1
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Slezina MP, Odintsova TI. Plant Antimicrobial Peptides: Insights into Structure-Function Relationships for Practical Applications. Curr Issues Mol Biol 2023; 45:3674-3704. [PMID: 37185763 PMCID: PMC10136942 DOI: 10.3390/cimb45040239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/17/2023] [Accepted: 04/20/2023] [Indexed: 05/17/2023] Open
Abstract
Antimicrobial peptides (AMPs) are short polypeptide molecules produced by multicellular organisms that are involved in host defense and microbiome preservation. In recent years, AMPs have attracted attention as novel drug candidates. However, their successful use requires detailed knowledge of the mode of action and identification of the determinants of biological activity. In this review, we focused on structure-function relationships in the thionins, α-hairpinins, hevein-like peptides, and the unique Ib-AMP peptides isolated from Impatiens balsamina. We summarized the available data on the amino acid sequences and 3D structure of peptides, their biosynthesis, and their biological activity. Special attention was paid to the determination of residues that play a key role in the activity and the identification of the minimal active cores. We have shown that even subtle changes in amino acid sequences can affect the biological activity of AMPs, which opens up the possibility of creating molecules with improved properties, better therapeutic efficacy, and cheaper large-scale production.
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Affiliation(s)
- Marina P Slezina
- Vavilov Institute of General Genetics RAS, 119333 Moscow, Russia
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2
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Lima HVD, Dos Santos TMC, de Sousa Silva MMA, da Silva Albuquerque JV, Melo LM, de Figueirêdo Freitas VJ, Rádis-Baptista G. The Rhodamine B-encrypted vipericidin peptide, RhoB-Ctn[1-9], displays in vitro antimicrobial activity against opportunistic bacteria and yeasts. Curr Pharm Biotechnol 2021; 23:172-179. [PMID: 33749557 DOI: 10.2174/1389201022666210322123903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 01/05/2021] [Accepted: 02/09/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Crotalicidin (Ctn), a snake venom cathelicidin-related antimicrobial peptide, is a 34-residue-long linear lysine-rich vipericidin obtained from the South American rattlesnake, Crotalus durissus terrificus. Ctn contains tandem repeats of nine amino acid residues (1KRFKKFFKK9 and 16KRLKKIFKK24; consensus: 1KRhKKhFKK9, h = hydrophobic amino acid) as an integral part of its structure. OBJECTIVE The aim of this study was to evaluate the antimicrobial activity of the encrypted vipericidin nonapeptide KRFKKFFKK, designated as Ctn[1-9], and its structural analogue, rhodamine-B‒conjugated Ctn[1-9], designated as RhoB-Ctn[1-9]. METHOD The susceptibility of representative pathogenic bacteria and yeasts to antimicrobial agents was determined using the broth microdilution minimum inhibitory concentration (MIC) method. Cytotoxicity was estimated using a hemolytic assay. The accumulation of RhoB-Ctn[1-9] in microbial cells was observed by fluorescence microscopy. The antimicrobial synergism of RhoB-Ctn[1-9] with antimicrobials was evaluated using a checkerboard analysis. RESULTS RhoB-conjugated Ctn[1-9] displayed selective antimicrobial activity against infectious gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, and pathogenic species of Candida with low hemolytic effects on human erythrocytes which was not observed with unconjugated Ctn[1-9]. RhoB-Ctn[1-9] could permeate cell membranes and accumulate intracellularly in microbial cells. RhoB-Ctn[1-9] exhibits synergistic effects when used with antibiotics or antifungal agents and reduced the MICs of the peptide and antimicrobials. CONCLUSION These findings indicate the potential of crotalicidin-related short peptides as structural motifs for the diversification of biological functionalities. Further, they set the stage to investigate the molecular mechanisms by which chemically modified vipericidin repeats modulate cell fate.
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Affiliation(s)
- Hilania Valeria Doudou Lima
- Laboratory of Biochemistry and Biotechnology, Institute of Marine Science, Federal University of Ceará (UFC), Fortaleza-CE. Brazil
| | - Thales Márcio Cabral Dos Santos
- Laboratory of Physiology and Control of Reproduction, Faculty of Veterinary, State University of Ceará (UECE), Fortaleza-CE. Brazil
| | | | - João Victor da Silva Albuquerque
- Laboratory of Physiology and Control of Reproduction, Faculty of Veterinary, State University of Ceará (UECE), Fortaleza-CE. Brazil
| | - Luciana Magalhães Melo
- Laboratory of Physiology and Control of Reproduction, Faculty of Veterinary, State University of Ceará (UECE), Fortaleza-CE. Brazil
| | | | - Gandhi Rádis-Baptista
- Laboratory of Biochemistry and Biotechnology, Institute of Marine Science, Federal University of Ceará (UFC), Fortaleza-CE. Brazil
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3
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Skalska J, Andrade VM, Cena GL, Harvey PJ, Gaspar D, Mello ÉO, Henriques ST, Valle J, Gomes VM, Conceição K, Castanho MARB, Andreu D. Synthesis, Structure, and Activity of the Antifungal Plant Defensin PvD 1. J Med Chem 2020; 63:9391-9402. [PMID: 32787086 DOI: 10.1021/acs.jmedchem.0c00543] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Available treatments for invasive fungal infections have limitations, including toxicity and the emergence of resistant strains. Therefore, there is an urgent need for alternative solutions. Because of their unique mode of action and high selectivity, plant defensins (PDs) are worthy therapeutic candidates. Chemical synthesis remains a preferred method for the production of many peptide-based therapeutics. Given the relatively long sequence of PDs, as well as their complicated posttranslational modifications, the synthetic route can be considered challenging. Here, we describe a total synthesis of PvD1, the defensin from the common bean Phaseolus vulgaris. Analytical, structural, and functional characterization revealed that both natural and synthetic peptides fold into a canonical CSαβ motif stabilized by conserved disulfide bonds. Moreover, synthetic PvD1 retained the biological activity against four different Candida species and showed no toxicity in vivo. Adding the high resistance of synthetic PvD1 to proteolytic degradation, we claim that conditions are now met to consider PDs druggable biologicals.
