1
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Montero-Dominguez PA, Corzo G. Characterization of the coupling mechanism of scorpion β-neurotoxins on the voltage-gated sodium channel hNav1.6. J Biomol Struct Dyn 2023; 41:14419-14427. [PMID: 36812246 DOI: 10.1080/07391102.2023.2181629] [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: 11/17/2022] [Accepted: 02/12/2023] [Indexed: 02/24/2023]
Abstract
Scorpion β-neurotoxins represent a pharmacological group that affects voltage-gated sodium channels (Nav). Despite knowing the electrophysiological effect of these toxins on Nav channels, the molecular mechanism by which the union is carried out is still undetermined. In this study, computational techniques such as modeling, docking and molecular dynamics were used to elucidate the mechanism of interaction between scorpion β-neurotoxins using the neurotoxin nCssII and its recombinant variant CssII-RCR, which bind to the site-4, an extracellular receptor, of the human sodium channel hNav1.6. Different modes of interaction were observed for both toxins, where the main distinguishing feature was the interaction generated by the residue E15 on such site-4; that is, E15 in nCssII exhibits an interaction with the voltage-sensing domain II, and the same residue E15 of CssII-RCR exhibits an interaction with domain III. Despite this difference in interaction by E15, it is seen that both neurotoxins interact with similar regions of the voltage sensing domain such as the S3-S4 connecting loop (L834-E838) of the hNav1.6. Our simulations present a first approach to the mode of interaction of scorpion beta-neurotoxins in toxin-receptor complexes, being able to explain at the molecular level the phenomenon of voltage sensor entrapment generated by these toxins.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Pavel Andrei Montero-Dominguez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Mor, México
| | - Gerardo Corzo
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Mor, México
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2
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Heterologous expression of four recombinant toxins from Panamanian scorpions of the genus Tityus and Centruroides for production of antivenom. Toxicon X 2022; 13:100090. [PMID: 35024608 PMCID: PMC8728522 DOI: 10.1016/j.toxcx.2021.100090] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/13/2021] [Accepted: 12/15/2021] [Indexed: 11/24/2022] Open
Abstract
Background The development of more effective antivenoms remains a necessity for countries where scorpionism is a public health problem. Also, the regionalization of antivenoms may be important for some countries with special scorpionism characteristics. Objective Production of antibodies capable of neutralizing the lethal effect of the venom of three scorpion species from Panama. Methods The primary structures of two neurotoxins from T. pachyurus, one from T. cerroazul and another from C. bicolor were elucidated using N-terminal amino acid degradation and Sanger gene cloned sequencing. The obtained mRNA transcripts were cloned and expressed using E. coli vectors. Different bacterial expression conditions were tested and the best culture conditions for each expressed protein is reported. The expressed scorpion toxins were purified by chromatographic methods and used as immunogens in rabbits. Results The antibodies produced under the reported immunization scheme show better neutralization (ED50) than other reported commercial antivenoms used to neutralize similar species scorpion venoms under similar LD50 conditions. Conclusion The information reported here shows the proof of concept for selecting recombinant immunogens with the ability to produce antibodies for neutralizing the lethal effects of the most important medical species of scorpions in Panama. The structure of four new neurotoxins from three panamanian scorpions were elucidated. The four neurotoxins were recombinantly expressed and were immunogenic to rabbits. Rabitt sera raised against them were able to recognize scorpion neurotoxins from panamanian scorpions.
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3
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Riaño-Umbarila L, Romero-Moreno JA, Ledezma-Candanoza LM, Olamendi-Portugal T, Possani LD, Becerril B. Full Neutralization of Centruroidessculpturatus Scorpion Venom by Combining Two Human Antibody Fragments. Toxins (Basel) 2021; 13:toxins13100708. [PMID: 34679001 PMCID: PMC8540208 DOI: 10.3390/toxins13100708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/01/2021] [Accepted: 10/03/2021] [Indexed: 11/16/2022] Open
Abstract
A fundamental issue of the characterization of single-chain variable fragments (scFvs), capable of neutralizing scorpion toxins, is their cross-neutralizing ability. This aspect is very important in Mexico because all scorpions dangerous to humans belong to the Centruroides genus, where toxin sequences show high identity. Among toxin-neutralizing antibodies that were generated in a previous study, scFv 10FG2 showed a broad cross-reactivity against several Centruroides toxins, while the one of scFv LR is more limited. Both neutralizing scFvs recognize independent epitopes of the toxins. In the present work, the neutralization capacity of these two scFvs against two medically important toxins of the venom of Centruroides sculpturatus Ewing was evaluated. The results showed that these toxins are recognized by both scFvs with affinities between 1.8 × 10-9 and 6.1 × 10-11 M. For this reason, their ability to neutralize the venom was evaluated in mice, where scFv 10FG2 showed a better protective capacity. A combination of both scFvs at a molar ratio of 1:5:5 (toxins: scFv 10FG2: scFv LR) neutralized the venom without the appearance of any signs of intoxication. These results indicate a complementary activity of these two scFvs during venom neutralization.
