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To J, Zhang X, Tam JP. Design of Potent and Salt-Insensitive Antimicrobial Branched Peptides. Polymers (Basel) 2023; 15:3594. [PMID: 37688220 PMCID: PMC10489980 DOI: 10.3390/polym15173594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/24/2023] [Accepted: 08/26/2023] [Indexed: 09/10/2023] Open
Abstract
Dendrimeric and branched peptides are polypeptides formed by diverse types of scaffolds to give them different forms. Previously, we reported a cascade-type, Lys-scaffolded antimicrobial peptide dendrimer D4R tethered with four RLYR tetrapeptides. Antimicrobial D4R is broad-spectrum, salt insensitive, and as potent as the natural-occurring tachyplesins, displaying minimum inhibitory concentrations (MIC) < 1 μM. However, the relationships between scaffolds and antimicrobial potency remain undefined. Here, we report the design of four novel types of peptide antimicrobials whose scaffolded backbones are lysine (Lys), iso-Lys, ornithine (Orn), or iso-Orn tethered with RLYR on their α- or sidechain-amines to give ε-, δ-, and their α-branched peptides. When assayed against ten microorganisms, the Lys-scaffolded α- and ε-branched peptides are broadly active, salt insensitive, and as potent as D4R and tachyplesins, whereas the corresponding Orn-scaffolded α- and δ-branched peptides are salt sensitive and much less potent, displaying MICs ranging from 1 to >500 μM. Structure-activity relationship studies suggested that Lys-scaffolds, but not Orn-scaffolds, can support a reverse turn to organize RLYR tetrapeptides as parallel β-strands to form an amphipathic structure with Leu-Tyr as a hydrophobic core. Together, these results provide a structural approach for designing potent and salt-insensitive dendrimeric or branched peptide antimicrobials.
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Affiliation(s)
| | | | - James P. Tam
- Synzymes and Natural Products Center (SYNC), School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
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2
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Ciulla MG, Gelain F. Structure-activity relationships of antibacterial peptides. Microb Biotechnol 2023; 16:757-777. [PMID: 36705032 PMCID: PMC10034643 DOI: 10.1111/1751-7915.14213] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 12/08/2022] [Accepted: 01/01/2023] [Indexed: 01/28/2023] Open
Abstract
Antimicrobial peptides play a crucial role in innate immunity, whose components are mainly peptide-based molecules with antibacterial properties. Indeed, the exploration of the immune system over the past 40 years has revealed a number of natural peptides playing a pivotal role in the defence mechanisms of vertebrates and invertebrates, including amphibians, insects, and mammalians. This review provides a discussion regarding the antibacterial mechanisms of peptide-based agents and their structure-activity relationships (SARs) with the aim of describing a topic that is not yet fully explored. Some growing evidence suggests that innate immunity should be strongly considered for the development of novel antibiotic peptide-based libraries. Also, due to the constantly rising concern of antibiotic resistance, the development of new antibiotic drugs is becoming a priority of global importance. Hence, the study and the understanding of defence phenomena occurring in the immune system may inspire the development of novel antibiotic compound libraries and set the stage to overcome drug-resistant pathogens. Here, we provide an overview of the importance of peptide-based antibacterial sources, focusing on accurately selected molecular structures, their SARs including recently introduced modifications, their latest biotechnology applications, and their potential against multi-drug resistant pathogens. Last, we provide cues to describe how antibacterial peptides show a better scope of action selectivity than several anti-infective agents, which are characterized by non-selective activities and non-targeted actions toward pathogens.
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Affiliation(s)
- Maria Gessica Ciulla
- Institute for Stem-Cell Biology, Regenerative Medicine and Innovative Therapies, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
- Center for Nanomedicine and Tissue Engineering (CNTE), ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Fabrizio Gelain
- Institute for Stem-Cell Biology, Regenerative Medicine and Innovative Therapies, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
- Center for Nanomedicine and Tissue Engineering (CNTE), ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
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3
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Brandner L, Müller TJJ. Multicomponent synthesis of chromophores – The one-pot approach to functional π-systems. Front Chem 2023; 11:1124209. [PMID: 37007054 PMCID: PMC10065161 DOI: 10.3389/fchem.2023.1124209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 01/26/2023] [Indexed: 03/19/2023] Open
Abstract
Multicomponent reactions, conducted in a domino, sequential or consecutive fashion, have not only considerably enhanced synthetic efficiency as one-pot methodology, but they have also become an enabling tool for interdisciplinary research. The highly diversity-oriented nature of the synthetic concept allows accessing huge structural and functional space. Already some decades ago this has been recognized for life sciences, in particular, lead finding and exploration in pharma and agricultural chemistry. The quest for novel functional materials has also opened the field for diversity-oriented syntheses of functional π-systems, i.e. dyes for photonic and electronic applications based on their electronic properties. This review summarizes recent developments in MCR syntheses of functional chromophores highlighting syntheses following either the framework forming scaffold approach by establishing connectivity between chromophores or the chromogenic chromophore approach by de novo formation of chromophore of interest. Both approaches warrant rapid access to molecular functional π-systems, i.e. chromophores, fluorophores, and electrophores for various applications.
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4
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Lu S, Lin J, Jin J, Zhang L, Guan Y, Chen H, Wu Y, Zhang W, Luan X. Tachyplesin I and its derivatives: A pharmaco-chemical perspective on their antimicrobial and antitumor potential. Expert Opin Drug Discov 2022; 17:1407-1423. [PMID: 36503335 DOI: 10.1080/17460441.2023.2157402] [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: 12/14/2022]
Abstract
INTRODUCTION Increasing evidence suggests that intratumor microbiota are an intrinsic component in the tumor microenvironment across multiple cancer types, and that there is a close relationship between microbiota and tumor progression. Therefore, how to address the interaction between bacteria and malignances has become a growing concern. Tachyplesin I (TPI), a peptide with dual antimicrobial and antitumor effects, holds great promise as a therapeutic alternative for the aforementioned diseases, with the advantage of broad-spectrum activities, quick killing efficacy, and a low tendency to induce resistance. AREAS COVERED This review comprehensively summarizes the pharmacological mechanisms of TPI with an emphasis on its antimicrobial and antitumor potential. Furthermore, it presents advances in TPI derivatives and gives a perspective on their future development. The article is based on literature searches using PubMed and SciFinder to retrieve the most up-to-date information of TPI. EXPERT OPINION Bacterial infections and cancer both pose a serious threat to health due to their symbiotic interactions and drug resistance. TPI is anticipated to be a novel agent to control pathogenic bacteria and various tumors through multiple mechanisms of action. Indeed, the continuous advancements in chemical modification and innovative applications of TPI give hope for future improvements in therapeutic efficacy.
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Affiliation(s)
- Shengxin Lu
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
| | - Jiayi Lin
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
| | - Jinmei Jin
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
| | - Lijun Zhang
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
| | - Yingyun Guan
- Department of Pharmacy, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Municipality, Shanghai, China
| | - Hongzhuan Chen
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
| | - Ye Wu
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
| | - Weidong Zhang
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China.,School of Pharmacy, Naval Medical University, Municipality, Shanghai, China
| | - Xin Luan
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Municipality, Shanghai, China
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5
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Mechanism of Action and Therapeutic Potential of the β-Hairpin Antimicrobial Peptide Capitellacin from the Marine Polychaeta Capitella teleta. Mar Drugs 2022; 20:md20030167. [PMID: 35323465 PMCID: PMC8953592 DOI: 10.3390/md20030167] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 02/06/2023] Open
Abstract
Among the most potent and proteolytically resistant antimicrobial peptides (AMPs) of animal origin are molecules forming a β-hairpin structure stabilized by disulfide bonds. In this study, we investigated the mechanism of action and therapeutic potential of the β-hairpin AMP from the marine polychaeta Capitella teleta, named capitellacin. The peptide exhibits a low cytotoxicity toward mammalian cells and a pronounced activity against a wide range of bacterial pathogens including multi-resistant bacteria, but the mechanism of its antibacterial action is still obscure. In view of this, we obtained analogs of capitellacin and tachyplesin-inspired chimeric variants to identify amino acid residues important for biological activities. A low hydrophobicity of the β-turn region in capitellacin determines its modest membranotropic activity and slow membrane permeabilization. Electrochemical measurements in planar lipid bilayers mimicking the E. coli membrane were consistent with the detergent-like mechanism of action rather than with binding to a specific molecular target in the cell. The peptide did not induce bacterial resistance after a 21-day selection experiment, which also pointed at a membranotropic mechanism of action. We also found that capitellacin can both prevent E. coli biofilm formation and destroy preformed mature biofilms. The marked antibacterial and antibiofilm activity of capitellacin along with its moderate adverse effects on mammalian cells make this peptide a promising scaffold for the development of drugs for the treatment of chronic E. coli infections, in particular those caused by the formation of biofilms.
