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Phulera S, Dickson CJ, Schwalen CJ, Khoshouei M, Cassell SJ, Sun Y, Condos T, Whicher J, Weihofen WA. Scorpion α-toxin LqhαIT specifically interacts with a glycan at the pore domain of voltage-gated sodium channels. Structure 2024:S0969-2126(24)00284-3. [PMID: 39181123 DOI: 10.1016/j.str.2024.07.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 06/13/2024] [Accepted: 07/30/2024] [Indexed: 08/27/2024]
Abstract
Voltage-gated sodium (Nav) channels sense membrane potential and drive cellular electrical activity. The deathstalker scorpion α-toxin LqhαIT exerts a strong action potential prolonging effect on Nav channels. To elucidate the mechanism of action of LqhαIT, we determined a 3.9 Å cryoelectron microscopy (cryo-EM) structure of LqhαIT in complex with the Nav channel from Periplaneta americana (NavPas). We found that LqhαIT binds to voltage sensor domain 4 and traps it in an "S4 down" conformation. The functionally essential C-terminal epitope of LqhαIT forms an extensive interface with the glycan scaffold linked to Asn330 of NavPas that augments a small protein-protein interface between NavPas and LqhαIT. A combination of molecular dynamics simulations, structural comparisons, and prior mutagenesis experiments demonstrates the functional importance of this toxin-glycan interaction. These findings establish a structural basis for the specificity achieved by scorpion α-toxins and reveal the conserved glycan as an essential component of the toxin-binding epitope.
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Affiliation(s)
- Swastik Phulera
- Discovery Sciences, Novartis Biomedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Callum J Dickson
- Global Discovery Chemistry, Novartis Biomedical Research, 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Christopher J Schwalen
- Global Discovery Chemistry, Novartis Biomedical Research, 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Maryam Khoshouei
- Discovery Sciences, Novartis Biomedical Research, Novartis Pharma AG, Basel, Switzerland
| | - Samantha J Cassell
- Discovery Sciences, Novartis Biomedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Yishan Sun
- Neuroscience, Novartis Biomedical Research, 22 Windsor St, Cambridge, MA 02139, USA
| | - Tara Condos
- Discovery Sciences, Novartis Biomedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Jonathan Whicher
- Discovery Sciences, Novartis Biomedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA.
| | - Wilhelm A Weihofen
- Discovery Sciences, Novartis Biomedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA.
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2
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Wang D, Herzig V, Dekan Z, Rosengren KJ, Payne CD, Hasan MM, Zhuang J, Bourinet E, Ragnarsson L, Alewood PF, Lewis RJ. Novel Scorpion Toxin ω-Buthitoxin-Hf1a Selectively Inhibits Calcium Influx via Ca V3.3 and Ca V3.2 and Alleviates Allodynia in a Mouse Model of Acute Postsurgical Pain. Int J Mol Sci 2024; 25:4745. [PMID: 38731963 PMCID: PMC11084959 DOI: 10.3390/ijms25094745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/13/2024] Open
Abstract
Venom peptides have evolved to target a wide range of membrane proteins through diverse mechanisms of action and structures, providing promising therapeutic leads for diseases, including pain, epilepsy, and cancer, as well as unique probes of ion channel structure-function. In this work, a high-throughput FLIPR window current screening assay on T-type CaV3.2 guided the isolation of a novel peptide named ω-Buthitoxin-Hf1a from scorpion Hottentotta franzwerneri crude venom. At only 10 amino acid residues with one disulfide bond, it is not only the smallest venom peptide known to target T-type CaVs but also the smallest structured scorpion venom peptide yet discovered. Synthetic Hf1a peptides were prepared with C-terminal amidation (Hf1a-NH2) or a free C-terminus (Hf1a-OH). Electrophysiological characterization revealed Hf1a-NH2 to be a concentration-dependent partial inhibitor of CaV3.2 (IC50 = 1.18 μM) and CaV3.3 (IC50 = 0.49 μM) depolarized currents but was ineffective at CaV3.1. Hf1a-OH did not show activity against any of the three T-type subtypes. Additionally, neither form showed activity against N-type CaV2.2 or L-type calcium channels. The three-dimensional structure of Hf1a-NH2 was determined using NMR spectroscopy and used in docking studies to predict its binding site at CaV3.2 and CaV3.3. As both CaV3.2 and CaV3.3 have been implicated in peripheral pain signaling, the analgesic potential of Hf1a-NH2 was explored in vivo in a mouse model of incision-induced acute post-surgical pain. Consistent with this role, Hf1a-NH2 produced antiallodynia in both mechanical and thermal pain.
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Affiliation(s)
- Dan Wang
- Department of Chinese Medicine and Pharmacy, School of Pharmacy, Jiangsu University, Zhenjiang 212013, China;
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia (L.R.); (P.F.A.)
| | - Volker Herzig
- Centre for Bioinnovation, University of the Sunshine Coast, Sippy Downs, QLD 4556, Australia;
- School of Science, Technology and Engineering, University of the Sunshine Coast, Sippy Downs, QLD 4556, Australia
| | - Zoltan Dekan
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia (L.R.); (P.F.A.)
| | - K. Johan Rosengren
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia; (K.J.R.); (C.D.P.)
| | - Colton D. Payne
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia; (K.J.R.); (C.D.P.)
| | - Md. Mahadhi Hasan
- Pharmacy Discipline, Life Science School, Khulna University, Khulna 9208, Bangladesh;
| | - Jiajie Zhuang
- Department of Chinese Medicine and Pharmacy, School of Pharmacy, Jiangsu University, Zhenjiang 212013, China;
| | - Emmanuel Bourinet
- Institute of Functional Genomics, Montpellier University, CNRS, INSERM, 34090 Montpellier, France;
| | - Lotten Ragnarsson
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia (L.R.); (P.F.A.)
| | - Paul F. Alewood
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia (L.R.); (P.F.A.)
| | - Richard J. Lewis
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia (L.R.); (P.F.A.)
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3
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Dashevsky D, Rodriguez J. A Short Review of the Venoms and Toxins of Spider Wasps (Hymenoptera: Pompilidae). Toxins (Basel) 2021; 13:toxins13110744. [PMID: 34822528 PMCID: PMC8622703 DOI: 10.3390/toxins13110744] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/07/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022] Open
Abstract
Parasitoid wasps represent the plurality of venomous animals, but have received extremely little research in proportion to this taxonomic diversity. The lion’s share of investigation into insect venoms has focused on eusocial hymenopterans, but even this small sampling shows great promise for the development of new active substances. The family Pompilidae is known as the spider wasps because of their reproductive habits which include hunting for spiders, delivering a paralyzing sting, and entombing them in burrows with one of the wasp’s eggs to serve as food for the developing larva. The largest members of this family, especially the tarantula hawks of the genus Pepsis, have attained notoriety for their large size, dramatic coloration, long-term paralysis of their prey, and incredibly painful defensive stings. In this paper we review the existing research regarding the composition and function of pompilid venoms, discuss parallels from other venom literatures, identify possible avenues for the adaptation of pompilid toxins towards human purposes, and future directions of inquiry for the field.
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4
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Li YL, Qu Q, Qi YK, Liu L, Wang KW, Liu Y, Fang GM. Comparison of different strategies towards the chemical synthesis of long-chain scorpion toxin AaH-II. J Pept Sci 2021; 28:e3365. [PMID: 34467600 DOI: 10.1002/psc.3365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/02/2021] [Accepted: 08/05/2021] [Indexed: 11/08/2022]
Abstract
Long-chain scorpion toxin AaH-II isolated from Androctonus australis Hector can selectively inhibit mammalian voltage-gated sodium ion channel Nav 1.7 responsible for pain sensation. Efficient chemical synthesis of AaH-II and its derivatives is beneficial to the study of the function and mechanism of Nav 1.7 and the development of potential peptide inhibitors. Herein, we compared three different strategies, namely, direct solid-phase peptide synthesis, hydrazide-based two-segment native chemical ligation, and hydrazide-based three-segment native chemical ligation for the synthesis of AaH-II. The hydrazide-based two-segment native chemical ligation affords the target toxin with the optimal efficiency, which provides a practically robust procedure for the preparation of tool molecules derived from AaH-II to study the biological functions and modulation of Nav 1.7. Our work highlights the importance of selecting suitable segment condensation approach in the chemical synthesis of protein toxins.
