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Pedro G, Brasileiro FCDS, Macedo JM, Soares AM, Mafra GC, Alves CEF, Laufer-Amorim R. Cytotoxic effects of crotoxin from Crotalus durissus terrificus snake in canine mammary tumor cell lines. J Venom Anim Toxins Incl Trop Dis 2024; 30:e20230062. [PMID: 38505509 PMCID: PMC10950368 DOI: 10.1590/1678-9199-jvatitd-2023-0062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 02/16/2024] [Indexed: 03/21/2024] Open
Abstract
Background Mammary gland tumors are the most prevalent neoplasm in intact female dogs, and they are good natural models to study comparative oncology. Most canine mammary malignancies, as in women, are commonly refractory to conventional therapies and demand continuous new therapeutic approaches. Crotalus durissus terrificus, also called rattlesnake, has more than 60 different proteins in its venom with multiple pharmaceutical uses, such as antitumor, antiviral, and antimicrobial action. Crotoxin, a potent β-neurotoxin formed by the junction of two subunits, a basic subunit (CB-PLA2) and an acidic subunit (crotapotin), has already been reported to have anticancer properties in different types of cancers. Methods In this work, we describe the cytotoxic potential of crotoxin and its subunits compared to doxorubicin (drug of choice) in two canine mammary carcinoma cell lines. Results Crotoxin, CB-PLA2, crotalic venom, and doxorubicin decreased cell viability and the ability to migrate in a dose-dependent manner, and crotapotin did not present an antitumoral effect. For all compounds, the predominant cell death mechanism was apoptosis. In addition, crotoxin did not show toxicity in normal canine mammary gland cells. Conclusion Therefore, this work showed that crotoxin and CB-PLA2 had cytotoxic activity, migration inhibition, and pro-apoptotic potential in canine mammary gland carcinoma cell lines, making their possible use in cancer research.
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Affiliation(s)
- Giovana Pedro
- School of Veterinary Medicine and Animal Science, São Paulo State University (UNESP), Botucatu, SP, Brazil
| | | | - Jamile Mariano Macedo
- Laboratory of Biotechnology and Education Applied to One Health (LABIOPROT), Oswaldo Cruz Foundation, Fiocruz - Porto Velho, RO, Brazil
- Federal University of Rondônia (UNIR), Porto Velho, RO, Brazil
- São Lucas University Center - São Lucas PVH, Porto Velho, RO, Brazil
| | - Andreimar Martins Soares
- Laboratory of Biotechnology and Education Applied to One Health (LABIOPROT), Oswaldo Cruz Foundation, Fiocruz - Porto Velho, RO, Brazil
- Federal University of Rondônia (UNIR), Porto Velho, RO, Brazil
- São Lucas University Center - São Lucas PVH, Porto Velho, RO, Brazil
- Western Amazon Research and Knowledge Network of Excellence (RED-CONEXAO), Porto Velho, RO, Brazil
- National Institute of Science and Technology of Epidemiology of the Western Amazon (INCT EpiAmO), Porto Velho, RO, Brazil
| | - Gabriel Caporale Mafra
- School of Veterinary Medicine and Animal Science, São Paulo State University (UNESP), Botucatu, SP, Brazil
| | | | - Renée Laufer-Amorim
- School of Veterinary Medicine and Animal Science, São Paulo State University (UNESP), Botucatu, SP, Brazil
- Western Amazon Research and Knowledge Network of Excellence (RED-CONEXAO), Porto Velho, RO, Brazil
- National Institute of Science and Technology of Epidemiology of the Western Amazon (INCT EpiAmO), Porto Velho, RO, Brazil
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Salvador GHM, Fernandes CAH, Borges RJ, Soares AM, Fontes MRM. Structural studies with crotoxin B from Crotalus durissus collilineatus venom suggest a heterodimeric assembly formed by two new isoforms. Biochimie 2024; 218:46-56. [PMID: 37659716 DOI: 10.1016/j.biochi.2023.08.018] [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: 04/17/2023] [Revised: 08/07/2023] [Accepted: 08/31/2023] [Indexed: 09/04/2023]
Abstract
In accidents involving Crotalus snakes, the crotoxin complex (CTX) plays lethal action due to its neurotoxic activity. On the other hand, CTX have potential biotechnological application due to its anti-tumoral, anti-inflammatory, antimicrobial, analgesic and immunomodulatory properties. CTX is a heterodimer composed of Crotoxin A (CA or crotapotin), the acidic nontoxic and non-enzymatic component and; Crotoxin B (CB), a basic, toxic and catalytic PLA2. Currently, there are two classes of CTX isoforms, whose differences in their biological activities have been attributed to features presented in CB isoforms. Here, we present the crystal structure of CB isolated from the Crotalus durissus collilineatus venom. It amino acid sequence was assigned using the SEQUENCE SLIDER software, which revealed that the crystal structure is a heterodimer composed of two new CB isoforms (colCB-A and colCB-B). Bioinformatic and biophysical analyses showed that the toxin forms a tetrameric assembly in solution similar to CB from Crotalus durissus terrificus venom, despite some differences observed at the dimeric interface. By the previously proposed classification, the colCB-B presents features of the class I isoforms while colCB-A cannot be classified into classes I and II based on its amino acid sequence. Due to similar features observed for other CB isoforms found in the NCBI database and the results obtained for colCB-A, we suggest that there are more than two classes of CTX and CB isoforms in crotalic venoms.
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Affiliation(s)
- Guilherme H M Salvador
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil
| | - Carlos A H Fernandes
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil; UMR 7590, CNRS, Muséum National d'Histoire Naturelle, IRD, Institut de Minéralogie, Physique des Matériaux et de Cosmochimie (IMPMC), Sorbonne Université, Paris, France
| | - Rafael J Borges
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil; Centro de Química Medicina (CQMED), Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade de Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Andreimar M Soares
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos Aplicados, Fundação Oswaldo Cruz (FIOCRUZ), Unidade Rondônia, Porto Velho, RO, Brazil; Inst Nac. de Epidemiologia da Amazônia Ocidental (INCT-EPIAMO), Rede de Pesquisa e Conhecimento de Excelência na Amazônia Ocidental (RED-CONEXAO), Brazil
| | - Marcos R M Fontes
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil; Instituto de Estudos Avançados do Mar (IEAMar), Universidade Estadual Paulista (UNESP), São Vicente, SP, Brazil.
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Belchor MN, Costa CRDC, Roggero A, Moraes LLF, Samelo R, Annunciato I, de Oliveira MA, Sousa SF, Toyama MH. In Silico Evaluation of Quercetin Methylated Derivatives on the Interaction with Secretory Phospholipases A2 from Crotalus durissus terrificus and Bothrops jararacussu. Pharmaceuticals (Basel) 2023; 16:ph16040597. [PMID: 37111354 PMCID: PMC10143728 DOI: 10.3390/ph16040597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Quercetin derivatives have already shown their anti-inflammatory potential, inhibiting essential enzymes involved in this process. Among diverse pro-inflammatory toxins from snake venoms, phospholipase A2 is one of the most abundant in some species, such as Crotalus durissus terrificus and Bothrops jararacussu from the Viperidae family. These enzymes can induce the inflammatory process through hydrolysis at the sn-2 position of glycerophospholipids. Hence, elucidating the main residues involved in the biological effects of these macromolecules can help to identify potential compounds with inhibitory activity. In silico tools were used in this study to evaluate the potential of quercetin methylated derivatives in the inhibition of bothropstoxin I (BthTX-I) and II (BthTX-II) from Bothrops jararacussu and phospholipase A2 from Crotalus durissus terrificus. The use of a transitional analogous and two classical inhibitors of phospholipase A2 guided this work to find the role of residues involved in the phospholipid anchoring and the subsequent development of the inflammatory process. First, main cavities were studied, revealing the best regions to be inhibited by a compound. Focusing on these regions, molecular docking assays were made to show main interactions between each compound. Results reveal that analogue and inhibitors, Varespladib (Var) and p-bromophenacyl bromide (BPB), guided quercetins derivatives analysis, revealing that Leu2, Phe5, Tyr28, glycine in the calcium-binding loop, His48, Asp49 of BthTX-II and Cdtspla2 were the main residues to be inhibited. 3MQ exhibited great interaction with the active site, similar to Var results, while Q anchored better in the BthTX-II active site. However, strong interactions in the C-terminal region, highlighting His120, seem to be crucial to decreasing contacts with phospholipid and BthTX-II. Hence, quercetin derivatives anchor differently with each toxin and further in vitro and in vivo studies are essential to elucidate these data.
