1
|
Lopes KS, Quintanilha MVT, de Souza ACB, Zamudio-Zuñiga F, Possani LD, Mortari MR. Antiseizure potential of peptides from the venom of social wasp Chartergellus communis against chemically-induced seizures. Toxicon 2021; 194:23-36. [PMID: 33610635 DOI: 10.1016/j.toxicon.2021.02.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/26/2021] [Accepted: 02/16/2021] [Indexed: 10/22/2022]
Abstract
Epilepsy is one of the most common neurological diseases in the world. The objective of this research was to investigate a new peptide from the venom of the social wasp Chartergellus communis useful to the study or pharmacotherapy of epilepsy. The wasps were collected, and their venom was extracted. Afterward, the steps of fractionation, sequencing, and identification were carried out to obtain four peptides. These molecules were synthesized for behavioral evaluation tests and electroencephalographic assays to determine their antiseizure potential (induction of acute seizures using the chemical compounds, pentylenetetrazole - PTZ, and pilocarpine - PILO) and analysis of neuropharmacological profile (general spontaneous activity and alteration in motor coordination). Chartergellus-CP1 (i.c.v. - 3.0 μg/animal) caused beneficial alterations in some of the parameters evaluated in both models: PTZ (latency and duration of maximum seizures) and PILO (latency and duration of, and protection against, maximum seizures, and reduction of the median of the seizure scores. When evaluated in 3 doses in the seizure model induced by PILO, the dose of 3.0 μg/animal protected the animals against seizures, with an estimated ED50 of 1.49 μg/animal. Electroencephalographic evaluation of Chartergellus-CP1 showed an improvement in latency, quantity, and percentage of protection against generalized electroencephalographic seizures in the PILO model. Further, Chartergellus-CP1 did not cause adverse effects on general spontaneous activity and motor coordination of animals. This study demonstrated how compounds isolated from wasps' venom may be important resources in the search for new drugs. Such compounds can be considered valuable therapeutic and biotechnological tools for the study and future treatment of epileptic disorders. In this context, a peptide that is potentially useful for epilepsy pharmacotherapy was identified in the venom of C. communis.
Collapse
Affiliation(s)
- Kamila Soares Lopes
- Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, Brasília, Brazil
| | | | | | - Fernando Zamudio-Zuñiga
- Department of Molecular Medicine and Bioprocesses, Institute of Biotechnology, National Autonomous University of Mexico, Morelos, Mexico
| | - Lourival Domingos Possani
- Department of Molecular Medicine and Bioprocesses, Institute of Biotechnology, National Autonomous University of Mexico, Morelos, Mexico
| | - Márcia Renata Mortari
- Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, Brasília, Brazil.
| |
Collapse
|
2
|
Khoshdel Nezamiha F, Imani S, Shahbazzadeh D, Tirgari S, Arabi Mianroodi R. Cloning and expression of OdTx12, a β excitatory toxin from Odontobuthus doriae, in Escherichia coli and evaluation of its bioactivity in Locusta migratoria. Toxicon 2020; 183:20-28. [PMID: 32442468 DOI: 10.1016/j.toxicon.2020.05.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Revised: 04/06/2020] [Accepted: 05/06/2020] [Indexed: 01/11/2023]
Abstract
The venom of Odontobuthus doriae contains several peptide toxins that interfere with the sodium channel function of cell membranes, some of which specifically act on the insect's sodium channel without affecting mammalian cells. In this study sodium channel toxins of Odontobuthus doriae were aligned to other closely related toxins by BLAST and ClustalW servers. Among these toxins, NaTx12 (OdTx12) showed more than 90% similarity to the most known beta excitatory toxin, AaHIT1; furthermore, our modeling studies confirmed high tertiary structure similarity of these proteins. OdTx12 was cloned and expressed in E.coli, using pET26-b and pET28-a expression vectors. Tris-tricine SDS-PAGE and Western blot analysis showed OdTx12 expression by pET28-a, only. After purification, bioactivity of the purified protein was analyzed by injection and oral administration to Locusta migratoria larvae, and toxicity to mammals was tested on mice. Injection of OdTx12 resulted in the killing of larvae with LD50 of 0.4 and 0.2 after 48 and 72 h respectively, but oral administration of OdTx12 had no significant effect on Locusta migratoria, nor did the injection to mice show any signs of toxicity. These results showed that OdTx12, as a novel β excitatory toxin can be considered as a candidate for insect control purposes.
