| [chronic excretion of salmonella and arizona bacilli by the species vipera ammodytes ammodytes (sandviper)]. | | 1964 | 5825935 |
| [experimental study on the poisoning caused by the venom of the bulgarian sandviper vipera ammodytes ammodytes]. | | 1965 | 5846330 |
| [experimental infection of snakes vipera ammodytes ammodytes with salmonella and arizona bacteria]. | | 1967 | 6048580 |
| influence of calcium on the action of vipera ammodytes ammodytes snake venom on the myocardium. | v. ammodytes ammodytes snake venom produced irreversible block of the isolated, artificially stimulated rat right ventricle or isolated rat heart. this was the result of degenerative changes of the myocardium caused by the direct effect of toxic components of the venom. an excess of ca2+ could temporarily restart the contractions. | 1983 | 6658810 |
| identification of the neuronal acceptor in bovine cortex for ammodytoxin c, a presynaptically neurotoxic phospholipase a2. | a specific, high-affinity binding site for ammodytoxin c in synaptic membranes from bovine cerebral cortex was detected and partially characterized. equilibrium binding analysis revealed a single population of [125i]ammodytoxin c acceptors with the following binding parameters: kd = 6.0 nm and bmax = 5.7 pmol/mg membrane protein. such binding was strongly inhibited by three ammodytoxins (a, b, and c) and by crotoxin b. vipera berus berus phospholipase a2 was a weaker inhibitor; nontoxic phosphol ... | 1994 | 7947800 |
| a comparison of ovine and equine antivenoms. | commercial antivenoms produced in horses were compared with monospecific antivenoms raised in sheep against crotalus durissus terrificus, crotalus atrox, crotalus adamanteus, micrurus fulvius fulvius, naja naja, naja kaouthia, echis ocellatus, vipera lebetina deserti, vipera berus berus and vipera ammodytes ammodytes venom. antibodies raised by immunizing sheep with c. d. terrificus venom were more effective than their equine counterparts in preventing lethal toxicity in mice (ed50), in inhibiti ... | 1994 | 8052997 |
| [on salmonella species in reptiles (new arizona species in the poisonous snake vipera ammodytes ammodytes)]. | | 1963 | 14166430 |
| the role of antibodies specific for toxic spla2s and haemorrhagins in neutralizing potential of antisera raised against vipera ammodytes ammodytes venom. | the contribution of antibodies directed against the two main toxic groups of proteins in the vipera ammodytes ammodytes venom, haemorrhagic metalloproteinases (h) and neurotoxic spla2s (atxs), to the overall protective efficacy of the whole venom antisera was investigated. using elisa assays we established a high correlation between the protective efficacy of the whole venom antisera in mice and their anti-atxs antibody content. as the haemorrhage is the prevailing toxic effect of the venom in h ... | 2008 | 18571473 |
| dose dependent effects of standardized nose-horned viper (vipera ammodytes ammodytes) venom on parameters of cardiac function in isolated rat heart. | direct, dose dependent effects of the nose-horned vipers (vipera ammodytes ammodytes) venom on various parameters of cardiac action in isolated rat hearts were examined. biochemical (protein content, sds polyacrylamide gel electrophoresis) and biological (minimum haemorrhagic and necrotizing dose and lethal dose (ld(50))) characterization of the venom was performed before testing. the hearts were infused with venom doses of 30, 90 and 150 microg/ml for 10 min followed by 30 min of wash out perio ... | 2008 | 18313364 |
| sequences and structural organization of phospholipase a2 genes from vipera aspis aspis, v. aspis zinnikeri and vipera berus berus venom. identification of the origin of a new viper population based on ammodytin i1 heterogeneity. | we used a pcr-based method to determine the genomic dna sequences encoding phospholipases a2 (pla2s) from the venoms of vipera aspis aspis (v. a. aspis), vipera aspis zinnikeri (v. a. zinnikeri), vipera berus berus (v. b. berus) and a neurotoxic v. a. aspis snake (neurotoxic v. a. aspis) from a population responsible for unusual neurotoxic envenomations in south-east france. we sequenced five groups of genes, each corresponding to a different pla2. the genes encoding the a and b chains of vaspin ... | 2003 | 12823540 |
| phenylalanine-24 in the n-terminal region of ammodytoxins is important for both enzymic activity and presynaptic toxicity. | ammodytoxins (atxs) are group ii phospholipases a(2) (pla(2)s) with presynaptic toxicity from venom of the snake vipera ammodytes ammodytes. the molecular basis of their neurotoxicity, and that of similar pla(2) toxins, is still to be explained. to address this problem, a surface-exposed aromatic residue, phe(24), in the n-terminal region of the most potent atx, atxa, was replaced by other aromatic (tyrosine, tryptophan), hydrophobic (alanine) and polar uncharged (serine, asparagine) residues. t ... | 2002 | 11931665 |
| mrna secondary structure can greatly affect production of recombinant phospholipase a(2) toxins in bacteria. | the neurotoxic activity of ammodytoxin a (atxa), a phospholipase a(2) from vipera ammodytes ammodytes venom, has been investigated by protein engineering. with the aim of obtaining atxa as a non-fused protein in the bacterial cytoplasm and avoiding problems with incomplete cleavage in vivo of the initial met preceding the first residue (ser1), a double mutant (s1a/e4q) was prepared and expressed in escherichia coli. immunoblotting of the bacterial lysate showed that the mutant was synthesized at ... | 2002 | 11821126 |
