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Yasmin R, Thakur S, Blotra A, Sahu A, Vasudevan K, Reza MA, Doley R. Proteome analysis of Daboia russelii venom, a medically important snake from the Indian sub-continent. Toxicon 2024; 237:107532. [PMID: 38030094 DOI: 10.1016/j.toxicon.2023.107532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/31/2023] [Accepted: 11/21/2023] [Indexed: 12/01/2023]
Abstract
Daboia russelii is a category-I medically important snake throughout the Indian sub-continent contributing to majority of snakebite incidences in this part of the world. As such, extensive studies on its venom composition and search of efficient and appropriate interventions for its treatment become crucial. In this study, the proteome of Daboia russelii venom from Tanore, Rajshahi, Bangladesh was profiled using a combination of chromatographic and mass spectrometric techniques. A total of 37 different proteins belonging to 11 different snake venom protein families were detected. Proteomics analysis revealed the presence of major phospholipase A2 toxins. Daboiatoxin (both A and B subunits), the main lethal PLA2 toxin in the venom of Daboia siamensis (Myanmar viper) which is neurotoxic, myotoxic and cytotoxic was detected. Presence of Daboxin P, which is a major protein in the venom of Indian Daboia russelii with strong anticoagulant activity, was also observed. Inconsistent distribution of such lethal toxins in the venom of same species calls for more investigations of snake venoms from lesser explored regions and formulation of better alternatives to the current antivenom therapy for efficient treatment.
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Affiliation(s)
- Rafika Yasmin
- Molecular Toxinology Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India
| | - Susmita Thakur
- Molecular Toxinology Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India
| | - Avni Blotra
- Laboratory for the Conservation of Endangered Species, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, 500048, India
| | - Alka Sahu
- Laboratory for the Conservation of Endangered Species, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, 500048, India
| | - Karthikeyan Vasudevan
- Laboratory for the Conservation of Endangered Species, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, 500048, India
| | - Md Abu Reza
- Molecular Biology and Protein Science Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Robin Doley
- Molecular Toxinology Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India.
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2
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Suranse V, Jackson TNW, Sunagar K. Contextual Constraints: Dynamic Evolution of Snake Venom Phospholipase A 2. Toxins (Basel) 2022; 14:toxins14060420. [PMID: 35737081 PMCID: PMC9231074 DOI: 10.3390/toxins14060420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 11/25/2022] Open
Abstract
Venom is a dynamic trait that has contributed to the success of numerous organismal lineages. Predominantly composed of proteins, these complex cocktails are deployed for predation and/or self-defence. Many non-toxic physiological proteins have been convergently and recurrently recruited by venomous animals into their toxin arsenal. Phospholipase A2 (PLA2) is one such protein and features in the venoms of many organisms across the animal kingdom, including snakes of the families Elapidae and Viperidae. Understanding the evolutionary history of this superfamily would therefore provide insight into the origin and diversification of venom toxins and the evolution of novelty more broadly. The literature is replete with studies that have identified diversifying selection as the sole influence on PLA2 evolution. However, these studies have largely neglected the structural/functional constraints on PLA2s, and the ecology and evolutionary histories of the diverse snake lineages that produce them. By considering these crucial factors and employing evolutionary analyses integrated with a schema for the classification of PLA2s, we uncovered lineage-specific differences in selection regimes. Thus, our work provides novel insights into the evolution of this major snake venom toxin superfamily and underscores the importance of considering the influence of evolutionary and ecological contexts on molecular evolution.
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Affiliation(s)
- Vivek Suranse
- Evolutionary Venomics Laboratory, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India;
| | - Timothy N. W. Jackson
- Australian Venom Research Unit, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, VIC 3010, Australia;
| | - Kartik Sunagar
- Evolutionary Venomics Laboratory, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India;
- Correspondence: ; Tel.: +91-080-2293-2895
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3
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Teixeira SC, Borges BC, Oliveira VQ, Carregosa LS, Bastos LA, Santos IA, Jardim ACG, Melo FF, Freitas LM, Rodrigues VM, Lopes DS. Insights into the antiviral activity of phospholipases A 2 (PLA 2s) from snake venoms. Int J Biol Macromol 2020; 164:616-625. [PMID: 32698062 PMCID: PMC7368918 DOI: 10.1016/j.ijbiomac.2020.07.178] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/08/2020] [Accepted: 07/14/2020] [Indexed: 12/18/2022]
Abstract
Viruses are associated with several human diseases that infect a large number of individuals, hence directly affecting global health and economy. Owing to the lack of efficient vaccines, antiviral therapy and emerging resistance strains, many viruses are considered as a potential threat to public health. Therefore, researches have been developed to identify new drug candidates for future treatments. Among them, antiviral research based on natural molecules is a promising approach. Phospholipases A2 (PLA2s) isolated from snake venom have shown significant antiviral activity against some viruses such as Dengue virus, Human Immunodeficiency virus, Hepatitis C virus and Yellow fever virus, and have emerged as an attractive alternative strategy for the development of novel antiviral therapy. Thus, this review provides an overview of remarkable findings involving PLA2s from snake venom that possess antiviral activity, and discusses the mechanisms of action mediated by PLA2s against different stages of virus replication cycle. Additionally, molecular docking simulations were performed by interacting between phospholipids from Dengue virus envelope and PLA2s from Bothrops asper snake venom. Studies on snake venom PLA2s highlight the potential use of these proteins for the development of broad-spectrum antiviral drugs.
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Affiliation(s)
- S C Teixeira
- Department of Immunology, Institute of Biomedical Science, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - B C Borges
- Department of Immunology, Institute of Biomedical Science, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - V Q Oliveira
- Multidisciplinary Institute of Health, Anísio Teixeira Campus, Federal University of Bahia, Vitória da Conquista, BA, Brazil
| | - L S Carregosa
- Multidisciplinary Institute of Health, Anísio Teixeira Campus, Federal University of Bahia, Vitória da Conquista, BA, Brazil
| | - L A Bastos
- Multidisciplinary Institute of Health, Anísio Teixeira Campus, Federal University of Bahia, Vitória da Conquista, BA, Brazil
| | - I A Santos
- Laboratory of Virology, Institute of Biomedical Science, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - A C G Jardim
- Laboratory of Virology, Institute of Biomedical Science, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | - F F Melo
- Multidisciplinary Institute of Health, Anísio Teixeira Campus, Federal University of Bahia, Vitória da Conquista, BA, Brazil
| | - L M Freitas
- Multidisciplinary Institute of Health, Anísio Teixeira Campus, Federal University of Bahia, Vitória da Conquista, BA, Brazil
| | - V M Rodrigues
- Laboratory of Biochemistry and Animal Toxins, Institute of Biotechnology, Federal University of Uberlândia, Uberlândia, MG, Brazil.
| | - D S Lopes
- Multidisciplinary Institute of Health, Anísio Teixeira Campus, Federal University of Bahia, Vitória da Conquista, BA, Brazil; Institute of Health Sciences, Department of Bio-Function, Federal University of Bahia, Salvador, BA, Brazil.
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4
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Patra A, Kalita B, Chanda A, Mukherjee AK. Proteomics and antivenomics of Echis carinatus carinatus venom: Correlation with pharmacological properties and pathophysiology of envenomation. Sci Rep 2017; 7:17119. [PMID: 29215036 PMCID: PMC5719401 DOI: 10.1038/s41598-017-17227-y] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 10/30/2017] [Indexed: 01/12/2023] Open
Abstract
The proteome composition of Echis carinatus carinatus venom (ECV) from India was studied for the first time by tandem mass spectrometry analysis. A total of 90, 47, and 22 distinct enzymatic and non-enzymatic proteins belonging to 15, 10, and 6 snake venom protein families were identified in ECV by searching the ESI-LC-MS/MS data against non-redundant protein databases of Viperidae (taxid 8689), Echis (taxid 8699) and Echis carinatus (taxid 40353), respectively. However, analysis of MS/MS data against the Transcriptome Shotgun Assembly sequences (87 entries) of conger E. coloratus identified only 14 proteins in ECV. Snake venom metalloproteases and snaclecs, the most abundant enzymatic and non-enzymatic proteins, respectively in ECV account for defibrinogenation and the strong in vitro pro-coagulant activity. Further, glutaminyl cyclase, aspartic protease, aminopeptidase, phospholipase B, vascular endothelial growth factor, and nerve growth factor were reported for the first time in ECV. The proteome composition of ECV was well correlated with its biochemical and pharmacological properties and clinical manifestations observed in Echis envenomed patients. Neutralization of enzymes and pharmacological properties of ECV, and immuno-cross-reactivity studies unequivocally point to the poor recognition of <20 kDa ECV proteins, such as PLA2, subunits of snaclec, and disintegrin by commercial polyvalent antivenom.