Collapse
Affiliation(s)
| | - Sohrab Imani
- Department of Entomology, Islamic Azad University (Science and Research Branch), Tehran, Iran
| | - Delavar Shahbazzadeh
- Department of Medical Biotechnology of Iran, Venom and Therapeutic Biomolecules Lab, Institute Pasteur of Iran, Tehran, Iran
| | | | - Reza Arabi Mianroodi
- R&D Department, Production and Research Complex, Pasteur Institute of Iran, Tehran, Iran.
| |
Collapse
|
3
|
Cid Uribe JI, Jiménez Vargas JM, Ferreira Batista CV, Zamudio Zuñiga F, Possani LD. Comparative proteomic analysis of female and male venoms from the Mexican scorpion Centruroides limpidus: Novel components found. Toxicon 2017; 125:91-98. [DOI: 10.1016/j.toxicon.2016.11.256] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 11/23/2016] [Indexed: 10/20/2022]
|
4
|
Santibáñez-López CE, Francke OF, Ureta C, Possani LD. Scorpions from Mexico: From Species Diversity to Venom Complexity. Toxins (Basel) 2015; 8:E2. [PMID: 26712787 PMCID: PMC4728524 DOI: 10.3390/toxins8010002] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 11/25/2015] [Accepted: 12/09/2015] [Indexed: 12/13/2022] Open
Abstract
Scorpions are among the oldest terrestrial arthropods, which are distributed worldwide, except for Antarctica and some Pacific islands. Scorpion envenomation represents a public health problem in several parts of the world. Mexico harbors the highest diversity of scorpions in the world, including some of the world's medically important scorpion species. The systematics and diversity of Mexican scorpion fauna has not been revised in the past decade; and due to recent and exhaustive collection efforts as part of different ongoing major revisionary systematic projects, our understanding of this diversity has changed compared with previous assessments. Given the presence of several medically important scorpion species, the study of their venom in the country is also important. In the present contribution, the diversity of scorpion species in Mexico is revised and updated based on several new systematic contributions; 281 different species are recorded. Commentaries on recent venomic, ecological and behavioral studies of Mexican scorpions are also provided. A list containing the most important peptides identified from 16 different species is included. A graphical representation of the different types of components found in these venoms is also revised. A map with hotspots showing the current knowledge on scorpion distribution and areas explored in Mexico is also provided.
Collapse
Affiliation(s)
- Carlos E Santibáñez-López
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca Morelos 62210, Mexico.
| | - Oscar F Francke
- Colección Nacional de Arácnidos, Instituto de Biología, Universidad Nacional Autónoma de México, Circuito exterior s/n, Ciudad Universitaria, Copilco, Coyoacán A.P. 70-233, Distrito Federal 04510, Mexico.
| | - Carolina Ureta
- Laboratorio de Genética Molecular, Desarrollo y Evolución de Plantas, Departamento de Ecología Funcional, Instituto de Ecología, Universidad Autónoma de México, Apartado Postal 70-275, Ciudad Universitaria, Distrito Federal 04510, Mexico.
| | - Lourival D Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca Morelos 62210, Mexico.
| |
Collapse
|
5
|
Monge-Fuentes V, Gomes FMM, Campos GAA, Silva JDC, Biolchi AM, Dos Anjos LC, Gonçalves JC, Lopes KS, Mortari MR. Neuroactive compounds obtained from arthropod venoms as new therapeutic platforms for the treatment of neurological disorders. J Venom Anim Toxins Incl Trop Dis 2015; 21:31. [PMID: 26257776 PMCID: PMC4529710 DOI: 10.1186/s40409-015-0031-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 07/28/2015] [Indexed: 01/25/2023] Open
Abstract
The impact of neurological disorders in society is growing with alarming estimations for an incidence increase in the next decades. These disorders are generally chronic and can affect individuals early during productive life, imposing real limitations on the performance of their social roles. Patients can have their independence, autonomy, freedom, self-image, and self-confidence affected. In spite of their availability, drugs for the treatment of these disorders are commonly associated with side effects, which can vary in frequency and severity. Currently, no effective cure is known. Nowadays, the biopharmaceutical research community widely recognizes arthropod venoms as a rich source of bioactive compounds, providing a plethora of possibilities for the discovery of new neuroactive compounds, opening up novel and attractive opportunities in this field. Several identified molecules with a neuropharmacological profile can act in the central nervous system on different neuronal targets, rendering them useful tools for the study of neurological disorders. In this context, this review aims to describe the current main compounds extracted from arthropod venoms for the treatment of five major existing neurological disorders: stroke, Alzheimer’s disease, epilepsy, Parkinson’s disease, and pathological anxiety.