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Liu Y, Sameen DE, Ahmed S, Dai J, Qin W. Antimicrobial peptides and their application in food packaging. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.04.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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7
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Kumar V, Chugh A. Peptide-mediated leishmaniasis management strategy: Tachyplesin emerges as an effective anti-leishmanial peptide against Leishmania donovani. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183629. [PMID: 33933430 DOI: 10.1016/j.bbamem.2021.183629] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 04/18/2021] [Accepted: 04/20/2021] [Indexed: 01/23/2023]
Abstract
Visceral leishmaniasis is one of the neglected tropical diseases caused by an intracellular parasite, Leishmania donovani. Drug resistance, adverse side effects and long treatment regimes are important limitations in achieving the effective elimination of visceral leishmaniasis. In the absence of any vaccine, chemotherapy remains a viable treatment for leishmaniasis. For effective killing of leishmania parasite, the drug molecule needs to cross the cell membrane. In the present study, marine membrane-active peptide Tachyplesin has been used against Leishmania donovani. Further, the mechanism of action and importance of cysteine amino acids of Tachyplesin in anti-leishmanial activity has been assessed. The cargo-carrying ability of Tachyplesin in L. donovani has been established. Thus, dual-use of Tachyplesin as an anti-leishmanial peptide as well as a cargo delivery vehicle makes the marine peptide an attractive therapeutic target against visceral leishmaniasis.
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Affiliation(s)
- Vivek Kumar
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Archana Chugh
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi 110016, India.
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8
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Hou H, Wang J, Wang J, Tang W, Shaikh AS, Li Y, Fu J, Lu L, Wang F, Sun F, Tan H. A Review of Bioactive Peptides: Chemical Modification, Structural Characterization and Therapeutic Applications. J Biomed Nanotechnol 2021; 16:1687-1718. [PMID: 33485398 DOI: 10.1166/jbn.2020.3001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In recent years, the development and applications of protein drugs have attracted extensive attention from researchers. However, the shortcomings of protein drugs also limit their further development. Therefore, bioactive peptides isolated or simulated from protein polymers have broad application prospects in food, medicine, biotechnology, and other industries. Such peptides have a molecular weight distribution between 180 and 1000 Da. As a small molecule substance, bioactive peptide is usually degraded by various enzymes in the organism and have a short half-life. At the same time, such substances have poor stability and are difficult to produce and store. Therefore, these active peptides may be modified through phosphorylation, glycosylation, and acylation. Compared with other protein drugs, the modified active peptides are more easily absorbed by the body, have longer half-life, stronger targeting, and fewer side effects in addition to higher bioavailability. In the light of their functions, bioactive peptide can be divided into antimicrobial, anti-tumour, anti-angiogenic, antioxidant, anti-fatigue, and anti-hypertensive peptides. This article mainly focuses on the introduction of several promising biologically active peptides functioning as antimicrobial, anti-tumour, antiangiogenic, and antioxidant peptides from the three aspects modification, structural characteristics and mechanism of action.
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9
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Panteleev PV, Tsarev AV, Safronova VN, Reznikova OV, Bolosov IA, Sychev SV, Shenkarev ZO, Ovchinnikova TV. Structure Elucidation and Functional Studies of a Novel β-hairpin Antimicrobial Peptide from the Marine Polychaeta Capitella teleta. Mar Drugs 2020; 18:md18120620. [PMID: 33291782 PMCID: PMC7761999 DOI: 10.3390/md18120620] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/27/2020] [Accepted: 12/02/2020] [Indexed: 12/21/2022] Open
Abstract
Endogenous antimicrobial peptides (AMPs) are evolutionary ancient molecular factors of innate immunity that play a key role in host defense. Among the most active and stable under physiological conditions AMPs are the peptides of animal origin that adopt a β-hairpin conformation stabilized by disulfide bridges. In this study, a novel BRICHOS-domain related AMP from the marine polychaeta Capitella teleta, named capitellacin, was produced as the recombinant analogue and investigated. The mature capitellacin exhibits high homology with the known β-hairpin AMP family—tachyplesins and polyphemusins from the horseshoe crabs. The β-hairpin structure of the recombinant capitellacin was proved by CD and NMR spectroscopy. In aqueous solution the peptide exists as monomeric right-handed twisted β-hairpin and its structure does not reveal significant amphipathicity. Moreover, the peptide retains this conformation in membrane environment and incorporates into lipid bilayer. Capitellacin exhibits a strong antimicrobial activity in vitro against a wide panel of bacteria including extensively drug-resistant strains. In contrast to other known β-hairpin AMPs, this peptide acts apparently via non-lytic mechanism at concentrations inhibiting bacterial growth. The molecular mechanism of the peptide antimicrobial action does not seem to be related to the inhibition of bacterial translation therefore other molecular targets may be assumed. The reduced cytotoxicity against human cells and high antibacterial cell selectivity as compared to tachyplesin-1 make it an attractive candidate compound for an anti-infective drug design.
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Affiliation(s)
- Pavel V. Panteleev
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Andrey V. Tsarev
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Victoria N. Safronova
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Olesia V. Reznikova
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Ilia A. Bolosov
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Sergei V. Sychev
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Zakhar O. Shenkarev
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
| | - Tatiana V. Ovchinnikova
- M.M. Shemyakin & Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, the Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow, Russia; (P.V.P.); (A.V.T.); (V.N.S.); (O.V.R.); (I.A.B.); (S.V.S.); (Z.O.S.)
- Department of Biotechnology, I.M. Sechenov First Moscow State Medical University, Trubetskaya str., 8–2, 119991 Moscow, Russia
- Correspondence: ; Tel.: +7-495-336-44-44
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10
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Aziz M, Garduno R, Mirani ZA, Baqai R, Sheikh AS, Nazir H, Raza Y, Ayaz M, Kazmi SU. Determination of antimicrobial effect of protamine by transmission electron microscopy and SDS PAGE on Pseudomonas aeruginosa isolates from diabetic foot infection. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2020; 22:827-832. [PMID: 32373306 PMCID: PMC7196347 DOI: 10.22038/ijbms.2019.32414.7989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Objective(s): Diabetic foot infection is one of the major complications of diabetes leading to lower limb amputations. Isolation and identification of bacteria causing diabetic foot infection, determination of antibiotic resistance, antimicrobial potential of protamine by electron microscopy and SDS-PAGE analysis, arethe aims of this study. Materials and Methods: 285 pus samples from diabetic foot infection patients were collected from different hospitals of Karachi and Capital Health Hospital, Halifax, Canada. Clinical history of each patient was recorded. Bacterial isolates were cultured on appropriate media; identification was done by morphology, cultural and biochemical tests. Effect of protamine against multi drug resistant strains of Pseudomona aeruginosa was checked by minimum inhibitory concentration in 96 well micro-titer plates. The isolates were grown in bactericidal concentration of protamine on plates to isolate mutants. Effect of protamine on protein expression was checked by SDS- PAGE and ultra-structural morphological changes by transmission electron microscopy. Results: Results indicated prevalence of foot infection as 92% in diabetic patients. Major bacterial isolates were Staphylococcus aureus 65 (23%), P. aeruginosa 80 (28.1%), Klebsiella spp. 37 (13%), Proteus mirabilis 79 (27.7%), and Escherichia coli 24 (12%). These isolates were highly resistant to different antibiotics. MIC value of protamine was 500 µg/ml against P. aeruginosa. SDS-PAGE analysis revealed that protamine can suppress expression of various virulence proteins and electron micrographs indicated condensation of cytoplasm and accumulation of protamine in cytoplasm without damaging the cell membrane. Conclusion: P. aeruginosa and S. aureus were the major isolates expressing multi-drug resistance and protamine sulfate represented good antimicrobial potential.
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Affiliation(s)
- Mubashar Aziz
- Department of Pathobiology, Bahauddin Zakariya University, Multan, Pakistan.,Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Rafael Garduno
- Department of Microbiology, Dalhousie University, Halifax, Canada
| | | | - Rakhshanda Baqai
- Department of Microbiology, University of Karachi, Karachi, Pakistan.,Departmet of Clinical Microbiology & Immunology, Dadabhoy Institute of Higher Education, Karachi, Pakistan
| | - Ahsan Sattar Sheikh
- Institute of Food Science and Nutrition, Bahauddin Zakariya University, Multan, Pakistan
| | | | - Yasir Raza
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Mazhar Ayaz
- Department of Pathobiology, Bahauddin Zakariya University, Multan, Pakistan
| | - Shahana Urooj Kazmi
- Department of Microbiology, University of Karachi, Karachi, Pakistan.,Departmet of Clinical Microbiology & Immunology, Dadabhoy Institute of Higher Education, Karachi, Pakistan
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11
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Yu R, Wang J, So LY, Harvey PJ, Shi J, Liang J, Dou Q, Li X, Yan X, Huang YH, Xu Q, Kaas Q, Chow HY, Wong KY, Craik DJ, Zhang XH, Jiang T, Wang Y. Enhanced Activity against Multidrug-Resistant Bacteria through Coapplication of an Analogue of Tachyplesin I and an Inhibitor of the QseC/B Signaling Pathway. J Med Chem 2020; 63:3475-3484. [PMID: 32003561 DOI: 10.1021/acs.jmedchem.9b01563] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tachyplesin I (TPI) is a cationic β-hairpin antimicrobial peptide with broad-spectrum, potent antimicrobial activity. In this study, the all d-amino acid analogue of TPI (TPAD) was synthesized, and its structure and activity were determined. TPAD has comparable antibacterial activity to TPI on 14 bacterial strains, including four drug-resistant bacteria. Importantly, TPAD has significantly improved stability against enzymatic degradation and decreased hemolytic activity compared to TPI, indicating that it has better therapeutic potential. The induction of bacterial resistance using low concentrations of TPAD resulted in the activation of the QseC/B two-component system. Deletion of this system resulted in at least five-fold improvement of TPAD activity, and the combined use of TPAD with LED209, a QseC/B inhibitor, significantly enhanced the bactericidal effect against three classes of multidrug-resistant bacteria.