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Affiliation(s)
- Lidia Riaño-Umbarila
- CONACYT, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca 62250, Morelos, Mexico;
| | - José Alberto Romero-Moreno
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca 62250, Morelos, Mexico; (J.A.R.-M.); (L.M.L.-C.); (T.O.-P.); (L.D.P.)
| | - Luis M. Ledezma-Candanoza
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca 62250, Morelos, Mexico; (J.A.R.-M.); (L.M.L.-C.); (T.O.-P.); (L.D.P.)
| | - Timoteo Olamendi-Portugal
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca 62250, Morelos, Mexico; (J.A.R.-M.); (L.M.L.-C.); (T.O.-P.); (L.D.P.)
| | - Lourival D. Possani
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca 62250, Morelos, Mexico; (J.A.R.-M.); (L.M.L.-C.); (T.O.-P.); (L.D.P.)
| | - Baltazar Becerril
- Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca 62250, Morelos, Mexico
- Correspondence:
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4
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Zhu S, Gao B, Peigneur S, Tytgat J. How a Scorpion Toxin Selectively Captures a Prey Sodium Channel: The Molecular and Evolutionary Basis Uncovered. Mol Biol Evol 2021; 37:3149-3164. [PMID: 32556211 DOI: 10.1093/molbev/msaa152] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The growing resistance of insects to chemical pesticides is reducing the effectiveness of conventional methods for pest control and thus, the development of novel insecticidal agents is imperative. Scorpion toxins specific for insect voltage-gated sodium channels (Navs) have been considered as one of the most promising insecticide alternatives due to their host specificity, rapidly evoked toxicity, biodegradability, and the lack of resistance. However, they have not been developed for uses in agriculture and public health, mainly because of a limited understanding of their molecular and evolutionary basis controlling their phylogenetic selectivity. Here, we show that the traditionally defined insect-selective scorpion toxin LqhIT2 specifically captures a prey Nav through a conserved trapping apparatus comprising a three-residue-formed cavity and a structurally adjacent leucine. The former serves as a detector to recognize and bind a highly exposed channel residue conserved in insects and spiders, two major prey items for scorpions; and the latter subsequently seizes the "moving" voltage sensor via hydrophobic interactions to reduce activation energy for channel opening, demonstrating its action in an enzyme-like manner. Based on the established toxin-channel interaction model in combination with toxicity assay, we enlarged the toxic spectrum of LqhIT2 to spiders and certain other arthropods. Furthermore, we found that genetic background-dependent cavity shapes determine the species selectivity of LqhIT2-related toxins. We expect that the discovery of the trapping apparatus will improve our understanding of the evolution and design principle of Nav-targeted toxins from a diversity of arthropod predators and accelerate their uses in pest control.
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Affiliation(s)
- Shunyi Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects & Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Bin Gao
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects & Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Steve Peigneur
- Department of Toxicology and Pharmacology, University of Leuven (KU Leuven), Leuven, Belgium
| | - Jan Tytgat
- Department of Toxicology and Pharmacology, University of Leuven (KU Leuven), Leuven, Belgium
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5
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Saikia C, Ben-Nissan G, Reuveny E, Karbat I. Production of recombinant venom peptides as tools for ion channel research. Methods Enzymol 2021; 654:169-201. [PMID: 34120712 DOI: 10.1016/bs.mie.2021.01.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Animal venom is a rich source for peptide toxins that bind and modulate the function of ion channels. Owing to their ability to bind receptor sites on the channel protein with high affinity and specificity, peptide neurotoxins have become an indispensable tool for ion channel research. Recent breakthroughs in structural biology and advances in computer simulations of biomolecules have sparked a new interest in animal toxins as probes of channel protein structure and function. Here, we focus on methods used to produce animal toxins for research purposes using recombinant expression. The specific challenges associated with heterologous production of venom peptides are discussed, and several methods targeting these issues are presented with an emphasis on E. coli based systems. An efficient protocol for the bacterial expression, folding, and purification of recombinant venom peptides is described.
