1
|
Dobson J, Chowdhury A, Tai-A-Pin J, van der Ploeg H, Gillett A, Fry BG. The Clot Thickens: Differential Coagulotoxic and Cardiotoxic Activities of Anguimorpha Lizard Venoms. Toxins (Basel) 2024; 16:283. [PMID: 38922177 PMCID: PMC11209219 DOI: 10.3390/toxins16060283] [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: 05/29/2024] [Revised: 06/11/2024] [Accepted: 06/17/2024] [Indexed: 06/27/2024] Open
Abstract
Despite their evolutionary novelty, lizard venoms are much less studied in comparison to the intense research on snake venoms. While the venoms of helodermatid lizards have long been assumed to be for defensive purposes, there is increasing evidence of toxic activities more useful for predation than defence (such as paralytic neurotoxicity). This study aimed to ascertain the effects of Heloderma, Lanthanotus, and Varanus lizard venoms on the coagulation and cardiovascular systems. Anticoagulant toxicity was demonstrated for the Varanus species studied, with the venoms prolonging clotting times in human and bird plasma due to the destructive cleavage of fibrinogen. In contrast, thromboelastographic analyses on human and bird plasmas in this study demonstrated a procoagulant bioactivity for Heloderma venoms. A previous study on Heloderma venom using factor-depleted plasmas as a proxy model suggested a procoagulant factor was present that activated either Factor XI or Factor XII, but could not ascertain the precise target. Our activation studies using purified zymogens confirmed FXII activation. Comparisons of neonate and adult H. exasperatum, revealed the neonates to be more potent in the ability to activate FXII, being more similar to the venom of the smaller species H. suspectum than the adult H. exasperatum. This suggests potent FXII activation a basal trait in the genus, present in the small bodied last common ancestor. This also indicates an ontogenetic difference in prey preferences in the larger Heloderma species paralleing the change in venom biochemistry. In addition, as birds lack Factor XII, the ability to clot avian plasma suggested an additional procoagulant site of action, which was revealed to be the activation of Factor VII, with H. horridum being the most potent. This study also examined the effects upon the cardiovascular system, including the liberation of kinins from kininogen, which contributes to hypotension induction. This form of toxicity was previously described for Heloderma venoms, and was revealed in this study was to also be a pathophysiological effect of Lanthanotus and Varanus venoms. This suggests that this toxic activity was present in the venom of the last common ancestor of the anguimorph lizards, which is consistent with kallikrein enzymes being a shared toxin trait. This study therefore uncovered novel actions of anguimorph lizard venoms, not only contributing to the evolutionary biology body of knowledge but also revealing novel activities to mine for drug design lead compounds.
Collapse
Affiliation(s)
- James Dobson
- Adaptive Biotoxicology Lab, School of the Environment, University of Queensland, St Lucia, QLD 4072, Australia; (J.D.); (A.C.)
| | - Abhinandan Chowdhury
- Adaptive Biotoxicology Lab, School of the Environment, University of Queensland, St Lucia, QLD 4072, Australia; (J.D.); (A.C.)
| | | | - Harold van der Ploeg
- Working Group Adder Research Netherlands, RAVON, 6525 ED Nijmegen, The Netherlands;
| | - Amber Gillett
- FaunaVet Wildlife Consultancy, Glass House Mountains, QLD 4518, Australia;
| | - Bryan G. Fry
- Adaptive Biotoxicology Lab, School of the Environment, University of Queensland, St Lucia, QLD 4072, Australia; (J.D.); (A.C.)
| |
Collapse
|
2
|
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.
Collapse
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;
| |
Collapse
|
3
|
Messadi E. Snake Venom Components as Therapeutic Drugs in Ischemic Heart Disease. Biomolecules 2023; 13:1539. [PMID: 37892221 PMCID: PMC10605524 DOI: 10.3390/biom13101539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/18/2023] [Accepted: 09/27/2023] [Indexed: 10/29/2023] Open
Abstract
Ischemic heart disease (IHD), especially myocardial infarction (MI), is a leading cause of death worldwide. Although coronary reperfusion is the most straightforward treatment for limiting the MI size, it has nevertheless been shown to exacerbate ischemic myocardial injury. Therefore, identifying and developing therapeutic strategies to treat IHD is a major medical challenge. Snake venoms contain biologically active proteins and peptides that are of major interest for pharmacological applications in the cardiovascular system (CVS). This has led to their use for the development and design of new drugs, such as the first-in-class angiotensin-converting enzyme inhibitor captopril, developed from a peptide present in Bothrops jararaca snake venom. This review discusses the potential usefulness of snake venom toxins for developing effective treatments against IHD and related diseases such as hypertension and atherosclerosis. It describes their biological effects at the molecular scale, their mechanisms of action according to their different pharmacological properties, as well as their subsequent molecular pathways and therapeutic targets. The molecules reported here have either been approved for human medical use and are currently available on the drug market or are still in the clinical or preclinical developmental stages. The information summarized here may be useful in providing insights into the development of future snake venom-derived drugs.
Collapse
Affiliation(s)
- Erij Messadi
- Plateforme de Physiologie et Physiopathologie Cardiovasculaires (P2C), Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université Tunis El Manar, Tunis 1068, Tunisia
| |
Collapse
|
4
|
Hiremath K, Dodakallanavar J, Sampat GH, Patil VS, Harish DR, Chavan R, Hegde HV, Roy S. Three finger toxins of elapids: structure, function, clinical applications and its inhibitors. Mol Divers 2023:10.1007/s11030-023-10734-3. [PMID: 37749455 DOI: 10.1007/s11030-023-10734-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 09/18/2023] [Indexed: 09/27/2023]
Abstract
The WHO lists snakebite as a "neglected tropical disease". In tropical and subtropical areas, envenoming is an important public health issue. This review article describes the structure, function, chemical composition, natural inhibitors, and clinical applications of Elapids' Three Finger Toxins (3FTX) using scientific research data. The primary venomous substance belonging to Elapidae is 3FTX, that targets nAChR. Three parallel β-sheets combine to create 3FTX, which has four or five disulfide bonds. The three primary types of 3FTX are short-chain, long-chain, and nonconventional 3FTX. The functions of 3FTX depend on the specific toxin subtype and the target receptor or ion channel. The well-known effect of 3FTX is probably neurotoxicity because of the severe consequences of muscular paralysis and respiratory failure in snakebite victims. 3FTX have also been studied for their potential clinical applications. α-bungarotoxin has been used as a molecular probe to study the structure and function of nAChRs (Nicotinic Acetylcholine Receptors). Acid-sensing ion channel (ASIC) isoforms 1a and 1b are inhibited by Mambalgins, derived from Black mamba venom, which hinders their function and provide an analgesic effect. α- Cobra toxin is a neurotoxin purified from Chinese cobra (Naja atra) binds to nAChR at the neuronal junction and causes an analgesic effect for moderate to severe pain. Some of the plants and their compounds have been shown to inhibit the activity of 3FTX, and their mechanisms of action are discussed.
Collapse
Affiliation(s)
- Kashinath Hiremath
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
- KLE College of Pharmacy, Belagavi, KLE Academy of Higher Education and Research, Belagavi, Karnataka, 590010, India
| | - Jagadeesh Dodakallanavar
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
- KLE College of Pharmacy, Belagavi, KLE Academy of Higher Education and Research, Belagavi, Karnataka, 590010, India
| | - Ganesh H Sampat
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
- KLE College of Pharmacy, Belagavi, KLE Academy of Higher Education and Research, Belagavi, Karnataka, 590010, India
| | - Vishal S Patil
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
- KLE College of Pharmacy, Belagavi, KLE Academy of Higher Education and Research, Belagavi, Karnataka, 590010, India
| | - Darasaguppe R Harish
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India.
| | - Rajashekar Chavan
- KLE College of Pharmacy, Belagavi, KLE Academy of Higher Education and Research, Belagavi, Karnataka, 590010, India.
| | - Harsha V Hegde
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
| | - Subarna Roy
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
| |
Collapse
|
5
|
Tiwari N, Aggarwal G, Jain GK, Mittal G. Multi-drug loaded microneedles for emergency treatment of snakebite envenomation. Med Hypotheses 2022. [DOI: 10.1016/j.mehy.2022.110908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
6
|
Joglekar AV, Dehari D, Anjum MM, Dulla N, Chaudhuri A, Singh S, Agrawal AK. Therapeutic potential of venom peptides: insights in the nanoparticle-mediated venom formulations. FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2022. [DOI: 10.1186/s43094-022-00415-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Abstract
Background
Venoms are the secretions produced by animals, generally for the purpose of self-defense or catching a prey. Biochemically venoms are mainly composed of proteins, lipids, carbohydrates, ions, etc., and classified into three major classes, viz. neurotoxic, hemotoxic and cytotoxic based upon their mode of action. Venoms are composed of different specific peptides/toxins which are responsible for their unique biological actions. Though venoms are generally seen as a source of death, scientifically venom is a complex biochemical substance having a specific pharmacologic action which can be used as agents to diagnose and cure a variety of diseases in humans.