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Affiliation(s)
- Yu-Lei Li
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China.,Department of Pharmacology, School of Pharmacy, Qingdao University, Qingdao, China
| | - Qian Qu
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China.,Department of Health Sciences, Institutes of Physical Science and Information Technology, Anhui University, Hefei, China
| | - Yun-Kun Qi
- Department of Pharmacology, School of Pharmacy, Qingdao University, Qingdao, China
| | - Lei Liu
- Tsinghua-Peking Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China
| | - Ke Wei Wang
- Department of Pharmacology, School of Pharmacy, Qingdao University, Qingdao, China
| | - Yani Liu
- Department of Pharmacology, School of Pharmacy, Qingdao University, Qingdao, China
| | - Ge-Min Fang
- Department of Health Sciences, Institutes of Physical Science and Information Technology, Anhui University, Hefei, China
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5
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Mineev KS, Kuzmenkov AI, Arseniev AS, Vassilevski AA. Structure of MeuNaTxα-1 toxin from scorpion venom highlights the importance of the nest motif. Proteins 2021; 89:1055-1060. [PMID: 33713480 DOI: 10.1002/prot.26074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 01/04/2021] [Accepted: 03/04/2021] [Indexed: 11/08/2022]
Abstract
Old world scorpions produce an abundance of toxins called α-NaTx, which interfere with the fast inactivation of voltage-gated sodium channels. Their selectivity to channels of mammals or insects depends on a part of toxin named the specificity module. We report here the spatial structure of a major and broadly active toxin MeuNaTxα-1 from the venom of Mesobuthus eupeus. Notably, its specificity module is markedly different from other α-NaTx with known 3D structure. Close inspection shows that its conformation is a result of an interplay between protein motifs such as the nest and niche, which eventually shape α-NaTx structural diversity.
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Affiliation(s)
- Konstantin S Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
- Moscow Institute of Physics and Technology (State University), Moscow, Russian Federation
| | - Alexey I Kuzmenkov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Alexander S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
- Moscow Institute of Physics and Technology (State University), Moscow, Russian Federation
| | - Alexander A Vassilevski
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
- Moscow Institute of Physics and Technology (State University), Moscow, Russian Federation
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6
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Richard SA, Kampo S, Sackey M, Hechavarria ME, Buunaaim ADB. The Pivotal Potentials of Scorpion Buthus Martensii Karsch-Analgesic-Antitumor Peptide in Pain Management and Cancer. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2020; 2020:4234273. [PMID: 33178316 PMCID: PMC7647755 DOI: 10.1155/2020/4234273] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/13/2020] [Accepted: 10/20/2020] [Indexed: 01/26/2023]
Abstract
Scorpion Buthus martensii Karsch -analgesic-antitumor peptide (BmK AGAP) has been used to treat diseases like tetanus, tuberculosis, apoplexy, epilepsy, spasm, migraine headaches, rheumatic pain, and cancer in China. AGAP is a distinctive long-chain scorpion toxin with a molecular mass of 7142 Da and composed of 66 amino acids cross-linked by four disulfide bridges. Voltage-gated sodium channels (VGSCs) are present in excitable membranes and partakes in essential roles in action potentials generation as compared to the significant function of voltage-gated calcium channels (VGCCs). A total of nine genes (Nav1.1-Nav1.9) have been recognized to encode practical sodium channel isoforms. Nav1.3, Nav1.7, Nav1.8, and Nav1.9 have been recognized as potential targets for analgesics. Nav1.8 and Nav1.9 are associated with nociception initiated by inflammation signals in the neuronal pain pathway, while Nav1.8 is fundamental for neuropathic pain at low temperatures. AGAP has a sturdy inhibitory influence on both viscera and soma pain. AGAP potentiates the effects of MAPK inhibitors on neuropathic as well as inflammation-associated pain. AGAP downregulates the secretion of phosphorylated p38, phosphorylated JNK, and phosphorylated ERK 1/2 in vitro. AGAP has an analgesic activity which may be an effective therapeutic agent for pain management because of its downregulation of PTX3 via NF-κB and Wnt/beta-catenin signaling pathway. In cancers like colon cancer, breast cancer, lymphoma, and glioma, rAGAP was capable of blocking the proliferation. Thus, AGAP is a promising therapy for these tumors. Nevertheless, research is needed with other tumors.
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Affiliation(s)
- Seidu A. Richard
- Department of Medicine, Princefield University, P.O. Box MA128, Ho, Ghana
| | - Sylvanus Kampo
- Department of Anesthesia and Critical Care, School of Medicine, University of Health and Allied Sciences, Ho, Ghana
| | - Marian Sackey
- Department of Pharmacy, Ho Teaching Hospital, P.O. Box MA-374, Ho, Ghana
| | | | - Alexis D. B. Buunaaim
- Department of Surgery, School of Medicine and Health Science, University for Development Studies, Tamale, Ghana
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7
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Zhu L, Gao B, Yuan S, Zhu S. Scorpion Toxins: Positive Selection at a Distal Site Modulates Functional Evolution at a Bioactive Site. Mol Biol Evol 2019; 36:365-375. [PMID: 30566652 PMCID: PMC6367975 DOI: 10.1093/molbev/msy223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The bioactive sites of proteins are those that directly interact with their targets. In many immunity- and predation-related proteins, they frequently experience positive selection for dealing with the changes of their targets from competitors. However, some sites that are far away from the interface between proteins and their targets are also identified to evolve under positive selection. Here, we explore the evolutionary implication of such a site in scorpion α-type toxins affecting sodium (Na+) channels (abbreviated as α-ScNaTxs) using a combination of experimental and computational approaches. We found that despite no direct involvement in interaction with Na+ channels, mutations at this site by different types of amino acids led to toxicity change on both rats and insects in three α-ScNaTxs, accompanying differential effects on their structures. Molecular dynamics simulations indicated that the mutations changed the conformational dynamics of the positively selected bioactive site-containing functional regions by allosteric communication, suggesting a potential evolutionary correlation between these bioactive sites and the distant nonbioactive site. Our results reveal for the first time the cause of fast evolution at nonbioactive sites of scorpion neurotoxins, which is presumably to adapt to the change of their bioactive sites through coevolution to maintain an active conformation for channel binding. This might aid rational design of scorpion Na+ channel toxins with improved phyletic selectivity via modification of a distant nonbioactive site.
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Affiliation(s)
- Limei Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, China.,Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Bin Gao
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
| | - Shouli Yuan
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
| | - Shunyi Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
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8
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Kuldyushev NA, Mineev KS, Berkut AA, Peigneur S, Arseniev AS, Tytgat J, Grishin EV, Vassilevski AA. Refined structure of BeM9 reveals arginine hand, an overlooked structural motif in scorpion toxins affecting sodium channels. Proteins 2018; 86:1117-1122. [DOI: 10.1002/prot.25583] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 05/27/2018] [Accepted: 07/04/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Nikita A. Kuldyushev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Moscow Russia
| | - Konstantin S. Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Moscow Russia
| | - Antonina A. Berkut
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Moscow Russia
| | - Steve Peigneur
- Toxicology and Pharmacology; University of Leuven; Leuven Belgium
| | - Alexander S. Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Moscow Russia
| | - Jan Tytgat
- Toxicology and Pharmacology; University of Leuven; Leuven Belgium
| | - Eugene V. Grishin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
| | - Alexander A. Vassilevski
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Moscow Russia
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9
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The role of the arginine residue in site RC for the analgesic activity of the recombinant Chinese scorpion Buthus martensii Karsch, BmK AGP-SYPU1. Comput Biol Chem 2018; 74:247-252. [PMID: 29665474 DOI: 10.1016/j.compbiolchem.2018.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/03/2018] [Accepted: 04/08/2018] [Indexed: 01/05/2023]
Abstract
Scorpion venom is composed of a large number of bioactive peptides which display important pharmacological activities. In this study we have carried out a study of the functional role of the arginine residue at position 58 in the site RC comprising the reverse turn (8-12) and C-terminal residues 58-64. A polymerase chain reaction was used to substitute this arginine residue with a single amino acid such as alanine, glycine and lysine. The mutants were expressed in soluble form in E. coli, and purified by affinity chromatography. After target peptide purity identification, the recombinant peptides underwent a circular dichroism analysis and a study of their analgesic activity in mice. The results indicated that a single residue modification can affect the pharmacological activity. Our efforts establish a sound basis for further study of the structure-function determinants of the analgesic effect.
