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de Melo ET, Estrela AB, Santos ECG, Machado PRL, Farias KJS, Torres TM, Carvalho E, Lima JPMS, Silva-Júnior AA, Barbosa EG, Fernandes-Pedrosa MDF. Structural characterization of a novel peptide with antimicrobial activity from the venom gland of the scorpion Tityus stigmurus: Stigmurin. Peptides 2015; 68:3-10. [PMID: 25805002 DOI: 10.1016/j.peptides.2015.03.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 03/02/2015] [Accepted: 03/05/2015] [Indexed: 01/05/2023]
Abstract
A new antimicrobial peptide, herein named Stigmurin, was selected based on a transcriptomic analysis of the Brazilian yellow scorpion Tityus stigmurus venom gland, an underexplored source for toxic peptides with possible biotechnological applications. Stigmurin was investigated in silico, by circular dichroism (CD) spectroscopy, and in vitro. The CD spectra suggested that this peptide interacts with membranes, changing its conformation in the presence of an amphipathic environment, with predominance of random coil and beta-sheet structures. Stigmurin exhibited antibacterial and antifungal activity, with minimal inhibitory concentrations ranging from 8.7 to 69.5μM. It was also showed that Stigmurin is toxic against SiHa and Vero E6 cell lines. The results suggest that Stigmurin can be considered a potential anti-infective drug.
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Affiliation(s)
- Edinara Targino de Melo
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil
| | - Andréia Bergamo Estrela
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil
| | | | | | | | - Taffarel Melo Torres
- Departamento de Ciências Animais, Universidade Federal Rural do Semi-Árido, Mossoró, RN, Brazil
| | - Enéas Carvalho
- Centro de Biotecnologia, Instituto Butantan, São Paulo, SP, Brazil
| | | | - Arnóbio Antonio Silva-Júnior
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil
| | | | - Matheus de Freitas Fernandes-Pedrosa
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil; Programa de Pós-Graduação em Bioquímica, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.
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52
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Luna-Ramírez K, Quintero-Hernández V, Juárez-González VR, Possani LD. Whole Transcriptome of the Venom Gland from Urodacus yaschenkoi Scorpion. PLoS One 2015; 10:e0127883. [PMID: 26020943 PMCID: PMC4447460 DOI: 10.1371/journal.pone.0127883] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 04/20/2015] [Indexed: 12/24/2022] Open
Abstract
Australian scorpion venoms have been poorly studied, probably because they do not pose an evident threat to humans. In addition, the continent has other medically important venomous animals capable of causing serious health problems. Urodacus yaschenkoi belongs to the most widely distributed family of Australian scorpions (Urodacidae) and it is found all over the continent, making it a useful model system for studying venom composition and evolution. This communication reports the whole set of mRNA transcripts produced by the venom gland. U. yaschenkoi venom is as complex as its overseas counterparts. These transcripts certainly code for several components similar to known scorpion venom components, such as: alpha-KTxs, beta-KTxs, calcins, protease inhibitors, antimicrobial peptides, sodium-channel toxins, toxin-like peptides, allergens, La1-like, hyaluronidases, ribosomal proteins, proteasome components and proteins related to cellular processes. A comparison with the venom gland transcriptome of Centruroides noxius (Buthidae) showed that these two scorpions have similar components related to biological processes, although important differences occur among the venom toxins. In contrast, a comparison with sequences reported for Urodacus manicatus revealed that these two Urodacidae species possess the same subfamily of scorpion toxins. A comparison with sequences of an U. yaschenkoi cDNA library previously reported by our group showed that both techniques are reliable for the description of the venom components, but the whole transcriptome generated with Next Generation Sequencing platform provides sequences of all transcripts expressed. Several of which were identified in the proteome, but many more transcripts were identified including uncommon transcripts. The information reported here constitutes a reference for non-Buthidae scorpion venoms, providing a comprehensive view of genes that are involved in venom production. Further, this work identifies new putative bioactive compounds that could be used to seed research into new pharmacological compounds and increase our understanding of the function of different ion channels.