Main body
Many of these venoms have been used since centuries, and their specified therapies can also be found in ancient texts such as Charka Samhita. The modern-day example of such venom therapeutic is captopril, an antihypertensive drug developed from venom of Bothrops jararaca. Nanotechnology is a modern-day science of building materials on a nanoscale with advantages like target specificity, increased therapeutic response and diminished side effects. In the present review we have introduced the venom, sources and related constituents in brief, by highlighting the therapeutic potential of venom peptides and focusing more on the nanoformulations-based approaches. This review is an effort to compile all such report to have an idea about the future direction about the nanoplatforms which should be focused to have more clinically relevant formulations for difficult to treat diseases.
Conclusion
Venom peptides which are fatal in nature if used cautiously and effectively can save life. Several research findings suggested that many of the fatal diseases can be effectively treated with venom peptides. Nanotechnology has emerged as novel strategy in diagnosis, treatment and mitigation of diseases in more effective ways. A variety of nanoformulation approaches have been explored to enhance the therapeutic efficacy and reduce the toxicity and targeted delivery of the venom peptide conjugated with it. We concluded that venom peptides along with nanoparticles can evolve as the new era for potential treatments of ongoing and untreatable diseases.
Graphical Abstract
Collapse
|
7
|
Assessing the Binding of Venoms from Aquatic Elapids to the Nicotinic Acetylcholine Receptor Orthosteric Site of Different Prey Models. Int J Mol Sci 2020; 21:ijms21197377. [PMID: 33036249 PMCID: PMC7583753 DOI: 10.3390/ijms21197377] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/25/2020] [Accepted: 10/02/2020] [Indexed: 01/19/2023] Open
Abstract
The evolution of an aquatic lifestyle from land dwelling venomous elapids is a radical ecological modification, bringing about many evolutionary changes from morphology to diet. Diet is an important ecological facet which can play a key role in regulating functional traits such as venom composition and prey-specific targeting of venom. In addition to predating upon novel prey (e.g., fish, fish eggs and invertebrates), the venoms of aquatic elapids also face the challenge of increased prey-escape potential in the aquatic environment. Thus, despite the independent radiation into an aquatic niche on four separate occasions, the venoms of aquatic elapids are evolving under convergent selection pressures. Utilising a biolayer interferometry binding assay, this study set out to elucidate whether crude venoms from representative aquatic elapids were target-specific to the orthosteric site of postsynaptic nicotinic acetylcholine receptor mimotopes of fish compared to other terrestrial prey types. Representatives of the four aquatic lineages were: aquatic coral snakes representative was Micrurus surinamensis;, sea kraits representative was Laticauda colubrina; sea snakes representatives were two Aipysurus spp. and eight Hydrophis spp; and water cobras representative was Naja annulata. No prey-specific differences in crude venom binding were observed from any species tested, except for Aipysurus laevis, which showed slight evidence of prey-potency differences. For Hydrophis caerulescens, H. peronii, H. schistosus and M. surinamensis, there was a lack of binding to the orthosteric site of any target lineage. Subsequent testing on the in vitro chick-biventer cervicis muscle preparation suggested that, while the venoms of these species bound postsynaptically, they bound to allosteric sites rather than orthosteric. Allosteric binding is potentially a weaker but faster-acting form of neurotoxicity and we hypothesise that the switch to allosteric binding is likely due to selection pressures related to prey-escape potential. This research has potentially opened up the possibility of a new functional class of toxins which have never been assessed previously while shedding light on the selection pressures shaping venom evolution.
Collapse
|
8
|
Nirthanan S. Snake three-finger α-neurotoxins and nicotinic acetylcholine receptors: molecules, mechanisms and medicine. Biochem Pharmacol 2020; 181:114168. [PMID: 32710970 DOI: 10.1016/j.bcp.2020.114168] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 12/13/2022]
Abstract
Snake venom three-finger α-neurotoxins (α-3FNTx) act on postsynaptic nicotinic acetylcholine receptors (nAChRs) at the neuromuscular junction (NMJ) to produce skeletal muscle paralysis. The discovery of the archetypal α-bungarotoxin (α-BgTx), almost six decades ago, exponentially expanded our knowledge of membrane receptors and ion channels. This included the localisation, isolation and characterization of the first receptor (nAChR); and by extension, the pathophysiology and pharmacology of neuromuscular transmission and associated pathologies such as myasthenia gravis, as well as our understanding of the role of α-3FNTxs in snakebite envenomation leading to novel concepts of targeted treatment. Subsequent studies on a variety of animal venoms have yielded a plethora of novel toxins that have revolutionized molecular biomedicine and advanced drug discovery from bench to bedside. This review provides an overview of nAChRs and their subtypes, classification of α-3FNTxs and the challenges of typifying an increasing arsenal of structurally and functionally unique toxins, and the three-finger protein (3FP) fold in the context of the uPAR/Ly6/CD59/snake toxin superfamily. The pharmacology of snake α-3FNTxs including their mechanisms of neuromuscular blockade, variations in reversibility of nAChR interactions, specificity for nAChR subtypes or for distinct ligand-binding interfaces within a subtype and the role of α-3FNTxs in neurotoxic envenomation are also detailed. Lastly, a reconciliation of structure-function relationships between α-3FNTx and nAChRs, derived from historical mutational and biochemical studies and emerging atomic level structures of nAChR models in complex with α-3FNTxs is discussed.
Collapse
Affiliation(s)
- Selvanayagam Nirthanan
- School of Medical Science, Griffith Health Group, Griffith University, Gold Coast, Queensland, Australia.
| |
Collapse
|
9
|
Kini RM, Koh CY. Snake venom three-finger toxins and their potential in drug development targeting cardiovascular diseases. Biochem Pharmacol 2020; 181:114105. [PMID: 32579959 DOI: 10.1016/j.bcp.2020.114105] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/13/2020] [Accepted: 06/17/2020] [Indexed: 12/15/2022]
Abstract
Cardiovascular diseases such as coronary and peripheral artery diseases, venous thrombosis, stroke, hypertension, and heart failure are enormous burden to health and economy globally. Snake venoms have been the sources of discovery of successful therapeutics targeting cardiovascular diseases. For example, the first-in-class angiotensin-converting enzyme inhibitor captopril was designed largely based on bradykinin-potentiating peptides from Bothrops jararaca venom. In the recent years, sensitive and high throughput approaches drive discovery and cataloging of new snake venom toxins. As one of the largest class of snake venom toxin, there are now>700 sequences of three-finger toxins (3FTxs) available, many of which are yet to be studied. While the function of 3FTxs are normally associated with neurotoxicity, increasingly more 3FTxs have been characterized to have pharmacological effects on cardiovascular systems. Here we focus on this family of snake venom toxins and their potential in developing therapeutics against cardiovascular diseases.
Collapse
Affiliation(s)
- R Manjunatha Kini
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 117558, Singapore; Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117600, Singapore
| | - Cho Yeow Koh
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 119228, Singapore.
| |
Collapse
|
10
|
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.
Collapse
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; , ,
| |
Collapse
|
11
|
Modahl CM, Mackessy SP. Venoms of Rear-Fanged Snakes: New Proteins and Novel Activities. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00279] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
12
|
Ferraz CR, Arrahman A, Xie C, Casewell NR, Lewis RJ, Kool J, Cardoso FC. Multifunctional Toxins in Snake Venoms and Therapeutic Implications: From Pain to Hemorrhage and Necrosis. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00218] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
|
13
|
Munawar A, Ali SA, Akrem A, Betzel C. Snake Venom Peptides: Tools of Biodiscovery. Toxins (Basel) 2018; 10:toxins10110474. [PMID: 30441876 PMCID: PMC6266942 DOI: 10.3390/toxins10110474] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 10/30/2018] [Accepted: 11/07/2018] [Indexed: 01/09/2023] Open
Abstract
Nature endowed snakes with a lethal secretion known as venom, which has been fine-tuned over millions of years of evolution. Snakes utilize venom to subdue their prey and to survive in their natural habitat. Venom is known to be a very poisonous mixture, consisting of a variety of molecules, such as carbohydrates, nucleosides, amino acids, lipids, proteins and peptides. Proteins and peptides are the major constituents of the dry weight of snake venoms and are of main interest for scientific investigations as well as for various pharmacological applications. Snake venoms contain enzymatic and non-enzymatic proteins and peptides, which are grouped into different families based on their structure and function. Members of a single family display significant similarities in their primary, secondary and tertiary structures, but in many cases have distinct pharmacological functions and different bioactivities. The functional specificity of peptides belonging to the same family can be attributed to subtle variations in their amino acid sequences. Currently, complementary tools and techniques are utilized to isolate and characterize the peptides, and study their potential applications as molecular probes, and possible templates for drug discovery and design investigations.