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Affiliation(s)
- Mariana Novo Belchor
- Center of Natural and Human Sciences, Federal University of ABC (UFABC), Santo André 09210-580, SP, Brazil
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Caroline Ramos da Cruz Costa
- Center of Natural and Human Sciences, Federal University of ABC (UFABC), Santo André 09210-580, SP, Brazil
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Airam Roggero
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Laila L F Moraes
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Ricardo Samelo
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Isabelly Annunciato
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Marcos Antonio de Oliveira
- Center of Natural and Human Sciences, Federal University of ABC (UFABC), Santo André 09210-580, SP, Brazil
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
| | - Sergio F Sousa
- Unit of Applied Biomolecular Sciences (UCIBIO), REQUIMTE-BioSIM-Medicine Faculty, Porto University, 4050-345 Porto, Portugal
| | - Marcos Hikari Toyama
- Center of Natural and Human Sciences, Federal University of ABC (UFABC), Santo André 09210-580, SP, Brazil
- Biosciences Institute of Paulista Coast Campus (IB/CLP), University of São Paulo State (UNESP), São Vicente 11330-900, SP, Brazil
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Sialic acid-containing glycans play a role in the activity of snake venom proteases. Biochimie 2023; 204:140-153. [PMID: 36210615 DOI: 10.1016/j.biochi.2022.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/31/2022] [Accepted: 09/14/2022] [Indexed: 01/12/2023]
Abstract
Structural variability is a feature of snake venom proteins, and glycosylation is a post-translational modification that contributes to the diversification of venom proteomes. Studies by our group have shown that Bothrops venoms are distinctly defined by their glycoprotein content, and that most hybrid/complex N-glycans identified in these venoms contain sialic acid. Considering that metalloproteases and serine proteases are abundant components of Bothrops venoms and essential in the envenomation process, and that these enzymes contain several glycosylation sites, the role of sialic acid in venom proteolytic activity was evaluated. Here we show that removal of sialic acid by treatment of nine Bothrops venoms with neuraminidase (i) altered the pattern of gelatinolysis in zymography of most venoms and reduced the gelatinolytic activity of all venoms, (ii) decreased the proteolytic activity of some venoms on fibrinogen and the clotting activity of human plasma of all venoms, and (iii) altered the proteolysis profile of plasma proteins by B. jararaca venom, suggesting that sialic acid may play a role in the interaction of proteases with their protein substrates. In contrast, the profile of venom amidolytic activity on Bz-Arg-pNA did not change after removal of sialic acid, indicating that this monosaccharide is not essential in N-glycans of serine proteases acting on small substrates. In summary, these results expand the knowledge about the variability of the subproteomes of Bothrops venom proteases, and for the first time point to the importance of carbohydrate chains containing sialic acid in the enzymatic activities of venom proteases relevant in human envenomation.
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Correlating biological activity to thermo-structural analysis of the interaction of CTX with synthetic models of macrophage membranes. Sci Rep 2021; 11:23712. [PMID: 34887428 PMCID: PMC8660830 DOI: 10.1038/s41598-021-02552-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 11/11/2021] [Indexed: 11/10/2022] Open
Abstract
The important pharmacological actions of Crotoxin (CTX) on macrophages, the main toxin in the venom of Crotalus durissus terrificus, and its important participation in the control of different pathophysiological processes, have been demonstrated. The biological activities performed by macrophages are related to signaling mediated by receptors expressed on the membrane surface of these cells or opening and closing of ion channels, generation of membrane curvature and pore formation. In the present work, the interaction of the CTX complex with the cell membrane of macrophages is studied, both using biological cells and synthetic lipid membranes to monitor structural alterations induced by the protein. Here we show that CTX can penetrate THP-1 cells and induce pores only in anionic lipid model membranes, suggesting that a possible access pathway for CTX to the cell is via lipids with anionic polar heads. Considering that the selectivity of the lipid composition varies in different tissues and organs of the human body, the thermostructural studies presented here are extremely important to open new investigations on the biological activities of CTX in different biological systems.
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Almeida CF, Amaral C, Augusto TV, Correia-da-Silva G, Marques de Andrade C, Torqueti MR, Teixeira N. The anti-cancer potential of crotoxin in estrogen receptor-positive breast cancer: Its effects and mechanism of action. Toxicon 2021; 200:69-77. [PMID: 34265323 DOI: 10.1016/j.toxicon.2021.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/05/2021] [Accepted: 07/08/2021] [Indexed: 12/24/2022]
Abstract
Estrogen receptor-positive (ER+) breast cancer is the most diagnosed subtype of breast cancer. Currently, aromatase inhibitors (AIs) are used as first-line treatment option in this type of tumors, however they cause several side effects, which is why new therapeutic approaches are demanding. The South American rattlesnake Crotalus durissus terrificus produces a venom enriched in several bioactive substances, like phospholipases A2 (PLA2). One of those is crotoxin, a β-neurotoxin, that has already been reported for its anti-cancer properties in different cancers. Recently, its clinical interest has emerged and, in fact, a clinical trial in patients with advanced cancer is underway. Considering this, in this work, we studied the biological mechanisms behind the anti-cancer effects of crotoxin B (CTX) in an ER+ aromatase-overexpressing breast cancer cell line (MCF-7aro cells). Results revealed that CTX impairs MCF-7aro cells growth, through a cell cycle arrest at G2/M phase, inhibition of ERK1/2 pathway and by apoptosis through activation of caspase-8. In addition, it can be considered a safe natural compound as did not affect non-cancerous cells and only showed anti-growth effects in breast cancer cells. Therefore, this study represents an important landmark to better understand the effects and mechanisms of action of crotoxin in ER+ breast cancer.
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Affiliation(s)
- Cristina Ferreira Almeida
- UCIBIO.REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313, Porto, Portugal
| | - Cristina Amaral
- UCIBIO.REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313, Porto, Portugal.
| | - Tiago V Augusto
- UCIBIO.REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313, Porto, Portugal
| | - Georgina Correia-da-Silva
- UCIBIO.REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313, Porto, Portugal
| | - Camila Marques de Andrade
- Laboratory of Clinical Cytology, Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, Brazil
| | - Maria Regina Torqueti
- Laboratory of Clinical Cytology, Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, Brazil
| | - Natércia Teixeira
- UCIBIO.REQUIMTE, Laboratory of Biochemistry, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313, Porto, Portugal.
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Andrade-Silva D, Zelanis A, Travaglia-Cardoso SR, Nishiyama MY, Serrano SMT. Venom Profiling of the Insular Species Bothrops alcatraz: Characterization of Proteome, Glycoproteome, and N-Terminome Using Terminal Amine Isotopic Labeling of Substrates. J Proteome Res 2021; 20:1341-1358. [PMID: 33404253 DOI: 10.1021/acs.jproteome.0c00737] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Bothrops alcatraz, a species endemic to Alcatrazes Islands, is regarded as critically endangered due to its small area of occurrence and the declining quality of its habitat. We recently reported the identification of N-glycans attached to toxins of Bothrops species, showing similar compositions in venoms of the B. jararaca complex (B. jararaca, B. insularis, and B. alcatraz). Here, we characterized B. alcatraz venom using electrophoretic, proteomic, and glycoproteomic approaches. Electrophoresis showed that B. alcatraz venom differs from B. jararaca and B. insularis; however, N-glycan removal revealed similarities between them, indicating that the occupation of N-glycosylation sites contributes to interspecies variability in the B. jararaca complex. Metalloproteinase was the major toxin class identified in the B. alcatraz venom proteome followed by serine proteinase and C-type lectin, and overall, the adult B. alcatraz venom resembles that of B. jararaca juvenile specimens. The comparative glycoproteomic analysis of B. alcatraz venom with B. jararaca and B. insularis indicated that there may be differences in the utilization of N-glycosylation motifs among their different toxin classes. Furthermore, we prospected for the first time the N-terminome of a snake venom using the terminal amine isotopic labeling of substrates (TAILS) approach and report the presence of ∼30% of N-termini corresponding to truncated toxin forms and ∼37% N-terminal sequences blocked by pyroglutamic acid in B. alcatraz venom. These findings underscore a low correlation between venom gland transcriptomes and proteomes and support the view that post-translational processes play a major role in shaping venom phenotypes.
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Affiliation(s)
- Débora Andrade-Silva
- Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo 05503-900, Brazil
| | - André Zelanis
- Functional Proteomics Laboratory, Department of Science and Technology, Federal University of São Paulo, (ICT-UNIFESP), São José dos Campos 12231-280, SP, Brazil
| | | | - Milton Y Nishiyama
- Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo 05503-900, Brazil
| | - Solange M T Serrano
- Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo 05503-900, Brazil
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Nemecz D, Ostrowski M, Ravatin M, Saul F, Faure G. Crystal Structure of Isoform CBd of the Basic Phospholipase A 2 Subunit of Crotoxin: Description of the Structural Framework of CB for Interaction with Protein Targets. Molecules 2020; 25:molecules25225290. [PMID: 33202772 PMCID: PMC7696373 DOI: 10.3390/molecules25225290] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/06/2020] [Accepted: 11/11/2020] [Indexed: 11/16/2022] Open
Abstract
Crotoxin, from the venom of the South American rattlesnake Crotalus durissus terrificus, is a potent heterodimeric presynaptic β-neurotoxin that exists in individual snake venom as a mixture of isoforms of a basic phospholipase A2 (PLA2) subunit (CBa2, CBb, CBc, and CBd) and acidic subunit (CA1-4). Specific natural mutations in CB isoforms are implicated in functional differences between crotoxin isoforms. The three-dimensional structure of two individual CB isoforms (CBa2, CBc), and one isoform in a crotoxin (CA2CBb) complex, have been previously reported. This study concerns CBd, which by interaction with various protein targets exhibits many physiological or pharmacological functions. It binds with high affinity to presynaptic receptors showing neurotoxicity, but also interacts with human coagulation factor Xa (hFXa), exhibiting anticoagulant effect, and acts as a positive allosteric modulator and corrector of mutated chloride channel, cystic fibrosis transmembrane conductance regulator (CFTR), implicated in cystic fibrosis. Thus, CBd represents a novel family of agents that have potential in identifying new drug leads related to anticoagulant and anti-cystic fibrosis function. We determined here the X-ray structure of CBd and compare it with the three other natural isoforms of CB. The structural role of specific amino acid variations between CB isoforms are analyzed and the structural framework of CB for interaction with protein targets is described.
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Affiliation(s)
- Dorota Nemecz
- Institut Pasteur, Récepteurs-Canaux, CNRS UMR 3571, Département de Neuroscience, 25, rue du Dr. Roux, F-75015 Paris, France; (D.N.); (M.O.); (M.R.)