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10
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Kuldyushev NA, Berkut AA, Peigneur S, Tytgat J, Grishin EV, Vassilevski AA. Design of sodium channel ligands with defined selectivity - a case study in scorpion alpha-toxins. FEBS Lett 2017; 591:3414-3420. [DOI: 10.1002/1873-3468.12839] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 08/31/2017] [Accepted: 08/31/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Nikita A. Kuldyushev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Russia
| | - Antonina A. Berkut
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
- Moscow Institute of Physics and Technology (State University); Russia
| | - Steve Peigneur
- Toxicology and Pharmacology; University of Leuven; Belgium
| | - Jan Tytgat
- Toxicology and Pharmacology; University of Leuven; Belgium
| | - Eugene V. Grishin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
| | - Alexander A. Vassilevski
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry; Russian Academy of Sciences; Moscow Russia
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11
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Han T, Ming H, Deng L, Zhu H, Liu Z, Zhang J, Song Y. A novel expression vector for the improved solubility of recombinant scorpion venom in Escherichia coli. Biochem Biophys Res Commun 2017; 482:120-125. [DOI: 10.1016/j.bbrc.2016.09.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 09/11/2016] [Indexed: 12/30/2022]
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12
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Zhang S, Zhu L, Yu J, Xu J, Gao B, Zhou C, Zhu S. Evaluating the potential of a loop-extended scorpion toxin-like peptide as a protein scaffold. Protein Eng Des Sel 2016; 29:607-616. [PMID: 27672050 DOI: 10.1093/protein/gzw051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Revised: 08/06/2016] [Accepted: 08/26/2016] [Indexed: 11/14/2022] Open
Abstract
Grafting of exogenous bioactive sites or functional motifs onto structurally stable scaffolds to gain new functions represents an important research direction in protein engineering. Some engineered proteins have been developed into therapeutic drugs. MeuNaTxα-3 (abbreviated as MT-3) is a newly characterized scorpion sodium channel toxin-like peptide isolated from the venom of the scorpion Mesobuthus eupeus, which contains a rigid scaffold highly similar to classical scorpion sodium channel toxins and an extension of eight amino acids in its J-loop region. This extended loop constitutes a flexible region extruded from the scaffold and could be substituted by exogenous functional sequences. In this study, we experimentally evaluated the scaffold potential of MT-3 through grafting two small antimicrobial motifs to replace residues within the loop. Functional assays showed that the two engineered molecules exhibited elevated antimicrobial potency, as compared with the unmodified scaffold, without structural disruption, providing experimental evidence in favor of MT-3 as a promising scaffold in protein engineering.
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Affiliation(s)
- Shangfei Zhang
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China
| | - Limei Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China
| | - Jie Yu
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, 24 TongJiaXiang, 210009 Nanjing, Jiangsu, China
| | - Jun Xu
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, 24 TongJiaXiang, 210009 Nanjing, Jiangsu, China
| | - Bin Gao
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China
| | - Changlin Zhou
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, 24 TongJiaXiang, 210009 Nanjing, Jiangsu, China
| | - Shunyi Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China
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13
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Martin-Eauclaire MF, Salvatierra J, Bosmans F, Bougis PE. The scorpion toxin Bot IX is a potent member of the α-like family and has a unique N-terminal sequence extension. FEBS Lett 2016; 590:3221-32. [DOI: 10.1002/1873-3468.12357] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/05/2016] [Accepted: 08/05/2016] [Indexed: 11/08/2022]
Affiliation(s)
| | - Juan Salvatierra
- Department of Physiology; School of Medicine; Johns Hopkins University; Baltimore MD USA
| | - Frank Bosmans
- Department of Physiology; School of Medicine; Johns Hopkins University; Baltimore MD USA
- Solomon H. Snyder Department of Neuroscience; School of Medicine; Johns Hopkins University; Baltimore MD USA
| | - Pierre E. Bougis
- Aix Marseille Université; CNRS; CRN2M; UMR7286; PFRN-CAPM; Marseille France
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14
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Dang B, Kubota T, Mandal K, Correa AM, Bezanilla F, Kent SBH. Elucidation of the Covalent and Tertiary Structures of Biologically Active Ts3 Toxin. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201603420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Bobo Dang
- Department of Chemistry; University of Chicago; Chicago IL 60637 USA
- Department of Biochemistry & Molecular Biology; University of Chicago; Chicago IL 60637 USA
- Institute for Biophysical Dynamics; University of Chicago; Chicago IL 60637 USA
| | - Tomoya Kubota
- Department of Biochemistry & Molecular Biology; University of Chicago; Chicago IL 60637 USA
| | - Kalyaneswar Mandal
- Department of Chemistry; University of Chicago; Chicago IL 60637 USA
- Department of Biochemistry & Molecular Biology; University of Chicago; Chicago IL 60637 USA
- Institute for Biophysical Dynamics; University of Chicago; Chicago IL 60637 USA
| | - Ana M. Correa
- Department of Biochemistry & Molecular Biology; University of Chicago; Chicago IL 60637 USA
| | - Francisco Bezanilla
- Department of Biochemistry & Molecular Biology; University of Chicago; Chicago IL 60637 USA
- Institute for Biophysical Dynamics; University of Chicago; Chicago IL 60637 USA
| | - Stephen B. H. Kent
- Department of Chemistry; University of Chicago; Chicago IL 60637 USA
- Department of Biochemistry & Molecular Biology; University of Chicago; Chicago IL 60637 USA
- Institute for Biophysical Dynamics; University of Chicago; Chicago IL 60637 USA
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15
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Dang B, Kubota T, Mandal K, Correa AM, Bezanilla F, Kent SBH. Elucidation of the Covalent and Tertiary Structures of Biologically Active Ts3 Toxin. Angew Chem Int Ed Engl 2016; 55:8639-42. [PMID: 27244051 DOI: 10.1002/anie.201603420] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Indexed: 11/07/2022]
Abstract
Ts3 is an alpha scorpion toxin from the venom of the Brazilian scorpion Tityus serrulatus. Ts3 binds to the domain IV voltage sensor of voltage-gated sodium channels (Nav ) and slows down their fast inactivation. The covalent structure of the Ts3 toxin is uncertain, and the structure of the folded protein molecule is unknown. Herein, we report the total chemical synthesis of four candidate Ts3 toxin protein molecules and the results of structure-activity studies that enabled us to establish the covalent structure of biologically active Ts3 toxin. We also report the synthesis of the mirror image form of the Ts3 protein molecule, and the use of racemic protein crystallography to determine the folded (tertiary) structure of biologically active Ts3 toxin by X-ray diffraction.
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Affiliation(s)
- Bobo Dang
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, USA.,Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL, 60637, USA.,Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, 60637, USA
| | - Tomoya Kubota
- Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL, 60637, USA
| | - Kalyaneswar Mandal
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, USA.,Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL, 60637, USA.,Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, 60637, USA
| | - Ana M Correa
- Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL, 60637, USA
| | - Francisco Bezanilla
- Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL, 60637, USA.,Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, 60637, USA
| | - Stephen B H Kent
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, USA. .,Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL, 60637, USA. .,Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, 60637, USA.
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16
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Zhu L, Peigneur S, Gao B, Zhang S, Tytgat J, Zhu S. Target-Driven Positive Selection at Hot Spots of Scorpion Toxins Uncovers Their Potential in Design of Insecticides. Mol Biol Evol 2016; 33:1907-20. [PMID: 27189560 DOI: 10.1093/molbev/msw065] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Positive selection sites (PSSs), a class of amino acid sites with an excess of nonsynonymous to synonymous substitutions, are indicators of adaptive molecular evolution and have been detected in many protein families involved in a diversity of biological processes by statistical approaches. However, few studies are conducted to evaluate their functional significance and the driving force behind the evolution (i.e., agent of selection). Scorpion α-toxins are a class of multigene family of peptide neurotoxins affecting voltage-gated Na(+ )(Nav) channels, whose members exhibit differential potency and preference for insect and mammalian Nav channels. In this study, we undertook a systematical molecular dissection of nearly all the PSSs newly characterized in the Mesobuthus α-toxin family and a two-residue insertion ((19)AlaPhe(20)) located within a positively selected loop via mutational analysis of α-like MeuNaTxα-5, one member affecting both insect and mammalian Nav channels. This allows to identify hot-spot residues on its functional face involved in interaction with the receptor site of Nav channels, which comprises two PSSs (Ile(40) and Leu(41)) and the small insertion, both located on two spatially separated functional loops. Mutations at these hot-spots resulted in a remarkably decreased anti-mammalian activity in MeuNaTxα-5 with partially impaired or enhanced insecticide activity, suggesting the potential of PSSs in designing promising candidate insecticides from scorpion α-like toxins. Based on an experiment-guided toxin-channel complex model and high evolutionary variability in the receptor site of predators and prey of scorpions, we provide new evidence for target-driven adaptive evolution of scorpion toxins to deal with their targets' diversity.