| the amino acid region 115-119 of ammodytoxins plays an important role in neurotoxicity. | quadruple (y115k/i116k/r118m/n119l) and double (y115k/i116k) mutants of ammodytoxin a, a presynaptically toxic phospholipase a(2) from vipera ammodytes ammodytes venom, were prepared and characterized. the enzymatic activity of the quadruple mutant on phosphatidylcholine micelles was threefold higher than that of atxa, presumably due to higher phospholipid-binding affinity, whereas the activity of the double mutant was twofold lower. the substantial decrease by more than two orders of magnitude ... | 2000 | 11027615 |
| an aromatic, but not a basic, residue is involved in the toxicity of group-ii phospholipase a2 neurotoxins. | ammodytoxins (atxs) a, b and c are basic phospholipase a2s from vipera ammodytes ammodytes snake venom, and they exhibit presynaptic toxicity. the most toxic is atxa, followed by atxc, its naturally occurring f124-->i/k128-->e mutant, which is 17 times less toxic. two mutants of atxa have been produced in bacteria and characterized. the specific enzymic activity of the k128-->e mutant on mixed phosphatidylcholine/triton x-100 micelles is similar to that of the wild type. the k108-->n/k111-->n mu ... | 1999 | 10377255 |
| expression of fully active ammodytoxin a, a potent presynaptically neurotoxic phospholipase a2, in escherichia coli. | a cdna encoding the most presynaptically neurotoxic phospholipase a2, ammodytoxin a, from the venom of the long-nosed viper (vipera ammodytes ammodytes) has been expressed in escherichia coli. ammodytoxin a was produced as a fusion protein with the 81 n-terminal residues of adenylate kinase followed by the tetrapeptide recognition site for factor xa (iegr) just preceding the first amino acid residue of the toxin. the fusion protein was expressed under the control of tac promoter without iptg ind ... | 1993 | 8224227 |
| ammodytoxin a acceptor in bovine brain synaptic membranes. | ammodytoxin a, the presynaptic neurotoxin from vipera ammodytes ammodytes venom, was found to bind specifically and with high affinity to bovine cortex synaptic membrane preparation. the detected ammodytoxin a high-affinity binding was characterized by equilibrium binding analysis which revealed a single high-affinity binding site with kd 4.13 nm and bmax 6.67 pmoles/mg of membrane protein. 125i-ammodytoxin a was covalently cross-linked to its neuronal acceptor using a chemical cross-linking tec ... | 1995 | 7570629 |
| snake venomics of the siamese russell's viper (daboia russelli siamensis) -- relation to pharmacological activities. | the venom proteome of daboia russelli siamensis, a snake of medical importance in several asian countries, was analysed by 2-d electrophoresis, subsequent ms/ms and enzymatic assays. the proteome comprises toxins from six protein families: serine proteinases, metalloproteinases, phospholipases a(2), l-amino acid oxidases, vascular endothelial growth factors and c-type lectin-like proteins. the venom toxin composition correlates with the clinical manifestation of the russell's viper bite and expl ... | 2009 | 19457351 |
| histopathological changes in rat myocardium caused by vipera ammodytes ammodytes (european viper) snake venom. | the application of vipera ammodytes ammodytes snake venom, either crude venom or fractions 5 and 6 of the 11 obtained from a sephadex g-100 column, produced parenchymal degeneration of the myocardium of isolated rat hearts. | 1983 | 6623489 |
| serine proteinase inhibitors from vipera ammodytes venom. isolation and kinetic studies. | three protein inhibitors of serine proteinases were isolated from the crude venom of the long-nosed viper vipera ammodytes ammodytes by ion-exchange and gel chromatography. two of them strongly inhibit trypsin (ki = 3.4 x 10(-10) and 5.6 x 10(-10) m), while the third one primarily inhibits chymotrypsin (ki = 4.3 x 10(-9) m). their mr values are close to 7000, and pi is 9.8 in both trypsin inhibitors and 10.0 in the chymotrypsin inhibitor. the n-terminal group in the former inhibitors is blocked; ... | 1983 | 6602050 |
| ammodytoxin a, a highly lethal phospholipase a2 from vipera ammodytes ammodytes venom. | the amino acid sequence of ammodytoxin a, the most toxic presynaptically active phospholipase a2 isolated from vipera ammodytes ammodytes venom, was determined. the primary structure was deduced from peptides obtained by staphylococcus aureus proteinase and trypsin digestion of reduced and carboxymethylated protein and from the automated edman degradation of the n-terminal part of the non-reduced molecule. according to the sequence, the enzyme classifies to the subgroup iia of the phospholipase ... | 1985 | 3986212 |
| amino-acid sequence of ammodytoxin b partially reveals the location of the site of toxicity of ammodytoxins. | the complete amino-acid sequence of ammodytoxin b, a presynaptically toxic phospholipase a2 isolated from vipera ammodytes ammodytes venom, was determined by manual and automated protein sequencing. ammodytoxin b (i.v. ld50 = 0.58 mg/kg for white mice) is 30-fold less toxic than ammodytoxin a, the most toxic phospholipase isolated from the same venom. the two proteins (each 122 residues long) differ in only 3 residues located in positions 115, 118 and 119 (numbering according to r. renetseder et ... | 1986 | 3790259 |
| the amino acid sequence of a myotoxic phospholipase from the venom of bothrops asper. | a myotoxic, basic phospholipase a2 (pi greater than 9.5) with anticoagulant activity has been purified from the venom of bothrops asper, and its amino acid sequence determined by automated edman degradation. it is distinct from the b. asper phospholipase a2 known as myotoxin i [lomonte, b. and gutierrez, j. m., 1989, toxicon 27, 725] but cross-reacts with myotoxin i rabbit antisera, suggesting that the proteins are closely related isoforms. to our knowledge, this is the first myotoxic phospholip ... | 1990 | 2327788 |
