis of human red blood cells (MHC). Our results show that the number of positively charged residues on the polar face and net charge are both important for both antimicrobial activity and hemolytic activity. The most dramatic observation is the sharp transition of hemolytic activity on increasing one positive charge on the polar face of V13K i.e., the change from +8 to +9 resulted in greater than 32-fold increase in hemolytic activity (250 microg/ml to <7.8 microg/ml, respectively).
Collapse
Affiliation(s)
- Ziqing Jiang
- Department of Biochemistry and Molecular Genetics, University of Colorado at Denver and Health Sciences Center, Aurora, CO 80045, USA
| | | | | | | | | | | |
Collapse
|
84
|
Hale JDF, Hancock REW. Alternative mechanisms of action of cationic antimicrobial peptides on bacteria. Expert Rev Anti Infect Ther 2008; 5:951-9. [PMID: 18039080 DOI: 10.1586/14787210.5.6.951] [Citation(s) in RCA: 373] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cationic antimicrobial peptides are a novel type of antibiotic offering much potential in the treatment of microbial-related diseases. They offer many advantages for commercial development, including a broad spectrum of action and modest size. However, despite the identification or synthetic production of thousands of such peptides, the mode of action remains elusive, except for a few examples. While the dogma for the mechanism of action of antimicrobial peptides against bacteria is believed to be through pore formation or membrane barrier disruption, some peptides clearly act differently and other intracellular target sites have been identified. This article presents an updated review of how cationic antimicrobial peptides are able to affect bacterial killing, with a focus on internal targets.
Collapse
Affiliation(s)
- John D F Hale
- University of British Columbia, Centre for Microbial Disease and Immunity Research, Department of Microbiology and Immunology, Lower Mall Research Station, Vancouver, BC V6T1Z4, Canada.
| | | |
Collapse
|
85
|
Leem JY, Park DS, Suh EY, Hur JH, Oh HW, Park HY. Isolation and functional analysis of a 24-residue linear alpha-helical antimicrobial peptide from Korean blackish cicada, Cryptotympana dubia (Homoptera). ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2007; 66:204-213. [PMID: 18000874 DOI: 10.1002/arch.20213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A new antimicrobial peptide, cryptonin, was isolated and characterized from the adult Korean blackish cicada, Cryptotympana dubia. It consists of 24 amino acid residues and has a molecular weight of 2,704 Da on mass spectroscopy. The predicted alpha-helical structure analysis and increased helix percent in 40% trifloroethanol of cryptonin suggests that it belongs to the typical linear alpha-helix forming peptide. Binding of the biotin-labeled cryptonin at the surface of E. coli cells and increased influx of propidium iodide in E. coli after cryptonin treatment indicates that it kills microbial cells by binding bacterial cell surfaces and disrupting the cell permeability. Cryptonin showed strong antibacterial (MIC 1.56-25 microg/ml) and antifungal (MIC 3.12-50 microg/ml) activities against tested bacteria and fungi including two antibiotic-resistant bacterial strains; methicilin-resistant S. aureus and vancomycin-resistant Enterococci (MIC 25 microg/ml, each).
Collapse
Affiliation(s)
- Jae Yoon Leem
- Insect Resources Research Center, KRIBB, Daejeon 305-806 [corrected] Korea
| | | | | | | | | | | |
Collapse
|
86
|
Energetics and partition of two cecropin-melittin hybrid peptides to model membranes of different composition. Biophys J 2007; 94:2128-41. [PMID: 18032555 DOI: 10.1529/biophysj.107.119032] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The energetics and partition of two hybrid peptides of cecropin A and melittin (CA(1-8)M(1-18) and CA(1-7)M(2-9)) with liposomes of different composition were studied by time-resolved fluorescence spectroscopy, isothermal titration calorimetry, and surface plasmon resonance. The study was carried out with large unilamellar vesicles of three different lipid compositions: 1,2-dimyristoil-sn-glycero-3-phosphocholine (DMPC), 1,2-dimyristoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DMPG), and a 3:1 binary mixture of DMPC/DMPG in a wide range of peptide/lipid ratios. The results are compatible with a model involving a strong electrostatic surface interaction between the peptides and the negatively charged liposomes, giving rise to aggregation and precipitation. A correlation is observed in the calorimetric experiments between the observed events and charge neutralization for negatively charged and mixed membranes. In the case of zwitterionic membranes, a very interesting case study was obtained with the smaller peptide, CA(1-7)M(2-9). The calorimetric results obtained for this peptide in a large range of peptide/lipid ratios can be interpreted on the basis of an initial and progressive surface coverage until a threshold concentration, where the orientation changes from parallel to perpendicular to the membrane, followed by pore formation and eventually membrane disruption. The importance of negatively charged lipids on the discrimination between bacterial and eukaryotic membranes is emphasized.
