| [production of antiserum to neurotoxin-2 from naja naja oxiana cobra venom and reaction with the toxin]. | antiserum to neurotoxin-2 from the venom of the cobra was obtained by immunization of rabbits via the injection of the toxin into the lymphatic nodes and by two re-immunizations via the injection of the toxin into the blood and intramuscularly. using scores of micrograms of the toxin, specific antisera with high antibody titer were obtained. in spite of high specificity of separate stages of the reactions, using indirect immune fluorescence technique, no specific fluorescence was found in the en ... | 1979 | 92118 |
| [inhibition by heparin of the ganglionic-blocking and cardiotoxic effect of central asian cobra venom]. | | 1975 | 241428 |
| [analysis of disorders of the functional state of various sections of the central nervous system under the influence of central asian cobra venom]. | | 1975 | 1182237 |
| the active site and partial sequence of cobra venom acetylcholinesterase. | about 30% of the primary structure of acetylcholinesterase (ache) from the cobra naja naja oxiana has been determined. the sequence around the serine residue labeled by diisopropylfluorophosphate (dfp) was found to be tvtlfgesagaasvgm which is similar to the active sites of ache from other tissues. the part of the primary structure determined shows 76% identity with ache from torpedo and 42% identity with the drosophila enzyme. a surprisingly large identity (42% in the sequence determined) was f ... | 1990 | 2340076 |
| [modulation of the m-cholinergic reaction by the venom of the central asian cobra (naja naja oxiana)]. | the effect of the central asian cobra's (naja naja oxiana) poison upon cholinergic response of isolated small intestine was studied in the wistar rats. the effect involved a significant activation by 30-70 per cent of m-cholinergic response in the type of "noncompetitive" interaction. the modulating effect of the poison is supposed to occur due to changes in cytoplasmatic membrane. | 1988 | 3181518 |
| [use of naja oxiana venom for modulating the adrenergic process]. | specific changes of adrenergic responses to the poison of the middle asia cobra were found in the rat isolated small intestine. the changes reminded the action of inhibitors upon enzymes and may be characterized as a partial competitiveless interaction. the poison modulating effect upon adrenergic responses seem to be unrelated to its direct action on adrenoreceptors, but mediated through the effector cell's membrane. | 1987 | 3428434 |
| effect of pure venom phospholipase a2 from the central asian cobra (naja naja oxiana eichwald) on oxidative functions of rat liver mitochondria. | | 1985 | 4077115 |
| [the effect of the venom on the central asian cobra naja naja oxiana on tyrosine-c-14 incorporation in the cellular structures of mouse liver]. | | 1974 | 4462296 |
| [antiradiation effect of a cytotoxin, venom of the central asian cobra, and aspects of the mechanism of its action]. | | 1981 | 7323284 |
| characterization of monoclonal antibodies against naja naja oxiana neurotoxin i. | seven monoclonal antibodies (mabs) were developed against neurotoxin i (nt-1), a protein from central asian cobra (naja naja oxiana) venom which binds specifically to nicotinic acetylcholine receptor (achr). all of the mabs cross-reacted with another long-chain post-synaptic neurotoxin, bungarus multicinctus alpha-bungarotoxin (alpha-bt), but not naja naja kaouthia alpha-cobratoxin, in an enzyme-linked immunosorbent assay (e.l.i.s.a.). short-chain post-synaptic neurotoxins like naja naja atra co ... | 1994 | 7945236 |
| both neurotoxin ii from venom of naja naja oxiana and its endogenous analogue induce apoptosis in tumor cells. | both neurotoxin ii (nt ii from venom of naja naja oxiana) and 20-30 kda proteins partially purified from pig brain (ntlm) cross-reacting with antibodies to nt ii were cytotoxic for l929 and k562 tumor cells at concentrations of 10(-6)-10(-8) m. modification of cys residues significantly reduced cytotoxicity of nt ii. both nt2 and ntlm induced apoptosis in l929 and k562 cells. | 1994 | 8119402 |
| functional properties of human factor va lacking the asp683-arg709 domain of the heavy chain. | a protease purified from the venom of the elapid snake naja naja oxiana converts human blood coagulation factor va into a molecule (factor vano) with greatly reduced cofactor activity. polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate revealed that the venom protease cleaved a small peptide from the heavy chain of factor va and reduced the apparent m(r) from 105,000 to 101,000. this peptide was isolated by high performance liquid chromatography on a reversed-phase colu ... | 1994 | 8051166 |
