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Carrillo JFC, Boaretto AG, Santana DJ, Silva DB. Skin secretions of Leptodactylidae (Anura) and their potential applications. J Venom Anim Toxins Incl Trop Dis 2024; 30:e20230042. [PMID: 38374940 PMCID: PMC10876013 DOI: 10.1590/1678-9199-jvatitd-2023-0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 12/04/2023] [Indexed: 02/21/2024] Open
Abstract
The skin of anuran species is a protective barrier against predators and pathogens, showing also chemical defense by substances that represent a potential source for bioactive substances. This review describes the current chemical and biological knowledge from the skin secretions of Leptodactylidae species, one of the most diverse neotropical frog families. These skin secretions reveal a variety of substances such as amines (12), neuropeptides (16), and antimicrobial peptides (72). The amines include histamine and its methylated derivatives, tryptamine derivatives and quaternary amines. The peptides of Leptodactylidae species show molecular weight up to 3364 Da and ocellatins are the most reported. The peptides exhibit commonly glycine (G) or glycine-valine (GV) as C-terminal amino acids, and the most common N-terminal amino acids are glutamic acid (E), lysine (K), and valine (V). The substances from Leptodactylidae species have been evaluated against pathogenic microorganisms, particularly Escherichia coli and Staphylococcus aureus, and the most active peptides showed MIC of 1-15 µM. Furthermore, some compounds showed also pharmacological properties such as immunomodulation, treatment of degenerative diseases, anticancer, and antioxidant. Currently, only 9% of the species in this family have been properly studied, highlighting a large number of unstudied species such as an entire subfamily (Paratelmatobiinae). The ecological context, functions, and evolution of peptides and amines in this family are poorly understood and represent a large field for further exploration.
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Affiliation(s)
- Juan F. C. Carrillo
- Program in Ecology and Conservation, Institute of Biosciences,
Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil
- Laboratory of Systematics and Biogeography of Amphibians and
Reptiles (Mapinguari), Institute of Biosciences, Federal University of Mato Grosso
do Sul, Campo Grande, MS, Brazil
- Laboratory of Natural Products and Mass Spectrometry (LaPNEM),
Faculty of Pharmaceutical Sciences, Food and Nutrition (FACFAN), Federal University
of Mato Grosso do Sul, Campo Grande, MS, Brazil
| | - Amanda Galdi Boaretto
- Program in Ecology and Conservation, Institute of Biosciences,
Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil
- Laboratory of Natural Products and Mass Spectrometry (LaPNEM),
Faculty of Pharmaceutical Sciences, Food and Nutrition (FACFAN), Federal University
of Mato Grosso do Sul, Campo Grande, MS, Brazil
| | - Diego J. Santana
- Program in Ecology and Conservation, Institute of Biosciences,
Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil
- Laboratory of Systematics and Biogeography of Amphibians and
Reptiles (Mapinguari), Institute of Biosciences, Federal University of Mato Grosso
do Sul, Campo Grande, MS, Brazil
| | - Denise Brentan Silva
- Program in Ecology and Conservation, Institute of Biosciences,
Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil
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2
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Conlon JM, Guilhaudis L, Attoub S, Coquet L, Leprince J, Jouenne T, Mechkarska M. Purification, conformational analysis and cytotoxic activities of host-defense peptides from the Tungara frog Engystomops pustulosus (Leptodactylidae; Leiuperinae). Amino Acids 2023; 55:1349-1359. [PMID: 37548712 PMCID: PMC10689532 DOI: 10.1007/s00726-023-03312-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
The amphibian family Leptodactylidae is divided into three sub-families: Leiuperinae, Leptodactylinae, and Paratelmatobiinae. Host-defense peptides (HDPs) present in the skins of frogs belonging to the Leptodactylinae have been studied extensively, but information is limited regarding peptides from Leiuperinae species. Peptidomic analysis of norepinephrine-stimulated skin secretions from the Tungara frog Engystomops pustulosus (Leiuperinae) collected in Trinidad led to the isolation and structural characterization of previously undescribed pustulosin-1 (FWKADVKEIG KKLAAKLAEELAKKLGEQ), [Q28E] pustulosin-1 (pustulosin-2), and pustulosin-3 (DWKETAKELLKKIGAKVAQVISDKLNPAPQ). The primary structures of these peptides do not resemble those of previously described frog skin HDPs. In addition, the secretions contained tigerinin-1EP (GCKTYLIEPPVCT) with structural similarity to the tigerinins previously identified in skin secretions from frogs from the family Dicroglossidae. Pustulosin-1 and -3 adopted extended α-helical conformations in 25% trifluoroethanol-water and in the presence of cell membrane models (sodium dodecylsulfate and dodecylphosphocholine micelles). Pustulosin-1 and -3 displayed cytotoxic activity against a range of human tumor-derived cell lines (A549, MDA-MB-231, and HT29), but their therapeutic potential for development into anti-cancer agents is limited by their comparable cytotoxic activity against non-neoplastic human umbilical vein endothelial cells. The peptides also displayed weak antimicrobial activity against Escherichia coli (MIC = 125 µM) but were inactive against Staphylococcus aureus. Tigerinin-1EP was inactive against both the tumor-derived cells and bacteria.