| neutralization of the activity of vipera ammodytes ammodytes snake venom on myocardium of rats by antitoxinum viperinum: a histopathological study. | antitoxinum viperinum was tested for its ability to prevent alteration of the myocardium induced by vipera ammodytes ammodytes venom. antivenom was injected intraperitoneally either immediately, 30 min or 2 hr after the intraperitoneal injection of venom. the light microscopic examination showed that the antiserum neutralized the effects of venom and antivenom might be useful in treating v.a. ammodytes venom poisoning. | 1991 | 1818120 |
| purification and properties of a kininogenin from the venom of vipera ammodytes ammodytes. | a kininogenin (ec 3.4.21.8) was purified from the venom of vipera ammodytes ammodytes (european sand viper) by a combination of gel filtration and ion-exchange chromatography. the enzyme is approximately six times more active than bovine trypsin in its ability to release vasoactive peptides from a plasma precursor. the kininogenin is a glycoprotein containing 18-20% by weight of carbohydrate. it showed a mol. wt. of 40500 on gel filtration. gel electrophoresis of the reduced sample in the presen ... | 1976 | 1275896 |
| neutralization of vipera and macrovipera venoms by two experimental polyvalent antisera: a study of paraspecificity. | we conducted an extensive study of neutralization of lethality of 11 species and one subspecies of snakes of the genus vipera, and of five species of macrovipera, by two experimental equine antisera. one antiserum was a trivalent preparation raised against the venoms of vipera aspis aspis, vipera berus berus and vipera ammodytes ammodytes; the other was a pentavalent preparation that also included venoms of vipera (now montivipera) xanthina and macrovipera lebetina obtusa. we measured specific n ... | 2011 | 21530569 |
| structural and biochemical characterisation of vaf1, a p-iiia fibrinogenolytic metalloproteinase from vipera ammodytes ammodytes venom. | a high molecular mass metalloproteinase with α-fibrinogenolytic activity, termed vaf1, was purified from nose-horned viper (vipera ammodytes ammodytes) venom. subcutaneous injection of 9 μg of vaf1 did not induce bleeding in rats. nevertheless, in vitro it degraded collagen iv, nidogen and fibronectin, components of the extracellular matrix, although with low efficacy and narrow specificity. vaf1 would be expected to exert anti-coagulant action, due to its hydrolysis of fibrinogen, factor x, pro ... | 2015 | 25549999 |
| intraspecies variability in vipera ammodytes ammodytes venom related to its toxicity and immunogenic potential. | vipera ammodytes is the most venomous european snake, whose venom has been used as antigen for immunization of antivenom-producing animals. same as venom of any other snake, it is a complex mixture of proteins, peptides and other compounds which biochemical and pharmacological variability has been demonstrated at interspecies and intraspecies level. in this work we demonstrated intraspecific variability between 8 venom production batches using both the conventional and the new methodology. moreo ... | 2010 | 20971215 |
| severe coagulopathy after vipera ammodytes ammodytes snakebite in bulgaria: a case report. | the case report presents a severe coagulopathy in a 56-year-old man following envenomation by the snake (vipera ammodytes ammodytes) on his left hand. initially the man was in shock, with an extremely low blood pressure and tachycardia. local signs included a painful blister formation on the envenomation site. twenty-four hours later, the man developed acute thrombocytopenia (platelets number 10 x 10(9)/l) and ecchimoses formation on the affected limb and on the left side of his body due to a di ... | 2010 | 20600226 |
| ammodytoxin content of vipera ammodytes ammodytes venom as a prognostic factor for venom immunogenicity. | venoms are complex mixtures of proteins, peptides and other compounds whose biochemical and biological variability has been clearly demonstrated. these molecules have been used as antigens for immunization of anti-venom-producing animals (horses or sheep). ammodytoxins (atx) are potently neurotoxic compounds, and the most toxic compounds isolated so far from the vipera ammodytes ammodytes (vaa) venom. recently we have shown that the level of antibodies specific to vaa venom's most toxic componen ... | 2010 | 20139032 |
| ultrastructural evidence for the uptake of a neurotoxic snake venom phospholipase a2 into mammalian motor nerve terminals. | a mutant form of ammodytoxin a, a neurotoxic phospholipase a(2) from the venom of the long nosed viper vipera ammodytes ammodytes, was prepared by site-directed mutagenesis, conjugated to a nanogold particle and inoculated into the antero-lateral aspect of one hind limb of female mice. eight hours later the mice were killed, the soleus muscles of both ipsi- and contra-lateral hind limbs were removed, exposed to a silver enhancing medium and then prepared for transmission electron microscopy. sil ... | 2009 | 19631643 |
| neurotoxicity of ammodytoxin a in the envenoming bites of vipera ammodytes ammodytes. | envenoming bites by vipera ammodytes ammodytes (the long-nosed viper) can cause life-threatening neurotoxicity, particularly in children. we investigated the mechanisms of the neurotoxicity of ammodytoxin a, the principal toxin in the venom of these snakes, in isolated nerve-muscle preparations from mice. the toxin was bound selectively to the neuromuscular junction, and at concentrations similar to those likely to be found in the circulation of young bite victims, it blocked the response of the ... | 2008 | 18800006 |
