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Dyba B, Rudolphi-Szydło E, Kreczmer B, Barbasz A, Petrilla V, Petrillova M, Legáth J, Bocian A, Hus KK. Exploring the effects of three-finger toxins from Naja ashei venom on neuronal and immunological cancer cell membranes. Sci Rep 2024; 14:18570. [PMID: 39127758 DOI: 10.1038/s41598-024-69459-4] [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: 04/10/2024] [Accepted: 08/05/2024] [Indexed: 08/12/2024] Open
Abstract
Three-finger proteins are the most abundant toxins in the venom of Naja ashei, a snake species from the Elapidae family. This research aimed to describe the effects of varying charges of these proteins, isolated from Naja ashei venom using SEC and IEX chromatography. The study examined how differently charged three-finger toxin fractions interact with and affect neuroblastoma (SK-N-SH) and promyeloblast (HL-60) cells, as well as model Langmuir membranes and liposomes designed to mimic cellular lipid composition. Findings revealed that protein surface charges significantly impact cell survival (MTT assay), membrane damage (lactate dehydrogenase release, malondialdehyde formation), and the structural and electrochemical properties of model membranes (Langmuir membranes and zeta potential for liposomes and cancer cell lines). Results indicated that SK-N-SH cells, characterized by a higher negative charge on their cell membranes, interacted more effectively with positively charged toxins than HL-60 cells. However, the mechanism of these electrostatic interactions is complex. The research demonstrated that electrostatic and mechanical membrane modifications induced by venom proteins can significantly affect cell metabolism. Additionally, the total charge of the membrane, influenced by polar lipid components and phospholipid saturation, plays a decisive role in toxin interaction.
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Affiliation(s)
- Barbara Dyba
- Department of Biochemistry and Biophysics, University of the National Education Commission, Cracow, Poland.
| | - Elżbieta Rudolphi-Szydło
- Department of Biochemistry and Biophysics, University of the National Education Commission, Cracow, Poland
| | - Barbara Kreczmer
- Department of Biochemistry and Biophysics, University of the National Education Commission, Cracow, Poland
| | - Anna Barbasz
- Department of Biochemistry and Biophysics, University of the National Education Commission, Cracow, Poland
| | - Vladimír Petrilla
- Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy in Košice, Kosice, Slovakia
- Zoological Department, Zoological Garden Košice, Kosice, Slovakia
| | - Monika Petrillova
- Department of General Competencies, University of Veterinary Medicine and Pharmacy in Košice, Kosice, Slovakia
| | - Jaroslav Legáth
- Department of Biotechnology and Bioinformatics, University of Technology, Rzeszow, Poland
- Department of Pharmacology and Toxicology, University of Veterinary Medicine and Pharmacy, Kosice, Slovakia
| | - Aleksandra Bocian
- Department of Biotechnology and Bioinformatics, University of Technology, Rzeszow, Poland
| | - Konrad Kamil Hus
- Department of Biotechnology and Bioinformatics, University of Technology, Rzeszow, Poland
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2
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Roman-Ramos H, Prieto-da-Silva ÁRB, Dellê H, Floriano RS, Dias L, Hyslop S, Schezaro-Ramos R, Servent D, Mourier G, de Oliveira JL, Lemes DE, Costa-Lotufo LV, Oliveira JS, Menezes MC, Markus RP, Ho PL. The Cloning and Characterization of a Three-Finger Toxin Homolog (NXH8) from the Coralsnake Micrurus corallinus That Interacts with Skeletal Muscle Nicotinic Acetylcholine Receptors. Toxins (Basel) 2024; 16:164. [PMID: 38668589 PMCID: PMC11054780 DOI: 10.3390/toxins16040164] [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: 02/01/2024] [Revised: 03/04/2024] [Accepted: 03/20/2024] [Indexed: 04/29/2024] Open
Abstract
Coralsnakes (Micrurus spp.) are the only elapids found throughout the Americas. They are recognized for their highly neurotoxic venom, which is comprised of a wide variety of toxins, including the stable, low-mass toxins known as three-finger toxins (3FTx). Due to difficulties in venom extraction and availability, research on coralsnake venoms is still very limited when compared to that of other Elapidae snakes like cobras, kraits, and mambas. In this study, two previously described 3FTx from the venom of M. corallinus, NXH1 (3SOC1_MICCO), and NXH8 (3NO48_MICCO) were characterized. Using in silico, in vitro, and ex vivo experiments, the biological activities of these toxins were predicted and evaluated. The results showed that only NXH8 was capable of binding to skeletal muscle cells and modulating the activity of nAChRs in nerve-diaphragm preparations. These effects were antagonized by anti-rNXH8 or antielapidic sera. Sequence analysis revealed that the NXH1 toxin possesses eight cysteine residues and four disulfide bonds, while the NXH8 toxin has a primary structure similar to that of non-conventional 3FTx, with an additional disulfide bond on the first loop. These findings add more information related to the structural diversity present within the 3FTx class, while expanding our understanding of the mechanisms of the toxicity of this coralsnake venom and opening new perspectives for developing more effective therapeutic interventions.
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Affiliation(s)
- Henrique Roman-Ramos
- Laboratório de Biotecnologia, Programa de Pós-Graduação em Medicina, Universidade Nove de Julho (UNINOVE), São Paulo 01504-001, SP, Brazil; (H.D.); (J.L.d.O.); (D.E.L.)
| | | | - Humberto Dellê
- Laboratório de Biotecnologia, Programa de Pós-Graduação em Medicina, Universidade Nove de Julho (UNINOVE), São Paulo 01504-001, SP, Brazil; (H.D.); (J.L.d.O.); (D.E.L.)
| | - Rafael S. Floriano
- Laboratório de Toxinologia e Estudos Cardiovasculares, Universidade do Oeste Paulista (UNOESTE), Presidente Prudente 19067-175, SP, Brazil;
| | - Lourdes Dias
- Departamento de Farmacologia, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas 13083-887, SP, Brazil; (L.D.); (S.H.); (R.S.-R.)
| | - Stephen Hyslop
- Departamento de Farmacologia, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas 13083-887, SP, Brazil; (L.D.); (S.H.); (R.S.-R.)
| | - Raphael Schezaro-Ramos
- Departamento de Farmacologia, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas 13083-887, SP, Brazil; (L.D.); (S.H.); (R.S.-R.)
| | - Denis Servent
- Service d’Ingénierie Moléculaire pour la Santé (SIMoS), Département Médicaments et Technologies pour la Santé, Université Paris Saclay, Commissariat à l’énergie Atomique et aux Énergies Alternatives (CEA), F-91191 Gif sur Yvette, France; (D.S.); (G.M.)
| | - Gilles Mourier
- Service d’Ingénierie Moléculaire pour la Santé (SIMoS), Département Médicaments et Technologies pour la Santé, Université Paris Saclay, Commissariat à l’énergie Atomique et aux Énergies Alternatives (CEA), F-91191 Gif sur Yvette, France; (D.S.); (G.M.)
| | - Jéssica Lopes de Oliveira
- Laboratório de Biotecnologia, Programa de Pós-Graduação em Medicina, Universidade Nove de Julho (UNINOVE), São Paulo 01504-001, SP, Brazil; (H.D.); (J.L.d.O.); (D.E.L.)
| | - Douglas Edgard Lemes
- Laboratório de Biotecnologia, Programa de Pós-Graduação em Medicina, Universidade Nove de Julho (UNINOVE), São Paulo 01504-001, SP, Brazil; (H.D.); (J.L.d.O.); (D.E.L.)
| | - Letícia V. Costa-Lotufo
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo (USP), São Paulo 05508-000, SP, Brazil;
| | - Jane S. Oliveira
- Centro de Biotecnologia, Instituto Butantan, São Paulo 05503-900, SP, Brazil;
| | | | - Regina P. Markus
- Laboratório de Cronofarmacologia, Instituto de Biociências, Universidade de São Paulo (USP), São Paulo 05508-090, SP, Brazil;
| | - Paulo Lee Ho
- Centro Bioindustrial, Instituto Butantan, São Paulo 05503-900, SP, Brazil;
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3
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Bele T, Turk T, Križaj I. Nicotinic acetylcholine receptors in cancer: Limitations and prospects. Biochim Biophys Acta Mol Basis Dis 2024; 1870:166875. [PMID: 37673358 DOI: 10.1016/j.bbadis.2023.166875] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 08/09/2023] [Accepted: 08/31/2023] [Indexed: 09/08/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) have long been considered to solely mediate neurotransmission. However, their widespread distribution in the human body suggests a more diverse physiological role. Additionally, the expression of nAChRs is increased in certain cancers, such as lung cancer, and has been associated with cell proliferation, epithelial-to-mesenchymal cell transition, angiogenesis and apoptosis prevention. Several compounds that interact with these receptors have been identified as potential therapeutic agents. They have been tested as drugs for treating nicotine addiction, alcoholism, depression, pain and Alzheimer's disease. This review focuses on nAChR-mediated signalling in cancer, presenting opportunities for the development of innovative nAChR-based anticancer drugs. It displays the differences in expression of each nAChR subunit between normal and cancer cells for selected cancer types, highlighting their possible involvement in specific cases. Antagonists of nAChRs that could complement existing cancer therapies are summarised and critically discussed. We hope that this review will stimulate further research on the role of nAChRs in cancer potentially leading to innovative cancer therapies.
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Affiliation(s)
- T Bele
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Vrazov trg 2, SI-1000 Ljubljana, Slovenia.
| | - T Turk
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia.
| | - I Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
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4
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Palermo G, Schouten WM, Alonso LL, Ulens C, Kool J, Slagboom J. Acetylcholine-Binding Protein Affinity Profiling of Neurotoxins in Snake Venoms with Parallel Toxin Identification. Int J Mol Sci 2023; 24:16769. [PMID: 38069093 PMCID: PMC10706727 DOI: 10.3390/ijms242316769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 11/23/2023] [Accepted: 11/24/2023] [Indexed: 12/18/2023] Open
Abstract
Snakebite is considered a concerning issue and a neglected tropical disease. Three-finger toxins (3FTxs) in snake venoms primarily cause neurotoxic effects since they have high affinity for nicotinic acetylcholine receptors (nAChRs). Their small molecular size makes 3FTxs weakly immunogenic and therefore not appropriately targeted by current antivenoms. This study aims at presenting and applying an analytical method for investigating the therapeutic potential of the acetylcholine-binding protein (AChBP), an efficient nAChR mimic that can capture 3FTxs, for alternative treatment of elapid snakebites. In this analytical methodology, snake venom toxins were separated and characterised using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) and high-throughput venomics. By subsequent nanofractionation analytics, binding profiling of toxins to the AChBP was achieved with a post-column plate reader-based fluorescence-enhancement ligand displacement bioassay. The integrated method was established and applied to profiling venoms of six elapid snakes (Naja mossambica, Ophiophagus hannah, Dendroaspis polylepis, Naja kaouthia, Naja haje and Bungarus multicinctus). The methodology demonstrated that the AChBP is able to effectively bind long-chain 3FTxs with relatively high affinity, but has low or no binding affinity towards short-chain 3FTxs, and as such provides an efficient analytical platform to investigate binding affinity of 3FTxs to the AChBP and mutants thereof and to rapidly identify bound toxins.
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Affiliation(s)
- Giulia Palermo
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Wietse M. Schouten
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Luis Lago Alonso
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Chris Ulens
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, 3000 Leuven, Belgium;
| | - Jeroen Kool
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Julien Slagboom
- Centre for Analytical Sciences Amsterdam (CASA), 1012 WX Amsterdam, The Netherlands; (G.P.); (W.M.S.); (L.L.A.)