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Affiliation(s)
- Karen Luna-Ramírez
- Australian Venom Research Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Victoria, Australia
| | - Verónica Quintero-Hernández
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Víctor Rivelino Juárez-González
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Lourival D. Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
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53
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Kuzmenkov AI, Vassilevski AA, Kudryashova KS, Nekrasova OV, Peigneur S, Tytgat J, Feofanov AV, Kirpichnikov MP, Grishin EV. Variability of Potassium Channel Blockers in Mesobuthus eupeus Scorpion Venom with Focus on Kv1.1: AN INTEGRATED TRANSCRIPTOMIC AND PROTEOMIC STUDY. J Biol Chem 2015; 290:12195-209. [PMID: 25792741 DOI: 10.1074/jbc.m115.637611] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Indexed: 12/21/2022] Open
Abstract
The lesser Asian scorpion Mesobuthus eupeus (Buthidae) is one of the most widely spread and dispersed species of the Mesobuthus genus, and its venom is actively studied. Nevertheless, a considerable amount of active compounds is still under-investigated due to the high complexity of this venom. Here, we report a comprehensive analysis of putative potassium channel toxins (KTxs) from the cDNA library of M. eupeus venom glands, and we compare the deduced KTx structures with peptides purified from the venom. For the transcriptome analysis, we used conventional tools as well as a search for structural motifs characteristic of scorpion venom components in the form of regular expressions. We found 59 candidate KTxs distributed in 30 subfamilies and presenting the cysteine-stabilized α/β and inhibitor cystine knot types of fold. M. eupeus venom was then separated to individual components by multistage chromatography. A facile fluorescent system based on the expression of the KcsA-Kv1.1 hybrid channels in Escherichia coli and utilization of a labeled scorpion toxin was elaborated and applied to follow Kv1.1 pore binding activity during venom separation. As a result, eight high affinity Kv1.1 channel blockers were identified, including five novel peptides, which extend the panel of potential pharmacologically important Kv1 ligands. Activity of the new peptides against rat Kv1.1 channel was confirmed (IC50 in the range of 1-780 nm) by the two-electrode voltage clamp technique using a standard Xenopus oocyte system. Our integrated approach is of general utility and efficiency to mine natural venoms for KTxs.
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Affiliation(s)
- Alexey I Kuzmenkov
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Alexander A Vassilevski
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia,
| | - Kseniya S Kudryashova
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia, the Biological Faculty, Lomonosov Moscow State University, Moscow 119992, Russia, and
| | - Oksana V Nekrasova
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Steve Peigneur
- the Laboratory of Toxicology and Pharmacology, University of Leuven, Leuven 3000, Belgium
| | - Jan Tytgat
- the Laboratory of Toxicology and Pharmacology, University of Leuven, Leuven 3000, Belgium
| | - Alexey V Feofanov
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia, the Biological Faculty, Lomonosov Moscow State University, Moscow 119992, Russia, and
| | - Mikhail P Kirpichnikov
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia, the Biological Faculty, Lomonosov Moscow State University, Moscow 119992, Russia, and
| | - Eugene V Grishin
- From the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
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The transcriptome recipe for the venom cocktail of Tityus bahiensis scorpion. Toxicon 2015; 95:52-61. [DOI: 10.1016/j.toxicon.2014.12.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/13/2014] [Accepted: 12/27/2014] [Indexed: 12/23/2022]
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Harrison PL, Abdel-Rahman MA, Miller K, Strong PN. Antimicrobial peptides from scorpion venoms. Toxicon 2014; 88:115-37. [PMID: 24951876 PMCID: PMC7111748 DOI: 10.1016/j.toxicon.2014.06.006] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/28/2014] [Accepted: 06/10/2014] [Indexed: 12/01/2022]
Abstract
The need for new antimicrobial agents is becoming one of the most urgent requirements in modern medicine. The venoms of many different species are rich sources of biologically active components and various therapeutic agents have been characterized including antimicrobial peptides (AMPs). Due to their potent activity, low resistance rates and unique mode of action, AMPs have recently received much attention. This review focuses on AMPs from the venoms of scorpions and examines all classes of AMPs found to date. It gives details of their biological activities with reference to peptide structure. The review examines the mechanism of action of AMPs and with this information, suggests possible mechanisms of action of less well characterised peptides. Finally, the review examines current and future trends of scorpion AMP research, by discussing recent successes obtained through proteomic and transcriptomic approaches. In-depth analysis of AMPs from scorpion venom. Focus on biological activity and structure – function relationships. Discussion of possible mechanisms of action. Future strategies for further mining of bioactive compounds from venoms.