| ammodytagin, a heterodimeric metalloproteinase from vipera ammodytes ammodytes venom with strong hemorrhagic activity. | ammodytagin, a hemorrhagic zn(2+)-dependent metalloproteinase from vipera ammodytes ammodytes (vaa) venom, is a glycosylated heterodimer of 108 kda, as determined by maldi mass spectrometry. partial amino acid sequencing by edman degradation and ms/ms analysis identified sequences belonging to metalloproteinase, disintegrin-like and cysteine-rich domains, which in addition to its heterodimeric nature allows classification into the p-iiic group of snake venom metalloproteinases (svmps). only few ... | 2011 | 21933678 |
| a recent evaluation of the lethal potencies of ammodytoxins. | ammodytoxin a (atxa) is the most toxic secreted phospholipase a(2) of the three isotoxins with presynaptic neurotoxicity, isolated from the venom of the nose-horned viper (vipera ammodytes ammodytes), with an ld(50) of 21 μg/kg in mice. the toxic potencies of two other isoforms have been re-evaluated using highly purified recombinant proteins, with their intraperitoneal ld(50)s determined as 960 μg/kg for atxb and 310 μg/kg for atxc. atxb and atxc differ from atxa in only three and two amino aci ... | 2012 | 22406514 |
| binding to the high-affinity m-type receptor for secreted phospholipases a(2) is not obligatory for the presynaptic neurotoxicity of ammodytoxin a. | r180, isolated from porcine brain cortex, is a high-affinity membrane receptor for ammodytoxin a (atxa), a secreted phospholipase a(2) (spla(2)) and presynaptically active neurotoxin from venom of the long-nosed viper (vipera ammodytes ammodytes). as a member of the m-type spla(2) receptors, present on the mammalian plasma membrane, r180 has been proposed to be responsible for one of the first events in the process of presynaptic neurotoxicity, the binding of the toxin to the nerve cell. to test ... | 2006 | 16815622 |
| the c-terminal and beta-wing regions of ammodytoxin a, a neurotoxic phospholipase a2 from vipera ammodytes ammodytes, are critical for binding to factor xa and for anticoagulant effect. | ammodytoxin a (atxa) from the venom of vipera ammodytes ammodytes belongs to group iia secreted phospholipase a2 (spla2), for which the major pathologic activity is presynaptic neurotoxicity. we show here that this toxin also affects hemostasis because it exhibits strong anticoagulant activity. atxa binds directly to human coagulation factor xa (fxa) with kdapp of 32 nm, thus inhibiting the activity of the prothrombinase complex with an ic50 of 20 nm. to map the fxa-interaction site on atxa, var ... | 2006 | 16039772 |
| the variability of vipera ammodytes ammodytes venoms from croatia--biochemical properties and biological activity. | vipera ammodytes ammodytes venom has been used for many years in croatia for immunization of horses and production of specific therapeutic anti-venoms. the neutralizing effectiveness of anti-venoms is directly dependent on the properties of the snake venom used for immunization. therefore, appropriate characterization of the whole venom is necessary prior to use in the immunization procedure. in the course of such analyses, the variability in biochemical properties and biological activity was ob ... | 2005 | 15907770 |
| infant death after nose-horned viper (vipera ammodytes ammodytes) bite in croatia: a case report. | a case of a 45-day-old male infant, bitten on the neck by nose-horned viper (vipera ammodytes ammodytes), is reported. this episode occurred while the baby was on a picnic with his parents in a hill near a town in southern croatia. in spite of immediate arrival at hospital, where antivenom was administrated and all the necessary treatment measures were carried out, the infant died 6 h following the bite. the cause of death was severe and progressive hyperkalaemia, massive intravascular haemolysi ... | 2010 | 20813122 |
| comparative structural studies of two natural isoforms of ammodytoxin, phospholipases a2 from vipera ammodytes ammodytes which differ in neurotoxicity and anticoagulant activity. | ammodytoxin a (atxa) and its natural isoform atxc from the venom of vipera ammodytes ammodytes belong to group iia-secreted phospholipases a(2) which catalyze the hydrolysis of glycerophospholipids and exhibit strong neurotoxic and anticoagulant effects. the two isoforms, which differ in sequence by only two amino acid residues (phe124>ile and lys128>glu), display significant differences in toxicity and anticoagulant properties and act on protein targets including neurotoxic proteic receptors an ... | 2010 | 19857576 |
| isolation, crystallization and preliminary x-ray diffraction analysis of l-amino-acid oxidase from vipera ammodytes ammodytes venom. | l-amino-acid oxidase from the venom of vipera ammodytes ammodytes, the most venomous snake in europe, was isolated and crystallized using the sitting-drop vapour-diffusion method. the solution conditions under which the protein sample was monodisperse were optimized using dynamic light scattering prior to crystallization. the crystals belonged to space group c2, with unit-cell parameters a = 198.37, b = 96.38, c = 109.11 a, beta = 92.56 degrees . initial diffraction data were collected to 2.6 a ... | 2008 | 18931435 |
