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Malec K, Monaco S, Delso I, Nestorowicz J, Kozakiewicz-Latała M, Karolewicz B, Khimyak YZ, Angulo J, Nartowski KP. Unravelling the mechanisms of drugs partitioning phenomena in micellar systems via NMR spectroscopy. J Colloid Interface Sci 2023; 638:135-148. [PMID: 36736115 DOI: 10.1016/j.jcis.2023.01.063] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/12/2023] [Indexed: 01/22/2023]
Abstract
Despite extensive use of micelles in materials and colloidal science, their supramolecular organization as well as host-guest interactions within these dynamic assemblies are poorly understood. Small guest molecules in the presence of micelles undergo constant exchange between a micellar aggregate and the surrounding solution, posing a considerable challenge for their molecular level characterisation. In this work we reveal the interaction maps between small guest molecules and surfactants forming micelles via novel applications of NMR techniques supported with state-of-the-art analytical methods used in colloidal science. Model micelles composed of structurally distinct surfactants (block non-ionic polymer Pluronic® F-127, non-ionic surfactant Tween 20 or Tween 80, and ionic surfactant sodium lauryl sulphate, SLS) were selected and loaded with model small molecules of biological relevance (i.e. the drugs fluconazole, FLU or indomethacin, IMC) known to have different partition coefficients. Molecular level organization of FLU or IMC within hydrophilic and hydrophobic domains of micellar aggregates was established using the combination of NMR methods (1D 1H NMR, 1D 19F NMR, 2D 1H-1H NOESY and 2D 1H-19F HOESY, and the multifrequency-STD NMR) and corroborated with molecular dynamics (MD) simulations. This is the first application of multifrequency-STD NMR to colloidal systems, enabling us to elucidate intricately detailed patterns of drug/micelle interactions in a single NMR experiment within minutes. Importantly, our results indicate that flexible surfactants, such as block copolymers and polysorbates, form micellar aggregates with a surface composed of both hydrophilic and hydrophobic domains and do not follow the classical core-shell model of the micelle. We propose that the magnitude of changes in 1H chemical shifts corroborated with interaction maps obtained from DEEP-STD NMR and 2D NMR experiments can be used as an indicator of the strength of the guest-surfactant interactions. This NMR toolbox can be adopted for the analysis of broad range of colloidal host-guest systems from soft materials to biological systems.
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Affiliation(s)
- Katarzyna Malec
- Department of Drug Form Technology, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska Str, 50-556 Wroclaw, Poland
| | - Serena Monaco
- School of Pharmacy, University of East Anglia, Chancellors Drive, NR4 7TJ Norwich, UK
| | - Ignacio Delso
- School of Pharmacy, University of East Anglia, Chancellors Drive, NR4 7TJ Norwich, UK
| | - Justyna Nestorowicz
- Department of Drug Form Technology, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska Str, 50-556 Wroclaw, Poland
| | - Marta Kozakiewicz-Latała
- Department of Drug Form Technology, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska Str, 50-556 Wroclaw, Poland
| | - Bożena Karolewicz
- Department of Drug Form Technology, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska Str, 50-556 Wroclaw, Poland
| | - Yaroslav Z Khimyak
- School of Pharmacy, University of East Anglia, Chancellors Drive, NR4 7TJ Norwich, UK.
| | - Jesús Angulo
- School of Pharmacy, University of East Anglia, Chancellors Drive, NR4 7TJ Norwich, UK; Instituto de Investigaciones Químicas (CSIC-US), Avda. Américo Vespucio, 49, Sevilla 41092, Spain.
| | - Karol P Nartowski
- Department of Drug Form Technology, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska Str, 50-556 Wroclaw, Poland; School of Pharmacy, University of East Anglia, Chancellors Drive, NR4 7TJ Norwich, UK.
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Temporins: Multifunctional Peptides from Frog Skin. Int J Mol Sci 2023; 24:ijms24065426. [PMID: 36982501 PMCID: PMC10049141 DOI: 10.3390/ijms24065426] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/03/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023] Open
Abstract
Temporins are short peptides secreted by frogs from all over the world. They exert antimicrobial activity, mainly against Gram-positive bacteria, including resistant pathogens; recent studies highlight other possible applications of these peptides as anticancer or antiviral agents. This review is meant to describe the main features of temporins produced by different ranid genera. Due to the abundance of published papers, we focus on the most widely investigated peptides. We report studies on their mechanism of action and three-dimensional structure in model systems mimicking bacterial membranes or in the presence of cells. The design and the antimicrobial activity of peptide analogues is also described, with the aim of highlighting elements that are crucial to improve the bioactivity of peptides while reducing their toxicity. Finally, a short section is dedicated to the studies aimed at applying these peptides as drugs, to produce new antimicrobial materials or in other technological uses.
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Iram D, Kindarle UA, Sansi MS, Meena S, Puniya AK, Vij S. Peptidomics-based identification of an antimicrobial peptide derived from goat milk fermented by Lactobacillus rhamnosus (C25). J Food Biochem 2022; 46:e14450. [PMID: 36226982 DOI: 10.1111/jfbc.14450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/03/2022] [Accepted: 09/20/2022] [Indexed: 01/14/2023]
Abstract
Antimicrobial peptides (AMPs) are emerging as promising novel drug applicants. In the present study, goat milk was fermented using Lactobacillus rhamnosus C25 to generate bioactive peptides (BAPs). The peptide fractions generated were separated using ultrafiltration membranes with molecular weight cut-offs of 3, 5, and 10 kDa, and their antimicrobial activity toward Gram-positive and Gram-negative bacteria was investigated. Isolated AMPs were characterized using RP-HPLC and identified by LC-MS/MS. A total of 569 sequences of peptides were identified by mass spectrometry. Out of the 569, 36 were predicted as AMPs, 21 were predicted as cationic, and out of 21, 6 AMPs were helical peptides. In silico analysis indicated that the majority of peptides were antimicrobial and cationic in nature, an important factor for peptide interaction with the negative charge membrane of bacteria. The results showed that the peptides of <5 kDa exhibited maximum antibacterial activity against E. faecalis, E. coli, and S. typhi. Further, molecular docking was used to evaluate the potent MurD ligase inhibitors. On the basis of ligand binding energy, six predicted AMPs were selected and then analyzed by AutoDock tools. Among the six AMPs, peptides IGHFKLIFSLLRV (-7.5 kcal/mol) and KSFCPAPVAPPPPT (-7.6 kcal/mol), were predicted as a high-potent antimicrobial. Based on these findings, in silico investigations reveal that proteins of goat milk are a potential source of AMPs. This is for the first time that the antimicrobial peptides produced by Lactobacillus rhamnosus (C25) fermentation of goat milk have been identified via LC-MS/MS and predicted as AMPs, cationic charges, helical structure in nature, and potent MurD ligase inhibitors. These peptides can be synthesized and improved for use as antimicrobial agents. PRACTICAL APPLICATIONS: Goat milk is considered a high-quality source of milk protein. According to this study, goat milk protein is a potential source of AMPs, Fermentation can yield goat milk-derived peptides with a broad antibacterial activity spectrum at a low cost. The approach described here could be beneficial in that the significant AMPs can be synthesized and used in the pharmaceutical and food industries.
