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Wang CR, McFarlane LO, Pukala TL. Exploring snake venoms beyond the primary sequence: From proteoforms to protein-protein interactions. Toxicon 2024; 247:107841. [PMID: 38950738 DOI: 10.1016/j.toxicon.2024.107841] [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: 04/22/2024] [Revised: 06/26/2024] [Accepted: 06/28/2024] [Indexed: 07/03/2024]
Abstract
Snakebite envenomation has been a long-standing global issue that is difficult to treat, largely owing to the flawed nature of current immunoglobulin-based antivenom therapy and the complexity of snake venoms as sophisticated mixtures of bioactive proteins and peptides. Comprehensive characterisation of venom compositions is essential to better understanding snake venom toxicity and inform effective and rationally designed antivenoms. Additionally, a greater understanding of snake venom composition will likely unearth novel biologically active proteins and peptides that have promising therapeutic or biotechnological applications. While a bottom-up proteomic workflow has been the main approach for cataloguing snake venom compositions at the toxin family level, it is unable to capture snake venom heterogeneity in the form of protein isoforms and higher-order protein interactions that are important in driving venom toxicity but remain underexplored. This review aims to highlight the importance of understanding snake venom heterogeneity beyond the primary sequence, in the form of post-translational modifications that give rise to different proteoforms and the myriad of higher-order protein complexes in snake venoms. We focus on current top-down proteomic workflows to identify snake venom proteoforms and further discuss alternative or novel separation, instrumentation, and data processing strategies that may improve proteoform identification. The current higher-order structural characterisation techniques implemented for snake venom proteins are also discussed; we emphasise the need for complementary and higher resolution structural bioanalytical techniques such as mass spectrometry-based approaches, X-ray crystallography and cryogenic electron microscopy, to elucidate poorly characterised tertiary and quaternary protein structures. We envisage that the expansion of the snake venom characterisation "toolbox" with top-down proteomics and high-resolution protein structure determination techniques will be pivotal in advancing structural understanding of snake venoms towards the development of improved therapeutic and biotechnology applications.
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Affiliation(s)
- C Ruth Wang
- Discipline of Chemistry, School of Physics, Chemistry and Earth Sciences, The University of Adelaide, Adelaide, 5005, Australia
| | - Lewis O McFarlane
- Discipline of Chemistry, School of Physics, Chemistry and Earth Sciences, The University of Adelaide, Adelaide, 5005, Australia
| | - Tara L Pukala
- Discipline of Chemistry, School of Physics, Chemistry and Earth Sciences, The University of Adelaide, Adelaide, 5005, Australia.
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Salvador GHM, Cardoso FF, Lomonte B, Fontes MRM. Inhibitors and activators for myotoxic phospholipase A 2-like toxins from snake venoms - A structural overview. Biochimie 2024:S0300-9084(24)00175-5. [PMID: 39089640 DOI: 10.1016/j.biochi.2024.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 06/27/2024] [Accepted: 07/29/2024] [Indexed: 08/04/2024]
Abstract
Snakebite envenomations result in acute and chronic physical and psychological health effects on their victims, leading to a substantial socio-economic burden in tropical and subtropical countries. Local necrosis is one of the serious effects caused by envenomation, primarily induced by snake venoms from the Viperidae family through the direct action of components collectively denominated as myotoxins, including the phopholipase A2-like (PLA2-like) toxins. Considering the limitations of antivenoms in preventing the rapid development of local tissue damage caused by envenomation, the use of small molecule therapeutics has been suggested as potential first-aid treatments or as adjuvants to antivenom therapy. In this review, we provide an overview of the structural interactions of molecules exhibiting inhibitory activity toward PLA2-like toxins. Additionally, we discuss the implications for the myotoxic mechanism of PLA2-like toxins and the molecules involved in their activation, highlighting key differences between activators and inhibitors. Finally, we integrate all these results to propose a classification of inhibitors into three different classes and five sub-classes. Taking into account the structural and affinity information, we compare the different inhibitors/ligands to gain a deeper understanding of the structural basis for the effective inhibition of PLA2-like toxins. By offering these insights, we aim to contribute to the search for new and efficient inhibitor molecules to complement and improve current therapy by conventional antivenoms.