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Affiliation(s)
- Julia Skalska
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal
| | - Vitor M Andrade
- Laboratório de Bioquı́mica de Peptı́deos, Universidade Federal de São Paulo, 12231-280 São José dos Campos, Brazil
| | - Gabrielle L Cena
- Laboratório de Bioquı́mica de Peptı́deos, Universidade Federal de São Paulo, 12231-280 São José dos Campos, Brazil
| | - Peta J Harvey
- Institute for Molecular Bioscience, The University of Queensland, 4072 Brisbane, Queensland, Australia
| | - Diana Gaspar
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal
| | - Érica O Mello
- Laboratório de Fisiologia e Bioquı́mica de Microrganismos, Centro de Biociências e Biotecnologı́a, Universidade Estadual do Norte Fluminense Darcy Ribeiro, 28013-602 Rio de Janeiro, Brazil
| | - Sónia T Henriques
- Institute for Molecular Bioscience, The University of Queensland, 4072 Brisbane, Queensland, Australia.,School of Biomedical Sciences, Institute of Health & Biomedical Innovation and Translational Research Institute, Queensland University of Technology, Brisbane, Queensland 4102, Australia
| | - Javier Valle
- Department of Experimental and Health Sciences, Barcelona Biomedical Research Park, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Valdirene M Gomes
- Laboratório de Fisiologia e Bioquı́mica de Microrganismos, Centro de Biociências e Biotecnologı́a, Universidade Estadual do Norte Fluminense Darcy Ribeiro, 28013-602 Rio de Janeiro, Brazil
| | - Katia Conceição
- Laboratório de Bioquı́mica de Peptı́deos, Universidade Federal de São Paulo, 12231-280 São José dos Campos, Brazil
| | - Miguel A R B Castanho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal
| | - David Andreu
- Department of Experimental and Health Sciences, Barcelona Biomedical Research Park, Universitat Pompeu Fabra, 08003 Barcelona, Spain
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4
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Yathursan S, Wiles S, Read H, Sarojini V. A review on anti-tuberculosis peptides: Impact of peptide structure on anti-tuberculosis activity. J Pept Sci 2019; 25:e3213. [PMID: 31515916 DOI: 10.1002/psc.3213] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 08/03/2019] [Accepted: 08/07/2019] [Indexed: 12/18/2022]
Abstract
Antibiotic resistance is a major public health problem globally. Particularly concerning amongst drug-resistant human pathogens is Mycobacterium tuberculosis that causes the deadly infectious tuberculosis (TB) disease. Significant issues associated with current treatment options for drug-resistant TB and the high rate of mortality from the disease makes the development of novel treatment options against this pathogen an urgent need. Antimicrobial peptides are part of innate immunity in all forms of life and could provide a potential solution against drug-resistant TB. This review is a critical analysis of antimicrobial peptides that are reported to be active against the M tuberculosis complex exclusively. However, activity on non-TB strains such as Mycobacterium avium and Mycobacterium intracellulare, whenever available, have been included at appropriate sections for these anti-TB peptides. Natural and synthetic antimicrobial peptides of diverse sequences, along with their chemical structures, are presented, discussed, and correlated to their observed antimycobacterial activities. Critical analyses of the structure allied to the anti-mycobacterial activity have allowed us to draw important conclusions and ideas for research and development on these promising molecules to realise their full potential. Even though the review is focussed on peptides, we have briefly summarised the structures and potency of the various small molecule drugs that are available and under development, for TB treatment.
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Affiliation(s)
- Sutharsana Yathursan
- School of Chemical Sciences, University of Auckland, Private Bag, 92019, Auckland, New Zealand
| | - Siouxsie Wiles
- Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Private Bag, 92019, Auckland, New Zealand
| | - Hannah Read
- Bioluminescent Superbugs Lab, Department of Molecular Medicine and Pathology, University of Auckland, Private Bag, 92019, Auckland, New Zealand
| | - Vijayalekshmi Sarojini
- School of Chemical Sciences, University of Auckland, Private Bag, 92019, Auckland, New Zealand.,The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, 6140, New Zealand
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5
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A structural perspective of plant antimicrobial peptides. Biochem J 2018; 475:3359-3375. [PMID: 30413680 DOI: 10.1042/bcj20180213] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 10/12/2018] [Accepted: 10/14/2018] [Indexed: 12/26/2022]
Abstract
Among the numerous strategies plants have developed to fend off enemy attack, antimicrobial peptides (AMPs) stand out as one of the most prominent defensive barriers that grant direct and durable resistance against a wide range of pests and pathogens. These small proteins are characterized by a compact structure and an overall positive charge. AMPs have an ancient origin and widespread occurrence in the plant kingdom but show an unusually high degree of variation in their amino acid sequences. Interestingly, there is a strikingly conserved topology among the plant AMP families, suggesting that the defensive properties of these peptides are not determined by their primary sequences but rather by their tridimensional structure. To explore and expand this idea, we here discuss the role of AMPs for plant defense from a structural perspective. We show how specific structural properties, such as length, charge, hydrophobicity, polar angle and conformation, are essential for plant AMPs to act as a chemical shield that hinders enemy attack. Knowledge on the topology of these peptides is facilitating the isolation, classification and even structural redesign of AMPs, thus allowing scientists to develop new peptides with multiple agronomical and pharmacological potential.
