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Sankaran SV, Saiba R, Sikdar S, Vemparala S. Correlation Between Antimicrobial Structural Classes and Membrane Partitioning: Role of Emerging Lipid Packing Defects. J Membr Biol 2024:10.1007/s00232-024-00318-z. [PMID: 39037449 DOI: 10.1007/s00232-024-00318-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Accepted: 07/09/2024] [Indexed: 07/23/2024]
Abstract
In this study, a combination of bioinformatics and molecular dynamics simulations is employed to investigate the partitioning behavior of different classes of antimicrobial peptides (AMPs) into model membranes. The main objective is to identify any correlations between the structural characteristics of AMPs and their membrane identification and early-stage partitioning mechanisms. The simulation results reveal distinct membrane interactions among the various structural classes of AMPs, particularly in relation to the generation and subsequent interaction with lipid packing defects. Notably, AMPs with a structure-less coil conformation generate a higher number of deep and shallow defects, which are larger in size compared to other classes of AMPs. AMPs with helical component demonstrated the deepest insertion into the membrane. On the other hand, AMPs with a significant percentage of beta sheets tend to adsorb onto the membrane surface, suggesting a potentially distinct partitioning mechanism attributed to their structural rigidity. These findings highlight the diverse membrane interactions and partitioning mechanisms exhibited by different structural classes of AMPs.
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Affiliation(s)
- S V Sankaran
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, Tamil Nadu, 600113, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400094, India
| | - Roni Saiba
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, Tamil Nadu, 600113, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400094, India
| | - Samapan Sikdar
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, Tamil Nadu, 600113, India.
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400094, India.
| | - Satyavani Vemparala
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, Tamil Nadu, 600113, India.
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, Maharashtra, 400094, India.
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Loffredo MR, Nencioni L, Mangoni ML, Casciaro B. Antimicrobial peptides for novel antiviral strategies in the current post-COVID-19 pandemic. J Pept Sci 2024; 30:e3534. [PMID: 37501572 DOI: 10.1002/psc.3534] [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: 04/28/2023] [Revised: 06/30/2023] [Accepted: 07/03/2023] [Indexed: 07/29/2023]
Abstract
The recent pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted how urgent and necessary the discovery of new antiviral compounds is for novel therapeutic approaches. Among the various classes of molecules with antiviral activity, antimicrobial peptides (AMPs) of innate immunity are among the most promising ones, mainly due to their different mechanisms of action against viruses and additional biological properties. In this review, the main physicochemical characteristics of AMPs are described, with particular interest toward peptides derived from amphibian skin. Living in aquatic and terrestrial environments, amphibians are one of the richest sources of AMPs with different primary and secondary structures. Besides describing the various antiviral activities of these peptides and the underlying mechanism, this review aims at emphasizing the high potential of these small molecules for the development of new antiviral agents that likely reduce the selection of resistant strains.
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Affiliation(s)
- Maria Rosa Loffredo
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Lucia Nencioni
- Department of Public Health and Infectious Diseases, Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Maria Luisa Mangoni
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Bruno Casciaro
- Department of Biochemical Sciences "A. Rossi Fanelli", Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
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3
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Immunity in Sea Turtles: Review of a Host-Pathogen Arms Race Millions of Years in the Running. Animals (Basel) 2023; 13:ani13040556. [PMID: 36830343 PMCID: PMC9951749 DOI: 10.3390/ani13040556] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/05/2023] [Accepted: 01/20/2023] [Indexed: 02/08/2023] Open
Abstract
The immune system of sea turtles is not completely understood. Sea turtles (as reptiles) bridge a unique evolutionary gap, being ectothermic vertebrates like fish and amphibians and amniotes like birds and mammals. Turtles are ectotherms; thus, their immune system is influenced by environmental conditions like temperature and season. We aim to review the turtle immune system and note what studies have investigated sea turtles and the effect of the environment on the immune response. Turtles rely heavily on the nonspecific innate response rather than the specific adaptive response. Turtles' innate immune effectors include antimicrobial peptides, complement, and nonspecific leukocytes. The antiviral defense is understudied in terms of the diversity of pathogen receptors and interferon function. Turtles also mount adaptive responses to pathogens. Lymphoid structures responsible for lymphocyte activation and maturation are either missing in reptiles or function is affected by season. Turtles are a marker of health for their marine environment, and their immune system is commonly dysregulated because of disease or contaminants. Fibropapillomatosis (FP) is a tumorous disease that afflicts sea turtles and is thought to be caused by a virus and an environmental factor. We aim, by exploring the current understanding of the immune system in turtles, to aid the investigation of environmental factors that contribute to the pathogenesis of this disease and provide options for immunotherapy.
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Oluremi BB, Osamudiamen PM, Adeniji JA, Aiyelaagbe OO. Anti-Measles Virus Activity of 4-Hydroxy-3-Methoxy Benzaldehyde (Vanillin) isolated from Xylopia aethiopica (Dunal) A. Rich. SCIENTIFIC AFRICAN 2022. [DOI: 10.1016/j.sciaf.2022.e01506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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5
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Vecchioni L, Pace A, Sucato A, Berlinghieri F, Cambera I, Visconti G, Hochscheid S, Arculeo M, Alduina R. Unveiling the egg microbiota of the loggerhead sea turtle Caretta caretta in nesting beaches of the Mediterranean Sea. PLoS One 2022; 17:e0268345. [PMID: 35617269 PMCID: PMC9135217 DOI: 10.1371/journal.pone.0268345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 04/27/2022] [Indexed: 12/01/2022] Open
Abstract
Microbes have central roles in the development and health of animals, being the introduction of specific microbial species a potential conservation strategy to protect animals from emerging diseases. Thus, insight into the microbiota of the species and their habitats is essential. In this manuscript, we report for the first time the bacterial composition of all the components (eggshells of hatched and unhatched eggs, internal content of unhatched eggs, intestinal content of hatchling and pipping sea turtles, and sand) of three nesting beaches of Caretta caretta along the Italian coasts of the Mediterranean Sea. The analysis of 26 amplicon samples was carried out using next-generation sequencing analysis, targeting V3–V4 regions of the bacterial 16S rRNA gene. Samples featured mainly Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes, whose percentages depended on the sample type. Our results showed that, although from different sampling sites, the internal content of the unhatched eggs, intestinal content of hatchling and pipping sea turtles share the microbiota, which was yet different from that of eggshells and sand of the same nesting beach. This study suggests the maternal and environmental influence alongside a protective role of eggshells in shaping the egg microbiota of Caretta caretta sea turtles.