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Affiliation(s)
- Chandamita Saikia
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Gili Ben-Nissan
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Eitan Reuveny
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
| | - Izhar Karbat
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
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6
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Alvarado D, Cardoso-Arenas S, Corrales-García LL, Clement H, Arenas I, Montero-Dominguez PA, Olamendi-Portugal T, Zamudio F, Csoti A, Borrego J, Panyi G, Papp F, Corzo G. A Novel Insecticidal Spider Peptide that Affects the Mammalian Voltage-Gated Ion Channel hKv1.5. Front Pharmacol 2021; 11:563858. [PMID: 33597864 PMCID: PMC7883638 DOI: 10.3389/fphar.2020.563858] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 10/26/2020] [Indexed: 11/20/2022] Open
Abstract
Spider venoms include various peptide toxins that modify the ion currents, mainly of excitable insect cells. Consequently, scientific research on spider venoms has revealed a broad range of peptide toxins with different pharmacological properties, even for mammal species. In this work, thirty animal venoms were screened against hKv1.5, a potential target for atrial fibrillation therapy. The whole venom of the spider Oculicosa supermirabilis, which is also insecticidal to house crickets, caused voltage-gated potassium ion channel modulation in hKv1.5. Therefore, a peptide from the spider O. supermirabilis venom, named Osu1, was identified through HPLC reverse-phase fractionation. Osu1 displayed similar biological properties as the whole venom; so, the primary sequence of Osu1 was elucidated by both of N-terminal degradation and endoproteolytic cleavage. Based on its primary structure, a gene that codifies for Osu1 was constructed de novo from protein to DNA by reverse translation. A recombinant Osu1 was expressed using a pQE30 vector inside the E. coli SHuffle expression system. recombinant Osu1 had voltage-gated potassium ion channel modulation of human hKv1.5, and it was also as insecticidal as the native toxin. Due to its novel primary structure, and hypothesized disulfide pairing motif, Osu1 may represent a new family of spider toxins.
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Affiliation(s)
- Diana Alvarado
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Samuel Cardoso-Arenas
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Ligia-Luz Corrales-García
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
- Departamento de Alimentos, Facultad de Ciencias Farmacéuticas y Alimentarias, Universidad de Antioquia, Medellín, Colombia
| | - Herlinda Clement
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Iván Arenas
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Pavel Andrei Montero-Dominguez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Timoteo Olamendi-Portugal
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Fernando Zamudio
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Agota Csoti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Jesús Borrego
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Ferenc Papp
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Gerardo Corzo
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
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7
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New Insectotoxin from Tibellus Oblongus Spider Venom Presents Novel Adaptation of ICK Fold. Toxins (Basel) 2021; 13:toxins13010029. [PMID: 33406803 PMCID: PMC7824768 DOI: 10.3390/toxins13010029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/21/2020] [Accepted: 12/30/2020] [Indexed: 11/17/2022] Open
Abstract
The Tibellus oblongus spider is an active predator that does not spin webs and remains poorly investigated in terms of venom composition. Here, we present a new toxin, named Tbo-IT2, predicted by cDNA analysis of venom glands transcriptome. The presence of Tbo-IT2 in the venom was confirmed by proteomic analyses using the LC-MS and MS/MS techniques. The distinctive features of Tbo-IT2 are the low similarity of primary structure with known animal toxins and the unusual motif of 10 cysteine residues distribution. Recombinant Tbo-IT2 (rTbo-IT2), produced in E. coli using the thioredoxin fusion protein strategy, was structurally and functionally studied. rTbo-IT2 showed insecticidal activity on larvae of the housefly Musca domestica (LD100 200 μg/g) and no activity on the panel of expressed neuronal receptors and ion channels. The spatial structure of the peptide was determined in a water solution by NMR spectroscopy. The Tbo-IT2 structure is a new example of evolutionary adaptation of a well-known inhibitor cystine knot (ICK) fold to 5 disulfide bonds configuration, which determines additional conformational stability and gives opportunities for insectotoxicity and probably some other interesting features.