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Affiliation(s)
- J Michael Conlon
- Diabetes Research Centre, School of Biomedical Sciences, Ulster University, Coleraine, BT52 1SA, Northern Ireland, UK.
| | - Laure Guilhaudis
- Laboratoire COBRA (UMR 6014 & FR 3038), INSA de Rouen, CNRS, Université Rouen Normandie, 76000, Rouen, France
| | - Samir Attoub
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, 17666, Al Ain, United Arab Emirates
| | - Laurent Coquet
- CNRS UAR2026, HeRacLeS-PISSARO PBS UMR 6270, Université Rouen Normandie, 76000, Rouen, France
| | - Jérôme Leprince
- CNRS UAR2026, HeRacLeS-PISSARO PBS UMR 6270, Université Rouen Normandie, 76000, Rouen, France
- INSERM, Normandie Université, NorDiC UMR 1239, HeRacLeS, US 51, PRIMACEN, Université Rouen Normandie, 76000, Rouen, France
| | - Thierry Jouenne
- CNRS UAR2026, HeRacLeS-PISSARO PBS UMR 6270, Université Rouen Normandie, 76000, Rouen, France
| | - Milena Mechkarska
- Department of Life Sciences, Faculty of Science and Technology, The University of The West Indies, St. Augustine Campus, St. Augustine, Trinidad and Tobago
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Conlon JM, Hunter L, Attoub S, Casciaro B, Mechkarska M, Abdel-Wahab YHA. Antimicrobial, cytotoxic, and insulin-releasing activities of the amphibian host-defense peptide ocellatin-3N and its L-lysine-substituted analogs. J Pept Sci 2023; 29:e3463. [PMID: 36426386 DOI: 10.1002/psc.3463] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/12/2022] [Accepted: 11/22/2022] [Indexed: 11/26/2022]
Abstract
The host-defense peptide ocellatin-3N (GIFDVLKNLAKGVITSLAS.NH2 ), first isolated from the Caribbean frog Leptodactylus nesiotus, inhibited growth of clinically relevant Gram-positive and Gram-negative bacteria as well as a strain of the major emerging yeast pathogen Candida parapsilosis. Increasing cationicity while maintaining amphipathicity by the substitution Asp4 →Lys increased potency against the microorganisms by between 4- and 16-fold (MIC ≤3 μM) compared with the naturally occurring peptide. The substitution Ala18 →Lys and the double substitution Asp4 →Lys and Ala18 →Lys had less effects on potency. The [D4K] analog also showed 2.5- to 4-fold greater cytotoxic potency against non-small-cell lung adenocarcinoma A549 cells, breast adenocarcinoma MDA-MB-231 cells, and colorectal adenocarcinoma HT-29 cells (LC50 values in the range of 12-20 μM) compared with ocellatin-3N but was less hemolytic to mouse erythrocytes. However, the peptide showed no selectivity for tumor-derived cells [LC50 = 20 μM for human umbilical vein endothelial cells (HUVECs)]. Ocellatin-3N and [D4K]ocellatin-3N stimulated the release of insulin from BRIN-BD11 clonal β-cells at concentrations ≥1 nM, and [A18K]ocellatin-3N, at concentrations ≥0.1 nM. No peptide stimulated the release of lactate dehydrogenase at concentrations up to 3 μM, indicating that plasma membrane integrity had been preserved. The three peptides produced an increase in intracellular [Ca2+ ] in BRIN-BD11 cells when incubated at a concentration of 1 μM. In view of its high insulinotropic potency and relatively low hemolytic activity, the [A18K] ocellatin analog may represent a template for the design of agents with therapeutic potential for the treatment of patients with type 2 diabetes.