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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
| | - Fábio F Cardoso
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu-SP, Brazil
| | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - 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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3
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Castro-Pinheiro C, Junior LCSP, Sanchez EF, da Silva ACR, Dwan CA, Karpiniec SS, Critchley AT, Fuly AL. Effect of Seaweed-Derived Fucoidans from Undaria pinnatifida and Fucus vesiculosus on Coagulant, Proteolytic, and Phospholipase A 2 Activities of Snake Bothrops jararaca, B. jararacussu, and B. neuwiedi Venom. Toxins (Basel) 2024; 16:188. [PMID: 38668613 PMCID: PMC11053494 DOI: 10.3390/toxins16040188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/04/2024] [Accepted: 04/09/2024] [Indexed: 04/29/2024] Open
Abstract
BACKGROUND Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial. METHODS This study analyzed the potential of two fucoidan sulfated polysaccharides extracted from brown seaweeds Fucus vesiculosus (FVF) and Undaria pinnatifida (UPF) against the fibrinogen or plasma coagulation, proteolytic, and phospholipase A2 (PLA2) activities of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom. The toxicity of FVF and UPF was assessed by the hemocompatibility test. RESULTS FVF and UPF did not lyse human red blood cells. FVF and UPF inhibited the proteolytic activity of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom by approximately 25%, 50%, and 75%, respectively, while all venoms led to a 20% inhibition of PLA2 activity. UPF and FVF delayed plasma coagulation caused by the venoms of B. jararaca and B. neuwiedi but did not affect the activity of B. jararacussu venom. FVF and UPF blocked the coagulation of fibrinogen induced by all these Bothropic venoms. CONCLUSION FVF and UPF may be of importance as adjuvants for SBE caused by species of Bothrops, which are the most medically relevant snakebite incidents in South America, especially Brazil.
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Affiliation(s)
- Camila Castro-Pinheiro
- Department of Molecular and Cellular Biology, Federal Fluminense University, Niterói 24001-970, Rio de Janeiro, Brazil; (C.C.-P.); (L.C.S.P.J.); (A.C.R.d.S.)
| | - Luiz Carlos Simas Pereira Junior
- Department of Molecular and Cellular Biology, Federal Fluminense University, Niterói 24001-970, Rio de Janeiro, Brazil; (C.C.-P.); (L.C.S.P.J.); (A.C.R.d.S.)
| | - Eladio Flores Sanchez
- Laboratory of Biochemistry of Proteins from Animal Venoms, Research and Development Center, Ezequiel Dias Foundation, Belo Horizonte 30510-010, Minas Gerais, Brazil;
| | - Ana Cláudia Rodrigues da Silva
- Department of Molecular and Cellular Biology, Federal Fluminense University, Niterói 24001-970, Rio de Janeiro, Brazil; (C.C.-P.); (L.C.S.P.J.); (A.C.R.d.S.)
| | - Corinna A. Dwan
- Marinova Pty, Ltd., Cambridge, TAS 7170, Australia; (C.A.D.); (S.S.K.)
| | | | - Alan Trevor Critchley
- Independent Researcher, The Evangeline Trail, Highway 1, Paradise, NS B0S 1R0, Canada;
| | - Andre Lopes Fuly
- Department of Molecular and Cellular Biology, Federal Fluminense University, Niterói 24001-970, Rio de Janeiro, Brazil; (C.C.-P.); (L.C.S.P.J.); (A.C.R.d.S.)