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Department of Chemistry and Pharmaceutical Sciences, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
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5
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Rathbun LA, Magliocco AM, Bamezai AK. Human LY6 gene family: potential tumor-associated antigens and biomarkers of prognosis in uterine corpus endometrial carcinoma. Oncotarget 2023; 14:426-437. [PMID: 37141412 PMCID: PMC10159366 DOI: 10.18632/oncotarget.28409] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
Abstract
The human Lymphocyte antigen-6 (LY6) gene family has recently gained interest for its possible role in tumor progression. We have carried out in silico analyses of all known LY6 gene expression and amplification in different cancers using TNMplot and cBioportal. We also have analyzed patient survival by Kaplan-Meier plotter after mining the TCGA database. We report that upregulated expression of many LY6 genes is associated with poor survival in uterine corpus endometrial carcinoma (UCEC) cancer patients. Importantly, the expression of several LY6 genes is elevated in UCEC when compared to the expression in normal uterine tissue. For example, LY6K expression is 8.25× higher in UCEC compared to normal uterine tissue, and this high expression is associated with poor survival with a hazard ratio of 2.42 (p-value = 0.0032). Therefore, some LY6 gene products may serve as tumor-associated antigens in UCEC, biomarkers for UCEC detection, and possibly targets for directing UCEC patient therapy. Further analysis of tumor-specific expression of LY6 gene family members and LY6-triggered signaling pathways is needed to uncover the function of LY6 proteins and their ability to endow tumor survival and poor prognosis in UCEC patients.
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Affiliation(s)
- Luke A Rathbun
- Department of Biology, Villanova University, Villanova, PA 19085, USA
| | | | - Anil K Bamezai
- Department of Biology, Villanova University, Villanova, PA 19085, USA
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6
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Zhou K, Luo W, Liu T, Ni Y, Qin Z. Neurotoxins Acting at Synaptic Sites: A Brief Review on Mechanisms and Clinical Applications. Toxins (Basel) 2022; 15:18. [PMID: 36668838 PMCID: PMC9865788 DOI: 10.3390/toxins15010018] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 12/29/2022] Open
Abstract
Neurotoxins generally inhibit or promote the release of neurotransmitters or bind to receptors that are located in the pre- or post-synaptic membranes, thereby affecting physiological functions of synapses and affecting biological processes. With more and more research on the toxins of various origins, many neurotoxins are now widely used in clinical treatment and have demonstrated good therapeutic outcomes. This review summarizes the structural properties and potential pharmacological effects of neurotoxins acting on different components of the synapse, as well as their important clinical applications, thus could be a useful reference for researchers and clinicians in the study of neurotoxins.
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Affiliation(s)
- Kunming Zhou
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases, College of Pharmaceutical Sciences, Suzhou Medical College of Soochow University, Suzhou 215123, China
| | - Weifeng Luo
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Tong Liu
- Institute of Pain Medicine and Special Environmental Medicine, Nantong University, Nantong 226019, China
| | - Yong Ni
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Zhenghong Qin
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases, College of Pharmaceutical Sciences, Suzhou Medical College of Soochow University, Suzhou 215123, China
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7
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Bamezai AK, Miwa JM. Editorial: Biology of Ly-6 Supergene Family in Health and Disease. Front Cell Dev Biol 2022; 10:949379. [PMID: 35813207 PMCID: PMC9260681 DOI: 10.3389/fcell.2022.949379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 06/06/2022] [Indexed: 11/13/2022] Open
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MT9, a natural peptide from black mamba venom antagonizes the muscarinic type 2 receptor and reverses the M2R-agonist-induced relaxation in rat and human arteries. Biomed Pharmacother 2022; 150:113094. [PMID: 35658242 DOI: 10.1016/j.biopha.2022.113094] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/25/2022] [Accepted: 05/04/2022] [Indexed: 11/20/2022] Open
Abstract
All five muscarinic receptors have important physiological roles. The endothelial M2 and M3 subtypes regulate arterial tone through direct coupling to Gq or Gi/o proteins. Yet, we lack selective pharmacological drugs to assess the respective contribution of muscarinic receptors to a given function. We used mamba snake venoms to identify a selective M2R ligand to investigate its contribution to arterial contractions. Using a bio-guided screening binding assay, we isolated MT9 from the black mamba venom, a three-finger toxin active on the M2R subtype. After sequencing and chemical synthesis of MT9, we characterized its structure by X-ray diffraction and determined its pharmacological characteristics by binding assays, functional tests, and ex vivo experiments on rat and human arteries. Although MT9 belongs to the three-finger fold toxins family, it is phylogenetically apart from the previously discovered muscarinic toxins, suggesting that two groups of peptides evolved independently and in a convergent way to target muscarinic receptors. The affinity of MT9 for the M2R is 100 times stronger than that for the four other muscarinic receptors. It also antagonizes the M2R/Gi pathways in cell-based assays. MT9 acts as a non-competitive antagonist against acetylcholine or arecaine, with low nM potency, for the activation of isolated rat mesenteric arteries. These results were confirmed on human internal mammary arteries. In conclusion, MT9 is the first fully characterized M2R-specific natural toxin. It should provide a tool for further understanding of the effect of M2R in various arteries and may position itself as a new drug candidate in cardio-vascular diseases.
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9
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Pruksaphon K, Yuvaniyama J, Ratanabanangkoon K. Immunogenicity of snake α-neurotoxins and the CD4 T cell epitopes. Toxicon 2022; 214:136-144. [DOI: 10.1016/j.toxicon.2022.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/22/2022] [Accepted: 05/17/2022] [Indexed: 11/26/2022]
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10
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Vanuopadath M, Raveendran D, Nair BG, Nair SS. Venomics and antivenomics of Indian spectacled cobra (Naja naja) from the Western Ghats. Acta Trop 2022; 228:106324. [PMID: 35093326 DOI: 10.1016/j.actatropica.2022.106324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 01/03/2023]
Abstract
Venom proteome profiling of Naja naja from the Western Ghats region in Kerala was achieved through SDS-PAGE and RP-HPLC followed by Q-TOF LC-MS/MS analysis, incorporating PEAKS and Novor assisted de novo sequencing methodologies. A total of 115 proteins distributed across 17 different enzymatic and non-enzymatic venom protein families were identified through conventional and 39 peptides through homology-driven proteomics approaches. Fourteen peptides derived through de novo complements the Mascot data indicating the importance of homology-driven approaches in improving protein sequence information. Among the protein families identified, glutathione peroxidase and endonuclease were reported for the first time in the Indian cobra venom. Immunological cross-reactivity assessed using Indian polyvalent antivenoms suggested that VINS showed better EC50 (2.48 µg/mL) value than that of PSAV (6.04 µg/mL) and Virchow (6.03 µg/mL) antivenoms. Western blotting experiments indicated that all the antivenoms elicited poor binding specificities, especially towards low molecular mass proteins. Second-generation antivenomics studies revealed that VINS antivenom was less efficient to detect many low molecular mass proteins such as three-finger toxins and Kunitz-type serine protease Inhibitors. Taken together, the present study enabled a large-scale characterization of the venom proteome of Naja naja from the Western Ghats and emphasized the need for developing more efficient antivenoms.
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Affiliation(s)
| | - Dileepkumar Raveendran
- Indriyam Biologics Pvt. Ltd., SCTIMST-TIMed, BMT Wing-Poojappura, Thiruvananthapuram 695 012, Kerala, India
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11
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Rivera AM, Swanson WJ. The Importance of Gene Duplication and Domain Repeat Expansion for the Function and Evolution of Fertilization Proteins. Front Cell Dev Biol 2022; 10:827454. [PMID: 35155436 PMCID: PMC8830517 DOI: 10.3389/fcell.2022.827454] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/12/2022] [Indexed: 11/13/2022] Open
Abstract
The process of gene duplication followed by gene loss or evolution of new functions has been studied extensively, yet the role gene duplication plays in the function and evolution of fertilization proteins is underappreciated. Gene duplication is observed in many fertilization protein families including Izumo, DCST, ZP, and the TFP superfamily. Molecules mediating fertilization are part of larger gene families expressed in a variety of tissues, but gene duplication followed by structural modifications has often facilitated their cooption into a fertilization function. Repeat expansions of functional domains within a gene also provide opportunities for the evolution of novel fertilization protein. ZP proteins with domain repeat expansions are linked to species-specificity in fertilization and TFP proteins that experienced domain duplications were coopted into a novel sperm function. This review outlines the importance of gene duplications and repeat domain expansions in the evolution of fertilization proteins.
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12
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Baudou FG, Rodriguez JP, Fusco L, de Roodt AR, De Marzi MC, Leiva L. South American snake venoms with abundant neurotoxic components. Composition and toxicological properties. A literature review. Acta Trop 2021; 224:106119. [PMID: 34481791 DOI: 10.1016/j.actatropica.2021.106119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 01/18/2023]
Abstract
In South America there are three snake genera with predominantly neurotoxic venoms: Crotalus, Micrurus and Hydrophis, which include nine species/subspecies, 97 species and a single marine species, respectively. Although accidents with neurotoxic venoms are less frequent than those with anticoagulant, cytotoxic or necrotic venoms (e.g. from Bothrops), they are of major public health importance. Venoms from genus Crotalus have been extensively studied, while data on the venoms from the other two genera are very limited, especially for Hydrophis. The venoms of North and South American Crotalus species show biochemical and physiopathological differences. The former species cause bothrops-like envenomation symptoms, while the latter mainly have neurotoxic and myotoxic effects, leading to respiratory paralysis and, occasionally, renal failure by myoglobinuria and death, often with no local lesions. Micrurus and Hydrophis also cause neurotoxic envenomations. Many studies have isolated, identified and characterized new enzymes and toxins, thus expanding the knowledge of snake venom composition. The present review summarizes the currently available information on neurotoxic venoms from South American snakes, with a focus on protein composition and toxicological properties. It also includes some comments concerning potential medical applications of elapid and crotalic toxins.
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Affiliation(s)
- Federico G Baudou
- Universidad Nacional de Luján (UNLu), Depto. de Ciencias Básicas, Luján, Buenos Aires, Argentina; Laboratorio de Inmunología, Instituto de Ecología y Desarrollo Sustentable (INEDES), UNLu-CONICET, Luján, Buenos Aires, Argentina.
| | - Juan P Rodriguez
- Laboratorio de Investigaciones Bioquímicas de la Facultad de Medicina (LIBIM), Instituto de Química Básica y Aplicada del Nordeste Argentino (IQUIBA-NEA), Universidad Nacional del Nordeste, Consejo Nacional de Investigaciones Científicas y Técnicas (UNNE-CONICET), Corrientes, Argentina
| | - Luciano Fusco
- Laboratorio de Investigación en Proteínas (LabInPro), IQUIBA-NEA (UNNE, CONICET), FaCENA, (UNNE), Corrientes, Argentina
| | - Adolfo R de Roodt
- Área Investigación y Desarrollo-Venenos, Instituto Nacional de Producción de Biológicos, Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán", Ministerio de Salud de la Nación, Argentina; Primera Cátedra de Toxicología, Facultad de Medicina, Universidad de Buenos Aires, Argentina; Laboratorio de Toxinopatología, Centro de Patología Experimental y Aplicada, Facultad de Medicina, Universidad de Buenos Aires, Argentina
| | - Mauricio C De Marzi
- Universidad Nacional de Luján (UNLu), Depto. de Ciencias Básicas, Luján, Buenos Aires, Argentina; Laboratorio de Inmunología, Instituto de Ecología y Desarrollo Sustentable (INEDES), UNLu-CONICET, Luján, Buenos Aires, Argentina
| | - Laura Leiva
- Laboratorio de Investigación en Proteínas (LabInPro), IQUIBA-NEA (UNNE, CONICET), FaCENA, (UNNE), Corrientes, Argentina
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Schulte LM, Martel A, Cruz-Elizalde R, Ramírez-Bautista A, Bossuyt F. Love bites: male frogs (Plectrohyla, Hylidae) use teeth scratching to deliver sodefrin precursor-like factors to females during amplexus. Front Zool 2021; 18:59. [PMID: 34823558 PMCID: PMC8613984 DOI: 10.1186/s12983-021-00445-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 11/09/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Efficient transfer of chemical signals is important for successful mating in many animal species. Multiple evolutionary lineages of animals evolved direct sex pheromone transmission during traumatic mating-the wounding of the partner with specialized devices-which helps to avoid signal loss to the environment. Although such direct transmission modes of so-called allohormone pheromones are well-documented in invertebrates, they are considered rare in vertebrates. Males of several species of the frog genus Plectrohyla (Hylidae, Anura) have elongated teeth and develop swollen lips during the breeding season. Here we investigated the possibility that these structures are used to scratch the females' skin and apply allohormone pheromones during traumatic mating in several Plectrohyla species. RESULTS Our behavioural observations revealed that males press their upper jaw onto the females' dorsum during amplexus, leaving small skin scratches with their teeth. Histological examinations of the males' lips identified specialized mucus glands, resembling known amphibian pheromone glands. Whole-transcriptome sequencing of these breeding glands showed high expression of sodefrin precursor-like factor (SPF) proteins, which are known to have a pheromone function in multiple amphibian species. CONCLUSIONS Our study suggests SPF delivery via traumatic mating in several anuran species: the males have specialized breeding glands in the lips for production and secretion and use their elongated teeth as wounding devices for application. We hypothesize that these SPF proteins end up in the females' circulatory system, where understanding their exact function will require further molecular, physiological and behavioural testing.