- Biochemistry Department, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, 87-100 Torun, Poland
| | - Maciej Ostrowski
- Institut Pasteur, Récepteurs-Canaux, CNRS UMR 3571, Département de Neuroscience, 25, rue du Dr. Roux, F-75015 Paris, France; (D.N.); (M.O.); (M.R.)
- Biochemistry Department, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, 87-100 Torun, Poland
| | - Marc Ravatin
- Institut Pasteur, Récepteurs-Canaux, CNRS UMR 3571, Département de Neuroscience, 25, rue du Dr. Roux, F-75015 Paris, France; (D.N.); (M.O.); (M.R.)
- Sanofi R&D, Integrated Drug Discovery-High Content Biology, 94400 Vitry-sur-Seine, France
| | - Frederick Saul
- Institut Pasteur, Plateforme de Cristallographie-C2RT, CNRS UMR 3528, 75015 Paris, France;
| | - Grazyna Faure
- Institut Pasteur, Récepteurs-Canaux, CNRS UMR 3571, Département de Neuroscience, 25, rue du Dr. Roux, F-75015 Paris, France; (D.N.); (M.O.); (M.R.)
- Correspondence: ; Tel.: +33-14-568-86-86; Fax: +33-14-568-88-36
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D Vaz de Melo P, de Almeida Lima S, Araújo P, Medina Santos R, Gonzalez E, Alves Belo A, Machado-de-Ávila RA, Costal-Oliveira F, T Soccol V, Guerra-Duarte C, Rezende L, Chavez-Olortegui C. Immunoprotection against lethal effects of Crotalus durissus snake venom elicited by synthetic epitopes trapped in liposomes. Int J Biol Macromol 2020; 161:299-307. [PMID: 32464201 DOI: 10.1016/j.ijbiomac.2020.05.171] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/19/2020] [Accepted: 05/21/2020] [Indexed: 10/24/2022]
Abstract
Snakebites caused by Crotalus genus are the second most frequent in Brazil. Crotoxin is a beta-neurotoxin responsible for the main envenomation effects of Crotalus biting, while crotamine immobilizes the animal hind limbs, contributing to prey immobilization and to envenoming symptoms. As crotoxin and crotamine represent about 90% of Crotalus venom dry weight, these toxins are of great importance for antivenom therapy. In this sense, knowledge regarding the antigenicity/immunogenicity at the molecular level of these toxins can provide valuable information for the improvement of specific antivenoms. Therefore, the aims of this study are the identification of the B-cell epitopes from crotoxin and crotamine; and the characterization of the neutralizing potency of antibodies directed against the corresponding synthetic epitopes defined in the current study. Linear B-cell epitopes were identified using the Spot Synthesis technique probed with specific anti-C. d. terrificus venom horse IgG. One epitope of crotamine (F12PKEKICLPPSSDFGKMDCRW32) and three of crotoxin (L10LVGVEGHLLQFNKMIKFETR30; Y43CGWGGRGRPKDATDRCCFVH63 and T118YKYGYMFYPDSRCRGPSETC138) were identified. After synthesis in their soluble form, the peptides mixture correspondent to the mapped epitopes was entrapped in liposomes and used as immunogens for antibody production in rabbits. Anti-synthetic peptide antibodies were able to protect mice from the lethal activity of C. d. terrificus venom.
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Affiliation(s)
- Patrícia D Vaz de Melo
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil; Labtest Diagnostica SA, Minas Gerais, Brazil
| | - Sabrina de Almeida Lima
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Priscila Araújo
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Raíssa Medina Santos
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Edgar Gonzalez
- Icahn School of Medicine at Mount Sinai, NY, United States of America
| | - Andreza Alves Belo
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil; Labtest Diagnostica SA, Minas Gerais, Brazil
| | | | - Fernanda Costal-Oliveira
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | | | - Clara Guerra-Duarte
- Centro de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias, 30510-010 Belo Horizonte, MG, Brazil
| | | | - Carlos Chavez-Olortegui
- Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP: 31270-901 Belo Horizonte, Minas Gerais, Brazil.
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Saavedra SL, Acosta G, Ávila L, Giudicessi SL, Camperi SA, Albericio F, Cascone O, Martínez Ceron MC. Use of a phosphopeptide as a ligand to purify phospholipase A 2 from the venom of Crotalus durisuss terrificus by affinity chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2020; 1146:122070. [PMID: 32361466 DOI: 10.1016/j.jchromb.2020.122070] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 03/06/2020] [Accepted: 03/14/2020] [Indexed: 12/19/2022]
Abstract
The venom of Crotalus durissus terrificus (Cdt) is a source of a wide variety of toxins, some of them with interesting pharmacological applications. Of these toxins, the phospholipase A2 (PLA2) subunit of crotoxin (Ctx) has been studied for its potential as an antiviral and antibacterial agent. Peptides have proven useful ligands for the purification of numerous molecules, including antibodies, toxins, enzymes and other proteins. Here, we sought to use a phosphopeptide (P-Lys) as a ligand for PLA2 purification. P-Lys was synthesized in solid phase on Rink-Amide-ChemMatrix resin, immobilized on NHS-agarose, and then evaluated as a chromatographic matrix. Under the best conditions, total protein adsorption reached 39% and only the eluate fraction presented PLA2 activity. Analysis of the eluate by SDS-PAGE showed three bands, one corresponding to the molecular weight of PLA2 (14 kDa). Said bands were analyzed by mass spectrometry and identified as PLA2 and its multimers. The final product showed a purity of over 90%. In addition, slightly changing the process conditions also allowed the isolation of crotamine.
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Affiliation(s)
- Soledad L Saavedra
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biotecnología, Junín 956, 1113 Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Nanobiotecnología (NANOBIOTEC), Junín 956, 1113 Buenos Aires, Argentina
| | - Gerardo Acosta
- Department of Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain; CIBER-BBN, Networking Centre on Bioengineering, Biomaterials and Nanomedicine, University of Barcelona, 08028 Barcelona, Spain
| | - Lucía Ávila
- Instituto Nacional de Producción de Biológicos, ANLIS Malbrán, Av. Vélez Sársfield 563, 1282 Buenos Aires, Argentina
| | - Silvana L Giudicessi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biotecnología, Junín 956, 1113 Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Nanobiotecnología (NANOBIOTEC), Junín 956, 1113 Buenos Aires, Argentina
| | - Silvia A Camperi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biotecnología, Junín 956, 1113 Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Nanobiotecnología (NANOBIOTEC), Junín 956, 1113 Buenos Aires, Argentina
| | - Fernando Albericio
- Department of Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain; CIBER-BBN, Networking Centre on Bioengineering, Biomaterials and Nanomedicine, University of Barcelona, 08028 Barcelona, Spain; School of Chemistry & Physics, University of Kwazulu-Natal, Durban 4001, South Africa
| | - Osvaldo Cascone
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biotecnología, Junín 956, 1113 Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Nanobiotecnología (NANOBIOTEC), Junín 956, 1113 Buenos Aires, Argentina; Instituto Nacional de Producción de Biológicos, ANLIS Malbrán, Av. Vélez Sársfield 563, 1282 Buenos Aires, Argentina
| | - María C Martínez Ceron
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biotecnología, Junín 956, 1113 Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Nanobiotecnología (NANOBIOTEC), Junín 956, 1113 Buenos Aires, Argentina.
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11
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Bioaffinity Fishing Procedure Using Secretory Phospholipase A2 for Screening for Bioactive Components: Modulation of Pharmacological Effect Induced by sPLA2 from Crotalus durissus terrificus by Hispidulin from Moquiniastrum floribundum. Molecules 2020; 25:molecules25020282. [PMID: 31936688 PMCID: PMC7024236 DOI: 10.3390/molecules25020282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/02/2020] [Accepted: 01/06/2020] [Indexed: 12/23/2022] Open
Abstract
Bioaffinity capturing of molecules allows the discovery of bioactive compounds and decreases the need for various stages in the natural compound isolation process. Despite the high selectivity of this technique, the screening and identification methodology depends on the presence of a protein to capture potential ligands. However, some proteins, such as snake secretory phospholipase A2 (sPLA2), have never been investigated using this approach. The purpose of this study was to evaluate the use of a new method for screening natural compounds using a bioaffinity-guided ultrafiltration method on Crotalus durissus terrificus sPLA2 followed by HPLC-MS to identify the compounds, and this method could be used to discover new anti-inflammatory compounds from the various organisms originating from biodiversity. Different extracts were selected to evaluate their ability to inhibit sPLA2 activity. The extracts were incubated with sPLA2 and the resulting mixture was ultrafiltrated to elute unbound components. The resulting compounds were identified by HPLC-MS. We identified hispidulin as one of the components present in the Moquiniastrum floribundum leaf and evaluated the ability of this isolated compound to neutralize the inflammatory activity of sPLA2 from Crotalus durissus terrificus.