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8
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C-Terminal Amidation of Chlorotoxin Does Not Affect Tumour Cell Proliferation and Has No Effect on Toxin Cytotoxicity. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-020-10117-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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9
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López-Giraldo AE, Olamendi-Portugal T, Riaño-Umbarila L, Becerril B, Possani LD, Delepierre M, del Río-Portilla F. The three-dimensional structure of the toxic peptide Cl13 from the scorpion Centruroides limpidus. Toxicon 2020; 184:158-166. [DOI: 10.1016/j.toxicon.2020.06.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 12/27/2022]
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10
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Anti-tumoral effect of scorpion peptides: Emerging new cellular targets and signaling pathways. Cell Calcium 2019; 80:160-174. [DOI: 10.1016/j.ceca.2019.05.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/10/2019] [Accepted: 05/10/2019] [Indexed: 12/31/2022]
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11
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Riaño-Umbarila L, Gómez-Ramírez IV, Ledezma-Candanoza LM, Olamendi-Portugal T, Rodríguez-Rodríguez ER, Fernández-Taboada G, Possani LD, Becerril B. Generation of a Broadly Cross-Neutralizing Antibody Fragment against Several Mexican Scorpion Venoms. Toxins (Basel) 2019; 11:toxins11010032. [PMID: 30634620 PMCID: PMC6356842 DOI: 10.3390/toxins11010032] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/03/2019] [Accepted: 01/03/2019] [Indexed: 12/19/2022] Open
Abstract
The recombinant antibody fragments generated against the toxic components of scorpion venoms are considered a promising alternative for obtaining new antivenoms for therapy. Using directed evolution and site-directed mutagenesis, it was possible to generate a human single-chain antibody fragment with a broad cross-reactivity that retained recognition for its original antigen. This variant is the first antibody fragment that neutralizes the effect of an estimated 13 neurotoxins present in the venom of nine species of Mexican scorpions. This single antibody fragment showed the properties of a polyvalent antivenom. These results represent a significant advance in the development of new antivenoms against scorpion stings, since the number of components would be minimized due to their broad cross-neutralization capacity, while at the same time bypassing animal immunization.
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Affiliation(s)
- Lidia Riaño-Umbarila
- CONACYT, Instituto de Biotecnología-Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Ilse V Gómez-Ramírez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Luis M Ledezma-Candanoza
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Timoteo Olamendi-Portugal
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Everardo Remi Rodríguez-Rodríguez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Guillermo Fernández-Taboada
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Lourival D Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
| | - Baltazar Becerril
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 62250, Mexico.
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12
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Leyva E, Medrano-Cerano JL, Cano-Sánchez P, López-González I, Gómez-Velasco H, del Río-Portilla F, García-Hernández E. Bacterial expression, purification and biophysical characterization of wheat germ agglutinin and its four hevein-like domains. Biopolymers 2018; 110:e23242. [DOI: 10.1002/bip.23242] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/25/2018] [Accepted: 11/07/2018] [Indexed: 12/27/2022]
Affiliation(s)
- Eduardo Leyva
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
| | - Jorge L. Medrano-Cerano
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
| | - Patricia Cano-Sánchez
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
| | - Itzel López-González
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
| | - Homero Gómez-Velasco
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
| | - Federico del Río-Portilla
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
| | - Enrique García-Hernández
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria; México Mexico
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13
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Yang F, Liu S, Zhang Y, Qin C, Xu L, Li W, Cao Z, Li W, Wu Y. Expression of recombinant α-toxin BmKM9 from scorpion Buthus martensii Karsch and its functional characterization on sodium channels. Peptides 2018; 99:153-160. [PMID: 28986244 DOI: 10.1016/j.peptides.2017.09.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/15/2017] [Accepted: 09/27/2017] [Indexed: 12/19/2022]
Abstract
Scorpion toxins are invaluable pharmacological tools for studying ion channels and potential drugs for channelopathies. The long-chain toxins from scorpion venom with four disulfide bridges exhibit their unusual bioactivity or biotoxicity by acting on the sodium channels. However, the functional properties of most toxins are still unclear due to their tiny amounts in crude venom and their challenging production by chemical and gene engineering techniques. Here, we expressed one of the long-chain α-toxins, BmKM9, found in the venom of the scorpion Buthus martensii Karsch and characterized its pharmacological properties on sodium channels. Unlike previous toxin production, the recombinant BmKM9 (rBmKM9) possessed no additional amino acid residues such as the His-tag and thrombin cleavage site. The refolded toxin could inhibit the inactivation of rNav1.4, hNav1.5 and hNav1.7 sodium channels. Dose-response experiments were further conducted on these channels. The calculated EC50 values were 131.7±6.6nM for rNav1.4, 454.2±50.1nM for hNav1.5 and 30.9±10.3μM for hNav1.7. The channel activation experiments indicated that the rBmKM9 toxin could shift the activation curves of rNav1.4 and hNav1.5 channels toward a more negative direction and present the typical features of a β-toxin. However, instead of the same activation property on sodium channels, the rBmKM9 toxin could result in different inactivation shift capabilities on rNav1.4 and hNav1.5 channels. The V1/2 values of the steady-state inactivation were altered to be more positive for rNav1.4 and more negative for hNav1.5. Moreover, the recovery of the hNav1.5 channel from inactivation was more significantly delayed than that of the rNav1.4 channel by exposure to rBmKM9. Together, these findings highlighted that the rBmKM9 toxin presents the pharmacological properties of both α- and β-toxins, which would increase the challenge to the classical classification of scorpion toxins. Furthermore, the expression method and functional information on sodium channels would promote the potential application of toxins and contribute to further channel structural and functional studies.