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Affiliation(s)
- Luca Vecchioni
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Antonino Pace
- Stazione Zoologica Anton Dohrn, Department of Marine Animal Conservation and Public Engagement, Marine Turtle Research Group, Portici (NA), Italy
| | - Arianna Sucato
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Flavia Berlinghieri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Irene Cambera
- Pelagie Islands Marine Protected Area, Municipality of Lampedusa and Linosa, Agrigento, Italy
| | - Giulia Visconti
- Pelagie Islands Marine Protected Area, Municipality of Lampedusa and Linosa, Agrigento, Italy
| | - Sandra Hochscheid
- Stazione Zoologica Anton Dohrn, Department of Marine Animal Conservation and Public Engagement, Marine Turtle Research Group, Portici (NA), Italy
| | - Marco Arculeo
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Rosa Alduina
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
- * E-mail:
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Bin Hafeez A, Jiang X, Bergen PJ, Zhu Y. Antimicrobial Peptides: An Update on Classifications and Databases. Int J Mol Sci 2021; 22:11691. [PMID: 34769122 PMCID: PMC8583803 DOI: 10.3390/ijms222111691] [Citation(s) in RCA: 116] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/24/2021] [Accepted: 10/25/2021] [Indexed: 02/06/2023] Open
Abstract
Antimicrobial peptides (AMPs) are distributed across all kingdoms of life and are an indispensable component of host defenses. They consist of predominantly short cationic peptides with a wide variety of structures and targets. Given the ever-emerging resistance of various pathogens to existing antimicrobial therapies, AMPs have recently attracted extensive interest as potential therapeutic agents. As the discovery of new AMPs has increased, many databases specializing in AMPs have been developed to collect both fundamental and pharmacological information. In this review, we summarize the sources, structures, modes of action, and classifications of AMPs. Additionally, we examine current AMP databases, compare valuable computational tools used to predict antimicrobial activity and mechanisms of action, and highlight new machine learning approaches that can be employed to improve AMP activity to combat global antimicrobial resistance.
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Affiliation(s)
- Ahmer Bin Hafeez
- Centre of Biotechnology and Microbiology, University of Peshawar, Peshawar 25120, Pakistan;
| | - Xukai Jiang
- Infection and Immunity Program, Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; (X.J.); (P.J.B.)
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China
| | - Phillip J. Bergen
- Infection and Immunity Program, Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; (X.J.); (P.J.B.)
| | - Yan Zhu
- Infection and Immunity Program, Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; (X.J.); (P.J.B.)
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Sumon TA, Hussain MA, Hasan M, Rashid A, Abualreesh MH, Jang WJ, Sharifuzzaman SM, Brown CL, Lee EW, Hasan MT. Antiviral peptides from aquatic organisms: Functionality and potential inhibitory effect on SARS-CoV-2. AQUACULTURE (AMSTERDAM, NETHERLANDS) 2021; 541:736783. [PMID: 33883784 PMCID: PMC8049179 DOI: 10.1016/j.aquaculture.2021.736783] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 02/26/2021] [Accepted: 04/14/2021] [Indexed: 05/06/2023]
Abstract
Several antiviral peptides (AVPs) from aquatic organisms have been effective in interfering with the actions of infectious viruses, such as Human Immunodeficiency Virus-1 and Herpes Simplex Virus-1 and 2. AVPs are able to block viral attachment or entry into host cells, inhibit internal fusion or replication events by suppressing viral gene transcription, and prevent viral infections by modulating host immunity. Therefore, as promising therapeutics, the potential of aquatic AVPs for use against the COVID-19 pandemic caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is considered. At present no therapeutic drugs are yet available. A total of 32 AVPs derived from fish and shellfish species are discussed in this review paper with notes on their properties and mechanisms of action in the inhibition of viral diseases both in humans and animals, emphasizing on SARS-CoV-2. The molecular structure of novel SARS-CoV-2 with its entry mechanisms, clinical signs and symptoms are also discussed. In spite of only a few study of these AVPs against SARS-CoV-2, aquatic AVPs properties and infection pathways (entry, replication and particle release) into coronaviruses are linked in this paper to postulate an analysis of their potential but unconfirmed actions to impair SARS-CoV-2 infection in humans.
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Affiliation(s)
- Tofael Ahmed Sumon
- Department of Fish Health Management, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Md Ashraf Hussain
- Department of Fisheries Technology and Quality Control, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Mahmudul Hasan
- Department of Pharmaceuticals and Industrial Biotechnology, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Aminur Rashid
- Department of Aquaculture, Sylhet Agricultural University, Sylhet 3100, Bangladesh
| | - Muyassar Hamid Abualreesh
- Department of Marine Biology, Faculty of Marine Science, King Abdulaziz University, P.O. Box 80207, Jeddah 21589, Saudi Arabia
| | - Won Je Jang
- Biopharmaceutical Engineering Major, Division of Applied Bioengineering, Dong-Eui University, Busan 47340, Republic of Korea
| | - S M Sharifuzzaman
- Institute of Marine Sciences, University of Chittagong, Chittagong 4331, Bangladesh
| | - Christopher Lyon Brown
- FAO World Fisheries University Pilot Programme, Pukyong National University, Busan, South Korea
| | - Eun-Woo Lee
- Biopharmaceutical Engineering Major, Division of Applied Bioengineering, Dong-Eui University, Busan 47340, Republic of Korea
| | - Md Tawheed Hasan
- Department of Aquaculture, Sylhet Agricultural University, Sylhet 3100, Bangladesh
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Ashaolu TJ, Nawaz A, Walayat N, Khalifa I. Potential "biopeptidal" therapeutics for severe respiratory syndrome coronaviruses: a review of antiviral peptides, viral mechanisms, and prospective needs. Appl Microbiol Biotechnol 2021; 105:3457-3470. [PMID: 33876282 PMCID: PMC8054851 DOI: 10.1007/s00253-021-11267-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/25/2021] [Accepted: 04/04/2021] [Indexed: 01/10/2023]
Abstract
Although great advances have been made on large-scale manufacturing of vaccines and antiviral-based drugs, viruses persist as the major cause of human diseases nowadays. The recent pandemic of coronavirus disease-2019 (COVID-19) mounts a lot of stress on the healthcare sector and the scientific society to search continuously for novel components with antiviral possibility. Herein, we narrated the different tactics of using biopeptides as antiviral molecules that could be used as an interesting alternative to treat COVID-19 patients. The number of peptides with antiviral effects is still low, but such peptides already displayed huge potentials to become pharmaceutically obtainable as antiviral medications. Studies showed that animal venoms, mammals, plant, and artificial sources are the main sources of antiviral peptides, when bioinformatics tools are used. This review spotlights bioactive peptides with antiviral activities against human viruses, especially the coronaviruses such as severe acute respiratory syndrome (SARS) virus, Middle East respiratory syndrome (MERS) virus, and severe acute respiratory syndrome coronavirus 2 (SARS-COV-2 or SARS-nCOV19). We also showed the data about well-recognized peptides that are still under investigations, while presenting the most potent ones that may become medications for clinical use.