Collapse
|
87
|
Park SC, Kim MH, Hossain MA, Shin SY, Kim Y, Stella L, Wade JD, Park Y, Hahm KS. Amphipathic alpha-helical peptide, HP (2-20), and its analogues derived from Helicobacter pylori: pore formation mechanism in various lipid compositions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1778:229-41. [PMID: 17961502 DOI: 10.1016/j.bbamem.2007.09.020] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Revised: 09/22/2007] [Accepted: 09/25/2007] [Indexed: 01/25/2023]
Abstract
In a previous study, we determined that HP(2-20) (residues 2-20 of parental HP derived from the N-terminus of Helicobacter pylori Ribosomal Protein L1) and its analogue, HPA3, exhibit broad-spectrum antimicrobial activity. The primary objective of the present study was to gain insight into the relevant mechanisms of action using analogues of HP(2-20) together with model liposomes of various lipid compositions and electron microscopy. We determined that these analogues, HPA3 and HPA3NT3, exert potent antibacterial effects in low-salt buffer and antifungal activity against chitin-containing fungi, while having little or no hemolytic activity or cytotoxicity against mammalian cell lines. Our examination of the interaction of HP(2-20) and its analogues with liposomes showed that the peptides disturb both neutral and negatively-charged membranes, as demonstrated by the release of encapsulated fluorescent markers. The release of fluorescent markers induced by HP(2-20) and its analogues was inversely related to marker size. The pore created by HP(2-20) shows that the radius is approximately 1.8 nm, whereas HPA3, HPA3NT3, and melittin have apparent radii between 3.3 and 4.8 nm. Finally, as shown by electron microscopy, the liposomes and various microbial cells treated with HPA3 and HPA3NT3 showed oligomerization and blebbing similar to that seen with melittin, while HP(2-20) exhibited flabbiness. These results suggest that HP(2-20) may exert its antibiotic effects through a small pore (about 1.8 nm), whereas HPA3 and HPA3NT3 formed pores of a size consistent with those formed by melittin.
Collapse
Affiliation(s)
- Seong-Cheol Park
- Research Center for Proteineous Materials (RCPM), Chosun University, Gwangju, Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
88
|
Soltani S, Keymanesh K, Sardari S. In silicoanalysis of antifungal peptides. Expert Opin Drug Discov 2007; 2:837-47. [DOI: 10.1517/17460441.2.6.837] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
89
|
Abstract
AbstractAntibiotic resistance is increasing at a rate that far exceeds the pace of new development of drugs. Antimicrobial peptides, both synthetic and from natural sources, have raised interest as pathogens become resistant against conventional antibiotics. Indeed, one of the major strengths of this class of molecules is their ability to kill multidrug-resistant bacteria. Antimicrobial peptides are relatively small (6 to 100 aminoacids), amphipathic molecules of variable length, sequence and structure with activity against a wide range of microorganisms including bacteria, protozoa, yeast, fungi, viruses and even tumor cells. They usually act through relatively non-specific mechanisms resulting in membranolytic activity but they can also stimulate the innate immune response. Several peptides have already entered pre-clinical and clinical trials for the treatment of catheter site infections, cystic fibrosis, acne, wound healing and patients undergoing stem cell transplantation. We review the advantages of these molecules in clinical applications, their disadvantages including their low in vivo stability, high costs of production and the strategies for their discovery and optimization.