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Affiliation(s)
- J Michael Conlon
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Coleraine, UK
| | - Lauren Hunter
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Coleraine, UK
| | - Samir Attoub
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Bruno Casciaro
- Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Milena Mechkarska
- Department of Life Sciences, The University of the West Indies, St Augustine, Trinidad and Tobago
| | - Yasser H A Abdel-Wahab
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Coleraine, UK
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4
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Moreira Brito JC, Carvalho LR, Neves de Souza A, Carneiro G, Magalhães PP, Farias LM, Guimarães NR, Verly RM, Resende JM, Elena de Lima M. PEGylation of the antimicrobial peptide LyeTx I-b maintains structure-related biological properties and improves selectivity. Front Mol Biosci 2022; 9:1001508. [PMID: 36310605 PMCID: PMC9611540 DOI: 10.3389/fmolb.2022.1001508] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 09/20/2022] [Indexed: 07/31/2023] Open
Abstract
The biological activity of antimicrobial peptides and proteins is closely related to their structural aspects and is sensitive to certain post-translational modifications such as glycosylation, lipidation and PEGylation. However, PEGylation of protein and peptide drugs has expanded in recent years due to the reduction of their toxicity. Due to their size, the PEGylation process can either preserve or compromise the overall structure of these biopolymers and their biological properties. The antimicrobial peptide LyeTx I-bcys was synthesized by Fmoc strategy and coupled to polyethylene glycol 2.0 kDa. The conjugates were purified by HPLC and characterized by MALDI-ToF-MS analysis. Microbiological assays with LyeTx I-bcys and LyeTx I-bPEG were performed against Staphylococcus aureus (ATCC 33591) and Escherichia coli (ATCC 25922) in liquid medium. MIC values of 2.0 and 1.0 µM for LyeTx I-bcys and 8.0 and 4.0 µM for LyeTx I-bPEG were observed against S. aureus and E. coli, respectively. PEGylation of LyeTx I-bcys (LyeTx I-bPEG) decreased the cytotoxicity determined by MTT method for VERO cells compared to the non-PEGylated peptide. In addition, structural and biophysical studies were performed to evaluate the effects of PEGylation on the nature of peptide-membrane interactions. Surface Plasmon Resonance experiments showed that LyeTx I-b binds to anionic membranes with an association constant twice higher than the PEGylated form. The three-dimensional NMR structures of LyeTx I-bcys and LyeTx I-bPEG were determined and compared with the LyeTx I-b structure, and the hydrodynamic diameter and zeta potential of POPC:POPG vesicles were similar upon the addition of both peptides. The mPEG-MAL conjugation of LyeTx I-bcys gave epimers, and it, together with LyeTx I-bPEG, showed clear α-helical profiles. While LyeTx I-bcys showed no significant change in amphipathicity compared to LyeTx I-b, LyeTx I-bPEG was found to have a slightly less clear separation between hydrophilic and hydrophobic faces. However, the similar conformational freedom of LyeTx I-b and LyeTx I-bPEG suggests that PEGylation does not cause significant structural changes. Overall, our structural and biophysical studies indicate that the PEGylation does not alter the mode of peptide interaction and maintains antimicrobial activity while minimizing tissue toxicity, which confirmed previous results obtained in vivo. Interestingly, significantly improved proteolytic resistance to trypsin and proteinase K was observed after PEGylation.
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Affiliation(s)
| | - Lucas Raposo Carvalho
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Amanda Neves de Souza
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brazil
| | - Guilherme Carneiro
- Departamento de Farmácia, Faculdade de Ciências Biológicas e da Saúde, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brazil
| | - Paula Prazeres Magalhães
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Luiz Macêdo Farias
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Natália Rocha Guimarães
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Rodrigo Moreira Verly
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brazil
| | - Jarbas Magalhães Resende
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Maria Elena de Lima
- Programa de Pós-graduação em Medicina e Biomedicina da Santa Casa de Belo Horizonte, Belo Horizonte, MG, Brazil
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Sekar PC, Srinivasan E, Chandrasekhar G, Paul DM, Sanjay G, Surya S, Kumar NSAR, Rajasekaran R. Probing the competitive inhibitor efficacy of frog-skin alpha helical AMPs identified against ACE2 binding to SARS-CoV-2 S1 spike protein as therapeutic scaffold to prevent COVID-19. J Mol Model 2022; 28:128. [PMID: 35461388 PMCID: PMC9034900 DOI: 10.1007/s00894-022-05117-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/06/2022] [Indexed: 12/19/2022]
Abstract
In COVID-19 infection, the SARS-CoV-2 spike protein S1 interacts to the ACE2 receptor of human host, instigating the viral infection. To examine the competitive inhibitor efficacy of broad spectrum alpha helical AMPs extracted from frog skin, a comparative study of intermolecular interactions between viral S1 and AMPs was performed relative to S1-ACE2p interactions. The ACE2 binding region with S1 was extracted as ACE2p from the complex for ease of computation. Surprisingly, the Spike-Dermaseptin-S9 complex had more intermolecular interactions than the other peptide complexes and importantly, the S1-ACE2p complex. We observed how atomic displacements in docked complexes impacted structural integrity of a receptor-binding domain in S1 through conformational sampling analysis. Notably, this geometry-based sampling approach confers the robust interactions that endure in S1-Dermaseptin-S9 complex, demonstrating its conformational transition. Additionally, QM calculations revealed that the global hardness to resist chemical perturbations was found more in Dermaseptin-S9 compared to ACE2p. Moreover, the conventional MD through PCA and the torsional angle analyses indicated that Dermaseptin-S9 altered the conformations of S1 considerably. Our analysis further revealed the high structural stability of S1-Dermaseptin-S9 complex and particularly, the trajectory analysis of the secondary structural elements established the alpha helical conformations to be retained in S1-Dermaseptin-S9 complex, as substantiated by SMD results. In conclusion, the functional dynamics proved to be significant for viral Spike S1 and Dermaseptin-S9 peptide when compared to ACE2p complex. Hence, Dermaseptin-S9 peptide inhibitor could be a strong candidate for therapeutic scaffold to prevent infection of SARS-CoV-2.