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Affiliation(s)
- Patrick L Harrison
- Biomedical Research Centre, Biosciences Division, Sheffield Hallam University, Sheffield S1 1WB, UK
| | - Mohamed A Abdel-Rahman
- Biomedical Research Centre, Biosciences Division, Sheffield Hallam University, Sheffield S1 1WB, UK; Zoology Department, Faculty of Science, Suez Canal University, Ismailia 41522, Egypt
| | - Keith Miller
- Biomedical Research Centre, Biosciences Division, Sheffield Hallam University, Sheffield S1 1WB, UK
| | - Peter N Strong
- Biomedical Research Centre, Biosciences Division, Sheffield Hallam University, Sheffield S1 1WB, UK.
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Mille BG, Peigneur S, Diego-García E, Predel R, Tytgat J. Partial transcriptomic profiling of toxins from the venom gland of the scorpion Parabuthus stridulus. Toxicon 2014; 83:75-83. [DOI: 10.1016/j.toxicon.2014.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 02/05/2014] [Accepted: 03/04/2014] [Indexed: 01/02/2023]
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57
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Cao Z, Di Z, Wu Y, Li W. Overview of scorpion species from China and their toxins. Toxins (Basel) 2014; 6:796-815. [PMID: 24577583 PMCID: PMC3968362 DOI: 10.3390/toxins6030796] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 01/16/2014] [Accepted: 01/18/2014] [Indexed: 12/29/2022] Open
Abstract
Scorpions are one of the most ancient groups of terrestrial animals. They have maintained a steady morphology over more than 400 million years of evolution. Their venom arsenals for capturing prey and defending against predators may play a critical role in their ancient and conservative appearance. In the current review, we present the scorpion fauna of China: 53 species covering five families and 12 genera. We also systematically list toxins or genes from Chinese scorpion species, involving eight species covering four families. Furthermore, we review the diverse functions of typical toxins from Chinese scorpion species, involving Na+ channel modulators, K+ channel blockers, antimicrobial peptides and protease inhibitors. Using scorpion species and their toxins from China as an example, we build the bridge between scorpion species and their toxins, which helps us to understand the molecular and functional diversity of scorpion venom arsenal, the dynamic and functional evolution of scorpion toxins, and the potential relationships of scorpion species and their toxins.
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Affiliation(s)
- Zhijian Cao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Zhiyong Di
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Yingliang Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Wenxin Li
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
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Quintero-Hernández V, Jiménez-Vargas J, Gurrola G, Valdivia H, Possani L. Scorpion venom components that affect ion-channels function. Toxicon 2013; 76:328-42. [PMID: 23891887 PMCID: PMC4089097 DOI: 10.1016/j.toxicon.2013.07.012] [Citation(s) in RCA: 193] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 07/16/2013] [Indexed: 12/31/2022]
Abstract
The number and types of venom components that affect ion-channel function are reviewed. These are the most important venom components responsible for human intoxication, deserving medical attention, often requiring the use of specific anti-venoms. Special emphasis is given to peptides that recognize Na(+)-, K(+)- and Ca(++)-channels of excitable cells. Knowledge generated by direct isolation of peptides from venom and components deduced from cloned genes, whose amino acid sequences are deposited into databanks are nowadays in the order of 1.5 thousands, out of an estimate biodiversity closed to 300,000. Here the diversity of components is briefly reviewed with mention to specific references. Structural characteristic are discussed with examples taken from published work. The principal mechanisms of action of the three different types of peptides are also reviewed. Na(+)-channel specific venom components usually are modifier of the open and closing kinetic mechanisms of the ion-channels, whereas peptides affecting K(+)-channels are normally pore blocking agents. The Ryanodine Ca(++)-channel specific peptides are known for causing sub-conducting stages of the channels conductance and some were shown to be able to internalize penetrating inside the muscle cells.