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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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Castro-Amorim J, Novo de Oliveira A, Da Silva SL, Soares AM, Mukherjee AK, Ramos MJ, Fernandes PA. Catalytically Active Snake Venom PLA 2 Enzymes: An Overview of Its Elusive Mechanisms of Reaction. J Med Chem 2023; 66:5364-5376. [PMID: 37018514 PMCID: PMC10150362 DOI: 10.1021/acs.jmedchem.3c00097] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Snake venom-secreted phospholipase A2 (svPLA2) enzymes, both catalytically active and inactive, are a central component in envenoming. These are responsible for disrupting the cell membrane's integrity, inducing a wide range of pharmacological effects, such as the necrosis of the bitten limb, cardiorespiratory arrest, edema, and anticoagulation. Although extensively characterized, the reaction mechanisms of enzymatic svPLA2 are still to be thoroughly understood. This review presents and analyses the most plausible reaction mechanisms for svPLA2, such as the "single-water mechanism" or the "assisted-water mechanism" initially proposed for the homologous human PLA2. All of the mechanistic possibilities are characterized by a highly conserved Asp/His/water triad and a Ca2+ cofactor. The extraordinary increase in activity induced by binding to a lipid-water interface, known as "interfacial activation," critical for the PLA2s activity, is also discussed. Finally, a potential catalytic mechanism for the postulated noncatalytic PLA2-like proteins is anticipated.
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Affiliation(s)
- Juliana Castro-Amorim
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Ana Novo de Oliveira
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Saulo Luís Da Silva
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Andreimar M Soares
- Laboratory of Biotechnology of Proteins and Bioactive Compounds (LABIOPROT), Oswaldo Cruz Foundation, National Institute of Epidemiology in the Western Amazon (INCT-EpiAmO), Porto Velho, Rondônia 76812-245, Brazil
- Sao Lucas Universitary Center (UniSL), Porto Velho, Rondônia 76805-846, Brazil
| | - Ashis K Mukherjee
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, Assam, India
- Division of Life Sciences, Institute of Advanced Studies in Science and Technology, Vigyan Path, Garchuk, Paschim Boragaon, Guwahati 781035, Assam, India
| | - Maria João Ramos
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Pedro A Fernandes
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
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Structural and functional studies of a snake venom phospholipase A 2-like protein complexed to an inhibitor from Tabernaemontana catharinensis. Biochimie 2023; 206:105-115. [PMID: 36273763 DOI: 10.1016/j.biochi.2022.10.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/19/2022] [Accepted: 10/17/2022] [Indexed: 11/22/2022]
Abstract
Snake envenomation is an ongoing global health problem and tropical neglected disease that afflicts millions of people each year. The only specific treatment, antivenom, has several limitations that affects its proper distribution to the victims and its efficacy against local effects, such as myonecrosis. The main responsible for this consequence are the phospholipases A2 (PLA2) and PLA2-like proteins, such as BthTX-I from Bothrops jararacussu. Folk medicine resorts to plants such as Tabernaemontana catharinensis to palliate these and other snakebite effects. Here, we evaluated the effect of its root bark extract and one of its isolated compounds, 12-methoxy-4-methyl-voachalotine (MMV), against the in vitro paralysis and muscle damage induced by BthTX-I. Secondary and quaternary structures of BthTX-I were not modified by the interaction with MMV. Instead, this compound interacted in an unprecedented way with the region inside the toxin hydrophobic channel and promoted a structural change in Val31, loop 58-71 and Membrane Disruption Site. Thus, we hypothesize that MMV inhibits PLA2-like proteins by preventing entrance of fatty acid into the hydrophobic channel. These data may explain the traditional use of T. catharinensis extract and confirm MMV as a promising candidate to complement antivenom or a structural guide to develop more effective inhibitors.
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Lomonte B. Lys49 myotoxins, secreted phospholipase A 2-like proteins of viperid venoms: A comprehensive review. Toxicon 2023; 224:107024. [PMID: 36632869 DOI: 10.1016/j.toxicon.2023.107024] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/06/2023] [Accepted: 01/06/2023] [Indexed: 01/11/2023]
Abstract
Muscle necrosis is a potential clinical complication of snakebite envenomings, which in severe cases can lead to functional or physical sequelae such as disability or amputation. Snake venom proteins with the ability to directly damage skeletal muscle fibers are collectively referred to as myotoxins, and include three main types: cytolysins of the "three-finger toxin" protein family expressed in many elapid venoms, the so-called "small" myotoxins found in a number of rattlesnake venoms, and the widespread secreted phospholipase A2 (sPLA2) molecules. Among the latter, protein variants that conserve the sPLA2 structure, but lack such enzymatic activity, have been increasingly found in the venoms of many viperid species. Intriguingly, these sPLA2-like proteins are able to induce muscle necrosis by a mechanism independent of phospholipid hydrolysis. They are commonly referred to as "Lys49 myotoxins" since they most often present, among other substitutions, the replacement of the otherwise invariant residue Asp49 of sPLA2s by Lys. This work comprehensively reviews the historical developments and current knowledge towards deciphering the mechanism of action of Lys49 sPLA2-like myotoxins, and points out main gaps to be filled for a better understanding of these multifaceted snake venom proteins, to hopefully lead to improved treatments for snakebites.