Collapse
Affiliation(s)
- Victoria Monge-Fuentes
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Flávia Maria Medeiros Gomes
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Gabriel Avohay Alves Campos
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Juliana de Castro Silva
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Andréia Mayer Biolchi
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Lilian Carneiro Dos Anjos
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Jacqueline Coimbra Gonçalves
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Kamila Soares Lopes
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Márcia Renata Mortari
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| |
Collapse
|
6
|
Quintero-Hernández V, Ortiz E, Rendón-Anaya M, Schwartz EF, Becerril B, Corzo G, Possani LD. Scorpion and spider venom peptides: gene cloning and peptide expression. Toxicon 2011; 58:644-63. [PMID: 21978889 DOI: 10.1016/j.toxicon.2011.09.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 09/08/2011] [Accepted: 09/22/2011] [Indexed: 01/05/2023]
Abstract
This communication reviews most of the important findings related to venom components isolated from scorpions and spiders, mainly by means of gene cloning and expression. Rather than revising results obtained by classical biochemical studies that report structure and function of venom components, here the emphasis is placed on cloning and identification of genes present in the venomous glands of these arachnids. Aspects related to cDNA library construction, specific or random ESTs cloning, transcriptome analysis, high-throughput screening, heterologous expression and folding are briefly discussed, showing some numbers of species and components already identified, but also shortly mentioning limitations and perspectives of research for the future in this field.
Collapse
Affiliation(s)
- V Quintero-Hernández
- Instituto de Biotecnología - UNAM, Avenida Universidad, Colonia Chamilpa, Cuernavaca, Morelos, Mexico
| | | | | | | | | | | | | |
Collapse
|
7
|
Dolashka P, Moshtanska V, Borisova V, Dolashki A, Stevanovic S, Dimanov T, Voelter W. Antimicrobial proline-rich peptides from the hemolymph of marine snail Rapana venosa. Peptides 2011; 32:1477-83. [PMID: 21703315 DOI: 10.1016/j.peptides.2011.05.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 05/03/2011] [Accepted: 05/03/2011] [Indexed: 11/16/2022]
Abstract
Hemolymph of Rapana venosa snails is a complex mixture of biochemically and pharmacologically active components such as peptides and proteins. Antimicrobial peptides are gaining attention as antimicrobial alternatives to chemical food preservatives and commonly used antibiotics. Therefore, for the first time we have explored the isolation, identification and characterisation of 11 novel antimicrobial peptides produced by the hemolymph of molluscs. The isolated peptides from the hemolymph applying ultrafiltration and reverse-phase high-performance liquid chromatography (RP-HPLC) have molecular weights between 3000 and 9500 Da, determined by mass spectrometric analysis. The N-terminal sequences of the peptides identified by Edman degradation matched no peptides in the MASCOT search database, indicating novel proline-rich peptides. UV spectra revealed that these substances possessed the characteristics of protein peptides with acidic isoelectric points. However, no Cotton effects were observed between 190 and 280 nm by circular dichroism spectroscopy. Four of the pro-rich peptides also showed strong antimicrobial activities against tested microorganisms including Gram-positive and Gram-negative bacteria.
Collapse
Affiliation(s)
- Pavlina Dolashka
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, G. Bonchev 9, Sofia 1113, Bulgaria.
| | | | | | | | | | | | | |
Collapse
|
8
|
Wang Z, Wang W, Shao Z, Gao B, Li J, Ma J, Li J, Che H, Zhang W. Eukaryotic expression and purification of anti-epilepsy peptide of Buthus martensii Karsch and its protein interactions. Mol Cell Biochem 2009; 330:97-104. [PMID: 19370317 DOI: 10.1007/s11010-009-0104-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2008] [Accepted: 03/30/2009] [Indexed: 11/28/2022]
Abstract
The Asian scorpion Buthus martensil Karsch is important in the Chinese traditional medicine where it is used for the treatment of some nervous system diseases. The anti-epilepsy peptide (AEP) is a 61-amino-acid polypeptide extracted from the venom of B. martensil Karsch. Research has confirmed that it has anti-epileptic effects on the rat model of epilepsy. In this experiment, a cDNA library of AEP from the venom of B. martensil Karsch was constructed using RT-PCR; the primer was designed and used for the amplification. An expression vector of AEP was constructed using Pichia pastoris. Vector expression was induced, and protein purification was then performed. Bolting of the interaction molecule of AEP was by His pull down. Experimental results indicate high AEP expression, and the obtained protein was purified and compared with the control group. Four conspicuous protein bands were observed, and mass chromatographic analysis indicated that the four proteins were synaptosomal-associated protein of 25 kDa (SNAP-25), glial fibrillary acidic protein (GFAP), Glutamic acid decarboxylase (GAD) and N-methyl-D: -aspartate (NMDA). Further, the four protein bands were verified by mammalian two-hybrid experiments and co-immunoprecipitation. AEP was found to interact with SNAP2 and NMDA. This provides experimental evidence for the mechanism of AEP's anti-epileptic action and for the manufacture of a novel type anti-epileptic drug.