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Affiliation(s)
- Aparup Patra
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, 784028, Assam, India
| | - Bhargab Kalita
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, 784028, Assam, India
| | - Abhishek Chanda
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, 784028, Assam, India
| | - Ashis K Mukherjee
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, 784028, Assam, India.
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Jia Y, Ermolinsky B, Garza A, Provenzano D. Phospholipase A2 in the venom of three cottonmouth snakes. Toxicon 2017. [DOI: 10.1016/j.toxicon.2017.06.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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6
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de Queiroz MR, de Sousa BB, da Cunha Pereira DF, Mamede CCN, Matias MS, de Morais NCG, de Oliveira Costa J, de Oliveira F. The role of platelets in hemostasis and the effects of snake venom toxins on platelet function. Toxicon 2017; 133:33-47. [PMID: 28435120 DOI: 10.1016/j.toxicon.2017.04.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/12/2017] [Accepted: 04/19/2017] [Indexed: 12/09/2022]
Abstract
The human body has a set of physiological processes, known as hemostasis, which keeps the blood fluid and free of clots in normal vessels; in the case of vascular injury, this process induces the local formation of a hemostatic plug, preventing hemorrhage. The hemostatic system in humans presents complex physiological interactions that involve platelets, plasma proteins, endothelial and subendothelial structures. Disequilibrium in the regulatory mechanisms that control the growth and the size of the thrombus is one of the factors that favors the development of diseases related to vascular disorders such as myocardial infarction and stroke, which are among the leading causes of death in the western world. Interfering with platelet function is a strategy for the treatment of thrombotic diseases. Antiplatelet drugs are used mainly in cases related to arterial thrombosis and interfere in the formation of the platelet plug by different mechanisms. Aspirin (acetylsalicylic acid) is the oldest and most widely used antithrombotic drug. Although highly effective in most cases, aspirin has limitations compared to other drugs used in the treatment of homeostatic disorders. For this reason, research related to molecules that interfere with platelet aggregation are of great relevance. In this regard, snake venoms are known to contain a number of molecules that interfere with hemostasis, including platelet function. The mechanisms by which snake venom components inhibit or activate platelet aggregation are varied and can be used as tools for the diagnosis and the treatment of several hemostatic disorders. The aim of this review is to present the role of platelets in hemostasis and the mechanisms by which snake venom toxins interfere with platelet function.
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Affiliation(s)
- Mayara Ribeiro de Queiroz
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil
| | - Bruna Barbosa de Sousa
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil
| | | | - Carla Cristine Neves Mamede
- Instituto de Ciências Agrárias, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil
| | - Mariana Santos Matias
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | | | - Júnia de Oliveira Costa
- Instituto Federal de Educação, Ciência e Tecnologia do Triângulo Mineiro, Ituiutaba, MG, Brazil
| | - Fábio de Oliveira
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil.
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7
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Santos-Filho NA, Santos CT. Alpha-type phospholipase A 2 inhibitors from snake blood. J Venom Anim Toxins Incl Trop Dis 2017; 23:19. [PMID: 28344595 PMCID: PMC5364564 DOI: 10.1186/s40409-017-0110-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 03/16/2017] [Indexed: 01/22/2023] Open
Abstract
It is of popular and scientific knowledge that toxins from snake venom (among them the PLA2 and myotoxins) are neutralized by various compounds, such as antibodies and proteins purified from animal blood. Venomous and nonvenomous snakes have PLA2 inhibitory proteins, called PLIs, in their blood serum. One hypothesis that could explain the presence of these PLIs in the serum of venomous snakes would be self-protection against the enzymes of their own venom, which eventually could reach the circulatory system. However, the presence of PLIs in non-venomous snakes suggests that their physiological role might not be restricted to protection against PLA2 toxins, but could be extended to other functions, as in the innate immune system and local regulation of PLA2s. The present study aimed to review the currently available literature on PLA2 and myotoxin alpha inhibitors present in snake plasma, thus helping to improve the research on these molecules. Furthermore, this review includes current information regarding the mechanism of action of these inhibitors in an attempt to better understand their application, and proposes the use of these molecules as new models in snakebite therapy. These molecules may help in the neutralization of different types of phospholipases A2 and myotoxins, complementing the conventional serum therapy.
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Affiliation(s)
- Norival A. Santos-Filho
- Institute of Chemistry, São Paulo State University (UNESP – Univ Estadual Paulista), Araraquara, SP Brazil
| | - Claudia T. Santos
- School of Pharmaceutical Sciences, São Paulo State University (UNESP – Univ Estadual Paulista), Araraquara, SP Brazil
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8
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Molecular characterization of Lys49 and Asp49 phospholipases A₂from snake venom and their antiviral activities against Dengue virus. Toxins (Basel) 2013; 5:1780-98. [PMID: 24131891 PMCID: PMC3813911 DOI: 10.3390/toxins5101780] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/11/2013] [Accepted: 09/26/2013] [Indexed: 01/24/2023] Open
Abstract
We report the detailed molecular characterization of two PLA2s, Lys49 and Asp49 isolated from Bothrops leucurus venom, and examined their effects against Dengue virus (DENV). The Bl-PLA2s, named BlK-PLA2 and BlD-PLA2, are composed of 121 and 122 amino acids determined by automated sequencing of the native proteins and peptides produced by digestion with trypsin. They contain fourteen cysteines with pIs of 9.05 and 8.18 for BlK- and BlD-PLA2s, and show a high degree of sequence similarity to homologous snake venom PLA2s, but may display different biological effects. Molecular masses of 13,689.220 (Lys49) and 13,978.386 (Asp49) were determined by mass spectrometry. DENV causes a prevalent arboviral disease in humans, and no clinically approved antiviral therapy is currently available to treat DENV infections. The maximum non-toxic concentration of the proteins to LLC-MK2 cells determined by MTT assay was 40 µg/mL for Bl-PLA2s (pool) and 20 µg/mL for each isoform. Antiviral effects of Bl-PLA2s were assessed by quantitative Real-Time PCR. Bl-PLA2s were able to reduce DENV-1, DENV-2, and DENV-3 serotypes in LLC-MK2 cells infection. Our data provide further insight into the structural properties and their antiviral activity against DENV, opening up possibilities for biotechnological applications of these Bl-PLA2s as tools of research.