Collapse
|
90
|
Cirioni O, Silvestri C, Ghiselli R, Giacometti A, Orlando F, Mocchegiani F, Chiodi L, Vittoria AD, Saba V, Scalise G. Experimental study on the efficacy of combination of alpha-helical antimicrobial peptides and vancomycin against Staphylococcus aureus with intermediate resistance to glycopeptides. Peptides 2006; 27:2600-6. [PMID: 16797106 DOI: 10.1016/j.peptides.2006.05.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 05/11/2006] [Accepted: 05/11/2006] [Indexed: 11/17/2022]
Abstract
An experimental study has been performed to compare the in vitro activity and the in vivo efficacy of magainin II and cecropin A, two alpha-helical antimicrobial peptides, and vancomycin against Staphylococcus aureus with intermediate resistance to glycopeptides. In vitro experiments included MIC determination, time-kill and synergy studies. For in vivo studies, a mouse model of staphylococcal sepsis has been used. Main outcome measures were: lethality, quantitative blood cultures and detection of TNF-alpha and interleukin-6 (IL-6) plasma levels. Combinations of alpha-helical antimicrobial peptides showed in vitro synergistic interaction. Significant increase in efficacy was also observed in vivo: combined-treated groups had significant lower bacteremia when compared to single-treated groups. Magainin II combined with vancomycin exhibited the highest efficacy on all main outcome measurements. These results highlight the potential usefulness of these combinations and provide future therapeutic alternative in infections due to glycopeptides resistant staphylococci in the coming years.
Collapse
Affiliation(s)
- Oscar Cirioni
- Institute of Infectious Diseases and Public Health, Università Politecnica delle Marche, Clinica delle Malattie Infettive, c/o Ospedali Riuniti Ancona, Via Conca 71, 60200 Ancona AN, Italy.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
91
|
|
92
|
Rosenfeld Y, Barra D, Simmaco M, Shai Y, Mangoni ML. A synergism between temporins toward Gram-negative bacteria overcomes resistance imposed by the lipopolysaccharide protective layer. J Biol Chem 2006; 281:28565-74. [PMID: 16867990 DOI: 10.1074/jbc.m606031200] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Temporins are short and homologous antimicrobial peptides (AMPs) isolated from the frog skin of Rana genus. To date, very little is known about the biological significance of the presence of closely related AMPs in single living organisms. Here we addressed this question using temporins A, B, and L isolated from Rana temporaria. We found that temporins A and B are only weakly active toward Gram-negative bacteria. However, a marked synergism occurs when each is mixed with temporin L. To shed light on the underlying mechanisms involved in these activities, we used various experimental strategies to investigate: (i) the effect of the peptides' interaction on both the viability and membrane permeability of intact bacteria and spheroplasts; (ii) their interaction with lipopolysaccharides (LPS) and the effect of LPS on the oligomeric state of temporins, alone or combining one with another; (iii) their structure in solution and when bound to LPS, by using circular dichroism and ATR-FTIR spectroscopies. Our data reveal that temporin L synergizes with A and B by preventing their oligomerization in LPS. This should promote their translocation across the outer membrane into the cytoplasmic membrane. To the best of our knowledge, this is the first study that explains how a combination of native AMPs from the same species can overcome bacterial resistance imposed by the LPS leaflet.
Collapse
Affiliation(s)
- Yosef Rosenfeld
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | | | | | | | | |
Collapse
|
93
|
Dhople V, Krukemeyer A, Ramamoorthy A. The human beta-defensin-3, an antibacterial peptide with multiple biological functions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:1499-512. [PMID: 16978580 DOI: 10.1016/j.bbamem.2006.07.007] [Citation(s) in RCA: 208] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Revised: 06/13/2006] [Accepted: 07/13/2006] [Indexed: 12/21/2022]
Abstract
A group of interesting molecules called defensins exhibit multiple functions but have been primarily recognized to possess a broad spectrum of antimicrobial activities. Studies have reported two different types of defensins (alpha and beta) from human and animals, a cyclic theta defensin from rhesus, and several defensin-like peptides from plants. There is no amino acid sequence homology between these peptides, but they all contain three Cys-Cys disulfide linkages while the connectivities are different. Human beta-defensin-3 (HbetaD-3) is the most recently discovered member of the host-defense peptide family that has attracted much attention. This molecule is expressed either constitutively or induced upon a challenge, and a growing evidence indicates the involvement of such molecules in adaptive immunity as well. It has been shown to exhibit antibacterial activities towards Gram-negative and Gram-positive bacteria as well as an ability to act as a chemo-attractant. Analysis of NMR structural data suggested a symmetrical dimeric form of this peptide in solution, which consists of three beta strands and a short helix in the N-terminal region. While the disulfide linkages are known to provide the structural stability and stability against proteases, the biological relevance of this dimeric form was contradicted by another biological study. Since there is considerable current interest in developing HbetaD-3 for possible pharmaceutical applications, studies to further our understanding on the determinants of antibacterial activities and immunomodulatory function of HbetaD-3 are considered to be highly significant. The knowledge of its biosynthetic regulation will also help in understanding the role of HbetaD-3 in immunity. This article presents an overview of the expression and regulation of HbetaD-3 in humans, and the structure-function correlations among HbetaD-3 and its modified peptides are discussed emphasizing the functional importance. The future scope for studies on HbetaD-3 and design of short potent antimicrobial peptides, based on the native HbetaD-3 molecule, that do not interfere in the immunomodulatory function is also outlined.