| [effect of phospholipase a2 from naja naja oxiana venom on activity of na+,k+-atpase isoenzymes in rat brain]. | the specific sensitivity of the isoforms of the rat brain na+,k(+)-atpase catalytic subunit to phospholipase a2 (pl a2) from naja naja oxiana venom has been estimated on the basis of changes in the two-component dose response curve of ouabain inhibition of na+,k(+)-atpase activity. moderate na+,k(+)-atpase inactivation of pl a2 is accompanied by a decrease of the apparent affinity for ouabain in comparison with the untreated enzyme without any significant changes in the isoform activity ratio in ... | 1996 | 9011252 |
| [the characteristics of the binding of m-cholinergic blockers and beta-adrenoblockers by the brain synaptosomes of 15-day-old and adult rats]. | significant difference in values of basic parameters, bmax and kd which characterize binding of 3h-quinuclidynylbenzylate and 3h-dihydroalprenolol, specific blockers of m-cholino- and beta-adrenoreceptors, has been established for brain synaptosomes from 15-day and adult rats. it was shown that phospholipase a2 (1 microgram/ml), a membrane active component from the venom of the cobra naja naja oxiana, reduced bmax and kd for binding 3h-quinuclidynylbenzylate and 3h-dihydroalprenolol by synaptoso ... | 1994 | 7863744 |
| [reactions between 3h-monoacetylcobratoxin and membrane preparations from denervated muscles and caudate nuclei]. | 3h-monoacetyl derivative of the major neurotoxin of venom obtained from naja naja oxiana was used as a marker of the nicotinic cholinoreceptor (n-chr). it was shown that binding of neurotoxin with the membranes of bovine caudate nuclei unlike binding with the membranes of the rabbit gastrocnemius muscles is less strong and cannot be blocked completely with high concentrations of neurotoxin and d-tubocurarine. serum of the rabbits immmunized with the protein preparation isolated from the membrane ... | 1980 | 7397340 |
| [effect of phospholipase a2 from the venoms of bee and middle asian cobra on choline uptake by synaptosomes]. | the effect of purified phospholipase a2 from venom of the bee apis mellifica and from venom of the cobra naja naja oxiana on the na+-dependent high affinity choline transport into the synaptosomes of rabbit corpus striatum (active uptake) was studied. both phospholipases a2 were shown to inhibit the active choline uptake by the synaptosomes. the bee venom phospholipase at a concentration of 10(-8) m and the cobra venom phospholipase at a concentration of 10(-6) m produced a 50% inhibition of cho ... | 1981 | 7295818 |
| the trna-like structure at the 3' terminus of turnip yellow mosaic virus rna. differences and similarities with canonical trna. | the 3' terminus of tymv rna, which possesses trna-like properties, has been studied. a 3' terminal fragment of 112 nucleotides was obtained by cleavage with rnase h after hybridization of a synthetic oligodeoxynucleotide to the viral rna. the accessibility of cytidine and adenosine residues was probed with chemical modification. enzymatic digestion studies were performed with rnase t1, nuclease s1 and the double-strand specific rnase from the venom of the cobra naja naja oxiana. a model is propo ... | 1982 | 7079175 |
| mapping trna structure in solution using double-strand-specific ribonuclease v1 from cobra venom. | a method for mapping all base-paired stems in both elongation and initiator trnas is described using double-stranded-specific ribonuclease v1 from the venom of the cobra naja naja oxiana. 32p-end-labeled rna is first partially digested with double-strand-specific v1 nuclease under near physiological conditions, and the resultant fragments are than electrophoretically fractionated by size in adjacent lanes of a polyacrylamide gel run in 90% formamide. after autoradiography, the base-paired nucleo ... | 1981 | 7031604 |
| the secondary structure of the protein l1 binding region of ribosomal 23s rna. homologies with putative secondary structures of the l11 mrna and of a region of mitochondrial 16s rrna. | an heterologous complex was formed between e. coli protein l1 and p. vulgaris 23s rna. we determined the primary structure of the rna region which remained associated with protein l1 after rnase digestion of this complex. we also identified the loci of this rna region which are highly susceptible to t1, s1 and naja oxiana nuclease digestions respectively. by comparison of these results with those previously obtained with the homologous regions of e. coli and b. stearothermophilus 23s rnas, we po ... | 1981 | 7010313 |