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Affiliation(s)
- P Chandra Sekar
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
| | - E Srinivasan
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
- Department of Bioinformatics, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences (Deemed to Be University), Chennai, Tamil Nadu, India
| | - G Chandrasekhar
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
| | - D Meshach Paul
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
| | - G Sanjay
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
| | - S Surya
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
| | - N S Arun Raj Kumar
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India
| | - R Rajasekaran
- Quantitative Biology Lab, Department of Biotechnology, School of Bio Sciences and Technology, VIT (Deemed to Be University), Vellore, Tamil Nadu, India.
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de Assis DRR, Pimentel PMDO, Dos Reis PVM, Rabelo RAN, Vitor RWA, Cordeiro MDN, Felicori LF, Olórtegui CDC, Resende JM, Teixeira MM, Borges MH, de Lima ME, Pimenta AMDC, Machado FS. Tityus serrulatus (Scorpion): From the Crude Venom to the Construction of Synthetic Peptides and Their Possible Therapeutic Application Against Toxoplasma gondii Infection. Front Cell Infect Microbiol 2021; 11:706618. [PMID: 34354963 PMCID: PMC8329421 DOI: 10.3389/fcimb.2021.706618] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/02/2021] [Indexed: 11/22/2022] Open
Abstract
Toxoplasmosis, caused by Toxoplasma gondii, is a major public concern owing to its neurotropic nature and high morbidity and mortality rates in immunocompromised patients and newborns. Current treatment for this disease is inefficient and produces side effects. Inflammatory mediators produced during T. gondii infection (e.g., cytokines and nitric oxide) are crucial in controlling parasite replication. In this context, Tityus serrulatus venom (TsV) induces the production of inflammatory mediators by immune cells. Thus, this study aimed to isolate and identify the components of TsV with potential anti-T. gondii activity. TsV was extracted from scorpions and lyophilized or loaded onto a column to obtain its fractions. TsV subfractions were obtained using chromatography, and its amino acid sequence was identified and applied to peptide design using bioinformatics tools. The C57BL/6 mice and their harvested macrophages were used to test the anti-Toxoplasma activity of TsV components and peptides. TsV and its fraction F6 attenuated the replication of tachyzoites in macrophages and induced nitric oxide and cytokine (IL-12, TNF, and IL-6) production by infected cells, without host cell toxicity. Moreover, Su6-B toxin, a subfraction of F6, demonstrated anti-T. gondii activity. The partially elucidated and characterized amino acid sequence of Sub6-B demonstrated 93% similarity with T. serrulatus 2 toxin (Ts2). Ts2 mimetic peptides (“Pep1,” “Pep2a,” and “Pep2b”) were designed and synthesized. Pep1 and Pep2a, but not Pep2b, reduced the replication of tachyzoites in macrophages. In vivo, treatment of T. gondii-infected mice with Pep1, Pep2a, or Pep2b decreased the number of cerebral cysts and did not induce hepatotoxicity in the animals. Taken together, our data show promising immunomodulatory and antiparasitic activity of TsV that could be explored and applied in future therapies for treating infectious parasitic diseases such as toxoplasmosis.
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Affiliation(s)
- Diego Rodney Rodrigues de Assis
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Pablo Victor Mendes Dos Reis
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Rayane Aparecida Nonato Rabelo
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Ricardo Wagner Almeida Vitor
- Department of Parasitology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Liza Figueiredo Felicori
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Carlos Delfin Chávez Olórtegui
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Jarbas Magalhães Resende
- Department of Chemistry, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Mauro Martins Teixeira
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Maria Elena de Lima
- Faculdade Santa Casa de Belo Horizonte: Programa de Pós Graduação em Medicina-Biomedicina, Belo Horizonte, Brazil
| | - Adriano Monteiro de Castro Pimenta
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Fabiana Simão Machado
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.,Program in Health Sciences: Infectious Diseases and Tropical Medicine, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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7
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Muñoz-López J, Oliveira JCL, Michel DAGR, Ferreira CS, Neto FG, Salnikov ES, Verly RM, Bechinger B, Resende JM. Membrane interactions of Ocellatins. Where do antimicrobial gaps stem from? Amino Acids 2021; 53:1241-1256. [PMID: 34251525 DOI: 10.1007/s00726-021-03029-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 06/25/2021] [Indexed: 10/20/2022]
Abstract
The antimicrobial peptides Ocellatin-LB1, -LB2 and -F1, isolated from frogs, are identical from residue 1 to 22, which correspond to the -LB1 sequence, whereas -LB2 carries an extra N and -F1 additional NKL residues at their C-termini. Despite the similar sequences, previous investigations showed different spectra of activities and biophysical investigations indicated a direct correlation between both membrane-disruptive properties and activities, i.e., ocellatin-F1 > ocellatin-LB1 > ocellatin-LB2. This study presents experimental evidence as well as results from theoretical studies that contribute to a deeper understanding on how these peptides exert their antimicrobial activities and how small differences in the amino acid composition and their secondary structure can be correlated to these activity gaps. Solid-state NMR experiments allied to the simulation of anisotropic NMR parameters allowed the determination of the membrane topologies of these ocellatins. Interestingly, the extra Asn residue at the Ocellatin-LB2 C-terminus results in increased topological flexibility, which is mainly related to wobbling of the helix main axis as noticed by molecular dynamics simulations. Binding kinetics and thermodynamics of the interactions have also been assessed by Surface Plasmon Resonance and Isothermal Titration Calorimetry. Therefore, these investigations allowed to understand in atomic detail the relationships between peptide structure and membrane topology, which are in tune within the series -F1 > > -LB1 ≥ -LB2, as well as how peptide dynamics can affect membrane topology, insertion and binding.