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Affiliation(s)
- Limei 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
| | - Steve Peigneur
- Laboratory of Toxicology, University of Leuven, Leuven, Belgium
| | - 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
| | - Shangfei Zhang
- 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
| | - Jan Tytgat
- Laboratory of Toxicology, University of Leuven, Leuven, Belgium
| | - 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
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17
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Abstract
It is long known that peptide neurotoxins derived from a diversity of venomous animals evolve by positive selection following gene duplication, yet a force that drives their adaptive evolution remains a mystery. By using maximum-likelihood models of codon substitution, we analyzed molecular adaptation in scorpion sodium channel toxins from a specific species and found ten positively selected sites, six of which are located at the core-domain of scorpion α-toxins, a region known to interact with two adjacent loops in the voltage-sensor domain (DIV) of sodium channels, as validated by our newly constructed computational model of toxin-channel complex. Despite the lack of positive selection signals in these two loops, they accumulated extensive sequence variations by relaxed purifying selection in prey and predators of scorpions. The evolutionary variability in the toxin-bound regions of sodium channels indicates that accelerated substitutions in the multigene family of scorpion toxins is a consequence of dealing with the target diversity. This work presents an example of atypical co-evolution between animal toxins and their molecular targets, in which toxins suffered from more prominent selective pressure from the channels of their competitors. Our discovery helps explain the evolutionary rationality of gene duplication of toxins in a specific venomous species.
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18
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Jankowska M, Pawlowska-Mainville A, Stankiewicz M, Rogalska J, Wyszkowska J. Exposure to 50 Hz electromagnetic field changes the efficiency of the scorpion alpha toxin. J Venom Anim Toxins Incl Trop Dis 2015; 21:38. [PMID: 26430395 PMCID: PMC4589959 DOI: 10.1186/s40409-015-0040-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 09/24/2015] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Extremely low-frequency (50 Hz) electromagnetic field (ELF-EMF) is produced by electric power transmission lines and electronic devices of everyday use. Some phenomena are proposed as "first effects" of ELF-EMF: the discrete changes in the membrane potential and the increase of the calcium channel activity as well as the intracellular concentration of Ca(2+). Interaction of the scorpion alpha toxin with the sodium channel depends on the orientation of the charges and may be perturbed by changes in the membrane polarization. The toxin induces overexcitability in the nervous system and an increase in the neurotransmitters released with different consequences, mainly the paralysis of muscles. We assumed that the exposure to ELF-EMF 0.7 mT will change the effects of the insect selective scorpion alpha toxin (recombinant LqhαIT from Leiurus quinquestriatus hebraeus) at the level of the cercal nerve function, the synaptic transmission and on the level of entire insect organism. Taking into account the compensatory mechanisms in organisms, we tested in addition ten times higher ELF-EMF on whole insects. METHODS Experiments were performed in vivo on cockroaches (Periplaneta americana) and in vitro - on isolated cockroach abdominal nerve cord with cerci. In biotests, the effects of LqhαIT (10(-8) M) were estimated on the basis of the insect ability to turn back from dorsal to ventral side. Three groups were compared: the control one and the two exposed to ELF-EMF - 0.7 and 7 mT. Bioelectrical activity of the cercal nerve and of the connective nerve that leaves the terminal abdominal ganglion was recorded using extracellular electrodes. LqhαIT (5 × 10(-8) M) induced modifications of neuronal activity that were observed in the control cockroach preparations and in the ones exposed to ELF-EMF (0.7 mT). The exposure to ELF-EMF was carried out using coils with a size appropriate to the examined objects. RESULTS The exposure to ELF-EMF (0.7 mT) modified the effects of LqhαIT (5 × 10(-8) M) on activity of the cercal nerve and of the connective nerve. We observed a decrease of the toxin effect on the cercal nerve activity, but the toxic effect of LqhαIT on the connective nerve was increased. Biotests showed that toxicity of LqhαIT (10(-8) M) on cockroaches was reduced by the exposure to ELF-EMF (0.7 and 7 mT). CONCLUSIONS The exposure to 50 Hz ELF-EMF modified the mode of action of the anti-insect scorpion alpha toxin LqhαIT at cellular level of the cockroach nervous system and in biotests. Toxin appeared as a usefull tool in distinguishing between the primary and the secondary effects of ELF-EMF.
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Affiliation(s)
- Milena Jankowska
- />Nicolaus Copernicus University, Faculty of Biology and Environmental Protection, Torun, Poland
| | | | - Maria Stankiewicz
- />Nicolaus Copernicus University, Faculty of Biology and Environmental Protection, Torun, Poland
| | - Justyna Rogalska
- />Nicolaus Copernicus University, Faculty of Biology and Environmental Protection, Torun, Poland
| | - Joanna Wyszkowska
- />Nicolaus Copernicus University, Faculty of Biology and Environmental Protection, Torun, Poland
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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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Meng X, Xu Y, Zhao M, Wang F, Ma Y, Jin Y, Liu Y, Song Y, Zhang J. The Functional Property Changes of Muscular Nav1.4 and Cardiac Nav1.5 Induced by Scorpion Toxin BmK AGP-SYPU1 Mutants Y42F and Y5F. Biochemistry 2015; 54:2988-96. [DOI: 10.1021/acs.biochem.5b00067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Xiangxue Meng
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
- Benxi
Medicine Institute, Shenyang Pharmaceutical University, Shiqiaozi, 177005 Benxi, PR China
| | - Yijia Xu
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Mingyi Zhao
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Fangyang Wang
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Yuanyuan Ma
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Yao Jin
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Yanfeng Liu
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Yongbo Song
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
| | - Jinghai Zhang
- School of Life Sciences & Biopharmaceutical Science, Shenyang Pharmaceutical University, 103 Wenhua Road, 110016 Shenyang, PR China
- School
of Medical Devices, Shenyang Pharmaceutical University, 103 Wenhua
Road, 110016 Shenyang, PR China
- Benxi
Medicine Institute, Shenyang Pharmaceutical University, Shiqiaozi, 177005 Benxi, PR China
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21
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The specificity of Av3 sea anemone toxin for arthropods is determined at linker DI/SS2-S6 in the pore module of target sodium channels. Biochem J 2014; 463:271-7. [PMID: 25055135 DOI: 10.1042/bj20140576] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Av3 is a peptide neurotoxin from the sea anemone Anemonia viridis that shows specificity for arthropod voltage-gated sodium channels (Navs). Interestingly, Av3 competes with a scorpion α-toxin on binding to insect Navs and similarly inhibits the inactivation process, and thus has been classified as 'receptor site-3 toxin', although the two peptides are structurally unrelated. This raises questions as to commonalities and differences in the way both toxins interact with Navs. Recently, site-3 was partly resolved for scorpion α-toxins highlighting S1-S2 and S3-S4 external linkers at the DIV voltage-sensor module and the juxtaposed external linkers at the DI pore module. To uncover channel determinants involved in Av3 specificity for arthropods, the toxin was examined on channel chimaeras constructed with the external linkers of the mammalian brain Nav1.2a, which is insensitive to Av3, in the background of the Drosophila DmNav1. This approach highlighted the role of linker DI/SS2-S6, adjacent to the channel pore, in determining Av3 specificity. Point mutagenesis at DI/SS2-S6 accompanied by functional assays highlighted Trp404 and His405 as a putative point of Av3 interaction with DmNav1. His405 conservation in arthropod Navs compared with tyrosine in vertebrate Navs may represent an ancient substitution that explains the contemporary selectivity of Av3. Trp404 and His405 localization near the membrane surface and the hydrophobic bioactive surface of Av3 suggest that the toxin possibly binds at a cleft by DI/S6. A partial overlap in receptor site-3 of both toxins nearby DI/S6 may explain their binding competition capabilities.
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22
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Xu L, Li T, Liu H, Yang F, Liang S, Cao Z, Li W, Wu Y. Functional characterization of two novel scorpion sodium channel toxins from Lychas mucronatus. Toxicon 2014; 90:318-25. [DOI: 10.1016/j.toxicon.2014.08.075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 08/11/2014] [Accepted: 08/27/2014] [Indexed: 10/24/2022]
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23
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Aili SR, Touchard A, Escoubas P, Padula MP, Orivel J, Dejean A, Nicholson GM. Diversity of peptide toxins from stinging ant venoms. Toxicon 2014; 92:166-78. [PMID: 25448389 DOI: 10.1016/j.toxicon.2014.10.021] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 10/27/2014] [Indexed: 12/23/2022]
Abstract
Ants (Hymenoptera: Formicidae) represent a taxonomically diverse group of arthropods comprising nearly 13,000 extant species. Sixteen ant subfamilies have individuals that possess a stinger and use their venom for purposes such as a defence against predators, competitors and microbial pathogens, for predation, as well as for social communication. They exhibit a range of activities including antimicrobial, haemolytic, cytolytic, paralytic, insecticidal and pain-producing pharmacologies. While ant venoms are known to be rich in alkaloids and hydrocarbons, ant venoms rich in peptides are becoming more common, yet remain understudied. Recent advances in mass spectrometry techniques have begun to reveal the true complexity of ant venom peptide composition. In the few venoms explored thus far, most peptide toxins appear to occur as small polycationic linear toxins, with antibacterial properties and insecticidal activity. Unlike other venomous animals, a number of ant venoms also contain a range of homodimeric and heterodimeric peptides with one or two interchain disulfide bonds possessing pore-forming, allergenic and paralytic actions. However, ant venoms seem to have only a small number of monomeric disulfide-linked peptides. The present review details the structure and pharmacology of known ant venom peptide toxins and their potential as a source of novel bioinsecticides and therapeutic agents.