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9
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Conlon JM, Attoub S, Arafat H, Mechkarska M, Casewell NR, Harrison RA, Calvete JJ. Cytotoxic activities of [Ser⁴⁹]phospholipase A₂ from the venom of the saw-scaled vipers Echis ocellatus, Echis pyramidum leakeyi, Echis carinatus sochureki, and Echis coloratus. Toxicon 2013; 71:96-104. [PMID: 23747272 DOI: 10.1016/j.toxicon.2013.05.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Revised: 05/19/2013] [Accepted: 05/23/2013] [Indexed: 11/30/2022]
Abstract
Fractionation by reversed-phase HPLC of venom from four species of saw-scaled viper: Echis ocellatus, Echis pyramidum leakeyi, Echis carinatus sochureki, and Echis coloratus led to identification in each sample of an abundant protein with cytotoxic activity against human non-small cell lung adenocarcinoma A549 cells. The active component in each case was identified by MALDI-TOF mass fingerprinting of tryptic digests as [Ser⁴⁹]phospholipase A₂ ([Ser⁴⁹]PLA₂). An isoform of [Ser⁴⁹]PLA₂ containing the single Ala¹⁸→ Val substitution and a partially characterized [Asp⁴⁹]PLA₂ were also present in the E. coloratus venom. LC₅₀ values against A549 cells for the purified [Ser⁴⁹]PLA₂ proteins from the four species are in the range 2.9-8.5 μM. This range is not significantly different from the range of LC₅₀ values against human umbilical vein endothelial HUVEC cells (2.5-12.2 μM) indicating that the [Ser⁴⁹]PLA₂ proteins show no differential anti-tumor activity. The LC₅₀ value for [Ser⁴⁹]PLA₂ from E. ocellatus against human erythrocytes is >100 μM and the MIC values against Escherichia coli and Staphylococcus aureus are >100 μM. It is suggested that the [Ser⁴⁹]PLA₂ proteins play a major role in producing local tissue necrosis and hemorrhage at the site of envenomation.
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Affiliation(s)
- J Michael Conlon
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain 17666, United Arab Emirates.
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10
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Antitumoral potential of Tunisian snake venoms secreted phospholipases A2. BIOMED RESEARCH INTERNATIONAL 2013; 2013:391389. [PMID: 23509718 PMCID: PMC3581298 DOI: 10.1155/2013/391389] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 09/04/2012] [Indexed: 11/17/2022]
Abstract
Phospholipases type A2 (PLA2s) are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2) are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, α5β1 and αv integrins.
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11
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Induction of mast-cell accumulation by promutoxin, an Arg-49 phospholipase A2. BIOMED RESEARCH INTERNATIONAL 2012; 2013:206061. [PMID: 23509689 PMCID: PMC3591241 DOI: 10.1155/2013/206061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 09/11/2012] [Indexed: 11/17/2022]
Abstract
Local inflammation is a prominent characteristic of snakebite wound, and snake-venom phospholipase A2s (PLA2s) are some of the main component that contribute to accumulation of inflammatory cells. However, the action of an R49 PLA2s, promutoxin from Protobothrops mucrosquamatus venom, on mast-cell accumulation has not been previously examined. Using a mouse peritoneal model, we found that promutoxin can induce approximately-6-fold increase in mast-cell accumulation, and the response lasts at least for 16 h. The promutoxin-induced mast cell accumulation was inhibited by cyproheptadine, terfenadine, and Ginkgolide B, indicating that histamine and platelet-activating factor (PAF) is likely to contribute to the mast-cells accumulation. Preinjection of antibodies against adhesion molecules ICAM-1, CD18, CD11a, and L-selectin showed that ICAM-1, and CD18, CD11a are key adhesion molecules of promutoxin-induced mast-cell accumulation. In conclusion, promutoxin can induce accumulation of mast cells, which may contribute to snake-venom wound.
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Georgieva D, Coronado M, Oberthür D, Buck F, Duhalov D, Arni RK, Betzel C. Crystal structure of a dimeric Ser49 PLA2-like myotoxic component of the Vipera ammodytes meridionalis venomics reveals determinants of myotoxicity and membrane damaging activity. MOLECULAR BIOSYSTEMS 2012; 8:1405-11. [DOI: 10.1039/c2mb05490f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Pierce RD, Kim ES, Girton LW, McMurry JL, Francis JW, Albrecht EA. Characterization of crude Echis carinatus venom-induced cytotoxicity in HEK 293T cells. JOURNAL OF VENOM RESEARCH 2011; 2:59-67. [PMID: 22331993 PMCID: PMC3269807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 12/14/2011] [Accepted: 12/21/2011] [Indexed: 11/20/2022]
Abstract
Echis carinatus (saw-scaled viper) produces potent hemorrhagic venom that causes the development of apoptotic and necrotic tissues. In this study, we used polyethyleneimine (PEI) to enhance cellular adherence, and to determine whether the substrate attachment influenced the survival of cells treated with crude E. carinatus venom. Human embryonic kidney (HEK) 293T cells were grown for 18hr in tissue culture plates with or without polyethyleneimine (PEI), and were then stimulated with crude E. carinatus venom for 3 or 12hr. HEK 293T cells grown without PEI displayed a robust oxidative response to corresponding substrate detachment, loss of plasma membrane integrity and decreased cell viability. Cells grown on PEI adsorbed substrates demonstrated prolonged substrate attachment resulting in significantly higher cell viabilities. These observations suggest that the cytotoxicity of crude E. carinatus venom is dependent upon cellular detachment.
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Affiliation(s)
- Rebecca D Pierce
- αDepartment of Biology and Physics, Kennesaw State University, Kennesaw, GA 30144, USA
| | - Ethan S Kim
- αDepartment of Biology and Physics, Kennesaw State University, Kennesaw, GA 30144, USA
| | - Lance W Girton
- αDepartment of Biology and Physics, Kennesaw State University, Kennesaw, GA 30144, USA
| | - Jonathan L McMurry
- βDepartment of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA 300144, USA
| | - Joshua W Francis
- βDepartment of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA 300144, USA
| | - Eric A Albrecht
- αDepartment of Biology and Physics, Kennesaw State University, Kennesaw, GA 30144, USA,*Correspondence to: Eric Albrecht, E-mail: , Tel: +770 4236447, Fax: +770 4236625
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14
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Nunes DCO, Rodrigues RS, Lucena MN, Cologna CT, Oliveira ACS, Hamaguchi A, Homsi-Brandeburgo MI, Arantes EC, Teixeira DNS, Ueira-Vieira C, Rodrigues VM. Isolation and functional characterization of proinflammatory acidic phospholipase A2 from Bothrops leucurus snake venom. Comp Biochem Physiol C Toxicol Pharmacol 2011; 154:226-33. [PMID: 21699995 DOI: 10.1016/j.cbpc.2011.06.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2011] [Revised: 06/06/2011] [Accepted: 06/08/2011] [Indexed: 12/09/2022]
Abstract
In the present study, an acidic PLA(2), designated Bl-PLA(2), was isolated from Bothrops leucurus snake venom through two chromatographic steps: ion-exchange on CM-Sepharose and hydrophobic chromatography on Phenyl-Sepharose. Bl-PLA(2) was homogeneous on SDS-PAGE and when submitted to 2D electrophoresis the molecular mass was 15,000Da and pI was 5.4. Its N-terminal sequence revealed a high homology with other Asp49 acidic PLA(2)s from snake venoms. Its specific activity was 159.9U/mg and the indirect hemolytic activity was also higher than that of the crude venom. Bl-PLA(2) induced low myotoxic and edema activities as compared to those of the crude venom. Moreover, the enzyme was able to induce increments in IL-12p40, TNF-α, IL-1β and IL-6 levels and no variation of IL-8 and IL-10 in human PBMC stimulated in vitro, suggesting that Bl-PLA(2) induces proinflammatory cytokine production by human mononuclear cells. Bothrops leucurus venom is still not extensively explored and knowledge of its components will contribute for a better understanding of its action mechanism.
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Affiliation(s)
- Débora C O Nunes
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, UFU, Uberlândia, MG, Brazil
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Identification and characterization of a phospholipase A2 from the venom of the Saw-scaled viper: Novel bactericidal and membrane damaging activities. Biochimie 2010; 92:1854-66. [DOI: 10.1016/j.biochi.2010.07.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2010] [Accepted: 07/21/2010] [Indexed: 11/20/2022]
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16
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Calvete JJ, Cid P, Sanz L, Segura A, Villalta M, Herrera M, León G, Harrison R, Durfa N, Nasidi A, Theakston RDG, Warrell DA, Gutiérrez JM. Antivenomic assessment of the immunological reactivity of EchiTAb-Plus-ICP, an antivenom for the treatment of snakebite envenoming in sub-Saharan Africa. Am J Trop Med Hyg 2010; 82:1194-201. [PMID: 20519622 DOI: 10.4269/ajtmh.2010.09-0733] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The immunoreactivity of EchiTAb-Plus-ICP, an antivenom developed for the treatment of snakebite envenoming in sub-Saharan Africa, to venoms of seven Echis and Bitis species, was assessed by "antivenomics." This proteomic approach is based on the ability of an antivenom to immunodeplete homologous or heterologous venom proteins. Our results show an extensive cross-reactivity of this antivenom against all Echis and Bitis venoms studied, as revealed by the complete immunodepletion of the majority of venom components, including metalloproteinases, serine proteinases, C-type lectin-like proteins, some phospholipases A(2) and L-amino acid oxidase. However, some phospholipases A(2), disintegrins and proteinase inhibitors were immunodepleted to only a partial extent. These results support the hypothesis that immunizing horses with a mixture of the venoms of Echis ocellatus, Bitis arietans, and Naja nigricollis generates antibodies capable of recognizing the majority of components of medically-relevant homologous and heterologous viperid venoms of the genera Bitis and Echis from sub-Saharan Africa.