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Affiliation(s)
- Daraksha Iram
- Antimicrobial Peptides, Biofunctional Probiotics & Peptidomics Laboratory, Dairy Microbiology Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Uday Arun Kindarle
- Antimicrobial Peptides, Biofunctional Probiotics & Peptidomics Laboratory, Dairy Microbiology Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Manish Singh Sansi
- Biofunctional Peptidomics & Metabolic Syndrome Laboratory, Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Sunita Meena
- Biofunctional Peptidomics & Metabolic Syndrome Laboratory, Animal Biochemistry Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Anil Kumar Puniya
- Anaerobic Microbial Fermentation Laboratory, Dairy Microbiology Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Shilpa Vij
- Antimicrobial Peptides, Biofunctional Probiotics & Peptidomics Laboratory, Dairy Microbiology Division, ICAR-National Dairy Research Institute, Karnal, India
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Lin Y, Lin T, Cheng N, Wu S, Huang J, Chen X, Chen T, Zhou M, Wang L, Shaw C. Evaluation of antimicrobial and anticancer activities of three peptides identified from the skin secretion of Hylarana latouchii. Acta Biochim Biophys Sin (Shanghai) 2021; 53:1469-1483. [PMID: 34508563 DOI: 10.1093/abbs/gmab126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Indexed: 12/22/2022] Open
Abstract
The skins of frogs of the family Ranidae are particularly rich sources of biologically active peptides, among which antimicrobial peptides (AMPs) constitute the major portion. Some of these have attracted the interest of researchers because they possess both antimicrobial and anticancer activities. In this study, with 'shotgun' cloning and MS/MS fragmentation, three AMPs, homologues of family brevinin-1 (brevinin-1HL), and temporin (temporin-HLa and temporin-HLb), were discovered from the skin secretion of the broad-folded frog, Hylarana latouchii. They exhibited various degrees of antimicrobial and antibiofilm activities against test microorganisms and hemolysis on horse erythrocytes. It was found that they could induce bacteria death through disrupting cell membranes and binding to bacterial DNA. In addition, they also showed different potencies towards human cancer cell lines. The secondary structure and physicochemical properties of each peptide were investigated to preliminarily reveal their structure-activity relationships. Circular dichroism spectrometry showed that they all adopted a canonical α-helical conformation in membrane-mimetic solvents. Notably, the prepropeptide of brevinin-1HL from H. latouchii was highly identical to that of brevinin-1GHd from Hylarana guentheri, indicating a close relationship between these two species. Accordingly, this study provides candidates for the design of novel anti-infective and antineoplastic agents to fight multidrug-resistant bacteria and malignant tumors and also offers additional clues for the taxonomy of ranid frogs.
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Affiliation(s)
- Yan Lin
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Natural Drug Discovery Group, School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK
| | - Tianxing Lin
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Ningna Cheng
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shuting Wu
- College of Chemistry, Fuzhou University, Fuzhou 350108, China
| | - Jiancai Huang
- College of Chemistry, Fuzhou University, Fuzhou 350108, China
| | - Xiaoling Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK
| | - Tianbao Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK
| | - Mei Zhou
- Natural Drug Discovery Group, School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK
| | - Lei Wang
- Natural Drug Discovery Group, School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK
| | - Chris Shaw
- Natural Drug Discovery Group, School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK
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Zai Y, Xi X, Ye Z, Ma C, Zhou M, Chen X, Siu SWI, Chen T, Wang L, Kwok HF. Aggregation and Its Influence on the Bioactivities of a Novel Antimicrobial Peptide, Temporin-PF, and Its Analogues. Int J Mol Sci 2021; 22:4509. [PMID: 33925935 PMCID: PMC8123395 DOI: 10.3390/ijms22094509] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 02/07/2023] Open
Abstract
Temporin is an antimicrobial peptide (AMP) family discovered in the skin secretion of ranid frog that has become a promising alternative for conventional antibiotic therapy. Herein, a novel temporin peptide, Temporin-PF (TPF), was successfully identified from Pelophylax fukienensis. It exhibited potent activity against Gram-positive bacteria, but no effect on Gram-negative bacteria. Additionally, TPF exhibited aggregation effects in different solutions. Three analogs were further designed to study the relationship between the aggregation patterns and bioactivities, and the MD simulation was performed for revealing the pattern of the peptide assembly. As the results showed, all peptides were able to aggregate in the standard culture media and salt solutions, especially CaCl2 and MgCl2 buffers, where the aggregation was affected by the concentration of the salts. MD simulation reported that all peptides were able to form oligomers. The parent peptide assembly depended on the hydrophobic interaction via the residues in the middle domain of the sequence. However, the substitution of Trp/D-Trp resulted in an enhanced inter-peptide interaction in the zipper-like domain and eliminated overall biological activities. Our study suggested that introducing aromaticity at the zipper-like domain for temporin may not improve the bioactivities, which might be related to the formation of aggregates via the inter-peptide contacts at the zipper-like motif domain, and it could reduce the binding affinity to the lipid membrane of microorganisms.
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Affiliation(s)
- Yu Zai
- Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Avenida da Univesidade, Taipa, Macau, China;
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
- Jiangsu Key Laboratory of Biofunctional Molecule, College of Life Sciences and Chemistry, Jiangsu Second Normal University, Nanjing 210013, China
| | - Xinping Xi
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Zhuming Ye
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Chengbang Ma
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Mei Zhou
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Xiaoling Chen
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Shirley W. I. Siu
- Department of Computer and Information Science, Faculty of Science and Technology, University of Macau, Avenida da Universidade, Taipa, Macau, China;
| | - Tianbao Chen
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Lei Wang
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Z.Y.); (C.M.); (M.Z.); (X.C.); (T.C.); (L.W.)
| | - Hang Fai Kwok
- Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Avenida da Univesidade, Taipa, Macau, China;
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Dash R, Bhattacharjya S. Thanatin: An Emerging Host Defense Antimicrobial Peptide with Multiple Modes of Action. Int J Mol Sci 2021; 22:ijms22041522. [PMID: 33546369 PMCID: PMC7913509 DOI: 10.3390/ijms22041522] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 01/28/2021] [Accepted: 02/01/2021] [Indexed: 12/11/2022] Open
Abstract
Antimicrobial peptides (AMPs) possess great potential for combating drug-resistant bacteria. Thanatin is a pathogen-inducible single-disulfide-bond-containing β-hairpin AMP which was first isolated from the insect Podisus maculiventris. The 21-residue-long thanatin displays broad-spectrum activity against both Gram-negative and Gram-positive bacteria as well as against various species of fungi. Remarkably, thanatin was found to be highly potent in inhibiting the growth of bacteria and fungi at considerably low concentrations. Although thanatin was isolated around 25 years ago, only recently has there been a pronounced interest in understanding its mode of action and activity against drug-resistant bacteria. In this review, multiple modes of action of thanatin in killing bacteria and in vivo activity, therapeutic potential are discussed. This promising AMP requires further research for the development of novel molecules for the treatment of infections caused by drug resistant pathogens.