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Affiliation(s)
- Lisa M Schulte
- Department of Wildlife-/Zoo-Animal-Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438, Frankfurt/Main, Germany.
| | - An Martel
- Wildlife Health, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Raciel Cruz-Elizalde
- Laboratorio de Zoología, Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Avenida de Las Ciencias S/N, Santa Fe Juriquilla, C. P. 76230, Querétaro, Mexico
| | - Aurelio Ramírez-Bautista
- Laboratorio de Ecología de Poblaciones, Centro de Investigaciones Biológicas, Instituto de Ciencias Básicas E Ingeniería, Universidad Autónoma del Estado de Hidalgo, Km 4.5 carretera Pachuca-Tulancingo, 42184, Mineral de La Reforma, Hidalgo, Mexico
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Brussels, Belgium
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14
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Palasuberniam P, Tan KY, Tan CH. De novo venom gland transcriptomics of Calliophis bivirgata flaviceps: uncovering the complexity of toxins from the Malayan blue coral snake. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20210024. [PMID: 34616441 PMCID: PMC8476087 DOI: 10.1590/1678-9199-jvatitd-2021-0024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/12/2021] [Indexed: 03/03/2023] Open
Abstract
Background: The Malayan blue coral snake, Calliophis bivirgata
flaviceps, is a medically important venomous snake in Southeast
Asia. However, the complexity and diversity of its venom genes remain little
explored. Methods: To address this, we applied high-throughput next-generation sequencing to
profile the venom gland cDNA libraries of C. bivirgata
flaviceps. The transcriptome was de novo
assembled, followed by gene annotation, multiple sequence alignment and
analyses of the transcripts. Results: A total of 74 non-redundant toxin-encoding genes from 16 protein families
were identified, with 31 full-length toxin transcripts. Three-finger toxins
(3FTx), primarily delta-neurotoxins and cardiotoxin-like/cytotoxin-like
proteins, were the most diverse and abundantly expressed. The major 3FTx
(Cb_FTX01 and Cb_FTX02) are highly similar to calliotoxin, a
delta-neurotoxin previously reported in the venom of C.
bivirgata. This study also revealed a conserved tyrosine
residue at position 4 of the cardiotoxin-like/cytotoxin-like protein genes
in the species. These variants, proposed as Y-type CTX-like proteins, are
similar to the H-type CTX from cobras. The substitution is conservative
though, preserving a less toxic form of elapid CTX-like protein, as
indicated by the lack of venom cytotoxicity in previous laboratory and
clinical findings. The ecological role of these toxins, however, remains
unclear. The study also uncovered unique transcripts that belong to
phospholipase A2 of Groups IA and IB, and snake venom
metalloproteinases of PIII subclass, which show sequence variations from
those of Asiatic elapids. Conclusion: The venom gland transcriptome of C. bivirgata flaviceps from
Malaysia was de novo assembled and annotated. The diversity
and expression profile of toxin genes provide insights into the biological
and medical importance of the species.
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Affiliation(s)
- Praneetha Palasuberniam
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya. Kuala Lumpur, Malaysia.,Department of Biomedical Sciences, University Malaysia Sabah, Faculty of Medicine and Health Sciences, Kota Kinabalu, Sabah, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Laboratory, Department of Molecular Medicine, Faculty of Medicine, University of Malaya. Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Laboratory, Department of Pharmacology, Faculty of Medicine, University of Malaya. Kuala Lumpur, Malaysia
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15
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Beraldo E, Coelho GR, Sciani JM, Pimenta DC. Proteomic characterization of Naja mandalayensis venom. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20200125. [PMID: 34394208 PMCID: PMC8331017 DOI: 10.1590/1678-9199-jvatitd-2020-0125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 03/31/2021] [Indexed: 12/24/2022] Open
Abstract
Background Naja mandalayensis is a spitting cobra from Myanmar. To the
best of our knowledge, no studies on this venom composition have been
conducted so far. On the other hand, few envenomation descriptions state
that it elicits mainly local inflammation in the victims’ eyes, the
preferred target of this spiting cobra. Symptoms would typically include
burning and painful sensation, conjunctivitis, edema and temporary loss of
vision. Methods We have performed a liquid-chromatography (C18-RP-HPLC) mass spectrometry
(ESI-IT-TOF/MS) based approach in order to biochemically characterize
N. mandalayensis venom. Results A wide variety of three-finger toxins (cardiotoxins) and metallopeptidases
were detected. Less abundant, but still representative, were cysteine-rich
secretory proteins, L-amino-acid oxidases, phospholipases A2,
venom 5'-nucleotidase and a serine peptidase inhibitor. Other proteins were
present, but were detected in a relatively small concentration. Conclusion The present study set the basis for a better comprehension of the
envenomation from a molecular perspective and, by increasing the interest
and information available for this species, allows future venom comparisons
among cobras and their diverse venom proteins.
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Affiliation(s)
- Emídio Beraldo
- Laboratory of Biochemistry and Biophysics, Butantan Institute, São Paulo, SP, Brazil.,Graduation Program in Science - Toxinology, Butantan Institute, São Paulo, SP, Brazil
| | | | - Juliana Mozer Sciani
- Multidisciplinary Research Laboratory, São Francisco University, Bragança Paulista, SP, Brazil
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16
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Three-Finger Toxins from Brazilian Coral Snakes: From Molecular Framework to Insights in Biological Function. Toxins (Basel) 2021; 13:toxins13050328. [PMID: 33946590 PMCID: PMC8147190 DOI: 10.3390/toxins13050328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 04/22/2021] [Accepted: 04/28/2021] [Indexed: 12/19/2022] Open
Abstract
Studies on 3FTxs around the world are showing the amazing diversity in these proteins both in structure and function. In Brazil, we have not realized the broad variety of their amino acid sequences and probable diversified structures and targets. In this context, this work aims to conduct an in silico systematic study on available 3FTxs found in Micrurus species from Brazil. We elaborated a specific guideline for this toxin family. First, we grouped them according to their structural homologue predicted by HHPred server and further curated manually. For each group, we selected one sequence and constructed a representative structural model. By looking at conserved features and comparing with the information available in the literature for this toxin family, we managed to point to potential biological functions. In parallel, the phylogenetic relationship was estimated for our database by maximum likelihood analyses and a phylogenetic tree was constructed including the homologous 3FTx previously characterized. Our results highlighted an astonishing diversity inside this family of toxins, showing some groups with expected functional similarities to known 3FTxs, and pointing out others with potential novel roles and perhaps structures. Moreover, this classification guideline may be useful to aid future studies on these abundant toxins.
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17
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Tan CH, Tan KY. De Novo Venom-Gland Transcriptomics of Spine-Bellied Sea Snake ( Hydrophis curtus) from Penang, Malaysia-Next-Generation Sequencing, Functional Annotation and Toxinological Correlation. Toxins (Basel) 2021; 13:toxins13020127. [PMID: 33572266 PMCID: PMC7915529 DOI: 10.3390/toxins13020127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/31/2021] [Accepted: 02/02/2021] [Indexed: 01/26/2023] Open
Abstract
Envenomation resulted from sea snake bite is a highly lethal health hazard in Southeast Asia. Although commonly caused by sea snakes of Hydrophiinae, each species is evolutionarily distinct and thus, unveiling the toxin gene diversity within individual species is important. Applying next-generation sequencing, this study investigated the venom-gland transcriptome of Hydrophis curtus (spine-bellied sea snake) from Penang, West Malaysia. The transcriptome was de novo assembled, followed by gene annotation and sequence analyses. Transcripts with toxin annotation were only 96 in number but highly expressed, constituting 48.18% of total FPKM in the overall transcriptome. Of the 21 toxin families, three-finger toxins (3FTX) were the most abundantly expressed and functionally diverse, followed by phospholipases A2. Lh_FTX001 (short neurotoxin) and Lh_FTX013 (long neurotoxin) were the most dominant 3FTXs expressed, consistent with the pathophysiology of envenomation. Lh_FTX001 and Lh_FTX013 were variable in amino acid compositions and predicted epitopes, while Lh_FTX001 showed high sequence similarity with the short neurotoxin from Hydrophis schistosus, supporting cross-neutralization effect of Sea Snake Antivenom. Other toxins of low gene expression, for example, snake venom metalloproteinases and L-amino acid oxidases not commonly studied in sea snake venom were also identified, enriching the knowledgebase of sea snake toxins for future study.
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Affiliation(s)
- Choo Hock Tan
- Venom Research and Toxicoogy Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
- Correspondence:
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
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18
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Gutiérrez JM, Vargas M, Segura Á, Herrera M, Villalta M, Solano G, Sánchez A, Herrera C, León G. In Vitro Tests for Assessing the Neutralizing Ability of Snake Antivenoms: Toward the 3Rs Principles. Front Immunol 2021; 11:617429. [PMID: 33505403 PMCID: PMC7829219 DOI: 10.3389/fimmu.2020.617429] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 11/23/2020] [Indexed: 12/24/2022] Open
Abstract
There is an urgent need to strengthen the implementation of the 3Rs principle (Replacement, Reduction and Refinement) in the use of experimental animals in toxinological research and in the assessment of the neutralizing efficacy of snake antivenoms. This is a challenging task owing to the inherent complexity of snake venoms. The state of the art on this topic is hereby reviewed, with emphasis on the studies in which a correlation has been observed between in vivo toxicity tests and in vitro surrogate assays, particularly in the study of lethal activity of venoms and its neutralization. Correlations have been described with some venoms-antivenoms when using: (a) enzyme immunoassays, (b) hemagglutination, (c) enzyme assays (proteinase, phospholipase A2), (d) in vitro coagulant effect on plasma, (e) cell culture assays for cytotoxicity, (f) functional assays for assessing neurotoxicity in vitro, (g) use of hens' eggs, and (h) antivenomics. Additionally, the routine introduction of analgesia in these assays and the design of more 'humane' protocols for the lethality test are being pursued. It is expected that the next years will witness a growing awareness of the relevance of the 3Rs principles in antivenom testing, and that new in vitro alternatives and more 'humane' experimental designs will emerge in this field.