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Affiliation(s)
- Juan J Calvete
- Instituto de Biomedicina de Valencia, C.S.I.C., Jaume Roig 11, 46010 Valencia, Spain.
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17
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Understanding the in vitro neuromuscular activity of snake venom Lys49 phospholipase A2 homologues. Toxicon 2010; 55:1-11. [DOI: 10.1016/j.toxicon.2009.10.025] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 07/22/2009] [Accepted: 10/01/2009] [Indexed: 11/24/2022]
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18
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Induction of microvascular leakage and histamine release by promutoxin, an Arg49 phospholipase A2. Toxicon 2009; 55:888-96. [PMID: 20036273 DOI: 10.1016/j.toxicon.2009.12.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2009] [Revised: 12/14/2009] [Accepted: 12/17/2009] [Indexed: 11/22/2022]
Abstract
It has been recognized that phospholipase A(2) (PLA(2)) is a crucial factor of snake venom induced inflammation. Recently, promutoxin, a novel member of minor subgroup of snake venom PLA(2) (R49 PLA(2)) has been characterized in our laboratory, but its roles in induction of inflammation remain uninvestigated. Using highly purified promutoxin, we found this enzymatically inactive PLA(2) provoked a dose-dependent increase in microvascular leakage in the skin of rats. Pretreatment of rats with compound 48/80 diminished promutoxin-induced skin reaction and reduced mast cell numbers in rats. Cyproheptadine, terfenadine, Ginkgolide B and heparin inhibited promutoxin elicited microvascular leakage when they were co-injected with the stimulus to rat skin. Moreover, promutoxin was found to induce histamine release from human colon, lung and tonsil mast cells, and both metabolic inhibitors and pertussis toxin were capable of inhibiting promutoxin elicited histamine release. Provocation of microvascular leakage and mast cell activation by promutoxin suggests further that snake venom induced inflammation is related to mast cell activation and certain anti-inflammatory drugs could be therapeutic effective in treating snake wound.
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19
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Costa Torres AF, Dantas RT, Toyama MH, Diz Filho E, Zara FJ, Rodrigues de Queiroz MG, Pinto Nogueira NA, Rosa de Oliveira M, de Oliveira Toyama D, Monteiro HSA, Martins AMC. Antibacterial and antiparasitic effects of Bothrops marajoensis venom and its fractions: Phospholipase A2 and L-amino acid oxidase. Toxicon 2009; 55:795-804. [PMID: 19944711 DOI: 10.1016/j.toxicon.2009.11.013] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 11/09/2009] [Accepted: 11/12/2009] [Indexed: 10/20/2022]
Abstract
Some proteins present in snake venom possess enzymatic activities, such as phospholipase A(2) and l-amino acid oxidase. In this study, we verify the action of the Bothrops marajoensis venom (BmarTV), PLA(2) (BmarPLA(2)) and LAAO (BmarLAAO) on strains of bacteria, yeast, and Leishmania sp. The BmarTV was isolated by Protein Pack 5PW, and several fractions were obtained. Reverse phase HPLC showed that BmarPLA(2) was isolated from the venom, and N-terminal amino acid sequencing of sPLA(2) showed high amino acid identity with other lysine K49 sPLA(2)s isolated from Bothrops snakes. The BmarLAAO was purified to high molecular homogeneity and its N-terminal amino acid sequence demonstrated a high degree of amino acid conservation with others LAAOs. BmarLAAO was able to inhibit the growth of P. aeruginosa, C. albicans and S. aureus in a dose-dependent manner. The inhibitory effect was more significant on S. aureus, with a MIC=50 microg/mL and MLC=200 microg/mL. However, the BmarTV and BmarPLA(2) did not demonstrate inhibitory capacity. BmarLAAO was able to inhibit the growth of promastigote forms of L. chagasi and L. amazonensis, with an IC(50)=2.55 microg/mL and 2.86 microg/mL for L. amazonensis and L. chagasi, respectively. BmarTV also provided significant inhibition of parasitic growth, with an IC(50) of 86.56 microg/mL for L. amazonensis and 79.02 microg/mL for L. chagasi. BmarPLA(2) did not promote any inhibition of the growth of these parasites. The BmarLAAO and BmarTV presented low toxicity at the concentrations studied. In conclusion, whole venom as well as the l-amino acid oxidase from Bothrops marajoensis was able to inhibit the growth of several microorganisms, including S. aureus, Candida albicans, Pseudomonas aeruginosa, and Leishmania sp.
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Affiliation(s)
- Alba Fabiola Costa Torres
- Post-graduate Program in Pharmaceutical Sciences, Pharmacy Faculty, Federal University of Ceará, Fortaleza, Ceará, Brazil
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20
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Marchi-Salvador DP, Fernandes CA, Silveira LB, Soares AM, Fontes MR. Crystal structure of a phospholipase A2 homolog complexed with p-bromophenacyl bromide reveals important structural changes associated with the inhibition of myotoxic activity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1794:1583-90. [DOI: 10.1016/j.bbapap.2009.07.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Revised: 07/07/2009] [Accepted: 07/08/2009] [Indexed: 10/20/2022]
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21
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22
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Abstract
Phospholipase A(2) (PLA(2)), a common toxic component of snake venom, has been implicated in various pharmacological effects. Ecarpholin S, isolated from the venom of the snake Echis carinatus sochureki, is a phospholipase A(2) (PLA(2)) belonging to the Ser(49)-PLA(2) subgroup. It has been characterized as having low enzymatic but potent myotoxic activities. The crystal structures of native ecarpholin S and its complexes with lauric acid, and its inhibitor suramin, were elucidated. This is the first report of the structure of a member of the Ser(49)-PLA(2) subgroup. We also examined interactions of ecarpholin S with phosphatidylglycerol and lauric acid, using surface plasmon resonance, and of suramin with isothermal titration calorimetry. Most Ca(2+)-dependent PLA(2) enzymes have Asp in position 49, which plays a crucial role in Ca(2+) binding. The three-dimensional structure of ecarpholin S reveals a unique conformation of the Ca(2+)-binding loop that is not favorable for Ca(2+) coordination. Furthermore, the endogenously bound fatty acid (lauric acid) in the hydrophobic channel may also interrupt the catalytic cycle. These two observations may account for the low enzymatic activity of ecarpholin S, despite full retention of the catalytic machinery. These observations may also be applicable to other non-Asp(49)-PLA(2) enzymes. The interaction of suramin in its complex with ecarpholin S is quite different from that reported for the Lys(49)-PLA(2)/suramin complex(,) where the interfacial recognition face (i-face), C-terminal region, and N-terminal region of ecarpholin S play important roles. This study provides significant structural and functional insights into the myotoxic activity of ecarpholin S and, in general, of non-Asp(49)-PLA(2) enzymes.