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Affiliation(s)
- Tolulope Joshua Ashaolu
- Institute of Research and Development, Duy Tan University, Da Nang, 550000 Vietnam
- Faculty of Environmental and Chemical Engineering, Duy Tan University, Da Nang, 550000 Vietnam
| | - Asad Nawaz
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, College of Agriculture, Yangzhou University, Yangzhou, People’s Republic of China
| | - Noman Walayat
- Department of Food Science and Engineering, College of Ocean, Zhejiang University of Technology, Hangzhou, People’s Republic of China
| | - Ibrahim Khalifa
- Food Technology Department, Faculty of Agriculture, Banha University, 13736, Moshtohor, Cairo, Egypt
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Villa TG, Abril AG, Sánchez S, de Miguel T, Sánchez-Pérez A. Animal and human RNA viruses: genetic variability and ability to overcome vaccines. Arch Microbiol 2021; 203:443-464. [PMID: 32989475 PMCID: PMC7521576 DOI: 10.1007/s00203-020-02040-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 06/29/2020] [Accepted: 09/12/2020] [Indexed: 02/06/2023]
Abstract
RNA viruses, in general, exhibit high mutation rates; this is mainly due to the low fidelity displayed by the RNA-dependent polymerases required for their replication that lack the proofreading machinery to correct misincorporated nucleotides and produce high mutation rates. This lack of replication fidelity, together with the fact that RNA viruses can undergo spontaneous mutations, results in genetic variants displaying different viral morphogenesis, as well as variation on their surface glycoproteins that affect viral antigenicity. This diverse viral population, routinely containing a variety of mutants, is known as a viral 'quasispecies'. The mutability of their virions allows for fast evolution of RNA viruses that develop antiviral resistance and overcome vaccines much more rapidly than DNA viruses. This also translates into the fact that pathogenic RNA viruses, that cause many diseases and deaths in humans, represent the major viral group involved in zoonotic disease transmission, and are responsible for worldwide pandemics.
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Affiliation(s)
- T G Villa
- Department of Microbiology, Faculty of Pharmacy, University of Santiago de Compostela, 5706, Santiago de Compostela, Spain.
| | - Ana G Abril
- Department of Microbiology, Faculty of Pharmacy, University of Santiago de Compostela, 5706, Santiago de Compostela, Spain
| | - S Sánchez
- Department of Microbiology, Faculty of Pharmacy, University of Santiago de Compostela, 5706, Santiago de Compostela, Spain
| | - T de Miguel
- Department of Microbiology, Faculty of Pharmacy, University of Santiago de Compostela, 5706, Santiago de Compostela, Spain
| | - A Sánchez-Pérez
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Sydney, NSW, 2006, Australia
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Santana FL, Estrada K, Ortiz E, Corzo G. Reptilian β-defensins: Expanding the repertoire of known crocodylian peptides. Peptides 2021; 136:170473. [PMID: 33309943 DOI: 10.1016/j.peptides.2020.170473] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/26/2020] [Accepted: 12/03/2020] [Indexed: 01/31/2023]
Abstract
One of the major families of host defense peptides (HDPs) in vertebrates are β-defensins. They constitute important components of innate immunity and have remained an interesting topic of research for more than two decades. While many β-defensin sequences in mammals and birds have been identified and their properties and functions characterized, β-defensin peptides from other groups of vertebrates, particularly reptiles, are still largely unexplored. In this review, we focus on reptilian β-defensins and summarize different aspects of their biology, such as their genomic organization, evolution, structure, and biological activities. Reptilian β-defensin genes exhibit similar genomic organization to birds and their number and gene structure are variable among different species. During the evolution of reptiles, several gene duplication and deletion events have occurred and the functional diversification of β-defensins has been mainly driven by positive selection. These peptides display broad antimicrobial activity in vitro, but a deeper understanding of their mechanisms of action in vivo, including their role as immunomodulators, is still lacking. Reptilian β-defensins constitute unique polypeptide sequences to expand our current understanding of innate immunity in these animals and elucidate core biological functions of this family of HDPs across amniotes.
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Affiliation(s)
- Felix L Santana
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, A.P. 510-3, Cuernavaca Mor., 62250, Mexico.
| | - Karel Estrada
- Unidad de Secuenciación Masiva y Bioinformática, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Ernesto Ortiz
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, A.P. 510-3, Cuernavaca Mor., 62250, Mexico
| | - Gerardo Corzo
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, A.P. 510-3, Cuernavaca Mor., 62250, Mexico.
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Contreras G, Shirdel I, Braun MS, Wink M. Defensins: Transcriptional regulation and function beyond antimicrobial activity. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 104:103556. [PMID: 31747541 DOI: 10.1016/j.dci.2019.103556] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 05/20/2023]
Abstract
Defensins are one the largest group of antimicrobial peptides and are part of the innate defence. Defensins are produced by animals, plants and fungi. In animals and plants, defensins can be constitutively or differentially expressed both locally or systemically which confer defence before and a stronger response after infection. Immune signalling pathways regulate the gene expression of defensins. These pathways include cellular receptors, which recognise pathogen-associated molecular patterns and are found both in plants and animals. After recognition, signalling pathways and, subsequently, transcriptional factors are activated. There is an increasing number of novel functions in defensins, such as immunomodulators and immune cell attractors. Identification of defensin triggers could help us to elucidate other new functions. The present article reviews the different elicitors of defensins with a main focus on human, fish and marine invertebrate defensins.
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Affiliation(s)
- Gabriela Contreras
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany.
| | - Iman Shirdel
- Marine Sciences Faculty, Tarbiat Modares University, Noor, Iran
| | - Markus Santhosh Braun
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Michael Wink
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany.
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Hansen IKØ, Isaksson J, Poth AG, Hansen KØ, Andersen AJC, Richard CSM, Blencke HM, Stensvåg K, Craik DJ, Haug T. Isolation and Characterization of Antimicrobial Peptides with Unusual Disulfide Connectivity from the Colonial Ascidian Synoicum turgens. Mar Drugs 2020; 18:md18010051. [PMID: 31940927 PMCID: PMC7024374 DOI: 10.3390/md18010051] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 11/16/2022] Open
Abstract
This study reports the isolation of two novel cysteine-rich antibacterial peptides, turgencin A and turgencin B, along with their oxidized derivatives, from the Arctic marine colonial ascidian Synoicum turgens. The peptides are post-translationally modified, containing six cysteines with an unusual disulfide connectivity of Cys1-Cys6, Cys2-Cys5, and Cys3-Cys4 and an amidated C-terminus. Furthermore, the peptides contain methionine residues resulting in the isolation of peptides with different degrees of oxidation. The most potent peptide, turgencin AMox1 with one oxidized methionine, displayed antimicrobial activity against both Gram-negative and Gram-positive bacteria with a minimum inhibitory concentration (MIC) as low as 0.4 µM against selected bacterial strains. In addition, the peptide inhibited the growth of the melanoma cancer cell line A2058 (IC50 = 1.4 µM) and the human fibroblast cell line MRC-5 (IC50 = 4.8 µM). The results from this study show that natural peptides isolated from marine tunicates have the potential to be promising drug leads.
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Affiliation(s)
- Ida K. Ø. Hansen
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway (C.S.M.R.); (H.-M.B.); (K.S.)