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6
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Odintsova TI, Slezina MP, Istomina EA. Plant thionins: structure, biological functions and potential use in biotechnology. Vavilovskii Zhurnal Genet Selektsii 2018. [DOI: 10.18699/vj18.409] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Antimicrobial peptides (AMPs) are important components of defense system in both plants and animals. They represent an ancient mechanism of innate immunity providing rapid first line of defense against pathogens. Plant AMPs are classified into several families: thionins, defensins, nonspecific lipid-transfer proteins, hevein- and knottin-type peptides, hairpinins and macrocyclic peptides (cyclotides). The review focuses on the thionin family. Thionins comprise a plant-specific AMP family that consists of short (~5 kDA) cysteine-rich peptides containing 6 or 8 cysteine residues with antimicrobial and toxic properties. Based on similarity in amino acid sequences and the arrangement of disulphide bonds, five structural classes of thionins are discriminated. The three-dimensional structures of a number of thionins were determined. The amphipathic thionin molecule resembles the Greek letter Г, in which the long arm is formed by two antiparallel α-helices, while the short one, by two parallel β-strands. The residues responsible for the antimicrobial activity of thionins were identified. Thionins are synthesized as precursor proteins consisting of a signal peptide, the mature peptide region and the C-terminal prodomain. Thionins protect plants from pathogenic bacteria and fungi acting directly on the membranes of microorganisms at micromolar concentrations, although their precise mode of action remains unclear. In addition to plant pathogens, thionins inhibit growth of a number of human pathogens and opportunistic microorganisms, such as Candida spp., Saccharomyces cerevisiae, Fusarium solani, Staphylococcus aureus and Escherichia coli. Thionins are toxic to different types of cells including mammalian cancer cell lines. Transgenic plants expressing thionin genes display enhanced resistance to pathogens. A wide range of biological activities makes thionins promising candidates for practical application in agriculture and medicine.
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7
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Rodríguez-Decuadro S, Barraco-Vega M, Dans PD, Pandolfi V, Benko-Iseppon AM, Cecchetto G. Antimicrobial and structural insights of a new snakin-like peptide isolated from Peltophorum dubium (Fabaceae). Amino Acids 2018; 50:1245-1259. [PMID: 29948342 DOI: 10.1007/s00726-018-2598-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/31/2018] [Indexed: 02/02/2023]
Abstract
Snakins are antimicrobial peptides (AMPs) found, so far, exclusively in plants, and known to be important in the defense against a wide range of pathogens. Like other plant AMPs, they contain several positively charged amino acids, and an even number of cysteine residues forming disulfide bridges which are considered important for their usual function. Despite its importance, studies on snakin tertiary structure and mode of action are still scarce. In this study, a new snakin-like gene was isolated from the native plant Peltophorum dubium, and its expression was verified in seedlings and adult leaves. The deduced peptide (PdSN1) shows 84% sequence identity with potato snakin-1 mature peptide, with the 12 cysteines characteristic from this peptide family at the GASA domain. The mature PdSN1 coding sequence was successfully expressed in Escherichia coli. The purified recombinant peptide inhibits the growth of important plant and human pathogens, like the economically relevant potato pathogen Streptomyces scabies and the opportunistic fungi Candida albicans and Aspergillus niger. Finally, homology and ab initio modeling techniques coupled to extensive molecular dynamics simulations were used to gain insight on the 3D structure of PdSN1, which exhibited a helix-turn-helix motif conserved in both native and recombinant peptides. We found this motif to be strongly coded in the sequence of PdSN1, as it is stable under different patterns of disulfide bonds connectivity, and even when the 12 cysteines are considered in their reduced form, explaining the previous experimental evidences.
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Affiliation(s)
- Susana Rodríguez-Decuadro
- Departamento de Biología Vegetal, Facultad de Agronomía, Universidad de la República, Garzón 780, 12900, Montevideo, Uruguay
| | - Mariana Barraco-Vega
- Departamento de Biociencias, Facultad de Química, Universidad de la República, General Flores 2124, 11800, Montevideo, Uruguay
| | - Pablo D Dans
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain.,Joint BSC-IRB Research Program in Computational Biology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Valesca Pandolfi
- Universidade Federal de Pernambuco, Centro de Biociências, Av. Prof. Moraes Rego, 1235, Recife, PE, CEP 50.670-420, Brazil
| | - Ana Maria Benko-Iseppon
- Universidade Federal de Pernambuco, Centro de Biociências, Av. Prof. Moraes Rego, 1235, Recife, PE, CEP 50.670-420, Brazil
| | - Gianna Cecchetto
- Departamento de Biociencias, Facultad de Química, Universidad de la República, General Flores 2124, 11800, Montevideo, Uruguay. .,Instituto de Química Biológica, Facultad de Ciencias, Facultad de Química, Universidad de la República, General Flores 2124, 11800, Montevideo, Uruguay.