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23
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24
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Purification and renal effects of phospholipase A2 isolated from Bothrops insularis venom. Toxicon 2008; 51:181-90. [DOI: 10.1016/j.toxicon.2007.08.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2007] [Revised: 08/21/2007] [Accepted: 08/31/2007] [Indexed: 11/17/2022]
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25
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Jan VM, Guillemin I, Robbe-Vincent A, Choumet V. Phospholipase A2 diversity and polymorphism in European viper venoms: Paradoxical molecular evolution in Viperinae. Toxicon 2007; 50:1140-61. [PMID: 17904178 DOI: 10.1016/j.toxicon.2007.07.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2007] [Revised: 07/30/2007] [Accepted: 07/30/2007] [Indexed: 11/22/2022]
Abstract
We report the diversity and polymorphism of phospholipase A(2) (PLA(2)) transcripts from snakes belonging to nine European viper subspecies. This diversity results in the expression of a combination of six PLA(2) species--ammodytin I1, ammodytin I2, ammodytin L, ammodytoxin, vaspin A and vaspin B--with 19 known isoforms of the first five of these species. Most of the European viper venoms studied contained either a myotoxin or a neurotoxin, and all contained ammodytin I1 and ammodytin I2. There is no evidence that a given pattern of PLA(2) species constitutes a taxonomic criterion, and isoform analysis would be required for such discrimination. Analysis of the phylogenetic relationships between PLA(2) species from European vipers and those of other members of the Viperinae revealed a strong correlation between the geographical source of the viper and the clustering seen for the different isoforms, for each PLA(2) species. The K(a)/K(s) values calculated for the mature protein-coding region of paralogous genes showed that ratios for pairs including vaspin B or one ammodytoxin isoform were greater than 1.09, whereas those for most of the remaining pairs were less than 1. Different patterns of mutation were observed in comparisons of the different PLA(2) isoforms. The mechanisms directing a mutation toward a precise exon remain unresolved.
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Affiliation(s)
- Virginie M Jan
- Unité des Venins, Institut Pasteur, 25 rue du Dr Roux, 75724, Paris Cedex 15, France
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26
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Murakami MT, Kuch U, Betzel C, Mebs D, Arni RK. Crystal structure of a novel myotoxic Arg49 phospholipase A2 homolog (zhaoermiatoxin) from Zhaoermia mangshanensis snake venom: insights into Arg49 coordination and the role of Lys122 in the polarization of the C-terminus. Toxicon 2007; 51:723-35. [PMID: 18295812 DOI: 10.1016/j.toxicon.2007.11.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 11/19/2007] [Accepted: 11/19/2007] [Indexed: 10/22/2022]
Abstract
The venom of Zhaoermia mangshanensis, encountered solely in Mt Mang in China's Hunan Province, exhibits coagulant, phosphodiesterase, l-amino acid oxidase, kallikrein, phospholipase A2 and myotoxic activities. The catalytically inactive PLA2 homolog referred to as zhaoermiatoxin is highly myotoxic and displays high myonecrotic and edema activities. Zhaoermiatoxin possesses a molecular weight of 13,972Da, consists of 121 amino-acid residues cross-linked by seven disulfide bridges and shares high sequence homology with Lys49-PLA2s from the distantly related Asian pitvipers. However, zhaoermiatoxin possesses an arginine residue at position 49 instead of a lysine, thereby suggesting a secondary Lys49-->Arg substitution which results in a catalytically inactive protein. We have determined the first crystal structure of zhaoermiatoxin, an Arg49-PLA2, from Zhaoermia mangshanensis venom at 2.05 angstroms resolution, which represents a novel member of phospholipase A2 family. In this structure, unlike the Lys49 PLA2s, the C-terminus is well ordered and an unexpected non-polarized state of the putative calcium-binding loop due to the flip of Lys122 towards the bulk solvent is observed. The orientation of the Arg-49 side chain results in a similar binding mode to that observed in the Lys49 PLA2s; however, the guadinidium group is tri-coordinated by carbonyl oxygen atoms of the putative calcium-binding loop, whereas the Nzeta atom of lysine is tetra-coordinated as a result of the different conformation adopted by the putative calcium-binding loop.
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Affiliation(s)
- Mário T Murakami
- Center for Structural & Molecular Biology, Department of Physics, IBILCE/UNESP, R. Cristovao Colombo 2265, São José do Rio Preto, São Paulo CEP 15054-000, Brazil
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27
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Petan T, Križaj I, Pungerčar J. Restoration of Enzymatic Activity in a Ser-49 Phospholipase A2 Homologue Decreases Its Ca2+-Independent Membrane-Damaging Activity and Increases Its Toxicity. Biochemistry 2007; 46:12795-809. [DOI: 10.1021/bi701304e] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Toni Petan
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| | - Igor Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| | - Jože Pungerčar
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
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28
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Wei JF, Li T, Wei XL, Sun QY, Yang FM, Chen QY, Wang WY, Xiong YL, He SH. Purification, characterization and cytokine release function of a novel Arg-49 phospholipase A(2) from the venom of Protobothrops mucrosquamatus. Biochimie 2006; 88:1331-42. [PMID: 16793192 DOI: 10.1016/j.biochi.2006.05.003] [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] [Received: 01/02/2006] [Accepted: 05/03/2006] [Indexed: 02/05/2023]
Abstract
Group IIA phospholipase A(2) (PLA(2)) are major components in Viperidae/Crotalidae venom. In the present study, a novel PLA(2) named promutoxin with Arg at the site 49 has been purified from the venom of Protobothrops mucrosquamatus by chromatography. It consists of 122 amino acid residues with a molecular mass of 13,656 Da assessed by MALDI-TOF. It has the structural features of snake venom group IIA PLA(2)s, but has no PLA(2) enzymatic activity. Promutoxin shows higher amino acid sequence identity to the K49 PLA(2)s (72-95%) than to D49 PLA(2)s (52-58%). Promutoxin exhibits potent myotoxicity in the animal model with as little as 1 microg of promutoxin causing myonecrosis and myoedema in the gastrocnemius muscle of mice. Promutoxin is also able to stimulate the release of IL-12, TNFalpha, IL-6 and IL-1beta from human monocytes, and induce IL-2, TNFalpha and IL-6 release from T cells, indicating that this snake venom group IIA PLA(2) is actively involved in the inflammatory process in man caused by snake venom poisoning.
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Affiliation(s)
- Ji-Fu Wei
- Allergy and Inflammation Research Institute, The Shantou University Medical College, Xinling Road 11, 515031 Shantou, Guangdong, China
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29
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Wagstaff SC, Harrison RA. Venom gland EST analysis of the saw-scaled viper, Echis ocellatus, reveals novel α9β1 integrin-binding motifs in venom metalloproteinases and a new group of putative toxins, renin-like aspartic proteases. Gene 2006; 377:21-32. [PMID: 16713134 DOI: 10.1016/j.gene.2006.03.008] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2006] [Revised: 02/15/2006] [Accepted: 03/03/2006] [Indexed: 11/19/2022]
Abstract
Echis ocellatus is the most medically important snake in West Africa. However, the composition of its venom and the differential contribution of these venom components to the severe haemorrhagic and coagulopathic pathology of envenoming are poorly understood. To address this situation we assembled a toxin transcriptome based upon 1000 expressed sequence tags (EST) from a cDNA library constructed from pooled venom glands of 10 individual E. ocellatus. We used a variety of bioinformatic tools to construct a fully annotated venom-toxin transcriptome that was interrogated with a combination of BLAST annotation, gene ontology cataloguing and disintegrin-motif searching. The results of these analyses revealed an unusually abundant and diverse expression of snake venom metalloproteinases (SVMP) and a broad toxin-expression profile including several distinct isoforms of bradykinin-potentiating peptides, phospholipase A(2), C-type lectins, serine proteinases and l-amino oxidases. Most significantly, we identified for the first time a conserved alpha(9)beta(1) integrin-binding motif in several SVMPs, and a new group of putative venom toxins, renin-like aspartic proteases.
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Affiliation(s)
- Simon C Wagstaff
- Alistair Reid Venom Research Unit, Liverpool School of Tropical Medicine, UK.