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Affiliation(s)
- Samira R Aili
- Neurotoxin Research Group, School of Medical & Molecular Biosciences, University of Technology Sydney, NSW 2007, Australia
| | - Axel Touchard
- CNRS, UMR Écologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France
| | - Pierre Escoubas
- VenomeTech, 473 Route des Dolines - Villa 3, 06560 Valbonne, France
| | - Matthew P Padula
- Neurotoxin Research Group, School of Medical & Molecular Biosciences, University of Technology Sydney, NSW 2007, Australia
| | - Jérôme Orivel
- CNRS, UMR Écologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France
| | - Alain Dejean
- CNRS, UMR Écologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France; Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, 118 Route de Narbonne, 31062 Toulouse, France.
| | - Graham M Nicholson
- Neurotoxin Research Group, School of Medical & Molecular Biosciences, University of Technology Sydney, NSW 2007, Australia.
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Chen R, Chung SH. Binding modes of two scorpion toxins to the voltage-gated potassium channel kv1.3 revealed from molecular dynamics. Toxins (Basel) 2014; 6:2149-61. [PMID: 25054783 PMCID: PMC4113748 DOI: 10.3390/toxins6072149] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/08/2014] [Accepted: 07/10/2014] [Indexed: 12/13/2022] Open
Abstract
Molecular dynamics (MD) simulations are used to examine the binding modes of two scorpion toxins, margatoxin (MgTx) and hongotoxin (HgTx), to the voltage gated K+ channel, Kv1.3. Using steered MD simulations, we insert either Lys28 or Lys35 of the toxins into the selectivity filter of the channel. The MgTx-Kv1.3 complex is stable when the side chain of Lys35 from the toxin occludes the channel filter, suggesting that Lys35 is the pore-blocking residue for Kv1.3. In this complex, Lys28 of the toxin forms one additional salt bridge with Asp449 just outside the filter of the channel. On the other hand, HgTx forms a stable complex with Kv1.3 when the side chain of Lys28 but not Lys35 protrudes into the filter of the channel. A survey of all the possible favorable binding modes of HgTx-Kv1.3 is carried out by rotating the toxin at 3° intervals around the channel axis while the position of HgTx-Lys28 relative to the filter is maintained. We identify two possible favorable binding modes: HgTx-Arg24 can interact with either Asp433 or Glu420 on the vestibular wall of the channel. The dissociation constants calculated from the two binding modes of HgTx-Kv1.3 differ by approximately 20 fold, suggesting that the two modes are of similar energetics.
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Affiliation(s)
- Rong Chen
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia.
| | - Shin-Ho Chung
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia.
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Characterization of a novel BmαTX47 toxin modulating sodium channels: the crucial role of expression vectors in toxin pharmacological activity. Toxins (Basel) 2014; 6:816-29. [PMID: 24577584 PMCID: PMC3968363 DOI: 10.3390/toxins6030816] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 12/30/2013] [Accepted: 01/20/2014] [Indexed: 12/19/2022] Open
Abstract
Long-chain scorpion toxins with four disulfide bridges exhibit various pharmacological features towards the different voltage-gated sodium channel subtypes. However, the toxin production still remains a huge challenge. Here, we reported the effects of different expression vectors on the pharmacological properties of a novel toxin BmαTX47 from the scorpion Buthus martensii Karsch. The recombinant BmαTX47 was obtained using the expression vector pET-14b and pET-28a, respectively. Pharmacological experiments showed that the recombinant BmαTX47 was a new α-scorpion toxin which could inhibit the fast inactivation of rNav1.2, mNav1.4 and hNav1.5 channels. Importantly, the different expression vectors were found to strongly affect BmαTX47 pharmacological activities while toxins were obtained by the same expression and purification procedures. When 10 µM recombinant BmαTX47 from the pET-28a vector was applied, the values of I5ms/Ipeak for rNav1.2, mNav1.4 and hNav1.5 channels were 44.12% ± 3.17%, 25.40% ± 4.89% and 65.34% ± 3.86%, respectively, which were better than those values of 11.33% ± 1.46%, 15.96% ± 1.87% and 5.24% ± 2.38% for rNav1.2, mNav1.4 and hNav1.5 channels delayed by 10 µM recombinant BmαTX47 from the pET-14b vector. The dose-response experiments further indicated the EC50 values of recombinant BmαTX47 from the pET-28a vector were 7262.9 ± 755.9 nM for rNav1.2 channel and 1005.8 ± 118.6 nM for hNav1.5 channel, respectively. Together, these findings highlighted the important role of expression vectors in scorpion toxin pharmacological properties, which would accelerate the understanding of the structure-function relationships of scorpion toxins and promote the potential application of toxins in the near future.
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26
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Smith JJ, Herzig V, King GF, Alewood PF. The insecticidal potential of venom peptides. Cell Mol Life Sci 2013; 70:3665-93. [PMID: 23525661 PMCID: PMC11114029 DOI: 10.1007/s00018-013-1315-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 12/19/2022]
Abstract
Pest insect species are a burden to humans as they destroy crops and serve as vectors for a wide range of diseases including malaria and dengue. Chemical insecticides are currently the dominant approach for combating these pests. However, the de-registration of key classes of chemical insecticides due to their perceived ecological and human health risks in combination with the development of insecticide resistance in many pest insect populations has created an urgent need for improved methods of insect pest control. The venoms of arthropod predators such as spiders and scorpions are a promising source of novel insecticidal peptides that often have different modes of action to extant chemical insecticides. These peptides have been optimized via a prey-predator arms race spanning hundreds of millions of years to target specific types of insect ion channels and receptors. Here we review the current literature on insecticidal venom peptides, with a particular focus on their structural and pharmacological diversity, and discuss their potential for deployment as insecticides.
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Affiliation(s)
- Jennifer J. Smith
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Volker Herzig
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Glenn F. King
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Paul F. Alewood
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072 Australia
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27
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Aphicidal efficacy of scorpion- and spider-derived neurotoxins. Toxicon 2013; 70:114-22. [DOI: 10.1016/j.toxicon.2013.04.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 04/10/2013] [Accepted: 04/17/2013] [Indexed: 01/14/2023]
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28
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Chugunov AO, Koromyslova AD, Berkut AA, Peigneur S, Tytgat J, Polyansky AA, Pentkovsky VM, Vassilevski AA, Grishin EV, Efremov RG. Modular organization of α-toxins from scorpion venom mirrors domain structure of their targets, sodium channels. J Biol Chem 2013; 288:19014-27. [PMID: 23637230 DOI: 10.1074/jbc.m112.431650] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
To gain success in the evolutionary "arms race," venomous animals such as scorpions produce diverse neurotoxins selected to hit targets in the nervous system of prey. Scorpion α-toxins affect insect and/or mammalian voltage-gated sodium channels (Na(v)s) and thereby modify the excitability of muscle and nerve cells. Although more than 100 α-toxins are known and a number of them have been studied into detail, the molecular mechanism of their interaction with Na(v)s is still poorly understood. Here, we employ extensive molecular dynamics simulations and spatial mapping of hydrophobic/hydrophilic properties distributed over the molecular surface of α-toxins. It is revealed that despite the small size and relatively rigid structure, these toxins possess modular organization from structural, functional, and evolutionary perspectives. The more conserved and rigid "core module" is supplemented with the "specificity module" (SM) that is comparatively flexible and variable and determines the taxon (mammal versus insect) specificity of α-toxin activity. We further show that SMs in mammal toxins are more flexible and hydrophilic than in insect toxins. Concomitant sequence-based analysis of the extracellular loops of Na(v)s suggests that α-toxins recognize the channels using both modules. We propose that the core module binds to the voltage-sensing domain IV, whereas the more versatile SM interacts with the pore domain in repeat I of Na(v)s. These findings corroborate and expand the hypothesis on different functional epitopes of toxins that has been reported previously. In effect, we propose that the modular structure in toxins evolved to match the domain architecture of Na(v)s.
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Affiliation(s)
- Anton O Chugunov
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia.