Collapse
Affiliation(s)
- Aisha Munawar
- Department of Chemistry, University of Engineering and Technology, Lahore 54890, Pakistan.
| | - Syed Abid Ali
- H.E. J. Research Institute of Chemistry, (ICCBS), University of Karachi, Karachi 75270, Pakistan.
| | - Ahmed Akrem
- Botany Division, Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan 60800, Pakistan.
| | - Christian Betzel
- Department of Chemistry, Institute of Biochemistry and Molecular Biology, University of Hamburg, 22607 Hamburg, Germany.
- Laboratory for Structural Biology of Infection and Inflammation, DESY, Build. 22a, Notkestr. 85, 22603 Hamburg, Germany.
| |
Collapse
|
14
|
Chapeaurouge A, Silva A, Carvalho P, McCleary RJR, Modahl CM, Perales J, Kini RM, Mackessy SP. Proteomic Deep Mining the Venom of the Red-Headed Krait, Bungarus flaviceps. Toxins (Basel) 2018; 10:E373. [PMID: 30217057 PMCID: PMC6162843 DOI: 10.3390/toxins10090373] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/28/2018] [Accepted: 09/01/2018] [Indexed: 01/20/2023] Open
Abstract
The use of -omics technologies allows for the characterization of snake venom composition at a fast rate and at high levels of detail. In the present study, we investigated the protein content of Red-headed Krait (Bungarus flaviceps) venom. This analysis revealed a high diversity of snake venom protein families, as evidenced by high-throughput mass spectrometric analysis. We found all six venom protein families previously reported in a transcriptome study of the venom gland of B. flaviceps, including phospholipases A₂ (PLA₂s), Kunitz-type serine proteinase inhibitors (KSPIs), three-finger toxins (3FTxs), cysteine-rich secretory proteins (CRISPs), snaclecs, and natriuretic peptides. A combined approach of automated database searches and de novo sequencing of tandem mass spectra, followed by sequence similarity searches, revealed the presence of 12 additional toxin families. De novo sequencing alone was able to identify 58 additional peptides, and this approach contributed significantly to the comprehensive description of the venom. Abundant protein families comprise 3FTxs (22.3%), KSPIs (19%), acetylcholinesterases (12.6%), PLA₂s (11.9%), venom endothelial growth factors (VEGFs, 8.4%), nucleotidases (4.3%), and C-type lectin-like proteins (snaclecs, 3.3%); an additional 11 toxin families are present at significantly lower concentrations, including complement depleting factors, a family not previously detected in Bungarus venoms. The utility of a multifaceted approach toward unraveling the proteome of snake venoms, employed here, allowed detection of even minor venom components. This more in-depth knowledge of the composition of B. flaviceps venom facilitates a better understanding of snake venom molecular evolution, in turn contributing to more effective treatment of krait bites.
Collapse
Affiliation(s)
- Alex Chapeaurouge
- Fundação Oswaldo Cruz-Ceará, Rua São José, 2º Pavimento, Precabura, Eusébio 61760-000, Brazil.
| | - Andreza Silva
- Laboratório de Toxinologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21045-900, Brazil.
| | - Paulo Carvalho
- Computational Mass Spectrometry& Proteomics Group, Carlos Chagas Institute, Fiocruz, Paraná 81350-010, Brazil.
| | - Ryan J R McCleary
- Department of Biology, Stetson University, 421 N. Woodland Blvd, DeLand, FL 32723, USA.
| | - Cassandra Marie Modahl
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore.
| | - Jonas Perales
- Laboratório de Toxinologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro 21045-900, Brazil.
| | - R Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore.
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, 501 20th St., CB 92, Greeley, CO 80639-0017, USA.
| |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
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: 44] [Impact Index Per Article: 7.3] [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.
Collapse
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.
| |
Collapse
|
17
|
Oyama E, Takahashi H, Ishii K. Effect of amino acids near the RGD sequence on binding activities between αIIbβ3 integrin and fibrinogen in the presence of RGD-containing synthetic peptides from elegantin and angustatin. Peptides 2017; 96:31-37. [PMID: 28887046 DOI: 10.1016/j.peptides.2017.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 09/01/2017] [Accepted: 09/03/2017] [Indexed: 10/18/2022]
Abstract
Elegantin and angustatin, which were isolated from the snake venoms of Protobothrops elegans and Dendroaspis angusticeps, markedly inhibit binding between platelet integrins and fibrinogen via the Arg-Gly-Asp (RGD) sequence. Angustatin, which is a three-finger toxin containing the RGD sequence, inhibits platelet aggregation almost ten times more strongly than disintegrin isolated from the venoms of Viperidae and Crotalidae. The RGD sequences of both polypeptides are located at the top of hairpin loops, and the composition of the RGD loop is very important for binding to integrin. We investigated the effects of synthetic RGD loop peptides from angustatin and elegantin on ADP- or collagen-induced platelet aggregation and αIIbβ3-fibrinogen binding. Synthetic angustatin (PRGDMP)-type peptides inhibited platelet aggregation more strongly than elegantin (ARGDDX)-type peptides. In particular, the cyclic angustatin peptide (CPRGDMPC) inhibited ADP- and collagen-induced platelet aggregation at least 10-50 times more strongly than the other peptides. The cyclic angustatin peptide (CPRGDMPC) was also the strongest inhibitor of binding between αIIbβ3 and fibrinogen, the IC50 of this peptide was approximately 2.58μM. Regarding the inhibition of binding between αIIbβ3 and fibrinogen, CPRGDMPC demonstrated a stronger inhibitory and more stable effect in the presence of Mg2+ than in the presence of Ca2+.
Collapse
Affiliation(s)
- Etsuko Oyama
- Department of Hyginic chemistry, Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose-shi, Tokyo 204-8588, Japan.
| | - Hidenobu Takahashi
- Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose-shi, Tokyo 204-8588, Japan
| | - Kazuyuki Ishii
- Department of Hyginic chemistry, Meiji Pharmaceutical University, 2-522-1, Noshio, Kiyose-shi, Tokyo 204-8588, Japan
| |
Collapse
|
18
|
Kessler P, Marchot P, Silva M, Servent D. The three-finger toxin fold: a multifunctional structural scaffold able to modulate cholinergic functions. J Neurochem 2017; 142 Suppl 2:7-18. [PMID: 28326549 DOI: 10.1111/jnc.13975] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/12/2017] [Accepted: 01/30/2017] [Indexed: 12/26/2022]
Abstract
Three-finger fold toxins are miniproteins frequently found in Elapidae snake venoms. This fold is characterized by three distinct loops rich in β-strands and emerging from a dense, globular core reticulated by four highly conserved disulfide bridges. The number and diversity of receptors, channels, and enzymes identified as targets of three-finger fold toxins is increasing continuously. Such manifold diversity highlights the specific adaptability of this fold for generating pleiotropic functions. Although this toxin superfamily disturbs many biological functions by interacting with a large diversity of molecular targets, the most significant target is the cholinergic system. By blocking the activity of the nicotinic and muscarinic acetylcholine receptors or by inhibiting the enzyme acetylcholinesterase, three-finger fold toxins interfere most drastically with neuromuscular junction functioning. Several of these toxins have become powerful pharmacological tools for studying the function and structure of their molecular targets. Most importantly, since dysfunction of these receptors/enzyme is involved in many diseases, exploiting the three-finger scaffold to create novel, highly specific therapeutic agents may represent a major future endeavor. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
Collapse
Affiliation(s)
- Pascal Kessler
- Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), IBITECS, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Pascale Marchot
- Aix-Marseille Université/Centre National de la Recherche Scientifique, Architecture et Fonction des Macromolécules Biologiques laboratory, Faculté des Sciences Campus Luminy, Marseille, France
| | - Marcela Silva
- Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), IBITECS, CEA, Université Paris-Saclay, Gif-sur-Yvette, France.,Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Denis Servent
- Service d'Ingénierie Moléculaire des Protéines (SIMOPRO), IBITECS, CEA, Université Paris-Saclay, Gif-sur-Yvette, France
| |
Collapse
|
19
|
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.
Collapse
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.
| |
Collapse
|
20
|
Chan YS, Cheung RCF, Xia L, Wong JH, Ng TB, Chan WY. Snake venom toxins: toxicity and medicinal applications. Appl Microbiol Biotechnol 2016; 100:6165-6181. [PMID: 27245678 DOI: 10.1007/s00253-016-7610-9] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 05/01/2016] [Accepted: 05/03/2016] [Indexed: 11/25/2022]
Abstract
Snake venoms are complex mixtures of small molecules and peptides/proteins, and most of them display certain kinds of bioactivities. They include neurotoxic, cytotoxic, cardiotoxic, myotoxic, and many different enzymatic activities. Snake envenomation is a significant health issue as millions of snakebites are reported annually. A large number of people are injured and die due to snake venom poisoning. However, several fatal snake venom toxins have found potential uses as diagnostic tools, therapeutic agent, or drug leads. In this review, different non-enzymatically active snake venom toxins which have potential therapeutic properties such as antitumor, antimicrobial, anticoagulating, and analgesic activities will be discussed.