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8
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Yeung H, Squire CJ, Yosaatmadja Y, Panjikar S, López G, Molina A, Baker EN, Harris PWR, Brimble MA. Radiation Damage and Racemic Protein Crystallography Reveal the Unique Structure of the GASA/Snakin Protein Superfamily. Angew Chem Int Ed Engl 2016; 55:7930-3. [DOI: 10.1002/anie.201602719] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Ho Yeung
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
| | - Christopher J. Squire
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
| | - Yuliana Yosaatmadja
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
| | - Santosh Panjikar
- Australian Synchrotron; 800 Blackburn Road Clayton Victoria 3168 Australia
| | - Gemma López
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA); Universidad Politécnica de Madrid (UPM); Campus Montegancedo, M-40 (Km 38) 28223-Pozuelo de Alarcón Madrid Spain
| | - Antonio Molina
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA); Universidad Politécnica de Madrid (UPM); Campus Montegancedo, M-40 (Km 38) 28223-Pozuelo de Alarcón Madrid Spain
| | - Edward N. Baker
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
| | - Paul W. R. Harris
- School of Chemical Sciences; The University of Auckland; 23 Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
| | - Margaret A. Brimble
- School of Chemical Sciences; The University of Auckland; 23 Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
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9
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Yeung H, Squire CJ, Yosaatmadja Y, Panjikar S, López G, Molina A, Baker EN, Harris PWR, Brimble MA. Radiation Damage and Racemic Protein Crystallography Reveal the Unique Structure of the GASA/Snakin Protein Superfamily. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201602719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ho Yeung
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
| | - Christopher J. Squire
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
| | - Yuliana Yosaatmadja
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
| | - Santosh Panjikar
- Australian Synchrotron; 800 Blackburn Road Clayton Victoria 3168 Australia
| | - Gemma López
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA); Universidad Politécnica de Madrid (UPM); Campus Montegancedo, M-40 (Km 38) 28223-Pozuelo de Alarcón Madrid Spain
| | - Antonio Molina
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA); Universidad Politécnica de Madrid (UPM); Campus Montegancedo, M-40 (Km 38) 28223-Pozuelo de Alarcón Madrid Spain
| | - Edward N. Baker
- School of Biological Sciences; The University of Auckland; 3A Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
| | - Paul W. R. Harris
- School of Chemical Sciences; The University of Auckland; 23 Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
| | - Margaret A. Brimble
- School of Chemical Sciences; The University of Auckland; 23 Symonds St Auckland Central 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery; Thomas Building Level 2; 3A Symonds St Auckland Central 1010 New Zealand
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10
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Tam JP, Wang S, Wong KH, Tan WL. Antimicrobial Peptides from Plants. Pharmaceuticals (Basel) 2015; 8:711-57. [PMID: 26580629 PMCID: PMC4695807 DOI: 10.3390/ph8040711] [Citation(s) in RCA: 283] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/06/2015] [Accepted: 09/01/2015] [Indexed: 12/25/2022] Open
Abstract
Plant antimicrobial peptides (AMPs) have evolved differently from AMPs from other life forms. They are generally rich in cysteine residues which form multiple disulfides. In turn, the disulfides cross-braced plant AMPs as cystine-rich peptides to confer them with extraordinary high chemical, thermal and proteolytic stability. The cystine-rich or commonly known as cysteine-rich peptides (CRPs) of plant AMPs are classified into families based on their sequence similarity, cysteine motifs that determine their distinctive disulfide bond patterns and tertiary structure fold. Cystine-rich plant AMP families include thionins, defensins, hevein-like peptides, knottin-type peptides (linear and cyclic), lipid transfer proteins, α-hairpinin and snakins family. In addition, there are AMPs which are rich in other amino acids. The ability of plant AMPs to organize into specific families with conserved structural folds that enable sequence variation of non-Cys residues encased in the same scaffold within a particular family to play multiple functions. Furthermore, the ability of plant AMPs to tolerate hypervariable sequences using a conserved scaffold provides diversity to recognize different targets by varying the sequence of the non-cysteine residues. These properties bode well for developing plant AMPs as potential therapeutics and for protection of crops through transgenic methods. This review provides an overview of the major families of plant AMPs, including their structures, functions, and putative mechanisms.
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Affiliation(s)
- James P Tam
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| | - Shujing Wang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
- Department of Pharmacology and Pharmaceutical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China.
| | - Ka H Wong
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| | - Wei Liang Tan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
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11
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Harris PWR, Yang SH, Molina A, López G, Middleditch M, Brimble MA. Plant antimicrobial peptides snakin-1 and snakin-2: chemical synthesis and insights into the disulfide connectivity. Chemistry 2014; 20:5102-10. [PMID: 24644073 DOI: 10.1002/chem.201303207] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 01/19/2014] [Indexed: 11/12/2022]
Abstract
Antimicrobial peptides and proteins represent an important class of plant defensive compounds against pathogens and provide a rich source of lead compounds in the field of drug discovery. We describe the effective preparation of the cysteine-rich snakin-1 and -2 antimicrobial peptides by using a combination of solid-phase synthesis and native chemical ligation. A subsequent cysteine/cystine mediated oxidative folding to form the six internal disulfide bonds concurrently gave the folded proteins in 40-50 % yield. By comparative evaluation of mass spectrometry, HPLC, biological data and trypsin digest mapping of folded synthetic snakin-2 compared to natural snakin-2, we demonstrated that synthetic snakin-2 possesses full antifungal activity and displayed similar chromatographic behaviour to natural snakin-2. Trypsin digest analysis allowed tentative assignment of three of the purported six disulfide bonds.
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Affiliation(s)
- Paul W R Harris
- School of Chemical Sciences, The University of Auckland, 23 Symonds St., Auckland 1142 (New Zealand), Fax: (+64) 93737422; Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, Auckland 1142 (New Zealand).