| comparative analysis of the venom proteomes of vipera ammodytes ammodytes and vipera ammodytes meridionalis. | the venom proteomics of vipera ammodytes ammodytes and vipera ammodytes meridionalis, snakes of public health significance and the most poisonous reptiles in europe, were analyzed by fplc, 2-d electrophoresis, sequence analysis, and ms/ms. fplc analysis showed the presence of l-amino acid oxidase, monomeric and heterodimeric phospholipases a2, c-type lectin protein, and proteinases in the venom of v. a. ammodytes. representatives of the same protein families were found in the venom of the other ... | 2008 | 18257516 |
| protein disulphide isomerase binds ammodytoxin strongly: possible implications for toxin trafficking. | ammodytoxin, a group iia secreted phospholipase a(2) from the venom of the long-nosed viper (vipera ammodytes ammodytes), is a potent presynaptically acting neurotoxin. it blocks the secretion of neurotransmitter from the nerve cell, thus hindering the communication with the neighbouring neuron or muscle cell. to express the neurotoxicity, ammodytoxin should interact with specific receptors in the axon terminal and express phospholipase activity. our previous results indicate that, following the ... | 2005 | 15737647 |
| ammodytase, a metalloprotease from vipera ammodytes ammodytes venom, possesses strong fibrinolytic activity. | ammodytase, a high molecular mass metalloproteinase with fibrinogenolytic and fibrinolytic activities, was purified from long-nosed viper (vipera ammodytes ammodytes) venom by gel filtration, affinity and ion-exchange chromatographies. the enzyme is a single-chain glycoprotein with apparent molecular mass of 70 kda and isoelectric point of 6.6. ammodytase shows very weak hemorrhagic activity, and only at doses higher than 20 microg. consistent with this, it partially degrades some components of ... | 2007 | 17250863 |
| toxicity evolution of vipera aspis aspis venom: identification and molecular modeling of a novel phospholipase a(2) heterodimer neurotoxin. | we report the simultaneous presence of two phospholipase a(2) (pla(2)) neurotoxins in the venom of vipera aspis aspis, the first such observation. one is monomeric and identical to ammodytoxin b of vipera ammodytes ammodytes. its presence may result from gene flux after interbreeding between v. aspis aspis and v. ammodytes ammodytes. the second, a novel heterodimer named vaspin, is very similar to vipoxin of vipera ammodytes meridionalis and to pla(2)-i of vipera aspis zinnikeri. it may result f ... | 2002 | 12220671 |
| purification and characterisation of two hemorrhagic metalloproteinases from the venom of the long-nosed viper, vipera ammodytes ammodytes. | two hemorrhagic proteins, vah1 and vah2, have been purified from vipera ammodytes ammodytes venom. they are monomeric glycoproteins of an apparent molecular mass of 70kda and multiple isoelectric points around ph 5.5. both molecules are proteolytically active against azocasein as substrate. vah1, which was characterised in detail, showed maximum activity at ph 7.5. ethylenediaminetetraacetic acid eliminated the proteolytic as well as the hemorrhagic activity of vah1 while iodoacetamide, phenylme ... | 2002 | 11602279 |
| crystallization and preliminary x-ray analysis of vipoxin, a complex between a toxic phospholipase a2 and its natural polypeptide inhibitor. | the toxin vipoxin, which is a complex between a basic toxic phospholipase a2 and an acidic non-toxic protein inhibitor, is found in the venom of the bulgarian viper (vipera ammodytes ammodytes), the most toxic snake in europe. the two polypeptide chains each consist of 122 residues and are highly homologous (62%). the vipoxin complex is the first reported example of a high degree of structural homology between an enzyme and its natural inhibitor. the present crystals diffract in the x-ray beam t ... | 1993 | 8510159 |
| hemorrhagin vah4, a covalent heterodimeric p-iii metalloproteinase from vipera ammodytes ammodytes with a potential antitumour activity. | in the envenomation caused by a bite of vipera ammodytes ammodytes, the most venomous snake in europe, hemorrhage is usually the most severe consequence in man. identifying and understanding the hemorrhagic components of its venom is therefore particularly important in optimizing medical treatment of patients. we describe a novel high molecular mass hemorrhagin, vah4. the isolated molecule is a covalent dimer of two homologous subunits, vah4-a and vah4-b. complete structural characterization of ... | 2014 | 24269369 |
| crystallographic characterization of functional sites of crotoxin and ammodytoxin, potent β-neurotoxins from viperidae venom. | this review will focus on a description of the three-dimensional structures of two β-neurotoxins, the monomeric pla(2) ammodytoxin from vipera ammodytes ammodytes, and heterodimeric crotoxin from crotalus durissus terrificus, and a detailed structural analysis of their multiple functional sites. we have recently determined at high resolution the crystal structures of two natural isoforms of ammodytoxin (atxa and atxc) (saul et al., 2010) which exhibit different toxicity profiles and different an ... | 2012 | 22683534 |
| a phospholipase a2-like pseudogene retaining the highly conserved introns of mojave toxin and other snake venom group ii pla2s, but having different exons. | mojave toxin is a neurotoxic, heterodimeric phospholipase a2 (pla2) from the venom of the mojave rattlesnake (crotalus scutulatus scutulatus) and is characteristic of all rattlesnake presynaptic neurotoxins. here, we describe a phospholipase a2 pseudogene (psi-mtx) located 2,000 nucleotides upstream, and on the opposite dna strand, from a gene for mojave toxin acidic subunit (mtx-a). the pseudogene lacks the first exon and a few segments of noncoding dna found in functional snake venom pla2 gene ... | 1996 | 8769568 |