Collapse
Affiliation(s)
- Yau Sang Chan
- State Key Laboratory of Respiratory Disease for Allergy, School of Medicine, Shenzhen University, Nanhai Ave 3688, 518060, Shenzhen, Guangdong, China
| | - Randy Chi Fai Cheung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Lixin Xia
- State Key Laboratory of Respiratory Disease for Allergy, School of Medicine, Shenzhen University, Nanhai Ave 3688, 518060, Shenzhen, Guangdong, China.
| | - Jack Ho Wong
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| | - Tzi Bun Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| | - Wai Yee Chan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| |
Collapse
|
21
|
Sanz-Soler R, Sanz L, Calvete JJ. Distribution ofRPTLNGenes Across Reptilia: Hypothesized Role for RPTLN in the Evolution of SVMPs. Integr Comp Biol 2016; 56:989-1003. [DOI: 10.1093/icb/icw031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
|
22
|
Hassan-Puttaswamy V, Adams DJ, Kini RM. A Distinct Functional Site in Ω-Neurotoxins: Novel Antagonists of Nicotinic Acetylcholine Receptors from Snake Venom. ACS Chem Biol 2015; 10:2805-15. [PMID: 26448325 DOI: 10.1021/acschembio.5b00492] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Snake venom α-neurotoxins from the three-finger toxin (3FTx) family are competitive antagonists with nanomolar affinity and high selectivity for nicotinic acetylcholine receptors (nAChR). Here, we report the characterization of a new group of competitive nAChR antagonists: Ω-neurotoxins. Although they belong to the 3FTx family, the characteristic functional residues of α-neurotoxins are not conserved. We evaluated the subtype specificity and structure-function relationships of Oh9-1, an Ω-neurotoxin from Ophiophagus hannah venom. Recombinant Oh9-1 showed reversible postsynaptic neurotoxicity in the micromolar range. Experiments with different nAChR subtypes expressed in Xenopus oocytes indicated Oh9-1 is selective for rat muscle type α1β1εδ (adult) and α1β1γδ (fetal) and rat neuronal α3β2 subtypes. However, Oh9-1 showed low or no affinity for other human and rat neuronal subtypes. Twelve individual alanine-scan mutants encompassing all three loops of Oh9-1 were evaluated for binding to α1β1εδ and α3β2 subtypes. Oh9-1's loop-II residues (M25, F27) were the most critical for interactions and formed the common binding core. Mutations at T23 and F26 caused a significant loss in activity at α1β1εδ receptors but had no effect on the interaction with the α3β2 subtype. Similarly, mutations at loop-II (H7, K22, H30) and -III (K45) of Oh9-1 had a distinctly different impact on its activity with these subtypes. Thus, Oh9-1 interacts with these nAChRs via distinct residues. Unlike α-neurotoxins, the tip of loop-II is not involved. We reveal a novel mode of interaction, where both sides of the β-strand of Oh9-1's loop-II interact with α1β1εδ, but only one side interacts with α3β2. Phylogenetic analysis revealed functional organization of the Ω-neurotoxins independent of α-neurotoxins. Thus, Ω-neurotoxin: Oh9-1 may be a new, structurally distinct class of 3FTxs that, like α-neurotoxins, antagonize nAChRs. However, Oh9-1 binds to the ACh binding pocket via a different set of functional residues.
Collapse
Affiliation(s)
| | - David J. Adams
- Health
Innovations Research Institute, RMIT University, Melbourne, Victoria 3083, Australia
| | - R. Manjunatha Kini
- Department
of Biological Sciences, National University of Singapore, Singapore 117543
| |
Collapse
|
23
|
Reeks TA, Fry BG, Alewood PF. Privileged frameworks from snake venom. Cell Mol Life Sci 2015; 72:1939-58. [PMID: 25693678 PMCID: PMC11113608 DOI: 10.1007/s00018-015-1844-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 01/22/2015] [Accepted: 01/26/2015] [Indexed: 11/25/2022]
Abstract
Venom as a form of chemical prey capture is a key innovation that has underpinned the explosive radiation of the advanced snakes (Caenophidia). Small venom proteins are often rich in disulfide bonds thus facilitating stable molecular scaffolds that present key functional residues on the protein surface. New toxin types are initially developed through the venom gland over-expression of normal body proteins, their subsequent gene duplication and diversification that leads to neofunctionalisation as random mutations modify their structure and function. This process has led to preferentially selected (privileged) cysteine-rich scaffolds that enable the snake to build arrays of toxins many of which may lead to therapeutic products and research tools. This review focuses on cysteine-rich small proteins and peptides found in snake venoms spanning natriuretic peptides to phospholipase enzymes, while highlighting their three-dimensional structures and biological functions as well as their potential as therapeutic agents or research tools.
Collapse
Affiliation(s)
- T. A. Reeks
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072 Australia
| | - B. G. Fry
- Venom Evolution Lab, School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072 Australia
| | - P. F. Alewood
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072 Australia
| |
Collapse
|
24
|
Oyama E, Takahashi H. Purification and characterization of two platelet-aggregation inhibitors, named angustatin and H-toxin TA2, from the venom of Dendroaspis angusticeps. Toxicon 2015; 93:61-7. [DOI: 10.1016/j.toxicon.2014.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 10/23/2014] [Accepted: 11/04/2014] [Indexed: 10/24/2022]
|
25
|
Polypharmacology profiles and phylogenetic analysis of three-finger toxins from mamba venom: Case of aminergic toxins. Biochimie 2014; 103:109-17. [DOI: 10.1016/j.biochi.2014.04.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/22/2014] [Indexed: 12/21/2022]
|
26
|
Wilburn DB, Bowen KE, Doty KA, Arumugam S, Lane AN, Feldhoff PW, Feldhoff RC. Structural insights into the evolution of a sexy protein: novel topology and restricted backbone flexibility in a hypervariable pheromone from the red-legged salamander, Plethodon shermani. PLoS One 2014; 9:e96975. [PMID: 24849290 PMCID: PMC4029566 DOI: 10.1371/journal.pone.0096975] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 04/15/2014] [Indexed: 11/18/2022] Open
Abstract
In response to pervasive sexual selection, protein sex pheromones often display rapid mutation and accelerated evolution of corresponding gene sequences. For proteins, the general dogma is that structure is maintained even as sequence or function may rapidly change. This phenomenon is well exemplified by the three-finger protein (TFP) superfamily: a diverse class of vertebrate proteins co-opted for many biological functions - such as components of snake venoms, regulators of the complement system, and coordinators of amphibian limb regeneration. All of the >200 structurally characterized TFPs adopt the namesake "three-finger" topology. In male red-legged salamanders, the TFP pheromone Plethodontid Modulating Factor (PMF) is a hypervariable protein such that, through extensive gene duplication and pervasive sexual selection, individual male salamanders express more than 30 unique isoforms. However, it remained unclear how this accelerated evolution affected the protein structure of PMF. Using LC/MS-MS and multidimensional NMR, we report the 3D structure of the most abundant PMF isoform, PMF-G. The high resolution structural ensemble revealed a highly modified TFP structure, including a unique disulfide bonding pattern and loss of secondary structure, that define a novel protein topology with greater backbone flexibility in the third peptide finger. Sequence comparison, models of molecular evolution, and homology modeling together support that this flexible third finger is the most rapidly evolving segment of PMF. Combined with PMF sequence hypervariability, this structural flexibility may enhance the plasticity of PMF as a chemical signal by permitting potentially thousands of structural conformers. We propose that the flexible third finger plays a critical role in PMF:receptor interactions. As female receptors co-evolve, this flexibility may allow PMF to still bind its receptor(s) without the immediate need for complementary mutations. Consequently, this unique adaptation may establish new paradigms for how receptor:ligand pairs co-evolve, in particular with respect to sexual conflict.