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Durek T, Vetter I, Wang CIA, Motin L, Knapp O, Adams DJ, Lewis RJ, Alewood PF. Chemical engineering and structural and pharmacological characterization of the α-scorpion toxin OD1. ACS Chem Biol 2013; 8:1215-22. [PMID: 23527544 DOI: 10.1021/cb400012k] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Scorpion α-toxins are invaluable pharmacological tools for studying voltage-gated sodium channels, but few structure-function studies have been undertaken due to their challenging synthesis. To address this deficiency, we report a chemical engineering strategy based upon native chemical ligation. The chemical synthesis of α-toxin OD1 was achieved by chemical ligation of three unprotected peptide segments. A high resolution X-ray structure (1.8 Å) of synthetic OD1 showed the typical βαββ α-toxin fold and revealed important conformational differences in the pharmacophore region when compared with other α-toxin structures. Pharmacological analysis of synthetic OD1 revealed potent α-toxin activity (inhibition of fast inactivation) at Nav1.7, as well as Nav1.4 and Nav1.6. In addition, OD1 also produced potent β-toxin activity at Nav1.4 and Nav1.6 (shift of channel activation in the hyperpolarizing direction), indicating that OD1 might interact at more than one site with Nav1.4 and Nav1.6. Investigation of nine OD1 mutants revealed that three residues in the reverse turn contributed significantly to selectivity, with the triple OD1 mutant (D9K, D10P, K11H) being 40-fold more selective for Nav1.7 over Nav1.6, while OD1 K11V was 5-fold more selective for Nav1.6 than Nav1.7. This switch in selectivity highlights the importance of the reverse turn for engineering α-toxins with altered selectivity at Nav subtypes.
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Affiliation(s)
- Thomas Durek
- Division of
Chemistry and Structural
Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
4072
| | - Irina Vetter
- Division of
Chemistry and Structural
Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
4072
| | - Ching-I Anderson Wang
- Division of
Chemistry and Structural
Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
4072
| | - Leonid Motin
- Health Innovations
Research
Institute, RMIT University, Victoria, Australia
3083
| | - Oliver Knapp
- Health Innovations
Research
Institute, RMIT University, Victoria, Australia
3083
| | - David J. Adams
- Health Innovations
Research
Institute, RMIT University, Victoria, Australia
3083
| | - Richard J. Lewis
- Division of
Chemistry and Structural
Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
4072
| | - Paul F. Alewood
- Division of
Chemistry and Structural
Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
4072
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The role of glycine residues at the C-terminal peptide segment in antinociceptive activity: a molecular dynamics simulation. J Mol Model 2012. [PMID: 23179767 DOI: 10.1007/s00894-012-1666-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Elucidating structural determinants in the functional regions of toxins can provide useful knowledge for designing novel analgesic peptides. Glycine residues at the C-terminal region of the neurotoxin BmK AGP-SYPU2 from the scorpion Buthus martensii Karsch (BmK) have been shown to be crucial to its analgesic activity. However, there has been no research on the structure-function relationship between the C-terminal segment of this toxin and its analgesic activity. To address this issue, we performed three MD simulations: one on the native structure and the other two on mutants of that structure. Results of these calculations suggest that the existence of glycine residues at the C-terminal segment stabilizes the protruding topology of the NC domain, which is considered an important determinant of the analgesic activity of BmK AGP-SYPU2.
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Wang X, Jimenez-Vargas JM, Xu C, Possani LD, Zhu S. Positive selection-guided mutational analysis revealing two key functional sites of scorpion ERG K(+) channel toxins. Biochem Biophys Res Commun 2012; 429:111-6. [PMID: 23103547 DOI: 10.1016/j.bbrc.2012.10.065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2012] [Accepted: 10/16/2012] [Indexed: 10/27/2022]
Abstract
Scorpion γ-KTx toxins are important molecular tools for studying physiological and pharmacological functions of human ether-á-go-go related gene (hERG) K(+) channels. To pinpoint functional residues of this class of toxins involved in channel binding, we employed a combined approach that integrates evolutionary information and site-directed mutagenesis. Among three positively selected sites (PSSs) identified here, two (Gln18 and Met35) were found to be associated with the toxin's function because their changes significantly decreased the potency of ErgTx1 (also called CnErg1) on hERG1 channel. On the contrary, no potency alteration was observed at the third PSS (Ala42) when the mutation was introduced, which could be due to its location far from the functional surface of the toxin. Our strategy will accelerate the research of structure-function relationship of scorpion K(+) channel toxins.
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Affiliation(s)
- Xueli Wang
- Group of Animal Innate Immunity, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
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Chen R, Chung SH. Binding Modes and Functional Surface of Anti-mammalian Scorpion α-Toxins to Sodium Channels. Biochemistry 2012; 51:7775-82. [DOI: 10.1021/bi300776g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Rong Chen
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Shin-Ho Chung
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
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Gurevitz M. Mapping of scorpion toxin receptor sites at voltage-gated sodium channels. Toxicon 2012; 60:502-11. [DOI: 10.1016/j.toxicon.2012.03.022] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 03/22/2012] [Accepted: 03/27/2012] [Indexed: 10/28/2022]
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Arginine Residues in the C-terminal and their Relationship with the Analgesic Activity of the Toxin from the Chinese Scorpion Buthus martensii Karsch (BmK AGP-SYPU1). Appl Biochem Biotechnol 2012; 168:247-55. [DOI: 10.1007/s12010-012-9768-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 06/04/2012] [Indexed: 10/28/2022]
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Nervous System of Periplaneta americana Cockroach as a Model in Toxinological Studies: A Short Historical and Actual View. J Toxicol 2012; 2012:143740. [PMID: 22666245 PMCID: PMC3361271 DOI: 10.1155/2012/143740] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 03/01/2012] [Indexed: 11/17/2022] Open
Abstract
Nervous system of Periplaneta americana cockroach is used in a wide range of pharmacological studies, including electrophysiological techniques. This paper presents its role as a preparation in the development of toxinological studies in the following electrophysiological methods: double-oil-gap technique on isolated giant axon, patch-clamp on DUM (dorsal unpaired median) neurons, microelectrode technique in situ conditions on axon in connective and DUM neurons in ganglion, and single-fiber oil-gap technique on last abdominal ganglion synapse. At the end the application of cockroach synaptosomal preparation is mentioned.
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Identification and phylogenetic analysis of Tityus pachyurus and Tityus obscurus novel putative Na+-channel scorpion toxins. PLoS One 2012; 7:e30478. [PMID: 22355312 PMCID: PMC3280238 DOI: 10.1371/journal.pone.0030478] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 12/16/2011] [Indexed: 11/19/2022] Open
Abstract
Background Colombia and Brazil are affected by severe cases of scorpionism. In Colombia the most dangerous accidents are caused by Tityus pachyurus that is widely distributed around this country. In the Brazilian Amazonian region scorpion stings are a common event caused by Tityus obscurus. The main objective of this work was to perform the molecular cloning of the putative Na+-channel scorpion toxins (NaScTxs) from T. pachyurus and T. obscurus venom glands and to analyze their phylogenetic relationship with other known NaScTxs from Tityus species. Methodology/Principal Findings cDNA libraries from venom glands of these two species were constructed and five nucleotide sequences from T. pachyurus were identified as putative modulators of Na+-channels, and were named Tpa4, Tpa5, Tpa6, Tpa7 and Tpa8; the latter being the first anti-insect excitatory β-class NaScTx in Tityus scorpion venom to be described. Fifteen sequences from T. obscurus were identified as putative NaScTxs, among which three had been previously described, and the others were named To4 to To15. The peptides Tpa4, Tpa5, Tpa6, To6, To7, To9, To10 and To14 are closely related to the α-class NaScTxs, whereas Tpa7, Tpa8, To4, To8, To12 and To15 sequences are more related to the β-class NaScTxs. To5 is possibly an arthropod specific toxin. To11 and To13 share sequence similarities with both α and β NaScTxs. By means of phylogenetic analysis using the Maximum Parsimony method and the known NaScTxs from Tityus species, these toxins were clustered into 14 distinct groups. Conclusions/Significance This communication describes new putative NaScTxs from T. pachyurus and T. obscurus and their phylogenetic analysis. The results indicate clear geographic separation between scorpions of Tityus genus inhabiting the Amazonian and Mountain Andes regions and those distributed over the Southern of the Amazonian rainforest. Based on the consensus sequences for the different clusters, a new nomenclature for the NaScTxs is proposed.
