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Polypeptide neurotoxins from spider venoms. 总被引:1,自引:0,他引:1
E Grishin 《European journal of biochemistry》1999,264(2):276-280
Spider venoms contain a variety of toxic components. The polypeptide toxins are divided into low and high molecular mass types. Small polypeptide toxins interacting with cation channels display spatial structure homology. They can affect the functioning of calcium, sodium, or potassium channels. A family of high molecular mass toxic proteins was found in the venom of the spider genus Latrodectus. These neurotoxins, latrotoxins, cause a massive transmitter release from a diversity of nerve endings. The latrotoxins are proteins of about 1000 amino acid residues and share a high level of structure identity. The structural and functional properties of spider polypeptide toxins are reviewed in this paper. 相似文献
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蜘蛛粗毒中富含生物活性物质,尤其以多肽类成分为主. 分离鉴定了新疆穴居狼蛛粗毒中一种新的细胞裂解肽,命名为LSTX-A1,其分子量为7 335.33,含有65个氨基酸残基,且羧基端残基酰胺化.研究了LSTX-A1的细胞裂解作用,结果显示,在100 μmol/L浓度引起42% 红细胞溶血.同时LSTX-A1具有抗肿瘤作用,能抑制HeLa细胞的增殖,其IC50剂量为22 μmol/L. 相似文献
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Liang S 《Expert review of proteomics》2008,5(5):731-746
Spider venoms are an important source of novel molecules with different pharmacological properties. Recent technological developments of proteomics, especially mass spectrometry, have greatly promoted the systematic analysis of spider venom. The enormous diversity of venom components between spider species and the lack of complete genome sequence, and the limited database of protein and peptide sequences make spider venom profiling a challenging task and special considerations for technical strategies are required. This review highlights recently used methods for spider venom profiling. In general, spider venom profiling can be achieved in two parts: proteome profiling of the components with molecular weights above 10 kDa, and peptidome profiling of the components with a molecular weight of 10 kDa or under through the use of different methods. Venom proteomes are rich in various enzymes, hemocyanins, toxin-like proteins and many unknown proteins. Peptidomes are dominated by peptides with a mass of 3-6 kDa with three to five disulfide bonds. Although there are some similarities in peptide superfamily types of venoms from different spider species, the venom profile of each species is unique. The linkage of the peptidomic data with that of the cDNA approach is discussed briefly. Future challenges and perspectives are also highlighted in this review. 相似文献
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De Lima ME Figueiredo SG Pimenta AM Santos DM Borges MH Cordeiro MN Richardson M Oliveira LC Stankiewicz M Pelhate M 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,146(1-2):264-279
Arachnids have a venom apparatus and secrete a complex chemical mixture of low molecular mass organic molecules, enzymes and polypeptide neurotoxins designed to paralyze or kill their prey. Most of these toxins are specific for membrane voltage-gated sodium channels, although some may also target calcium or potassium channels and other membrane receptors. Scorpions and spiders have provided the greatest number of the neurotoxins studied so far, for which, a good number of primary and 3D structures have been obtained. Structural features, comprising a folding that determines a similar spatial distribution of charged and hydrophobic side chains of specific amino acids, are strikingly common among the toxins from spider and scorpion venoms. Such similarities are, in turn, the key feature to target and bind these proteins to ionic channels. The search for new insecticidal compounds, as well as the study of their modes of action, constitutes a current approach to rationally design novel insecticides. This goal tends to be more relevant if the resistance to the conventional chemical products is considered. A promising alternative seems to be the biotechnological approach using toxin-expressing recombinant baculovirus. Spider and scorpion toxins having insecticidal activity are reviewed here considering their structures, toxicities and action mechanisms in sodium channels of excitable membranes. 相似文献
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Corzo G Villegas E Gómez-Lagunas F Possani LD Belokoneva OS Nakajima T 《The Journal of biological chemistry》2002,277(26):23627-23637
Five amphipathic peptides with antimicrobial, hemolytic, and insecticidal activity were isolated from the crude venom of the wolf spider Oxyopes kitabensis. The peptides, named oxyopinins, are the largest linear cationic amphipathic peptides from the venom of a spider that have been chemically characterized at present. According to their primary structure Oxyopinin 1 is composed of 48 amino acid residues showing extended sequence similarity to the ant insecticidal peptide ponericinL2 and to the frog antimicrobial peptide dermaseptin. Oxyopinins 2a, 2b, 2c, and 2d have highly similar sequences. At least 27 out of 37 amino acid residues are conserved. They also show a segment of sequence similar to ponericinL2. Circular dichroism analyses showed that the secondary structure of the five peptides is essentially alpha-helical. Oxyopinins showed disrupting activities toward both biological membranes and artificial vesicles, particularly to those rich in phosphatidylcholine. Electrophysiological recordings performed on insect cells (Sf9) showed that the oxyopinins produce a drastic reduction of cell membrane resistance by opening non-selective ion channels. Additionally, a new paralytic neurotoxin named Oxytoxin 1 was purified from the same spider venom. It contains 69 amino acid residue cross-linked by five disulfide bridges. Application of mixtures containing oxyopinins and Oxytoxin 1 to insect larvae showed a potentiation phenomenon, by which an increase lethality effect is observed. These results suggest that the linear amphipathic peptides in spider venoms and neuropeptides cooperate to capture insects efficiently. 相似文献