Collapse
Affiliation(s)
- Damien B. Wilburn
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
| | - Kathleen E. Bowen
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
| | - Kari A. Doty
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
| | - Sengodagounder Arumugam
- J.G. Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Andrew N. Lane
- J.G. Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Pamela W. Feldhoff
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
| | - Richard C. Feldhoff
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail:
| |
Collapse
|
27
|
Three-fingered RAVERs: Rapid Accumulation of Variations in Exposed Residues of snake venom toxins. Toxins (Basel) 2013; 5:2172-208. [PMID: 24253238 PMCID: PMC3847720 DOI: 10.3390/toxins5112172] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 11/08/2013] [Accepted: 11/11/2013] [Indexed: 12/21/2022] Open
Abstract
Three-finger toxins (3FTx) represent one of the most abundantly secreted and potently toxic components of colubrid (Colubridae), elapid (Elapidae) and psammophid (Psammophiinae subfamily of the Lamprophidae) snake venom arsenal. Despite their conserved structural similarity, they perform a diversity of biological functions. Although they are theorised to undergo adaptive evolution, the underlying diversification mechanisms remain elusive. Here, we report the molecular evolution of different 3FTx functional forms and show that positively selected point mutations have driven the rapid evolution and diversification of 3FTx. These diversification events not only correlate with the evolution of advanced venom delivery systems (VDS) in Caenophidia, but in particular the explosive diversification of the clade subsequent to the evolution of a high pressure, hollow-fanged VDS in elapids, highlighting the significant role of these toxins in the evolution of advanced snakes. We show that Type I, II and III α-neurotoxins have evolved with extreme rapidity under the influence of positive selection. We also show that novel Oxyuranus/Pseudonaja Type II forms lacking the apotypic loop-2 stabilising cysteine doublet characteristic of Type II forms are not phylogenetically basal in relation to other Type IIs as previously thought, but are the result of secondary loss of these apotypic cysteines on at least three separate occasions. Not all 3FTxs have evolved rapidly: κ-neurotoxins, which form non-covalently associated heterodimers, have experienced a relatively weaker influence of diversifying selection; while cytotoxic 3FTx, with their functional sites, dispersed over 40% of the molecular surface, have been extremely constrained by negative selection. We show that the a previous theory of 3FTx molecular evolution (termed ASSET) is evolutionarily implausible and cannot account for the considerable variation observed in very short segments of 3FTx. Instead, we propose a theory of Rapid Accumulation of Variations in Exposed Residues (RAVER) to illustrate the significance of point mutations, guided by focal mutagenesis and positive selection in the evolution and diversification of 3FTx.
Collapse
|
28
|
Cheng CH, Chen YC, Shiu JH, Chang YT, Chang YS, Huang CH, Chen CY, Chuang WJ. Dynamics and functional differences between dendroaspin and rhodostomin: insights into protein scaffolds in integrin recognition. Protein Sci 2012; 21:1872-84. [PMID: 23033223 DOI: 10.1002/pro.2169] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 09/19/2012] [Indexed: 12/21/2022]
Abstract
Dendroaspin (Den) and rhodostomin (Rho) are snake venom proteins containing a PRGDMP motif. Although Den and Rho have different 3D structures, they are highly potent integrin inhibitors. To study their structure, function, and dynamics relationships, we expressed Den and Rho in Pichia pastoris. The recombinant Den and Rho inhibited platelet aggregation with the K(I) values of 149.8 and 83.2 nM. Cell adhesion analysis showed that Den was 3.7 times less active than Rho when inhibiting the integrin αIIbβ3 and 2.5 times less active when inhibiting the integrin αvβ3. In contrast, Den and Rho were similarly active when inhibiting the integrin α5β1 with the IC₅₀ values of 239.8 and 256.8 nM. NMR analysis showed that recombinant Den and Rho have different 3D conformations for their arginyl-glycyl-aspartic acid (RGD) motif. However, the comparison with Rho showed that the docking of Den into integrin αvβ3 resulted in a similar number of contacts. Analysis of the dynamic properties of the RGD loop in Den and Rho showed that they also had different dynamic properties. These results demonstrate that protein scaffolds affect the function, structure, and dynamics of their RGD motif.
Collapse
Affiliation(s)
- Chun-Ho Cheng
- Department of Biochemistry and Institute of Basic Medical Sciences, National Cheng Kung University College of Medicine, Tainan 701, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Girish VM, Kumar S, Joseph L, Jobichen C, Kini RM, Sivaraman J. Identification and structural characterization of a new three-finger toxin hemachatoxin from Hemachatus haemachatus venom. PLoS One 2012; 7:e48112. [PMID: 23144733 PMCID: PMC3483290 DOI: 10.1371/journal.pone.0048112] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Accepted: 09/19/2012] [Indexed: 01/26/2023] Open
Abstract
Snake venoms are rich sources of biologically active proteins and polypeptides. Three-finger toxins are non-enzymatic proteins present in elapid (cobras, kraits, mambas and sea snakes) and colubrid venoms. These proteins contain four conserved disulfide bonds in the core to maintain the three-finger folds. Although all three-finger toxins have similar fold, their biological activities are different. A new three-finger toxin (hemachatoxin) was isolated from Hemachatus haemachatus (Ringhals cobra) venom. Its amino acid sequence was elucidated, and crystal structure was determined at 2.43 Å resolution. The overall fold is similar to other three-finger toxins. The structure and sequence analysis revealed that the fold is maintained by four highly conserved disulfide bonds. It exhibited highest similarity to particularly P-type cardiotoxins that are known to associate and perturb the membrane surface with their lipid binding sites. Also, the increased B value of hemachotoxin loop II suggests that loop II is flexible and may remain flexible until its interaction with membrane phospholipids. Based on the analysis, we predict hemachatoxin to be cardiotoxic/cytotoxic and our future experiments will be directed to characterize the activity of hemachatoxin.
Collapse
Affiliation(s)
| | - Sundramurthy Kumar
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Lissa Joseph
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Chacko Jobichen
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - R. Manjunatha Kini
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia, United States of America
- * E-mail: (RMK); (JS)
| | - J. Sivaraman
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
- * E-mail: (RMK); (JS)
| |
Collapse
|
30
|
Abstract
Venoms and toxins are of significant interest due to their ability to cause a wide range of pathophysiological conditions that can potentially result in death. Despite their wide distribution among plants and animals, the biochemical pathways associated with these pathogenic agents remain largely unexplored. Impoverished and underdeveloped regions appear especially susceptible to increased incidence and severity due to poor socioeconomic conditions and lack of appropriate medical treatment infrastructure. To facilitate better management and treatment of envenomation victims, it is essential that the biochemical mechanisms of their action be elucidated. This review aims to characterize downstream envenomation mechanisms by addressing the major neuro-, cardio-, and hemotoxins as well as ion-channel toxins. Because of their use in folk and traditional medicine, the biochemistry behind venom therapy and possible implications on conventional medicine will also be addressed.
Collapse
|
31
|
Näreoja K, Näsman J. Selective targeting of G-protein-coupled receptor subtypes with venom peptides. Acta Physiol (Oxf) 2012; 204:186-201. [PMID: 21481193 DOI: 10.1111/j.1748-1716.2011.02305.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The G-protein-coupled receptor (GPCR) family is one of the largest gene superfamilies with approx. 370 members responding to endogenous ligands in humans and a roughly equal amount of receptors sensitive to external stimuli from the surrounding. A number of receptors from this superfamily are well recognized targets for medical treatment of various disease conditions, whereas for many others the potential medical benefit of interference is still obscure. A general problem associated with GPCR research and therapeutics is the insufficient specificity of available ligands to differentiate between closely homologous receptor subtypes. In this context, venom peptides could make a significant contribution to the development of more specific drugs. Venoms from certain animals specialized in biochemical hunting contain a mixture of molecules that are directed towards a variety of membrane proteins. Peptide toxins isolated from these mixtures usually exhibit high specificity for their targets. Muscarinic toxins found from mamba snakes attracted much attention during the 1990s. These are 65-66 amino acid long peptides with a structural three-finger folding similar to the α-neurotoxins and they target the muscarinic acetylcholine receptors in a subtype-selective manner. Recently, several members of the three-finger toxins from mamba snakes as well as conotoxins from marine cone snails have been shown to selectively interact with subtypes of adrenergic receptors. In this review, we will discuss the GPCR-directed peptide toxins found from different venoms and how some of these can be useful in exploring specific roles of receptor subtypes.
Collapse
Affiliation(s)
- K Näreoja
- Department of Biosciences, Biochemistry, Åbo Akademi University, Turku, Finland
| | | |
Collapse
|
32
|
Abstract
Exogenous factors isolated from venoms of snakes and saliva of haematophagous animals that affect thrombosis and haemostasis have contributed significantly to the development of diagnostic agents, research tools and life-saving drugs. Here, I discuss recent advances in the discovery, structural and functional characterisation, and mechanism of action of new procoagulant and anti-haemostatic proteins. In nature, these factors have evolved to target crucial 'bottlenecks' in the coagulation cascade and platelet aggregation. Several simple protein scaffolds are used to target a wide variety of target proteins and receptors exhibiting functional divergence. Different protein scaffolds have also evolved to target identical, physiologically relevant key enzymes or receptors exhibiting functional convergence. At times, exogenous factors bind to the same target protein, but at distinct sites, to differentially attenuate their functions exhibiting mechanistic divergence within the same family of proteins. The structure-function relationships of these factors are subtle and complicated but represent an exciting challenge. These studies provide ample opportunities to design highly specific and precise ligands to achieve desired biological target function. Although only a small number of them have been characterised to date, the molecular and mechanical diversities of these exogenous factors and their contributions to understanding molecular and cellular events in thrombosis and haemostasis as well as developing diagnostic and research tools and therapeutic agents, is outstanding. Based on the current status, I have attempted to identify future potential and prospects in this area of research.