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Affiliation(s)
| | - Mariángela Vargas
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Álvaro Segura
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - María Herrera
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Mauren Villalta
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Gabriela Solano
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Andrés Sánchez
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
| | - Cristina Herrera
- Facultad de Farmacia, Universidad de Costa Rica, San José, Costa Rica
| | - Guillermo León
- Instituto Clodomiro Picado, Facultad de Microbiología, San José, Costa Rica
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19
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Kowalczyk P, Madej A, Szymczak M, Ostaszewski R. α-Amidoamids as New Replacements of Antibiotics-Research on the Chosen K12, R2-R4 E. coli Strains. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E5169. [PMID: 33207799 PMCID: PMC7697494 DOI: 10.3390/ma13225169] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/03/2020] [Accepted: 11/12/2020] [Indexed: 01/04/2023]
Abstract
A preliminary study of α-amidoamids as new potential antimicrobial drugs was performed. Special emphasis was placed on selection of structure of α-amidoamids with the highest biological activity against different types of Gram-stained bacteria by lipopolysaccharide (LPS). Herein, Escherichia coli model strains K12 (without LPS in its structure) and R1-R4 (with different length LPS in its structure) were used. The presented work showed that the antibacterial activity of α-amidoamids depends on their structure and affects the LPS of bacteria. Moreover, the influence of various newly synthesized α-amidoamids on bacteria possessing smooth and rought LPS and oxidative damage of plasmid DNA caused by all newly obtained compounds was indicated. The presented studies clearly explain that α-amidoamids can be used as substitutes for antibiotics. The chemical and biological activity of the analysed α-amidoamids was associated with short alkyl chain and different isocyanides molecules in their structure such as: tetr-butyl isocyanide or 2,5-dimethoxybenzyl isocyanide. The observed results are especially important in the case of the increasing resistance of bacteria to various drugs and antibiotics.
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Affiliation(s)
- Paweł Kowalczyk
- Department of Animal Nutrition, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110 Jabłonna, Poland
| | - Arleta Madej
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland;
| | - Mateusz Szymczak
- Department of Molecular Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland;
| | - Ryszard Ostaszewski
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland;
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20
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Pruksaphon K, Tan KY, Tan CH, Simsiriwong P, Gutiérrez JM, Ratanabanangkoon K. An in vitro α-neurotoxin-nAChR binding assay correlates with lethality and in vivo neutralization of a large number of elapid neurotoxic snake venoms from four continents. PLoS Negl Trop Dis 2020; 14:e0008581. [PMID: 32857757 PMCID: PMC7535858 DOI: 10.1371/journal.pntd.0008581] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/05/2020] [Accepted: 07/09/2020] [Indexed: 11/25/2022] Open
Abstract
The aim of this study was to develop an in vitro assay for use in place of in vivo assays of snake venom lethality and antivenom neutralizing potency. A novel in vitro assay has been developed based on the binding of post-synaptically acting α-neurotoxins to nicotinic acetylcholine receptor (nAChR), and the ability of antivenoms to prevent this binding. The assay gave high correlation in previous studies with the in vivo murine lethality tests (Median Lethal Dose, LD50), and the neutralization of lethality assays (Median Effective Dose, ED50) by antisera against Naja kaouthia, Naja naja and Bungarus candidus venoms. Here we show that, for the neurotoxic venoms of 20 elapid snake species from eight genera and four continents, the in vitro median inhibitory concentrations (IC50s) for α-neurotoxin binding to purified nAChR correlated well with the in vivo LD50s of the venoms (R2 = 0.8526, p < 0.001). Furthermore, using this assay, the in vitro ED50s of a horse pan-specific antiserum against these venoms correlated significantly with the corresponding in vivo murine ED50s, with R2 = 0.6896 (p < 0.01). In the case of four elapid venoms devoid or having a very low concentration of α-neurotoxins, no inhibition of nAChR binding was observed. Within the philosophy of 3Rs (Replacement, Reduction and Refinement) in animal testing, the in vitro α-neurotoxin-nAChR binding assay can effectively substitute the mouse lethality test for toxicity and antivenom potency evaluation for neurotoxic venoms in which α-neurotoxins predominate. This will greatly reduce the number of mice used in toxicological research and antivenom production laboratories. The simpler, faster, cheaper and less variable in vitro assay should also expedite the development of pan-specific antivenoms against various medically important snakes in many parts of the world.
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Affiliation(s)
- Kritsada Pruksaphon
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kae Yi Tan
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - José María Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
| | - Kavi Ratanabanangkoon
- Laboratory of Immunology, Chulabhorn Research Institute, Bangkok, Thailand
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
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21
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Bhopatkar AA, Uversky VN, Rangachari V. Disorder and cysteines in proteins: A design for orchestration of conformational see-saw and modulatory functions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 174:331-373. [PMID: 32828470 DOI: 10.1016/bs.pmbts.2020.06.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Being responsible for more than 90% of cellular functions, protein molecules are workhorses in all the life forms. In order to cater for such a high demand, proteins have evolved to adopt diverse structures that allow them to perform myriad of functions. Beginning with the genetically directed amino acid sequence, the classical understanding of protein function involves adoption of hierarchically complex yet ordered structures. However, advances made over the last two decades have revealed that inasmuch as 50% of eukaryotic proteome exists as partially or fully disordered structures. Significance of such intrinsically disordered proteins (IDPs) is further realized from their ability to exhibit multifunctionality, a feature attributable to their conformational plasticity. Among the coded amino acids, cysteines are considered to be "order-promoting" due to their ability to form inter- or intramolecular disulfide bonds, which confer robust thermal stability to the protein structure in oxidizing conditions. The co-existence of order-promoting cysteines with disorder-promoting sequences seems counter-intuitive yet many proteins have evolved to contain such sequences. In this chapter, we review some of the known cysteine-containing protein domains categorized based on the number of cysteines they possess. We show that many protein domains contain disordered sequences interspersed with cysteines. We show that a positive correlation exists between the degree of cysteines and disorder within the sequences that flank them. Furthermore, based on the computational platform, IUPred2A, we show that cysteine-rich sequences display significant disorder in the reduced but not the oxidized form, increasing the potential for such sequences to function in a redox-sensitive manner. Overall, this chapter provides insights into an exquisite evolutionary design wherein disordered sequences with interspersed cysteines enable potential modulatory protein functions under stress and environmental conditions, which thus far remained largely inconspicuous.
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Affiliation(s)
- Anukool A Bhopatkar
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Vladimir N Uversky
- Department of Molecular Medicine and Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, Russia
| | - Vijayaraghavan Rangachari
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, MS, United States; Center of Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, MS, United States.
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22
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Rahman MM, Teng J, Worrell BT, Noviello CM, Lee M, Karlin A, Stowell MHB, Hibbs RE. Structure of the Native Muscle-type Nicotinic Receptor and Inhibition by Snake Venom Toxins. Neuron 2020; 106:952-962.e5. [PMID: 32275860 DOI: 10.1016/j.neuron.2020.03.012] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/13/2020] [Accepted: 03/15/2020] [Indexed: 12/28/2022]
Abstract
The nicotinic acetylcholine receptor, a pentameric ligand-gated ion channel, converts the free energy of binding of the neurotransmitter acetylcholine into opening of its central pore. Here we present the first high-resolution structure of the receptor type found in muscle-endplate membrane and in the muscle-derived electric tissues of fish. The native receptor was purified from Torpedo electric tissue and functionally reconstituted in lipids optimal for cryo-electron microscopy. The receptor was stabilized in a closed state by the binding of α-bungarotoxin. The structure reveals the binding of a toxin molecule at each of two subunit interfaces in a manner that would block the binding of acetylcholine. It also reveals a closed gate in the ion-conducting pore, formed by hydrophobic amino acid side chains, located ∼60 Å from the toxin binding sites. The structure provides a framework for understanding gating in ligand-gated channels and how mutations in the acetylcholine receptor cause congenital myasthenic syndromes.
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Affiliation(s)
- Md Mahfuzur Rahman
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jinfeng Teng
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Brady T Worrell
- Department of Molecular, Cellular & Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Colleen M Noviello
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Myeongseon Lee
- Department of Molecular, Cellular & Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Arthur Karlin
- Center for Molecular Recognition & Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Michael H B Stowell
- Department of Molecular, Cellular & Developmental Biology, University of Colorado, Boulder, CO 80309, USA.
| | - Ryan E Hibbs
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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23
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Suryamohan K, Krishnankutty SP, Guillory J, Jevit M, Schröder MS, Wu M, Kuriakose B, Mathew OK, Perumal RC, Koludarov I, Goldstein LD, Senger K, Dixon MD, Velayutham D, Vargas D, Chaudhuri S, Muraleedharan M, Goel R, Chen YJJ, Ratan A, Liu P, Faherty B, de la Rosa G, Shibata H, Baca M, Sagolla M, Ziai J, Wright GA, Vucic D, Mohan S, Antony A, Stinson J, Kirkpatrick DS, Hannoush RN, Durinck S, Modrusan Z, Stawiski EW, Wiley K, Raudsepp T, Kini RM, Zachariah A, Seshagiri S. The Indian cobra reference genome and transcriptome enables comprehensive identification of venom toxins. Nat Genet 2020; 52:106-117. [PMID: 31907489 PMCID: PMC8075977 DOI: 10.1038/s41588-019-0559-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/22/2019] [Indexed: 12/30/2022]
Abstract
Snakebite envenoming is a serious and neglected tropical disease that kills ~100,000 people annually. High-quality, genome-enabled comprehensive characterization of toxin genes will facilitate development of effective humanized recombinant antivenom. We report a de novo near-chromosomal genome assembly of Naja naja, the Indian cobra, a highly venomous, medically important snake. Our assembly has a scaffold N50 of 223.35 Mb, with 19 scaffolds containing 95% of the genome. Of the 23,248 predicted protein-coding genes, 12,346 venom-gland-expressed genes constitute the ‘venom-ome’ and this included 139 genes from 33 toxin families. Among the 139 toxin genes were 19 ‘venom-ome-specific toxins’ (VSTs) that showed venom-gland-specific expression, and these probably encode the minimal core venom effector proteins. Synthetic venom reconstituted through recombinant VST expression will aid in the rapid development of safe and effective synthetic antivenom. Additionally, our genome could serve as a reference for snake genomes, support evolutionary studies and enable venom-driven drug discovery. Analysis of a near-chromosomal genome assembly and transcriptome profiling of the Indian cobra identifies genes expressed in the venom glands. These data should help develop a new antivenom.
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Affiliation(s)
- Kushal Suryamohan
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA.,MedGenome Inc., Foster City, CA, USA
| | - Sajesh P Krishnankutty
- AgriGenome Labs Private Ltd, Kochi, India.,SciGenom Research Foundation, Bangalore, India
| | - Joseph Guillory
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | - Matthew Jevit
- Molecular Cytogenetics laboratory, Texas A&M University, College Station, TX, USA
| | - Markus S Schröder
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | - Meng Wu
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | | | | | | | - Ivan Koludarov
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology, Onna-son, Japan
| | - Leonard D Goldstein
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA.,Department of Bioinformatics and Computational Biology, Genentech, Inc., South San Francisco, CA, USA
| | - Kate Senger
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | | | | | - Derek Vargas
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA.,MedGenome Inc., Foster City, CA, USA
| | - Subhra Chaudhuri
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | | | - Ridhi Goel
- AgriGenome Labs Private Ltd, Kochi, India
| | - Ying-Jiun J Chen
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | - Aakrosh Ratan
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Peter Liu
- Department of Microchemistry Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, CA, USA
| | - Brendan Faherty
- Department of Microchemistry Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, CA, USA
| | - Guillermo de la Rosa
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Hiroki Shibata
- Division of Genomics, Medical Institute of Bioregulation, Kyushu University, Fukuouka, Japan
| | - Miriam Baca
- Department of Pathology, Genentech, Inc., South San Francisco, CA, USA
| | - Meredith Sagolla
- Department of Pathology, Genentech, Inc., South San Francisco, CA, USA
| | - James Ziai
- Department of Pathology, Genentech, Inc., South San Francisco, CA, USA
| | - Gus A Wright
- College of Veterinary Medicine, Flow Cytometry Shared Resource Laboratory, Texas A&M University, College Station, TX, USA
| | - Domagoj Vucic
- Department of Early Discovery Biochemistry, Genentech, Inc., South San Francisco, CA, USA
| | - Sangeetha Mohan
- Department of Molecular Biology, SciGenom Labs, Kochi, India
| | - Aju Antony
- Department of Molecular Biology, SciGenom Labs, Kochi, India
| | - Jeremy Stinson
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | - Donald S Kirkpatrick
- Department of Microchemistry Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, CA, USA
| | - Rami N Hannoush
- Department of Early Discovery Biochemistry, Genentech, Inc., South San Francisco, CA, USA
| | - Steffen Durinck
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA.,Department of Bioinformatics and Computational Biology, Genentech, Inc., South San Francisco, CA, USA
| | - Zora Modrusan
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA
| | - Eric W Stawiski
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA.,MedGenome Inc., Foster City, CA, USA
| | | | - Terje Raudsepp
- Molecular Cytogenetics laboratory, Texas A&M University, College Station, TX, USA
| | - R Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Arun Zachariah
- SciGenom Research Foundation, Bangalore, India.,Wayanad Wildlife Sanctuary, Sultan Bathery, India
| | - Somasekar Seshagiri
- Molecular Biology Department, Genentech, Inc., South San Francisco, CA, USA. .,SciGenom Research Foundation, Bangalore, India.