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Affiliation(s)
- Rachita Dash
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore;
- Department of Systems and Computational Biology, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046, India
| | - Surajit Bhattacharjya
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore;
- Correspondence:
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Bhattacharyya D, Bhunia A. Gut-Brain axis in Parkinson's disease etiology: The role of lipopolysaccharide. Chem Phys Lipids 2020; 235:105029. [PMID: 33338469 DOI: 10.1016/j.chemphyslip.2020.105029] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 12/05/2020] [Accepted: 12/10/2020] [Indexed: 12/26/2022]
Abstract
Recent studies highlight the initiation of Parkinson's disease (PD) in the gastrointestinal tract, decades before the manifestations in the central nervous system (CNS). This gut-brain axis of neurodegenerative diseases defines the critical role played by the unique microbial composition of the "second brain" formed by the enteric nervous system (ENS). Compromise in the enteric wall can result in the translocation of gut-microbiota along with their metabolites into the system that can affect the homeostatic machinery. The released metabolites can associate with protein substrates affecting several biological pathways. Among these, the bacterial endotoxin from Gram-negative bacteria, i.e., Lipopolysaccharide (LPS), has been implicated to play a definite role in progressive neurodegeneration. The molecular interaction of the lipid metabolites can have a direct neuro-modulatory effect on homeostatic protein components that can be transported to the CNS via the vagus nerve. α-synuclein (α-syn) is one such partner protein, the molecular interactions with which modulate its overall fibrillation propensity in the system. LPS interaction has been shown to affect the protein's aggregation kinetics in an alternative inflammatory pathway of PD pathogenesis. Several other lipid contents from the bacterial membranes could also be responsible for the initiation of α-syn amyloidogenesis. The present review will focus on the intermolecular interactions of α-syn with bacterial lipid components, particularly LPS, with a definite clinical manifestation in PD pathogenesis. However, deconvolution of the sequence of interaction events from the ENS to its propagation in the CNS is not easy or obvious. Nevertheless, the characterization of these lipid-mediated structures is a step towards realizing the novel targets in the pre-emptive diagnoses of PD. This comprehensive description should prompt the correlation of potential risk of amyloidogenesis upon detection of specific paradigm shifts in the microbial composition of the gut.
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Affiliation(s)
- Dipita Bhattacharyya
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700054, India
| | - Anirban Bhunia
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700054, India.
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Liu Y, Shi D, Wang J, Chen X, Zhou M, Xi X, Cheng J, Ma C, Chen T, Shaw C, Wang L. A Novel Amphibian Antimicrobial Peptide, Phylloseptin-PV1, Exhibits Effective Anti- staphylococcal Activity Without Inducing Either Hepatic or Renal Toxicity in Mice. Front Microbiol 2020; 11:565158. [PMID: 33193152 PMCID: PMC7649123 DOI: 10.3389/fmicb.2020.565158] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 10/08/2020] [Indexed: 01/26/2023] Open
Abstract
In order to part address the problem of drug-resistant pathogens, antimicrobial peptides (AMPs) have been proposed as alternatives to traditional antibiotics. Herein, a novel phylloseptin peptide, named phylloseptin-PV1 (PPV1), is described from the defensive skin secretion of the Neotropical white-lined leaf frog, Phyllomedusa vaillantii. The peptide was synthesized by solid phase peptide synthesis (SPPS) and purified by RP-HPLC, prior to assessment of its biological activities. PPV1 not only demonstrated potent antimicrobial activity against planktonic ESKAPE microorganisms and the yeast, Candida albicans, but also inhibited and eradicated Staphylococcus aureus and MRSA biofilms. The antimicrobial mechanism was shown to include permeabilization of target cell membranes. The in vivo antimicrobial activity of the peptide was then evaluated using mice. PPV1 also exhibited antiproliferative activity against the cancer cell lines, H157, MCF-7, and U251MG, but had a lower potency against the normal cell line, HMEC-1. Although, the peptide possessed a moderate hemolytic action on mammalian red blood cells in vitro, it did not induce significant hepatic or renal toxicity in injected infected mice. These studies have thus found PPV1 to be a potent phylloseptin group AMP, which can effectively inhibit staphylococci, both in vitro and in vivo, without eliciting toxicity. These data thus provide support for further evaluation of PPV1 as a novel antimicrobial agent with therapeutic potential.
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Affiliation(s)
- Yue Liu
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China.,Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Daning Shi
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom.,School of Government, Peking University, Beijing, China
| | - Jin Wang
- Department of Chinese Medicine, Pizhou People's Hospital, Pizhou, China
| | - Xiaoling Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Mei Zhou
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Xinping Xi
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Jianming Cheng
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Chengbang Ma
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Tianbao Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Chris Shaw
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Lei Wang
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
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Chen C, Chen J, Yu Q, Zhang J, Niu X, Hao L, Yang L, Zhao Y. Effects of salts on the self-assembly behavior and antibacterial activity of a surfactant-like peptide. SOFT MATTER 2020; 16:9758-9768. [PMID: 33000840 DOI: 10.1039/d0sm01519a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Self-assembling peptides have become one of the most promising antibacterial agents due to their superior properties, such as simple molecular composition, favorable assembly structures, and rich designability. For maximum application in vivo, their activities in the presence of salts are desirable, however, the potent correlation between peptide nanostructures, antibacterial activity, and salt resistance behavior remains poorly explored. Previously, we have demonstrated that the potent antibacterial activity of a designed surfactant-like peptide Ac-A9K-NH2 benefited from its high self-assembly ability and appropriate size of its self-assembled nanostructures. In this study, we investigated the effect of salts on its self-assembly behavior and antibacterial activity. The results indicated that the flexible and long nanofibrils formed by Ac-A9K-NH2 in the presence of CaCl2 were adverse to its membrane insertion, leading to the reduction of antibacterial activity. Comparatively, Ac-A9K-NH2 maintained its potent antibacterial activity in the presence of NaCl due to its suitable shape and size of nanostructures. The newly formed nanofibers and nanorods facilitated the penetration of peptides into the bacterial membrane, forming nanopores and eventually leading to the lysis of bacteria. The high antibacterial activity and NaCl tolerance of Ac-A9K-NH2 make it a promising antibacterial agent at elevated salt concentrations.
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Affiliation(s)
- Cuixia Chen
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao Economic Development Zone, Qingdao 266555, China.