Collapse
Affiliation(s)
- R M Kini
- Protein Science Laboratory, Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore.
| |
Collapse
|
33
|
Sajevic T, Leonardi A, Križaj I. Haemostatically active proteins in snake venoms. Toxicon 2011; 57:627-45. [PMID: 21277886 DOI: 10.1016/j.toxicon.2011.01.006] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 01/06/2011] [Accepted: 01/07/2011] [Indexed: 11/16/2022]
Abstract
Snake venom proteins that affect the haemostatic system can cause (a) lowering of blood coagulability, (b) damage to blood vessels, resulting in bleeding, (c) secondary effects of bleeding, e.g. hypovolaemic shock and organ damage, and (d) thrombosis. These proteins may, or may not, be enzymes. We review the data on the most relevant haemostatically active proteinases, phospholipases A₂, L-amino acid oxidases and 5'-nucleotidases from snake venoms. We also survey the non-enzymatic effectors of haemostasis from snake venoms--disintegrins, C-type lectins and three-finger toxins. Medical applications have already been found for some of these snake venom proteins. We describe those that have already been approved as drugs to treat haemostatic disorders or are being used to diagnose such health problems. No clinical applications, however, currently exist for the majority of snake venom proteins acting on haemostasis. We conclude with the most promising potential uses in this respect.
Collapse
Affiliation(s)
- Tamara Sajevic
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| | | | | |
Collapse
|
34
|
Kini RM, Doley R. Structure, function and evolution of three-finger toxins: mini proteins with multiple targets. Toxicon 2010; 56:855-67. [PMID: 20670641 DOI: 10.1016/j.toxicon.2010.07.010] [Citation(s) in RCA: 262] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Accepted: 07/19/2010] [Indexed: 12/15/2022]
Abstract
Snake venoms are complex mixtures of pharmacologically active peptides and proteins. These protein toxins belong to a small number of superfamilies of proteins. Three-finger toxins belong to a superfamily of non-enzymatic proteins found in all families of snakes. They have a common structure of three beta-stranded loops extending from a central core containing all four conserved disulphide bonds. Despite the common scaffold, they bind to different receptors/acceptors and exhibit a wide variety of biological effects. Thus, the structure-function relationships of this group of toxins are complicated and challenging. Studies have shown that the functional sites in these 'sibling' toxins are located on various segments of the molecular surface. Targeting to a wide variety of receptors and ion channels and hence distinct functions in this group of mini proteins is achieved through a combination of accelerated rate of exchange of segments as well as point mutations in exons. In this review, we describe the structural and functional diversity, structure-function relationships and evolution of this group of snake venom toxins.
Collapse
Affiliation(s)
- R Manjunatha Kini
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 117543, Singapore.
| | | |
Collapse
|
35
|
Koivula K, Rondinelli S, Näsman J. The three-finger toxin MTalpha is a selective alpha(2B)-adrenoceptor antagonist. Toxicon 2010; 56:440-7. [PMID: 20466015 DOI: 10.1016/j.toxicon.2010.05.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 04/14/2010] [Accepted: 05/04/2010] [Indexed: 12/16/2022]
Abstract
Muscarinic toxins (MTs) are three-finger folded peptides isolated from mamba snake venoms. In this report we describe a selective antagonistic interaction of MTalpha with the human alpha(2B)-adrenoceptor. In a functional assay, measuring the alpha(2B)-adrenoceptor-induced increase in intracellular [Ca(2+)], we found that both venomous MTalpha and synthetic MTalpha inhibited the response in a concentration-dependent way. MTalpha did not affect the responses of alpha(2A)-, alpha(2C)-, alpha(1A)- or alpha(1B)-adrenoceptors. To further explore the binding of MTalpha to the alpha(2B)-adrenoceptor, we performed ligand binding experiments on Sf9 cell homogenates with [(3)H]RX821002 as reporter ligand. MTalpha bound to the receptor rather slowly requiring about 60 min to reach equilibrium. In equilibrium binding experiments, MTalpha displaced the radioligand with an IC(50) of 3.2 nM, but was not able to displace all bound radioligand. Using a saturation binding protocol, we found that MTalpha suppressed the maximum binding without any greater impact on the affinity of the radioligand, indicating a non-competitive mode of inhibition. The toxin bound reversibly to alpha(2B)-adrenoceptor, but extensive washing was needed for full recovery of binding sites at high toxin concentrations. Surprisingly, MTalpha did not affect [(3)H]-N-methylscopolamine binding to the muscarinic receptor subtypes at concentrations found to fully block alpha(2B)-adrenoceptors, showing that the toxin is a more potent antagonist for the alpha(2B)-adrenoceptor than for muscarinic receptors. These findings should open up new views in terms of selective adrenoceptor drug design as well as in elucidation of alpha(2)-adrenoceptor physiology.
Collapse
Affiliation(s)
- Katja Koivula
- Department of Biochemistry and Pharmacy, Abo Akademi University, Tykistökatu 6, FIN-20520 Turku, Finland
| | | | | |
Collapse
|
36
|
Siang AS, Doley R, Vonk FJ, Kini RM. Transcriptomic analysis of the venom gland of the red-headed krait (Bungarus flaviceps) using expressed sequence tags. BMC Mol Biol 2010; 11:24. [PMID: 20350308 PMCID: PMC2861064 DOI: 10.1186/1471-2199-11-24] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 03/29/2010] [Indexed: 03/10/2023] Open
Abstract
Background The Red-headed krait (Bungarus flaviceps, Squamata: Serpentes: Elapidae) is a medically important venomous snake that inhabits South-East Asia. Although the venoms of most species of the snake genus Bungarus have been well characterized, a detailed compositional analysis of B. flaviceps is currently lacking. Results Here, we have sequenced 845 expressed sequence tags (ESTs) from the venom gland of a B. flaviceps. Of the transcripts, 74.8% were putative toxins; 20.6% were cellular; and 4.6% were unknown. The main venom protein families identified were three-finger toxins (3FTxs), Kunitz-type serine protease inhibitors (including chain B of β-bungarotoxin), phospholipase A2 (including chain A of β-bungarotoxin), natriuretic peptide (NP), CRISPs, and C-type lectin. Conclusion The 3FTxs were found to be the major component of the venom (39%). We found eight groups of unique 3FTxs and most of them were different from the well-characterized 3FTxs. We found three groups of Kunitz-type serine protease inhibitors (SPIs); one group was comparable to the classical SPIs and the other two groups to chain B of β-bungarotoxins (with or without the extra cysteine) based on sequence identity. The latter group may be functional equivalents of dendrotoxins in Bungarus venoms. The natriuretic peptide (NP) found is the first NP for any Asian elapid, and distantly related to Australian elapid NPs. Our study identifies several unique toxins in B. flaviceps venom, which may help in understanding the evolution of venom toxins and the pathophysiological symptoms induced after envenomation.
Collapse
Affiliation(s)
- Ang Swee Siang
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117546, Singapore
| | | | | | | |
Collapse
|
37
|
Roy A, Zhou X, Chong MZ, D'hoedt D, Foo CS, Rajagopalan N, Nirthanan S, Bertrand D, Sivaraman J, Kini RM. Structural and functional characterization of a novel homodimeric three-finger neurotoxin from the venom of Ophiophagus hannah (king cobra). J Biol Chem 2010; 285:8302-15. [PMID: 20071329 DOI: 10.1074/jbc.m109.074161] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Snake venoms are a mixture of pharmacologically active proteins and polypeptides that have led to the development of molecular probes and therapeutic agents. Here, we describe the structural and functional characterization of a novel neurotoxin, haditoxin, from the venom of Ophiophagus hannah (King cobra). Haditoxin exhibited novel pharmacology with antagonism toward muscle (alphabetagammadelta) and neuronal (alpha(7), alpha(3)beta(2), and alpha(4)beta(2)) nicotinic acetylcholine receptors (nAChRs) with highest affinity for alpha(7)-nAChRs. The high resolution (1.5 A) crystal structure revealed haditoxin to be a homodimer, like kappa-neurotoxins, which target neuronal alpha(3)beta(2)- and alpha(4)beta(2)-nAChRs. Interestingly however, the monomeric subunits of haditoxin were composed of a three-finger protein fold typical of curaremimetic short-chain alpha-neurotoxins. Biochemical studies confirmed that it existed as a non-covalent dimer species in solution. Its structural similarity to short-chain alpha-neurotoxins and kappa-neurotoxins notwithstanding, haditoxin exhibited unique blockade of alpha(7)-nAChRs (IC(50) 180 nm), which is recognized by neither short-chain alpha-neurotoxins nor kappa-neurotoxins. This is the first report of a dimeric short-chain alpha-neurotoxin interacting with neuronal alpha(7)-nAChRs as well as the first homodimeric three-finger toxin to interact with muscle nAChRs.