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30
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Mebs D, Kuch U, Coronas FIV, Batista CVF, Gumprecht A, Possani LD. Biochemical and biological activities of the venom of the Chinese pitviper Zhaoermia mangshanensis, with the complete amino acid sequence and phylogenetic analysis of a novel Arg49 phospholipase A2 myotoxin. Toxicon 2006; 47:797-811. [PMID: 16635500 DOI: 10.1016/j.toxicon.2006.01.031] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 01/24/2006] [Accepted: 01/31/2006] [Indexed: 11/18/2022]
Abstract
Zhaoermia mangshanensis (formerly Trimeresurus mangshanensis, Ermia mangshanensis) represents a monotypic genus of pitviper known only from Mt Mang in China's Hunan Province, and is among the largest and most spectacular of Asian venomous snakes. The venom of Zhaoermia exhibits high coagulant activity on bovine and human fibrinogen and human plasma, high phosphodiesterase and arginine ester hydrolytic activity, and moderate to low l-amino acid oxidase, kallikrein, caseinolytic, phospholipase A(2) (PLA(2)), haemorrhagic and myotoxic activities. The approximate i.p. LD(50) of the venom in mice was estimated to be 4 mg/kg. We purified the major toxin of Zhaoermia venom by gel-filtration, cation-exchange chromatography and HPLC. The toxin, a homodimer with an experimental monomeric mass of 13,972 Da, induced edema and myonecrosis in mice, but was devoid of detectable PLA(2) catalytic activity. Its complete amino acid sequence is composed of 121 amino acid residues cross-linked by seven disulfide bridges, and shows more than 80% identity to two Lys49-PLA(2)s from distantly related Asian pitvipers, Protobothrops mucrosquamatus and Calloselasma rhodostoma. Phylogenetic analysis of the novel toxin, zhaoermiatoxin, confirmed that it is rooted within a comprehensive sample of Lys49-PLA(2)s despite having an arginine residue in position 49, suggesting a secondary Lys49-->Arg substitution which did not alter the catalytic inactivity of the molecule.
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Affiliation(s)
- Dietrich Mebs
- Zentrum der Rechtsmedizin, Klinikum der Johann Wolfgang Goethe-Universität, Kennedyallee 104, D-60596 Frankfurt am Main, Germany
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31
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Wei JF, Wei XL, Chen QY, Huang T, Qiao LY, Wang WY, Xiong YL, He SH. N49 phospholipase A2, a unique subgroup of snake venom group II phospholipase A2. BIOCHIMICA ET BIOPHYSICA ACTA 2006; 1760:462-71. [PMID: 16413680 DOI: 10.1016/j.bbagen.2005.11.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2005] [Revised: 11/28/2005] [Accepted: 11/29/2005] [Indexed: 02/05/2023]
Abstract
A novel phospholipase A2 (PLA2) with Asn at its site 49 was purified from the snake venom of Protobothrops mucrosquamatus by using SP-Sephadex C25, Superdex 75, Heparin-Sepharose (FF) and HPLC reverse-phage C18 chromatography and designated as TM-N49. It showed a molecular mass of 13.875 kDa on MALDI-TOF. TM-N49 does not possess enzymatic, hemolytic and hemorrhagic activities. It fails to induce platelet aggregation by itself, and does not inhibit the platelet aggregation induced by ADP. However, it exhibits potent myotoxic activity causing inflammatory cell infiltration, severe myoedema, myonecrosis and myolysis in the gastrocnemius muscles of BALB/c mice. Phylogenetic analysis found that that TM-N49 combined with two phospholipase A2s from Trimeresurus stejnegeri, TsR6 and CTs-R6 cluster into one group. Structural and functional analysis indicated that these phospholipase A2s are distinct from the other subgroups (D49 PLA2, S49 PLA2 and K49 PLA2) and represent a unique subgroup of snake venom group II PLA2, named N49 PLA2 subgroup.
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Affiliation(s)
- Ji-Fu Wei
- Allergy and Inflammation Research Institute, the Shantou University Medical College, Shantou, Guangdong, 515031, China
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32
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Jabeen T, Singh N, Singh RK, Jasti J, Sharma S, Kaur P, Srinivasan A, Singh TP. Crystal structure of a heterodimer of phospholipase A2 from Naja naja sagittifera at 2.3 Å resolution reveals the presence of a new PLA2-like protein with a novel cys 32-Cys 49 disulphide bridge with a bound sugar at the substrate-binding site. Proteins 2005; 62:329-37. [PMID: 16287060 DOI: 10.1002/prot.20708] [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: 11/08/2022]
Abstract
The crystal structure of the phospholipase A2 (PLA2) heterodimer from Naja naja sagittifera reveals the presence of a new PLA2-like protein with eight disulphide bridges. The heterodimer is formed between a commonly observed group I PLA2 having seven characteristic disulfide bonds and a novel PLA2-like protein (Cys-PLA2) containing two extra cysteines at two highly conserved sites (positions 32 and 49) of structural and functional importance. The crystals of the heterodimer belong to tetragonal space group P41212 with cell dimensions, a = b = 77.7 A and c = 68.4 A corresponding to a solvent content of 33%, which is one of the lowest values observed so far in the PLA2 crystals. The structure has been solved with molecular replacement method and refined to a final R value of 21.6% [Rfree = 25.6%]. The electron density revealed the presence of cysteines 32 and 49 that are covalently linked to give rise to an eighth disulphide bridge in the PLA2-like monomer. A non-protein high-quality electron density was also observed at the substrate-binding site in the PLA2-like protein that has been interpreted as N-acetylglucosamine. The overall tertiary folds of the two monomers are similar having all features of PLA2-type folding. A zinc ion is detected at the interface of the heterodimer with fivefold coordination while another zinc ion was found on the surface of Cys-PLA2 with sixfold coordination. The conformations of the calcium-binding loops of both monomers are significantly different from each other as well as from those in other group I PLA2s. The N-acetylglucosamine molecule is favorably placed in the substrate-binding site of Cys-PLA2 and forms five hydrogen bonds and several van der Waals interactions with protein atoms, thus indicating a strong affinity. It also provides clue of the possible mechanism of sugar recognition by PLA2 and PLA2-like proteins. The formation of heterodimer seems to have been induced by zinc ion.
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Affiliation(s)
- Talat Jabeen
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
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33
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Gutiérrez JM, Ownby CL. Skeletal muscle degeneration induced by venom phospholipases A2: insights into the mechanisms of local and systemic myotoxicity. Toxicon 2004; 42:915-31. [PMID: 15019491 DOI: 10.1016/j.toxicon.2003.11.005] [Citation(s) in RCA: 317] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Local and systemic skeletal muscle degeneration is a common consequence of envenomations due to snakebites and mass bee attacks. Phospholipases A2 (PLA2) are important myotoxic components in these venoms, inducing a similar pattern of degenerative events in muscle cells. Myotoxic PLA2s bind to acceptors in the plasma membrane, which might be lipids or proteins and which may differ in their affinity for the PLA2s. Upon binding, myotoxic PLA2s disrupt the integrity of the plasma membrane by catalytically dependent or independent mechanisms, provoking a pronounced Ca2+ influx which, in turn, initiates a complex series of degenerative events associated with hypercontraction, activation of calpains and cytosolic Ca(2+)-dependent PLA2s, and mitochondrial Ca2+ overload. Cell culture models of cytotoxicity indicate that some myotoxic PLA2s affect differentiated myotubes in a rather selective fashion, whereas others display a broad cytolytic effect. A model is presented to explain the difference between PLA2s that induce predominantly local myonecrosis and those inducing both local and systemic myotoxicity. The former bind not only to muscle cells, but also to other cell types, thereby precluding a systemic distribution of these PLA2s and their action on distant muscles. In contrast, PLA2s that bind muscle cells in a more selective way are not sequestered by non-specific interactions with other cells and, consequently, are systemically distributed and reach muscle cells in other locations.
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Affiliation(s)
- José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica.