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Chen C, Li G, Cui X, Chen J, Yu Q, Zong C, Zhao Y, Xu M, Zhou S, Xu H. Mechanistic Investigation of a Self-Assembling Peptide against Escherichia coli. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9800-9809. [PMID: 32787117 DOI: 10.1021/acs.langmuir.0c01311] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Because of their distinctive mode of action in targeting bacterial cell membranes, antimicrobial peptides (AMPs) are increasingly regarded as a potential candidate for the development of novel antibiotics to combat the wide spread of bacterial resistance. To date, understanding of the exact molecular process by which AMPs act on the real bacterial envelope remains challenging. Simultaneously, the aggregated state of AMPs upon interaction with bacterial envelopes is still elusive. Previously, we have demonstrated that the potent antibacterial activity of a designed surfactant-like peptide Ac-A9K-NH2 benefited greatly from its high self-assembling ability and appropriate self-assembled morphologies and sizes. By using high-resolution atomic force microscopy, we here not only follow the variations of the Escherichia coli cell envelope in the presence of Ac-A9K-NH2 but also characterize the peptide aggregates on the bacterial surface as well as on the substrate surface. The results, together with those from fluorescence, zeta potential, circular dichroism, and scanning electron microscopy measurements, indicate that both the positively charged peptide monomers and self-assembled nanostructures can directly act on the negatively charged bacterial surface, followed by their insertion into the bacterial membrane, the formation of surface nanopores, and membrane lysis. The mechanism of Ac-A9K-NH2 against E. coli is thus consistent with the detergent-like mode of action. This work enhances our mechanistic understanding of the antibacterial behaviors of self-assembling peptides that will be valuable in exploring their biomedical applications.
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Affiliation(s)
- Cuixia Chen
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Gongrang Li
- Drilling Technology Research Institute, Sinopec Shengli Oilfield Service Corporation, Dongying 257000, China
| | - Xuejing Cui
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Jiaxi Chen
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Qizhi Yu
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Cheng Zong
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Yurong Zhao
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Minglu Xu
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Shasha Zhou
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
| | - Hai Xu
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China
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Bhattacharjya S, Straus SK. Design, Engineering and Discovery of Novel α-Helical and β-Boomerang Antimicrobial Peptides against Drug Resistant Bacteria. Int J Mol Sci 2020; 21:ijms21165773. [PMID: 32796755 PMCID: PMC7460851 DOI: 10.3390/ijms21165773] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 12/18/2022] Open
Abstract
In an era where the pipeline of new antibiotic development is drying up, the continuous rise of multi-drug resistant (MDR) and extensively drug resistant (XDR) bacteria are genuine threats to human health. Although antimicrobial peptides (AMPs) may serve as promising leads against drug resistant bacteria, only a few AMPs are in advanced clinical trials. The limitations of AMPs, namely their low in vivo activity, toxicity, and poor bioavailability, need to be addressed. Here, we review engineering of frog derived short α-helical AMPs (aurein, temporins) and lipopolysaccharide (LPS) binding designed β-boomerang AMPs for further development. The discovery of novel cell selective AMPs from the human proprotein convertase furin is also discussed.
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Affiliation(s)
- Surajit Bhattacharjya
- School of Biological Sciences, 60 Nanyang Drive, Nanyang Technological University, Singapore 637551, Singapore
- Correspondence: (S.B.); (S.K.S.)
| | - Suzana K. Straus
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
- Correspondence: (S.B.); (S.K.S.)
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12
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A Novel Antimicrobial Peptide (Kassinatuerin-3) Isolated from the Skin Secretion of the African Frog, Kassina senegalensis. BIOLOGY 2020; 9:biology9070148. [PMID: 32630734 PMCID: PMC7408539 DOI: 10.3390/biology9070148] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/21/2020] [Accepted: 06/24/2020] [Indexed: 01/05/2023]
Abstract
Amphibian skin secretions are remarkable sources of novel bioactive peptides. Among these, antimicrobial peptides have demonstrated an outstanding efficacy in killing microorganisms via a general membranolytic mechanism, which may offer the prospect of solving specific target-driven antibiotic resistance. Here, the discovery of a novel defensive peptide is described from the skin secretion of the African frog, Kassina senegalensis. Named kassinatuerin-3, it was identified through a combination of “shot-gun” cloning and MS/MS fragmentation sequencing. Subsequently, a synthetic replicate was subjected to biofunctional evaluation. The results indicated that kassinatuerin-3 possessed antimicrobial activity against Gram-positive bacteria but no effect against Gram-negative bacteria. Additionally, it was active in biofilm eradication on S. aureus and MRSA and in the antiproliferation of selected cancer cell lines. Moreover, it had a very mild hemolytic effect, which demonstrated a high therapeutic index for kassinatuerin-3. Collectively, although kassinatuerin-3 did not demonstrate remarkable bioactivities compared with other natural or synthetic antimicrobial peptides (AMPs), it offered a new insight into the design of antimicrobial derivatives.
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Bhattacharyya D, Mohite GM, Krishnamoorthy J, Gayen N, Mehra S, Navalkar A, Kotler SA, Ratha BN, Ghosh A, Kumar R, Garai K, Mandal AK, Maji SK, Bhunia A. Lipopolysaccharide from Gut Microbiota Modulates α-Synuclein Aggregation and Alters Its Biological Function. ACS Chem Neurosci 2019; 10:2229-2236. [PMID: 30855940 DOI: 10.1021/acschemneuro.8b00733] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Altered intestinal permeability has been correlated with Parkinson's pathophysiology in the enteric nervous system, before manifestations in the central nervous system (CNS). The inflammatory endotoxin or lipopolysaccharide (LPS) released by gut bacteria is known to modulate α-synuclein amyloidogenesis through the formation of intermediate nucleating species. Here, biophysical techniques in conjunction with microscopic images revealed the molecular interaction between lipopolysaccharide and α-synuclein that induce rapid nucleation events. This heteromolecular interaction stabilizes the α-helical intermediates in the α-synuclein aggregation pathway. Multitude NMR studies probed the residues involved in the LPS-binding structural motif that modulates the nucleating forms, affecting the cellular internalization and associated cytotoxicity. Collectively, our data characterizes this heteromolecular interaction associated with an alternative pathway in Parkinson's disease progression.
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Affiliation(s)
| | - Ganesh M. Mohite
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai 400076, India
| | | | - Nilanjan Gayen
- Division of Molecular Medicine, Bose Institute, Kolkata 700054, India
| | - Surabhi Mehra
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai 400076, India
| | - Ambuja Navalkar
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai 400076, India
| | - Samuel A. Kotler
- Laboratory of Chemical Physics, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Bhisma N. Ratha
- Department of Biophysics, Bose Institute, Kolkata 700054, India
| | - Anirban Ghosh
- Department of Biophysics, Bose Institute, Kolkata 700054, India
| | - Rakesh Kumar
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai 400076, India
| | - Kanchan Garai
- TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Hyderabad 500075, India
| | - Atin K. Mandal
- Division of Molecular Medicine, Bose Institute, Kolkata 700054, India
| | - Samir K. Maji
- Department of Biosciences and Bioengineering, IIT Bombay, Mumbai 400076, India
| | - Anirban Bhunia
- Department of Biophysics, Bose Institute, Kolkata 700054, India
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Potent and Broad-Spectrum Antimicrobial Activity of Analogs from the Scorpion Peptide Stigmurin. Int J Mol Sci 2019; 20:ijms20030623. [PMID: 30709056 PMCID: PMC6387013 DOI: 10.3390/ijms20030623] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 01/22/2019] [Accepted: 01/24/2019] [Indexed: 12/22/2022] Open
Abstract
Scorpion venom constitutes a rich source of biologically active compounds with high potential for therapeutic and biotechnological applications that can be used as prototypes for the design of new drugs. The aim of this study was to characterize the structural conformation, evaluate the antimicrobial activity, and gain insight into the possible action mechanism underlying it, for two new analog peptides of the scorpion peptide Stigmurin, named StigA25 and StigA31. The amino acid substitutions in the native sequence for lysine residues resulted in peptides with higher positive net charge and hydrophobicity, with an increase in the theoretical helical content. StigA25 and StigA31 showed the capacity to modify their structural conformation according to the environment, and were stable to pH and temperature variation—results similar to the native peptide. Both analog peptides demonstrated broad-spectrum antimicrobial activity in vitro, showing an effect superior to that of the native peptide, being non-hemolytic at the biologically active concentrations. Therefore, this study demonstrates the therapeutic potential of the analog peptides from Stigmurin and the promising approach of rational drug design based on scorpion venom peptide to obtain new anti-infective agents.