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Luzuriaga-Quichimbo CX, Blanco-Salas J, Muñoz-Centeno LM, Peláez R, Cerón-Martínez CE, Ruiz-Téllez T. In Silico Molecular Studies of Antiophidic Properties of the Amazonian Tree Cordia nodosa Lam. Molecules 2019; 24:E4160. [PMID: 31744153 PMCID: PMC6891429 DOI: 10.3390/molecules24224160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/08/2019] [Accepted: 11/11/2019] [Indexed: 11/29/2022] Open
Abstract
We carried out surveys on the use of Cordia nodosa Lam. in the jungles of Bobonaza (Ecuador). We documented this knowledge to prevent its loss under the Framework of the Convention on Biological Diversity and the Nagoya Protocol. We conducted bibliographic research and identified quercetrin as a significant bioactive molecule. We studied its in silico biological activity. The selected methodology was virtual docking experiments with the proteins responsible for the venomous action of snakes. The molecular structures of quercetrin and 21 selected toxins underwent corresponding tests with SwissDock and Chimera software. The results point to support its antiophidic use. They show reasonable geometries and a binding free energy of -7 to -10.03 kcal/mol. The most favorable values were obtained for the venom of the Asian snake Naja atra (5Z2G, -10.03 kcal/mol). Good results were also obtained from the venom of the Latin American Bothrops pirajai (3CYL, -9.71 kcal/mol) and that of Ecuadorian Bothrops asper snakes (5TFV, -9.47 kcal/mol) and Bothrops atrox (5TS5, -9.49 kcal/mol). In the 5Z2G and 5TS5 L-amino acid oxidases, quercetrin binds in a pocket adjacent to the FAD cofactor, while in the myotoxic homologues of PLA2, 3CYL and 5TFV, it joins in the hydrophobic channel formed when oligomerizing, in the first one similar to α-tocopherol. This study presents a case demonstration of the potential of bioinformatic tools in the validation process of ethnobotanical phytopharmaceuticals and how in silico methods are becoming increasingly useful for sustainable drug discovery.
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Affiliation(s)
| | - José Blanco-Salas
- Department, Faculty of Sciences, University of Extremadura, 06006 Badajoz, Spain;
| | | | - Rafael Peláez
- Departament of Pharmaceutical Sciences, Organic Chemistry, University of Salamanca, 37008 Salamanca, Spain;
| | | | - Trinidad Ruiz-Téllez
- Department, Faculty of Sciences, University of Extremadura, 06006 Badajoz, Spain;
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13
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Sousa ID, Barbosa AR, Salvador GH, Frihling BE, Santa-Rita PH, Soares AM, Pessôa HL, Marchi-Salvador DP. Secondary hemostasis studies of crude venom and isolated proteins from the snake Crotalus durissus terrificus. Int J Biol Macromol 2019; 131:127-133. [DOI: 10.1016/j.ijbiomac.2019.03.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 03/09/2019] [Accepted: 03/09/2019] [Indexed: 10/27/2022]
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14
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Fortes-Dias CL, Fernandes CAH, Ortolani PL, Campos PC, Melo LA, Felicori LF, Fontes MRM. Identification, description and structural analysis of beta phospholipase A 2 inhibitors (sbβPLIs) from Latin American pit vipers indicate a binding site region for basic snake venom phospholipases A 2. Toxicon X 2019; 2:100009. [PMID: 32550566 PMCID: PMC7286088 DOI: 10.1016/j.toxcx.2019.100009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/04/2019] [Accepted: 02/13/2019] [Indexed: 11/17/2022] Open
Abstract
Several snake species possess, in their circulating blood, endogenous PLA2 inhibitors (sbPLIs) with the primary function of natural protection against toxic enzymes from homologous and heterologous venoms. Among the three structural classes of sbPLIs – named α, β, and γ − the β class (sbβPLIs) is the least known with only four identified sequences, so far. The last class of inhibitors encompass molecules with leucine rich repeats (LRRs) motifs containing repeating amino acid segments. In the present study, we identified and characterized putative sbβPLIs from the liver and venom glands of six Latin American pit vipers belonging to Bothrops and Crotalus genera. The inhibitor from Crotalus durissus terrificus snakes (CdtsbβPLI) was chosen as a reference for the construction of the first in silico structural model for this class of inhibitors, using molecular modeling and molecular dynamics simulations. Detailed analyses of the electrostatic surface of the CdtsbβPLI model and protein-protein docking with crotoxin B from homologous venoms predict the interacting surface between these proteins. Transcripts of phospholipases A2 inhibitors from the β-class (sbβPLIs) were identified in Latin American pit vipers. Structural features of sbβPLIs were compared and discussed, including their characteristic leucine-rich repeats (LRRs). One sbβPLI (CdtsbβPLI) was chosen for the in silico construction of the first structural model of a sbβPLI. A possible mechanism of interaction between sbβPLIs and basic snake venom PLA2s was suggested. Docking predictions between CdtsbβPLI and crotoxin B highlighted the amino acids residues at the interaction surfaces.
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Affiliation(s)
- Consuelo Latorre Fortes-Dias
- Serviço de Enzimologia, Diretoria de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias (FUNED), Belo Horizonte, MG, Brazil
| | - Carlos Alexandre H Fernandes
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil.,Departamento de Genética, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil
| | - Paula Ladeira Ortolani
- Serviço de Enzimologia, Diretoria de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias (FUNED), Belo Horizonte, MG, Brazil
| | - Patrícia Cota Campos
- Serviço de Enzimologia, Diretoria de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias (FUNED), Belo Horizonte, MG, Brazil
| | - L A Melo
- Serviço de Enzimologia, Diretoria de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias (FUNED), Belo Horizonte, MG, Brazil
| | - Liza Figueiredo Felicori
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| | - Marcos Roberto M Fontes
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, Brazil
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15
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Whittington AC, Mason AJ, Rokyta DR. A Single Mutation Unlocks Cascading Exaptations in the Origin of a Potent Pitviper Neurotoxin. Mol Biol Evol 2019; 35:887-898. [PMID: 29329419 DOI: 10.1093/molbev/msx334] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Evolutionary innovations and complex phenotypes seemingly require an improbable amount of genetic change to evolve. Rattlesnakes display two dramatically different venom phenotypes. Type I venoms are hemorrhagic with low systemic toxicity and high expression of tissue-destroying snake venom metalloproteinases. Type II venoms are highly neurotoxic and lack snake venom metalloproteinase expression and associated hemorrhagic activity. This dichotomy hinges on Mojave toxin (MTx), a phospholipase A2 (PLA2) based β-neurotoxin expressed in Type II venoms. MTx is comprised of a nontoxic acidic subunit that undergoes extensive proteolytic processing and allosterically regulates activity of a neurotoxic basic subunit. Evolution of the acidic subunit presents an evolutionary challenge because the need for high expression of a nontoxic venom component and the proteolytic machinery required for processing suggests genetic changes of seemingly little immediate benefit to fitness. We showed that MTx evolved through a cascading series of exaptations unlocked by a single nucleotide change. The evolution of one new cleavage site in the acidic subunit unmasked buried cleavage sites already present in ancestral PLA2s, enabling proteolytic processing. Snake venom serine proteases, already present in the venom to disrupt prey hemostasis, possess the requisite specificities for MTx acidic subunit proteolysis. The dimerization interface between MTx subunits evolved by exploiting a latent, but masked, hydrophobic interaction between ancestral PLA2s. The evolution of MTx through exaptation of existing functional and structural features suggests complex phenotypes that depend on evolutionary innovations can arise from minimal genetic change enabled by prior evolution.
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Affiliation(s)
- A Carl Whittington
- Department of Biological Science, Florida State University, Tallahassee, FL
| | - Andrew J Mason
- Department of Biology, University of Central Florida, Orlando, FL
- Department of Biological Sciences, Clemson University, Clemson, SC
| | - Darin R Rokyta
- Department of Biological Science, Florida State University, Tallahassee, FL
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16
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Muller SP, Silva VAO, Silvestrini AVP, de Macedo LH, Caetano GF, Reis RM, Mazzi MV. Crotoxin from Crotalus durissus terrificus venom: In vitro cytotoxic activity of a heterodimeric phospholipase A2 on human cancer-derived cell lines. Toxicon 2018; 156:13-22. [DOI: 10.1016/j.toxicon.2018.10.306] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 10/03/2018] [Accepted: 10/29/2018] [Indexed: 12/15/2022]
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17
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Dietz JDC, Almeida DAD, Cintra LC, Oliveira BFRD, Magalhães MR, Jesuíno RSA. EVALUATION OF THE ANTIBACTERIAL ACTIVITY OF Crotalus durissus terrificus CRUDE VENOM. CIÊNCIA ANIMAL BRASILEIRA 2018. [DOI: 10.1590/1809-6891v19e-51322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Abstract Snake venoms are recognized as a promising source of pharmacologically active substances and are potentially useful for the development of new antimicrobial drugs. This study aimed to investigate the antimicrobial activity of the venom from the rattlesnake Crotalus durissus terrificus against several bacteria. Antibacterial activity was determined by using the plate microdilution method and the activity on the bacterial envelope structure was screened by using the crystal violet assay. The proteins in crude venom were separated by electrophoresis and characterized regarding their proteolytic activity. C. d. terrificus venom exhibited antimicrobial action against gram-positive and gram-negative bacteria. MIC values were defined for Pseudomonas aeruginosa ATCC 27853 (62.5 µg/mL), Staphylococcus aureus ATCC 25923 (125 µg/mL), and Micrococcus luteus ATCC 9341 (≤500 µg/mL). For Salmonella enterica serovar typhimurium ATCC 14028 and Corynebacterium glutamicum ATCC 13032, the decrease in bacterial growth was not detected visually, but was statistically significant. The crystal violet assay demonstrated that the crude venom increased bacterial cell permeability and the secreted protein profile agreed with previous reports. The results suggest that the proteins with lytic activity against bacteria in C. d. terrificus venom deserve further characterization as they may offer reinforcements to the weak therapeutic arsenal used to fight microbial multidrug resistance.