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Affiliation(s)
- V. Quintero-Hernández
- Department of Molecular Medicine and Bioprocesses, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Avenida Universidad, 2001, Apartado Postal 510-3, Cuernavaca 62210, Morelos, Mexico
| | - J.M. Jiménez-Vargas
- Department of Molecular Medicine and Bioprocesses, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Avenida Universidad, 2001, Apartado Postal 510-3, Cuernavaca 62210, Morelos, Mexico
| | - G.B. Gurrola
- Department of Molecular Medicine and Bioprocesses, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Avenida Universidad, 2001, Apartado Postal 510-3, Cuernavaca 62210, Morelos, Mexico
- Cardiovascular Center 2139, Michigan University, Ann Arbor, MI 48109-5644, U.S.A
| | - H.H.F. Valdivia
- Cardiovascular Center 2139, Michigan University, Ann Arbor, MI 48109-5644, U.S.A
| | - L.D. Possani
- Department of Molecular Medicine and Bioprocesses, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Avenida Universidad, 2001, Apartado Postal 510-3, Cuernavaca 62210, Morelos, Mexico
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59
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Abdel-Rahman MA, Quintero-Hernandez V, Possani LD. Venom proteomic and venomous glands transcriptomic analysis of the Egyptian scorpion Scorpio maurus palmatus (Arachnida: Scorpionidae). Toxicon 2013; 74:193-207. [DOI: 10.1016/j.toxicon.2013.08.064] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 08/20/2013] [Accepted: 08/22/2013] [Indexed: 12/21/2022]
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von Reumont BM, Blanke A, Richter S, Alvarez F, Bleidorn C, Jenner RA. The first venomous crustacean revealed by transcriptomics and functional morphology: remipede venom glands express a unique toxin cocktail dominated by enzymes and a neurotoxin. Mol Biol Evol 2013; 31:48-58. [PMID: 24132120 PMCID: PMC3879455 DOI: 10.1093/molbev/mst199] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Animal venoms have evolved many times. Venomous species are especially common in three of the four main groups of arthropods (Chelicerata, Myriapoda, and Hexapoda), which together represent tens of thousands of species of venomous spiders, scorpions, centipedes, and hymenopterans. Surprisingly, despite their great diversity of body plans, there is no unambiguous evidence that any crustacean is venomous. We provide the first conclusive evidence that the aquatic, blind, and cave-dwelling remipede crustaceans are venomous and that venoms evolved in all four major arthropod groups. We produced a three-dimensional reconstruction of the venom delivery apparatus of the remipede Speleonectes tulumensis, showing that remipedes can inject venom in a controlled manner. A transcriptomic profile of its venom glands shows that they express a unique cocktail of transcripts coding for known venom toxins, including a diversity of enzymes and a probable paralytic neurotoxin very similar to one described from spider venom. We screened a transcriptomic library obtained from whole animals and identified a nontoxin paralog of the remipede neurotoxin that is not expressed in the venom glands. This allowed us to reconstruct its probable evolutionary origin and underlines the importance of incorporating data derived from nonvenom gland tissue to elucidate the evolution of candidate venom proteins. This first glimpse into the venom of a crustacean and primitively aquatic arthropod reveals conspicuous differences from the venoms of other predatory arthropods such as centipedes, scorpions, and spiders and contributes valuable information for ultimately disentangling the many factors shaping the biology and evolution of venoms and venomous species.