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Dai H, Yin S, Li T, Cao Z, Ji Y, Wu Y, Li W. Recombinant expression, purification, and characterization of scorpion toxin BmαTX14. Protein Expr Purif 2012; 82:325-31. [PMID: 22343065 DOI: 10.1016/j.pep.2012.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 02/01/2012] [Accepted: 02/02/2012] [Indexed: 12/19/2022]
Abstract
Long-chain and cysteine-rich scorpion toxins exhibit various pharmacological profiles for different voltage-gated sodium channel subtypes. However, the exploration of toxin structure-function relationships has progressed slowly due to the difficulty of obtaining synthetic or recombinant peptides. We now report that we have established an effective expression and purification approach for the novel scorpion toxin BmαTX14. BmαTX14 was over-expressed as inclusion bodies in Escherichia coli. The insoluble pellet was successfully transformed into active peptide by using a refolding procedure. One-step purification by reverse-phase HPLC was sufficient to generate chromatographically pure peptide. The yield of recombinant toxin reached 4mg from 1L LB medium. The pharmacological data further showed that BmαTX14 selectively inhibited the fast inactivation of mNa(v)1.4 (EC(50)=82.3±15.7nM) rather than that of rNa(v)1.2 (EC(50)>30μM), which indicates that BmαTX14 is a new α-like toxin. This work enables further structural, functional, and pharmacological studies of BmαTX14 and similar toxins.
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Affiliation(s)
- Hui Dai
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, PR China
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38
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Kozminsky-Atias A, Zilberberg N. Molding the business end of neurotoxins by diversifying evolution. FASEB J 2011; 26:576-86. [PMID: 22009937 DOI: 10.1096/fj.11-187179] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A diverse range of organisms utilize neurotoxins that target specific ion channels and modulate their activity. Typically, toxins are clustered into several multigene families, providing an organism with the upper hand in the never-ending predator-prey arms race. Several gene families, including those encoding certain neurotoxins, have been subject to diversifying selection forces, resulting in rapid gene evolution. Here we sought a spatial pattern in the distribution of both diversifying and purifying selection forces common to neurotoxin gene families. Utilizing the mechanistic empirical combination model, we analyzed various toxin families from different phyla affecting various receptors and relying on diverse modes of action. Through this approach, we were able to detect clear correlations between the pharmacological surface of a toxin and rapidly evolving domains, rich in positively selected residues. On the other hand, patches of negatively selected residues were restricted to the nontoxic face of the molecule and most likely help in stabilizing the tertiary structure of the toxin. We thus propose a mutual evolutionary strategy of venomous animals in which adaptive molecular evolution is directed toward the toxin active surface. Furthermore, we propose that the binding domains of unstudied toxins could be readily predicted using evolutionary considerations.
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Affiliation(s)
- Adi Kozminsky-Atias
- Department of Life Sciences, Ben Gurion University of the Negev, Beer-Sheva, Israel
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39
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Gur M, Kahn R, Karbat I, Regev N, Wang J, Catterall WA, Gordon D, Gurevitz M. Elucidation of the molecular basis of selective recognition uncovers the interaction site for the core domain of scorpion alpha-toxins on sodium channels. J Biol Chem 2011; 286:35209-17. [PMID: 21832067 PMCID: PMC3186375 DOI: 10.1074/jbc.m111.259507] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 08/05/2011] [Indexed: 12/19/2022] Open
Abstract
Neurotoxin receptor site-3 at voltage-gated Na(+) channels is recognized by various peptide toxin inhibitors of channel inactivation. Despite extensive studies of the effects of these toxins, their mode of interaction with the channel remained to be described at the molecular level. To identify channel constituents that interact with the toxins, we exploited the opposing preferences of LqhαIT and Lqh2 scorpion α-toxins for insect and mammalian brain Na(+) channels. Construction of the DIV/S1-S2, DIV/S3-S4, DI/S5-SS1, and DI/SS2-S6 external loops of the rat brain rNa(v)1.2a channel (highly sensitive to Lqh2) in the background of the Drosophila DmNa(v)1 channel (highly sensitive to LqhαIT), and examination of toxin activity on the channel chimera expressed in Xenopus oocytes revealed a substantial decrease in LqhαIT effect, whereas Lqh2 was as effective as at rNa(v)1.2a. Further substitutions of individual loops and specific residues followed by examination of gain or loss in Lqh2 and LqhαIT activities highlighted the importance of DI/S5-S6 (pore module) and the C-terminal region of DIV/S3 (gating module) of rNa(v)1.2a for Lqh2 action and selectivity. In contrast, a single substitution of Glu-1613 to Asp at DIV/S3-S4 converted rNa(v)1.2a to high sensitivity toward LqhαIT. Comparison of depolarization-driven dissociation of Lqh2 and mutant derivatives off their binding site at rNa(v)1.2a mutant channels has suggested that the toxin core domain interacts with the gating module of DIV. These results constitute the first step in better understanding of the way scorpion α-toxins interact with voltage-gated Na(+)-channels at the molecular level.
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Affiliation(s)
- Maya Gur
- Department of Plant Molecular Biology and Ecology, George S Wise Faculty of Life Sciences, Tel-Aviv University, Ramat-Aviv, Tel-Aviv 69978, Israel
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40
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Zhu S, Peigneur S, Gao B, Lu X, Cao C, Tytgat J. Evolutionary diversification of Mesobuthus α-scorpion toxins affecting sodium channels. Mol Cell Proteomics 2011; 11:M111.012054. [PMID: 21969612 DOI: 10.1074/mcp.m111.012054] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
α-Scorpion toxins constitute a family of peptide modulators that induce a prolongation of the action potential of excitable cells by inhibiting voltage-gated sodium channel inactivation. Although they all adopt a conserved structural scaffold, the potency and phylogentic preference of these toxins largely vary, which render them an intriguing model for studying evolutionary diversification among family members. Here, we report molecular characterization of a new multigene family of α-toxins comprising 13 members (named MeuNaTxα-1 to MeuNaTxα-13) from the scorpion Mesobuthus eupeus. Of them, five native toxins (MeuNaTxα-1 to -5) were purified to homogeneity from the venom and the solution structure of MeuNaTxα-5 was solved by nuclear magnetic resonance. A systematic functional evaluation of MeuNaTxα-1, -2, -4, and -5 was conducted by two-electrode voltage-clamp recordings on seven cloned mammalian voltage-gated sodium channels (Na(v)1.2 to Na(v)1.8) and the insect counterpart DmNa(v)1 expressed in Xenopus oocytes. Results show that all these four peptides slow inactivation of DmNa(v)1 and are inactive on Na(v)1.8 at micromolar concentrations. However, they exhibit differential specificity for the other six channel isoforms (Na(v)1.2 to Na(v)1.7), in which MeuNaTxα-4 shows no activity on these isoforms and thus represents the first Mesobuthus-derived insect-selective α-toxin identified so far with a half maximal effective concentration of 130 ± 2 nm on DmNa(v)1 and a half maximal lethal dose of about 200 pmol g(-1) on the insect Musca domestica; MeuNaTxα-2 only affects Na(v)1.4; MeuNaTxα-1 and MeuNaTxα-5 have a wider range of channel spectrum, the former active on Na(v)1.2, Na(v)1.3, Na(v)1.6, and Na(v)1.7, whereas the latter acting on Na(v)1.3-Na(v)1.7. Remarkably, MeuNaTxα-4 and MeuNaTxα-5 are two nearly identical peptides differing by only one point mutation at site 50 (A50V) but exhibit rather different channel subtype selectivity, highlighting a switch role of this site in altering the target specificity. By the maximum likelihood models of codon substitution, we detected nine positively selected sites (PSSs) that could be involved in functional diversification of Mesobuthus α-toxins. The PSSs include site 50 and other seven sites located in functional surfaces of α-toxins. This work represents the first thorough investigation of evolutionary diversification of α-toxins derived from a specific scorpion lineage from the perspectives of sequence, structure, function, and evolution.
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Affiliation(s)
- Shunyi Zhu
- Group of Animal Innate Immunity, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
| | - Steve Peigneur
- Laboratory of Toxicology, University of Leuven, O&N 2, Herestraat 49, P.O. Box 922, 3000 Leuven, Belgium
| | - Bin Gao
- Group of Animal Innate Immunity, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China
| | - Xiuxiu Lu
- State Key Laboratory of Bio-organic and Natural Product Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Chunyang Cao
- State Key Laboratory of Bio-organic and Natural Product Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Jan Tytgat
- Laboratory of Toxicology, University of Leuven, O&N 2, Herestraat 49, P.O. Box 922, 3000 Leuven, Belgium
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Wang Y, Hao Z, Shao J, Song Y, Li C, Li C, Zhao Y, Liu Y, Wei T, Wu C, Zhang J. The role of Ser54 in the antinociceptive activity of BmK9, a neurotoxin from the scorpion Buthus martensii Karsch. Toxicon 2011; 58:527-32. [PMID: 21906612 DOI: 10.1016/j.toxicon.2011.08.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Revised: 08/20/2011] [Accepted: 08/24/2011] [Indexed: 10/17/2022]
Abstract
Residue 54 has been shown to be important for bioactivity in several toxins. However, its role in the antinociceptive activity of toxins has not been evaluated yet. In this study, site-directed mutagenesis and mouse acetic acid writhing test were used to investigate the role of Ser54 in the antinociceptive activity of BmK9 neurotoxin from the Buthus martensii Karsch scorpion. Detailed mutagenesis analysis revealed that substitution of Ser54 by various polar amino acids produced no significant change in the antinociceptive activity, while all substitutions of nonpolar amino acid for Ser54 led to a significant loss of antinociceptive activity. Following the conformational analysis, it was suggested that Ser54 in BmK9 plays a functional role in the antinociceptive activity, the residue exerts its effect by means of a side-chain hydrogen bond.