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Affiliation(s)
- Rilei Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Jiayi Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Lok-Yan So
- Department of Applied Biology and Chemical Technology and the State Key Laboratory of Chemical Biology and Drug Discovery, The Hong Kong Polytechnic University, Kowloon 999077, Hong Kong
| | - Peta J Harvey
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Juan Shi
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Jiazhen Liang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Qin Dou
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Xiao Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Xiayi Yan
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Yen-Hua Huang
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Qingliang Xu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Quentin Kaas
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Ho-Yin Chow
- Department of Applied Biology and Chemical Technology and the State Key Laboratory of Chemical Biology and Drug Discovery, The Hong Kong Polytechnic University, Kowloon 999077, Hong Kong
| | - Kwok-Yin Wong
- Department of Applied Biology and Chemical Technology and the State Key Laboratory of Chemical Biology and Drug Discovery, The Hong Kong Polytechnic University, Kowloon 999077, Hong Kong
| | - David J Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Xiao-Hua Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Tao Jiang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
| | - Yan Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
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12
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Dong N, Wang C, Li X, Guo Y, Li X. Simplified Head-to-Tail Cyclic Polypeptides as Biomaterial-Associated Antimicrobials with Endotoxin Neutralizing and Anti-Inflammatory Capabilities. Int J Mol Sci 2019; 20:ijms20235904. [PMID: 31775224 PMCID: PMC6928678 DOI: 10.3390/ijms20235904] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/15/2019] [Accepted: 11/20/2019] [Indexed: 12/21/2022] Open
Abstract
The therapeutic application of antimicrobial peptides (AMPs), a potential type of peptide-based biomaterial, is impeded by their poor antimicrobial activity and potential cytotoxicity as a lack of understanding of their structure–activity relationships. In order to comprehensively enhance the antibacterial and clinical application potency of AMPs, a rational approach was applied to design amphiphilic peptides, including head-to-tail cyclic, linear and D-proline antimicrobial peptides using the template (IR)nP(IR)nP (n = 1, 2 and 3). Results showed that these amphiphilic peptides demonstrated antimicrobial activity in a size-dependent manner and that cyclic peptide OIR3, which contained three repeating units (IR)3, had greater antimicrobial potency and cell selectivity than liner peptide IR3, DIR3 with D-Pro and gramicidin S (GS). Surface plasmon resonance and endotoxin neutralization assays indicated that OIR3 had significant endotoxin neutralization capabilities, which suggested that the effects of OIR3 were mediated by binding to lipopolysaccharides (LPS). Using fluorescence spectrometry and electron microscopy, we found that OIR3 strongly promoted membrane disruption and thereby induced cell lysis. In addition, an LPS-induced inflammation assay showed that OIR3 inhibited the pro-inflammatory factor TNF-α in RAW264.7 cells. OIR3 was able to reduce oxazolone-induced skin inflammation in allergic dermatitis mouse model via the inhibition of TNF-α, IL-1β and IL-6 mRNA expression. Collectively, the engineered head-to-tail cyclic peptide OIR3 was considerable potential candidate for use as a clinical therapeutic for the treatment of bacterial infections and skin inflammation.
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Affiliation(s)
- Na Dong
- The Laboratory of Molecular Nutrition and Immunity, Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (N.D.); (C.W.); (X.L.)
| | - Chensi Wang
- The Laboratory of Molecular Nutrition and Immunity, Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (N.D.); (C.W.); (X.L.)
| | - Xinran Li
- The Laboratory of Molecular Nutrition and Immunity, Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (N.D.); (C.W.); (X.L.)
| | - Yuming Guo
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
- Correspondence: ; Tel.: +(86-010)-6273-3900
| | - Xiaoli Li
- Heilongjiang Key Laboratory of Molecular Design and Preparation of Flame Retarded Materials, College of Science, Northeast Forestry University, Harbin 150040, China;
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13
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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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14
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Borges A, Gillespie D, Nag A. Biological applications of amide and amino acid containing synthetic macrocycles. Supramol Chem 2019. [DOI: 10.1080/10610278.2019.1650178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Ariane Borges
- Department of Chemistry, Clark University, Worcester, MA, USA
| | - Dylan Gillespie
- Department of Chemistry, Clark University, Worcester, MA, USA
| | - Arundhati Nag
- Department of Chemistry, Clark University, Worcester, MA, USA
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15
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Kuppusamy R, Willcox M, Black DS, Kumar N. Short Cationic Peptidomimetic Antimicrobials. Antibiotics (Basel) 2019; 8:antibiotics8020044. [PMID: 31003540 PMCID: PMC6628222 DOI: 10.3390/antibiotics8020044] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 04/15/2019] [Accepted: 04/15/2019] [Indexed: 12/28/2022] Open
Abstract
The rapid growth of antimicrobial resistance against several frontline antibiotics has encouraged scientists worldwide to develop new alternatives with unique mechanisms of action. Antimicrobial peptides (AMPs) have attracted considerable interest due to their rapid killing and broad-spectrum activity. Peptidomimetics overcome some of the obstacles of AMPs such as high cost of synthesis, short half-life in vivo due to their susceptibility to proteolytic degradation, and issues with toxicity. This review will examine the development of short cationic peptidomimetics as antimicrobials.
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Affiliation(s)
- Rajesh Kuppusamy
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Mark Willcox
- School of Optometry and Vision Science, University of New South Wales, Sydney, NSW 2052, Australia.
| | - David StC Black
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Naresh Kumar
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.
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16
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Barbosa SC, Nobre TM, Volpati D, Cilli EM, Correa DS, Oliveira ON. The cyclic peptide labaditin does not alter the outer membrane integrity of Salmonella enterica serovar Typhimurium. Sci Rep 2019; 9:1993. [PMID: 30760803 PMCID: PMC6374527 DOI: 10.1038/s41598-019-38551-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 12/27/2018] [Indexed: 12/21/2022] Open
Abstract
Antimicrobial peptides are a promising class of new antibiotics with the ability to kill bacteria by disrupting their cell membrane, which is especially difficult for Gram-negative bacteria whose cell wall contains an outer layer of lipopolysaccharides (LPS). Here we show that the cyclic decapeptide Labaditin (Lo), with proven activity against the Gram-positive Staphylococcus aureus and Streptococcus mutans, is not able to kill the Gram-negative Salmonella enterica serovar Typhimurium (S.e.s. Typhimurium). We found that Lo induced significant changes in the surface pressure isotherms of Langmuir monolayers representing the Salmonella enterica serovar Typhimurium inner membrane (S.e.s. Typhimurium IM), and caused leakage in large unilamellar vesicles made with this IM lipid composition. On the basis of these results one should expect bactericidal activity against S.e.s. Typhimurium. However, Lo could not interact with a monolayer of LPS, causing no significant changes in either the surface pressure isotherms or in the polarization-modulated infrared reflection absorption spectra (PM-IRRAS). Therefore, the failure of Lo to kill S.e.s. Typhimurium is associated with the lack of interaction with LPS from the outer bacteria membrane. Our approach with distinct monolayer compositions and combined techniques to investigate molecular-level interactions is useful for drug design to fight antibiotic-resistant bacteria.
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Affiliation(s)
- Simone C Barbosa
- São Carlos Institute of Physics, University of São Paulo, CP 369, 13560-970, São Carlos-SP, Brazil
| | - Thatyane M Nobre
- São Carlos Institute of Physics, University of São Paulo, CP 369, 13560-970, São Carlos-SP, Brazil
| | | | - Eduardo M Cilli
- Universidade Estadual Paulista (UNESP), Institute of Chemistry, 14800-060, Araraquara-SP, Brazil
| | - Daniel S Correa
- Nanotechnology National Laboratory for Agriculture (LNNA), Embrapa Instrumentação, 13560-970, São Carlos, SP, Brazil
| | - Osvaldo N Oliveira
- São Carlos Institute of Physics, University of São Paulo, CP 369, 13560-970, São Carlos-SP, Brazil.
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17
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Cameron AJ, Varnava KG, Edwards PJB, Harjes E, Sarojini V. Acyclic peptides incorporating the d-Phe-2-Abz turn motif: Investigations on antimicrobial activity and propensity to adopt β-hairpin conformations. J Pept Sci 2018; 24:e3094. [PMID: 29900628 DOI: 10.1002/psc.3094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 05/08/2018] [Accepted: 05/16/2018] [Indexed: 02/01/2023]
Abstract
Three linear peptides incorporating d-Phe-2-Abz as the turn motif are reported. Peptide 1, a hydrophobic β-hairpin, served as a proof of principle for the design strategy with both NMR and CD spectra strongly suggesting a β-hairpin conformation. Peptides 2 and 3, designed as amphipathic antimicrobials, exhibited broad spectrum antimicrobial activity, with potency in the nanomolar range against Staphylococcus aureus. Both compounds possess a high degree of selectivity, proving non-haemolytic at concentrations 500 to 800 times higher than their respective minimal inhibitory concentrations (MICs) against S. aureus. Peptide 2 induced cell membrane and cell wall disintegration in both S. aureus and Pseudomonas aeruginosa as observed by transmission electron microscopy. Peptide 2 also demonstrated moderate antifungal activity against Candida albicans with an MIC of 50 μM. Synergism was observed with sub-MIC levels of amphotericin B (AmB), leading to nanomolar MICs against C. albicans for peptide 2. Based on circular dichroism spectra, both peptides 2 and 3 appear to exist as a mixture of conformers with the β-hairpin as a minor conformer in aqueous solution, and a slight increase in hairpin population in 50% trifluoroethanol, which was more pronounced for peptide 3. NMR spectra of peptide 2 in a 1:1 CD3 CN/H2 O mixture and 30 mM deuterated sodium dodecyl sulfate showed evidence of an extended backbone conformation of the β-strand residues. However, inter-strand rotating frame Overhauser effects (ROE) could not be detected and a loosely defined divergent hairpin structure resulted from ROE structure calculation in CD3 CN/H2 O. The loosely defined hairpin conformation is most likely a result of the electrostatic repulsions between cationic strand residues which also probably contribute towards maintaining low haemolytic activity.