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12
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Ryazantsev DY, Rogozhin EA, Dimitrieva TV, Drobyazina PE, Khadeeva NV, Egorov TA, Grishin EV, Zavriev SK. A novel hairpin-like antimicrobial peptide from barnyard grass (Echinochloa crusgalli L.) seeds: Structure-functional and molecular-genetics characterization. Biochimie 2013; 99:63-70. [PMID: 24275143 DOI: 10.1016/j.biochi.2013.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 11/08/2013] [Indexed: 11/26/2022]
Abstract
A novel plant hairpin-like defense polypeptide named EcAMP3 was isolated from latent barnyard grass (Echinochloa crusgalli L.) seeds. The native peptide and its recombinant analogue were characterized. EcAMP3 displays antifungal and antibacterial activity in vitro. The gene family encoding EcAMPs precursor protein was also characterized; the genes and pseudogenes of this family show 97-100% homology. Every member of EcAMPs precursor family contains seven identical cysteine motifs: C1XXXC2(11-13)C3XXXC4. One of those motifs corresponds to the isolated peptide. EcAMP3 is the first member of the plant hairpin-like peptide family that inhibits the growth of phytopathogenic bacteria. Obtained results can explain the nature of the complex resistance of barnyard grass to a variety of pathogenic microorganisms.
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Affiliation(s)
- Dmitry Yu Ryazantsev
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
| | - Eugene A Rogozhin
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
| | - Tatiana V Dimitrieva
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
| | - Polina E Drobyazina
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation; All-Russian Research Institute of Biotechnology, Russian Academy of Agricultural Sciences, ul. Timiryazevskaya 42, 127550 Moscow, Russian Federation.
| | - Natalia V Khadeeva
- Vavilov Institute of General Genetics, Russian Academy of Sciences, ul. Gubkina 3, 117809 Moscow, Russian Federation.
| | - Tsezi A Egorov
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation
| | - Eugene V Grishin
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
| | - Sergey K Zavriev
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
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13
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Ayroza G, Ferreira ILC, Sayegh RSR, Tashima AK, da Silva Junior PI. Juruin: an antifungal peptide from the venom of the Amazonian Pink Toe spider, Avicularia juruensis, which contains the inhibitory cystine knot motif. Front Microbiol 2012; 3:324. [PMID: 22973266 PMCID: PMC3437525 DOI: 10.3389/fmicb.2012.00324] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 08/20/2012] [Indexed: 01/26/2023] Open
Abstract
The aim of this study was to screen the venom of the theraposid spider Avicularia juruensis for the identification of antimicrobial peptides (AMPs) which could be further used as prototypes for drug development. Eleven AMPs, named juruentoxins, with molecular weight ranging from 3.5 to 4.5 kDa, were identified by mass spectrometry after the soluble venom was separated by high performance liquid chromatography. Juruentoxins have a putative inhibitory cystine knot (ICK) motif, generally found in neurotoxins, which are also resistant to proteolysis. One juruentoxin that has 38 amino acid residues and three disulfide bonds were characterized, to which we proposed the name Juruin. Based on liquid growth inhibition assays, it has potent antifungal activity in the micromolar range. Importantly, Juruin lacks haemolytic activity on human erythrocytes at the antimicrobial concentrations. Based on the amino acid sequence, it is highly identical to the insecticidal peptides from the theraposid spiders Selenocosmia huwena, Chilobrachys jingzhao, and Haplopelma schmidti from China, indicating they belong to a group of conserved toxins which are likely to inhibit voltage-gated ion channels. Juruin is a cationic AMP, and Lys22 and Lys23 show maximum positive charge localization that might be important for receptor recognition. Although it shows marked sequence similarity to neurotoxic peptides, Juruin is a novel exciting molecule with potent antifungal activity, which could be used as a novel template for development of drugs against clinical resistant fungi strains.
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Affiliation(s)
- Gabriela Ayroza
- Laboratório Especial de Toxinologia Aplicada, Instituto Butantan São Paulo, Brazil
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14
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15
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Cerasoli E, Ravi J, Gregor C, Hussain R, Siligardi G, Martyna G, Crain J, Ryadnov MG. Membrane mediated regulation in free peptides of HIV-1 gp41: minimal modulation of the hemifusion phase. Phys Chem Chem Phys 2012; 14:1277-85. [DOI: 10.1039/c1cp23155c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Torrent M, Pulido D, de la Torre BG, García-Mayoral MF, Nogués MV, Bruix M, Andreu D, Boix E. Refining the eosinophil cationic protein antibacterial pharmacophore by rational structure minimization. J Med Chem 2011; 54:5237-44. [PMID: 21696142 DOI: 10.1021/jm200701g] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Sequence analysis of eosinophil cationic protein (ECP), a ribonuclease of broad antimicrobial activity, allowed identification of residues 1-45 as the antimicrobial domain. We have further dissected ECP(1-45) with a view to defining the minimal requirements for antimicrobial activity. Structure-based downsizing has focused on both α-helices of ECP(1-45) and yielded analogues with substantial potency against Gram-negative and -positive strains. Analogues ECP(8-36) and ECP(6-17)-Ahx-(23-36) (Ahx, 6-aminohexanoic acid) involve 36% and 40% size reduction relative to (1-45), respectively, and display a remarkably ECP-like antimicrobial profile. Both retain segments required for self-aggregation and lipolysaccharide binding, as well as the bacterial agglutination ability of parent ECP. Analogue (6-17)-Ahx-(23-36), in particular, is shown by NMR to preserve the helical traits of the native 8-16 (α1) and 33-36 (α2) regions and can be proposed as the minimal structure capable of reproducing the activity of the entire protein.