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Affiliation(s)
- Fan Yang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Shuang Liu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Yaoyun Zhang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Chenhu Qin
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Lingna Xu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Wenhua Li
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Biodrug Research Center, Wuhan University, Wuhan 430072, China
| | - Zhijian Cao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Biodrug Research Center, Wuhan University, Wuhan 430072, China
| | - Wenxin Li
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Biodrug Research Center, Wuhan University, Wuhan 430072, China.
| | - Yingliang Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Biodrug Research Center, Wuhan University, Wuhan 430072, China.
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Johnson SR, Rikli HG, Schmidt JO, Evans MS. A reexamination of poneratoxin from the venom of the bullet ant Paraponera clavata. Peptides 2017; 98:51-62. [PMID: 27266841 DOI: 10.1016/j.peptides.2016.05.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Revised: 05/29/2016] [Accepted: 05/31/2016] [Indexed: 12/19/2022]
Abstract
In 1991, Piek et al. [45] described a voltage-gated sodium channel (VGSC) modifier from "bullet ant" (Paraponera clavata) venom they called poneratoxin (PoTx). Using UV chromatography and Edman degradation they showed two "identical peptides" of 25 residues. We reinvestigated PoTx using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-TMS). De novo sequencing showed the two peptides were actually structurally different peptides: the originally described PoTx and a glycyl pro-peptide (glycyl-PoTx) that lacks C-terminus amidation. We examined P. clavata venom from different geographical locations and discovered two additional PoTx analogs: an A23E substitution analog and a D22N; A23V substitutions analog. We tested PoTx and these three natural analogs on the mammalian sensory voltage-gated sodium channel, Nav1.7, using whole cell voltage-clamp. PoTx and each analog induced slowly activating currents in response to small depolarizing steps and sustained currents due to blockade of channel inactivation, similar to that described previously in skeletal muscle [19]. Glycyl-PoTx had the same potency and efficacy as PoTx. A23E PoTx, with a decrease in both C-terminal net positive charge and hydrophobicity, had an eight-fold reduction in potency compared to PoTx. In contrast, the D22N; A23V PoTx, with an increase in both C-terminal net positive charge and hydrophobicity, had a nearly five-fold increase in potency compared to PoTx. We found that changes in PoTx C-terminus caused a significant change in PoTx potency.
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Affiliation(s)
- Stephen R Johnson
- Department of Biology, University of Illinois Springfield, Springfield, IL, United States; Department of Chemistry, University of Illinois Springfield, Springfield, IL, United States; Carbon Dynamics Institute, LLC, Sherman, IL, United States.
| | - Hillary G Rikli
- Department of Biology, University of Illinois Springfield, Springfield, IL, United States; Department of Chemistry, University of Illinois Springfield, Springfield, IL, United States
| | | | - M Steven Evans
- Department of Neurology, University of Louisville, Louisville, KY, United States
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Estrada-Gómez S, Gomez-Rave L, Vargas-Muñoz LJ, van der Meijden A. Characterizing the biological and biochemical profile of six different scorpion venoms from the Buthidae and Scorpionidae family. Toxicon 2017; 130:104-115. [PMID: 28209477 DOI: 10.1016/j.toxicon.2017.02.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/08/2017] [Accepted: 02/11/2017] [Indexed: 11/25/2022]
Abstract
The objective of this study was to characterize six different scorpion venoms using biological and biochemical methods, including a preliminary MS/MS and a post-translational modifications analysis. Despite the diversity of scorpion species of medical importance in Africa and Colombia, the venoms of these arachnids have been poorly studied in these two regions. We report the biochemical, electrophoretic, chromatographic profile, internal peptide sequences with a post-translational modification report, and a preliminary antitumor activity of five different scorpions of the Buthidae family, Androctonus amoreuxi, Babycurus jacksoni, Grosphus grandidieri, Hottentotta gentili and Tityus fuhrmanni, and one of the Scorpionidae family Pandinus imperator. No L-amino oxidase activity was detected in the evaluated venoms. Proteolytic activity using azocasein was detected only in G. grandidieri and P. imperator, indicating the possible presence of metalloproteinases in these two venoms. Proteolytic activity using NOBA was detected in all venoms indicating the possible presence of serine-proteinases. Phospholipase A2 activity was detected in the venoms of P. imperator, G. grandidieri, H. gentili and A. amoreuxi, with P. imperator venom being the most active. All venoms analyzed contained defensin-like proteins, alpha toxins, metalloproteinases, neuropeptides, DBP affecting ion channels, DBP with antimicrobial activity, among others. Venoms from P. imperator, G. grandidieri and T. fuhrmanni showed a dose-dependent cytotoxic activity over MCF-7 cells. Only two isolated RP-HPLC fractions from P. imperator and T. fuhrmanni showed cytotoxic activity over MCF-7. No cytotoxic activity was found in the venoms from A. amoreuxi, B. jacksoni, and H. gentili.