- Correspondence: (I.K.Ø.H.); (T.H.); Tel.: +47-77-64-92-66 (I.K.Ø.H.); +47-77-64-60-71 (T.H.)
| | - Johan Isaksson
- Department of Chemistry, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway;
| | - Aaron G. Poth
- Institute for Molecular Bioscience, The University of Queensland, Brisbane 4072, Queensland, Australia; (A.G.P.); (D.J.C.)
| | - Kine Ø. Hansen
- Marbio, UiT The Arctic University of Norway, Breivika, N-9037, Tromsø, Norway;
| | - Aaron J. C. Andersen
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway (C.S.M.R.); (H.-M.B.); (K.S.)
| | - Céline S. M. Richard
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway (C.S.M.R.); (H.-M.B.); (K.S.)
| | - Hans-Matti Blencke
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway (C.S.M.R.); (H.-M.B.); (K.S.)
| | - Klara Stensvåg
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway (C.S.M.R.); (H.-M.B.); (K.S.)
| | - David J. Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane 4072, Queensland, Australia; (A.G.P.); (D.J.C.)
| | - Tor Haug
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Breivika, N-9037 Tromsø, Norway (C.S.M.R.); (H.-M.B.); (K.S.)
- Correspondence: (I.K.Ø.H.); (T.H.); Tel.: +47-77-64-92-66 (I.K.Ø.H.); +47-77-64-60-71 (T.H.)
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Rodriguez A, Pedersen MØ, Villegas E, Rivas‐Santiago B, Villegas‐Moreno J, Amero C, Norton RS, Corzo G. Antimicrobial activity and structure of a consensus human β‐defensin and its comparison to a novel putative hBD10. Proteins 2019; 88:175-186. [DOI: 10.1002/prot.25785] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 07/09/2019] [Accepted: 07/12/2019] [Indexed: 02/05/2023]
Affiliation(s)
- Alexis Rodriguez
- Centro de Investigación en BiotecnologíaUniversidad Autónoma del Estado de Morelos Cuernavaca Mexico
| | | | - Elba Villegas
- Centro de Investigación en BiotecnologíaUniversidad Autónoma del Estado de Morelos Cuernavaca Mexico
| | - Bruno Rivas‐Santiago
- Medical Research Unit‐ZacatecasMexican Institute of Social Security IMSS Zacatecas Mexico
| | - Jessica Villegas‐Moreno
- Centro de Investigaciones QuímicasUniversidad Autónoma del Estado de Morelos Cuernavaca Mexico
| | - Carlos Amero
- Centro de Investigaciones QuímicasUniversidad Autónoma del Estado de Morelos Cuernavaca Mexico
| | - Raymond S. Norton
- Monash Institute of Pharmaceutical SciencesMonash University Parkville Victoria Australia
| | - Gerardo Corzo
- Instituto de BiotecnologíaUniversidad Nacional Autónoma de México Cuernavaca Mexico
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Drake KK, Aiello CM, Bowen L, Lewison RL, Esque TC, Nussear KE, Waters SC, Hudson PJ. Complex immune responses and molecular reactions to pathogens and disease in a desert reptile ( Gopherus agassizii). Ecol Evol 2019; 9:2516-2534. [PMID: 30891197 PMCID: PMC6405529 DOI: 10.1002/ece3.4897] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/12/2018] [Accepted: 11/29/2018] [Indexed: 12/16/2022] Open
Abstract
Immune function plays an important role in an animal's defense against infectious disease. In reptiles, immune responses may be complex and counterintuitive, and diagnostic tools used to identify infection, such as induced antibody responses are limited. Recent studies using gene transcription profiling in tortoises have proven useful in identifying immune responses to various intrinsic and extrinsic stressors. As part of a larger experiment with Mojave desert tortoises (Gopherus agassizii), we facilitated the transmission of the pathogenic bacteria, Mycoplasma agassizii (Myag), to naïve adults and measured innate and induced immune reactions over time. Specifically, we evaluated clinical condition, presence of Myag in the nasal/oral cavity, induced antibody responses specific to Myag, and measured molecular reactions (gene transcript profiles) in 15 captive tortoises classified as naïve, exposed, or infected and 14 wild tortoises for comparison. Myag was confirmed inside the nasal/oral cavity in exposed tortoises within 30-60 days of introduction to infected animals, yet we did not detect Myag specific induced antibody responses in these individuals until 420-595 days post exposure. Surprisingly, we found no overall differences in the gene transcript profiles between our experimental treatment groups throughout this study. This work highlights the complexities in assessing immune function and diagnosing pathogen related infections in tortoises and other reptiles.
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Affiliation(s)
- K. Kristina Drake
- Western Ecological Research CenterU.S. Geological SurveyHendersonNevada
- Department of BiologySan Diego State UniversitySan DiegoCalifornia
- Graduate Group in EcologyUniversity of California‐DavisDavisCalifornia
| | - Christina M. Aiello
- Western Ecological Research CenterU.S. Geological SurveyHendersonNevada
- Department of BiologyPennsylvania State UniversityUniversity ParkPennsylvania
| | - Lizabeth Bowen
- Western Ecological Research CenterU.S. Geological SurveyDavisCalifornia
| | | | - Todd C. Esque
- Western Ecological Research CenterU.S. Geological SurveyHendersonNevada
| | | | - Shannon C. Waters
- Western Ecological Research CenterU.S. Geological SurveyDavisCalifornia
| | - Peter J. Hudson
- Department of BiologyPennsylvania State UniversityUniversity ParkPennsylvania
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15
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Genome-wide analysis of the ovodefensin gene family: Monophyletic origin, independent gene duplication and presence of different selection patterns. INFECTION GENETICS AND EVOLUTION 2019; 68:265-272. [DOI: 10.1016/j.meegid.2019.01.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 11/28/2018] [Accepted: 01/02/2019] [Indexed: 11/15/2022]
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16
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Wirth W, Schwarzkopf L, Skerratt LF, Ariel E. Ranaviruses and reptiles. PeerJ 2018; 6:e6083. [PMID: 30581674 PMCID: PMC6295156 DOI: 10.7717/peerj.6083] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 11/06/2018] [Indexed: 01/22/2023] Open
Abstract
Ranaviruses can infect many vertebrate classes including fish, amphibians and reptiles, but for the most part, research has been focused on non-reptilian hosts, amphibians in particular. More recently, reports of ranaviral infections of reptiles are increasing with over 12 families of reptiles currently susceptible to ranaviral infection. Reptiles are infected by ranaviruses that are genetically similar to, or the same as, the viruses that infect amphibians and fish; however, physiological and ecological differences result in differences in study designs. Although ranaviral disease in reptiles is often influenced by host species, viral strain and environmental differences, general trends in pathogenesis are emerging. More experimental studies using a variety of reptile species, life stages and routes of transmission are required to unravel the complexity of wild ranavirus transmission. Further, our understanding of the reptilian immune response to ranaviral infection is still lacking, although the considerable amount of work conducted in amphibians will serve as a useful guide for future studies in reptiles.