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Affiliation(s)
- Marc Torrent
- Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, E-08193 Cerdanyola del Vallès, Spain
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17
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Nolde SB, Vassilevski AA, Rogozhin EA, Barinov NA, Balashova TA, Samsonova OV, Baranov YV, Feofanov AV, Egorov TA, Arseniev AS, Grishin EV. Disulfide-stabilized helical hairpin structure and activity of a novel antifungal peptide EcAMP1 from seeds of barnyard grass (Echinochloa crus-galli). J Biol Chem 2011; 286:25145-53. [PMID: 21561864 DOI: 10.1074/jbc.m110.200378] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study presents purification, activity characterization, and (1)H NMR study of the novel antifungal peptide EcAMP1 from kernels of barnyard grass Echinochloa crus-galli. The peptide adopts a disulfide-stabilized α-helical hairpin structure in aqueous solution and thus represents a novel fold among naturally occurring antimicrobial peptides. Micromolar concentrations of EcAMP1 were shown to inhibit growth of several fungal phytopathogens. Confocal microscopy revealed intensive EcAMP1 binding to the surface of fungal conidia followed by internalization and accumulation in the cytoplasm without disturbance of membrane integrity. Close spatial structure similarity between EcAMP1, the trypsin inhibitor VhTI from seeds of Veronica hederifolia, and some scorpion and cone snail toxins suggests natural elaboration of different functions on a common fold.
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Affiliation(s)
- Svetlana B Nolde
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation
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18
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Oard SV. Deciphering a mechanism of membrane permeabilization by α-hordothionin peptide. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:1737-45. [PMID: 21315063 DOI: 10.1016/j.bbamem.2011.02.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Revised: 01/19/2011] [Accepted: 02/01/2011] [Indexed: 11/19/2022]
Abstract
α-Hordothionin (αHTH) belongs to thionins, the plant antimicrobial peptides with membrane-permeabilizing activity which is associated with broad-range antimicrobial activity. Experimental data have revealed a phospholipid-binding site and indicated formation of ion channels as well as membrane disruption activity of thionin. However, the mechanism of membrane permeabilization by thionin remained unknown. Here it is shown that thionin is a small water-selective channel. Unbiased high-precision molecular modeling revealed formation of a water-selective pore running through the αHTH double α-helix core when the peptide interacted with anions. Anion-induced unfolding of the C-end of the α2-helix opened a pore mouth. The pore started at the α2 C-end between the hydrophilic and the hydrophobic regions of the peptide surface and ended in the middle of the unique hydrophobic region at the C-end of the α1-helix. Highly conserved residues including cysteines and tyrosine lined the pore walls. A large positive electrostatic potential accumulated inside the pore. The narrow pore was, nonetheless, sufficient to accommodate at least one water molecule along the channel except for two constriction sites. Both constriction sites were formed by residues participating in the phospholipid-binding site. The channel properties resembled that of aquaporins with two selectivity filters, one at the entrance, inside the α2 C-end cavity, and a second in the middle of the channel. It is proposed that the αHTH water channel delivers water molecules to the bilayer center that leads to local membrane disruption. The proposed mechanism of membrane permeabilization by thionins explains seemingly controversial experimental data.
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Affiliation(s)
- Svetlana V Oard
- School of Plant, Environmental, and Soil Sciences, Louisiana State Agricultural Center, Louisiana State University, Baton Rouge, LA 70803, USA.
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19
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Structural changes induced in thionins by chloride anions as determined by molecular dynamics simulations. Biophys Chem 2010; 147:42-52. [DOI: 10.1016/j.bpc.2009.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 12/21/2009] [Accepted: 12/23/2009] [Indexed: 11/23/2022]
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20
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de Medeiros LN, Angeli R, Sarzedas CG, Barreto-Bergter E, Valente AP, Kurtenbach E, Almeida FCL. Backbone dynamics of the antifungal Psd1 pea defensin and its correlation with membrane interaction by NMR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1798:105-13. [PMID: 19632194 DOI: 10.1016/j.bbamem.2009.07.013] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 06/25/2009] [Accepted: 07/08/2009] [Indexed: 11/26/2022]
Abstract
Plant defensins are cysteine-rich cationic peptides, components of the innate immune system. The antifungal sensitivity of certain exemplars was correlated to the level of complex glycosphingolipids in the membrane of fungi strains. Psd1 is a 46 amino acid residue defensin isolated from pea seeds which exhibit antifungal activity. Its structure is characterized by the so-called cysteine-stabilized alpha/beta motif linked by three loops as determined by two-dimensional NMR. In the present work we explored the measurement of heteronuclear Nuclear Overhauser Effects, R1 and R2 (15)N relaxation ratios, and chemical shift to probe the backbone dynamics of Psd1 and its interaction with membrane mimetic systems with phosphatidylcholine (PC) or dodecylphosphocholine (DPC) with glucosylceramide (CMH) isolated from Fusarium solani. The calculated R2 values predicted a slow motion around the highly conserved among Gly12 residue and also in the region of the Turn3 His36-Trp38. The results showed that Psd1 interacts with vesicles of PC or PC:CMH in slightly different forms. The interaction was monitored by chemical shift perturbation and relaxation properties. Using this approach we could map the loops as the binding site of Psd1 with the membrane. The major binding epitope showed conformation exchange properties in the mus-ms timescale supporting the conformation selection as the binding mechanism. Moreover, the peptide corresponding to part of Loop1 (pepLoop1: Gly12 to Ser19) is also able to interact with DPC micelles acquiring a stable structure and in the presence of DPC:CMH the peptide changes to an extended conformation, exhibiting NOE mainly with the carbohydrate and ceramide parts of CMH.