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Affiliation(s)
- José Muñoz-López
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, P.O. Box 486, Belo Horizonte, MG, 31270-901, Brazil.,UMR7177, Institut de Chimie, Université de Strasbourg/CNRS, 4, rue Blaise Pascal , 67000, Strasbourg, France
| | - Jade C L Oliveira
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, P.O. Box 486, Belo Horizonte, MG, 31270-901, Brazil
| | - Daniel A G R Michel
- Departamento de Química, Universidade Federal Dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, 39100-000, Brazil
| | - Carolina S Ferreira
- Departamento de Química, Universidade Federal Dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, 39100-000, Brazil
| | - Francisco Gomes Neto
- Laboratório de Toxinologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, 21040-900, Brazil
| | - Evgeniy S Salnikov
- UMR7177, Institut de Chimie, Université de Strasbourg/CNRS, 4, rue Blaise Pascal , 67000, Strasbourg, France
| | - Rodrigo M Verly
- Departamento de Química, Universidade Federal Dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, 39100-000, Brazil
| | - Burkhard Bechinger
- UMR7177, Institut de Chimie, Université de Strasbourg/CNRS, 4, rue Blaise Pascal , 67000, Strasbourg, France.,Institut Universitaire de France, 75005, Paris, France
| | - Jarbas M Resende
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, P.O. Box 486, Belo Horizonte, MG, 31270-901, Brazil.
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8
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Daniele-Silva A, Rodrigues SDCS, Dos Santos ECG, Queiroz Neto MFD, Rocha HADO, Silva-Júnior AAD, Resende JM, Araújo RM, Fernandes-Pedrosa MDF. NMR three-dimensional structure of the cationic peptide Stigmurin from Tityus stigmurus scorpion venom: In vitro antioxidant and in vivo antibacterial and healing activity. Peptides 2021; 137:170478. [PMID: 33359395 DOI: 10.1016/j.peptides.2020.170478] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 01/05/2023]
Abstract
Infectious diseases and the rapid development of pathogens resistant to conventional drugs are a serious global public health problem, which motivates the search for new pharmacological agents. In this context, cationic peptides without disulfide bridges from different species of scorpion venom have been the target of scientific studies due to their multifunctional activities. Stigmurin is a linear peptide composed of 17 amino acid residues (Phe-Phe-Ser-Leu-Ile-Pro-Ser-Leu-Val-Gly-Gly-Leu-Ile-Ser-Ala-Phe-Lys-NH2), which is present in the venom gland of the scorpion Tityus stigmurus. Here we present investigations of the in vitro antioxidant action of Stigmurin together with the in vivo antibacterial and healing activity of this peptide in a wound infection model induced by Staphylococcus aureus. In addition, we have reports for the first time of the three-dimensional structure determined by NMR spectroscopy of a peptide without disulfide bridges present in scorpion venom from the Tityus genus. Stigmurin showed hydroxyl radical scavenging above 70 % at 10 μM and antibiotic action in the skin wound, reducing the number of viable microorganisms by 67.2 % on the 7 day after infection. Stigmurin (1 μg / μL) increased the retraction rate of the lesion, with wound area reduction of 43 % on the second day after skin injury, which indicates its ability to induce tissue repair. Stigmurin in trifluoroethanol:water exhibited a random conformation at the N-terminus region (Phe1 to Pro6), with a helical structure from Ser7 to Phe16. This structural information, allied with the multifunctional activity of Stigmurin, makes it an attractive candidate for the design of novel therapeutic agents.