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Rey-Suárez P, Saldarriaga-Córdoba M, Torres U, Marin-Villa M, Lomonte B, Núñez V. Novel three-finger toxins from Micrurus dumerilii and Micrurus mipartitus coral snake venoms: Phylogenetic relationships and characterization of Clarkitoxin-I-Mdum. Toxicon 2019; 170:85-93. [DOI: 10.1016/j.toxicon.2019.09.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 11/11/2022]
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Modahl CM, Brahma RK, Koh CY, Shioi N, Kini RM. Omics Technologies for Profiling Toxin Diversity and Evolution in Snake Venom: Impacts on the Discovery of Therapeutic and Diagnostic Agents. Annu Rev Anim Biosci 2019; 8:91-116. [PMID: 31702940 DOI: 10.1146/annurev-animal-021419-083626] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Snake venoms are primarily composed of proteins and peptides, and these toxins have developed high selectivity to their biological targets. This makes venoms interesting for exploration into protein evolution and structure-function relationships. A single venom protein superfamily can exhibit a variety of pharmacological effects; these variations in activity originate from differences in functional sites, domains, posttranslational modifications, and the formations of toxin complexes. In this review, we discuss examples of how the major venom protein superfamilies have diversified, as well as how newer technologies in the omics fields, such as genomics, transcriptomics, and proteomics, can be used to characterize both known and unknown toxins.Because toxins are bioactive molecules with a rich diversity of activities, they can be useful as therapeutic and diagnostic agents, and successful examples of toxin applications in these areas are also reviewed. With the current rapid pace of technology, snake venom research and its applications will only continue to expand.
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Affiliation(s)
- Cassandra M Modahl
- Protein Science Lab, Department of Biological Sciences, University of Singapore, Singapore 119077; , ,
| | - Rajeev Kungur Brahma
- Protein Science Lab, Department of Biological Sciences, University of Singapore, Singapore 119077; , ,
| | - Cho Yeow Koh
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077;
| | - Narumi Shioi
- Protein Science Lab, Department of Biological Sciences, University of Singapore, Singapore 119077; , , .,Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan;
| | - R Manjunatha Kini
- Protein Science Lab, Department of Biological Sciences, University of Singapore, Singapore 119077; , ,
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Snake Venoms in Drug Discovery: Valuable Therapeutic Tools for Life Saving. Toxins (Basel) 2019; 11:toxins11100564. [PMID: 31557973 PMCID: PMC6832721 DOI: 10.3390/toxins11100564] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/20/2019] [Accepted: 09/22/2019] [Indexed: 12/16/2022] Open
Abstract
Animal venoms are used as defense mechanisms or to immobilize and digest prey. In fact, venoms are complex mixtures of enzymatic and non-enzymatic components with specific pathophysiological functions. Peptide toxins isolated from animal venoms target mainly ion channels, membrane receptors and components of the hemostatic system with high selectivity and affinity. The present review shows an up-to-date survey on the pharmacology of snake-venom bioactive components and evaluates their therapeutic perspectives against a wide range of pathophysiological conditions. Snake venoms have also been used as medical tools for thousands of years especially in tradition Chinese medicine. Consequently, snake venoms can be considered as mini-drug libraries in which each drug is pharmacologically active. However, less than 0.01% of these toxins have been identified and characterized. For instance, Captopril® (Enalapril), Integrilin® (Eptifibatide) and Aggrastat® (Tirofiban) are drugs based on snake venoms, which have been approved by the FDA. In addition to these approved drugs, many other snake venom components are now involved in preclinical or clinical trials for a variety of therapeutic applications. These examples show that snake venoms can be a valuable source of new principle components in drug discovery.
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27
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Trento MVC, Sales TA, de Abreu TS, Braga MA, Cesar PHS, Marques TR, Marcussi S. Exploring the structural and functional aspects of the phospholipase A 2 from Naja spp. Int J Biol Macromol 2019; 140:49-58. [PMID: 31421173 DOI: 10.1016/j.ijbiomac.2019.08.125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 01/22/2023]
Abstract
Naja spp. venom is a natural source of active compounds with therapeutic application potential. Phospholipase A2 (PLA2) is abundant in the venom of Naja spp. and can perform neurotoxicity, cytotoxicity, cardiotoxicity, and hematological disorders. The PLA2s from Naja spp. venoms are Asp 49 isoenzymes with the exception of PLA2 Cys 49 from Naja sagittifera. When looking at the functional aspects, the neurotoxicity occurs by PLA2 called β-toxins that have affinity for phosphatidylcholine in nerve endings and synaptosomes membranes, and by α-toxins that block the nicotinic acetylcholine receptors in the neuromuscular junctions. In addition, these neurotoxins may inhibit K+ and Ca++ channels or even interfere with the Na+/K+/ATPase enzyme. The disturbance in the membrane fluidity also results in inhibition of the release of acetylcholine. The PLA2 can act as anticoagulants or procoagulant. The cytotoxicity exerted by PLA2s result from changes in the cardiomyocyte membranes, triggering cardiac failure and hemolysis. The antibacterial activity, however, is the result of alterations that decrease the stability of the lipid bilayer. Thus, the understanding of the structural and functional aspects of PLA2s can contribute to studies on the toxic and therapeutic mechanisms involved in the envenomation by Naja spp. and in the treatment of pathologies.
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Affiliation(s)
- Marcus Vinícius Cardoso Trento
- Biochemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil.
| | - Thais Aparecida Sales
- Computational Chemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil
| | - Tatiane Silva de Abreu
- Biochemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil
| | - Mariana Aparecida Braga
- Biochemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil
| | - Pedro Henrique Souza Cesar
- Biochemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil
| | - Tamara Rezende Marques
- Biochemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil
| | - Silvana Marcussi
- Biochemistry Laboratory, Department of Chemistry, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais 37200-000, Brazil
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28
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Ayvazyan NM, O'Leary VB, Dolly JO, Ovsepian SV. Neurobiology and therapeutic utility of neurotoxins targeting postsynaptic mechanisms of neuromuscular transmission. Drug Discov Today 2019; 24:1968-1984. [PMID: 31247153 DOI: 10.1016/j.drudis.2019.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 05/15/2019] [Accepted: 06/17/2019] [Indexed: 11/28/2022]
Abstract
The neuromuscular junction (NMJ) is the principal site for the translation of motor neurochemical signals to muscle activity. Therefore, the release and sensing machinery of acetylcholine (ACh) along with muscle contraction are two of the main targets of natural toxins and pathogens, causing paralysis. Given pharmacology and medical advances, the active ingredients of toxins that target postsynaptic mechanisms have become of major interest, showing promise as drug leads. Herein, we review key facets of prevalent toxins modulating the mechanisms of ACh sensing and generation of the postsynaptic response, with muscle contraction. We consider the correlation between their outstanding selectivity and potency plus effects on motor function, and discuss emerging data advocating their usage for the development of therapies alleviating neuromuscular dysfunction.
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Affiliation(s)
- Naira M Ayvazyan
- Orbeli Institute of Physiology, National Academy of Sciences of the Republic of Armenia, Yerevan, Armenia.
| | - Valerie B O'Leary
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Ruská 87, 100 00, Praha 10, Czech Republic
| | - J Oliver Dolly
- International Centre for Neurotherapeutics, Dublin City University, Dublin, Ireland
| | - Saak V Ovsepian
- International Centre for Neurotherapeutics, Dublin City University, Dublin, Ireland; The National Institute of Mental Health, Topolová 748, Klecany, Czech Republic; Department of Psychiatry and Medical Psychology, Third Faculty of Medicine, Charles University, Ruská 87, 100 00, Praha 10, Czech Republic.
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29
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Naja atra cardiotoxins enhance the protease activity of chymotrypsin. Int J Biol Macromol 2019; 136:512-520. [PMID: 31199971 DOI: 10.1016/j.ijbiomac.2019.06.066] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/27/2019] [Accepted: 06/11/2019] [Indexed: 02/03/2023]
Abstract
Snake venom cardiotoxins (CTXs) present diverse pharmacological functions. Previous studies have reported that CTXs affect the activity of some serine proteases, namely, chymotrypsin, subtilisin, trypsin, and acetylcholinesterase. To elucidate the mode of action of CTXs, the interaction of CTXs with chymotrypsin was thus investigated. It was found that Naja atra CTX isotoxins concentration-dependently enhanced chymotrypsin activity. The capability of CTX1 and CTX5 in increasing chymotrypsin activity was higher than that of CTX2, CTX3, and CTX4. Removal of the molecular beacon-bound CTXs by chymotrypsin, circular dichroism measurement, and acrylamide quenching of Trp fluorescence indicated that CTXs bound to chymotrypsin. Chemical modification of Lys, Arg, or Met residues of CTX1 attenuated its capability to enhance chymotrypsin activity without impairing their bond with chymotrypsin. Catalytically inactive chymotrypsin retained the binding affinity for native and modified CTX1. CTX1 and chemically modified CTX1 differently altered the global conformation of chymotrypsin and inactivated chymotrypsin. Moreover, CTX1 did not reduce the interaction of 2-(p-toluidino)-naphthalene-6-sulfonate (TNS) with chymotrypsin and inactivated chymotrypsin. Together with previous results revealing that TNS can bind at the hydrophobic region of active site in chymotrypsin, our data suggest that CTXs can enhance chymotrypsin activity by binding to the region outside the enzyme's active site.
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30
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Roy A, Qingxiang S, Alex C, Rajagopalan N, Jobichen C, Sivaraman J, Kini RM. Identification of a α-helical molten globule intermediate and structural characterization of β-cardiotoxin, an all β-sheet protein isolated from the venom of Ophiophagus hannah (king cobra). Protein Sci 2019; 28:952-963. [PMID: 30891862 PMCID: PMC6459992 DOI: 10.1002/pro.3605] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 03/12/2019] [Accepted: 03/19/2019] [Indexed: 02/05/2023]
Abstract
β-Cardiotoxin is a novel member of the snake venom three-finger toxin (3FTX) family. This is the first exogenous protein to antagonize β-adrenergic receptors and thereby causing reduction in heart rates (bradycardia) when administered into animals, unlike the conventional cardiotoxins as reported earlier. 3FTXs are stable all β-sheet peptides with 60-80 amino acid residues. Here, we describe the three-dimensional crystal structure of β-cardiotoxin together with the identification of a molten globule intermediate in the unfolding pathway of this protein. In spite of the overall structural similarity of this protein with conventional cardiotoxins, there are notable differences observed at the loop region and in the charge distribution on the surface, which are known to be critical for cytolytic activity of cardiotoxins. The molten globule intermediate state present in the thermal unfolding pathway of β-cardiotoxin was however not observed during the chemical denaturation of the protein. Interestingly, circular dichroism (CD) and NMR studies revealed the presence of α-helical secondary structure in the molten globule intermediate. These results point to substantial conformational plasticity of β-cardiotoxin, which might aid the protein in responding to the sometimes conflicting demands of structure, stability, and function during its biological lifetime.