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Affiliation(s)
- Björn M von Reumont
- Department of Life Sciences, The Natural History Museum, London, United Kingdom
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61
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Venancio EJ, Portaro FC, Kuniyoshi AK, Carvalho DC, Pidde-Queiroz G, Tambourgi DV. Enzymatic properties of venoms from Brazilian scorpions of Tityus genus and the neutralisation potential of therapeutical antivenoms. Toxicon 2013; 69:180-90. [DOI: 10.1016/j.toxicon.2013.02.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 01/23/2013] [Accepted: 02/19/2013] [Indexed: 01/16/2023]
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62
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Valdez-Velázquez LL, Quintero-Hernández V, Romero-Gutiérrez MT, Coronas FIV, Possani LD. Mass fingerprinting of the venom and transcriptome of venom gland of scorpion Centruroides tecomanus. PLoS One 2013; 8:e66486. [PMID: 23840487 PMCID: PMC3688770 DOI: 10.1371/journal.pone.0066486] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 05/06/2013] [Indexed: 01/02/2023] Open
Abstract
Centruroides tecomanus is a Mexican scorpion endemic of the State of Colima, that causes human fatalities. This communication describes a proteome analysis obtained from milked venom and a transcriptome analysis from a cDNA library constructed from two pairs of venom glands of this scorpion. High perfomance liquid chromatography separation of soluble venom produced 80 fractions, from which at least 104 individual components were identified by mass spectrometry analysis, showing to contain molecular masses from 259 to 44,392 Da. Most of these components are within the expected molecular masses for Na+- and K+-channel specific toxic peptides, supporting the clinical findings of intoxication, when humans are stung by this scorpion. From the cDNA library 162 clones were randomly chosen, from which 130 sequences of good quality were identified and were clustered in 28 contigs containing, each, two or more expressed sequence tags (EST) and 49 singlets with only one EST. Deduced amino acid sequence analysis from 53% of the total ESTs showed that 81% (24 sequences) are similar to known toxic peptides that affect Na+-channel activity, and 19% (7 unique sequences) are similar to K+-channel especific toxins. Out of the 31 sequences, at least 8 peptides were confirmed by direct Edman degradation, using components isolated directly from the venom. The remaining 19%, 4%, 4%, 15% and 5% of the ESTs correspond respectively to proteins involved in cellular processes, antimicrobial peptides, venom components, proteins without defined function and sequences without similarity in databases. Among the cloned genes are those similar to metalloproteinases.
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Affiliation(s)
| | | | | | - Fredy I. V. Coronas
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Lourival D. Possani
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
- * E-mail:
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63
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Almeida DD, Torres TM, Barbosa EG, Lima JPMS, de Freitas Fernandes-Pedrosa M. Molecular approaches for structural characterization of a new potassium channel blocker from Tityus stigmurus venom: cDNA cloning, homology modeling, dynamic simulations and docking. Biochem Biophys Res Commun 2012. [PMID: 23200836 DOI: 10.1016/j.bbrc.2012.11.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Potassium channels are involved in the maintenance of resting membrane potential, control of cardiac and neuronal excitability, neurotransmitters release, muscle contractility and hormone secretion. The Tityus stigmurus scorpion is widely distributed in Northeastern Brazil and known to cause severe human envenomations, inducing pain, hypoesthesia, edema, erythema, paresthesia, headaches and vomiting. Most potassium channel blocking peptides that have been purified from scorpion venoms contain 30-40 amino acids with three or four disulfide bridges. These peptides belong to α-KTx subfamily. On the other hand, the β-KTx subfamily is poorly characterized, though it is very representative in some scorpion venoms. A transcriptomic approach of T.stigmurus scorpions developed by our group revealed the repertoire of possible molecules present in the venom, including many toxins of the β-KTx subfamily. One of the ESTs found, named TSTI0003C has a cDNA sequence of 538 bp codifying a mature protein with 47 amino acid residues, corresponding to 5299 Da. This β-KTx peptide is a new member of the BmTXKβ-related toxins, and was here named TstKMK. The three-dimensional structure of this potassium channel toxin of the T. stigmurus scorpion was obtained by computational modeling and refined by molecular dynamic simulations. Furthermore, we have made docking simulations using a Shaker kV-1.2 potassium channel from rats as receptor model and proposed which amino acid residues and interactions could be involved in its blockade.
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Affiliation(s)
- Diego Dantas Almeida
- Laboratório de Tecnologia e Biotecnologia Farmacêutica, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil
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Alvarenga ER, Mendes TM, Magalhaes BF, Siqueira FF, Dantas AE, Barroca TM, Horta CC, Kalapothakis E. Transcriptome analysis of the <i>Tityus serrulatus</i> scorpion venom gland. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/ojgen.2012.24027] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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