Collapse
Affiliation(s)
- Amrita Roy
- Department of Biological Sciences, National University of Singapore, Singapore
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Fry BG, Roelants K, Champagne DE, Scheib H, Tyndall JD, King GF, Nevalainen TJ, Norman JA, Lewis RJ, Norton RS, Renjifo C, de la Vega RCR. The Toxicogenomic Multiverse: Convergent Recruitment of Proteins Into Animal Venoms. Annu Rev Genomics Hum Genet 2009; 10:483-511. [DOI: 10.1146/annurev.genom.9.081307.164356] [Citation(s) in RCA: 587] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Throughout evolution, numerous proteins have been convergently recruited into the venoms of various animals, including centipedes, cephalopods, cone snails, fish, insects (several independent venom systems), platypus, scorpions, shrews, spiders, toxicoferan reptiles (lizards and snakes), and sea anemones. The protein scaffolds utilized convergently have included AVIT/colipase/prokineticin, CAP, chitinase, cystatin, defensins, hyaluronidase, Kunitz, lectin, lipocalin, natriuretic peptide, peptidase S1, phospholipase A2, sphingomyelinase D, and SPRY. Many of these same venom protein types have also been convergently recruited for use in the hematophagous gland secretions of invertebrates (e.g., fleas, leeches, kissing bugs, mosquitoes, and ticks) and vertebrates (e.g., vampire bats). Here, we discuss a number of overarching structural, functional, and evolutionary generalities of the protein families from which these toxins have been frequently recruited and propose a revised and expanded working definition for venom. Given the large number of striking similarities between the protein compositions of conventional venoms and hematophagous secretions, we argue that the latter should also fall under the same definition.
Collapse
Affiliation(s)
- Bryan G. Fry
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Melbourne 3010 Australia
| | - Kim Roelants
- Unit of Ecology and Systematics, Vrije Universiteit Brussels, 1050 Brussels, Belgium
| | - Donald E. Champagne
- Department of Entomology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia 30602
| | | | - Joel D.A. Tyndall
- National School of Pharmacy, University of Otago, Dunedin 9054, New Zealand
| | - Glenn F. King
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia
| | | | - Janette A. Norman
- Sciences Department, Museum Victoria, Melbourne, Victoria 3001, Australia
| | - Richard J. Lewis
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Raymond S. Norton
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3050, Victoria, Australia
| | - Camila Renjifo
- Department of Physiological Sciences, Faculty of Medicine, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Ricardo C. Rodríguez de la Vega
- Structural and Computational Biology/Gene Expression Units, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| |
Collapse
|
39
|
|
40
|
Doley R, Mackessy SP, Kini RM. Role of accelerated segment switch in exons to alter targeting (ASSET) in the molecular evolution of snake venom proteins. BMC Evol Biol 2009; 9:146. [PMID: 19563684 PMCID: PMC2711939 DOI: 10.1186/1471-2148-9-146] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Accepted: 06/30/2009] [Indexed: 11/19/2022] Open
Abstract
Background Snake venom toxins evolve more rapidly than other proteins through accelerated changes in the protein coding regions. Previously we have shown that accelerated segment switch in exons to alter targeting (ASSET) might play an important role in its functional evolution of viperid three-finger toxins. In this phenomenon, short sequences in exons are radically changed to unrelated sequences and hence affect the folding and functional properties of the toxins. Results Here we analyzed other snake venom protein families to elucidate the role of ASSET in their functional evolution. ASSET appears to be involved in the functional evolution of three-finger toxins to a greater extent than in several other venom protein families. ASSET leads to replacement of some of the critical amino acid residues that affect the biological function in three-finger toxins as well as change the conformation of the loop that is involved in binding to specific target sites. Conclusion ASSET could lead to novel functions in snake venom proteins. Among snake venom serine proteases, ASSET contributes to changes in three surface segments. One of these segments near the substrate binding region is known to affect substrate specificity, and its exchange may have significant implications for differences in isoform catalytic activity on specific target protein substrates. ASSET therefore plays an important role in functional diversification of snake venom proteins, in addition to accelerated point mutations in the protein coding regions. Accelerated point mutations lead to fine-tuning of target specificity, whereas ASSET leads to large-scale replacement of multiple functionally important residues, resulting in change or gain of functions.
Collapse
Affiliation(s)
- Robin Doley
- Department of Biological Sciences, National University of Singapore, Singapore.
| | | | | |
Collapse
|
41
|
Fry BG, Vidal N, van der Weerd L, Kochva E, Renjifo C. Evolution and diversification of the Toxicofera reptile venom system. J Proteomics 2009; 72:127-36. [DOI: 10.1016/j.jprot.2009.01.009] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Accepted: 01/12/2009] [Indexed: 11/25/2022]
|
42
|
Huang TF, Niewiarowski S. Disintegrins: The Naturally-Occurring Antagonists of Platelet Fibrinogen Receptor. ACTA ACUST UNITED AC 2008. [DOI: 10.3109/15569549409089964] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
43
|
Doley R, Pahari S, Mackessy SP, Kini RM. Accelerated exchange of exon segments in Viperid three-finger toxin genes (Sistrurus catenatus edwardsii; Desert Massasauga). BMC Evol Biol 2008; 8:196. [PMID: 18606022 PMCID: PMC2474615 DOI: 10.1186/1471-2148-8-196] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 07/08/2008] [Indexed: 11/10/2022] Open
Abstract
Background Snake venoms consist primarily of proteins and peptides showing a myriad of potent biological activities which have been shaped by both adaptive and neutral selective forces. Venom proteins are encoded by multigene families that have evolved through a process of gene duplication followed by accelerated evolution in the protein coding region. Results Here we report five gene structures of three-finger toxins from a viperid snake, Sistrurus catenatus edwardsii. These toxin genes are structured similarly to elapid and hydrophiid three-finger toxin genes, with two introns and three exons. Both introns and exons show distinct patterns of segmentation, and the insertion/deletion of segments may define their evolutionary history. The segments in introns, when present, are highly similar to their corresponding segments in other members of the gene family. In contrast, some segments in the exons show high similarity, while others are often distinctly different among corresponding regions of the isoforms. Conclusion Ordered, conserved exon structure strongly suggests that segments in corresponding regions in exons have been exchanged with distinctly different ones during the evolution of these genes. Such a "switching" of segments in exons may result in drastically altering the molecular surface topology and charge, and hence the molecular targets of these three-finger toxins. Thus the phenomenon of accelerated segment switch in exons to alter targeting (ASSET) may play an important role in the evolution of three-finger toxins, resulting in a family of toxins with a highly conserved structural fold but widely varying biological activities.
Collapse
Affiliation(s)
- Robin Doley
- Protein Science Laboratory, Department of Biological Sciences, National University of Singapore, 117543, Singapore.
| | | | | | | |
Collapse
|
44
|
Rajagopalan N, Pung YF, Zhu YZ, Wong PTH, Kumar PP, Kini RM. Beta-cardiotoxin: a new three-finger toxin from Ophiophagus hannah (king cobra) venom with beta-blocker activity. FASEB J 2007; 21:3685-95. [PMID: 17616557 DOI: 10.1096/fj.07-8658com] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Snake venoms have provided a number of novel ligands with therapeutic potential. We have constructed a partial cDNA library from the mRNA of Ophiophagus hannah (king cobra) venom gland tissue and identified five new genes encoding proteins belonging to the three-finger toxin family of snake venom proteins. We have isolated and characterized one of these beta-sheet containing proteins with a mass of 7012.43 +/- 0.91 Da from the venom. The protein was nonlethal up to a dose of 10 mg/kg when injected intraperitoneally into Swiss albino mice. However, it induces labored breathing and death at a dose of 100 mg/kg. It does not show any hemolytic or anticoagulant activity. It caused a dose-dependent decrease of heart rate in vivo (anesthetized Sprague-Dawley rats) and also ex vivo (Langendorff isolated rat heart). This is in contrast to classical cardiotoxins from snake venom that increase the heart rate in animals. Radioligand displacement studies showed that this protein targets beta-adrenergic receptors with a binding affinity (Ki) of 5.3 and 2.3 microM toward beta1 and beta2 subtypes, respectively, to bring about its effect, and hence, it was named as beta-cardiotoxin. This is the first report of a natural exogenous beta-blocker.