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Affiliation(s)
- Sebastian Estrada-Gómez
- Programa de Ofidismo/Escorpionismo - Serpentario, Universidad de Antioquia UdeA, Carrera 53 No 61-30, Medellín, 050010, Antioquia, Colombia; Facultad de Ciencias Farmacéuticas y Alimentarias, Universidad de Antioquia UdeA, Calle 70 No 52-21, Medellín, 050010, Antioquia, Colombia.
| | - Lyz Gomez-Rave
- Programa de Ofidismo/Escorpionismo - Serpentario, Universidad de Antioquia UdeA, Carrera 53 No 61-30, Medellín, 050010, Antioquia, Colombia; Maestría Bioquímica Clínica, Facultad de Ciencias de la Salud, Colegio Mayor de Antioquia, Medellín, 050040, Antioquia, Colombia.
| | - Leidy Johana Vargas-Muñoz
- Facultad de Medicina, Universidad Cooperativa de Colombia, Calle 50 A No 41-20, Medellín, 050012, Antioquia, Colombia.
| | - Arie van der Meijden
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Campus Agrário de Vairão, P-4485-661 Vila do Conde, Portugal.
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Vargas-Jaimes L, Xiao L, Zhang J, Possani LD, Valdivia HH, Quintero-Hernández V. Recombinant expression of Intrepicalcin from the scorpion Vaejovis intrepidus and its effect on skeletal ryanodine receptors. Biochim Biophys Acta Gen Subj 2017; 1861:936-946. [PMID: 28159581 DOI: 10.1016/j.bbagen.2017.01.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 01/22/2017] [Accepted: 01/30/2017] [Indexed: 01/02/2023]
Abstract
BACKGROUND Scorpion venoms contain toxins that modulate ionic channels, among which are the calcins, a small group of short, basic peptides with an Inhibitor Cystine Knot (ICK) motif that target calcium release channels/ryanodine receptors (RyRs) with high affinity and selectivity. Here we describe the heterologous expression of Intrepicalcin, identified by transcriptomic analysis of venomous glands from Vaejovis intrepidus. METHODS Recombinant Intrepicalcin was obtained in Escherichia coli BL21-DE3 (periplasm) by fusing the Intrepicalcin gene to sequences coding for signal-peptide, thioredoxin, His-tag and enterokinase cleavage site. RESULTS [3H]Ryanodine binding, used as a functional index of RyR activity, revealed that recombinant Intrepicalcin activates skeletal RyR (RyR1) dose-dependently with Kd=17.4±4.0nM. Intrepicalcin significantly augments the bell-shaped [Ca2+]-[3H]ryanodine binding curve at all [Ca2+] ranges, as is characteristic of the calcins. In single channel recordings, Intrepicalcin induces the appearance of a subconductance state in RyR1 with a fractional value ∼55% of the full conductance state, very close to that of Vejocalcin. Furthermore, Intrepicalcin stimulates Ca2+ release at an initial dose=45.3±2.5nM, and depletes ~50% of Ca2+ load from skeletal sarcoplasmic reticulum vesicles. CONCLUSIONS We conclude that active recombinant Intrepicalcin was successfully obtained without the need of manual oxidation, enabling it to target RyR1s with high affinity. GENERAL SIGNIFICANCE This is the first calcin heterologously expressed in the periplasma of Escherichia coli BL21-DE3, shown to be pharmacologically effective, thus paving the way for the generation of Intrepicalcin variants that are required for structure-function relationship studies of calcins and RyRs.