| two coagulation factor x activators from vipera a. ammodytes venom with potential to treat patients with dysfunctional factors ixa or viia. | two activators of coagulation factor x, 58kda vafxa-i and 70kda vafxa-ii, were purified from the venom of long-nosed viper (vipera ammodytes ammodytes) by chromatography on gel filtration, affinity, ion-exchange and hydroxyapatite media. both enzymes are glycoproteins composed of a heavy chain and two c-type lectin-like light chains all joined by disulphide bonds. lc-ms and lc-ms/ms analysis of their tryptic fragments demonstrated that the heavy chain consists of three domains, metalloproteinase ... | 2008 | 18760294 |
| specific distribution of vegf-f in viperinae snake venoms: isolation and characterization of a vgef-f from the venom of daboia russelli siamensis. | vascular endothelial growth factor exerts multiple functions through binding to two distinct receptor tyrosine kinases, flt-1 and kdr. we previously demonstrated that snake venom vegfs, designated vegf-fs, exhibit potent biological activities when compared with vegf165 and that they selectively recognize kdr. we herein report the screening of several snake venoms for vegf-fs using antibodies against vammin and hf, vegf-fs derived from the venom of vipera ammodytes ammodytes and vipera aspis aspi ... | 2005 | 15992764 |
| a neurotoxic complex from the venom of the bulgarian viper (vipera ammodytes ammodytes) and partial amino acid sequence of the toxic phospholipase a2. | | 1978 | 622724 |
| subfractionation and recombination of a neurotoxic complex from the venom of the bulgarian viper (vipera ammodytes ammodytes). | | 1977 | 16779 |
| action on phosphatidylcholine of the toxic phospholipase a2 from the venom of bulgarian viper (vipera ammodytes ammodytes). | | 1976 | 13518 |
| identification of a novel binding site for calmodulin in ammodytoxin a, a neurotoxic group iia phospholipase a2. | the molecular mechanism of the presynaptic neurotoxicity of snake venom phospholipases a2 (pla2s) is not yet fully elucidated. recently, new high-affinity binding proteins for pla2 toxins have been discovered, including the important intracellular ca2+ sensor, calmodulin (cam). in the present study, the mode of interaction of group iia pla2s with the ca2+-bound form of cam was investigated by mutational analysis of ammodytoxin a (atxa) from the long-nosed viper (vipera ammodytes ammodytes). seve ... | 2003 | 12846835 |
| chip electrophoretic separation of highly homologous ammodytoxin isoforms: three neurotoxic phospholipases a2 of vipera ammodytes ammodytes venom. | ammodytoxins (atxs), a group of ca(2+) -dependent neurotoxic phospholipases a2 of vipera ammodytes ammodytes venom, are mainly responsible for venom toxicity. within the atx group, ld50 values between three isoforms, a, b, and c are differing with atxa exhibiting an ld50 value by an order of magnitude lower (more toxic) than the other two isoforms. this difference in toxicity justifies the necessity to prepare suitable antibodies and thus isoform separation to characterize the atx content of vip ... | 2014 | 24431226 |
| [effect of vipera ammodytes ammodytes venom on the isolated heart]. | | 1963 | 14119200 |
| lethal herpesvirosis in 16 captive horned vipers (vipera ammodytes ammodytes): pathological and ultrastructural findings. | sixteen captive adult horned vipers (vipera ammodytes ammodytes) were submitted for necropsy examination following a 2-week history of lethargy, anorexia and dyspnoea. gross lesions included widespread haemorrhage, serosanguineous effusions in the body cavities and multiple pinpoint white to yellow foci in the liver. microscopically, there was multifocal hepatic coagulative necrosis associated with intranuclear acidophilic inclusion bodies in sinusoidal endothelial cells. similar endothelial les ... | 2014 | 24309907 |
| vasp1, catalytically active serine proteinase from vipera ammodytes ammodytes venom with unconventional active site triad. | vasp1, a serine proteinase from vipera ammodytes ammodytes venom, is a glycosylated monomer of 31.5 kda, as determined by maldi mass spectrometry, showing multiple isoelectric points between ph 6.5 and ph 8.5. partial amino acid sequencing of vasp1 by edman degradation and ms/ms analysis identified sequences which allowed its classification among the so-called snake venom serine proteinase homologues, members of the peptidase s1 family, however being devoid of the canonical catalytic triad. only ... | 2014 | 24269689 |
| identification of proteins interacting with ammodytoxins in vipera ammodytes ammodytes venom by immuno-affinity chromatography. | in order to perform their function, proteins frequently interact with other proteins. various methods are used to reveal protein interacting partners, and affinity chromatography is one of them. snake venom is composed mostly of proteins, and various protein complexes in the venom have been found to exhibit higher toxicity levels than respective components separately. complexes can modulate envenomation activity of a venom and/or potentiate its effect. our previous data indicate that the most to ... | 2014 | 24217948 |
| vah3, one of the principal hemorrhagins in vipera ammodytes ammodytes venom, is a homodimeric p-iiic metalloproteinase. | hemorrhage is the most potent manifestation of envenomation by vipera ammodytes ammodytes (v. a. ammodytes) venom in man. a detailed description of the venom components contributing to this effect is thus medically very important. we have characterized a novel component, termed here vah3, as a potently hemorrhagic snake venom metalloproteinase (svmp). its proteolytic activity and overall stability depend on the presence of zn(2+) and ca(2+) ions. the molecular mass of this slightly acidic molecu ... | 2013 | 23321470 |