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15
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Identification of novel antimicrobial peptide from Asian sea bass (Lates calcarifer) by in silico and activity characterization. PLoS One 2018; 13:e0206578. [PMID: 30365554 PMCID: PMC6203393 DOI: 10.1371/journal.pone.0206578] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 10/16/2018] [Indexed: 11/29/2022] Open
Abstract
Background The global crisis of antibiotic resistance increases the demand for the new promising alternative drugs such as antimicrobial peptides (AMPs). Accordingly, we have described a new, previously unrecognized effective AMP, named dicentracin-like, from Asian sea bass and characterized its antimicrobial activity by comparison with moronecidin. Methodology/ Results Gene expression analysis demonstrated the expression of dicentracin-like peptide in tissues of the immune system such as the skin and the head kidney, which is an important endocrine and lymphoid organ. Moronecidin and dicentracin-like exhibited a higher antibacterial activity against gram-positive bacteria relative to gram-negative ones, while both peptides showed a greater binding ability to gram-negative bacteria compared to gram-positive ones. This contradiction between antibacterial activity and binding affinity may be related to the outer membrane from gram-negative bacteria. Compared with moronecidin, dicentracin-like peptide showed more potent binding ability to all gram-positive and gram-negative bacteria. In addition, dicentracin-like peptide exhibited a high antibacterial activity against the investigated microorganisms, except against Staphylococcus aureus. A direct relationship was found between the binding affinity/cationicity and the antibiofilm activity of the peptides wherein, an elevation in pH corresponded to a decrease in their antibiofilm property. Time-kill kinetics analysis against clinical Acinetobacter baumannii isolate indicated that bactericidal effect of dicentracin-like and moronecidin at inhibitory concentration (1XMIC) was observed after 4 and 6 hours, respectively, while bactericidal effect of both AMPs at concentration of 2XMIC was observed after 2 hours. Dicentracin-like peptide showed higher inhibitory activity at subinhibitory concentration (1/2XMIC), relative to moronecidin. Compared with moronecidin, dicentracin-like peptide possessed greater binding affinity to bacteria at high salt concentration, as well as at alkaline pH; In addition, dicentracin-like exhibited a higher antibiofilm activity in comparison to moronecidin even at alkaline pH. Hemolytic analysis against human RBC revealed that hemolytic activity of moronecidin was more potent than that of dicentracin-like, which is consistent with its greater non-polar face hydrophobicity. Conclusions In the present study, In Silico comparative sequence analysis and antimicrobial characterization led to identify a new, previously unrecognized antimicrobial function for named dicentracin-like peptide by comparison with moronecidin, representing a possible template for designing new effective AMPs and improving known ones.
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Mishra B, Wang X, Lushnikova T, Zhang Y, Golla RM, Narayana JL, Wang C, McGuire TR, Wang G. Antibacterial, antifungal, anticancer activities and structural bioinformatics analysis of six naturally occurring temporins. Peptides 2018; 106:9-20. [PMID: 29842923 PMCID: PMC6063800 DOI: 10.1016/j.peptides.2018.05.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 05/21/2018] [Accepted: 05/25/2018] [Indexed: 12/22/2022]
Abstract
Antimicrobial peptides are a special class of natural products with potential applications as novel therapeutics. This study focuses on six temporins (four with no activity data and two as positive controls). Using synthetic peptides, we report antibacterial, antifungal, and anticancer activities of temporins-CPa, CPb, 1Ga, 1Oc, 1Ola, and 1SPa. While temporin-1Ga and temporin-1OLa showed higher antifungal and anticancer activity, most of these peptides were active primarily against Gram-positive bacteria. Temporin-1OLa, with the highest cell selectivity index, could preferentially kill methicillin-resistant Staphylococcus aureus (MRSA), consistent with a reduced hemolysis in the presence of bacteria. Mechanistically, temporin-1OLa rapidly killed MRSA by damaging bacterial membranes. Using micelles as a membrane-mimetic model, we determined the three-dimensional structure of temporin-1OLa by NMR spectroscopy. The peptide adopted a two-domain structure where a hydrophobic patch is followed by a classic amphipathic helix covering residues P3-I12. Such a structure is responsible for anti-biofilm ability in vitro and in vivo protection of wax moths Galleria mellonella from staphylococcal infection. Finally, our bioinformatic analysis leads to a classification of temporins into six types and confers significance to this NMR structure since temporin-1OLa shares a sequence model with 62% of temporins. Collectively, our results indicate the potential of temporin-1OLa as a new anti-MRSA compound, which shows an even better anti-biofilm capability in combination with linezolid.
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Affiliation(s)
- Biswajit Mishra
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Xiuqing Wang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA; Department of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Tamara Lushnikova
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Yingxia Zhang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA; Key Laboratory of Tropical Biological Resources, Ministry of Education, College of Marine Science, Hainan University, Haikou 570228, Hainan, China
| | - Radha M Golla
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Jayaram Lakshmaiah Narayana
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Chunfeng Wang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA; The First Affiliated Hospital of Zhengzhou University, 1 Mianfang Road, Zhengzhou 450052, Henan, China
| | - Timothy R McGuire
- Department of Pharmacy Practice, University of Nebraska Medical Center, Omaha, NE 68198-6025, USA
| | - Guangshun Wang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA.
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Passarini I, Rossiter S, Malkinson J, Zloh M. In Silico Structural Evaluation of Short Cationic Antimicrobial Peptides. Pharmaceutics 2018; 10:E72. [PMID: 29933540 PMCID: PMC6160961 DOI: 10.3390/pharmaceutics10030072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 12/26/2022] Open
Abstract
Cationic peptides with antimicrobial properties are ubiquitous in nature and have been studied for many years in an attempt to design novel antibiotics. However, very few molecules are used in the clinic so far, sometimes due to their complexity but, mostly, as a consequence of the unfavorable pharmacokinetic profile associated with peptides. The aim of this work is to investigate cationic peptides in order to identify common structural features which could be useful for the design of small peptides or peptido-mimetics with improved drug-like properties and activity against Gram negative bacteria. Two sets of cationic peptides (AMPs) with known antimicrobial activity have been investigated. The first reference set comprised molecules with experimentally-known conformations available in the protein databank (PDB), and the second one was composed of short peptides active against Gram negative bacteria but with no significant structural information available. The predicted structures of the peptides from the first set were in excellent agreement with those experimentally-observed, which allowed analysis of the structural features of the second group using computationally-derived conformations. The peptide conformations, either experimentally available or predicted, were clustered in an “all vs. all” fashion and the most populated clusters were then analyzed. It was confirmed that these peptides tend to assume an amphipathic conformation regardless of the environment. It was also observed that positively-charged amino acid residues can often be found next to aromatic residues. Finally, a protocol was evaluated for the investigation of the behavior of short cationic peptides in the presence of a membrane-like environment such as dodecylphosphocholine (DPC) micelles. The results presented herein introduce a promising approach to inform the design of novel short peptides with a potential antimicrobial activity.