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Affiliation(s)
- Luciano Neves de Medeiros
- Instituto de Biofísica Carlos Chagas Filho, Programa de Biologia Molecular e Estrutural, Universidade Federal do Rio de Janeiro, Brazil
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21
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Rádis-Baptista G, de la Torre BG, Andreu D. A Novel Cell-Penetrating Peptide Sequence Derived by Structural Minimization of a Snake Toxin Exhibits Preferential Nucleolar Localization. J Med Chem 2008; 51:7041-4. [DOI: 10.1021/jm8009475] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Gandhi Rádis-Baptista
- Department of Experimental and Health Sciences, Pompeu Fabra University, Dr Aiguader, 80, E-08003 Barcelona, Spain, and Department of Biochemistry, Center for Biological Sciences, Federal University of Pernambuco, Cidade Universitária, 50732-970 Recife-PE, Brazil
| | - Beatriz G. de la Torre
- Department of Experimental and Health Sciences, Pompeu Fabra University, Dr Aiguader, 80, E-08003 Barcelona, Spain, and Department of Biochemistry, Center for Biological Sciences, Federal University of Pernambuco, Cidade Universitária, 50732-970 Recife-PE, Brazil
| | - David Andreu
- Department of Experimental and Health Sciences, Pompeu Fabra University, Dr Aiguader, 80, E-08003 Barcelona, Spain, and Department of Biochemistry, Center for Biological Sciences, Federal University of Pernambuco, Cidade Universitária, 50732-970 Recife-PE, Brazil
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22
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Marcos JF, Muñoz A, Pérez-Payá E, Misra S, López-García B. Identification and rational design of novel antimicrobial peptides for plant protection. ANNUAL REVIEW OF PHYTOPATHOLOGY 2008; 46:273-301. [PMID: 18439131 DOI: 10.1146/annurev.phyto.121307.094843] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Peptides and small proteins exhibiting antimicrobial activity have been isolated from many organisms ranging from insects to humans, including plants. Their role in defense is established, and their use in agriculture was already being proposed shortly after their discovery. However, some natural peptides have undesirable properties that complicate their application. Advances in peptide synthesis and high-throughput activity screening have made possible the de novo and rational design of novel peptides with improved properties. This review summarizes findings in the identification and design of short antimicrobial peptides with activity against plant pathogens, and will discuss alternatives for their heterologous production suited to plant disease control. Recent studies suggest that peptide antimicrobial action is not due solely to microbe permeation as previously described, but that more subtle factors might account for the specificity and absence of toxicity of some peptides. The elucidation of the mode of action and interaction with microbes will assist the improvement of peptide design with a view to targeting specific problems in agriculture and providing new tools for plant protection.
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Affiliation(s)
- Jose F Marcos
- Departamento de Ciencia de los Alimentos, Instituto de Agroquímica y Tecnología de Alimentos-CSIC, 46100 Burjassot, Spain.
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23
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Oard S, Karki B, Enright F. Is there a difference in metal ion-based inhibition between members of thionin family: Molecular dynamics simulation study. Biophys Chem 2007; 130:65-75. [PMID: 17703869 DOI: 10.1016/j.bpc.2007.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 07/18/2007] [Accepted: 07/19/2007] [Indexed: 10/23/2022]
Abstract
Thionins have a considerable potential as antimicrobial compounds although their application may be restricted by metal ion-based inhibition of membrane permeabilizing activity. We previously reported the properties associated with the proposed mechanism of metal ion-based inhibition of beta-purothionin. In this study, we investigated the effects of metal ions on alpha-hordothionin which differs from beta-purothionin by eight out of 45 residues. Three of the differing residues are thought to be involved in the mechanism of metal ion-based inhibition in beta-purothionin. The structure and dynamics of alpha-hordothionin were explored using unconstrained molecular dynamics (MD) simulations in explicit water as a function of metal ions. Although the global fold is almost identical to that of beta-purothionin, alpha-hordothionin displays reduced fluctuating motions. Moreover, alpha-hordothionin is more resistant to the presence of metal ions than beta-purothionin. Mg(+2) ions do not affect alpha-hordothionin, whereas K(+) ions induce perturbations in the alpha2 helix, modify dynamics and electrostatic properties. Nevertheless, these changes are considerably smaller than those in beta-purothionin. The proposed mechanism of metal ion-based inhibition involves the hydrogen bonding network of Arg5-Arg30-Gly27, which regulates dynamic unfolding of the alpha2 C-end which is similar to beta-purothionin response. The key residues responsible for the increased resistance for alpha-hordothionin are Gly27 and Gly42 which replace Asn27 and Asp42 involved into the mechanism of metal ion-based inhibition in beta-purothionin. Comparison of MD simulations of alpha-hordothionin with beta-purothionin reveals dynamic properties which we believe are intrinsic properties of thionins with four disulphide bonds.
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Affiliation(s)
- Svetlana Oard
- LSU AgCenter Biotechnology Laboratory, Louisiana State University, 115 Wilson Bldg., LSU, Baton Rouge, LA 70803, USA.