| comparison of the hydrolysis patterns of several trnas by cobra venom ribonuclease in different steps of the aminoacylation reaction. | the hydrolysis of several trnas by an endonuclease extracted from the venom of naja oxiana and specific for double-stranded, or at least highly ordered, regions has been studied under various experimental conditions. it is shown that the hydrolysis patterns of yeast trnaphe, trnaval and trnaasp in the isolated state are similar, most of the cuts occurring in the anticodon and acceptor stems. ionic conditions are able to modify the hydrolysis pattern. the origin of these modifications is discusse ... | 1982 | 6915854 |
| effect of membrane active components from the venom of central asian cobra (naja naja oxiana eichwald) on some functional parameters of mitochondria. | | 1983 | 6671676 |
| [a new low molecular-weight protein effector of human complement from the venom of the central asian cobra naja naja oxiana]. | six protein effectors of human complement were isolated from the whole venom of the central asian cobra naja naja oxiana. three of them have acidic properties and molecular weights of 61 000, 5000 and 3000, and the rest are basic proteins with molecular weights of 54 000, 9000 and 7000. two low molecular weight basic proteins cfb-ii and cfb-iii are isolated in as high amounts as 115 and 85 mg per g of dry venom. all the effectors inhibit the classical pathway of complement activation and, with t ... | 1984 | 6567467 |
| effect of ca2+ on the action of cobra (naja naja oxiana eichwald) venom components on mitochondrial enzyme systems. | | 1984 | 6526419 |
| joint action of membrane-active components from central asian cobra (naja naja oxiana eichwald) venom on rat liver mitochondrial functions. | | 1984 | 6490077 |
| location of single-stranded and double-stranded regions in rat liver ribosomal 5s rna and 5.8s rna. | rat liver 5s rrna and 5.8s rrna were end-labelled with 32p at 5'-end or 3'-end of the polynucleotide chain and partially digested with single-strand specific s1 nuclease and double-strand specific endonuclease from the cobra naja naja oxiana venom. the parallel use of these two structure-specific enzymes in combination with rapid sequencing technique allowed the exact localization of single-stranded and double-stranded regions in 5s rna and 5.8 s rna. the most accessible regions to s1 nuclease i ... | 1981 | 6272219 |
| higher-order structure in the 3'-terminal domain vi of the 23 s ribosomal rnas from escherichia coli and bacillus stearothermophilus. | an experimental approach was used to determine, and compare, the higher-order structure within domain vi of the 23 s ribosomal rnas from escherichia coli and bacillus stearothermophilus. this domain, which encompasses approximately 300 nucleotides at the 3' end of the rnas, consists of two large subdomains. the 5' subdomain has been conserved during evolution and appears to be functionally important for the binding of the ef-1 x gtp x aminoacyl-trna complex in eukaryotes. the 3' subdomain has di ... | 1984 | 6209406 |
| higher order structure in the 3'-minor domain of small subunit ribosomal rnas from a gram negative bacterium, a gram positive bacterium and a eukaryote. | an experimental approach was used to determine and compare the highest order structure within the 150 to 200 nucleotides at the 3'-ends of the rnas from the small ribosomal subunits of escherichia coli, bacillus stearothermophilus and saccharomyces cerevisiae. chemical reagents were employed to establish the degree of stacking and/or accessibility of each adenosine, guanosine and cytidine. the double helices were probed with a cobra venom ribonuclease from naja naja oxiana, and the relatively un ... | 1983 | 6194304 |
| primary and secondary structures of escherichia coli mre 600 23s ribosomal rna. comparison with models of secondary structure for maize chloroplast 23s rrna and for large portions of mouse and human 16s mitochondrial rrnas. | we determined 90% of the primary structure of e.coli mre 600 23s rrna by applying the sequencing gel technique to products of t1, s1, a and naja oxiana nuclease digestion. eight cistron heterogeneities were detected, as well as 16 differences with the published sequence of a 23s rrna gene of an e.coli k12 strain. the positions of 13 post-transcriptionally modified nucleotides and of single-stranded, double-stranded and subunit surface regions of e.coli 23s rrna were identified. using these exper ... | 1981 | 6170936 |