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34
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Lomonte B, Angulo Y, Calderón L. An overview of lysine-49 phospholipase A2 myotoxins from crotalid snake venoms and their structural determinants of myotoxic action. Toxicon 2003; 42:885-901. [PMID: 15019489 DOI: 10.1016/j.toxicon.2003.11.008] [Citation(s) in RCA: 229] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In 1984, the first venom phospholipase A2 (PLA2) with a lysine substituting for the highly conserved aspartate 49 was discovered, in the North American crotalid snake Agkistrodon p. piscivorus [J. Biol. Chem. 259 (1984) 13839]. Ten years later, the first mapping of a 'toxic region' on a Lys49 PLA2 was reported, in Bothrops asper myotoxin II [J. Biol. Chem. 269 (1994) 29867]. After a further decade of research on the Lys49 PLA2s, a better understanding of their structural determinants of toxicity and mode of action is rapidly emerging, with myotoxic effector sites identified at the C-terminal region in at least four proteins: B. asper myotoxin II, A. p. piscivorus K49 PLA2, A. c. laticinctus ACL myotoxin, and B. jararacussu bothropstoxin I. Although important features still remain to be established, their toxic mode of action has now been understood in its more general concepts, and a consistent working hypothesis can be experimentally supported. It is proposed that all the toxic activities of Lys49 PLA2s are related to their ability to destabilize natural (eukaryotic and prokaryotic) and artificial membranes, using a cationic/hydrophobic effector site located at their C-terminal loop. This review summarizes the general properties of the Lys49 PLA2 myotoxins, emphasizing the development of current concepts and hypotheses concerning the molecular basis of their toxic activities.
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Affiliation(s)
- Bruno Lomonte
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, San José, Costa Rica.
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Murakami MT, Arni RK. A structure based model for liposome disruption and the role of catalytic activity in myotoxic phospholipase A2s. Toxicon 2003; 42:903-13. [PMID: 15019490 DOI: 10.1016/j.toxicon.2003.11.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Venom phospholipase A2s (PLA2s) display a wide spectrum of pharmacological activities and, based on the wealth of biochemical and structural data currently available for PLA2s, mechanistic models can now be inferred to account for some of these activities. A structural model is presented for the role played by the distribution of surface electrostatic potential in the ability of myotoxic D49/K49 PLA2s to disrupt multilamellar vesicles containing negatively charged natural and non-hydrolyzable phospholipids. Structural evidence is provided for the ability of K49 PLA2s to bind phospholipid analogues and for the existence of catalytic activity in K49 PLA2s. The importance of the existence of catalytic activity of D49 and K49 PLA2s in myotoxicity is presented.
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Affiliation(s)
- M T Murakami
- Department of Biophysics, IBILCE/UNESP, R. Cristovão Colombo 2265, CEP 15054-000, São José do Rio Preto-SP, Brazil
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Bharati K, Hasson SS, Oliver J, Laing GD, Theakston RDG, Harrison RA. Molecular cloning of phospholipases A(2) from venom glands of Echis carpet vipers. Toxicon 2003; 41:941-7. [PMID: 12875867 DOI: 10.1016/s0041-0101(02)00312-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Venom toxin-specific antibodies offer a more rational treatment of snake envenoming than conventional antivenom. Here, we describe novel cDNAs encoding phospholipase A(2) (PLA(2)) isoforms from venom gland RNA of Echis pyramidum leakeyi (Epl), Echis sochureki (Es) and Echis ocellatus (Eo). The deduced amino acid sequences of these cDNAs encoded proteins with high overall sequence identity to the viper group II PLA(2) protein family, including the 14 cysteine residues capable of forming seven disulphide bonds that characterize this group of PLA(2) enzymes. Comparison of the PLA(2) sequences from Echis with those from related vipers failed to make significant geographic, taxonomic or PLA(2)-function distinctions between these Echis PLA(2) isoforms. However, their deduced hydrophilicity profiles revealed a conserved tertiary structure that we will exploit, by epidermal DNA immunization, to generate PLA(2)-neutralizing antibodies with polyspecific potential.
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Affiliation(s)
- K Bharati
- Alistair Reid Venom Research Unit, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK
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Angulo Y, Olamendi-Portugal T, Alape-Girón A, Possani LD, Lomonte B. Structural characterization and phylogenetic relationships of myotoxin II from Atropoides (Bothrops) nummifer snake venom, a Lys49 phospholipase A(2) homologue. Int J Biochem Cell Biol 2002; 34:1268-78. [PMID: 12127577 DOI: 10.1016/s1357-2725(02)00060-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In order to analyze its structure-function relationships, the complete amino acid sequence of myotoxin II from Atropoides (Bothrops) nummifer from Costa Rica was determined. This toxin is a Lys49-type phospholipase A(2) (PLA(2)) homologue, devoid of catalytic activity, structurally belonging to class IIA. In addition to the Asp49 --> Lys change in the (inactive) catalytic center, substitutions in the calcium-binding loop suggest that its lack of enzymatic activity is due to the loss of ability to bind Ca(2+). The toxin occurs as a homodimer of basic subunits of 121 residues. Its sequence has highest similarity to Lys49 PLA(2)s from Cerrophidion, Trimeresurus, Bothrops and Agkistrodon species, which form a subfamily of proteins that diverged early from Asp49 PLA(2)s present in the same species, as shown by phylogenetic analysis. The tertiary structure of the toxin was modeled, based on the coordinates of Cerrophidion godmani myotoxin II. Its exposed C-terminal region 115-129 shows several differences in comparison to the homologous sequences of other Lys49 PLA(2)s, i.e. from Agkistrodon p. piscivorus and Bothrops asper. Region 115-129 of the latter two proteins has been implicated in myotoxic activity, on the basis of the direct membrane-damaging of their corresponding synthetic peptides. However, peptide 115-129 of A. nummifer myotoxin II did not exert toxicity upon cultured skeletal muscle cells or mature muscle in vivo. Differences in several amino acid residues, either critical for toxicity, or influencing the conformation of free peptide 115-129 from A. nummifer myotoxin II, may account for its lack of direct membrane-damaging properties.
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Affiliation(s)
- Yamileth Angulo
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
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Lu QM, Jin Y, Wei JF, Li DS, Zhu SW, Wang WY, Xiong YL. Characterization and cloning of a novel phospholipase A(2) from the venom of Trimeresurus jerdonii snake. Toxicon 2002; 40:1313-9. [PMID: 12220717 DOI: 10.1016/s0041-0101(02)00141-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A phospholipase A(2) (PLA(2)), called jerdoxin, was isolated from Trimeresurus jerdonni snake venom and partially characterized. The protein was purified by three chromatographic steps. SDS-polyacrylamide gel electrophoresis in the presence or absence of dithiothreitol showed that it had a molecular mass of 15 kDa. Jerdoxin had an enzymatic activity of 39.4 micro mol/min/mg towards egg yolk phosphatidyl choline (PC). It induced edema in the footpads of mice. In addition, jerdoxin exhibited indirect hemolytic activity. About 97% hemolysis was observed when 2 micro g/ml enzyme was incubated for 90 min in the presence of PC and Ca(2+). No detectable hemolysis was noticed when PC was not added. Ca(2+) was necessary for jerdoxin to exert its hemolytic activity, since only 52% hemolysis was seen when Ca(2+) was absent in the reaction mixture. Furthermore, jerdoxin inhibited ADP induced rabbit platelet aggregation and the inhibition was dose dependent with an IC(50) of 1.0 micro M. The complete amino acid sequence of jerdoxin deduced from cDNA sequence shared high homology with other snake venom PLA(2)s, especially the D 49 PLA(2)s. Also, the residues concerned to Ca(2+) binding were conserved. This is the first report of cDNA sequence of T. jerdonii venom PLA(2).