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Affiliation(s)
- Alessandra Daniele-Silva
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Departamento de Farmácia, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | - Suedson de Carvalho Silva Rodrigues
- Laboratório de Isolamento e Síntese de Compostos Orgânicos, Instituto de Química, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | | | - Moacir Fernandes de Queiroz Neto
- Laboratório de Biotecnologia de Polímeros Naturais, Departamento de Bioquímica, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | - Hugo Alexandre de Oliveira Rocha
- Laboratório de Biotecnologia de Polímeros Naturais, Departamento de Bioquímica, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | - Arnóbio Antônio da Silva-Júnior
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Departamento de Farmácia, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | - Jarbas Magalhães Resende
- Laboratório de Síntese e Estrutura de Peptídeos, Departamento de Química, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Renata Mendonça Araújo
- Laboratório de Isolamento e Síntese de Compostos Orgânicos, Instituto de Química, Universidade Federal do Rio Grande do Norte, Natal, Brazil
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9
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Nunes LO, Munhoz VHO, Sousa AA, de Souza KR, Santos TL, Bemquerer MP, Ferreira DEC, de Magalhães MTQ, Resende JM, Alcântara AFC, Aisenbrey C, Veloso DP, Bechinger B, Verly RM. High-resolution structural profile of hylaseptin-4: Aggregation, membrane topology and pH dependence of overall membrane binding process. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183581. [PMID: 33556358 DOI: 10.1016/j.bbamem.2021.183581] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/20/2021] [Accepted: 02/03/2021] [Indexed: 12/11/2022]
Abstract
Hylaseptin-4 (HSP-4, GIGDILKNLAKAAGKAALHAVGESL-NH2) is an antimicrobial peptide originally isolated from Hypsiboas punctatus tree frog. The peptide has been chemically synthetized for structural investigations by CD and NMR spectroscopies. CD experiments reveal the high helical content of HSP-4 in biomimetic media. Interestingly, the aggregation process seems to occur at high peptide concentrations either in aqueous solution or in presence of biomimetic membranes, indicating an increase in the propensity of the peptide for adopting a helical conformation. High-resolution NMR structures determined in presence of DPC-d38 micelles show a highly ordered α-helix from amino acid residues I2 to S24 and a smooth bend near G14. A large separation between hydrophobic and hydrophilic residues occurs up to the A16 residue, from which a shift in the amphipathicity is noticed. Oriented solid-state NMR spectroscopy show a roughly parallel orientation of the helical structure along the POPC lipid bilayer surface, with an insertion of the hydrophobic N-terminus into the bilayer core. Moreover, a noticeable pH dependence of the aggregation process in both aqueous and in biomimetic membrane environments is attributed to a single histidine residue (H19). The protonation degree of the imidazole side-chain might help in modulating the peptide-peptide or peptide-lipid interactions. Finally, molecular dynamics simulations confirm the orientation and preferential helical conformation and in addition, show that HSP-4 tends to self-aggregate in order to stabilize its active conformation in aqueous or phospholipid bilayer environments.
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Affiliation(s)
- L O Nunes
- Departamento de Química, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil
| | - V H O Munhoz
- Instituto de Ciência e Tecnologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil
| | - A A Sousa
- Departamento de Química, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil
| | - K R de Souza
- Departamento de Química, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil
| | - T L Santos
- Departamento de Química, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil
| | - M P Bemquerer
- Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, PqEB, Av. W5 Norte (final), P.O. Box 02372, Brasília, DF, Brazil
| | - D E C Ferreira
- Departamento de Química, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil; Departamento de Química, Universidade Federal de Minas Gerais, P.O. Box 486, 31270-901 Belo Horizonte, MG, Brazil
| | - Mariana T Q de Magalhães
- Departamento de Bioquímica e Imunologia, Laboratório de Biofísica de Macromoléculas Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
| | - J M Resende
- Departamento de Química, Universidade Federal de Minas Gerais, P.O. Box 486, 31270-901 Belo Horizonte, MG, Brazil
| | - A F C Alcântara
- Departamento de Química, Universidade Federal de Minas Gerais, P.O. Box 486, 31270-901 Belo Horizonte, MG, Brazil
| | - C Aisenbrey
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 67000 Strasbourg, France
| | - D P Veloso
- Departamento de Química, Universidade Federal de Minas Gerais, P.O. Box 486, 31270-901 Belo Horizonte, MG, Brazil
| | - B Bechinger
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 67000 Strasbourg, France; Institut Universitaire de France (IUF), France
| | - R M Verly
- Departamento de Química, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 39100-000 Diamantina, MG, Brazil.