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Affiliation(s)
- Ilaria Passarini
- School of Life and Medical Sciences, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK.
| | - Sharon Rossiter
- School of Life and Medical Sciences, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK.
| | - John Malkinson
- UCL School of Pharmacy, University College London, 29/39 Brunswick Square, London WC1N 1AX, UK.
| | - Mire Zloh
- School of Life and Medical Sciences, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK.
- Faculty of Pharmacy, University Business Academy, Trg mladenaca 5, 21000 Novi Sad, Serbia.
- NanoPuzzle Medicines Design, Business & Technology Centre, Bessemer Drive, Stevenage SG1 2DX, UK.
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Cardoso MH, Oshiro KG, Rezende SB, Cândido ES, Franco OL. The Structure/Function Relationship in Antimicrobial Peptides: What Can we Obtain From Structural Data? THERAPEUTIC PROTEINS AND PEPTIDES 2018; 112:359-384. [DOI: 10.1016/bs.apcsb.2018.01.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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19
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Structure and Interactions of A Host Defense Antimicrobial Peptide Thanatin in Lipopolysaccharide Micelles Reveal Mechanism of Bacterial Cell Agglutination. Sci Rep 2017; 7:17795. [PMID: 29259246 PMCID: PMC5736615 DOI: 10.1038/s41598-017-18102-6] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/05/2017] [Indexed: 12/15/2022] Open
Abstract
Host defense cationic Antimicrobial Peptides (AMPs) can kill microorganisms including bacteria, viruses and fungi using various modes of action. The negatively charged bacterial membranes serve as a key target for many AMPs. Bacterial cell death by membrane permeabilization has been well perceived. A number of cationic AMPs kill bacteria by cell agglutination which is a distinctly different mode of action compared to membrane pore formation. However, mechanism of cell agglutinating AMPs is poorly understood. The outer membrane lipopolysaccharide (LPS) or the cell-wall peptidoglycans are targeted by AMPs as a key step in agglutination process. Here, we report the first atomic-resolution structure of thanatin, a cell agglutinating AMP, in complex with LPS micelle by solution NMR. The structure of thanatin in complex with LPS, revealed four stranded antiparallel β-sheet in a ‘head-tail’ dimeric topology. By contrast, thanatin in free solution assumed an antiparallel β-hairpin conformation. Dimeric structure of thanatin displayed higher hydrophobicity and cationicity with sites of LPS interactions. MD simulations and biophysical interactions analyses provided mode of LPS recognition and perturbation of LPS micelle structures. Mechanistic insights of bacterial cell agglutination obtained in this study can be utilized to develop antibiotics of alternative mode of action.
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Retro analog concept: comparative study on physico-chemical and biological properties of selected antimicrobial peptides. Amino Acids 2017; 49:1755-1771. [PMID: 28756544 PMCID: PMC5602100 DOI: 10.1007/s00726-017-2473-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 07/20/2017] [Indexed: 01/03/2023]
Abstract
Increasing drug resistance of common pathogens urgently needs discovery of new effective molecules. Antimicrobial peptides are believed to be one of the possible solutions of this problem. One of the approaches for improvement of biological properties is reversion of the sequence (retro analog concept). This research is based on investigation of antimicrobial activity against Gram-positive, Gram-negative bacteria, and fungi, hemolysis of erythrocytes, interpretation of the circular dichroism spectra, measurement of counter-ion content, and assessment of the peptide hydrophobicity and self-assembly using reversed-phase chromatography. The experiments were conducted using the following peptides: aurein 1.2, CAMEL, citropin 1.1, omiganan, pexiganan, temporin A, and their retro analogs. Among the compounds studied, only retro omiganan showed an enhanced antimicrobial and a slightly increased hemolytic activity as compared to parent molecule. Moreover, retro pexiganan exhibited high activity towards Klebsiella pneumoniae, whereas pexiganan was in general more or equally active against the rest of tested microorganisms. Furthermore, the determined activity was closely related to the peptide hydrophobicity. In general, the reduced hemolytic activity correlates with lower antimicrobial activity. The tendency to self-association and helicity fraction in SDS seems to be correlated. The normalized RP-HPLC—temperature profiles of citropin 1.1 and aurein 1.2, revealed an enhanced tendency to self-association than that of their retro analogs.
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21
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Modulation of anti-endotoxin property of Temporin L by minor amino acid substitution in identified phenylalanine zipper sequence. Biochem J 2016; 473:4045-4062. [PMID: 27609815 DOI: 10.1042/bcj20160713] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 09/07/2016] [Indexed: 11/17/2022]
Abstract
A 13-residue frog antimicrobial peptide Temporin L (TempL) possesses versatile antimicrobial activities and is considered a lead molecule for the development of new antimicrobial agents. To find out the amino acid sequences that influence the anti-microbial property of TempL, a phenylalanine zipper-like sequence was identified in it which was not reported earlier. Several alanine-substituted analogs and a scrambled peptide having the same composition of TempL were designed for evaluating the role of this motif. To investigate whether leucine residues instead of phenylalanine residues at 'a' and/or 'd' position(s) of the heptad repeat sequence could alter its antimicrobial property, several TempL analogs were synthesized after replacing these phenylalanine residues with leucine residues. Replacing phenylalanine residues with alanine residues in the phenylalanine zipper sequence significantly compromised the anti-endotoxin property of TempL. This is evident from the higher production of tumor necrosis factor-α and interleukin-6 in lipopolysaccharide (LPS)-stimulated rat bone-marrow-derived macrophage cells in the presence of its alanine-substituted analogs than TempL itself. However, replacement of these phenylalanine residues with leucine residues significantly augmented anti-endotoxin property of TempL. A single alanine-substituted TempL analog (F8A-TempL) showed significantly reduced cytotoxicity but retained the antibacterial activity of TempL, while the two single leucine-substituted analogs (F5L-TempL and F8L-TempL), although exhibiting lower cytotoxicity, were able to retain the antibacterial activity of the parent peptide. The results demonstrate how minor amino acid substitutions in the identified phenylalanine zipper sequence in TempL could yield analogs with better antibacterial and/or anti-endotoxin properties with their plausible mechanism of action.