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Affiliation(s)
- Wytamma Wirth
- College of Public Health, Medical and Veterinary Sciences, James Cook University of North Queensland, Townsville, QLD, Australia
| | - Lin Schwarzkopf
- College of Science and Engineering, James Cook University of North Queensland, Townsville, QLD, Australia
| | - Lee F Skerratt
- Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Melbourne, Australia
| | - Ellen Ariel
- College of Public Health, Medical and Veterinary Sciences, James Cook University of North Queensland, Townsville, QLD, Australia
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17
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Yu LT, Xiao YP, Li JJ, Ran JS, Yin LQ, Liu YP, Zhang L. Molecular characterization of a novel ovodefensin gene in chickens. Gene 2018; 678:233-240. [PMID: 30098427 DOI: 10.1016/j.gene.2018.08.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/28/2018] [Accepted: 08/06/2018] [Indexed: 01/05/2023]
Abstract
Host defense peptides (HDPs) represent a large group of diverse small peptides that play important roles in host defense and disease resistance. In vertebrates, one of the main types of HDPs belong to defensins, which are less than 100 amino acid residues and characterized by a highly conserved motif of cysteine residues. Recently, a subfamily of defensins, namely ovodefensins (OvoDs), has been identified in birds and reptiles. However, both their family members and evolutionary relationships remain unclear. In the present study, we cloned and characterized a novel gene namely OvoDBβ in chickens. Our results showed that the full length of chicken OvoDBβ mRNA contains 344 bp nucleotides and encodes a 61-amino acid protein. We further revealed that the mRNA of OvoDBβ is abundant in the oviduct of laying hens but absent in many other tissues. Additionally, sequences comparison and analyses suggested that OvoDBβ is orthologous to the gene previously known as zebra finch OvoDB1, albeit it might exhibit specific structures. Furthermore, both OvoDBα and OvoDBβ were existent in the genome of each bird, implying that two types of OvoDBs sharing same cysteine motif have already emerged before the species divergence. More importantly, recombinant OvoDBβ mature peptide exerted antibacterial activity against Escherischia coli (CICC23657 strain) in vitro. These results collectively indicated that the putative sequence, namely chicken OvoDBβ, is a function gene with potential antimicrobial property. Discovery and function characterization of novel HDP genes may help us develop novel antimicrobial agents in the future.
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Affiliation(s)
- Lin-Tian Yu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu Campus, Chengdu 611130, Sichuan, China; Guangxi Agricultural Vocational College, Nanning 530007, Guangxi, China
| | - Ying-Ping Xiao
- Institute of Quality and Standards for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, Zhejiang, China
| | - Jing-Jing Li
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu Campus, Chengdu 611130, Sichuan, China
| | - Jin-Shan Ran
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu Campus, Chengdu 611130, Sichuan, China
| | - Ling-Qian Yin
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu Campus, Chengdu 611130, Sichuan, China
| | - Yi-Ping Liu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu Campus, Chengdu 611130, Sichuan, China.
| | - Long Zhang
- Institute of Ecology, China West Normal University, Nanchong 637009, Sichuan, China.
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18
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Abstract
Discovering new therapeutics for human viral diseases is important for combatting emerging infectious viruses and omnipresent circulating viruses as well as those that can become resistant to the drugs we currently have available. The innate host defense peptide (HDP) repertoire present in animals is a wealth of potential antimicrobial agents that could be mined to meet these needs. While much of the body of research regarding HDPs is in the context of bacteria, there is increasing evidence that they can be an effective source for antivirals. Peptides can be identified in a number of ways, including eco-conservation-minded approaches. Those shown to have antiviral properties can be modified to exhibit desired properties as the relationship between structure and function is elucidated and then developed into therapeutics for human use. This review looks at the discovery and therapeutic potential of HDPs for human viral infections.
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19
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Ageitos J, Sánchez-Pérez A, Calo-Mata P, Villa T. Antimicrobial peptides (AMPs): Ancient compounds that represent novel weapons in the fight against bacteria. Biochem Pharmacol 2017; 133:117-138. [DOI: 10.1016/j.bcp.2016.09.018] [Citation(s) in RCA: 328] [Impact Index Per Article: 46.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 09/19/2016] [Indexed: 01/01/2023]
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20
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Villa TG, Feijoo-Siota L, Rama JLR, Ageitos JM. Antivirals against animal viruses. Biochem Pharmacol 2017; 133:97-116. [PMID: 27697545 PMCID: PMC7092833 DOI: 10.1016/j.bcp.2016.09.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 09/29/2016] [Indexed: 01/19/2023]
Abstract
Antivirals are compounds used since the 1960s that can interfere with viral development. Some of these antivirals can be isolated from a variety of sources, such as animals, plants, bacteria or fungi, while others must be obtained by chemical synthesis, either designed or random. Antivirals display a variety of mechanisms of action, and while some of them enhance the animal immune system, others block a specific enzyme or a particular step in the viral replication cycle. As viruses are mandatory intracellular parasites that use the host's cellular machinery to survive and multiply, it is essential that antivirals do not harm the host. In addition, viruses are continually developing new antiviral resistant strains, due to their high mutation rate, which makes it mandatory to continually search for, or develop, new antiviral compounds. This review describes natural and synthetic antivirals in chronological order, with an emphasis on natural compounds, even when their mechanisms of action are not completely understood, that could serve as the basis for future development of novel and/or complementary antiviral treatments.
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Affiliation(s)
- T G Villa
- Department of Microbiology, Biotechnology Unit, Faculty of Pharmacy, University of Santiago de Compostela 15706, Spain
| | - L Feijoo-Siota
- Department of Microbiology, Biotechnology Unit, Faculty of Pharmacy, University of Santiago de Compostela 15706, Spain
| | - J L R Rama
- Department of Microbiology, Biotechnology Unit, Faculty of Pharmacy, University of Santiago de Compostela 15706, Spain
| | - J M Ageitos
- Department of Microbiology, Biotechnology Unit, Faculty of Pharmacy, University of Santiago de Compostela 15706, Spain.
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21
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Solstad RG, Li C, Isaksson J, Johansen J, Svenson J, Stensvåg K, Haug T. Novel Antimicrobial Peptides EeCentrocins 1, 2 and EeStrongylocin 2 from the Edible Sea Urchin Echinus esculentus Have 6-Br-Trp Post-Translational Modifications. PLoS One 2016; 11:e0151820. [PMID: 27007817 PMCID: PMC4805251 DOI: 10.1371/journal.pone.0151820] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 03/06/2016] [Indexed: 12/18/2022] Open
Abstract
The global problem of microbial resistance to antibiotics has resulted in an urgent need to develop new antimicrobial agents. Natural antimicrobial peptides are considered promising candidates for drug development. Echinoderms, which rely on innate immunity factors in the defence against harmful microorganisms, are sources of novel antimicrobial peptides. This study aimed to isolate and characterise antimicrobial peptides from the Edible sea urchin Echinus esculentus. Using bioassay-guided purification and cDNA cloning, three antimicrobial peptides were characterised from the haemocytes of the sea urchin; two heterodimeric peptides and a cysteine-rich peptide. The peptides were named EeCentrocin 1 and 2 and EeStrongylocin 2, respectively, due to their apparent homology to the published centrocins and strongylocins isolated from the green sea urchin Strongylocentrotus droebachiensis. The two centrocin-like peptides EeCentrocin 1 and 2 are intramolecularly connected via a disulphide bond to form a heterodimeric structure, containing a cationic heavy chain of 30 and 32 amino acids and a light chain of 13 amino acids. Additionally, the light chain of EeCentrocin 2 seems to be N-terminally blocked by a pyroglutamic acid residue. The heavy chains of EeCentrocins 1 and 2 were synthesised and shown to be responsible for the antimicrobial activity of the natural peptides. EeStrongylocin 2 contains 6 cysteines engaged in 3 disulphide bonds. A fourth peptide (Ee4635) was also discovered but not fully characterised. Using mass spectrometric and NMR analyses, EeCentrocins 1 and 2, EeStrongylocin 2 and Ee4635 were all shown to contain post-translationally brominated Trp residues in the 6 position of the indole ring.