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Affiliation(s)
- Leonel Vargas-Jaimes
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62271, México
| | - Liang Xiao
- Department of Marine Biotechnology, Faculty of Naval Medicine, Second Military Medical University, Shanghai, 200433, China.,Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jing Zhang
- Department of Marine Biotechnology, Faculty of Naval Medicine, Second Military Medical University, Shanghai, 200433, China
| | - Lourival D Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62271, México
| | - Héctor H Valdivia
- Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Verónica Quintero-Hernández
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62271, México.,CONACYT- Laboratorio de Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas-Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, C.P. 72570, Puebla, México
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Corzo G, Espino-Solis GP. Selected scorpion toxin exposures induce cytokine release in human peripheral blood mononuclear cells. Toxicon 2017; 127:56-62. [PMID: 28088477 DOI: 10.1016/j.toxicon.2017.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 12/01/2016] [Accepted: 01/10/2017] [Indexed: 01/09/2023]
Abstract
A cytokine screening on human peripheral blood mononuclear cells (PBMCs) stimulated with selected scorpion toxins (ScTx's) was performed in order to evaluate their effect on human immune cells. The ScTx's chosen for this report were three typical buthid scorpion venom peptides, one with lethal effects on mammals Centruroides suffussus suffusus toxin II (CssII), another, with lethal effects on insects and crustaceans Centruroides noxius toxin 5 (Cn5), and one more without lethal effects Tityus discrepans toxin (Discrepin). A Luminex multiplex analysis was performed in order to determine the amounts chemokines and cytokines IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12-p40, IL-13, interferon alpha (IFN-α), interferon gamma (IFN-γ), tumor necrosis factor alpha TNF-α, and interferon-inducible protein-10 (IP-10) secreted from human PBMCs exposed to these toxins. Although, the ScTx Cn5 is not lethal for mammals, it was able to induce the secretion of cytokines IL-1β, IL-6, and TNF-α, IL-10 and IP-10 in comparison to the lethal CssII, which was able to induce only IP-10 secretion. Discrepin also was able to induce only IP-10. Interestingly, only low amounts of interferons α and β were induced in the presence of the ScTx's assayed. In a synergic experiment, the combination of Discrepin and Cn5 displayed considerable reverse effects on induction of IL-1β, IL-6, IL-10 and TNF-α, but they had a slight synergic effect on IP-10 cytokine production in comparison with the single effect obtained with the Cn5 alone. Thus, the results obtained suggest that the profile of secreted cytokines promoted by ScTx Cn5 is highly related with a cytokine storm event, and also it suggests that the mammalian lethal neurotoxins are not solely responsible of the scorpion envenomation symptomatology.
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Affiliation(s)
- Gerardo Corzo
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, UNAM, Apartado Postal 510-3, Cuernavaca, Morelos 61500, Mexico
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18
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Rodríguez-Rodríguez ER, Olamendi-Portugal T, Serrano-Posada H, Arredondo-López JN, Gómez-Ramírez I, Fernández-Taboada G, Possani LD, Anguiano-Vega GA, Riaño-Umbarila L, Becerril B. Broadening the neutralizing capacity of a family of antibody fragments against different toxins from Mexican scorpions. Toxicon 2016; 119:52-63. [DOI: 10.1016/j.toxicon.2016.05.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/12/2016] [Accepted: 05/18/2016] [Indexed: 10/21/2022]
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19
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Camargos TS, Bosmans F, Rego SC, Mourão CBF, Schwartz EF. The Scorpion Toxin Tf2 from Tityus fasciolatus Promotes Nav1.3 Opening. PLoS One 2015; 10:e0128578. [PMID: 26083731 PMCID: PMC4470819 DOI: 10.1371/journal.pone.0128578] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 04/29/2015] [Indexed: 11/23/2022] Open
Abstract
We identified Tf2, the first β-scorpion toxin from the venom of the Brazilian scorpion Tityus fasciolatus. Tf2 is identical to Tb2-II found in Tityus bahiensis. We found that Tf2 selectively activates human (h)Nav1.3, a neuronal voltage-gated sodium (Nav) subtype implicated in epilepsy and nociception. Tf2 shifts hNav1.3 activation voltage to more negative values, thereby opening the channel at resting membrane potentials. Seven other tested mammalian Nav channels (Nav1.1-1.2; Nav1.4-1.8) expressed in Xenopus oocytes are insensitive upon application of 1 μM Tf2. Therefore, the identification of Tf2 represents a unique addition to the repertoire of animal toxins that can be used to investigate Nav channel function.