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Mohanram H, Bhattacharjya S. 'Lollipop'-shaped helical structure of a hybrid antimicrobial peptide of temporin B-lipopolysaccharide binding motif and mapping cationic residues in antibacterial activity. Biochim Biophys Acta Gen Subj 2016; 1860:1362-72. [PMID: 27015761 DOI: 10.1016/j.bbagen.2016.03.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 03/08/2016] [Accepted: 03/20/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND Temporins are attractive templates for the development of antibiotics. However, many temporins are inactive against Gram-negative bacteria. Previously, we demonstrated conjugation of a lipopolysaccharide binding motif peptide to temporins yielded hybrid non-haemolytic AMPs that killed several Gram-negative bacteria. METHODS We carried out a systematic Ala replacement of individual cationic and polar amino acid residues of LG21, a hybrid AMP consisted of temporin B (TB) and LPS binding motif. These Ala containing analogs of LG21 were examined for antibacterial activity, cell membrane permeabilization and liposome leakage assays using optical spectroscopic methods. Atomic resolution structure of LG21 was determined in zwitterionic dodecyl phosphocholine (DPC) micelles by NMR spectroscopy. RESULTS Cationic residues in the LPS binding motif of LG21 were critical for bactericidal and membrane permeabilization. Detergent bound structure of LG21 revealed helical conformation containing extensive sidechain/sidechain packing including cation/π interactions in the LPS binding motif. The helical structure of LG21 resembled a 'lollipop' like shape that was sustained by a compacted bulky aromatic/cationic head with a comparatively thinner 'stick' at the N-terminal region. The 'head' of the structure could be localized into micelle-water interfacial region whereas the 'stick' region may be inserted into the hydrophobic core of micelle. CONCLUSIONS The LPS binding motif of LG21 played dominant roles in broad spectrum activity and the 3-D structure provided plausible mechanistic insights for permeabilization of bacterial membrane. GENERAL SIGNIFICANCE Hybrid AMPs containing LPS binding motif could be useful for the structure based development of broad spectrum antibiotics.
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Affiliation(s)
- Harini Mohanram
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Surajit Bhattacharjya
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
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23
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Ghosh A, Ratha BN, Gayen N, Mroue KH, Kar RK, Mandal AK, Bhunia A. Biophysical Characterization of Essential Phosphorylation at the Flexible C-Terminal Region of C-Raf with 14-3-3ζ Protein. PLoS One 2015; 10:e0135976. [PMID: 26295714 PMCID: PMC4546627 DOI: 10.1371/journal.pone.0135976] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 07/28/2015] [Indexed: 02/07/2023] Open
Abstract
Phosphorylation at the C-terminal flexible region of the C-Raf protein plays an important role in regulating its biological activity. Auto-phosphorylation at serine 621 (S621) in this region maintains C-Raf stability and activity. This phosphorylation mediates the interaction between C-Raf and scaffold protein 14-3-3ζ to activate the downstream MEK kinase pathway. In this study, we have defined the interaction of C-terminal peptide sequence of C-Raf with 14-3-3ζ protein and determined the possible structural adaptation of this region. Biophysical elucidation of the interaction was carried out using phosphopeptide (residue number 615–630) in the presence of 14-3-3ζ protein. Using isothermal titration calorimetry (ITC), a high binding affinity with micro-molar range was found to exist between the peptide and 14-3-3ζ protein, whereas the non-phosphorylated peptide did not show any appreciable binding affinity. Further interaction details were investigated using several biophysical techniques such as circular dichroism (CD), fluorescence, and nuclear magnetic resonance (NMR) spectroscopy, in addition to molecular modeling. This study provides the molecular basis for C-Raf C-terminal-derived phosphopeptide interaction with 14-3-3ζ protein as well as structural insights responsible for phosphorylated S621-mediated 14-3-3ζ binding at an atomic resolution.
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Affiliation(s)
- Anirban Ghosh
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700 054, India
| | - Bhisma Narayan Ratha
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700 054, India
| | - Nilanjan Gayen
- Department of Molecular Medicine, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700 054, India
| | - Kamal H. Mroue
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109–1055, United States of America
| | - Rajiv K. Kar
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700 054, India
| | - Atin K. Mandal
- Department of Molecular Medicine, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700 054, India
- * E-mail: (AKM); (AB)
| | - Anirban Bhunia
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata, 700 054, India
- * E-mail: (AKM); (AB)
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24
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Malgieri G, Avitabile C, Palmieri M, D’Andrea LD, Isernia C, Romanelli A, Fattorusso R. Structural basis of a temporin 1b analogue antimicrobial activity against Gram negative bacteria determined by CD and NMR techniques in cellular environment. ACS Chem Biol 2015; 10:965-9. [PMID: 25622128 DOI: 10.1021/cb501057d] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We here report an original approach to elucidate mechanisms of action of antimicrobial peptides and derive crucial structural requirements for the design of novel therapeutic agents. The high resolution structure of TB_KKG6A, an antimicrobial peptide designed to amplify the spectrum of action of Temporin B, bound to E. coli is here determined by means of CD and NMR methodologies. We have also defined, through STD analysis, the residues in closer proximity to the bacterial membrane.
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Affiliation(s)
- Gaetano Malgieri
- Dipartimento
di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche, Seconda Università degli studi di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Concetta Avitabile
- Diagnostica e Farmaceutiche Molecolari Scarl, Via Mezzocannone 16,80134 Napoli, Italy
| | - Maddalena Palmieri
- Dipartimento
di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche, Seconda Università degli studi di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
| | | | - Carla Isernia
- Dipartimento
di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche, Seconda Università degli studi di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Alessandra Romanelli
- Dipartimento
di Farmacia, Università di Napoli Federico II, Via Mezzocannone
16, 80134 Napoli, Italy
| | - Roberto Fattorusso
- Dipartimento
di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche, Seconda Università degli studi di Napoli, Via Vivaldi 43, 81100 Caserta, Italy
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25
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Ghosh A, Pithadia AS, Bhat J, Bera S, Midya A, Fierke CA, Ramamoorthy A, Bhunia A. Self-assembly of a nine-residue amyloid-forming peptide fragment of SARS corona virus E-protein: mechanism of self aggregation and amyloid-inhibition of hIAPP. Biochemistry 2015; 54:2249-2261. [PMID: 25785896 DOI: 10.1021/acs.biochem.5b00061] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecular self-assembly, a phenomenon widely observed in nature, has been exploited through organic molecules, proteins, DNA, and peptides to study complex biological systems. These self-assembly systems may also be used in understanding the molecular and structural biology which can inspire the design and synthesis of increasingly complex biomaterials. Specifically, use of these building blocks to investigate protein folding and misfolding has been of particular value since it can provide tremendous insights into peptide aggregation related to a variety of protein misfolding diseases, or amyloid diseases (e.g., Alzheimer's disease, Parkinson's disease, type-II diabetes). Herein, the self-assembly of TK9, a nine-residue peptide of the extra membrane C-terminal tail of the SARS corona virus envelope, and its variants were characterized through biophysical, spectroscopic, and simulated studies, and it was confirmed that the structure of these peptides influences their aggregation propensity, hence, mimicking amyloid proteins. TK9, which forms a beta-sheet rich fibril, contains a key sequence motif that may be critical for beta-sheet formation, thus making it an interesting system to study amyloid fibrillation. TK9 aggregates were further examined through simulations to evaluate the possible intra- and interpeptide interactions at the molecular level. These self-assembly peptides can also serve as amyloid inhibitors through hydrophobic and electrophilic recognition interactions. Our results show that TK9 inhibits the fibrillation of hIAPP, a 37 amino acid peptide implicated in the pathology of type-II diabetes. Thus, biophysical and NMR experimental results have revealed a molecular level understanding of peptide folding events, as well as the inhibition of amyloid-protein aggregation are reported.