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Affiliation(s)
- Runar Gjerp Solstad
- The Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Chun Li
- The Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Johan Isaksson
- Department of Chemistry, the Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Jostein Johansen
- Department of Chemistry, the Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Johan Svenson
- Department of Chemistry, the Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Klara Stensvåg
- The Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Tor Haug
- The Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
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22
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Whenham N, Lu TC, Maidin MB, Wilson PW, Bain MM, Stevenson ML, Stevens MP, Bedford MR, Dunn IC. Ovodefensins, an Oviduct-Specific Antimicrobial Gene Family, Have Evolved in Birds and Reptiles to Protect the Egg by Both Sequence and Intra-Six-Cysteine Sequence Motif Spacing1. Biol Reprod 2015; 92:154. [DOI: 10.1095/biolreprod.114.126839] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 04/09/2015] [Indexed: 11/01/2022] Open
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23
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Conlon JM. Host-defense peptides of the skin with therapeutic potential: From hagfish to human. Peptides 2015; 67:29-38. [PMID: 25794853 DOI: 10.1016/j.peptides.2015.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/08/2015] [Accepted: 03/09/2015] [Indexed: 12/21/2022]
Abstract
It is now well established that peptides that were first identified on the basis of their ability to inhibit growth of bacteria and fungi are multifunctional and so are more informatively described as host-defense peptides. In some cases, their role in protecting the organism against pathogenic microorganisms, although of importance, may be secondary. A previous article in the journal (Peptides 2014; 57:67-77) assessed the potential of peptides present in the skin secretions of frogs for development into anticancer, antiviral, immunomodulatory and antidiabetic drugs. This review aims to extend the scope of this earlier article by focusing upon therapeutic applications of host-defense peptides present in skin secretions and/or skin extracts of species belonging to other vertebrate classes (Agnatha, Elasmobranchii, Teleostei, Reptilia, and Mammalia as represented by the human) that supplement their potential role as anti-infectives for use against multidrug-resistant microorganisms.
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Affiliation(s)
- J Michael Conlon
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine BT52 1SA, UK.
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24
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Antibacterial products of marine organisms. Appl Microbiol Biotechnol 2015; 99:4145-73. [PMID: 25874533 DOI: 10.1007/s00253-015-6553-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 03/17/2015] [Accepted: 03/19/2015] [Indexed: 10/23/2022]
Abstract
Marine organisms comprising microbes, plants, invertebrates, and vertebrates elaborate an impressive array of structurally diverse antimicrobial products ranging from small cyclic compounds to macromolecules such as proteins. Some of these biomolecules originate directly from marine animals while others arise from microbes associated with the animals. It is noteworthy that some of the biomolecules referred to above are structurally unique while others belong to known classes of compounds, peptides, and proteins. Some of the antibacterial agents are more active against Gram-positive bacteria while others have higher effectiveness on Gram-negative bacteria. Some are efficacious against both Gram-positive and Gram-negative bacteria and against drug-resistant strains as well. The mechanism of antibacterial action of a large number of the chemically identified antibacterial agents, possible synergism with currently used antibiotics, and the issue of possible toxicity on mammalian cells and tissues await elucidation. The structural characteristics pivotal to antibacterial activity have been ascertained in only a few studies. Demonstration of efficacy of the antibacterial agents in animal models of bacterial infection is highly desirable. Structural characterization of the active principles present in aqueous and organic extracts of marine organisms with reportedly antibacterial activity would be desirable.
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25
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Antimicrobial peptides in reptiles. Pharmaceuticals (Basel) 2014; 7:723-53. [PMID: 24918867 PMCID: PMC4078517 DOI: 10.3390/ph7060723] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/09/2014] [Accepted: 05/12/2014] [Indexed: 12/17/2022] Open
Abstract
Reptiles are among the oldest known amniotes and are highly diverse in their morphology and ecological niches. These animals have an evolutionarily ancient innate-immune system that is of great interest to scientists trying to identify new and useful antimicrobial peptides. Significant work in the last decade in the fields of biochemistry, proteomics and genomics has begun to reveal the complexity of reptilian antimicrobial peptides. Here, the current knowledge about antimicrobial peptides in reptiles is reviewed, with specific examples in each of the four orders: Testudines (turtles and tortosises), Sphenodontia (tuataras), Squamata (snakes and lizards), and Crocodilia (crocodilans). Examples are presented of the major classes of antimicrobial peptides expressed by reptiles including defensins, cathelicidins, liver-expressed peptides (hepcidin and LEAP-2), lysozyme, crotamine, and others. Some of these peptides have been identified and tested for their antibacterial or antiviral activity; others are only predicted as possible genes from genomic sequencing. Bioinformatic analysis of the reptile genomes is presented, revealing many predicted candidate antimicrobial peptides genes across this diverse class. The study of how these ancient creatures use antimicrobial peptides within their innate immune systems may reveal new understandings of our mammalian innate immune system and may also provide new and powerful antimicrobial peptides as scaffolds for potential therapeutic development.
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26
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In addition to its antiviral and immunomodulatory properties, the zebrafish β-defensin 2 (zfBD2) is a potent viral DNA vaccine molecular adjuvant. Antiviral Res 2014; 101:136-47. [DOI: 10.1016/j.antiviral.2013.11.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 11/04/2013] [Accepted: 11/18/2013] [Indexed: 11/21/2022]
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27
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Alibardi L. Ultrastructural immunolocalization of beta-defensin-27 in granulocytes of the dermis and wound epidermis of lizard suggests they contribute to the anti-microbial skin barrier. Anat Cell Biol 2013; 46:246-53. [PMID: 24386597 PMCID: PMC3875842 DOI: 10.5115/acb.2013.46.4.246] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 09/05/2012] [Accepted: 09/27/2012] [Indexed: 11/27/2022] Open
Abstract
The high resistance to infections in lizard wounds suggests that these reptiles possess effective antimicrobial peptides in their tissues. The present immunocytochemical study shows the cellular localization of beta-defensin 27 in tail tissues and in the blood, a defensin previously identified in the lizard Anolis carolinensis through biomolecular methods. Beta-defensin-27 immunoreactivity is only observed in some large granules mainly contained in heterophilic granulocytes that are sparse within the dermis of the skin or in the isolated blood. This peptide is absent in other cell types of the skin, in keratinocytes and in subdermal muscle tissue of the tail in normal conditions. Pre-corneous keratinocytes of the regenerating tail epidermis are unlabeled or show a weak labeling for the peptide only in sparse cytoplasmic areas or in the extracellular spaces among corneocytes of the wound and regenerating epidermis. The study suggests that beta-defensin 27 is normally stored in granulocytes present in the blood or in connective tissues while in the epidermis keratinocytes do not show the presence of this peptide unless these cells are stimulated from injury to produce and likely release beta-defensins.