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Affiliation(s)
- Amrita Roy
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
| | - Sun Qingxiang
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
- Department of PathologyWest China Hospital, Sichuan UniversityChengduChina 610041
| | - Chapeaurouge Alex
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
- Fundação Oswaldo Cruz‐CearáRua São José, 2° Pavimento, PrecaburaEusébio 61760‐000Brazil
| | - Nandhakishore Rajagopalan
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
- National Research Council of CanadaCanada
| | - Chacko Jobichen
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
| | - J. Sivaraman
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
| | - R. Manjunatha Kini
- Department of Biological Sciences, Faculty of ScienceNational University of SingaporeSingapore 117543
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Dubovskii PV, Efremov RG. The role of hydrophobic /hydrophilic balance in the activity of structurally flexible vs. rigid cytolytic polypeptides and analogs developed on their basis. Expert Rev Proteomics 2018; 15:873-886. [PMID: 30328726 DOI: 10.1080/14789450.2018.1537786] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Being important representatives of various proteomes, membrane-active cationic peptides (CPs) are attractive objects as lead compounds in the design of new antibacterial, anticancer, antifungal, and antiviral molecules. Numerous CPs are found in insect and snake venoms, where many of them reveal cytolytic properties. Due to advances in omics technologies, the number of such peptides is growing dramatically. Areas covered: To understand structure-function relationships for CPs in a living cell, detailed analysis of their hydrophobic/hydrophilic properties is indispensable. We consider two structural classes of membrane-active CPs: latarcins (Ltc) from spider and cardiotoxins (CTXs) from snake venoms. While the former are void off disulfide bonds and conformationally flexible, the latter are structurally rigid and cross-linked with disulfide bonds. In order to elucidate structure-activity relationships behind their antibacterial, anticancer, and hemolytic effects, the properties of these polypeptides are considered on a side-by-side basis. Expert commentary: An ever-increasing number of venom-derived membrane-active polypeptides require new methods for identification of their functional propensities and sequence-based design of novel pharmacological substances. We address these issues considering a number of the designed peptides, based either on Ltc or CTX sequences. Experimental and computer modeling techniques required for these purposes are delineated.
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Affiliation(s)
- Peter V Dubovskii
- a Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry , Russian Academy of Sciences , Moscow , Russia
| | - Roman G Efremov
- a Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry , Russian Academy of Sciences , Moscow , Russia.,b Moscow Institute of Physics and Technology , Dolgoprudnyi , Russian Federation.,c National Research University Higher School of Economics , Moscow , Russia
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32
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Engineered nanoparticles bind elapid snake venom toxins and inhibit venom-induced dermonecrosis. PLoS Negl Trop Dis 2018; 12:e0006736. [PMID: 30286075 PMCID: PMC6171825 DOI: 10.1371/journal.pntd.0006736] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 08/07/2018] [Indexed: 11/19/2022] Open
Abstract
Envenomings by snakebites constitute a serious and challenging global health issue. The mainstay in the therapy of snakebite envenomings is the parenteral administration of animal-derived antivenoms. Significantly, antivenoms are only partially effective in the control of local tissue damage. A novel approach to mitigate the progression of local tissue damage that could complement the antivenom therapy of envenomings is proposed. We describe an abiotic hydrogel nanoparticle engineered to bind to and modulate the activity of a diverse array of PLA2 and 3FTX isoforms found in Elapidae snake venoms. These two families of protein toxins share features that are associated with their common (membrane) targets, allowing for nanoparticle sequestration by a mechanism that differs from immunological (epitope) selection. The nanoparticles are non-toxic in mice and inhibit dose-dependently the dermonecrotic activity of Naja nigricollis venom.
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Abstract
The neurotransmitter acetylcholine (ACh) acts as an autocrine growth factor for human lung cancer. Several lines of evidence show that lung cancer cells express all of the proteins required for the uptake of choline (choline transporter 1, choline transporter-like proteins) synthesis of ACh (choline acetyltransferase, carnitine acetyltransferase), transport of ACh (vesicular acetylcholine transport, OCTs, OCTNs) and degradation of ACh (acetylcholinesterase, butyrylcholinesterase). The released ACh binds back to nicotinic (nAChRs) and muscarinic receptors on lung cancer cells to accelerate their proliferation, migration and invasion. Out of all components of the cholinergic pathway, the nAChR-signaling has been studied the most intensely. The reason for this trend is due to genome-wide data studies showing that nicotinic receptor subtypes are involved in lung cancer risk, the relationship between cigarette smoke and lung cancer risk as well as the rising popularity of electronic cigarettes considered by many as a "safe" alternative to smoking. There are a small number of articles which review the contribution of the other cholinergic proteins in the pathophysiology of lung cancer. The primary objective of this review article is to discuss the function of the acetylcholine-signaling proteins in the progression of lung cancer. The investigation of the role of cholinergic network in lung cancer will pave the way to novel molecular targets and drugs in this lethal malignancy.
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Choudhury M, McCleary RJR, Kini RM, Velmurugan D. Orphan Three-Finger Toxins Bind at Tissue Factor-Factor VIIa Interface to Inhibit Factor X Activation: Identification of Functional Site by Docking. TH OPEN 2018; 2:e303-e314. [PMID: 31249954 PMCID: PMC6524886 DOI: 10.1055/s-0038-1672184] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 08/03/2018] [Indexed: 02/03/2023] Open
Abstract
Three-finger toxins (3FTxs) contribute to toxicity of venomous snakes belonging to the family Elapidae. Currently, functions of a considerable proportion of 3FTxs are still unknown. Here, we describe the function of orphan group I 3FTxs consisting of four members. We also identified a new member of this group by sequencing a transcript isolated from Naja naja venom. This transcript, named najalexin, is identical to that previously described 3FTx from Naja atra venom gland, and shared high sequence identity with ringhalexin from Hemachatus haemachatus and a hypothetical protein from Ophiophagus hannah (here named as ophiolexin). The three-dimensional structure, as predicted by molecular modeling, showed that najalexin and ophiolexin share the same conserved structural organization as ringhalexin and other 3FTxs. Since ringhalexin inhibits the activation of factor X by the tissue factor-factor VIIa complex (TF-FVIIa), we evaluated the interaction of this group of 3FTxs with all components using in silico protein-protein docking studies. The binding of orphan group I 3FTxs to TF-FVIIa complex appears to be driven by their interaction with TF. They bind to fibronectin domain closer to the 170-loop of the FVIIa heavy chain to inhibit factor X activation. The docking studies reveal that functional site residues Tyr7, Lys9, Glu12, Lys26, Arg34, Leu35, Arg40, Val55, Asp56, Cys57, Cys58, and Arg65 on these 3FTxs are crucial for interaction. In silico replacement of these residues by Ala resulted in significant effects in the binding energies. Furthermore, these functional residues are not found in other groups of 3FTxs, which exhibit distinct pharmacological properties.
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Affiliation(s)
- Manisha Choudhury
- CAS in Crystallography and Biophysics, University of Madras, Chennai, Tamil Nadu, India
| | - Ryan J. R. McCleary
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Department of Biology, Stetson University, DeLand, Florida, United States
| | - R. Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Devadasan Velmurugan
- CAS in Crystallography and Biophysics, University of Madras, Chennai, Tamil Nadu, India
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Guerrero-Garzón JF, Bénard-Valle M, Restano-Cassulini R, Zamudio F, Corzo G, Alagón A, Olvera-Rodríguez A. Cloning and sequencing of three-finger toxins from the venom glands of four Micrurus species from Mexico and heterologous expression of an alpha-neurotoxin from Micrurus diastema. Biochimie 2018; 147:114-121. [DOI: 10.1016/j.biochi.2018.01.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 01/24/2018] [Indexed: 11/25/2022]
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36
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Ly S, Pack AI, Naidoo N. The neurobiological basis of sleep: Insights from Drosophila. Neurosci Biobehav Rev 2018; 87:67-86. [PMID: 29391183 PMCID: PMC5845852 DOI: 10.1016/j.neubiorev.2018.01.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/22/2018] [Accepted: 01/24/2018] [Indexed: 12/12/2022]
Abstract
Sleep is a biological enigma that has raised numerous questions about the inner workings of the brain. The fundamental question of why our nervous systems have evolved to require sleep remains a topic of ongoing scientific deliberation. This question is largely being addressed by research using animal models of sleep. Drosophila melanogaster, also known as the common fruit fly, exhibits a sleep state that shares common features with many other species. Drosophila sleep studies have unearthed an immense wealth of knowledge about the neuroscience of sleep. Given the breadth of findings published on Drosophila sleep, it is important to consider how all of this information might come together to generate a more holistic understanding of sleep. This review provides a comprehensive summary of the neurobiology of Drosophila sleep and explores the broader insights and implications of how sleep is regulated across species and why it is necessary for the brain.
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Affiliation(s)
- Sarah Ly
- Center for Sleep and Circadian Neurobiology, 125 South 31st St., Philadelphia, PA, 19104-3403, United States.
| | - Allan I Pack
- Center for Sleep and Circadian Neurobiology, 125 South 31st St., Philadelphia, PA, 19104-3403, United States; Division of Sleep Medicine/Department of Medicine, University of Pennsylvania Perelman School of Medicine, 125 South 31st St., Philadelphia, PA, 19104-3403, United States
| | - Nirinjini Naidoo
- Center for Sleep and Circadian Neurobiology, 125 South 31st St., Philadelphia, PA, 19104-3403, United States; Division of Sleep Medicine/Department of Medicine, University of Pennsylvania Perelman School of Medicine, 125 South 31st St., Philadelphia, PA, 19104-3403, United States.
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37
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Xiong S, Huang C. Synergistic strategies of predominant toxins in snake venoms. Toxicol Lett 2018; 287:142-154. [PMID: 29428543 DOI: 10.1016/j.toxlet.2018.02.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 01/17/2018] [Accepted: 02/03/2018] [Indexed: 12/22/2022]
Abstract
Synergism is a significant phenomenon present in snake venoms that may be an evolving strategy to potentiate toxicities. Synergism exists between different toxins or toxin complexes in various snake venoms, with phospholipaseA2s (PLA2s) (toxins or subunits) the main enablers. The predominant toxins, snake venom PLA2s, metalloproteases (SVMPs), serine proteases (SVSPs) and three-finger toxins (3FTxs), play essential roles in synergistic processes. The hypothetical mechanisms of synergistic effect can be generalized under the effects of amplification and chaperoning. The Toxicity Score is among the few quantitative methods to assess synergism. Selection of toxins involved in synergistically enhanced toxicity as the targets are important for development of novel antivenoms or inhibitors.
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Affiliation(s)
- Shengwei Xiong
- College of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi Province, China
| | - Chunhong Huang
- College of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi Province, China.