Collapse
Affiliation(s)
- Vishnu Dhople
- Biophysics Research Division and Department of Chemistry, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | | | | |
Collapse
|
94
|
Saugar JM, Rodríguez-Hernández MJ, de la Torre BG, Pachón-Ibañez ME, Fernández-Reyes M, Andreu D, Pachón J, Rivas L. Activity of cecropin A-melittin hybrid peptides against colistin-resistant clinical strains of Acinetobacter baumannii: molecular basis for the differential mechanisms of action. Antimicrob Agents Chemother 2006; 50:1251-6. [PMID: 16569836 PMCID: PMC1426946 DOI: 10.1128/aac.50.4.1251-1256.2006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Acinetobacter baumannii has successfully developed resistance against all common antibiotics, including colistin (polymyxin E), the last universally active drug against this pathogen. The possible widespread distribution of colistin-resistant A. baumannii strains may create an alarming clinical situation. In a previous work, we reported differences in lethal mechanisms between polymyxin B (PXB) and the cecropin A-melittin (CA-M) hybrid peptide CA(1-8)M(1-18) (KWKLFKKIGIGAVLKVLTTGLPALIS-NH2) on colistin-susceptible strains (J. M. Saugar, T. Alarcón, S. López-Hernández, M. López-Brea, D. Andreu, and L. Rivas, Antimicrob. Agents Chemother. 46:875-878, 2002). We now demonstrate that CA(1-8)M(1-18) and three short analogues, namely CA(1-7)M(2-9) (KWKLFKKIGAVLKVL-NH2), its Nalpha-octanoyl derivative (Oct-KWKLFKKIGAVLKVL-NH2), and CA(1-7)M(5-9) (KWKLLKKIGAVLKVL-NH2) are active against two colistin-resistant clinical strains. In vitro, resistance to colistin sulfate was targeted to the outer membrane, as spheroplasts were equally lysed by a given peptide, regardless of their respective level of colistin resistance. The CA-M hybrids were more efficient than colistin in displacing lipopolysaccharide-bound dansyl-polymyxin B from colistin-resistant but not from colistin-susceptible strains. Similar improved performance of the CA-M hybrids in permeation of the inner membrane was observed, regardless of the resistance pattern of the strain. These results argue in favor of a possible use of CA-M peptides, and by extension other antimicrobial peptides with similar features, as alternative chemotherapy in colistin-resistant Acinetobacter infections.
Collapse
Affiliation(s)
- José María Saugar
- Centro de Investigaciones Biológicas (CSIC), Madrid, and Hospitales Universitarios Virgen del Rocío, Sevilla, Spain
| | | | | | | | | | | | | | | |
Collapse
|
95
|
Rosenfeld Y, Shai Y. Lipopolysaccharide (Endotoxin)-host defense antibacterial peptides interactions: role in bacterial resistance and prevention of sepsis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:1513-22. [PMID: 16854372 DOI: 10.1016/j.bbamem.2006.05.017] [Citation(s) in RCA: 225] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Revised: 05/05/2006] [Accepted: 05/12/2006] [Indexed: 10/24/2022]
Abstract
Lipopolysaccharide (LPS) is the major molecular component of the outer membrane of Gram-negative bacteria and serves as a physical barrier providing the bacteria protection from its surroundings. LPS is also recognized by the immune system as a marker for the detection of bacterial pathogen invasion, responsible for the development of inflammatory response, and in extreme cases to endotoxic shock. Because of these functions, the interaction of LPS with LPS binding molecules attracts great attention. One example of such molecules are antimicrobial peptides (AMPs). These are large repertoire of gene-encoded peptides produced by living organisms of all types, which serve as part of the innate immunity protecting them from pathogen invasion. AMPs are known to interact with LPS with high affinities. The biophysical properties of AMPs and their mode of interaction with LPS determine their biological function, susceptibility of bacteria to them, as well as the ability of LPS to activate the immune system. This review will discuss recent studies on the molecular mechanisms underlying these interactions, their effects on the resistance of the bacteria to AMPs, as well as their potential to neutralize LPS-induced endotoxic shock.