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24
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Machado A, Sforça ML, Miranda A, Daffre S, Pertinhez TA, Spisni A, Miranda MTM. Truncation of amidated fragment 33-61 of bovine α-hemoglobin: Effects on the structure and anticandidal activity. Biopolymers 2007; 88:413-26. [PMID: 17245752 DOI: 10.1002/bip.20688] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Peptides derived from endogenous hemoglobin play important biological roles in a variety of living systems. In previous works we showed that the fragment 33-61 of bovine alpha-hemoglobin (Hb33-61) and its C-terminus amidated analogue (Hb33-61a) exhibit antimicrobial activity and we determined the 3D structure of Hb33-61a bound to sodium dodecyl sulfate micelles. Here we report that Hb33-61a is lethal to Candida albicans at 6.25 microM probably through disruption of its plasma membrane. In addition, we show that, even when used at 50 microM, Hb33- 61a produces low hemolysis (16% +/- 3.0%). Recognizing that one of the key steps to study new compounds with potential pharmaceutical application is to identify the structural elements essential to express biological activity, we also investigated the anticandidal activity of Hb33- 61a fragments. The results indicated that Hb40-61a exhibits the same minimal inhibitory concentration as Hb33-61a, whereas Hb33-52a and Hb48-61a are significantly less active. Noteworthy, for all the peptides tested, we observed that C-terminus amidation produces a potentiation of their anticandidal activity and we associate that increased biological activity to a preferred structural and spatial organization of the C-terminal region favored by amidation. Finally, the data show that the most active peptides (Hb33-61a and Hb40-61a) are characterized by a central hinge joining the C-terminal region that presents, containing a beta-turn, followed by and a helical element, to the N-terminal region that presents only a beta-turn. We hypothesize that these two structured regions, by fluctuating independently in the lipid environment, may act in a coordinated fashion disrupting the yeast plasma membrane.
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Affiliation(s)
- Alessandra Machado
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, PO Box 26077, Brazil
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25
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Abstract
We identified 1113 articles (103 reviews, 1010 primary research articles) published in 2005 that describe experiments performed using commercially available optical biosensors. While this number of publications is impressive, we find that the quality of the biosensor work in these articles is often pretty poor. It is a little disappointing that there appears to be only a small set of researchers who know how to properly perform, analyze, and present biosensor data. To help focus the field, we spotlight work published by 10 research groups that exemplify the quality of data one should expect to see from a biosensor experiment. Also, in an effort to raise awareness of the common problems in the biosensor field, we provide side-by-side examples of good and bad data sets from the 2005 literature.
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Affiliation(s)
- Rebecca L Rich
- Center for Biomolecular Interaction Analysis, University of Utah, Salt Lake City, UT 84132, USA
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26
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Pelegrini PB, Franco OL. Plant gamma-thionins: novel insights on the mechanism of action of a multi-functional class of defense proteins. Int J Biochem Cell Biol 2005; 37:2239-53. [PMID: 16084753 DOI: 10.1016/j.biocel.2005.06.011] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Revised: 05/13/2005] [Accepted: 01/26/2005] [Indexed: 11/27/2022]
Abstract
This review focuses on the first plant defense protein class described in literature, with growth inhibition activity toward pathogens. These peptides were named gamma-thionins or defensins, which are small proteins that can be classified into four main subtypes according to their specific functions. Gamma-thionins are small cationic peptides with different and special abilities. They are able to inhibit digestive enzymes or act against bacteria and/or fungi. Current research in this area focuses particularly these two last targets, being the natural crop plant defenses improved through the use of transgenic technology. Here, we will compare primary and tertiary structures of gamma-thionins and also will analyze their similarities to scorpion toxins and insect defensins. This last comparison offers some hypothesis for gamma-thionins mechanisms of action against certain pathogens. This specific area has benefited from the recent determination of many gamma-thionin structures. Furthermore, we also summarize molecular interactions between plant gamma-thionins and fungi receptors, which include membrane proteins and lipids, shedding some light over pathogen resistance. Researches on gamma-thionins targets could help on plant genetic improvement for production of increased resistance toward pathogens. Thus, positive results recently obtained for transgenic plants and future prospects in the area are also approached. Finally, gamma-thionins activity has also been studied for future drug development, capable of inhibit tumor cell growth in human beings.
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Affiliation(s)
- Patrícia B Pelegrini
- Centro de Análises Proteômicas e Bioquímicas, Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, SGAN Quadra 916, Módulo B, Av. W5 Norte 70.790-160 Asa Norte Brasília/DF, Brazil
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27
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Vila-Perelló M, Andreu D. Characterization and structural role of disulfide bonds in a highly knotted thionin from Pyrularia pubera. Biopolymers 2005; 80:697-707. [PMID: 15765547 DOI: 10.1002/bip.20270] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Disulfide bonds play a crucial role in the stabilization of the amphipathic folding of the diverse families of cysteine-rich antimicrobial peptides. The determination of cysteine pairings in these peptides has largely depended on sequence homology criteria, since the classical methods of disulfide bond characterization, which usually require proteolysis as a first step, encounter serious drawbacks derived from the tight folding and the presence of vicinal cysteines. We have chosen the Pyrularia pubera thionin, a 47-residue peptide with four internal disulfides and a remarkable resistance to most proteases, as a representative member of this type of cysteine-rich peptides and have shown that a combination of partial reduction and cyanylation readily allows the determination of its disulfide bonds. We have also studied by molecular dynamics and a combination of partial reduction and proteolysis the role of disulfide bonds in the stabilization of the tridimensional structure of this thionin and found a good agreement with our partial reduction data, suggesting that removal of only one disulfide bond is enough to significantly alter the folding of the peptide.
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Affiliation(s)
- Miquel Vila-Perelló
- Department of Experimental and Health Sciences, Pompeu Fabra University, Dr. Aiguader, 80, E-08003 Barcelona, Spain
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