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Affiliation(s)
- Alan J Cameron
- School of Chemical Sciences, The University of Auckland, Auckland, 1142, New Zealand
| | - Kyriakos G Varnava
- School of Chemical Sciences, The University of Auckland, Auckland, 1142, New Zealand
| | - Patrick J B Edwards
- Institute of Fundamental Sciences, Massey University, Palmerston North, 4442, New Zealand
| | - Elena Harjes
- Institute of Fundamental Sciences, Massey University, Palmerston North, 4442, New Zealand
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18
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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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19
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Kozic M, Fox SJ, Thomas JM, Verma CS, Rigden DJ. Large scale ab initio modeling of structurally uncharacterized antimicrobial peptides reveals known and novel folds. Proteins 2018; 86:548-565. [DOI: 10.1002/prot.25473] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/16/2018] [Accepted: 01/29/2018] [Indexed: 12/20/2022]
Affiliation(s)
- Mara Kozic
- Institute of Integrative Biology, University of Liverpool; Liverpool L69 7ZB U.K
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute; Singapore
| | - Stephen J. Fox
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute; Singapore
| | - Jens M. Thomas
- Institute of Integrative Biology, University of Liverpool; Liverpool L69 7ZB U.K
| | - Chandra S. Verma
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute; Singapore
- Department of Biological Sciences; National University of Singapore; Singapore
- School of Biological Sciences; Nanyang Technological University; Singapore
| | - Daniel J. Rigden
- Institute of Integrative Biology, University of Liverpool; Liverpool L69 7ZB U.K
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20
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Manzo G, Serra I, Pira A, Pintus M, Ceccarelli M, Casu M, Rinaldi AC, Scorciapino MA. The singular behavior of a β-type semi-synthetic two branched polypeptide: three-dimensional structure and mode of action. Phys Chem Chem Phys 2018; 18:30998-31011. [PMID: 27805179 DOI: 10.1039/c6cp05464a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dendrimeric peptides make a versatile group of bioactive peptidomimetics and a potential new class of antimicrobial agents to tackle the pressing threat of multi-drug resistant pathogens. These are branched supramolecular assemblies where multiple copies of the bioactive unit are linked to a central core. Beyond their antimicrobial activity, dendrimeric peptides could also be designed to functionalize the surface of nanoparticles or materials for other medical uses. Despite these properties, however, little is known about the structure-function relationship of such compounds, which is key to unveil the fundamental physico-chemical parameters and design analogues with desired attributes. To close this gap, we focused on a semi-synthetic, two-branched peptide, SB056, endowed with remarkable activity against both Gram-positive and Gram-negative bacteria and limited cytotoxicity. SB056 can be considered the smallest prototypical dendrimeric peptide, with the core restricted to a single lysine residue and only two copies of the same highly cationic 10-mer polypeptide; an octanamide tail is present at the C-terminus. Combining NMR and Molecular Dynamics simulations, we have determined the 3D structure of two analogues. Fluorescence spectroscopy was applied to investigate the water-bilayer partition in the presence of vesicles of variable charge. Vesicle leakage assays were also performed and the experimental data were analyzed by applying an iterative Monte Carlo scheme to estimate the minimum number of bound peptides needed to achieve the release. We unveiled a singular beta hairpin-type structure determined by the peptide chains only, with the octanamide tail available for further functionalization to add new potential properties without affecting the structure.
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Affiliation(s)
- Giorgia Manzo
- Department of Biomedical Sciences - Biochemistry Unit, University of Cagliari, Monserrato, CA, Italy.
| | - Ilaria Serra
- Department of Chemical and Geological Sciences, University of Cagliari, Monserrato, CA, Italy
| | - Alessandro Pira
- Department of Chemical and Geological Sciences, University of Cagliari, Monserrato, CA, Italy
| | - Manuela Pintus
- Department of Biomedical Sciences - Biochemistry Unit, University of Cagliari, Monserrato, CA, Italy.
| | - Matteo Ceccarelli
- Department of Physics, University of Cagliari, Monserrato, CA, Italy
| | - Mariano Casu
- Department of Physics, University of Cagliari, Monserrato, CA, Italy
| | - Andrea C Rinaldi
- Department of Biomedical Sciences - Biochemistry Unit, University of Cagliari, Monserrato, CA, Italy.
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21
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Optimisation of the antifungal potency of the amidated peptide H-Orn-Orn-Trp-Trp-NH2 against food contaminants. Int J Food Microbiol 2018; 265:40-48. [DOI: 10.1016/j.ijfoodmicro.2017.10.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 09/03/2017] [Accepted: 10/20/2017] [Indexed: 12/19/2022]
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22
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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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23
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Balandin SV, Ovchinnikova TV. Antimicrobial peptides of invertebrates. Part 2. biological functions and mechanisms of action. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2016. [DOI: 10.1134/s106816201604004x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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24
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Enhanced resistance to Sclerotinia sclerotiorum in Brassica napus by co-expression of defensin and chimeric chitinase genes. J Appl Genet 2016; 57:417-425. [PMID: 26862081 DOI: 10.1007/s13353-016-0340-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 01/19/2016] [Accepted: 01/25/2016] [Indexed: 01/19/2023]
Abstract
Sclerotinia stem rot caused by Sclerotinia sclerotiorum is one of the major fungal diseases of Brassica napus L. To develop resistance against this fungal disease, the defensin gene from Raphanus sativus and chimeric chit42 from Trichoderma atroviride with a C-terminal fused chitin-binding domain from Serratia marcescens were co-expressed in canola via Agrobacterium-mediated transformation. Twenty transformants were confirmed to carry the two transgenes as detected by polymerase chain reaction (PCR), with 4.8 % transformation efficiency. The chitinase activity of PCR-positive transgenic plants were measured in the presence of colloidal chitin, and five transgenic lines showing the highest chitinase activity were selected for checking the copy number of the transgenes through Southern blot hybridisation. Two plants carried a single copy of the transgenes, while the remainder carried either two or three copies of the transgenes. The antifungal activity of two transgenic lines that carried a single copy of the transgenes (T4 and T10) was studied by a radial diffusion assay. It was observed that the constitutive expression of these transgenes in the T4 and T10 transgenic lines suppressed the growth of S. sclerotiorum by 49 % and 47 %, respectively. The two transgenic lines were then let to self-pollinate to produce the T2 generation. Greenhouse bioassays were performed on the transgenic T2 young leaves by challenging with S. sclerotiorum and the results revealed that the expression of defensin and chimeric chitinase from a heterologous source in canola demonstrated enhanced resistance against sclerotinia stem rot disease.
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25
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Han E, Lee H. Structural effects of tachyplesin I and its linear derivative on their aggregation and mobility in lipid bilayers. J Mol Graph Model 2015; 59:123-8. [DOI: 10.1016/j.jmgm.2015.04.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 04/09/2015] [Accepted: 04/17/2015] [Indexed: 10/23/2022]
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26
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Lipsky A, Cohen A, Ion A, Yedidia I. Genetic transformation of Ornithogalum via particle bombardment and generation of Pectobacterium carotovorum-resistant plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 228:150-158. [PMID: 25438795 DOI: 10.1016/j.plantsci.2014.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 01/08/2014] [Accepted: 02/03/2014] [Indexed: 06/04/2023]
Abstract
Bacterial soft rot caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) is one of the most devastating diseases of Ornithogalum species. No effective control measures are currently available to use against this pathogen; thus, introduction of resistant genes via genetic transformation into this crop is a promising approach. Tachyplesin I, an antimicrobial peptide, has been shown to effectively control numerous pathogenic bacteria, including Pcc. In this study, liquid-grown cell clusters of Ornithogalum dubium and Ornithogalum thyrsoides were bombarded with a pCAMBIA2301 vector containing a celI leader sequence fused to a gene encoding tachyplesin I, a neomycin phosphotransferase (nptII) gene that served as a selectable marker and a β-glucuronidase (GUS) gene that served as a reporter. Selection was carried out in the dark in liquid medium containing 80mg/L kanamycin. Regeneration was executed in the light after 6-14 months depending on the cultivar. Hundreds of transgenic plantlets were produced and their identity was confirmed through GUS activity assays. PCR and RT-PCR were used to confirm the presence of the target, reporter and selection genes in the divergent lines of plantlets. The resistance of the O. dubium plants to Pcc was evaluated in vitro, following infection with a highly virulent isolate from calla lily. Although control plantlets were completely macerated within a week, 87 putative transgenic subclones displayed varying levels of disease resistance. During three growing seasons in the greenhouse, the transgenic O. dubium lines grew poorly, whereas the transgenic O. thyrsoides plants grew similarly to non-transgenic plants.