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18
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Camelid Single-Domain Antibodies (VHHs) against Crotoxin: A Basis for Developing Modular Building Blocks for the Enhancement of Treatment or Diagnosis of Crotalic Envenoming. Toxins (Basel) 2018; 10:toxins10040142. [PMID: 29596324 PMCID: PMC5923308 DOI: 10.3390/toxins10040142] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/11/2018] [Accepted: 03/16/2018] [Indexed: 12/15/2022] Open
Abstract
Toxic effects triggered by crotalic envenoming are mainly related to crotoxin (CTX), composed of a phospholipase A2 (CB) and a subunit with no toxic activity (CA). Camelids produce immunoglobulins G devoid of light chains, in which the antigen recognition domain is called VHH. Given their unique characteristics, VHHs were selected using Phage Display against CTX from Crotalus durissus terrificus. After three rounds of biopanning, four sequence profiles for CB (KF498602, KF498603, KF498604, and KF498605) and one for CA (KF498606) were revealed. All clones presented the VHH hallmark in FR2 and a long CDR3, with the exception of KF498606. After expressing pET22b-VHHs in E. coli, approximately 2 to 6 mg of protein per liter of culture were obtained. When tested for cross-reactivity, VHHs presented specificity for the Crotalus genus and were capable of recognizing CB through Western blot. KF498602 and KF498604 showed thermostability, and displayed affinity constants for CTX in the micro or nanomolar range. They inhibited in vitro CTX PLA2 activity, and CB cytotoxicity. Furthermore, KF498604 inhibited the CTX-induced myotoxicity in mice by 78.8%. Molecular docking revealed that KF498604 interacts with the CA–CB interface of CTX, seeming to block substrate access. Selected VHHs may be alternatives for the crotalic envenoming treatment.
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19
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Secreted Phospholipases A₂ from Animal Venoms in Pain and Analgesia. Toxins (Basel) 2017; 9:toxins9120406. [PMID: 29311537 PMCID: PMC5744126 DOI: 10.3390/toxins9120406] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/13/2017] [Accepted: 12/16/2017] [Indexed: 12/20/2022] Open
Abstract
Animal venoms comprise a complex mixture of components that affect several biological systems. Based on the high selectivity for their molecular targets, these components are also a rich source of potential therapeutic agents. Among the main components of animal venoms are the secreted phospholipases A2 (sPLA2s). These PLA2 belong to distinct PLA2s groups. For example, snake venom sPLA2s from Elapidae and Viperidae families, the most important families when considering envenomation, belong, respectively, to the IA and IIA/IIB groups, whereas bee venom PLA2 belongs to group III of sPLA2s. It is well known that PLA2, due to its hydrolytic activity on phospholipids, takes part in many pathophysiological processes, including inflammation and pain. Therefore, secreted PLA2s obtained from animal venoms have been widely used as tools to (a) modulate inflammation and pain, uncovering molecular targets that are implicated in the control of inflammatory (including painful) and neurodegenerative diseases; (b) shed light on the pathophysiology of inflammation and pain observed in human envenomation by poisonous animals; and, (c) characterize molecular mechanisms involved in inflammatory diseases. The present review summarizes the knowledge on the nociceptive and antinociceptive actions of sPLA2s from animal venoms, particularly snake venoms.
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Neuromuscular paralysis by the basic phospholipase A 2 subunit of crotoxin from Crotalus durissus terrificus snake venom needs its acid chaperone to concurrently inhibit acetylcholine release and produce muscle blockage. Toxicol Appl Pharmacol 2017; 334:8-17. [DOI: 10.1016/j.taap.2017.08.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/10/2017] [Accepted: 08/30/2017] [Indexed: 12/20/2022]
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21
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Sales TA, Marcussi S, da Cunha EFF, Kuca K, Ramalho TC. Can Inhibitors of Snake Venom Phospholipases A₂ Lead to New Insights into Anti-Inflammatory Therapy in Humans? A Theoretical Study. Toxins (Basel) 2017; 9:E341. [PMID: 29068410 PMCID: PMC5705956 DOI: 10.3390/toxins9110341] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 10/20/2017] [Accepted: 10/21/2017] [Indexed: 11/16/2022] Open
Abstract
Human phospholipase A₂ (hPLA₂) of the IIA group (HGIIA) catalyzes the hydrolysis of membrane phospholipids, producing arachidonic acid and originating potent inflammatory mediators. Therefore, molecules that can inhibit this enzyme are a source of potential anti-inflammatory drugs, with different action mechanisms of known anti-inflammatory agents. For the study and development of new anti-inflammatory drugs with this action mechanism, snake venom PLA₂ (svPLA₂) can be employed, since the svPLA₂ has high similarity with the human PLA₂ HGIIA. Despite the high similarity between these secretory PLA₂s, it is still not clear if these toxins can really be employed as an experimental model to predict the interactions that occur with the human PLA₂ HGIIA and its inhibitors. Thus, the present study aims to compare and evaluate, by means of theoretical calculations, docking and molecular dynamics simulations, as well as experimental studies, the interactions of human PLA₂ HGIIA and two svPLA₂s,Bothrops toxin II and Crotoxin B (BthTX-II and CB, respectively). Our theoretical findings corroborate experimental data and point out that the human PLA₂ HGIIA and svPLA₂ BthTX-II lead to similar interactions with the studied compounds. From our results, the svPLA₂ BthTX-II can be used as an experimental model for the development of anti-inflammatory drugs for therapy in humans.
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Affiliation(s)
- Thaís A Sales
- Department of Chemistry, Federal University of Lavras, P.O. Box 3037, 37200-000 Lavras, MG, Brazil.
| | - Silvana Marcussi
- Department of Chemistry, Federal University of Lavras, P.O. Box 3037, 37200-000 Lavras, MG, Brazil.
| | - Elaine F F da Cunha
- Department of Chemistry, Federal University of Lavras, P.O. Box 3037, 37200-000 Lavras, MG, Brazil.
| | - Kamil Kuca
- Biomedical Research Center, University Hospital Hradec Kralove, 500 05 Hradec Kralove, Czech Republic.
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic.
| | - Teodorico C Ramalho
- Department of Chemistry, Federal University of Lavras, P.O. Box 3037, 37200-000 Lavras, MG, Brazil.
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic.
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22
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Xavier CV, da S Setúbal S, Lacouth-Silva F, Pontes AS, Nery NM, de Castro OB, Fernandes CFC, Soares AM, Fortes-Dias CL, Zuliani JP. Phospholipase A 2 Inhibitor from Crotalus durissus terrificus rattlesnake: Effects on human peripheral blood mononuclear cells and human neutrophils cells. Int J Biol Macromol 2017; 105:1117-1125. [PMID: 28743568 DOI: 10.1016/j.ijbiomac.2017.07.140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 12/20/2022]
Abstract
Crotalus Neutralizing Factor (CNF) is an inhibitor of phospholipase A2 (PLA2), present in the blood plasma of Crotalus durissus terrificus snake. This inhibitor neutralizes the lethal and enzymatic activity of crotoxin, the main neurotoxin from this venom. In this study, we investigated the effects of CNF on the functionality of human peripheral blood mononuclear cells (PBMCs) and human neutrophils. The following parameters were evaluated: viability and proliferation, chemotaxis, cytokines and LTB4 production, cytosolic PLA2s activity, myeloperoxidase (MPO) and superoxide anion (O2-) production. CNF showed no toxicity on PBMCs or neutrophils, and acts by stimulating the release of TNF-α and LTB4, but neither stimulates IL-10 and IL-2 nor affects PBMCs proliferation and O2- release. In neutrophils, CNF induces chemotaxis but does not induce the release of both MPO and O2-. However, it induces LTB4 and IL-8 production. These data show the influence of CNF on PBMCs' function by inducing TNF-α and LTB4 production, and on neutrophils, by stimulating chemotaxis and LTB4 production, via cytosolic PLA2 activity, and IL-8 release. The inflammatory profile produced by CNF is shown for the first time. Our present results suggest that CNF has a role in activation of leukocytes and exert proinflammatory effects on these cell.
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Affiliation(s)
- Caroline V Xavier
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Sulamita da S Setúbal
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Fabianne Lacouth-Silva
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Adriana S Pontes
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Neriane M Nery
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Onassis Boeri de Castro
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Carla F C Fernandes
- Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil; Centro de Estudos de Biomoléculas Aplicadas à Saúde (CEBio), Fundação Oswaldo Cruz, FIOCRUZ Rondônia e Departamento de Medicina, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil; Centro de Pesquisa em Medicina Tropical (CEPEM), Porto Velho, RO, Brazil
| | - Andreimar M Soares
- Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil; Centro de Estudos de Biomoléculas Aplicadas à Saúde (CEBio), Fundação Oswaldo Cruz, FIOCRUZ Rondônia e Departamento de Medicina, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil
| | - Consuelo L Fortes-Dias
- Diretoria de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias (FUNED), Belo Horizonte, MG, Brazil
| | - Juliana P Zuliani
- Laboratório de Imunologia Celular Aplicada à Saúde, Fundação Oswaldo Cruz, FIOCRUZ Rondônia, Porto Velho, RO, Brazil; Programa de Pós-Graduação em Biologia Experimental, PGBIOEXP, Núcleo de Saúde, NUSAU, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil; Centro de Estudos de Biomoléculas Aplicadas à Saúde (CEBio), Fundação Oswaldo Cruz, FIOCRUZ Rondônia e Departamento de Medicina, Universidade Federal de Rondônia, UNIR, Porto Velho, RO, Brazil.