| monoclonal antibody immunoaffinity chromatography of the nerve growth factor from snake venoms. | 1. pure monoclonal antibodies to vipera lebetina venom nerve growth factor have been isolated by affinity chromatography using cnbr-agarose bound antigen. 2. nerve growth factors from ten snake venoms (vipera lebetina, vipera russellii, vipera berus berus, vipera ursini, echis carinatus, agkistrodon halys, bungarus caeruleus, naja naja oxiana, naja naja, naja naja atra) were purified using monoclonal antibodies against ngf linked to brcn-activated agarose. | 2013 | 3621902 |
| [biospecific adsorption chromatography of phospholipase a2 from different sources]. | methods of biospecific adsorption chromatography of phospholipase a2 obtained from porcine pancreas and naja naja oxiana, vipera ursini renardi, vespa orientalis venoms were developed. granulated polyamide with covalently linked phosphatidylethanolamine were used as an affinity adsorbent. chemical inertness of linked phosphatidylethanolamine to the hydrolytic action of phospholipase a2 and its high affinity for biospecific complexes are shown. forms of phospholipase a2 different in their affinit ... | 1985 | 3991479 |
| [a factor from the venom of the central asiatic cobra naja naja oxiana, which inactivates component c4 of human complement]. | an acid glycoprotein (mol. m. 60 kda) containing 6 sialic acid residues and n-terminal thr was isolated from the venom of the central asian cobra naja naja oxiana. the protein has an anticomplementary activity selectively inactivating of the c4 component of the human complement. this factor (cfa-ib) binds c4 with ki = 0.27 +/- 0.13 microm and then irreversible inactivates it with a rate constant k = 0.75 +/- 0.25 min-1. membrane bound c4b restores its ability of cfa-ib binding. this binding hind ... | 1989 | 2770721 |
| interactions of pla2-s from vipera lebetina, vipera berus berus and naja naja oxiana venom with platelets, bacterial and cancer cells. | secretory phospholipasesa(2) (spla(2)s) form a large family of structurally related enzymes widespread in nature. herein, we studied the inhibitory effects of spla(2)s from vipera lebetina (vlpla(2)), vipera berus berus (vbbpla(2)), and naja naja oxiana (nnopla(2)) venoms on (i) human platelets, (ii) four different bacterial strains (gram-negative escherichia coli and vibrio fischeri; gram-positive staphylococcus aureus and bacillus subtilis) and (iii) five types of cancer cells (pc-3, lncap, mc ... | 2013 | 23348053 |
| monoclonal antibodies against vipera lebetina venom nerve growth factor cross-react with other snake venom nerve growth factors. | nerve growth factor (ngf) was isolated from the venom of vipera lebetina and was purified to homogeneity as judged by sds gel electrophoresis. the biologically active ngf was used to immunize balb/c mouse, and the spleen cells from immunized mouse were fused with mouse pai myeloma cells. forty-seven hybrid cell lines, secreting monoclonal antibodies to v. lebetina ngf, were isolated and nine of them purified from ascitic fluids. the isolated antibodies define two partially overlapping epitopes o ... | 1987 | 2448608 |
| [the effect of calmodulin and chlorpromazine on the activity of phospholipases a2 from various sources]. | the effects of calmodulin and chlorpromazine on purified phospholipase a2 preparations from snake venoms: cobra (naja naja oxiana), echis (ehis multisquamatus) and agkistrodon halys halys, as well as on phospholipases a2 from rat liver mitochondria and human platelets were studied. it was shown that within the concentration range of 1-5 microm calmodulin stimulates the phospholipase activity. chlorpromazine inhibits the activity of these enzymes, the degree of inhibition being different for vari ... | 1990 | 2344456 |
| activation of bovine factor v by an activator purified from the venom of naja naja oxiana. | the crude venom of many elapid snakes appeared to contain proteins that activated blood coagulation factor v. the factor v activator present in the venom of naja naja oxiana was purified to homogeneity by chromatography on a mono-s column. the activator was a single chain protein with an apparent mol. wt of 48,000, as judged by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and by gel permeation chromatography on sephacryl s200. activation of bovine factor v by the ... | 1992 | 1440644 |