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Affiliation(s)
- Alexander Lipsky
- Department of Ornamental Horticulture, ARO, The Volcani Center, Derech Hamacabim 20, P.O. Box 6, Bet Dagan 50250, Israel
| | - Avner Cohen
- Department of Ornamental Horticulture, ARO, The Volcani Center, Derech Hamacabim 20, P.O. Box 6, Bet Dagan 50250, Israel
| | - Aurel Ion
- Department of Ornamental Horticulture, ARO, The Volcani Center, Derech Hamacabim 20, P.O. Box 6, Bet Dagan 50250, Israel
| | - Iris Yedidia
- Department of Ornamental Horticulture, ARO, The Volcani Center, Derech Hamacabim 20, P.O. Box 6, Bet Dagan 50250, Israel.
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27
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Hong J, Guan W, Jin G, Zhao H, Jiang X, Dai J. Mechanism of tachyplesin I injury to bacterial membranes and intracellular enzymes, determined by laser confocal scanning microscopy and flow cytometry. Microbiol Res 2014; 170:69-77. [PMID: 25267486 DOI: 10.1016/j.micres.2014.08.012] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Revised: 08/19/2014] [Accepted: 08/24/2014] [Indexed: 01/15/2023]
Abstract
Tachyplesin I is a 17 amino acid, cationic, antimicrobial peptide with a typical cyclic antiparallel β-sheet structure. Interactions of tachyplesin I with living bacteria are not well understood, although models have been used to elucidate how tachyplesin I permeabilizes membranes. There are several questions to be answered, such as (i) how does tachyplesin I kill bacteria after it penetrates the membrane and (ii) does bacterial death result from the inactivation of intracellular esterases as well as cell injury? In this study, the dynamic antibacterial processes of tachyplesin I and its interactions with Escherichia coli and Staphylococcus aureus were investigated using laser confocal scanning microscopy in combination with electron microscopy. The effects of tachyplesin I on E. coli cell membrane integrity, intracellular enzyme activity, and cell injury and death were investigated by flow cytometric analysis of cells following single- or double-staining with carboxyfluorescein diacetate or propidium iodide. The results of microscopy indicated that tachyplesin I kills bacteria by acting on the cell membrane and intracellular contents, with the cell membrane representing the primary target. Microscopy results also revealed that tachyplesin I uses different modes of action against E. coli and S. aureus. The results of flow cytometry showed that tachyplesin I caused E. coli cell death mainly by compromising cell membrane integrity and causing the inactivation of intracellular esterases. Flow cytometry also revealed dynamic changes in the different subpopulations of cells with increase in tachyplesin I concentrations. Bacteria exposed to 5 μg/mL of tachyplesin I did not die instantaneously; instead, they died gradually via a sublethal injury. However, upon exposure to 10-40 μg/mL of tachyplesin I, the bacteria died almost immediately. These results contribute to our understanding of the antibacterial mechanism employed by tachyplesin I.
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Affiliation(s)
- Jun Hong
- School of Applied Chemistry and Biotechnology, Shenzhen Polytechnic, Shenzhen 518055, PR China; College of Life Science and Engineering, Henan University of Urban Construction, Ping Dingshan 467036, PR China; College of Animal Science, South China Agriculture University, Guangzhou 510642, PR China.
| | - Wutai Guan
- College of Animal Science, South China Agriculture University, Guangzhou 510642, PR China.
| | - Gang Jin
- School of Applied Chemistry and Biotechnology, Shenzhen Polytechnic, Shenzhen 518055, PR China.
| | - Hongya Zhao
- School of Applied Chemistry and Biotechnology, Shenzhen Polytechnic, Shenzhen 518055, PR China.
| | - Xiaohua Jiang
- School of Applied Chemistry and Biotechnology, Shenzhen Polytechnic, Shenzhen 518055, PR China.
| | - Jianguo Dai
- School of Applied Chemistry and Biotechnology, Shenzhen Polytechnic, Shenzhen 518055, PR China.
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28
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Chen L, Li X, Gao L, Fang W. Theoretical insight into the relationship between the structures of antimicrobial peptides and their actions on bacterial membranes. J Phys Chem B 2014; 119:850-60. [PMID: 25062757 DOI: 10.1021/jp505497k] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Antimicrobial peptides with diverse cationic charges, amphiphathicities, and secondary structures possess a variety of antimicrobial activities against bacteria, fungi, and other generalized targets. To illustrate the relationship between the structures of these peptide and their actions at microscopic level, we present systematic coarse-grained dissipative particle dynamics simulations of eight types of antimicrobial peptides with different secondary structures interacting with a lipid bilayer membrane. We find that the peptides use multiple mechanisms to exert their membrane-disruptive activities: A cationic charge is essential for the peptides to selectively target negatively charged bacterial membranes. This cationic charge is also responsible for promoting electroporation. A significant hydrophobic portion is necessary to disrupt the membrane through formation of a permeable pore or translocation. Alternatively, the secondary structure and the corresponding rigidity of the peptides determine the pore structure and the translocation pathway.
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Affiliation(s)
- Licui Chen
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Xin-wai-da-jie 19#, Beijing 100875, China
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29
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Wood SJ, Park YA, Kanneganti NP, Mukkisa HR, Crisman LL, Davis SE, Vandenbosch JL, Scaglione JB, Heyl DL. Modified Cysteine-Deleted Tachyplesin (CDT) Analogs as Linear Antimicrobial Peptides: Influence of Chain Length, Positive Charge, and Hydrophobicity on Antimicrobial and Hemolytic Activity. Int J Pept Res Ther 2014. [DOI: 10.1007/s10989-014-9419-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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30
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Wiedman G, Fuselier T, He J, Searson PC, Hristova K, Wimley WC. Highly efficient macromolecule-sized poration of lipid bilayers by a synthetically evolved peptide. J Am Chem Soc 2014; 136:4724-31. [PMID: 24588399 PMCID: PMC3985440 DOI: 10.1021/ja500462s] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Indexed: 12/30/2022]
Abstract
Peptides that self-assemble, at low concentration, into bilayer-spanning pores which allow the passage of macromolecules would be beneficial in multiple areas of biotechnology. However, there are few, if any, natural or designed peptides that have this property. Here we show that the 26-residue peptide "MelP5", a synthetically evolved gain-of-function variant of the bee venom lytic peptide melittin identified in a high-throughput screen for small molecule leakage, enables the passage of macromolecules across bilayers under conditions where melittin and other pore-forming peptides do not. In surface-supported bilayers, MelP5 forms unusually high conductance, equilibrium pores at peptide:lipid ratios as low as 1:25000. The increase in bilayer conductance due to MelP5 is dramatically higher, per peptide, than the increase due to the parent sequence of melittin or other peptide pore formers. Here we also develop two novel assays for macromolecule leakage from vesicles, and we use them to characterize MelP5 pores in bilayers. We show that MelP5 allows the passage of macromolecules across vesicle membranes at peptide:lipid ratios as low as 1:500, and under conditions where neither osmotic lysis nor gross vesicle destabilization occur. The macromolecule-sized, equilibrium pores formed by MelP5 are unique as neither melittin nor other pore-forming peptides release macromolecules significantly under the same conditions. MelP5 thus appears to belong to a novel functional class of peptide that could form the foundation of multiple potential biotechnological applications.
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Affiliation(s)
- Gregory Wiedman
- Department
of Materials Science and Engineering, Johns
Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for Nanobiotechnology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Taylor Fuselier
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Jing He
- Department
of Biochemistry and Molecular Biology, Tulane
University School of Medicine, New Orleans, Louisiana 70112, United States
| | - Peter C. Searson
- Department
of Materials Science and Engineering, Johns
Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for Nanobiotechnology, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kalina Hristova
- Department
of Materials Science and Engineering, Johns
Hopkins University, Baltimore, Maryland 21218, United States
- Institute
for Nanobiotechnology, Johns Hopkins University, Baltimore, Maryland 21218, 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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31
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Pink DA, Hasan FM, Quinn BE, Winterhalter M, Mohan M, Gill TA. Interaction of protamine with gram‐negative bacteria membranes: possible alternative mechanisms of internalization in
Escherichia coli
,
Salmonella typhimurium
and
Pseudomonas aeruginosa. J Pept Sci 2014; 20:240-50. [DOI: 10.1002/psc.2610] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 11/14/2013] [Accepted: 12/02/2013] [Indexed: 11/08/2022]
Affiliation(s)
- David. A. Pink
- Department of Physics St. Francis Xavier University Antigonish NS B2G 2W5 Canada
| | - Fida M. Hasan
- Department of Process Engineering and Applied Science Dalhousie University Halifax NS B3J 2X4 Canada
| | - Bonnie E. Quinn
- Department of Physics St. Francis Xavier University Antigonish NS B2G 2W5 Canada
| | | | - Mukund Mohan
- Department of Process Engineering and Applied Science Dalhousie University Halifax NS B3J 2X4 Canada
| | - Tom A. Gill
- Department of Process Engineering and Applied Science Dalhousie University Halifax NS B3J 2X4 Canada
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32
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The MerR-like regulator BrlR impairs Pseudomonas aeruginosa biofilm tolerance to colistin by repressing PhoPQ. J Bacteriol 2013; 195:4678-88. [PMID: 23935054 DOI: 10.1128/jb.00834-13] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
While the MerR-like transcriptional regulator BrlR has been demonstrated to contribute to Pseudomonas aeruginosa biofilm tolerance to antimicrobial agents known as multidrug efflux pump substrates, the role of BrlR in resistance to cationic antimicrobial peptides (CAP), which is based on reduced outer membrane susceptibility, is not known. Here, we demonstrate that inactivation of brlR coincided with increased resistance of P. aeruginosa to colistin, while overexpression of brlR resulted in increased susceptibility. brlR expression correlated with reduced transcript abundances of phoP, phoQ, pmrA, pmrB, and arnC. Inactivation of pmrA and pmrB had no effect on the susceptibility of P. aeruginosa biofilms to colistin, while inactivation of phoP and phoQ rendered biofilms more susceptible than the wild type. The susceptibility phenotype of ΔphoP biofilms to colistin was comparable to that of P. aeruginosa biofilms overexpressing brlR. BrlR was found to directly bind to oprH promoter DNA of the oprH-phoPQ operon. BrlR reciprocally contributed to colistin and tobramycin resistance in P. aeruginosa PAO1 and CF clinical isolates, with overexpression of brlR resulting in increased tobramycin MICs and increased tobramycin resistance but decreased colistin MICs and increased colistin susceptibility. The opposite trend was observed upon brlR inactivation. The difference in susceptibility to colistin and tobramycin was eliminated by combination treatment of biofilms with both antibiotics. Our findings establish BrlR as an unusual member of the MerR family, as it not only functions as a multidrug transport activator, but also acts as a repressor of phoPQ expression, thus suppressing colistin resistance.