| preliminary evaluation of total protein concentration and electrophoretic protein fractions in fresh and frozen serum from wild horned vipers (vipera ammodytes ammodytes). | determination of the health status of reptiles is based on physical examination and evaluation of hematologic and biochemical values. evaluation of serum total protein (tp) concentration and protein fractions plays an important role in health assessment; however, little is known about references value for these analytes in wild viperoid snakes. in addition, studies evaluating the stability of proteins in frozen viperoid serum are lacking. | 2012 | 23078521 |
| chromatography, mass spectrometry, and molecular modeling studies on ammodytoxins. | the ammodytoxins (atxs) are neurotoxic phospholipases which occur in vipera ammodytes ammodytes (vaa) snake venom. there are three atx isoforms, a, b, and c, which differ in only five amino acid positions at the c-terminus but differ substantially in their toxicity. the objective of this study was to establish an analytical method for unambiguous identification of all three isoforms and to use the method to assess a procedure for purification of the most toxic phospholipase, atxa, from the venom ... | 2012 | 22349324 |
| studying disulfide bond rearrangement by maldi-rtof psd and maldi-tof/rtof high-energy cid (20 kev) experiments of peptides derived from ammodytoxins. | ammodytoxins (atxs) are presynaptically neurotoxic phospholipases present in vipera ammodytes ammodytes snake venom. atxs show a high sequence homology and contain 14 cysteines which form seven biologically relevant disulfide bridges-connecting non-neighboring cysteines. formic acid cleavage was performed to confirm protein sequences by maldi rtof ms and resulted in 95.6% sequence coverage exhibiting only few formylations. cysteine-containing peptides showed adjacent signals 2 and/or 4 da lower ... | 2011 | 21259390 |
| the structure of a native l-amino acid oxidase, the major component of the vipera ammodytes ammodytes venomic, reveals dynamic active site and quaternary structure stabilization by divalent ions. | the crystal structure of the major component of the vipera ammodytes ammodytes venomic, a flavotoxin, member of the l-amino acid oxidase (laao) family, has been determined and refined at 2.6 å resolution. the asymmetric unit consists of four molecules, each bound to oxidized fad, representing a dimer of dimers. the binding of four zn(2+) ions stabilizes the enzymatically active quaternary structure and is considered important for the biological activity of laao and other flavoproteins. each mono ... | 2011 | 20938508 |
| the first phospholipase inhibitor from the serum of vipera ammodytes ammodytes. | ammodytoxins are neurotoxic secretory phospholipase a(2) molecules, some of the most toxic components of the long-nosed viper (vipera ammodytes ammodytes) venom. envenomation by this and by closely related vipers is quite frequent in southern parts of europe and serotherapy is used in the most severe cases. because of occasional complications, alternative medical treatment of envenomation is needed. in the present study, ammodytoxin inhibitor was purified from the serum of v. a. ammodytes using ... | 2007 | 17970753 |
| amino acid and cdna sequences of a neutral phospholipase a2 from the long-nosed viper (vipera ammodytes ammodytes) venom. | the amino acid sequence of a non-toxic phospholipase a2, ammodytin i2, from the venom of the long-nosed viper (vipera ammodytes ammodytes) and its cdna sequence have been determined. the protein sequence was elucidated by sequencing the peptides generated by cnbr cleavage, mild acid hydrolysis and tryptic digestion of maleylated and non-maleylated protein. sequencing of the cdna showed that the protein is synthesized as an 137-amino-acid-residue precursor molecule consisting of a 16-residue sign ... | 1992 | 1551386 |
| primary structure of ammodytoxin c further reveals the toxic site of ammodytoxin. | the sequence of ammodytoxin c, a presynaptically toxic, basic phospholipase a2 of vipera ammodytes ammodytes venom was determined. the toxin differs only in two amino acid residues from the most toxic isotoxin ammodytoxin a and is 18-times less lethal. ammodytoxin b which is 30-times less lethal than ammodytoxin a differs from it only in three amino acid residues. from the three-dimensional model of ammodytoxin a, it can be seen that mutated regions of ammodytoxin b and ammodytoxin c are on the ... | 1989 | 2597708 |
| sequence homology between phospholipase and its inhibitor in snake venom. the primary structure of phospholipase a2 of vipoxin from the venom of the bulgarian viper (vipera ammodytes ammodytes, serpentes). | the amino-acid sequence of phospholipase a2 from the neurotoxin vipoxin of the bulgarian viper (vipera ammodytes ammodytes, serpentes) is presented. the enzyme consists of 122 amino-acid residues including 7 disulfide bonds and thus belongs to phospholipases a2 group iia. the sequence was determined by automatic edman degradation of the intact chain and of the peptides obtained after tryptic hydrolysis of the oxidized chain. the short cleavage time of 30 min and another limited tryptic digestion ... | 1987 | 3606821 |
| study of the neurotoxic complex and its components from the venom of the bulgarian sand viper vipera ammodytes ammodytes: interaction of the acidic component with cations. | | 1980 | 7362253 |