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P B Usmanov I Kazakov D Kalikulov B U Atakuziev B A Yukelson LYaTashmukhamedov 《General physiology and biophysics》1985,4(2):185-193
It is known that Steatoda (Lityphantes) paykulliana and Latrodectus mactans tredecimguttatus spider venoms are toxic to mammals and insects. These venoms act presynaptically eliciting massive release of transmitters. They also form channels in bilayer lipid membranes (BLM) that are selective for cations. Venoms of both spider species were fractionated by gel filtration on a Sephadex G-100 column. The fraction obtained were tested on neuromuscular preparations of frog and locust and on BLM. A fraction of low molecular weight components (about 5000 daltons and less) was disclosed. This fraction showed presynaptic and channel-forming effects similar to those of crude venoms and of high molecular weight toxin fractions, obtained simultaneously from these venoms. It was shown that channels formed in BLM by crude venoms and its different fractions are identical. Also, it was found that the low molecular weight channel-forming component is a construction element of high molecular weight toxins. On the basis of data obtained a toxin structure model of the Theridiidae family spider venoms was proposed. 相似文献
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We have developed a model genetic system for analyzing the function of peptide toxins from animal venoms. We engineered and propagated strains of Drosophila melanogaster expressing heat-inducible transgenes encoding either kappa-ACTX-Hv1c or omega-ACTX-Hv1a, two insect-specific neurotoxic peptides found in the venom of the Australian funnel-web spider Hadronyche versuta. Heat induction of transgene expression for 20 min was sufficient to kill all transgenic flies, indicating that the ion channels targeted by these toxins are viable insecticide targets. The unusual phenotype of flies induced to express omega-ACTX-Hv1a recapitulates that of a hypomorphic allele of the high-voltage-activated calcium channel Dmca1D, suggesting that this is likely to be the target of omega-ACTX-Hv1a. 相似文献
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Cnidarian venoms include neurotoxins, which are able to paralyse prey organisms immediately. Important targets for neurotoxins
are voltage-gated ion channels in membranes of excitable cells. By blocking specific receptor sites, neurotoxic components
disturb the physiological ion channel functions. Here, we describe the isolation and characterisation of potential neurotoxic
polypeptides from the crude tentacle venom of the boreal scyphomedusan Cyanea capillata. Partially purified venom fractions were obtained by size-exclusion and subsequent reversed-phase chromatography. To assess
the blocking activity of the venom on voltage-gated sodium channels, we modified a mouse neuroblastoma (MNB) cell assay. Venom
fractions containing channel-blocking activity were analysed by matrix-assisted laser desorption ionisation time-of-flight
mass spectrometry (MALDI-TOF MS). The resulting mass spectra revealed a cluster of singly charged peptides within a mass range
from 3,900 to 7,000 Da. A group of three potentially neurotoxic peptides with molecular masses of 3983.4, 5795.4 and 6962.1 Da
could be tracked throughout the purification process. This investigation of the crude venom is part of a multidimensional
assay-guided approach for the isolation and structural characterisation of toxic polypeptides in northern Scyphozoa. 相似文献
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Lúcio AD Campos FV Richardson M Cordeiro MN Mazzoni MS de Lima ME Pimenta MC Bemquerer MP Figueiredo SG Gomes PC Beirão PS 《Protein and peptide letters》2008,15(7):700-708
A family of 4kDa neurotoxic peptides was purified from venoms of Phoneutria spiders. All have six cysteine residues, and low similarity with other neurotoxins. Three toxins caused moderate inhibition of L-type Ca(2+) channels. The structure of toxin PRTx27C3 was modeled and compared with toxin ADO1. The importance of four residues is suggested. 相似文献
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omega-Aga-I: a presynaptic calcium channel antagonist from venom of the funnel web spider, Agelenopsis aperta 总被引:1,自引:0,他引:1
Spider venoms are proving to be important sources of specific ion channel toxins. Venom of Agelenopsis aperta, a funnel web spider, contains a class of polypeptide toxins which blocks neuromuscular synapses at nanomolar concentrations. Detailed physiological analyses of block caused by one of these toxins, omega-Aga-I, show that it suppresses transmitter release at insect and frog neuromuscular junctions and blocks calcium spikes in insect neuronal cell bodies. omega-Aga-I may define a binding site on neuronal calcium channels which is common to both vertebrates and invertebrates. 相似文献
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Spider venoms are proving to be important sources of specific ion channel toxins. Venom of Agelenopsis aperta, a funnel web spider, contains a class of polypeptide toxins which blocks neuromuscular synapses at nanomolar concentrations. Detailed physiological analyses of block caused by one of these toxins, ω-Aga-I show that it suppresses transmitter release at insect and frog neuromuscular junctions and blocks calcium spikes in insect neuronal cell bodies. ω-Aga-I may define a binding site on neuronal calcium channels which is common to both vertebrates and invertebrates. 相似文献