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Affiliation(s)
- Anirban Ghosh
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata 700 054, India
| | - Amit S Pithadia
- Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA
| | - Jyotsna Bhat
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata 700 054, India
| | - Supriyo Bera
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata 700 054, India
| | - Anupam Midya
- School of Nanoscience and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Carol A Fierke
- Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA.,Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA.,Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ayyalusamy Ramamoorthy
- Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA.,Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA
| | - Anirban Bhunia
- Department of Biophysics, Bose Institute, P-1/12 CIT Scheme VII (M), Kolkata 700 054, India.,Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA.,Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109-1055, USA
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26
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Mohanram H, Bhattacharjya S. Cysteine deleted protegrin-1 (CDP-1): anti-bacterial activity, outer-membrane disruption and selectivity. Biochim Biophys Acta Gen Subj 2014; 1840:3006-16. [PMID: 24997421 DOI: 10.1016/j.bbagen.2014.06.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Revised: 06/14/2014] [Accepted: 06/27/2014] [Indexed: 12/26/2022]
Abstract
BACKGROUND Protegin-1 (PG-1: RGGRLCYCRRRFCVCVGR-amide) assumes a rigid β-hairpin like structure that is stabilized by two disulfide bridges between Cys6-Cys15 and Cys8-Cys13. Previous studies, employing linear analogs of PG-1, with Cys to Ala mutations or modified Cys, have demonstrated that the disulfide bridges are critical for the broad spectrum and salt resistant antimicrobial activity of PG-1. METHODS In order to understand structural and functional roles of disulfide bonds in protegrins, we have synthesized a Cys deleted variant of PG-1 or CDP-1, RGGRLYRRRFVVGR-amide, and two of its analogs, RR11, RLYRRRFVVGR-amide, and LR10, LYRRRFVVGR-amide, containing deletion of residues at the N-terminus. These peptides have been characterized for bactericidal activity and mode of action in lipopolysaccharide (LPS) using optical spectroscopy, ITC and NMR. RESULTS Antibacterial activity, against Gram-negative and Gram-positive strains, of the three peptides follows the order: CDP-1>RR11>LR10. LR10 displays only limited activity toward Gram-negative strains. CDP-1 demonstrates efficient membrane permeabilization and high-affinity interactions with LPS. CDP-1 and RR11 both assume β-hairpin like compact structures in complex with LPS, whereas LR10 adopts an extended conformation in LPS. In zwitterionic DPC micelles CDP-1 and the truncated analog peptides do not adopt folded conformations. MAJOR CONCLUSIONS Despite the absence of stabilizing disulfide bridges CDP-1 shows broad-spectrum antibacterial activity and assumes β-hairpin like structure in complex with LPS. The β-hairpin structure may be essential for outer membrane permeabilization and cell killing.
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Affiliation(s)
- Harini Mohanram
- School of Biological Sciences, Structural Biology and Biochemistry, Nanyang Technological University, 637551, Singapore
| | - Surajit Bhattacharjya
- School of Biological Sciences, Structural Biology and Biochemistry, Nanyang Technological University, 637551, Singapore.
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27
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Di Grazia A, Luca V, Segev-Zarko LAT, Shai Y, Mangoni ML. Temporins A and B stimulate migration of HaCaT keratinocytes and kill intracellular Staphylococcus aureus. Antimicrob Agents Chemother 2014; 58:2520-7. [PMID: 24514087 PMCID: PMC3993219 DOI: 10.1128/aac.02801-13] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 01/31/2014] [Indexed: 12/16/2022] Open
Abstract
The growing number of microbial pathogens resistant to available antibiotics is a serious threat to human life. Among them is the bacterium Staphylococcus aureus, which colonizes keratinocytes, the most abundant cell type in the epidermis. Its intracellular accumulation complicates treatments against resulting infections, mainly due to the limited diffusion of conventional drugs into the cells. Temporins A (Ta) and B (Tb) are short frog skin antimicrobial peptides (AMPs). Despite extensive studies regarding their antimicrobial activity, very little is known about their activity on infected cells or involvement in various immunomodulatory functions. Here we show that Tb kills both ATCC-derived and multidrug-resistant clinical isolates of S. aureus within infected HaCaT keratinocytes (80% and 40% bacterial mortality, respectively) at a nontoxic concentration, i.e., 16 μM, whereas a weaker effect is displayed by Ta. Furthermore, the peptides prevent killing of keratinocytes by the invading bacteria. Further studies revealed that both temporins promote wound healing in a monolayer of HaCaT cells, with front speed migrations of 19 μm/h and 12 μm/h for Ta and Tb, respectively. Migration is inhibited by mitomycin C and involves the epidermal growth factor receptor (EGFR) signaling pathway. Finally, confocal fluorescence microscopy indicated that the peptides diffuse into the cells. By combining antibacterial and wound-healing activities, Ta and Tb may act as multifunctional mediators of innate immunity in humans. Particularly, their nonendogenous origin may reduce microbial resistance to them as well as the risk of autoimmune diseases in mammals.
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Affiliation(s)
- Antonio Di Grazia
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche “A. Rossi Fanelli,” Sapienza Università di Roma, Rome, Italy
| | - Vincenzo Luca
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche “A. Rossi Fanelli,” Sapienza Università di Roma, Rome, Italy
| | | | - Yechiel Shai
- The Weizmann Institute of Science, Rehovot, Israel
| | - Maria Luisa Mangoni
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche “A. Rossi Fanelli,” Sapienza Università di Roma, Rome, Italy
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28
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Resurrecting inactive antimicrobial peptides from the lipopolysaccharide trap. Antimicrob Agents Chemother 2014; 58:1987-96. [PMID: 24419338 DOI: 10.1128/aac.02321-13] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Host defense antimicrobial peptides (AMPs) are a promising source of antibiotics for the treatment of multiple-drug-resistant pathogens. Lipopolysaccharide (LPS), the major component of the outer leaflet of the outer membrane of Gram-negative bacteria, functions as a permeability barrier against a variety of molecules, including AMPs. Further, LPS or endotoxin is the causative agent of sepsis killing 100,000 people per year in the United States alone. LPS can restrict the activity of AMPs inducing aggregations at the outer membrane, as observed for frog AMPs, temporins, and also in model AMPs. Aggregated AMPs, "trapped" by the outer membrane, are unable to traverse the cell wall, causing their inactivation. In this work, we show that these inactive AMPs can overcome LPS-induced aggregations while conjugated with a short LPS binding β-boomerang peptide motif and become highly bactericidal. The generated hybrid peptides exhibit activity against Gram-negative and Gram-positive bacteria in high-salt conditions and detoxify endotoxin. Structural and biophysical studies establish the mechanism of action of these peptides in LPS outer membrane. Most importantly, this study provides a new concept for the development of a potent broad-spectrum antibiotic with efficient outer membrane disruption as the mode of action.
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