| the standard mouse assay of anti-venom quality does not measure antibodies neutralising the haemorrhagic activity of vipera ammodytes venom. | the venom of vipera ammodytes ammodytes (vaa), like the venoms of other viperinae snakes, is largely haemorrhagic and necrotising, and only to a lesser extent neurotoxic to humans. the components most extensively studied so far, and most probably involved in generating the observed pathologies, are haemorrhagins (h), members of the metalloproteinase group of enzymes, and neurotoxic ammodytoxins (atxs), that belong to the secretory phospholipases a2. rabbit antisera were prepared containing funct ... | 2012 | 22445824 |
| sequence homology between phospholipase and its inhibitor in snake venom. the primary structure of the inhibitor of vipoxin from the venom of the bulgarian viper (vipera ammodytes ammodytes, serpentes). | we are presenting the first primary structure of a snake venom inhibitor. it was isolated from the neurotoxin vipoxin of the bulgarian viper (vipera ammodytes ammodytes, serpentes) which represents a complex of a strong toxic basic protein with phospholipase a2 activity (2 isoenzymes) and the nontoxic acidic component functioning as its inhibitor. the sequence was established by automatic degradation in a liquid phase sequenator on the s-carboxymethylated chain and on the peptides obtained by tr ... | 1984 | 6489936 |
| calcium ion independent membrane leakage induced by phospholipase-like myotoxins. | the two snake venom myotoxins ammodytin l and myotoxin ii, purified respectively from vipera ammodytes ammodytes and bothrops asper, have phospholipase-like structures but lack an asp-49 in the active site and are without normal phospholipase activity. the interaction of these proteins with different types of liposomes indicated that the myotoxins were able to provoke rapid and extensive release of the aqueous content of liposomes. leakage was measured by two different methods: fluorescence dequ ... | 1992 | 1334427 |
| study of some physicochemical properties of the neurotoxic complex and its components from the venom of bulgarian sand viper, vipera ammodytes ammodytes. i. luminescence of tryptophan residues. | | 1979 | 34441 |
| ammodytin l is the main cardiotoxic component of the vipera ammodytes ammodytes venom. | venom of the nose-horned viper (v. a. ammodytes) as also venoms of some related european viperids can induce also cardiotoxic effects in mammals. in this work we demonstrated that the protein in the v. a. ammodytes venom acting on heart is a myotoxic secreted phospholipase a2analogue ammodytin l (atnl). in the isolated perfused rat heart atnl induced significant and irreversible cardiotoxicity characterized by atrioventricular (av) blockade. this venom protein induced appearance of high levels o ... | 2017 | 29030107 |
| disintegrins from the venom of vipera ammodytes ammodytes efficiently inhibit migration of breast cancer cells. | integrins are plasma membrane proteins, whose dysfunction frequently results in cancer pathology, and therefore they represent important targets of anti-tumour therapy. snake venoms are a rich source of disintegrins (dis), proteins that specifically bind integrins and thus interfere with their functions. in an attempt to discover new molecules for treatment of breast cancer, the major type of cancer in women, we isolated a dimeric dis (vaa-dis) from the venom of the nosehorned viper. by cell via ... | 2017 | 28862296 |
| cardiotoxic effects of the vipera ammodytes ammodytes venom fractions in the isolated perfused rat heart. | the nose-horned viper (vipera ammodytes ammodytes) is the most venomous european snake. its venom is known as haematotoxic, myotoxic and neurotoxic but it exerts also cardiotoxic effects. to further explore the cardiotoxicity of the venom we separated it into four fractions by gel filtration chromatography. three fractions that contain polypeptides (a, b, and c) were tested for their effects on isolated rat heart. heart rate (hr), incidence of arrhythmias (atrioventricular (av) blocks, ventricul ... | 2016 | 27623431 |
| a single dose of viperfav(tm) may be inadequate for vipera ammodytes snake bite: a case report and pharmacokinetic evaluation. | viperfav(tm) is a commercial f(ab')₂ antivenom prepared against european vipers venom. it is safe and effective for treating envenomation caused by vipera aspis and vipera berus. therapeutic efficacy for treating vipera ammodytes ammodytes (v. a. ammodytes) envenoming has not been yet described, although protective efficacy has been demonstrated in preclinical studies. we report on a 32-year-old man bitten by v. a. ammodytes who was treated with viperfav™. viperfav™ promptly reduced local extens ... | 2016 | 27548220 |
| venomics of vipera berus berus to explain differences in pathology elicited by vipera ammodytes ammodytes envenomation: therapeutic implications. | vipera berus berus (vbb) is the most widely distributed and vipera ammodytes ammodytes (vaa) the most venomous viper in europe. in particular areas of the old continent their toxic bites constitute a considerable public health problem. to make the current envenomation therapy more effective we have analysed the proteome of vbb venom and compared it with that of vaa. we found the proteome of vbb to be much less complex and to contain smaller levels of particularly snaclecs and spla2s. snaclecs ar ... | 2016 | 27327134 |
| [further studies on the fractionation and purification of the toxic components from the venom of the bulgarian viper (vipera ammodytes ammodytes)]. | | 1971 | 5106918 |
| [studies on the venom of the bulgarian viper (vipera ammodytes ammodytes). ii. changes in the venom following detoxication with formalin]. | | 1965 | 14254733 |