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28
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Immunolocalization of a beta-defensin (Tu-BD-1) in the skin and subdermal granulocytes of turtles indicate the presence of an antimicrobial skin barrier. Ann Anat 2013; 195:554-61. [DOI: 10.1016/j.aanat.2013.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 06/27/2013] [Accepted: 07/17/2013] [Indexed: 12/16/2022]
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29
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Hilchie AL, Vale R, Zemlak TS, Hoskin DW. Generation of a hematologic malignancy-selective membranolytic peptide from the antimicrobial core (RRWQWR) of bovine lactoferricin. Exp Mol Pathol 2013; 95:192-8. [PMID: 23892223 DOI: 10.1016/j.yexmp.2013.07.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 07/17/2013] [Indexed: 11/17/2022]
Abstract
Cationic antimicrobial peptides such as bovine lactoferricin (LfcinB) constitute an important innate defense mechanism against many microbial pathogens. LfcinB also binds to and selectively kills human cancer cells via a mechanism that involves reactive oxygen species (ROS) generation and caspase activation. The antimicrobial core of LfcinB consists of only six amino acids (RRWQWR), referred to in this study as LfcinB6. Although free LfcinB6 is devoid of cytotoxic activity against cancer cells, we show here that adding a cell-penetrating hepta-arginine sequence via a glycine-glycine linker to LfcinB6 generates a peptide (MPLfcinB6) that is selectively cytotoxic for human T-leukemia and B-lymphoma cells. Flow cytometric analysis of propidium iodide and fluorescein isothiocyanate-dextran uptake by MPLfcinB6-treated cancer cells revealed extensive damage to the cell membrane, which was confirmed by scanning electron microscopy. MPLfcinB6-induced cytotoxicity was also associated with sequential ROS production and mitochondrial membrane permeabilization; however, neither ROS nor caspase activation caused by the loss of mitochondrial membrane integrity was essential for peptide-mediated cell death. We conclude that MPLfcinB6 selectively kills human T-leukemia and B-lymphoma cells by causing extensive and irreparable damage to the cell membrane.
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Affiliation(s)
- Ashley L Hilchie
- Department of Microbiology & Immunology, Dalhousie University, P.O. Box 15000, Halifax, Nova Scotia, B3H 4R2, Canada
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30
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BENATO F, DALLA VALLE L, SKOBO T, ALIBARDI L. Biomolecular Identification of Beta-Defensin-Like Peptides From the Skin of the Soft-Shelled TurtleApalone spinifera. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2013; 320:210-7. [DOI: 10.1002/jez.b.22495] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 02/07/2013] [Accepted: 02/09/2013] [Indexed: 12/22/2022]
Affiliation(s)
- F. BENATO
- Department of Biology; University of Padova; Padova; Italy
| | - L. DALLA VALLE
- Department of Biology; University of Padova; Padova; Italy
| | - T. SKOBO
- Department of Biology; University of Padova; Padova; Italy
| | - L. ALIBARDI
- Comparative Histolab and Department of Biology; University of Bologna; Bologna; Italy
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31
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Development of a novel multiplex lateral flow assay using an antimicrobial peptide for the detection of Shiga toxin-producing Escherichia coli. J Microbiol Methods 2013; 93:251-6. [PMID: 23523969 DOI: 10.1016/j.mimet.2013.03.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 03/01/2013] [Accepted: 03/11/2013] [Indexed: 11/22/2022]
Abstract
The binding capacity of peptides with broad antimicrobial activity, or antimicrobial peptides (AMPs), to microbes has recently been applied to the specific detection of bacteria and viruses. We established a novel lateral flow assay (LFA) that combines AMPs labeled with colloidal gold and a target-specific antibody immobilized on a nitrocellulose membrane. α-Helical AMPs, especially cecropin P1 (CP1), magainin 2 (MG2), and ceratotoxin A (CtxA), were shown to have optimal properties as probes in LFA. We also established a multiplex LFA for the simultaneous detection and identification of three serogroups of Shiga toxin-producing Escherichia coli (STEC) using the CP1 probe with polyclonal antibodies anti-O157, anti-O26, and anti-O111. Each serogroup of E. coli could easily and rapidly be detected by multiplex LFA using CP1 and each was clearly visualized in a different position on the LFA strip. The multiplex LFA could detect all tested E. coli strains from serogroups O157 (22/22), O26 (17/17), and O111 (7/7), and the detection limit was 10(4)CFU/mL. No other serogroups of E. coli, including STEC O45, O91, O103, O121, and O145, or non-E. coli strains, reacted. The multiplex LFA could detect E. coli O157, O26, and O111 in food samples at very low levels (6.3, 2.9, and 5.6 CFU per 25 g of ground beef, respectively) after 18-h enrichment, and these results were in accordance with the results of the culture method, immunochromatography (IC) strip, and PCR. Given the broad binding capacity, AMP probes in combination with specific antibodies in the novel multiplex LFA may have the potential to detect various microbes simultaneously with identification on a single strip.
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Dalla Valle L, Benato F, Maistro S, Quinzani S, Alibardi L. Bioinformatic and molecular characterization of beta-defensins-like peptides isolated from the green lizard Anolis carolinensis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 36:222-229. [PMID: 21663758 DOI: 10.1016/j.dci.2011.05.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 05/24/2011] [Accepted: 05/24/2011] [Indexed: 05/30/2023]
Abstract
The high resistance of lizards to infections indicates that anti-microbial peptides may be involved. Through the analysis of the green lizard (Anolis carolinensis) genome and the expressed sequence tag (EST) libraries 32 beta-defensin-like-peptides have been identified. The level of expression of some of these genes in different tissues has been determined by semi-quantitative RT-PCR. Gene expression and structure analysis suggest the presence of alternative splicing mechanisms, with a number of exons ranging from two to four, similar to that for beta-defensins genes in mammals. Lizard beta-defensin-like peptides present the characteristic cysteine-motif identified in mammalian and avian beta-defensins. Phylogenetic analysis indicates that some lizard beta-defensins-like peptides are related to crotamine and crotamin-like peptides of snakes and lizards suggesting that beta-defensins and venomous peptides have a common ancestor gene.
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Affiliation(s)
- Luisa Dalla Valle
- Department of Biology, via U. Bassi 58/B, University of Padova, 25131 Padova, Italy.
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Wang R, Ma D, Lin L, Zhou C, Han Z, Shao Y, Liao W, Liu S. Identification and characterization of an avian β-defensin orthologue, avian β-defensin 9, from quails. Appl Microbiol Biotechnol 2010; 87:1395-405. [DOI: 10.1007/s00253-010-2591-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 03/24/2010] [Accepted: 03/26/2010] [Indexed: 01/01/2023]
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Zimmerman LM, Vogel LA, Bowden RM. Understanding the vertebrate immune system: insights from the reptilian perspective. J Exp Biol 2010; 213:661-71. [DOI: 10.1242/jeb.038315] [Citation(s) in RCA: 285] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Summary
Reptiles are ectothermic amniotes, providing the key link between ectothermic anamniotic fishes and amphibians, and endothermic amniotic birds and mammals. A greater understanding of reptilian immunity will provide important insights into the evolutionary history of vertebrate immunity as well as the growing field of eco-immunology. Like mammals, reptile immunity is complex and involves innate, cell-mediated and humoral compartments but, overall, there is considerably less known about immune function in reptiles. We review the current literature on each branch of the reptilian immune system, placing this information in context to other vertebrates. Further, we identify key areas that are prime for research as well as areas that are lagging because of lack of reagents in non-model systems.