Collapse
Affiliation(s)
- Yosef Rosenfeld
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, 76100 Israel
| | | |
Collapse
|
96
|
Voss S, Welte S, Fotin-Mleczek M, Fischer R, Ulmer AJ, Jung G, Wiesmüller KH, Brock R. A CD14 domain with lipopolysaccharide-binding and -neutralizing activity. Chembiochem 2006; 7:275-86. [PMID: 16444757 DOI: 10.1002/cbic.200500257] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The interaction of lipopolysaccharide with CD14 plays a key role in signaling that activates an early defense against pathogens but also contributes to the development of sepsis and septic shock. Here we have mapped the entire 356-amino-acid protein with synthetic 20-amino-acid peptides and have identified a new lipopolysaccharide-binding domain with a strong LPS-neutralizing activity. Moreover, analysis of the structure-activity relationship of this peptide, which corresponds to amino acids 81-100 of human CD14, revealed that leucines 87, 91, and 94 are essential for these activities. The functional relevance of these residues was confirmed by cellular expression of mutant CD14 proteins that are no longer able to bind LPS. Furthermore, the peptide provided a basis for the generation of highly soluble analogues with stronger lipopolysaccharide-neutralizing activity.
Collapse
Affiliation(s)
- Söhnke Voss
- Institute for Cell Biology, Department of Molecular Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | | | | | | | | | | | | | | |
Collapse
|
97
|
Sato H, Feix JB. Peptide-membrane interactions and mechanisms of membrane destruction by amphipathic alpha-helical antimicrobial peptides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:1245-56. [PMID: 16697975 DOI: 10.1016/j.bbamem.2006.02.021] [Citation(s) in RCA: 378] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 02/15/2006] [Accepted: 02/16/2006] [Indexed: 10/24/2022]
Abstract
Antimicrobial peptides (AMPs) have received considerable interest as a source of new antibiotics with the potential for treatment of multiple-drug resistant infections. An important class of AMPs is composed of linear, cationic peptides that form amphipathic alpha-helices. Among the most potent of these are the cecropins and synthetic peptides that are hybrids of cecropin and the bee venom peptide, mellitin. Both cecropins and cecropin-mellitin hybrids exist in solution as unstructured monomers, folding into predominantly alpha-helical structures upon membrane binding with their long helical axis parallel to the bilayer surface. Studies using model membranes have shown that these peptides intercalate into the lipid bilayer just below the level of the phospholipid glycerol backbone in a location that requires expansion of the outer leaflet of the bilayer, and evidence from a variety of experimental approaches indicates that expansion and thinning of the bilayer are common characteristics during the early stages of antimicrobial peptide-membrane interactions. Subsequent disruption of the membrane permeability barrier may occur by a variety of mechanisms, leading ultimately to loss of cytoplasmic membrane integrity and cell death.
Collapse
Affiliation(s)
- Hiromi Sato
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | | |
Collapse
|
98
|
Rosenfeld Y, Papo N, Shai Y. Endotoxin (Lipopolysaccharide) Neutralization by Innate Immunity Host-Defense Peptides. J Biol Chem 2006; 281:1636-43. [PMID: 16293630 DOI: 10.1074/jbc.m504327200] [Citation(s) in RCA: 297] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Binding of lipopolysaccharide (LPS) to macrophages results in proinflammatory cytokine secretion. In extreme cases it leads to endotoxic shock. A few innate immunity antimicrobial peptides (AMPs) neutralize LPS activity. However, the underlying mechanism and properties of the peptides are not yet clear. Toward meeting this goal we investigated four AMPs and their fluorescently labeled analogs. These AMPs varied in composition, length, structure, and selectivity toward cells. The list included human LL-37 (37-mer), magainin (24-mer), a 15-mer amphipathic alpha-helix, and its D,L-amino acid structurally altered analog. The peptides were investigated for their ability to inhibit LPS-mediated cytokine release from RAW264.7 and bone marrow-derived primary macrophages, to bind LPS in solution, and when LPS is already bound to macrophages (fluorescence spectroscopy and confocal microscopy), to compete with LPS for its binding site on the CD14 receptor (flow cytometry) and affect LPS oligomerization. We conclude that a strong binding of a peptide to LPS aggregates accompanied by aggregate dissociation prevents LPS from binding to the carrier protein lipopolysaccharide-binding protein, or alternatively to its receptor, and hence inhibits cytokine secretion.