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Fernandes CAH, Pazin WM, Dreyer TR, Bicev RN, Cavalcante WLG, Fortes-Dias CL, Ito AS, Oliveira CLP, Fernandez RM, Fontes MRM. Biophysical studies suggest a new structural arrangement of crotoxin and provide insights into its toxic mechanism. Sci Rep 2017; 7:43885. [PMID: 28256632 PMCID: PMC5335569 DOI: 10.1038/srep43885] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 01/31/2017] [Indexed: 11/19/2022] Open
Abstract
Crotoxin (CTX) is the main neurotoxin found in Crotalus durissus rattlesnake venoms being composed by a nontoxic and non-enzymatic component (CA) and a toxic phospholipase A2 (CB). Previous crystallographic structures of CTX and CB provided relevant insights: (i) CTX structure showed a 1:1 molecular ratio between CA and CB, presenting three tryptophan residues in the CA/CB interface and one exposed to solvent; (ii) CB structure displayed a tetrameric conformation. This study aims to provide further information on the CTX mechanism of action by several biophysical methods. Our data show that isolated CB can in fact form tetramers in solution; however, these tetramers can be dissociated by CA titration. Furthermore, CTX exhibits a strong reduction in fluorescence intensity and lifetime compared with isolated CA and CB, suggesting that all tryptophan residues in CTX may be hidden by the CA/CB interface. By companying spectroscopy fluorescence and SAXS data, we obtained a new structural model for the CTX heterodimer in which all tryptophans are located in the interface, and the N-terminal region of CB is largely exposed to the solvent. Based on this model, we propose a toxic mechanism of action for CTX, involving the interaction of N-terminal region of CB with the target before CA dissociation.
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Affiliation(s)
- Carlos A. H. Fernandes
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu-SP, Brazil
| | - Wallance M. Pazin
- Departamento de Física, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, USP, Ribeirão Preto-SP, Brazil
| | - Thiago R. Dreyer
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu-SP, Brazil
| | - Renata N. Bicev
- Departamento de Física Experimental, Instituto de Física, Universidade de São Paulo – USP, São Paulo, SP, Brazil
| | - Walter L. G. Cavalcante
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu-SP, Brazil
- Departamento de Farmacologia, Instituto de Ciências Biológicas, UFMG, Belo Horizonte, MG, Brazil
| | - Consuelo L. Fortes-Dias
- Diretoria de Pesquisa e Desenvolvimento, Fundação Ezequiel Dias (FUNED), Belo Horizonte, MG, Brazil
| | - Amando S. Ito
- Departamento de Física, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, USP, Ribeirão Preto-SP, Brazil
| | - Cristiano L. P. Oliveira
- Departamento de Física Experimental, Instituto de Física, Universidade de São Paulo – USP, São Paulo, SP, Brazil
| | - Roberto Morato Fernandez
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu-SP, Brazil
| | - Marcos R. M. Fontes
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu-SP, Brazil
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Faure G, Porowinska D, Saul F. Crotoxin from Crotalus durissus terrificus and Crotoxin-Related Proteins: Structure and Function Relationship. TOXINS AND DRUG DISCOVERY 2017. [DOI: 10.1007/978-94-007-6452-1_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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25
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First crotoxin-like phospholipase A2 complex from a New World non-rattlesnake species: Nigroviriditoxin, from the arboreal Neotropical snake Bothriechis nigroviridis. Toxicon 2015; 93:144-54. [DOI: 10.1016/j.toxicon.2014.11.235] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 11/21/2014] [Accepted: 11/27/2014] [Indexed: 01/19/2023]
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26
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Muller VD, Soares RO, dos Santos-Junior NN, Trabuco AC, Cintra AC, Figueiredo LT, Caliri A, Sampaio SV, Aquino VH. Phospholipase A2 isolated from the venom of Crotalus durissus terrificus inactivates dengue virus and other enveloped viruses by disrupting the viral envelope. PLoS One 2014; 9:e112351. [PMID: 25383618 PMCID: PMC4226559 DOI: 10.1371/journal.pone.0112351] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 10/05/2014] [Indexed: 11/18/2022] Open
Abstract
The Flaviviridae family includes several virus pathogens associated with human diseases worldwide. Within this family, Dengue virus is the most serious threat to public health, especially in tropical and sub-tropical regions of the world. Currently, there are no vaccines or specific antiviral drugs against Dengue virus or against most of the viruses of this family. Therefore, the development of vaccines and the discovery of therapeutic compounds against the medically most important flaviviruses remain a global public health priority. We previously showed that phospholipase A2 isolated from the venom of Crotalus durissus terrificus was able to inhibit Dengue virus and Yellow fever virus infection in Vero cells. Here, we present evidence that phospholipase A2 has a direct effect on Dengue virus particles, inducing a partial exposure of genomic RNA, which strongly suggests inhibition via the cleavage of glycerophospholipids at the virus lipid bilayer envelope. This cleavage might induce a disruption of the lipid bilayer that causes a destabilization of the E proteins on the virus surface, resulting in inactivation. We show by computational analysis that phospholipase A2 might gain access to the Dengue virus lipid bilayer through the pores found on each of the twenty 3-fold vertices of the E protein shell on the virus surface. In addition, phospholipase A2 is able to inactivate other enveloped viruses, highlighting its potential as a natural product lead for developing broad-spectrum antiviral drugs.
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Affiliation(s)
- Vanessa Danielle Muller
- Laboratório de Virologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Ricardo Oliveira Soares
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Nilton Nascimento dos Santos-Junior
- Laboratório de Virologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Amanda Cristina Trabuco
- Laboratório de Virologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Adelia Cristina Cintra
- Laboratório de Toxinologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Luiz Tadeu Figueiredo
- Centro de Pesquisa em Virologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Antonio Caliri
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Suely Vilela Sampaio
- Laboratório de Toxinologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
| | - Victor Hugo Aquino
- Laboratório de Virologia, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brasil
- * E-mail:
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Crotoxin from Crotalus durissus terrificus snake venom induces the release of glutamate from cerebrocortical synaptosomes via N and P/Q calcium channels. Toxicon 2014; 85:5-16. [DOI: 10.1016/j.toxicon.2014.04.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 04/01/2014] [Accepted: 04/09/2014] [Indexed: 11/23/2022]
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Kuhle K, Krausze J, Curth U, Rössle M, Heuner K, Lang C, Flieger A. Oligomerization inhibits Legionella pneumophila PlaB phospholipase A activity. J Biol Chem 2014; 289:18657-66. [PMID: 24811180 DOI: 10.1074/jbc.m114.573196] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The intracellularly replicating lung pathogen Legionella pneumophila consists of an extraordinary variety of phospholipases, including at least 15 different phospholipases A (PLA). Among them, PlaB, the first characterized member of a novel lipase family, is a hemolytic virulence factor that exhibits the most prominent PLA activity in L. pneumophila. We analyzed here protein oligomerization, the importance of oligomerization for activity, addressed further essential regions for activity within the PlaB C terminus, and the significance of PlaB-derived lipolytic activity for L. pneumophila intracellular replication. We determined by means of analytical ultracentrifugation and small angle x-ray scattering analysis that PlaB forms homodimers and homotetramers. The C-terminal 5, 10, or 15 amino acids, although the individual regions contributed to PLA activity, were not essential for protein tetramerization. Infection of mouse macrophages with L. pneumophila wild type, plaB knock-out mutant, and plaB complementing or various mutated plaB-harboring strains showed that catalytic activity of PlaB promotes intracellular replication. We observed that PlaB was most active in the lower nanomolar concentration range but not at or only at a low level at concentration above 0.1 μm where it exists in a dimer/tetramer equilibrium. We therefore conclude that PlaB is a virulence factor that, on the one hand, assembles in inactive tetramers at micromolar concentrations. On the other hand, oligomer dissociation at nanomolar concentrations activates PLA activity. Our data highlight the first example of concentration-dependent phospholipase inactivation by tetramerization, which may protect the bacterium from internal PLA activity, but enzyme dissociation may allow its activation after export.
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Affiliation(s)
- Katja Kuhle
- From the Robert Koch-Institut, 38855 Wernigerode
| | - Joern Krausze
- the Helmholtz Center for Infection Research, 38124 Braunschweig
| | - Ute Curth
- the Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover
| | - Manfred Rössle
- the European Molecular Biology Laboratory, 22603 Hamburg Branch, c/o DESY, Hamburg, and the Lübeck University of Applied Sciences, 23562 Lübeck, Germany
| | - Klaus Heuner
- From the Robert Koch-Institut, 38855 Wernigerode
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An evaluation of 3-rhamnosylquercetin, a glycosylated form of quercetin, against the myotoxic and edematogenic effects of sPLA 2 from Crotalus durissus terrificus. BIOMED RESEARCH INTERNATIONAL 2014; 2014:341270. [PMID: 24696848 PMCID: PMC3947839 DOI: 10.1155/2014/341270] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 12/09/2013] [Accepted: 12/09/2013] [Indexed: 12/14/2022]
Abstract
This paper shows the results of quercitrin effects on the structure and biological activity of secretory phospholipase (sPLA2) from Crotalus durissus terrificus, which is the main toxin involved in the pharmacological effects of this snake venom. According to our mass spectrometry and circular dichroism results, quercetin was able to promote a chemical modification of some amino acid residues and modify the secondary structure of C. d. terrificus sPLA2. Moreover, molecular docking studies showed that quercitrin can establish chemical interactions with some of the crucial amino acid residues involved in the enzymatic activity of the sPLA2, indicating that this flavonoid could also physically impair substrate molecule access to the catalytic site of the toxin. Additionally, in vitro and in vivo assays showed that the quercitrin strongly diminished the catalytic activity of the protein, altered its Vmax and Km values, and presented a more potent inhibition of essential pharmacological activities in the C. d. terrificus sPLA2, such as its myotoxicity and edematogenic effect, in comparison to quercetin. Thus, we concluded that the rhamnose group found in quercitrin is most likely essential to the antivenom activities of this flavonoid against C. d. terrificus sPLA2.