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Ruan H, Ueda A, Xing X, Wan X, Strub B, Mukai S, Certel K, Green D, Belozerov K, Yao WD, Johnson W, Jung-Ching Lin J, Hilliker AJ, Wu CF. Generation and characterization of new alleles of quiver (qvr) that encodes an extracellular modulator of the Shaker potassium channel. J Neurogenet 2017; 31:325-336. [PMID: 29117754 DOI: 10.1080/01677063.2017.1393076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Our earlier genetic screen uncovered a paraquat-sensitive leg-shaking mutant quiver1 (qvr1), whose gene product interacts with the Shaker (Sh) K+ channel. We also mapped the qvr locus to EY04063 and noticed altered day-night activity patterns in these mutants. Such circadian behavioral defects were independently reported by another group, who employed the qvr1 allele we supplied them, and attributed the extreme restless phenotype of EY04063 to the qvr gene. However, their report adopted a new noncanonical gene name sleepless (sss) for qvr. In addition to qvr1 and qvrEY, our continuous effort since the early 2000s generated a number of novel recessive qvr alleles, including ethyl methanesulfonate (EMS)-induced mutations qvr2 and qvr3, and P-element excision lines qvrip6 (imprecise jumpout), qvrrv7, and qvrrv9 (revertants) derived from qvrEY. Distinct from the original intron-located qvr1 allele that generates abnormal-sized mRNAs, qvr2, and qvr3 had their lesion sites in exons 6 and 7, respectively, producing nearly normal-sized mRNA products. A set of RNA-editing sites are nearby the lesion sites of qvr3 and qvrEY on exon 7. Except for the revertants, all qvr alleles display a clear ether-induced leg-shaking phenotype just like Sh, and weakened climbing abilities to varying degrees. Unlike Sh, all shaking qvr alleles (except for qvrf01257) displayed a unique activity-dependent enhancement in excitatory junction potentials (EJPs) at larval neuromuscular junctions (NMJs) at very low stimulus frequencies, with qvrEY displaying the largest EJP and more significant NMJ overgrowth than other alleles. Our detailed characterization of a collection of qvr alleles helps to establish links between novel molecular lesions and different behavioral and physiological consequences, revealing how modifications of the qvr gene lead to a wide spectrum of phenotypes, including neuromuscular hyperexcitability, defective motor ability and activity-rest cycles.
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Affiliation(s)
- Hongyu Ruan
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Atsushi Ueda
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Xiaomin Xing
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Xuxuan Wan
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Benjamin Strub
- b Department of Biology , York University , Toronto , ON , Canada
| | - Spencer Mukai
- b Department of Biology , York University , Toronto , ON , Canada
| | - Kaan Certel
- c Department of Molecular Physiology and Biophysics , University of Iowa , Iowa City , IA , USA
| | - David Green
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Kyle Belozerov
- b Department of Biology , York University , Toronto , ON , Canada
| | - Wei-Dong Yao
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Wayne Johnson
- c Department of Molecular Physiology and Biophysics , University of Iowa , Iowa City , IA , USA
| | | | | | - Chun-Fang Wu
- a Department of Biology , University of Iowa , Iowa City , IA , USA
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Dutertre S, Nicke A, Tsetlin VI. Nicotinic acetylcholine receptor inhibitors derived from snake and snail venoms. Neuropharmacology 2017. [PMID: 28623170 DOI: 10.1016/j.neuropharm.2017.06.011] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The nicotinic acetylcholine receptor (nAChR) represents the prototype of ligand-gated ion channels. It is vital for neuromuscular transmission and an important regulator of neurotransmission. A variety of toxic compounds derived from diverse species target this receptor and have been of elemental importance in basic and applied research. They enabled milestone discoveries in pharmacology and biochemistry ranging from the original formulation of the receptor concept, the first isolation and structural analysis of a receptor protein (the nAChR) to the identification, localization, and differentiation of its diverse subtypes and their validation as a target for therapeutic intervention. Among the venom-derived compounds, α-neurotoxins and α-conotoxins provide the largest families and still represent indispensable pharmacological tools. Application of modified α-neurotoxins provided substantial structural and functional details of the nAChR long before high resolution structures were available. α-bungarotoxin represents not only a standard pharmacological tool and label in nAChR research but also for unrelated proteins tagged with a minimal α-bungarotoxin binding motif. A major advantage of α-conotoxins is their smaller size, as well as superior selectivity for diverse nAChR subtypes that allows their development into ligands with optimized pharmacological and chemical properties and potentially novel drugs. In the following, these two groups of nAChR antagonists will be described focusing on their respective roles in the structural and functional characterization of nAChRs and their development into research tools. In addition, we provide a comparative overview of the diverse α-conotoxin selectivities that can serve as a practical guide for both structure activity studies and subtype classification. This article is part of the Special Issue entitled 'Venom-derived Peptides as Pharmacological Tools.'
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Affiliation(s)
- Sébastien Dutertre
- Institut des Biomolécules Max Mousseron, UMR 5247, Université Montpellier - CNRS, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France
| | - Annette Nicke
- Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Nußbaumstr. 26, 80336 Munich, Germany.
| | - Victor I Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str.16/10, Moscow 117999, Russian Federation
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Gorai B, Sivaraman T. Delineating residues for haemolytic activities of snake venom cardiotoxin 1 from Naja naja as probed by molecular dynamics simulations and in vitro validations. Int J Biol Macromol 2017; 95:1022-1036. [DOI: 10.1016/j.ijbiomac.2016.10.091] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/26/2016] [Indexed: 02/05/2023]
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Shi YJ, Chen YJ, Hu WP, Chang LS. Detection of Naja atra Cardiotoxin Using Adenosine-Based Molecular Beacon. Toxins (Basel) 2017; 9:toxins9010024. [PMID: 28067855 PMCID: PMC5308256 DOI: 10.3390/toxins9010024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 01/02/2017] [Accepted: 01/04/2017] [Indexed: 02/07/2023] Open
Abstract
This study presents an adenosine (A)-based molecular beacon (MB) for selective detection of Naja atra cardiotoxin (CTX) that functions by utilizing the competitive binding between CTX and the poly(A) stem of MB to coralyne. The 5′- and 3′-end of MB were labeled with a reporter fluorophore and a non-fluorescent quencher, respectively. Coralyne induced formation of the stem-loop MB structure through A2-coralyne-A2 coordination, causing fluorescence signal turn-off due to fluorescence resonance energy transfer between the fluorophore and quencher. CTX3 could bind to coralyne. Moreover, CTX3 alone induced the folding of MB structure and quenching of MB fluorescence. Unlike that of snake venom α-neurotoxins, the fluorescence signal of coralyne-MB complexes produced a bell-shaped concentration-dependent curve in the presence of CTX3 and CTX isotoxins; a turn-on fluorescence signal was noted when CTX concentration was ≤80 nM, while a turn-off fluorescence signal was noted with a further increase in toxin concentrations. The fluorescence signal of coralyne-MB complexes yielded a bell-shaped curve in response to varying concentrations of N. atra crude venom but not those of Bungarus multicinctus and Protobothrops mucrosquamatus venoms. Moreover, N. nigricollis venom also functioned as N. atra venom to yield a bell-shaped concentration-dependent curve of MB fluorescence signal, again supporting that the hairpin-shaped MB could detect crude venoms containing CTXs. Taken together, our data validate that a platform composed of coralyne-induced stem-loop MB structure selectively detects CTXs.
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Affiliation(s)
- Yi-Jun Shi
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Ying-Jung Chen
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Wan-Ping Hu
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
| | - Long-Sen Chang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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Lauridsen LP, Laustsen AH, Lomonte B, Gutiérrez JM. Exploring the venom of the forest cobra snake: Toxicovenomics and antivenom profiling of Naja melanoleuca. J Proteomics 2017; 150:98-108. [DOI: 10.1016/j.jprot.2016.08.024] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 11/28/2022]
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Chakraborty S, Nag D, Mazumder TH, Uddin A. Codon usage pattern and prediction of gene expression level in Bungarus species. Gene 2016; 604:48-60. [PMID: 27845207 DOI: 10.1016/j.gene.2016.11.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 10/18/2016] [Accepted: 11/10/2016] [Indexed: 10/20/2022]
Abstract
Codon bias study in an organism gains significance in understanding the molecular mechanism as well as the functional conservation of gene expression during the course of evolution. The prime focus in this study is to compare the codon usage patterns among the four species belonging to the genus Bungarus (B. multicinctus, B. fasciatus, B. candidus and B. flaviceps) using several codon bias parameters. Our results suggested that relatively low codon bias exists in the coding sequences of the selected species. The compositional constraints together with gene expression level might influence the patterns of codon usage among the genes of Bungarus species. Both natural selection and mutation pressure affect the codon usage pattern in Bungarus species as evident from correspondence analysis. Neutrality plot indicates that natural selection played a major role while mutation pressure played a minor role in codon usage pattern of the genes in Bungarus species.
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Affiliation(s)
- Supriyo Chakraborty
- Department of Biotechnology, Assam University, Silchar, Assam 788011, India.
| | - Debojyoti Nag
- Department of Biotechnology, Assam University, Silchar, Assam 788011, India
| | | | - Arif Uddin
- Department of Biotechnology, Assam University, Silchar, Assam 788011, India; Moinul Hoque Choudhury Memorial Science College, Algapur, HailaKandi, Assam 788150, India
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Webb DR. Soluble Immune Response Suppressor (SIRS): Reassessing the immunosuppressant potential of an elusive peptide. Biochem Pharmacol 2016; 117:1-9. [PMID: 27038657 DOI: 10.1016/j.bcp.2016.03.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 03/28/2016] [Indexed: 11/30/2022]
Abstract
A previously studied immunosuppressive cytokine, Soluble Immune Response Suppressor (SIRS), may have relevance to current studies of immune suppression in a variety of human disease states. Despite extensive efforts using experimental models, mainly in mice, much remains to be discovered as to how autoimmune cells in mice and humans escape normal regulation and, conversely, how tumor cells evade evoking an immune response. It is the contention of this commentary that the literature pre-2000 contain results that might inform current studies. The broadly immunosuppressive protein, SIRS, was studied extensively from the 1970s to 1990s and culminated in the determination of the n-terminal 21mer sequence of this 15kDa protein which had high homology to the short neurotoxins from sea snakes, that are canonical members of the three finger neurotoxin superfamily (3FTx). It was not until 2007 that the prophylactic administration of the synthetic N-terminal peptide of the SIRS 21mer, identical to the published sequence, was reported to inhibit or delay the development of two autoimmune diseases in mice: experimental allergic encephalomyelitis (EAE) and type I diabetes (T1D). These findings were consistent with other studies of the 3FTx superfamily as important probes in the study of mammalian pharmacology. It is the perspective of this commentary that SIRS, SIRS peptide and the anti-peptide mAb, represent useful, pharmacologically-active probes for the study of the immune response as well as in the potential treatment of autoimmune, inflammatory diseases and cancer.
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Affiliation(s)
- David R Webb
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 N. Torrey Pines Rd, La Jolla, CA 92037, United States.
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45
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Shulepko MA, Lyukmanova EN, Shenkarev ZO, Dubovskii PV, Astapova MV, Feofanov AV, Arseniev AS, Utkin YN, Kirpichnikov MP, Dolgikh DA. Towards universal approach for bacterial production of three-finger Ly6/uPAR proteins: Case study of cytotoxin I from cobra N. oxiana. Protein Expr Purif 2016; 130:13-20. [PMID: 27702601 DOI: 10.1016/j.pep.2016.09.021] [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] [Received: 08/01/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 01/26/2023]
Abstract
Cytotoxins or cardiotoxins is a group of polycationic toxins from cobra venom belonging to the 'three-finger' protein superfamily (Ly6/uPAR family) which includes small β-structural proteins (60-90 residues) with high disulfide bond content (4-5 disulfides). Due to a high cytotoxic activity for cancer cells, cytotoxins are considered as potential anticancer agents. Development of the high-throughput production methods is required for the prospective applications of cytotoxins. Here, efficient approach for bacterial production of recombinant analogue of cytotoxin I from N. oxiana containing additional N-terminal Met-residue (rCTX1) was developed. rCTX1 was produced in the form of E. coli inclusion bodies. Refolding in optimized conditions provided ∼6 mg of correctly folded protein from 1 L of bacterial culture. Cytotoxicity of rCTX1 for C6 rat glioma cells was found to be similar to the activity of wild type CTX1. The milligram quantities of 13C,15N-labeled rCTX1 were obtained. NMR study confirmed the similarity of the spatial structures of recombinant and wild-type toxins. Additional Met residue does not perturb the overall structure of the three-finger core. The analysis of available data for different Ly6/uPAR proteins of snake and human origin revealed that efficiency of their folding in vitro is correlated with the number of proline residues in the third loop and the surface area of hydrophobic residues buried within the protein interior. The obtained data indicate that hydrophobic core is important for the folding of proteins with high disulfide bond content. Developed expression method opens new possibilities for structure-function studies of CTX1 and other related three-finger proteins.