Collapse
Affiliation(s)
- Nandhakishore Rajagopalan
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Science Dr. 4, Singapore 117543
| | | | | | | | | | | |
Collapse
|
45
|
Aota S, Yamada KM. Fibronectin and cell adhesion: specificity of integrin-ligand interaction. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 70:1-21. [PMID: 8638481 DOI: 10.1002/9780470123164.ch1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- S Aota
- Laboratory of Developmental Biology, National Institute of Dental Research, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | |
Collapse
|
46
|
Oyama E, Takahashi H. Distribution of low molecular weight platelet aggregation inhibitors from snake venoms. Toxicon 2006; 49:293-8. [PMID: 17141819 DOI: 10.1016/j.toxicon.2006.09.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Accepted: 09/20/2006] [Indexed: 10/24/2022]
Abstract
An assay of platelet aggregation inhibitors measured by the turbidimeter using Aggregometer PAM 8C (Mebanix) was performed after each crude snake venom (57 species) was subjected to ultrafiltration using MILLIPORE UFP 1 LGC. The snake venoms of Viperidae (three species), Elapidae (11 species), and Hydrophiidae (two species) inhibited ADP-induced rabbit platelet aggregation. In particular, six venoms of Bitis gabonica, Pseudocerastes persicus, Dendroaspis angusticeps, D. polylepis, Ophiophagus hannah, and N. nigricollis crawshawii strongly inhibited platelet aggregation. Furthermore, adenosine was identified from Bitis gabonica venom using HPLC and FAB/MS analysis.
Collapse
Affiliation(s)
- Etsuko Oyama
- Department of Hygenic Chemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
| | | |
Collapse
|
47
|
Abstract
Over the last several decades, research on snake venom toxins has provided not only new tools to decipher molecular details of various physiological processes, but also inspiration to design and develop a number of therapeutic agents. Blood circulation, particularly thrombosis and haemostasis, is one of the major targets of several snake venom proteins. Among them, anticoagulant proteins have contributed to our understanding of molecular mechanisms of blood coagulation and have provided potential new leads for the development of drugs to treat or to prevent unwanted clot formation. Some of these anticoagulants exhibit various enzymatic activities whereas others do not. They interfere in normal blood coagulation by different mechanisms. Although significant progress has been made in understanding the structure-function relationships and the mechanisms of some of these anticoagulants, there are still a number of questions to be answered as more new anticoagulants are being discovered. Such studies contribute to our fight against unwanted clot formation, which leads to death and debilitation in cardiac arrest and stroke in patients with cardiovascular and cerebrovascular diseases, arteriosclerosis and hypertension. This review describes the details of the structure, mechanism and structure-function relationships of anticoagulant proteins from snake venoms.
Collapse
Affiliation(s)
- R Manjunatha Kini
- Protein Science Laboratory, Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore.
| |
Collapse
|
48
|
Pawlak J, Mackessy SP, Fry BG, Bhatia M, Mourier G, Fruchart-Gaillard C, Servent D, Ménez R, Stura E, Ménez A, Kini RM. Denmotoxin, a three-finger toxin from the colubrid snake Boiga dendrophila (Mangrove Catsnake) with bird-specific activity. J Biol Chem 2006; 281:29030-41. [PMID: 16864572 DOI: 10.1074/jbc.m605850200] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Boiga dendrophila (mangrove catsnake) is a colubrid snake that lives in Southeast Asian lowland rainforests and mangrove swamps and that preys primarily on birds. We have isolated, purified, and sequenced a novel toxin from its venom, which we named denmotoxin. It is a monomeric polypeptide of 77 amino acid residues with five disulfide bridges. In organ bath experiments, it displayed potent postsynaptic neuromuscular activity and irreversibly inhibited indirectly stimulated twitches in chick biventer cervicis nerve-muscle preparations. In contrast, it induced much smaller and readily reversible inhibition of electrically induced twitches in mouse hemidiaphragm nerve-muscle preparations. More precisely, the chick muscle alpha(1)betagammadelta-nicotinic acetylcholine receptor was 100-fold more susceptible compared with the mouse receptor. These data indicate that denmotoxin has a bird-specific postsynaptic activity. We chemically synthesized denmotoxin, crystallized it, and solved its crystal structure at 1.9 A by the molecular replacement method. The toxin structure adopts a non-conventional three-finger fold with an additional (fifth) disulfide bond in the first loop and seven additional residues at its N terminus, which is blocked by a pyroglutamic acid residue. This is the first crystal structure of a three-finger toxin from colubrid snake venom and the first fully characterized bird-specific toxin. Denmotoxin illustrates the relationship between toxin specificity and the primary prey type that constitutes the snake's diet.
Collapse
Affiliation(s)
- Joanna Pawlak
- Department of Biological Sciences, Faculty of Science, National University of Singapore
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Francischetti IMB, My Pham V, Mans BJ, Andersen JF, Mather TN, Lane RS, Ribeiro JMC. The transcriptome of the salivary glands of the female western black-legged tick Ixodes pacificus (Acari: Ixodidae). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2005; 35:1142-61. [PMID: 16102420 PMCID: PMC2887698 DOI: 10.1016/j.ibmb.2005.05.007] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Revised: 05/19/2005] [Accepted: 05/20/2005] [Indexed: 05/04/2023]
Abstract
Sequencing of an Ixodes pacificus salivary gland cDNA library yielded 1068 sequences with an average undetermined nucleotide of 1.9% and an average length of 487 base pairs. Assembly of the expressed sequence tags yielded 557 contigs, 138 of which appear to code for secreted peptides or proteins based on translation of a putative signal peptide. Based on the BLASTX similarity of these contigs to 66 matches of Ixodes scapularis peptide sequences, only 58% sequence identity was found, indicating a rapid divergence of salivary proteins as observed previously for mosquito and triatomine bug salivary proteins. Here we report 106 mostly full-length sequences that clustered in 16 different families: Basic-tail proteins rich in lysine in the carboxy-terminal, Kunitz-containing proteins (monolaris, ixolaris and penthalaris families), proline-rich peptides, 5-, 9.4- and 18.7-kDa proteins of unknown functions, in addition to metalloproteases (class PIII-like) similar to reprolysins. We also have found a family of disintegrins, named ixodegrins that display homology to variabilin, a GPIIb/IIIa antagonist from the tick Dermacentor variabilis. In addition, we describe peptides (here named ixostatins) that display remarkable similarities to the cysteine-rich domain of ADAMST-4 (aggrecanase). Many molecules were assigned in the lipocalin family (histamine-binding proteins); others appear to be involved in oxidant metabolism, and still others were similar to ixodid proteins such as the anticomplement ISAC. We also identified for the first time a neuropeptide-like protein (nlp-31) with GGY repeats that may have antimicrobial activity. In addition, 16 novel proteins without significant similarities to other tick proteins and 37 housekeeping proteins that may be useful for phylogenetic studies are described. Some of these proteins may be useful for studying vascular biology or the immune system, for vaccine development, or as immunoreagents to detect prior exposure to ticks. Electronic version of the manuscript can be found at.
Collapse
Affiliation(s)
- Ivo M B Francischetti
- Section of Vector Biology, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892-8132, USA.
| | | | | | | | | | | | | |
Collapse
|
50
|
Kukkonen A, Peräkylä M, Akerman KEO, Näsman J. Muscarinic Toxin 7 Selectivity Is Dictated by Extracellular Receptor Loops. J Biol Chem 2004; 279:50923-9. [PMID: 15452105 DOI: 10.1074/jbc.m406424200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Muscarinic toxin 7 (MT7) is a mamba venom protein antagonist with extremely high selectivity for the M1 muscarinic acetylcholine receptor. To map the sites for the interaction of MT7 with muscarinic receptors we have used chimeric M1:M3 receptors and site-directed mutagenesis of the M3 and M4 receptor subtypes. Two Glu residues in M1, one in extracellular loop 2 and one in extracellular loop 3, were found to be important for the high affinity binding of MT7. Substitution of the corresponding Lys residues in the M3 receptor with Glu converted the M3 mutant to an MT7 binding receptor, albeit with lower affinity compared with M1. A Phe --> Tyr substitution in extracellular loop 2 of M3 together with the 2 Glu mutations generated a receptor with an increased MT7 affinity (apparent Ki = 0.26 nM in a functional assay) compared with the M1 receptor (apparent Ki = 1.31 nM). The importance of the identified amino acid residues was confirmed with a mutated M4 receptor constructs. The results indicate that the high selectivity of MT7 for the M1 receptor depends on very few residues, thus providing good prospects for future design and synthesis of muscarinic receptor-selective ligands.
Collapse
Affiliation(s)
- Anu Kukkonen
- A. I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, Kuopio University, FIN-70211 Kuopio, Finland
| | | | | | | |
Collapse
|