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Affiliation(s)
- L. M. Zimmerman
- School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
| | - L. A. Vogel
- School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
| | - R. M. Bowden
- School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
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Linde A, Wachter B, Höner OP, Dib L, Ross C, Tamayo AR, Blecha F, Melgarejo T. Natural History of Innate Host Defense Peptides. Probiotics Antimicrob Proteins 2009; 1:97-112. [DOI: 10.1007/s12602-009-9031-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Stegemann C, Kolobov A, Leonova YF, Knappe D, Shamova O, Ovchinnikova TV, Kokryakov VN, Hoffmann R. Isolation, purification and de novo sequencing of TBD-1, the first beta-defensin from leukocytes of reptiles. Proteomics 2009; 9:1364-73. [DOI: 10.1002/pmic.200800569] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Nagaraj R. Peptides: Isolation, production, and use in India. Biotechnol J 2009; 4:329-34. [DOI: 10.1002/biot.200800257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Wang Y, Hong J, Liu X, Yang H, Liu R, Wu J, Wang A, Lin D, Lai R. Snake cathelicidin from Bungarus fasciatus is a potent peptide antibiotics. PLoS One 2008; 3:e3217. [PMID: 18795096 PMCID: PMC2528936 DOI: 10.1371/journal.pone.0003217] [Citation(s) in RCA: 178] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Accepted: 08/25/2008] [Indexed: 12/21/2022] Open
Abstract
Background Cathelicidins are a family of antimicrobial peptides acting as multifunctional effector molecules of innate immunity, which are firstly found in mammalians. Recently, several cathelicidins have also been found from chickens and fishes. No cathelicidins from other non-mammalian vertebrates have been reported. Principal Findings In this work, a cathelicidin-like antimicrobial peptide named cathelicidin-BF has been purified from the snake venoms of Bungarus fasciatus and its cDNA sequence was cloned from the cDNA library, which confirm the presence of cathelicidin in reptiles. As other cathelicidins, the precursor of cathelicidin-BF has cathelin-like domain at the N terminus and carry the mature cathelicidin-BF at the C terminus, but it has an atypical acidic fragment insertion between the cathelin-like domain and the C-terminus. The acidic fragment is similar to acidic domains of amphibian antimicrobial precursors. Phylogenetic analysis revealed that the snake cathelicidin had the nearest evolution relationship with platypus cathelicidin. The secondary structure of cathelicidin-BF investigated by CD and NMR spectroscopy in the presence of the helicogenic solvent TFE is an amphipathic α-helical conformation as many other cathelicidins. The antimicrobial activities of cathelicidin BF against forty strains of microorganisms were tested. Cathelicidin-BF efficiently killed bacteria and some fungal species including clinically isolated drug-resistance microorganisms. It was especially active against Gram-negative bacteria. Furthermore, it could exert antimicrobial activity against some saprophytic fungus. No hemolytic and cytotoxic activity was observed at the dose of up to 400 µg/ml. Cathelicidin-BF could exist stably in the mice plasma for at least 2.5 hours. Conclusion Discovery of snake cathelicidin with atypical structural and functional characterization offers new insights on the evolution of cathelicidins. Potent, broad spectrum, salt-independent antimicrobial activities make cathelicidin-BF an excellent candidate for clinical or agricultural antibiotics.
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Affiliation(s)
- Yipeng Wang
- Biotoxin Units of Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Jing Hong
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Xiuhong Liu
- Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Hailong Yang
- Biotoxin Units of Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Rui Liu
- Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Jing Wu
- Biotoxin Units of Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Aili Wang
- Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Donghai Lin
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- * E-mail: (DL); (RL)
| | - Ren Lai
- Biotoxin Units of Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Nanjing, Jiangsu, China
- * E-mail: (DL); (RL)
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Falco A, Chico V, Marroquí L, Perez L, Coll JM, Estepa A. Expression and antiviral activity of a beta-defensin-like peptide identified in the rainbow trout (Oncorhynchus mykiss) EST sequences. Mol Immunol 2007; 45:757-65. [PMID: 17692376 DOI: 10.1016/j.molimm.2007.06.358] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Revised: 06/26/2007] [Accepted: 06/29/2007] [Indexed: 01/13/2023]
Abstract
The in silico identification of a beta-defensin-like peptide sequence (omBD-1) in the rainbow trout (Oncorhynchuss mykiss) database of salmonid EST is reported here. We have studied the transcript expression of this beta-defensin-like sequence in different organs and expressed the recombinant peptide in a fish cell line. Finally, we have demonstrated the in vitro antiviral activity of the recombinant trout beta-defensin-like peptide against viral haemorrhagic septicaemia rhabdovirus (VHSV), one of the most devastating viruses for worldwide aquaculture. Thus, the resistance to VHSV infection of EPC cells transfected with pMCV 1.4-omBD-1 has been shown. Since EPC cells transfected with omBD-1 produced acid and heat stable antiviral activity and up regulation of Mx, a type I IFN-mediated mechanism of antiviral action is suggested. To our knowledge, this is the first report showing biological activity of a beta-defensin-like peptide from any fish.
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Affiliation(s)
- A Falco
- IBMC, Miguel Hernández University, 03202 Elche, Spain
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Abstract
PURPOSE OF REVIEW This review describes recent progress in our understanding of defensins and their contributions to innate immunity. Defensins are small, cysteine-rich endogenous antibiotic peptides. Human neutrophils contain large amounts of three alpha-defensins (HNP-1-HNP-3), and smaller amounts of a fourth, HNP-4. Monocytes and macrophages generally lack defensins, but they release messengers that induce the synthesis of beta-defensins in epithelial cells. RECENT FINDINGS In addition to their antimicrobial and immunomodulatory effects, HNP-1-HNP-3 possess antiviral and toxin-neutralizing properties. Induction of beta-defensins in epithelial cells is mediated by cell-surface Toll-like receptors or cytoplasmic peptidoglycan receptors that can recognize pathogen-associated molecules. Mutations in Nod2, a cytoplasmic peptidoglycan receptor, are associated with reduced levels of intestinal alpha-defensins and ileal Crohn's disease. Human defensin genes show marked copy-number polymorphism. High level constitutive expression of defensins may afford protection against HIV-1 and other defensin-sensitive pathogens. Theta-defensins (cyclic octadecapeptides found in nonhuman primates) have impressive antiviral and antitoxic properties. SUMMARY The multiple properties of defensins contribute to human innate immunity against bacteria, bacterial toxins, and viruses.
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Affiliation(s)
- Robert I Lehrer
- David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA.
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