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30
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Ostrowski M, Žnidaršič PP, Raynal B, Saul F, Faure G. Human coagulation factor Xa prevents oligomerization of anti-coagulant phospholipases A2. TOXIN REV 2013. [DOI: 10.3109/15569543.2013.860170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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31
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Vieira LF, Magro AJ, Fernandes CA, de Souza BM, Cavalcante WL, Palma MS, Rosa JC, Fuly AL, Fontes MR, Gallacci M, Butzke DS, Calderon LA, Stábeli RG, Giglio JR, Soares AM. Biochemical, functional, structural and phylogenetic studies on Intercro, a new isoform phospholipase A2 from Crotalus durissus terrificus snake venom. Biochimie 2013; 95:2365-75. [DOI: 10.1016/j.biochi.2013.08.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 08/25/2013] [Indexed: 10/26/2022]
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32
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Snake venom PLA2s inhibitors isolated from Brazilian plants: synthetic and natural molecules. BIOMED RESEARCH INTERNATIONAL 2013; 2013:153045. [PMID: 24171158 PMCID: PMC3793501 DOI: 10.1155/2013/153045] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/19/2013] [Indexed: 01/21/2023]
Abstract
Ophidian envenomation is an important health problem in Brazil and other South American countries. In folk medicine, especially in developing countries, several vegetal species are employed for the treatment of snakebites in communities that lack prompt access to serum therapy. However, the identification and characterization of the effects of several new plants or their isolated compounds, which are able to inhibit the activities of snake venom, are extremely important and such studies are imperative. Snake venom contains several organic and inorganic compounds; phospholipases A2 (PLA2s) are one of the principal toxic components of venom. PLA2s display a wide variety of pharmacological activities, such as neurotoxicity, myotoxicity, cardiotoxicity, anticoagulant, hemorrhagic, and edema-inducing effects. PLA2 inhibition is of pharmacological and therapeutic interests as these enzymes are involved in several inflammatory diseases. This review describes the results of several studies of plant extracts and their isolated active principles, when used against crude snake venoms or their toxic fractions. Isolated inhibitors, such as steroids, terpenoids, and phenolic compounds, are able to inhibit PLA2s from different snake venoms. The design of specific inhibitors of PLA2s might help in the development of new pharmaceutical drugs, more specific antivenom, or even as alternative approaches for treating snakebites.
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Abstract
From the earliest work on regular arrays in negative stain, electron crystallography has contributed greatly to our understanding of the structure and function of biological macromolecules. The development of electron cryo-microscopy (cryo-EM) then lead to the first groundbreaking atomic models of the membrane proteins bacteriorhodopsin and light harvesting complex II within lipid bilayers. Key contributions towards cryo-EM and electron crystallography methods included specimen preparation and vitrification, liquid-helium cooling, data collection, and image processing. These methods are now applied almost routinely to both membrane and soluble proteins. Here we outline the advances and the breakthroughs that paved the way towards high-resolution structures by electron crystallography, both in terms of methods development and biological milestones.
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Abstract
Venoms and toxins are of significant interest due to their ability to cause a wide range of pathophysiological conditions that can potentially result in death. Despite their wide distribution among plants and animals, the biochemical pathways associated with these pathogenic agents remain largely unexplored. Impoverished and underdeveloped regions appear especially susceptible to increased incidence and severity due to poor socioeconomic conditions and lack of appropriate medical treatment infrastructure. To facilitate better management and treatment of envenomation victims, it is essential that the biochemical mechanisms of their action be elucidated. This review aims to characterize downstream envenomation mechanisms by addressing the major neuro-, cardio-, and hemotoxins as well as ion-channel toxins. Because of their use in folk and traditional medicine, the biochemistry behind venom therapy and possible implications on conventional medicine will also be addressed.
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35
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Faure G, Saul F. Crystallographic characterization of functional sites of crotoxin and ammodytoxin, potent β-neurotoxins from Viperidae venom. Toxicon 2012; 60:531-8. [PMID: 22683534 DOI: 10.1016/j.toxicon.2012.05.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 05/03/2012] [Accepted: 05/17/2012] [Indexed: 11/24/2022]
Abstract
This review will focus on a description of the three-dimensional structures of two β-neurotoxins, the monomeric PLA(2) ammodytoxin from Vipera ammodytes ammodytes, and heterodimeric crotoxin from Crotalus durissus terrificus, and a detailed structural analysis of their multiple functional sites. We have recently determined at high resolution the crystal structures of two natural isoforms of ammodytoxin (AtxA and AtxC) (Saul et al., 2010) which exhibit different toxicity profiles and different anticoagulant properties. Comparative structural analysis of these two PLA(2) isoforms, which differ only by two amino acid residues, allowed us to detect local conformational changes and delineate the role of critical residues in the anticoagulant and neurotoxic functions of these PLA(2) (Saul et al., 2010). We have also determined, at 1.35Å resolution, the crystal structure of heterodimeric crotoxin (Faure et al., 2011). The three-dimensional structure of crotoxin revealed details of the binding interface between its acidic (CA) and basic (CB) subunits and allowed us to identify key residues involved in the stability and toxicity of this potent heterodimeric β-neurotoxin (Faure et al., 2011). The precise spatial orientation of the three covalently linked polypeptide chains in the mature CA subunit complexed with CB helps us to understand the role played by critical residues of the CA subunit in the increased toxicity of the crotoxin complex. Since the CA subunit is a natural inhibitor of the catalytic and anticoagulant activities of CB, identification of the CA-CB binding interface describes residues involved in this inhibition. We propose future research directions based on knowledge of the recently reported 3D structures of crotoxin and ammodytoxin.
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Affiliation(s)
- Grazyna Faure
- Institut Pasteur, Récepteurs-Canaux, CNRS, URA 2182, Département de Neuroscience, 25, rue du Dr. Roux, F-75015 Paris, France.
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Pereañez JA, Gómez ID, Patiño AC. Relationship between the structure and the enzymatic activity of crotoxin complex and its phospholipase A2 subunit: an in silico approach. J Mol Graph Model 2012; 35:36-42. [PMID: 22481077 DOI: 10.1016/j.jmgm.2012.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Revised: 01/10/2012] [Accepted: 01/19/2012] [Indexed: 10/14/2022]
Abstract
Crotoxin, one of the major toxins of South American rattlesnake Crotalus durissus subspecies, is an heterodimeric complex composed of two distinct subunits: a basic phospholipase A(2) (PLA(2), CB) and an acidic nontoxic catalytically inactive protein, crotapotin (CA). It's well known that CB has a high enzymatic activity; however the molecular aspects that determine this fact remain unknown. In this study, an in silico approach was used to predict the CA structure by homology modeling, and the crotoxin structure by means of molecular docking. CA structure was built using the software Modeller taking Crotalus atrox PLA(2) (1PP2:R) as a template. Different criteria measured by Procheck, Verify 3D and ProSA were indicative of the reliability and the proper fold for the predicted structural model of CA. Then, a combination of this model and CB crystal structure was used to build the structure of crotoxin complex through rigid-body protein-protein docking. The crotoxin-3D model suggested that by means of hydrophobic and π-π stacking interactions, CA-Y24 and CA-F119 interact with CB-F24 and CB-F119, respectively. Those interactions could prevent the interfacial adsorption of the CB onto the lipid/water interface by blocking part of the interfacial binding surface of the PLA(2). This fact could explain the differences regarding to enzymatic activity between the crotoxin complex and CB. In addition, the crotoxin-3D model showed solvent-exposed regions of CA that could bind the receptor expressed in target cells.
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Affiliation(s)
- Jaime Andrés Pereañez
- Programa de Ofidismo/Escorpionismo, Universidad de Antioquia, A.A. 1226, Medellín, Colombia.
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Crystal Structure of Crotoxin Reveals Key Residues Involved in the Stability and Toxicity of This Potent Heterodimeric β-Neurotoxin. J Mol Biol 2011; 412:176-91. [DOI: 10.1016/j.jmb.2011.07.027] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/17/2011] [Accepted: 07/14/2011] [Indexed: 11/21/2022]
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38
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Kang TS, Georgieva D, Genov N, Murakami MT, Sinha M, Kumar RP, Kaur P, Kumar S, Dey S, Sharma S, Vrielink A, Betzel C, Takeda S, Arni RK, Singh TP, Kini RM. Enzymatic toxins from snake venom: structural characterization and mechanism of catalysis. FEBS J 2011; 278:4544-76. [PMID: 21470368 DOI: 10.1111/j.1742-4658.2011.08115.x] [Citation(s) in RCA: 185] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Snake venoms are cocktails of enzymes and non-enzymatic proteins used for both the immobilization and digestion of prey. The most common snake venom enzymes include acetylcholinesterases, l-amino acid oxidases, serine proteinases, metalloproteinases and phospholipases A(2) . Higher catalytic efficiency, thermal stability and resistance to proteolysis make these enzymes attractive models for biochemists, enzymologists and structural biologists. Here, we review the structures of these enzymes and describe their structure-based mechanisms of catalysis and inhibition. Some of the enzymes exist as protein complexes in the venom. Thus we also discuss the functional role of non-enzymatic subunits and the pharmacological effects of such protein complexes. The structures of inhibitor-enzyme complexes provide ideal platforms for the design of potent inhibitors which are useful in the development of prototypes and lead compounds with potential therapeutic applications.