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Affiliation(s)
- Thalita S. Camargos
- Departamento de Ciências Fisiológicas, Laboratório de Toxinologia, Universidade de Brasília, Brasília, DF, Brazil
| | - Frank Bosmans
- Department of Physiology, Johns Hopkins University—School of Medicine, Baltimore, MD, United States of America
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University—School of Medicine, Baltimore, MD, United States of America
| | - Solange C. Rego
- Departamento de Ciências Fisiológicas, Laboratório de Toxinologia, Universidade de Brasília, Brasília, DF, Brazil
| | - Caroline B. F. Mourão
- Departamento de Ciências Fisiológicas, Laboratório de Toxinologia, Universidade de Brasília, Brasília, DF, Brazil
| | - Elisabeth F. Schwartz
- Departamento de Ciências Fisiológicas, Laboratório de Toxinologia, Universidade de Brasília, Brasília, DF, Brazil
- * E-mail:
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20
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Estrada-Gómez S, Cupitra NI, Arango WM, Muñoz LJV. Intraspecific variation of centruroides edwardsii venom from two regions of Colombia. Toxins (Basel) 2014; 6:2082-96. [PMID: 25025710 PMCID: PMC4113743 DOI: 10.3390/toxins6072082] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 05/20/2014] [Accepted: 06/06/2014] [Indexed: 01/01/2023] Open
Abstract
We report the first description studies, partial characterization, and intraspecific difference of Centruroides edwardsii, Gervais 1843, venom. C. edwardsii from two Colombian regions (Antioquia and Tolima) were evaluated. Both venoms showed hemolytic activity, possibly dependent of enzymatic active phospholipases, and neither coagulant nor proteolytic activities were observed. Venom electrophoretic profile showed significant differences between C. edwardsii venom from both regions. A high concentration of proteins with molecular masses between 31 kDa and 97.4 kDa, and an important concentration close or below 14.4 kDa were detected. RP-HPLC retention times between 38.2 min and 42.1 min, showed bands close to 14.4 kDa, which may correspond to phospholipases. RP-HPLC venom profile showed a well conserved region in both venoms between 7 and 17 min, after this, significant differences were detected. From Tolima region venom, 50 well-defined peaks were detected, while in the Antioquia region venom, 55 well-defined peaks were detected. Larvicidal activity was only detected in the C. edwardsii venom from Antioquia. No antimicrobial activity was observed using complete venom or RP-HPLC collected fractions of both venoms. Lethally activity (carried out on female albino swiss mice) was detected at doses over 19.2 mg/kg of crude venom. Toxic effects included distress, excitability, eye irritation and secretions, hyperventilation, ataxia, paralysis, and salivation.
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Affiliation(s)
- Sebastián Estrada-Gómez
- Facultad de Quimica Farmaceutica, Universidad de Antioquia UdeA, Carrera 53 No. 61-30, Medellín 050010, Colombia.
| | - Nelson Ivan Cupitra
- Grupo de Investigación de Productos Naturales, Facultad de Ciencias, Universidad del Tolima, Barrio Santa Helena Parte Alta, Ibagué 731020, Colombia.
| | - Walter Murillo Arango
- Grupo de Investigación de Productos Naturales, Facultad de Ciencias, Universidad del Tolima, Barrio Santa Helena Parte Alta, Ibagué 731020, Colombia.
| | - Leidy Johana Vargas Muñoz
- Facultad de Medicina, Universidad Cooperativa de Colombia, Calle 50 A No. 41-20, Medellín 050010, Colombia.
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Coelho V, Cremonez C, Anjolette F, Aguiar J, Varanda W, Arantes E. Functional and structural study comparing the C-terminal amidated β-neurotoxin Ts1 with its isoform Ts1-G isolated from Tityus serrulatus venom. Toxicon 2014; 83:15-21. [DOI: 10.1016/j.toxicon.2014.02.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 02/10/2014] [Accepted: 02/12/2014] [Indexed: 10/25/2022]
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Kövér KE, Batta G. NMR investigation of disulfide containing peptides and proteins. AMINO ACIDS, PEPTIDES AND PROTEINS 2013:37-59. [DOI: 10.1039/9781849737081-00037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
Peptides and proteins with disulfide bonds are abundant in all kingdoms and play essential role in many biological events. Because small disulfide-rich peptides (proteins) are usually difficult to crystallize, nuclear magnetic resonance (NMR) is by far one of the most powerful techniques for the determination of their solution structure. Besides the “static” three-dimensional structure, NMR has unique opportunities to acquire additional information about molecular dynamics and folding at atomic resolution. Nowadays it is becoming increasingly evident, that “excited”, “disordered” or “fuzzy” protein states may exhibit biological function and disulfide proteins are also promising targets for such studies. In this short two-three years overview those disulfide peptides and proteins were cited from the literature that were studied by NMR. Though we may have missed some, their structural diversity and complexity as well as their wide repertoire of biological functions is impressive. We emphasised especially antimicrobial peptides and peptide based toxins in addition to some biologically important other structures. Besides the general NMR methods we reviewed some contemporary techniques suitable for disclosing the peculiar properties of disulfide bonds. Interesting dynamics and folding studies of disulfide proteins were also mentioned. It is important to disclose the essential structure, dynamics, function aspects of disulfide proteins since this aids the design of new compounds with improved activity and reduced toxicity. Undoubtedly, NMR has the potential to accelerate the development of new disulfide peptides/proteins with pharmacological activity.
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