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10
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Sekar PC, Paul DM, Srinivasan E, Rajasekaran R. Unravelling the molecular effect of ocellatin-1, F1, K1 and S1, the frog-skin antimicrobial peptides to enhance its therapeutics-quantum and molecular mechanical approaches. J Mol Model 2021; 27:10. [PMID: 33392722 DOI: 10.1007/s00894-020-04652-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 12/16/2020] [Indexed: 01/09/2023]
Abstract
Ocellatin AMPs (antimicrobial peptides) are considered to be promising alternative therapeutics to conventional antibiotics. Three-dimensional (3D) structures of ocellatin-F1 with 25 residues have been reported to be potent in terms of bacterial membrane permeability. To investigate the influence of similar ocellatin peptides with 25 residues pertaining to antimicrobial effect, ocellatin-1, K1 and S1 peptides were modelled with ocellatin-F1 as template. Comparative analyses between these peptides were carried out, using computational approaches. From the results of in silico toxicity profile, all peptides were found to be non-toxic with no haemolytic activity. Further sequence analysis, net charge, hydrophobicity and hydrophobic moment revealed the membrane permeable efficacy of ocellatin-1 peptide. Besides, the investigation of peptide electronic structures through density functional theory and quantum chemical (HOMO and LUMO) calculations predicted ocellatin-1 to be a suitable peptide, which can be used as a scaffold for therapeutics. Furthermore, the determination of structural contours such as RMSD, RMSF and Rg through trajectory analysis revealed that ocellatin-1 exhibited strong structural stability. In addition, the trajectory analysis of elements of secondary structure illustrated the alpha helical conformations to be retained in all peptides, except ocellatin-1. On the aforementioned grounds, ocellatin-1 was found to possess the important role of peptide penetration of the bacterial membrane. This study becomes significant, since it is the first time where the structural importance of ocellatin peptides were explored in detail and the therapeutic potential of ocellatin-1 as a peptide-based antimicrobial drug have been theoretically revealed.
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Affiliation(s)
- P Chandra Sekar
- Bioinformatics Lab, Department of Biotechnology, School of BioSciences and Technology, Vellore Institute of Technology (Deemed to be University), Vellore, Tamil Nadu, India
| | - D Meshach Paul
- Bioinformatics Lab, Department of Biotechnology, School of BioSciences and Technology, Vellore Institute of Technology (Deemed to be University), Vellore, Tamil Nadu, India
| | - E Srinivasan
- Bioinformatics Lab, Department of Biotechnology, School of BioSciences and Technology, Vellore Institute of Technology (Deemed to be University), Vellore, Tamil Nadu, India
| | - R Rajasekaran
- Bioinformatics Lab, Department of Biotechnology, School of BioSciences and Technology, Vellore Institute of Technology (Deemed to be University), Vellore, Tamil Nadu, India.
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11
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Ferraro DP, Pereyra MO, Topa PE, Faivovich J. Evolution of macroglands and defensive mechanisms in Leiuperinae (Anura: Leptodactylidae). Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlaa149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Abstract
Anurans show a wide variety of anti-predator mechanisms, and the species of the Neotropical clade Leiuperinae display several of them. Most species of Edalorhina, Physalaemus and Pleurodema show eyespots, hidden bright colours, macroglands in a inguinal/lumbar position, defensive behaviours and/or chemical defence. We conducted a histological analysis of dorsal and lumbar skin and revised the colour patterns, defensive behaviours and glandular secretions to study the diversity and evolution of anti-predator mechanisms associated with macroglands. We describe 17 characters and optimize these in a phylogenetic hypothesis of Leiuperinae. In the most recent common ancestor of Edalorhina + Engystomops + Physalaemus + Pleurodema, a particular type of serous gland (the main component of macroglands) evolved in the lumbar skin, along with the absence of the Eberth–Katschenko layer. A defensive behaviour observed in leiuperines with macroglands includes four displays (‘crouching down’ behaviour, rear elevation, body inflation and eye protection), all present in the same ancestor. The two elements associated with aposematism (hidden bright colours and eyespots) evolved independently in several species. Our results provide phylogenetic evidence for the startle-first hypothesis, which suggests that behavioural displays arise as sudden movements in camouflaged individuals to avoid predatory attacks, before the origin of bright coloration.