Collapse
Affiliation(s)
- Zongren Wang
- Department of Traditional Chinese Medicine, Xijing Hospital, The Forth Military Medical University, Xi'an, Shaanxi, 710032, People's Republic of China.
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Mortari MR, Cunha AOS, Ferreira LB, dos Santos WF. Neurotoxins from invertebrates as anticonvulsants: From basic research to therapeutic application. Pharmacol Ther 2007; 114:171-83. [PMID: 17399793 DOI: 10.1016/j.pharmthera.2007.01.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 01/19/2007] [Accepted: 01/19/2007] [Indexed: 12/21/2022]
Abstract
Invertebrate venoms have attracted considerable interest as a potential source of bioactive substances, especially neurotoxins. These molecules have proved to be extremely useful tools for the understanding of synaptic transmission events, and they have contributed to the design of novel drugs for the treatment of neurological disorders and pain. In this context, as epilepsy involves neuronal substrates, which are sites of action of many neurotoxins; venoms may be particularly useful for antiepileptic drug (AED) research. Epilepsy is a chronic disease whose treatment consists of controlling seizures with antiepileptics that very often induce strong undesirable side effects that may limit treatment. Here, we review the vast, but yet unexplored, world of neurotoxins from invertebrates used as probes in pharmacological screening for novel and less toxic antiepileptics. We briefly review (1) the molecular basis of epilepsy, as well as the sites of action of commonly used anticonvulsants (we bring a comprehensive review of the elements from invertebrate venoms which are mostly studied in neuroscience research and may be useful for drug development); (2) peptides from conus snails; (3) peptides and polyamine toxins from spiders and wasps; and (4) peptides from scorpions.
Collapse
Affiliation(s)
- Márcia Renata Mortari
- Neurobiology and Venoms Laboratory, Department of Biology, School of Philosophy, Sciences and Literature, University of São Paulo Ribeirão Preto, Brazil
| | | | | | | |
Collapse
|
10
|
Borges A, García CC, Lugo E, Alfonzo MJ, Jowers MJ, Op den Camp HJM. Diversity of long-chain toxins in Tityus zulianus and Tityus discrepans venoms (Scorpiones, Buthidae): molecular, immunological, and mass spectral analyses. Comp Biochem Physiol C Toxicol Pharmacol 2006; 142:240-252. [PMID: 16356783 DOI: 10.1016/j.cbpc.2005.10.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Revised: 10/11/2005] [Accepted: 10/12/2005] [Indexed: 11/27/2022]
Abstract
In Venezuela, stings by Tityus zulianus scorpions produce cardiorespiratory arrest, whereas envenoming by Tityus discrepans involves gastrointestinal/pancreatic complications, suggesting structural and/or functional differences. We sought to compare their toxin repertoires through immunological, molecular, and mass spectral analyses. First, in vivo tests showed that neutralization of T. zulianus venom toxicity by the anti-T. discrepans antivenom was not complete. To compare T. discrepans and T. zulianus long-chain (sodium channel-active) toxins, their most toxic Sephadex G-50 fractions, TdII and TzII, were subjected to acid-urea PAGE, which showed differences in composition. Amplification of toxin-encoding mRNAs using a leader peptide-based oligonucleotide rendered cDNAs representing twelve T. discrepans and two T. zulianus distinct toxin transcripts, including only one shared component, indicating divergence between T. zulianus and T. discrepans 5' region-encoded, toxin signal peptides. A 3'-UTR polymorphism was also noticed among the transcripts encoding shared components Tz1 and Td4. MALDI-TOF MS profiling of TdII and TzII produced species-specific spectra, with seven of the individual masses matching those predicted by cDNA sequencing. Phylogenetic analysis showed that the unique T. zulianus transcript-encoded sequence, Tz2, is structurally related to Tityus serrulatus and Centruroides toxins. Together with previous reports, this work indicates that T. zulianus and T. discrepans toxin repertoires differ structurally and functionally.