Collapse
Affiliation(s)
- Yosef Rosenfeld
- Department of Biological Chemistry, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | |
Collapse
|
99
|
Zhang L, Parente J, Harris SM, Woods DE, Hancock REW, Falla TJ. Antimicrobial peptide therapeutics for cystic fibrosis. Antimicrob Agents Chemother 2005; 49:2921-7. [PMID: 15980369 PMCID: PMC1168697 DOI: 10.1128/aac.49.7.2921-2927.2005] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Greater than 90% of lung infections in cystic fibrosis (CF) patients are caused by Pseudomonas aeruginosa, and the majority of these patients subsequently die from lung damage. Current therapies are either targeted at reducing obstruction, reducing inflammation, or reducing infection. To identify potential therapeutic agents for the CF lung, 150 antimicrobial peptides consisting of three distinct structural classes were screened against mucoid and multidrug-resistant clinical isolates of P. aeruginosa, Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Staphylococcus aureus. Five peptides that retained potent antimicrobial activities in physiological salt and divalent cation environment were further characterized in vivo using a rat chronic lung infection model. All animals were inoculated intratracheally with 10(4) P. aeruginosa mucoid PAO1 cells in agar beads. Three days following inoculation treatment was initiated. Animals were treated daily for 3 days with 100 microl of peptide solution (1 mg/ml) in 10 mM sodium citrate, which was deposited via either intratracheal instillation or aerosolization. Control animals received daily exposure to vehicle alone. At the end of the treatment the lungs of the animals were removed for quantitative culture. Four peptides, HBCM2, HBCM3, HBCPalpha-2, and HB71, demonstrated significant reduction in Pseudomonas bioburden in the lung of rats. Further in vivo studies provided direct evidence that anti-inflammatory activity was associated with three of these peptides. Therefore, small bioactive peptides have the potential to attack two of the components responsible for the progression of lung damage in the CF disease: infection and inflammation.
Collapse
Affiliation(s)
- Lijuan Zhang
- Helix Biomedix Inc., 22122 20th Ave. SE, Bothell, Washington 98021, USA.
| | | | | | | | | | | |
Collapse
|
100
|
Bowdish DME, Davidson DJ, Scott MG, Hancock REW. Immunomodulatory activities of small host defense peptides. Antimicrob Agents Chemother 2005; 49:1727-32. [PMID: 15855488 PMCID: PMC1087655 DOI: 10.1128/aac.49.5.1727-1732.2005] [Citation(s) in RCA: 245] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent studies have demonstrated that in addition to their antimicrobial activity, cationic host defense peptides, like the human cathelicidin LL-37, perform many activities relating to innate immunity, including the induction or modulation of chemokine and cytokine production, alteration of gene expression in host cells, and inhibition of proinflammatory responses of host cells to bacterial components such as lipopolysaccharide (LPS) in vitro and in vivo. To investigate if these properties are shared by smaller peptides, two cathelicidin peptides derived from bovine neutrophils, the 13-mer indolicidin and Bac2A, a linear 12-amino-acid derivative of bactenecin, were compared to the 37-amino-acid peptide LL-37. Indolicidin, like LL-37, inhibited LPS-induced tumor necrosis factor alpha (TNF-alpha) secretion, even when added up to an hour after the addition of Escherichia coli O111:B4 LPS to the human macrophage/monocyte-like THP-1 cell line. In contrast, Bac2A demonstrated no significant antiendotoxin activity. At low concentrations, indolicidin and LL-37 acted synergistically to suppress LPS-induced production of TNF-alpha. Indolicidin was analogous to LL-37 in its ability to induce the production of the chemokine interleukin-8 (IL-8) in a human bronchial cell line, 16HBE14o(-), but it was unable to induce production of IL-8 in THP-1 cells. In contrast, Bac2A was unable to induce IL-8 in either cell type. Conversely, Bac2A was chemotactic for THP-1 cells at concentrations between 10 and 100 mug/ml, while indolicidin and LL-37 were not chemotactic at these concentrations for THP-1 cells. This indicates that in addition to the potential for direct microbicidal activity, cationic host defense peptides may have diverse and complementary abilities to modulate the innate immune response.
Collapse
Affiliation(s)
- Dawn M E Bowdish
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, 2259 Lower Mall Road, Vancouver, British Columbia, Canada V6T 1Z4
| | | | | | | |
Collapse
|