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《Peptides》2014
Scorpion venoms are rich sources of biologically active peptides that are classified into disulfide-bridged peptides (DBPs) and non-disulfide-bridged peptides (NDBPs). DBPs are the main scorpion venom components responsible for the neurotoxic effects observed during scorpion envenomation as they usually target membrane bound ion channels of excitable and non-excitable cells. Several hundred DBPs have been identified and functionally characterized in the past two decades. The NDBPs represent a novel group of molecules that have gained great interest only recently due to their high diversity both in their primary structures and bioactivities. This review provides an overview of scorpion NDBPs focusing on their therapeutic applications, modes of discovery, mechanisms of NDBPs genetic diversity and structural properties. It also provides a simple classification for NDBPs that could be adopted and applied to other NDBPs identified in future studies. 相似文献
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GRETA J. BINFORD 《Biological journal of the Linnean Society. Linnean Society of London》2001,74(4):581-595
Spider venoms are complex mixtures of toxins that are used primarily for immobilizing prey. There is evidence of chemical variation in spider venoms among close relatives, yet few studies have analysed their evolution within an ecological and phylogenetic framework. On the Hawaiian archipelago, Tetragnatha, a cosmopolitan orb-weaving genus, has undergone a radiation in which a monophyletic lineage has abandoned web-building and become obligately wandering foragers. This study compares venom composition and details of feeding behaviour between orb-weaving and wandering Hawaiian Tetragnatha. Protein gel electrophoresis patterns indicated that relative to orb-weavers, wandering species had a reduced concentration of low molecular weight (<14kDa) components. Both orb-weaving and wandering Tetragnatha captured flying prey (adult lepidopterans, dipterans), but wandering spiders also captured non-flying prey (insect larvae, spiders). There were no distinct differences between orb-weavers and wanderers in prey capture and immobilization sequences, or in the paralytic effects of bites on prey. However, prey bitten by wanderers took longer to be permanently immobilized than prey bitten by orb-weavers. Contrary to predictions, there was no indication that web-loss in this group was associated with an increase in venom potency. 相似文献
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Yuan C Jin Q Tang X Hu W Cao R Yang S Xiong J Xie C Xie J Liang S 《Journal of proteome research》2007,6(7):2792-2801
The bird spider Ornithoctonus huwena Wang is a very venomous spider in China. Several compounds with different types of biological activities have been identified previously from the venom of this spider. In this study, we have performed a proteomic and peptidomic analysis of the venom. The venom was preseparated into two parts: the venom proteins with molecular weight (MW) higher than 10,000 and the venom peptides with MW lower than 10 000. Using one-dimensional gel electrophoresis (1-DE), two-dimensional gel electrophoresis (2-DE), and mass spectrometry, 90 proteins were identified, including some important enzymes, binding proteins, and some proteins with significant biological functions. For venom peptides, a combination of cation-exchange and reversed-phase chromatography was employed. More than 100 components were detected by mass spectrometry, and 47 peptides were sequenced by Edman degradation. The peptides display structural and pharmacological diversity and share little sequence similarity with peptides from other animal venoms, which indicates the venom of O. huwena Wang is unique. The venom peptides can be classified into several superfamilies. Also it is revealed that gene duplication and focal hypermutation have taken place during the evolution of the spider toxins. 相似文献
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There are now more than 40,000 identified spider species in the world, and considered about 100 species as actually dangerous to human. Spider bites cause a range of symptoms from simple swellings to disfiguring necrotic lesions, and occasionally death. While spider bites are not a major medical problem in Korea, it would be of great value to know which species of spiders pose a threat to human health. A middle molecular weight protein, sphingomyelinase D, has been identified in the venom of the brown recluse spider and strong evidence suggests that they have a major role in spider bite necrosis. For the identification of necrotizing species, we have investigated using recently developed non‐radioactive assay of sphingomyelinase for rapidly screening the necrotizing venoms. Here, we demonstrate the fetal toxicity of total 57 species (32 genera, 9 families) of the wandering spiders among 622 identified spider species in Korea. It has been revealed that two species of the Thomisidae spider, Ozyptila nongae (0.2467) and Diaea subdola (0.2020) have the strongest sphingomyelinase activities among themselves. In addition one species of the family Pisauridae, Dolomedes sulfureus (0.2341) has also relatively higher value comparing to other wandering spiders. However comparing to that of the brown recluse spider, Loxosceles reclusa (1.814) in North America the necrotizing activities of these Korean wandering species are still very low state, so there seems to be little possibilities to create serious medical problems by the necrotizing arachnidism in Korean peninsula. 相似文献