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Affiliation(s)
- Qiu-Min Lu
- Department of Animal Toxicology, Kunming Institute of Zoology, Chinese Academy of Sciences, 650223, Yunnan, Kunming, People's Republic of China
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Guerranti R, Aguiyi JC, Neri S, Leoncini R, Pagani R, Marinello E. Proteins from Mucuna pruriens and enzymes from Echis carinatus venom: characterization and cross-reactions. J Biol Chem 2002; 277:17072-8. [PMID: 11867642 DOI: 10.1074/jbc.m201387200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mucuna pruriens seeds have been widely used against snakebite in traditional medicine. The antivenin property of a water extract of seeds was assessed in vivo in mice. The serum of mice treated with extract was tested for its immunological properties. Two proteins of Echis carinatus venom with apparent molecular masses of 25 and 16 kDa were detected by Western blot analysis carried out using IgG of mice immunized with extract or its partially purified protein fractions. By enzymatic in-gel digestion and electrospray ionization-mass spectrometry/mass spectrometry analysis of immunoreactive venom proteins, phospholipase A(2,) the most toxic enzyme of snake venom, was identified. These results demonstrate that the observed antivenin activity has an immune mechanism. Antibodies of mice treated with non-lethal doses of venom reacted against some proteins of M. pruriens extract. Proteins of E. carinatus venom and M. pruriens extract have at least one epitope in common as confirmed by immunodiffusion assay.
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Affiliation(s)
- Roberto Guerranti
- Institute of Biochemistry and Enzymology, University of Siena, Via A. Moro 2, 53100 Siena, Italy
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Guerranti R, Aguiyi JC, Errico E, Pagani R, Marinello E. Effects of Mucuna pruriens extract on activation of prothrombin by Echis carinatus venom. JOURNAL OF ETHNOPHARMACOLOGY 2001; 75:175-180. [PMID: 11297847 DOI: 10.1016/s0378-8741(00)00401-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Mucuna pruriens (L.) DC has long been used as a medicinal plant by traditional healers. The validity of the claims made for this plant has also been tested scientifically. Some of its properties are probably linked to high concentrations of dopa since it is useful in the treatment of Parkinson's disease. The antisnake properties of an extract of Mucuna pruriens' seeds (MP101UJ) in vivo were recently demonstrated and one is now investigating its biochemical mechanism. Echis carinatus venom (EV) contains a mixture of proteins that affect the coagulative cascade, causing severe bleeding and haemorrhage. Here the effect of an extract of MP101UJ in prothrombin activation by EV in vitro by clotting and chromogenic assay is studied. An increase in procoagulant activity was found. This could explain the protective effect in vivo.
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Affiliation(s)
- R Guerranti
- Institute of Biochemistry and Enzymology, University of Siena, Via A. Moro, 53100, Siena, Italy.
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Ali SA, Alam JM, Stoeva S, Schütz J, Abbasi A, Zaidi ZH, Voelter W. Sea snake Hydrophis cyanocinctus venom. I. Purification, characterization and N-terminal sequence of two phospholipases A2. Toxicon 1999; 37:1505-20. [PMID: 10482386 DOI: 10.1016/s0041-0101(99)00091-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Two phospholipases A2 (PLA2, H1 and H2) from sea snake Hydrophis cyanocinctus venom were purified to homogeneity in a single step using reversed-phase high performance liquid chromatography on a Nucleosil 7C18 column. The molecular weights of H1 and H2, as estimated by MALDI MS, were 13588.1 and 13247.2 Da, respectively. The N-terminal 60 amino acid residues were determined by direct automated Edman degradation analysis. Since both PLA2s show close sequence homologies to those of PLA2s from other Elapid snakes (60-84%) they have been tentatively classified as belonging to group-IA and Asp-49 phospholipases A2. Despite the sequence variation (18%) between H1 and H2, their general structural organization is very similar as shown by their clearly related CD spectra. Furthermore, both enzymes are quite thermostable (60-65 degrees C) as determined by temperature variable CD spectra, indicating that the enzymes contain compact folded structure, mainly based on the core structure of disulfide bridges. However, the major PLA2 (H1) shows higher toxicity to albino rats (LD50 i.p. 0.04 mg/kg) and purification resulted in 18-fold increase in toxicity over the crude or whole venom (LD50 i.p. 0.80 mg/kg). H1 also shows edema-inducing and indirect haemolytic but no haemorrhagic activity. Unlike the toxic PLA2-H1, enzyme H2 was not toxic to albino rats but showed edema-inducing and indirect haemolytic activities.
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Affiliation(s)
- S A Ali
- International Center for Chemical Sciences, HEJ Research Institute of Chemistry, University of Karachi, Pakistan.
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Abstract
The structures of several K49 PLA2 proteins have been determined and these differ as a group in several regions from the closely related D49 PLA2 enzymes. One outstanding difference is the presence of a high number of positively charged residues in the C-terminal region which combined with the overall high number of conserved lysine residues gives the molecule an interfacial adsorption surface which is highly positively charged compared to the opposite surface of the molecule. Although some nucleotide sequences have been reported, progress in obtaining active recombinant proteins has been slow. The K49 proteins exert several toxic activities, including myotoxicity, anticoagulation and edema formation. The most studied of these activities is myotoxicity. The myotoxicity induced by the K49 PLA2 proteins is histologically similar to that caused by the D49 PLA2 myotoxins, with some muscle fiber types possibly more sensitive than others. Whereas it is clear that the K49 PLA2 myotoxins lyse the plasma membrane of the affected muscle cell in vivo, the exact mechanism of this lysis is not known. Also, it is not known whether the toxin is internalized before, during or after the initial lysis or ever. The K49 PLA2 toxins lyse liposomes and cells in culture and in the latter, the PLA2 myotoxins exert at least two distinct mechanisms of action, neither of which is well-characterized. While the K49 PLA2 proteins are enzymatically inactive on artificial substrates, the toxins cause fatty acid production in cell cultures. Whether the fatty acid release is due to the enzymatic activity of the K49 PLA2 or stimulation of tissue lipases, is unknown. While there may be a role for fatty acid production in one mechanism of myotoxicity, a second mechanism appears to be independent of enzymatic activity. Although we are beginning to understand more about the structure of these toxins, we still know little about the precise mechanism by which they interact with the skeletal muscle cell in vivo.
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Affiliation(s)
- C L Ownby
- Department of Anatomy, Pathology and Pharmacology, Oklahoma State University, Stillwater 74078-0350, USA.
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Pungercar J, Vucemilo N, Faure G, Bon C, Verheij HM, Gubensek F, Krizaj I. Ammodytin L, an inactive phospholipase A2 homologue with myotoxicity in mice, binds to the presynaptic acceptor of the beta-neurotoxic ammodytoxin C in Torpedo: an indication for a phospholipase A2 activity-independent mechanism of action of beta-neurotoxins in fish? Biochem Biophys Res Commun 1998; 244:514-8. [PMID: 9514950 DOI: 10.1006/bbrc.1998.8297] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A Ser48 phospholipase A2-homologue, ammodytin L, which is myotoxic in mammals and devoid of any phospholipase A2 activity, completely inhibits the specific binding of the neurotoxic phospholipase A2, ammodytoxin C, to fish presynaptic membranes from Torpedo marmorata electric organ. In cross-linking experiments, 125I-ammodytin L labels the same membrane proteins as 125I-ammodytoxin C (70, 38.5-57.4 and 19.7 kDa). The formation of these adducts is completely prevented by the presence of ammodytoxin C but not of a non-toxic phospholipase A2, ammodytin I2. A chimeric phospholipase A2, constructed by associating the N-terminal half of ammodytoxin to the C-terminal half of ammodytin L, possesses a low, but significant phospholipase A2 activity, however it is not toxic to mice, probably due to abolition of the specific neuronal acceptor binding in mammals. Nevertheless, the chimeric phospholipase A2 is able to interact with the ammodytoxin acceptor in Torpedo marmorata electric organ. The existence of neuronal acceptors for ammodytin L and for the chimeric phospholipase A2 suggests that they may act as neurotoxins in fish. As ammodytin L does not possess any enzymatic activity it, therefore, appears to be an excellent tool to investigate the mechanism of action of beta-neurotoxins independently of their phospholipase A2 activity.
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Affiliation(s)
- J Pungercar
- Department of Biochemistry and Molecular Biology, Jozef Stefan Institute, Jamova, Slovenia
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