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Affiliation(s)
- Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, 11501, Costa Rica.
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Solving the microheterogeneity of Bothrops asper myotoxin-II by high-resolution mass spectrometry: Insights into C-terminal region variability in Lys49-phospholipase A2 homologs. Toxicon 2022; 210:123-131. [DOI: 10.1016/j.toxicon.2022.02.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 02/27/2022] [Accepted: 02/28/2022] [Indexed: 11/21/2022]
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Borges RJ, Salvador GHM, Pimenta DC, Dos Santos LD, Fontes MRM, Usón I. SEQUENCE SLIDER: integration of structural and genetic data to characterize isoforms from natural sources. Nucleic Acids Res 2022; 50:e50. [PMID: 35104880 PMCID: PMC9122596 DOI: 10.1093/nar/gkac029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 01/05/2022] [Accepted: 01/30/2022] [Indexed: 12/28/2022] Open
Abstract
Proteins isolated from natural sources can be composed of a mixture of isoforms with similar physicochemical properties that coexist in the final steps of purification. Yet, even where unverified, the assumed sequence is enforced throughout the structural studies. Herein, we propose a novel perspective to address the usually neglected sequence heterogeneity of natural products by integrating biophysical, genetic and structural data in our program SEQUENCE SLIDER. The aim is to assess the evidence supporting chemical composition in structure determination. Locally, we interrogate the experimental map to establish which side chains are supported by the structural data, and the genetic information relating sequence conservation is integrated into this statistic. Hence, we build a constrained peptide database, containing most probable sequences to interpret mass spectrometry data (MS). In parallel, we perform MS de novo sequencing with genomic-based algorithms to detect point mutations. We calibrated SLIDER with Gallus gallus lysozyme, whose sequence is unequivocally established and numerous natural isoforms are reported. We used SLIDER to characterize a metalloproteinase and a phospholipase A2-like protein from the venom of Bothrops moojeni and a crotoxin from Crotalus durissus collilineatus. This integrated approach offers a more realistic structural descriptor to characterize macromolecules isolated from natural sources.
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Affiliation(s)
- Rafael J Borges
- Departament of Biophysics and Pharmacology, Biosciences Institute, São Paulo State University (UNESP), Botucatu, São Paulo 18618-689, Brazil.,Crystallographic Methods, Institute of Molecular Biology of Barcelona (IBMB-CSIC), Barcelona 08028, Spain
| | - Guilherme H M Salvador
- Departament of Biophysics and Pharmacology, Biosciences Institute, São Paulo State University (UNESP), Botucatu, São Paulo 18618-689, Brazil
| | - Daniel C Pimenta
- Biochemistry and Biophysics Laboratory, Butantan Institute, São Paulo, São Paulo 05503-900, Brazil
| | - Lucilene D Dos Santos
- Graduate Program in Tropical Diseases, Botucatu Medical School (FMB), São Paulo State University (UNESP), Botucatu, São Paulo 18618-687, Brazil.,Biotechnology Institute (IBTEC), São Paulo State University (UNESP), Botucatu, São Paulo 18607-440, Brazil
| | - Marcos R M Fontes
- Departament of Biophysics and Pharmacology, Biosciences Institute, São Paulo State University (UNESP), Botucatu, São Paulo 18618-689, Brazil
| | - Isabel Usón
- Crystallographic Methods, Institute of Molecular Biology of Barcelona (IBMB-CSIC), Barcelona 08028, Spain.,ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
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