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33
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Dings RPM, Haseman JR, Leslie DB, Luong M, Dunn DL, Mayo KH. Bacterial membrane disrupting dodecapeptide SC4 improves survival of mice challenged with Pseudomonas aeruginosa. Biochim Biophys Acta Gen Subj 2013; 1830:3454-7. [PMID: 23403135 DOI: 10.1016/j.bbagen.2013.02.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/30/2013] [Accepted: 02/04/2013] [Indexed: 11/24/2022]
Abstract
BACKGROUND Dodecapeptide SC4 is a broad-spectrum bactericidal agent that functions by disintegrating bacterial membranes and neutralizing endotoxins. For insight into which SC4 amino acids are functionally important, we assessed Gram-negative bactericidal effects in structure-activity relationship experiments. Subsequently, SC4 was tested in a murine bacteremia model to combine and compare the efficacy with Zosyn, a first-line antibiotic against Pseudomonas aeruginosa (P. aeruginosa). METHODS SC4 alanine-scanning analogs and their activities on were tested on P. aeruginosa. Survival studies in P. aeruginosa challenged mice were executed to monitor overall efficacy of SC4 and Zosyn, as a single modality and also as combination treatment. ELISAs were used to measure blood serum levels of selected inflammatory cytokines during treatment. RESULTS Cationic residues were found to play a crucial role in terms of bactericidal activity against P. aeruginosa. In vivo, while only 9% (3/34) of control animals survived to day two and beyond, 44% (12/27) to 41% (14/34) of animals treated with SC4 or Zosyn, respectively, survived beyond one week. Combination treatment of SC4 and Zosyn demonstrated improved survival, i.e. 60% (12/20). The TNFα, IL-1, and IL-6 serum levels were attenuated in each treatment group compared to the control group. CONCLUSIONS These data show that combination treatment of SC4 and Zosyn is most effective at killing P. aeruginosa and attenuating inflammatory cytokine levels in vivo. GENERAL SIGNIFICANCE Combination treatment of SC4 and Zosyn may be useful in the clinic as a more effective antibiotic therapy against Gram-negative infectious diseases.
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Affiliation(s)
- Ruud P M Dings
- Department of Biochemistry, University of Minnesota Health Science Center, Minneapolis, MN 55455, USA
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34
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Cathelicidin antimicrobial peptide expression is not induced or required for bacterial clearance during salmonella enterica infection of human monocyte-derived macrophages. Infect Immun 2012; 80:3930-8. [PMID: 22927052 DOI: 10.1128/iai.00672-12] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Salmonella enterica serovar Typhimurium is able to resist antimicrobial peptide killing by induction of the PhoP-PhoQ and PmrA-PmrB two-component systems and the lipopolysaccharide (LPS) modifications they mediate. Murine cathelin-related antimicrobial peptide (CRAMP) has been reported to inhibit S. Typhimurium growth in vitro and in vivo. We hypothesize that infection of human monocyte-derived macrophages (MDMs) with Salmonella enterica serovar Typhi and S. Typhimurium will induce human cathelicidin antimicrobial peptide (CAMP) production, and exposure to LL-37 (processed, active form of CAMP/hCAP18) will lead to upregulation of PmrAB-mediated LPS modifications and increased survival in vivo. Unlike in mouse macrophages, in which CRAMP is upregulated during infection, camp gene expression was not induced in human MDMs infected with S. Typhi or S. Typhimurium. Upon infection, intracellular levels of ΔphoPQ, ΔpmrAB, and PhoP(c) S. Typhi decreased over time but were not further inhibited by the vitamin D(3)-induced increase in camp expression. MDMs infected with wild-type (WT) S. Typhi or S. Typhimurium released similar levels of proinflammatory cytokines; however, the LPS modification mutant strains dramatically differed in MDM-elicited cytokine levels. Overall, these findings indicate that camp is not induced during Salmonella infection of MDMs nor is key to Salmonella intracellular clearance. However, the cytokine responses from MDMs infected with WT or LPS modification mutant strains differ significantly, indicating a role for LPS modifications in altering the host inflammatory response. Our findings also suggest that S. Typhi and S. Typhimurium elicit different proinflammatory responses from MDMs, despite being capable of adding similar modifications to their LPS structures.
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35
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Richards SM, Strandberg KL, Conroy M, Gunn JS. Cationic antimicrobial peptides serve as activation signals for the Salmonella Typhimurium PhoPQ and PmrAB regulons in vitro and in vivo. Front Cell Infect Microbiol 2012; 2:102. [PMID: 22919691 PMCID: PMC3417628 DOI: 10.3389/fcimb.2012.00102] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 07/06/2012] [Indexed: 02/06/2023] Open
Abstract
Salmonella enterica serovar Typhimurium uses two-component regulatory systems (TCRSs) to respond to environmental stimuli. Upon infection, the TCRSs PhoP-PhoQ (PhoPQ) and PmrA-PmrB (PmrAB) are activated by environmental signals detected in the lumen of the intestine and within host cells. TCRS-mediated gene expression leads to upregulation of genes involved in lipopolysaccharide (LPS) modification and cationic antimicrobial peptide (CAMP) resistance. This research expands on previous studies which have shown that CAMPs can activate Salmonella TCRSs in vitro. The focus of this work was to determine if CAMPs can act as environmental signals for PhoPQ- and PmrAB-mediated gene expression in vitro, during infection of macrophages and in a mouse model of infection. Monitoring of PhoPQ and PmrAB activation using recombinase-based in vivo expression technology (RIVET), alkaline phosphtase and β-galactosidase reporter fusion constructs demonstrated that S. Typhimurium PhoQ can sense CAMPs in vitro. In mouse macrophages, the cathelecidin CRAMP does not activate the PhoPQ regulon. Acidification of the Salmonella-containing vacuole activates PhoP- and PmrA-regulated loci but blocking acidification still does not reveal a role for CRAMP in TCRS activation in mouse macrophages. However, assays performed in susceptible wild type (WT), CRAMP knockout (KO), and matrilysin (a metalloproteinase necessary for activating murine α-defensins) KO mice suggest CRAMP, but not α-defensins, serve as a putative direct TCRS activation signal in the mouse intestine. These studies provide a better understanding of the in vivo environments that result in activation of these virulence-associated TCRSs.
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Affiliation(s)
- Susan M Richards
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, The Ohio State University, Columbus OH, USA
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36
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Sharma S, Sethi S, Prasad R, Samanta P, Rajwanshi A, Malhotra S, Sharma M. Characterization of low molecular weight antimicrobial peptide from human female reproductive tract. Indian J Med Res 2012; 134:679-87. [PMID: 22199108 PMCID: PMC3249967 DOI: 10.4103/0971-5916.90996] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Background & objectives: The mechanisms that protect female upper genital tract from ascending infection by microbes present in vagina are only partially understood. It is expected that epithelial cells in mucosal surfaces and their secretions directly interfere with microbial colonization and invasion. This study was aimed to demonstrate the expression of 2 kDa antimicrobial peptide which was identified and purified from female genital tract tissues using chromatographic techniques. Methods: Low molecular weight proteins were isolated from human female reproductive tract tissues obtained from premenopausal women. Antimicrobial activity of these LMW proteins was assessed against different reproductive tract pathogens viz., Neisseria gonorrhoeae, Group B streptococcus, Gardnerella vaginalis, Escherechia coli and Candida albicans. The expression of these peptides were also documented in reproductive tract tissues with the help of hyperimmune sera raised against the rabbits. The purified peptide was characterized by N-terminal sequencing. Results: Immunohistochemical and immunofluorescence studies demonstrated that 2 kDa peptide was expressed in the stratified squamous epithelial cells of the ectocervix while it was absent in columnar epithelial cells of upper genital tract. Upregulation of the expression of this peptide was observed in patients of chronic non-specific cervicitis and acute on chronic cervicitis. This purified antimicrobial peptide also showed broad spectrum antimicrobial activity against different reproductive tract pathogens. Interpretation & conclusions: Considering the emerging bacterial resistance against conventional antibiotics, isolation and understanding of the expression of antimicrobial peptides from female reproductive tissue extracts may provide some leads towards the development of strategies for the treatment of reproductive tract infections.