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Affiliation(s)
- M A Shulepko
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - E N Lyukmanova
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia.
| | - Z O Shenkarev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia; Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region, 141700, Russia
| | - P V Dubovskii
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - M V Astapova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - A V Feofanov
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - A S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia; Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region, 141700, Russia
| | - Y N Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - M P Kirpichnikov
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - D A Dolgikh
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
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Arvaniti M, Jensen MM, Soni N, Wang H, Klein AB, Thiriet N, Pinborg LH, Muldoon PP, Wienecke J, Imad Damaj M, Kohlmeier KA, Gondré-Lewis MC, Mikkelsen JD, Thomsen MS. Functional interaction between Lypd6 and nicotinic acetylcholine receptors. J Neurochem 2016; 138:806-20. [PMID: 27344019 PMCID: PMC5017906 DOI: 10.1111/jnc.13718] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 06/22/2016] [Accepted: 06/24/2016] [Indexed: 01/15/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) affect multiple physiological functions in the brain and their functions are modulated by regulatory proteins of the Lynx family. Here, we report for the first time a direct interaction of the Lynx protein LY6/PLAUR domain-containing 6 (Lypd6) with nAChRs in human brain extracts, identifying Lypd6 as a novel regulator of nAChR function. Using protein cross-linking and affinity purification from human temporal cortical extracts, we demonstrate that Lypd6 is a synaptically enriched membrane-bound protein that binds to multiple nAChR subtypes in the human brain. Additionally, soluble recombinant Lypd6 protein attenuates nicotine-induced hippocampal inward currents in rat brain slices and decreases nicotine-induced extracellular signal-regulated kinase phosphorylation in PC12 cells, suggesting that binding of Lypd6 is sufficient to inhibit nAChR-mediated intracellular signaling. We further show that perinatal nicotine exposure in rats (4 mg/kg/day through minipumps to dams from embryonic day 7 to post-natal day 21) significantly increases Lypd6 protein levels in the hippocampus in adulthood, which did not occur after exposure to nicotine in adulthood only. Our findings suggest that Lypd6 is a versatile inhibitor of cholinergic signaling in the brain, and that Lypd6 is dysregulated by nicotine exposure during early development. Regulatory proteins of the Lynx family modulate the function of nicotinic receptors (nAChRs). We report for the first time that the Lynx protein Lypd6 binds to nAChRs in human brain extracts, and that recombinant Lypd6 decreases nicotine-induced ERK phosphorylation and attenuates nicotine-induced hippocampal inward currents. Our findings suggest that Lypd6 is a versatile inhibitor of cholinergic signaling in the brain.
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Affiliation(s)
- Maria Arvaniti
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Majbrit M Jensen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Neeraj Soni
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Hong Wang
- Laboratory for Neurodevelopment, Department of Anatomy, Howard University College of Medicine, Washington, District of Columbia, USA
| | - Anders B Klein
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Nathalie Thiriet
- Laboratory of Experimental and Clinical Neurosciences, University of Poitiers, Poitiers, France
| | - Lars H Pinborg
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark.,Epilepsy Clinic, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Pretal P Muldoon
- Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Jacob Wienecke
- Department of Nutrition, Exercise and Sport & Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - M Imad Damaj
- Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Kristi A Kohlmeier
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Marjorie C Gondré-Lewis
- Laboratory for Neurodevelopment, Department of Anatomy, Howard University College of Medicine, Washington, District of Columbia, USA
| | - Jens D Mikkelsen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Morten S Thomsen
- Department of Drug Design & Pharmacology, University of Copenhagen, Copenhagen, Denmark. .,Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark.
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Wang M, Li L, Guo Q, Zhang S, Ji D, Li H. Identification and expression of a new Ly6 gene cluster in zebrafish Danio rerio, with implications of being involved in embryonic immunity. FISH & SHELLFISH IMMUNOLOGY 2016; 54:230-240. [PMID: 27071517 DOI: 10.1016/j.fsi.2016.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/29/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
Lymphocyte antigen-6 (Ly6) superfamily is a large family of proteins and characterized by precisely spaced cysteine motifs, termed the three-finger fold. To date, a large number of members of the Ly6/uPAR family were identified among many species. In this study, we first report the identification and characterization of the secreted Ly2.1-3 proteins on the chromosome 2 in zebrafish and determine the expression pattern. Ly2.1-3 all possess a conserved LU domain and adopt similar three-finger structure with human CD59, SLURP1 and other Ly6 family members. Ly2.1-3 cluster on chromosome 2 and share high homology, possibly originated from chromosomal gene duplication. Ly2.1-3 exhibit distinct expression pattern in the endoderm, they were found abundantly and specifically in the digestive tract, liver and pancreas respectively. The differential expression pattern may suggest Ly2.1-3 acquire new function during gene duplication. The expression level of Ly2.1-3 were up-regulating challenged with LPS indicated that they have a role in innate immune responses of the digestive system during endotoxin challenge in early stage.
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Affiliation(s)
- Man Wang
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Lingyi Li
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Quanyang Guo
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Shicui Zhang
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China
| | - Dongrui Ji
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
| | - Hongyan Li
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Laboratory for Evolution & Development, Department of Marine Biology, Ocean University of China, Qingdao 266003, China.
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48
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Barnwal B, Jobichen C, Girish VM, Foo CS, Sivaraman J, Kini RM. Ringhalexin from Hemachatus haemachatus: A novel inhibitor of extrinsic tenase complex. Sci Rep 2016; 6:25935. [PMID: 27173146 PMCID: PMC4865804 DOI: 10.1038/srep25935] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 04/26/2016] [Indexed: 12/15/2022] Open
Abstract
Anticoagulant therapy is used for the prevention and treatment of thromboembolic disorders. Blood coagulation is initiated by the interaction of factor VIIa (FVIIa) with membrane-bound tissue factor (TF) to form the extrinsic tenase complex which activates FX to FXa. Thus, it is an important target for the development of novel anticoagulants. Here, we report the isolation and characterization of a novel anticoagulant ringhalexin from the venom of Hemachatus haemachatus (African Ringhals Cobra). Amino acid sequence of the protein indicates that it belongs to the three-finger toxin family and exhibits 94% identity to an uncharacterized Neurotoxin-like protein NTL2 from Naja atra. Ringhalexin inhibited FX activation by extrinsic tenase complex with an IC50 of 123.8 ± 9.54 nM. It is a mixed-type inhibitor with the kinetic constants, Ki and Ki' of 84.25 ± 3.53 nM and 152.5 ± 11.32 nM, respectively. Ringhalexin also exhibits a weak, irreversible neurotoxicity on chick biventer cervicis muscle preparations. Subsequently, the three-dimensional structure of ringhalexin was determined at 2.95 Å resolution. This study for the first time reports the structure of an anticoagulant three-finger toxin. Thus, ringhalexin is a potent inhibitor of the FX activation by extrinsic tenase complex and a weak, irreversible neurotoxin.
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Affiliation(s)
- Bhaskar Barnwal
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260, Singapore
| | - Chacko Jobichen
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260, Singapore
| | | | - Chun Shin Foo
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260, Singapore
| | - J. Sivaraman
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260, Singapore
| | - R. Manjunatha Kini
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260, Singapore
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49
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Chen C, Hu Y, Shi X, Tao C, Zheng H, Fei W, Han S, Zhu J, Wei Y, Li F. A single-label fluorescent derivatization method for quantitative determination of neurotoxin in vivo by capillary electrophoresis coupled with laser-induced fluorescence detection. Analyst 2016; 141:4495-501. [PMID: 27175860 DOI: 10.1039/c6an00327c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neurotoxin (NT), a short-chain α-neurotoxin, is the main neurotoxic protein identified from the venom of Naja naja atra. As an effective drug for the analgesis of advanced cancer patients, NT lasts longer than morphine and does not cause addiction. However, achieving a sensitive and high-resolution measurement of NT is difficult because of the extra-low content of NT in vivo. Therefore, developing a novel method to quantify NT is essential to study its pharmacokinetics in vivo. Although NT contains four primary amine groups that could react with the thiourea in fluorescein isothiocyanate (FITC), we developed a simple and reproducible single-label fluorescent derivatization method for NT which is related to the reaction of N-terminal α-amino of NT alone under optimized derivatization conditions. Furthermore, neurotoxin labelled with fluorescein isothiocyanate (NT-FITC) was prepared by high-performance liquid chromatography (HPLC) with a purity value higher than 99.29% and identified by MALDI-TOF/TOF-MS. Finally, NT-FITC could be detected at 0.8 nmol L(-1) in rat plasma using capillary electrophoresis coupled with laser induced fluorescence detection (CE-LIF). In this paper, the established method robustly and reliably quantified NT labelled with FITC via intravenous and intramuscular administrations in vivo. In addition, this work fully demonstrated the pharmacokinetic characteristics of NT in vivo, which could reduce the risk of drug accumulation, optimize therapies, and provide sufficient evidence for the rational use of NT in clinical and research laboratories.
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Affiliation(s)
- Cuiwei Chen
- Department of Pharmaceutics, Zhejiang Chinese Medical University, Hangzhou 310053, China.
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Rivera-Torres IO, Jin TB, Cadene M, Chait BT, Poget SF. Discovery and characterisation of a novel toxin from Dendroaspis angusticeps, named Tx7335, that activates the potassium channel KcsA. Sci Rep 2016; 6:23904. [PMID: 27044983 PMCID: PMC4820689 DOI: 10.1038/srep23904] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 03/16/2016] [Indexed: 02/07/2023] Open
Abstract
Due to their central role in essential physiological processes, potassium channels are common targets for animal toxins. These toxins in turn are of great value as tools for studying channel function and as lead compounds for drug development. Here, we used a direct toxin pull-down assay with immobilised KcsA potassium channel to isolate a novel KcsA-binding toxin (called Tx7335) from eastern green mamba snake (Dendroaspis angusticeps) venom. Sequencing of the toxin by Edman degradation and mass spectrometry revealed a 63 amino acid residue peptide with 4 disulphide bonds that belongs to the three-finger toxin family, but with a unique modification of its disulphide-bridge scaffold. The toxin induces a dose-dependent increase in both open probabilities and mean open times on KcsA in artificial bilayers. Thus, it unexpectedly behaves as a channel activator rather than an inhibitor. A charybdotoxin-sensitive mutant of KcsA exhibits similar susceptibility to Tx7335 as wild-type, indicating that the binding site for Tx7335 is distinct from that of canonical pore-blocker toxins. Based on the extracellular location of the toxin binding site (far away from the intracellular pH gate), we propose that Tx7335 increases potassium flow through KcsA by allosterically reducing inactivation of the channel.
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Affiliation(s)
- Iván O. Rivera-Torres
- LaGuardia Community College, City University of New York, Long Island City, NY 11101, USA
| | - Tony B. Jin
- Department of Chemistry, CUNY Graduate Center and Institute for Macromolecular Assemblies, College of Staten Island, City University of New York, Staten Island, NY 10314, USA
| | | | | | - Sébastien F. Poget
- Department of Chemistry, CUNY Graduate Center and Institute for Macromolecular Assemblies, College of Staten Island, City University of New York, Staten Island, NY 10314, USA
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