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Affiliation(s)
- Tse Siang Kang
- Department of Pharmacy, National University of Singapore, Singapore
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Teixeira SS, Silveira LB, da Silva FMN, Marchi-Salvador DP, Silva FP, Izidoro LFM, Fuly AL, Juliano MA, dos Santos CR, Murakami MT, Sampaio SV, da Silva SL, Soares AM. Molecular characterization of an acidic phospholipase A(2) from Bothrops pirajai snake venom: synthetic C-terminal peptide identifies its antiplatelet region. Arch Toxicol 2011; 85:1219-33. [PMID: 21331602 DOI: 10.1007/s00204-011-0665-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Accepted: 01/31/2011] [Indexed: 11/27/2022]
Abstract
This paper describes a biochemical and pharmacological characterization of BpirPLA(2)-I, the first acidic Asp49-PLA(2) isolated from Bothrops pirajai. BpirPLA(2)-I caused hypotension in vivo, presented phospholipolytic activity upon artificial substrates and inhibitory effects on platelet aggregation in vitro. Moreover, a synthetic peptide of BpirPLA(2)-I, comprising residues of the C-terminal region, reproduced the antiplatelet activity of the intact protein. A cDNA fragment of 366 bp encompassing the mature form of BpirPLA(2)-I was cloned by reverse transcriptase-PCR of B. pirajai venom gland total RNA. A Bayesian phylogenetic analysis indicated that BpirPLA(2)-I forms a clade with other acid Asp49-PLA(2) enzymes from the Bothrops genus, which are characterized by the high catalytic activity associated with anticoagulant or hypotensive activity or both. Comparison of the electrostatic potential (EP) on the molecular surfaces calculated from a BpirPLA(2)-I homology model and from the crystallographic models of a group of close homologues revealed that the greatest number of charge inversions occurred on the face opposite to the active site entrance, particularly in the Ca(2+) ion binding loop. This observation suggests a possible relationship between the basic or acid character of PLA(2) enzymes and the functionality of the Ca(2+) ion binding loop.
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Affiliation(s)
- Sabrina S Teixeira
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, FCFRP-USP, Ribeirão Preto, SP, Brazil
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Santos ML, Toyama DO, Oliveira SCB, Cotrim CA, Diz-Filho EBS, Fagundes FHR, Soares VCG, Aparicio R, Toyama MH. Modulation of the pharmacological activities of secretory phospholipase A2 from Crotalus durissus cascavella induced by naringin. Molecules 2011; 16:738-61. [PMID: 21245808 PMCID: PMC6259155 DOI: 10.3390/molecules16010738] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 01/04/2011] [Accepted: 01/13/2011] [Indexed: 11/16/2022] Open
Abstract
In this work we have characterized the action of the naringin, a flavonoid found in grapefruit and known for its various pharmacological effects, which include antioxidant blood lipid lowering and anticancer activity, on the structure and biochemical activities of a secretory phospholipase A (sPLA2) from Crotalus durissus cascavella, an important protein involved in the releasinge of arachidonic acid in phospholipid membranes. sPLA2 was incubated with naringin (mol:mol) at 37 °C and a discrete reduction in the UV scanning signal and a modification of the circular dichroism spectra were observed after treatment with naringin, suggesting modifications of the secondary structure of the protein. This flavonoid was able to decrease enzymatic activity and some pharmacological effects, such as myonecrosis, platelet aggregation, and neurotoxic activity caused by sPLA2, however, the inflammatory effect was not affected by naringin. In addition, small angle X-ray scattering (SAXS) data were collected for sPLA2 and naringin-treated sPLA2 to evaluate possible modifications of the protein structure. These structural investigations have shown that sPLA2 is an elongated dimer in solution and after treatment with naringin a conformational change in the dimeric configuration was observed. Our results suggest that structural modification may be correlated with the loss of enzymatic activity and alterations in pharmacological properties.
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Affiliation(s)
- Marcelo L. Santos
- Laboratório de Biologia Estrutural e Cristalografia, Instituto de Química, UNICAMP, Campinas, São Paulo, Brazil
| | | | - Simone C. B. Oliveira
- Departmento de Bioquímica, Instituto de Biologia, UNICAMP, Campinas, São Paulo, Brazil
| | - Camila A. Cotrim
- Departmento de Bioquímica, Instituto de Biologia, UNICAMP, Campinas, São Paulo, Brazil
| | | | - Fábio H. R. Fagundes
- Departmento de Bioquímica, Instituto de Biologia, UNICAMP, Campinas, São Paulo, Brazil
| | - Veronica C. G. Soares
- Departmento de Bioquímica, Instituto de Biologia, UNICAMP, Campinas, São Paulo, Brazil
| | - Ricardo Aparicio
- Laboratório de Biologia Estrutural e Cristalografia, Instituto de Química, UNICAMP, Campinas, São Paulo, Brazil
| | - Marcos H. Toyama
- Laboratório de Macromoléculas Química, UNESP/CLP, São Vicente, São Paulo, Brazil
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dos Santos JI, Cintra-Francischinelli M, Borges RJ, Fernandes CAH, Pizzo P, Cintra ACO, Braz ASK, Soares AM, Fontes MRM. Structural, functional, and bioinformatics studies reveal a new snake venom homologue phospholipase A2class. Proteins 2010; 79:61-78. [DOI: 10.1002/prot.22858] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 07/22/2010] [Accepted: 08/13/2010] [Indexed: 11/09/2022]
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Sampaio SC, Hyslop S, Fontes MR, Prado-Franceschi J, Zambelli VO, Magro AJ, Brigatte P, Gutierrez VP, Cury Y. Crotoxin: Novel activities for a classic β-neurotoxin. Toxicon 2010; 55:1045-60. [DOI: 10.1016/j.toxicon.2010.01.011] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 12/17/2009] [Accepted: 01/09/2010] [Indexed: 10/19/2022]
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Fortes-Dias CL, Santos RMMD, Magro AJ, Fontes MRDM, Chávez-Olórtegui C, Granier C. Identification of continuous interaction sites in PLA2-based protein complexes by peptide arrays. Biochimie 2009; 91:1482-92. [DOI: 10.1016/j.biochi.2009.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Accepted: 08/27/2009] [Indexed: 10/20/2022]
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Salvador GHM, Fernandes CAH, Corrêa LC, Santos-Filho NA, Soares AM, Fontes MRM. Crystallization and preliminary X-ray diffraction analysis of crotoxin B from Crotalus durissus collilineatus venom. Acta Crystallogr Sect F Struct Biol Cryst Commun 2009; 65:1011-3. [PMID: 19851009 DOI: 10.1107/s1744309109032631] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 08/17/2009] [Indexed: 11/10/2022]
Abstract
Crotoxin B is a basic phospholipase A(2) found in the venom of several Crotalus durissus ssp. rattlesnakes and is one of the subunits that constitute crotoxin, the main component of the venom of these snakes. This heterodimeric toxin is related to important envenomation effects such as neurological disorders, myotoxicity and renal failure. Although crotoxin was first crystallized in 1938, the first structural data only became available in 2007 (for crotoxin B from C. durissus terrificus) and showed an ambiguous result for the biological assembly, which could be either dimeric or tetrameric. In this work, the crystallization, X-ray diffraction data collection at 2.2 A resolution and molecular-replacement solution of a dimeric complex formed by two crotoxin B isoforms from C. durissus collilineatus venom is presented.
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Affiliation(s)
- G H M Salvador
- Departamento de Física e Biofísica, Instituto de Biociências, UNESP, Distrito de Rubião Júnior, Caixa Postal 510, 18618-000 Botucatu-SP, Brazil
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Doley R, Kini RM. Protein complexes in snake venom. Cell Mol Life Sci 2009; 66:2851-71. [PMID: 19495561 PMCID: PMC11115964 DOI: 10.1007/s00018-009-0050-2] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 05/01/2009] [Accepted: 05/11/2009] [Indexed: 01/26/2023]
Abstract
Snake venom contains mixture of bioactive proteins and polypeptides. Most of these proteins and polypeptides exist as monomers, but some of them form complexes in the venom. These complexes exhibit much higher levels of pharmacological activity compared to individual components and play an important role in pathophysiological effects during envenomation. They are formed through covalent and/or non-covalent interactions. The subunits of the complexes are either identical (homodimers) or dissimilar (heterodimers; in some cases subunits belong to different families of proteins). The formation of complexes, at times, eliminates the non-specific binding and enhances the binding to the target molecule. On several occasions, it also leads to recognition of new targets as protein-protein interaction in complexes exposes the critical amino acid residues buried in the monomers. Here, we describe the structure and function of various protein complexes of snake venoms and their role in snake venom toxicity.
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Affiliation(s)
- R Doley
- Protein Science Laboratory, Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore.
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dos Santos JI, Soares AM, Fontes MR. Comparative structural studies on Lys49-phospholipases A2 from Bothrops genus reveal their myotoxic site. J Struct Biol 2009; 167:106-16. [DOI: 10.1016/j.jsb.2009.04.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 03/26/2009] [Accepted: 04/17/2009] [Indexed: 11/25/2022]
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Moreira V, Gutiérrez JM, Soares AM, Zamunér SR, Purgatto E, Teixeira CDFP. Secretory phospholipases A2 isolated from Bothrops asper and from Crotalus durissus terrificus snake venoms induce distinct mechanisms for biosynthesis of prostaglandins E2 and D2 and expression of cyclooxygenases. Toxicon 2008; 52:428-39. [DOI: 10.1016/j.toxicon.2008.06.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 06/10/2008] [Accepted: 06/13/2008] [Indexed: 11/30/2022]
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