Collapse
Affiliation(s)
- Adolfo Borges
- Sección de Biomembranas, Instituto de Medicina Experimental, Universidad Central de Venezuela, Caracas 1051, Venezuela.
| | - Carmen C García
- Sección de Biomembranas, Instituto de Medicina Experimental, Universidad Central de Venezuela, Caracas 1051, Venezuela
| | - Elizabeth Lugo
- Sección de Biomembranas, Instituto de Medicina Experimental, Universidad Central de Venezuela, Caracas 1051, Venezuela
| | - Marcelo J Alfonzo
- Sección de Biomembranas, Instituto de Medicina Experimental, Universidad Central de Venezuela, Caracas 1051, Venezuela
| | - Michael J Jowers
- Institute of Biomedical and Life Sciences, Division of Molecular Genetics, University of Glasgow, Glasgow G11 6NU, United Kingdom
| | - Huub J M Op den Camp
- Department of Microbiology, Faculty of Science, Radboud University Nijmegen, Tooernooiveld 1, Nijmegen, The Netherlands
| |
Collapse
|
11
|
Mortari MR, Cunha AOS, de Oliveira L, Vieira EB, Gelfuso EA, Coutinho-Netto J, Ferreira dos Santos W. Anticonvulsant and Behavioural Effects of the Denatured Venom of the Social Wasp Polybia occidentalis (Polistinae, Vespidae). Basic Clin Pharmacol Toxicol 2005; 97:289-95. [PMID: 16236140 DOI: 10.1111/j.1742-7843.2005.pto_137.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Several investigations demonstrate that neurotoxins isolated from venoms of spiders and wasps may exert specific and selective activity on structures of the mammalian CNS. In the present work we examine the neurological effects of the low molecular weight compounds of the denatured venom of the neotropical social wasp Polybia occidentalis in freely moving rats. Central administration of denatured venom decreased the duration of exploratory, elevation and grooming behaviours on the open field. Moreover, denatured venom inhibited convulsing action of bicuculline (ED50 57 microg/microl), picrotoxin (ED50 75 microg/microl) and kainic acid (ED50 44 microg/microl), although it was ineffective against pentylenetetrazole-induced seizures. Despite of its inhibitory activity, toxic effects on motor performance examined in the rotarod test were not found, not even in extremely high doses. Also, denatured venom moderately reduced the spontaneous locomotor activity at anticonvulsant doses. These findings may indicate that the denatured venom has anticonvulsant activity with scarce propensity to cause neurological side-effects. Further studies are necessary to isolate the active compound and establish its mechanism of action.
Collapse
Affiliation(s)
- Márcia Renata Mortari
- Neurobiology and Venoms Laboratory, Department of Biology, Faculty of Philosophy, Sciences and Literature, University of São Paulo, São Paulo, Brazil
| | | | | | | | | | | | | |
Collapse
|
12
|
del Río-Portilla F, Hernández-Marín E, Pimienta G, Coronas FV, Zamudio FZ, Rodríguez de la Vega RC, Wanke E, Possani LD. NMR solution structure of Cn12, a novel peptide from the Mexican scorpion Centruroides noxius with a typical beta-toxin sequence but with alpha-like physiological activity. ACTA ACUST UNITED AC 2004; 271:2504-16. [PMID: 15182366 DOI: 10.1111/j.1432-1033.2004.04181.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Cn12 isolated from the venom of the scorpion Centruroides noxius has 67 amino-acid residues, closely packed with four disulfide bridges. Its primary structure and disulfide bridges were determined. Cn12 is not lethal to mammals and arthropods in vivo at doses up to 100 microg per animal. Its 3D structure was determined by proton NMR using 850 distance constraints, 36 phi angles derived from 36 coupling constants obtained by two different methods, and 22 hydrogen bonds. The overall structure has a two and half turn alpha-helix (residues 24-32), three strands of antiparallel beta-sheet (residues 2-4, 37-40 and 45-48), and a type II turn (residues 41-44). The amino-acid sequence of Cn12 resembles the beta scorpion toxin class, although patch-clamp experiments showed the induction of supplementary slow inactivation of Na(+) channels in F-11 cells (mouse neuroblastoma N18TG-2 x rat DRG2), which means that it behaves more like an alpha scorpion toxin. This behaviour prompted us to analyse Na(+) channel binding sites using information from 112 Na(+) channel gene clones available in the literature, focusing on the extracytoplasmic loops of the S5-S6 transmembrane segments of domain I and the S3-S4 segments of domain IV, sites considered to be responsible for binding alpha scorpion toxins.
Collapse
|