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Affiliation(s)
- Sarita Sharma
- Department of Medical Microbiology, Postgraduate Institute of Medical Education & Research, Chandigarh, India
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37
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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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38
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Pasupuleti M, Schmidtchen A, Malmsten M. Antimicrobial peptides: key components of the innate immune system. Crit Rev Biotechnol 2011; 32:143-71. [PMID: 22074402 DOI: 10.3109/07388551.2011.594423] [Citation(s) in RCA: 499] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Life-threatening infectious diseases are on their way to cause a worldwide crisis, as treating them effectively is becoming increasingly difficult due to the emergence of antibiotic resistant strains. Antimicrobial peptides (AMPs) form an ancient type of innate immunity found universally in all living organisms, providing a principal first-line of defense against the invading pathogens. The unique diverse function and architecture of AMPs has attracted considerable attention by scientists, both in terms of understanding the basic biology of the innate immune system, and as a tool in the design of molecular templates for new anti-infective drugs. AMPs are gene-encoded short (<100 amino acids), amphipathic molecules with hydrophobic and cationic amino acids arranged spatially, which exhibit broad spectrum antimicrobial activity. AMPs have been the subject of natural evolution, as have the microbes, for hundreds of millions of years. Despite this long history of co-evolution, AMPs have not lost their ability to kill or inhibit the microbes totally, nor have the microbes learnt to avoid the lethal punch of AMPs. AMPs therefore have potential to provide an important breakthrough and form the basis for a new class of antibiotics. In this review, we would like to give an overview of cationic antimicrobial peptides, origin, structure, functions, and mode of action of AMPs, which are highly expressed and found in humans, as well as a brief discussion about widely abundant, well characterized AMPs in mammals, in addition to pharmaceutical aspects and the additional functions of AMPs.
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Affiliation(s)
- Mukesh Pasupuleti
- Department of Microbiology and Immunology, Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, Canada.
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39
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Rotstein BH, Mourtada R, Kelley SO, Yudin AK. Solvatochromic reagents for multicomponent reactions and their utility in the development of cell-permeable macrocyclic peptide vectors. Chemistry 2011; 17:12257-61. [PMID: 21932287 DOI: 10.1002/chem.201102096] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Indexed: 01/05/2023]
Affiliation(s)
- Benjamin H Rotstein
- Department of Chemistry, University of Toronto, Toronto, ON, M5H 3H5, Canada
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40
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RAHMAN MM, TSUJI N, BOLDBAATAR D, BATTUR B, LIAO M, UMEMIYA-SHIRAFUJI R, YOU M, TANAKA T, FUJISAKI K. Structural Characterization and Cytolytic Activity of a Potent Antimicrobial Motif in Longicin, a Defensin-Like Peptide in the Tick Haemaphysalis longicornis. J Vet Med Sci 2010; 72:149-56. [DOI: 10.1292/jvms.09-0167] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
| | - Naotoshi TSUJI
- National Institute of Animal Health, National Agricultural Research Organization
| | | | - Banzragch BATTUR
- Department of Frontier Veterinary Medicine, Kagoshima University
| | - Min LIAO
- Department of Frontier Veterinary Medicine, Kagoshima University
| | | | - Myungjo YOU
- Department of Veterinary Parasitology, College of Veterinary Medicine, Chonbuk National University
| | - Tetsuya TANAKA
- Department of Frontier Veterinary Medicine, Kagoshima University
| | - Kozo FUJISAKI
- Department of Frontier Veterinary Medicine, Kagoshima University
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41
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Strauss J, Kadilak A, Cronin C, Mello CM, Camesano TA. Binding, inactivation, and adhesion forces between antimicrobial peptide cecropin P1 and pathogenic E. coli. Colloids Surf B Biointerfaces 2010; 75:156-64. [DOI: 10.1016/j.colsurfb.2009.08.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Revised: 07/20/2009] [Accepted: 08/17/2009] [Indexed: 10/20/2022]
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42
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A defensin with highly potent antipathogenic activities from the seeds of purple pole bean. Biosci Rep 2009; 30:101-9. [PMID: 19335335 DOI: 10.1042/bsr20090004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A 5443 Da peptide with sequence homology to defensins was purified from purple pole beans (Phaseolus vulgaris cv. 'Extra-long Purple Pole bean'). This peptide was isolated by adsorption on an affinity chromatographic medium Affi-Gel Blue gel and ion-exchange chromatographic media SP-Sepharose (sulfopropyl-Sepharose) and Mono S and by gel filtration on Superdex peptide. The peptide inhibited mycelial growth in Mycosphaerella arachidicola, Helminthosporium maydis, Fusarium oxysporum, Verticillium dahliae, Rhizoctonia solani, Candida albicans and Setosphaeria turcica with an IC50 of 0.8, 0.9, 2.3, 3.2, 4.3, 4.8 and 9.8 microM respectively. Its antifungal potency was higher than that of the plant defensin coccinin (IC50>50 microM). It induced membrane permeabilization in C. albicans as evidenced by SYTOX Green uptake, but did not affect erythrocyte membrane permeability. It inhibited growth in M. arachidicola by inducing chitin accumulation at hyphal tips as was shown by Congo Red staining. The antifungal activity was pH stable and thermostable. The peptide inhibited the proliferation of hepatoma (HepG2), breast cancer (MCF7), colon cancer (HT29) and cervical cancer (SiHa) cells but not that of human embryonic liver (WRL68) cells. Its anti-HepG2 activity (IC50=4.1+/-0.8 microM, n=3) was higher than that of another plant defensin, gymnin (IC50>50 microM). Its anti-MCF7 activity (IC50=8.3+/-0.3 microM, n=3) was similar to that of other plant defensins. It reduced the activity of HIV-1 reverse transcriptase with an IC50 of 0.5+/-0.1 microM, n=3, much more potently than other plant defensins (IC50>40 microM). There is the possibility of using the purple pole bean defensin for producing antifungal drugs and/or transgenic plants with fungal resistance.
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Duchardt F, Ruttekolk IR, Verdurmen WPR, Lortat-Jacob H, Bürck J, Hufnagel H, Fischer R, van den Heuvel M, Löwik DWPM, Vuister GW, Ulrich A, de Waard M, Brock R. A cell-penetrating peptide derived from human lactoferrin with conformation-dependent uptake efficiency. J Biol Chem 2009; 284:36099-36108. [PMID: 19858187 DOI: 10.1074/jbc.m109.036426] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The molecular events that contribute to the cellular uptake of cell-penetrating peptides (CPP) are still a matter of intense research. Here, we report on the identification and characterization of a 22-amino acid CPP derived from the human milk protein, lactoferrin. The peptide exhibits a conformation-dependent uptake efficiency that is correlated with efficient binding to heparan sulfate and lipid-induced conformational changes. The peptide contains a disulfide bridge formed by terminal cysteine residues. At concentrations exceeding 10 mum, this peptide undergoes the same rapid entry into the cytoplasm that was described previously for the arginine-rich CPPs nona-arginine and Tat. Cytoplasmic entry strictly depends on the presence of the disulfide bridge. To better understand this conformation dependence, NMR spectroscopy was performed for the free peptide, and CD measurements were performed for free and lipid-bound peptide. In solution, the peptides showed only slight differences in secondary structure, with a predominantly disordered structure both in the presence and absence of the disulfide bridge. In contrast, in complex with large unilamellar vesicles, the conformation of the oxidized and reduced forms of the peptide clearly differed. Moreover, surface plasmon resonance experiments showed that the oxidized form binds to heparan sulfate with a considerably higher affinity than the reduced form. Consistently, membrane binding and cellular uptake of the peptide were reduced when heparan sulfate chains were removed.
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Affiliation(s)
- Falk Duchardt
- Interfaculty Institute for Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Ivo R Ruttekolk
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen, The Netherlands
| | - Wouter P R Verdurmen
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen, The Netherlands
| | - Hugues Lortat-Jacob
- Institut de Biologie Structurale, UMR 5075 CEA-CNRS, Université Joseph Fourier, 41 rue Jules Horowitz, 38027 Grenoble Cedex 1, France
| | - Jochen Bürck
- Karlsruhe Institute of Technology, Forschungszentrum Karlsruhe, IBG-2, 76131 Karlsruhe, Germany
| | - Hansjörg Hufnagel
- Interfaculty Institute for Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Rainer Fischer
- Interfaculty Institute for Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Maaike van den Heuvel
- Department of Bio-Organic Chemistry, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Dennis W P M Löwik
- Department of Bio-Organic Chemistry, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Geerten W Vuister
- Department of Protein Biophysics, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Anne Ulrich
- Karlsruhe Institute of Technology, Forschungszentrum Karlsruhe, IBG-2, 76131 Karlsruhe, Germany
| | - Michel de Waard
- INSERM U836, Université Joseph Fourier, Grenoble Neuroscience Institute, Group 3, 38027 Grenoble Cedex 1, France
| | - Roland Brock
- Interfaculty Institute for Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany; Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen, The Netherlands.