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Affiliation(s)
- Yueqiu Wang
- School of Life Science and Bio-pharmaceutics, Shenyang Pharmaceutical University, PO Box 17, 103. Wenhua Road, Shenhe District, Shenyang, Liaoning Province 110016, PR China
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42
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Mapping the receptor site for alpha-scorpion toxins on a Na+ channel voltage sensor. Proc Natl Acad Sci U S A 2011; 108:15426-31. [PMID: 21876146 DOI: 10.1073/pnas.1112320108] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The α-scorpions toxins bind to the resting state of Na(+) channels and inhibit fast inactivation by interaction with a receptor site formed by domains I and IV. Mutants T1560A, F1610A, and E1613A in domain IV had lower affinities for Leiurus quinquestriatus hebraeus toxin II (LqhII), and mutant E1613R had ~73-fold lower affinity. Toxin dissociation was accelerated by depolarization and increased by these mutations, whereas association rates at negative membrane potentials were not changed. These results indicate that Thr1560 in the S1-S2 loop, Phe1610 in the S3 segment, and Glu1613 in the S3-S4 loop in domain IV participate in toxin binding. T393A in the SS2-S6 loop in domain I also had lower affinity for LqhII, indicating that this extracellular loop may form a secondary component of the receptor site. Analysis with the Rosetta-Membrane algorithm resulted in a model of LqhII binding to the voltage sensor in a resting state, in which amino acid residues in an extracellular cleft formed by the S1-S2 and S3-S4 loops in domain IV interact with two faces of the wedge-shaped LqhII molecule. The conserved gating charges in the S4 segment are in an inward position and form ion pairs with negatively charged amino acid residues in the S2 and S3 segments of the voltage sensor. This model defines the structure of the resting state of a voltage sensor of Na(+) channels and reveals its mode of interaction with a gating modifier toxin.
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Solution structure of a short-chain insecticidal toxin LaIT1 from the venom of scorpion Liocheles australasiae. Biochem Biophys Res Commun 2011; 411:738-44. [DOI: 10.1016/j.bbrc.2011.07.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2011] [Accepted: 07/06/2011] [Indexed: 01/22/2023]
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44
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Zhang R, Cui Y, Zhang X, Yang Z, Zhao Y, Song Y, Wu C, Zhang J. Soluble expression, purification and the role of C-terminal glycine residues in scorpion toxin BmK AGP-SYPU2. BMB Rep 2011; 43:801-6. [PMID: 21189156 DOI: 10.5483/bmbrep.2010.43.12.801] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The existence of glycine residues in long-chain scorpion toxins has been well documented. However, their role as analgesics has not been evaluated. To address this issue, we investigated the functional role of glycines in the C-terminal end of Chinese-scorpion toxin from Buthus martensii Karsch (BmK AGP-SYPU2) using site-directed mutagenesis and analgesic activity assays. Recombinant BmK AGP-SYPU2 and its mutants were efficiently expressed in E. coli and purified to homogeneity using immobilized metal ion affinity chromatography (IMAC) and cation exchange chromatography. The mouse-twisting test was used to detect the analgesic activity of BmK AGP-SYPU2 and its mutants. As a result, we identified glycines at the C-terminal end that, when altered, significantly affected analgesic activity. Also, Mut6566 was significantly decreased compared to BmK AGP-SYPU2. These data indicate that the glycines at the C-terminal end are important for the analgesic activity of BmK AGP-SYPU2.
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Affiliation(s)
- Rong Zhang
- School of Life Science and Bio-pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, P.R. China
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45
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Cui Y, Song YB, Ma L, Liu YF, Li GD, Wu CF, Zhang JH. Site-directed mutagenesis of the toxin from the Chinese scorpion Buthus martensii Karsch (BmKAS): insight into sites related to analgesic activity. Arch Pharm Res 2010; 33:1633-9. [PMID: 21052938 DOI: 10.1007/s12272-010-1012-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 03/26/2010] [Accepted: 05/13/2010] [Indexed: 11/24/2022]
Abstract
This study utilized the E. coli expression system to investigate the role of amino acid residues in toxin from the Chinese scorpion--Buthus martensii Karsch (BmKAS). To evaluate the extent to which residues of the toxin core contribute to its analgesic activity, ten mutants of BmKAS were obtained by PCR. Using site-directed mutagenesis, all of these residues were substituted with different amino acids. This study represents a thorough mapping and elucidation of the epitopes that form the molecular basis of the toxin's analgesic activity. Our results showed large mutant-dependent differences that emphasize the important roles of the studied residues.
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Affiliation(s)
- Yong Cui
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, China
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46
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Cui Y, Guo GL, Ma L, Hu N, Song YB, Liu YF, Wu CF, Zhang JH. Structure and function relationship of toxin from Chinese scorpion Buthus martensii Karsch (BmKAGAP): gaining insight into related sites of analgesic activity. Peptides 2010; 31:995-1000. [PMID: 20307602 DOI: 10.1016/j.peptides.2010.03.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 03/09/2010] [Accepted: 03/09/2010] [Indexed: 10/19/2022]
Abstract
In this study, an effective Escherichia coli expression system was used to study the role of residues in the antitumor-analgesic peptide from Chinese scorpion Buthus martensii Karsch (BmKAGAP). To evaluate the extent to which residues of the toxin core contribute to its analgesic activity, nine mutants of BmKAGAP were obtained by PCR. Using site-directed mutagenesis, all of these residues were individually substituted by one amino acid. These were then subjected to a circular dichroism analysis, and an analgesic activity assay in mice. This study represents a thorough mapping and elucidation of the epitopes that underlie the molecular basis of the analgesic activity. The three-dimensional structure of BmKAGAP was established by homology modeling. Our results revealed large mutant-dependent differences that indicated important roles for the studied residues. With our ongoing efforts for establishing the structure and analgesic activity relationship of BmKAGAP, we have succeeded in pinpointing which residues are important for the analgesic activity.
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Affiliation(s)
- Yong Cui
- School of Life Science and Bio-pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
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Location of the analgesic domain in Scorpion toxin BmK AGAP by mutagenesis of disulfide bridges. Biochem Biophys Res Commun 2010; 394:330-4. [PMID: 20206129 DOI: 10.1016/j.bbrc.2010.02.179] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2010] [Accepted: 02/26/2010] [Indexed: 11/22/2022]
Abstract
An increasing number of analgesic peptides have been found in the tail toxicyst, but there has been little research into their analgesic domains. Where are the analgesic domains in a conservative betaalphabetabeta topology conformation of the analgesic peptides? We have carried out research to address this question. On account of the importance of disulfide bonds in the study of protein structure, the conformational stability, catalytic activity and folding, and site-directed mutagenesis in disulfide bridges have been used to look for the analgesic domain in a mature antitumor-analgesic peptide from the venom of the Chinese scorpion Buthus martensii Karsch (BmK AGAP). The mouse-twisting assay was used to examine the analgesic activity of 12 mutants, in which two mutants (C22S, C46S) and (C16S, C36S), exhibited lower relative activity. Following the conformational analysis, one domain, called the "core domain", was found to be the key to the analgesic activity.
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Solution structure of BmKαTx11, a toxin from the venom of the Chinese scorpion Buthus martensii Karsch. Biochem Biophys Res Commun 2010; 391:627-33. [DOI: 10.1016/j.bbrc.2009.11.110] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 11/18/2009] [Indexed: 11/19/2022]
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Alvarenga L, Moreau V, Felicori L, Nguyen C, Duarte C, Chavez-Olortegui C, Molina F, Martin-Eauclaire MF, Granier C. Design of antibody-reactive peptides from discontinuous parts of scorpion toxins. Vaccine 2010; 28:970-80. [DOI: 10.1016/j.vaccine.2009.10.135] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 10/27/2009] [Accepted: 10/28/2009] [Indexed: 10/20/2022]
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Weinberger H, Moran Y, Gordon D, Turkov M, Kahn R, Gurevitz M. Positions under Positive Selection--Key for Selectivity and Potency of Scorpion -Toxins. Mol Biol Evol 2009; 27:1025-34. [DOI: 10.1093/molbev/msp310] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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