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Affiliation(s)
- Daiana Paola Ferraro
- División Herpetología, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’ (CONICET), Buenos Aires, Argentina
| | - Martín Oscar Pereyra
- Laboratorio de Genética Evolutiva ‘Claudio J. Bidau’, Instituto de Biología Subtropical (IBS, CONICET), Universidad Nacional de Misiones (UNaM), Posadas, Misiones, Argentina
| | - Pascual Emilio Topa
- Centro de Estudios Parasitológicos y de Vectores (CONICET), La Plata, Buenos Aires, Argentina
| | - Julián Faivovich
- División Herpetología, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’ (CONICET), Buenos Aires, Argentina
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12
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Membrane interactions of the anuran antimicrobial peptide HSP1-NH 2: Different aspects of the association to anionic and zwitterionic biomimetic systems. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183449. [PMID: 32828849 DOI: 10.1016/j.bbamem.2020.183449] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 08/08/2020] [Accepted: 08/17/2020] [Indexed: 11/21/2022]
Abstract
Studies have suggested that antimicrobial peptides act by different mechanisms, such as micellisation, self-assembly of nanostructures and pore formation on the membrane surface. This work presents an extensive investigation of the membrane interactions of the 14 amino-acid antimicrobial peptide hylaseptin P1-NH2 (HSP1-NH2), derived from the tree-frog Hyla punctata, which has stronger antifungal than antibacterial potential. Biophysical and structural analyses were performed and the correlated results were used to describe in detail the interactions of HSP1-NH2 with zwitterionic and anionic detergent micelles and phospholipid vesicles. HSP1-NH2 presents similar well-defined helical conformations in both zwitterionic and anionic micelles, although NMR spectroscopy revealed important structural differences in the peptide N-terminus. 2H exchange experiments of HSP1-NH2 indicated the insertion of the most N-terminal residues (1-3) in the DPC-d38 micelles. A higher enthalpic contribution was verified for the interaction of the peptide with anionic vesicles in comparison with zwitterionic vesicles. The pore formation ability of HSP1-NH2 (examined by dye release assays) and its effect on the size and surface charge as well as on the lipid acyl chain ordering (evaluated by Fourier-transform infrared spectroscopy) of anionic phospholipid vesicles showed membrane disruption even at low peptide-to-phospholipid ratios, and the effect increases proportionately to the peptide concentration. On the other hand, these biophysical investigations showed that a critical peptide-to-phospholipid ratio around 0.6 is essential for promoting disruption of zwitterionic membranes. In conclusion, this study demonstrates that the binding process of the antimicrobial HSP1-NH2 peptide depends on the membrane composition and peptide concentration.
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13
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van den Bergen G, Stroet M, Caron B, Poger D, Mark AE. Curved or linear? Predicting the 3-dimensional structure of α-helical antimicrobial peptides in an amphipathic environment. FEBS Lett 2019; 594:1062-1080. [PMID: 31794050 DOI: 10.1002/1873-3468.13705] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/21/2019] [Accepted: 11/23/2019] [Indexed: 12/13/2022]
Abstract
α-Helical membrane-active antimicrobial peptides (AMPs) are known to act via a range of mechanisms, including the formation of barrel-stave and toroidal pores and the micellisation of the membrane (carpet mechanism). Different mechanisms imply that the peptides adopt different 3D structures when bound at the water-membrane interface, a highly amphipathic environment. Here, an evolutionary algorithm is used to predict the 3D structure of a range of α-helical membrane-active AMPs at the water-membrane interface by optimising amphipathicity. This amphipathic structure prediction (ASP) is capable of distinguishing between curved and linear peptides solved experimentally, potentially allowing the activity and mechanism of action of different membrane-active AMPs to be predicted. The ASP algorithm is accessible via a web interface at http://atb.uq.edu.au/asp/.
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Affiliation(s)
- Glen van den Bergen
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Martin Stroet
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Bertrand Caron
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - David Poger
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Alan E Mark
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
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14
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Vincenzi M, Mercurio FA, Leone M. About TFE: Old and New Findings. Curr Protein Pept Sci 2019; 20:425-451. [PMID: 30767740 DOI: 10.2174/1389203720666190214152439] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 07/16/2018] [Accepted: 07/18/2018] [Indexed: 01/28/2023]
Abstract
The fluorinated alcohol 2,2,2-Trifluoroethanol (TFE) has been implemented for many decades now in conformational studies of proteins and peptides. In peptides, which are often disordered in aqueous solutions, TFE acts as secondary structure stabilizer and primarily induces an α -helical conformation. The exact mechanism through which TFE plays its stabilizing roles is still debated and direct and indirect routes, relying either on straight interaction between TFE and molecules or indirect pathways based on perturbation of solvation sphere, have been proposed. Another still unanswered question is the capacity of TFE to favor in peptides a bioactive or a native-like conformation rather than simply stimulate the raise of secondary structure elements that reflect only the inherent propensity of a specific amino-acid sequence. In protein studies, TFE destroys unique protein tertiary structure and often leads to the formation of non-native secondary structure elements, but, interestingly, gives some hints about early folding intermediates. In this review, we will summarize proposed mechanisms of TFE actions. We will also describe several examples, in which TFE has been successfully used to reveal structural properties of different molecular systems, including antimicrobial and aggregation-prone peptides, as well as globular folded and intrinsically disordered proteins.
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Affiliation(s)
- Marian Vincenzi
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via Mezzocannone 16, 80134 Naples, Italy
| | - Flavia A Mercurio
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via Mezzocannone 16, 80134 Naples, Italy.,Cirpeb, InterUniversity Research Centre on Bioactive Peptides, University of Naples "Federico II", Via Mezzocannone 16, 80134 Naples, Italy
| | - Marilisa Leone
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via Mezzocannone 16, 80134 Naples, Italy.,Cirpeb, InterUniversity Research Centre on Bioactive Peptides, University of Naples "Federico II", Via Mezzocannone 16, 80134 Naples, Italy
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