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44
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Abstract
There is widespread acceptance that cationic antimicrobial peptides, apart from their membrane-permeabilizing/disrupting properties, also operate through interactions with intracellular targets, or disruption of key cellular processes. Examples of intracellular activity include inhibition of DNA and protein synthesis, inhibition of chaperone-assisted protein folding and enzymatic activity, and inhibition of cytoplasmic membrane septum formation and cell wall synthesis. The purpose of this minireview is to question some widely held views about intracellular-targeting antimicrobial peptides. In particular, I focus on the relative contributions of intracellular targeting and membrane disruption to the overall killing strategy of antimicrobial peptides, as well as on mechanisms whereby some peptides are able to translocate spontaneously across the plasma membrane. Currently, there are no more than three peptides that have been convincingly demonstrated to enter microbial cells without the involvement of stereospecific interactions with a receptor/docking molecule and, once in the cell, to interfere with cellular functions. From the limited data currently available, it seems unlikely that this property, which is isolated in particular peptide families, is also shared by the hundreds of naturally occurring antimicrobial peptides that differ in length, amino acid composition, sequence, hydrophobicity, amphipathicity, and membrane-bound conformation. Microbial cell entry and/or membrane damage associated with membrane phase/transient pore or long-lived transitions could be a feature common to intracellular-targeting antimicrobial peptides and mammalian cell-penetrating peptides that have an overrepresentation of one or two amino acids, i.e. Trp and Pro, His, or Arg. Differences in membrane lipid composition, as well as differential lipid recruitment by peptides, may provide a basis for microbial cell killing on one hand, and mammalian cell passage on the other.
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Affiliation(s)
- Pierre Nicolas
- Biogenèse des Signaux Peptidiques, ER3-UPMC, Université Pierre et Marie Curie, Paris, France.
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45
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Yokoyama S, Iida Y, Kawasaki Y, Minami Y, Watanabe K, Yagi F. The chitin-binding capability of Cy-AMP1 from cycad is essential to antifungal activity. J Pept Sci 2009; 15:492-7. [PMID: 19466694 DOI: 10.1002/psc.1147] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Antimicrobial peptides are important components of the host innate immune responses by exerting broad-spectrum microbicidal activity against pathogenic microbes. Cy-AMP1 found in the cycad (Cycas revoluta) seeds has chitin-binding ability, and the chitin-binding domain was conserved in knottin-type and hevein-type antimicrobial peptides. The recombinant Cy-AMP1 was expressed in Escherichia coli and purified to study the role of chitin-binding domain. The mutants of Cy-AMP1 lost chitin-binding ability completely, and its antifungal activity was markedly decreased in comparison with native Cy-AMP1. However, the antimicrobial activities of the mutant peptides are nearly identical to that of native one. It was suggested that the chitin-binding domain plays an essential role in antifungal, but not antimicrobial, activity of Cy-AMP1.
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Affiliation(s)
- Seiya Yokoyama
- Department of Applied Biological Chemistry, The United Graduate School of Agricultural Sciences, Kagoshima University, 1-21-24, Korimoto, Kagoshima, 890-0065, Japan
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46
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Hao G, Shi YH, Tang YL, Le GW. The membrane action mechanism of analogs of the antimicrobial peptide Buforin 2. Peptides 2009; 30:1421-7. [PMID: 19467281 DOI: 10.1016/j.peptides.2009.05.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2009] [Revised: 05/15/2009] [Accepted: 05/15/2009] [Indexed: 10/20/2022]
Abstract
Previously, the antimicrobial peptides BF2-A and BF2-B, two analogs of Buforin 2 that was hypothesized to kill bacteria by entering cells and binding nucleic acids, had been designed based on the structure-activity analysis of Buforin 2. In the present study, BF2-A and BF2-B were chemically synthesized and their activities and lipopolysaccharide affinity were assayed. To elucidate the mechanism of action with cytoplasmic membranes, we subsequently examined the membrane permeability of both peptides in detail. Both peptides showed stronger antimicrobial activities against a broad spectrum of microorganisms than their parent peptide. Interestingly, BF2-A did not cause significant membrane permeabilization for influx of ONPG into cells, and hardly caused the leakage of intracellular macromolecules, probably BF2-A slightly disturbed cell membrane causing the K(+) leakage during peptide crossing phospholipids bilayer. Electron micrographs indicated that the cell membrane treated by BF2-A was still intact within 20min. On the contrary, BF2-B obviously increased the outer and inner membrane permeability, even induced the slight leakage of macromolecules in the cytoplasm. The leakage of cytoplasmic contents was also demonstrated by the electron micrographs. The increase of membrane permeabilization explained why BF2-B displayed better antimicrobial activity and rapid killing kinetics than BF2-A.
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Affiliation(s)
- Gang Hao
- The State Key Laboratory of Food Science and Technology, JiangNan University, Wuxi, 214122, Jiangsu Province, China
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47
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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.
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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
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48
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Hadjicharalambous C, Sheynis T, Jelinek R, Shanahan MT, Ouellette AJ, Gizeli E. Mechanisms of alpha-defensin bactericidal action: comparative membrane disruption by Cryptdin-4 and its disulfide-null analogue. Biochemistry 2009; 47:12626-34. [PMID: 18973303 DOI: 10.1021/bi800335e] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mammalian alpha-defensins all have a conserved triple-stranded beta-sheet structure that is constrained by an invariant tridisulfide array, and the peptides exert bactericidal effects by permeabilizing the target cell envelope. Curiously, the disordered, disulfide-null variant of mouse alpha-defensin cryptdin-4 (Crp4), termed (6C/A)-Crp4, has bactericidal activity equal to or greater than that of the native peptide, providing a rationale for comparing the mechanisms by which the peptides interact with and disrupt phospholipid vesicles of defined composition. For both live Escherichia coli ML35 cells and model membranes, disordered (6C/A)-Crp4 induced leakage in a manner similar to that of Crp4 but had less overall membrane permeabilizing activity. Crp4 induction of the leakage of the fluorophore from electronegative liposomes was strongly dependent on vesicle lipid charge and composition, and the incorporation of cardiolipin into liposomes of low electronegative charge to mimic bacterial membrane composition conferred sensitivity to Crp4- and (6C/A)-Crp4-mediated vesicle lysis. Membrane perturbation studies using biomimetic lipid/polydiacetylene vesicles showed that Crp4 inserts more pronouncedly into membranes containing a high fraction of electronegative lipids or cardiolipin than (6C/A)-Crp4 does, correlating directly with measurements of induced leakage. Fluorescence resonance energy transfer experiments provided evidence that Crp4 translocates across highly charged or cardiolipin-containing membranes, in a process coupled with membrane permeabilization, but (6C/A)-Crp4 did not translocate across lipid bilayers and consistently displayed membrane surface association. Thus, despite the greater in vitro bactericidal activity of (6C/A)-Crp4, native, beta-sheet-containing Crp4 induces membrane permeabilization more effectively than disulfide-null Crp4 by translocating and forming transient membrane defects. (6C/A)-Crp4, on the other hand, appears to induce greater membrane disintegration.
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Affiliation(s)
- Chrystalleni Hadjicharalambous
- Institute of Molecular Biology and Biotechnology, FORTH, and Department of Biology, University of Crete, Heraklion, Crete, Greece
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49
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Protopapa E, Maude S, Aggeli A, Nelson A. Interaction of self-assembling beta-sheet peptides with phospholipid monolayers: the role of aggregation state, polarity, charge and applied field. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:3289-96. [PMID: 19437790 DOI: 10.1021/la803368r] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Studies of beta-sheet peptide/phospholipid interactions are important for an understanding of the folding of beta-sheet-rich membrane proteins and the action of antimicrobial and toxic peptides. Further, self-assembling peptides have numerous applications in medicine and therefore an insight is required into the relation between peptide molecular structure and biomembrane activity. We previously developed one of the simplest known model peptide systems which, above a critical concentration (c*) in solution, undergoes nucleated one-dimensional self-assembly from a monomeric random coil into a hierarchy of well defined beta-sheet structures. Here we examine the effects of peptide aggregation, polarity, charge, and applied field on peptide interactions with dioleoyl phosphatidylcholine (DOPC) monolayers using electrochemical techniques. The interactions of six systematically altered 11 residue beta-sheet tape-forming peptides were investigated. The following findings with respect to 11 residue beta-sheet peptide-DOPC interaction arose from the study: (i) The solution monomer peptide species is the monolayer active moeity. (ii) Amphiphilic peptides are more monolayer active than polar peptides in the absence of applied electric field. (iii) Positive charge on amphiphilic peptides facilitates monolayer interaction in the absence of applied electric field. (iv) Negative applied electric field facilitates monolayer interaction with positively charged amphiphilic and polar peptides. (v) Neutral amphiphilic peptides permeabilize DOPC layers to ions to the greatest extent. (vi) The beta-sheet tape forming peptides are shown to be significantly less monolayer disruptive than antimicrobial peptides. These conclusions will greatly contribute to the rational design of new peptide-based biomaterials and biosensors.
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Affiliation(s)
- Elisabeth Protopapa
- Centre for Self-Organising Molecular Systems (SOMS), School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
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50
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Wong J, Hao J, Cao Z, Qiao M, Xu H, Bai Y, Ng T. An antifungal protein fromBacillus amyloliquefaciens. J Appl Microbiol 2008; 105:1888-98. [DOI: 10.1111/j.1365-2672.2008.03917.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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