| toxicities, ld50 prediction and in vivo neutralisation of some elapid and viperid venoms. | toxicity levels of elapid (naja naja and naja oxiana) viperid (vipera lebetina and vipera russelli) venoms for mice and rat for intraperitoneal intravenous and intramuscular routes have been determined. the data have been analysed using a mathematical expression to calculate lethal venom concentrations in human snake bite cases. further, in vivo neutralisation of snake venom potency (after experimental injection) using high voltage-low current electric shock treatment has been attempted. this tr ... | 1992 | 1294479 |
| [comparative study of the immunogenicity of various forms of naja oxiana cardiotoxin]. | comparative study of the immune sera from rabbits immunized with both formol and native cardiotoxins, cardiotoxin incorporated into sphingomyelin-phosphatidylcholine-cholesterol liposome stabilized with osmium tetroxide, and a cardiotoxin-succinylated bovine albumin conjugate was performed. the latter produced antibodies identified by immunodiffusion assay. the highest survival was observed in animals treated with antiserum to cardiotoxin-albumin conjugate, followed by antitoxin to combination o ... | 1996 | 8755106 |
| antibody-mediated neutralization and binding-reversal studies on alpha-neurotoxins from micrurus nigrocinctus nigrocinctus (coral snake) venom. | an elisa based, non-radioactive acetylcholine receptor (achr) binding assay was used to detect the alpha-neurotoxins present in micrurus nigrocinctus nigrocinctus venom. sera from horses hyperimmunized against m. nigrocinctus venom contain antibodies which inhibit the binding of m. n. nigrocinctus alpha-neurotoxins to achr and reverse the binding of toxins already complexed with the receptor. this result supports the importance of using antivenom therapeutically in m. n. nigrocinctus envenomatio ... | 1996 | 8730930 |
| acetylcholine receptor binding characteristics of snake and cone snail venom postsynaptic neurotoxins: further studies with a non-radioactive assay. | the binding of postsynaptic neurotoxins from snake and marine cone snail (conus sp.) venoms to nicotinic acetylcholine receptor (achr) was investigated with an elisa-based, non-radioactive assay. three snake postsynaptic toxins from the long-chain group (naja naja kaouthia cobratoxin, naja oxiana neurotoxin i, bungarus multicinctus alpha-bungarotoxin) and short-chain group (naja naja atra cobrotoxin, naja oxiana neurotoxin ii, and laticauda semifasciata erabutoxin b) were studied. both types of ... | 1993 | 8212028 |
| "weak toxin" from naja kaouthia is a nontoxic antagonist of alpha 7 and muscle-type nicotinic acetylcholine receptors. | a novel "weak toxin" (wtx) from naja kaouthia snake venom competes with [(125)i]alpha-bungarotoxin for binding to the membrane-bound torpedo californica acetylcholine receptor (achr), with an ic(50) of approximately 2.2 microm. in this respect, it is approximately 300 times less potent than neurotoxin ii from naja oxiana and alpha-cobratoxin from n. kaouthia, representing short-type and long-type alpha-neurotoxins, respectively. wtx and alpha-cobratoxin displaced [(125)i]alpha-bungarotoxin from ... | 2001 | 11279130 |
| [expression of neurotoxin ii from naja oxiana cobra venom in escherichia coli in a hybrid form with thioredoxin]. | neurotoxin ii from the venom of cobra naja oxiana is a short type alpha-neurotoxin, which competitively inhibits nicotinic acetylcholine receptor. the toxin gene was expressed as a construct fused with the thioredoxin gene and the linker encoding the enteropeptidase recognition site and a met residue between the genes. the fusion protein was mainly cleaved by cyanogen bromide, since enteropeptidase was less effective. the yield of neurotoxin ii was 6 mg/l of the bacterial culture. the resulting ... | 2004 | 15040301 |
| comparative study of structure and activity of cytotoxins from venom of the cobras naja oxiana, naja kaouthia, and naja haje. | cytotoxins are positively charged polypeptides that constitute about 60% of all proteins in cobra venom; they have a wide spectrum of biological activities. by cd spectroscopy, cytotoxins ct1 and ct2 naja oxiana, ct3 naja kaouthia, and ct1 and ct2 naja haje were shown to have similar secondary structure in an aqueous environment, with dominating beta-sheet structure, and to vary in the twisting angle of the beta-sheet and the conformation of disulfide groups. using dodecylphosphocholine micelles ... | 2004 | 15527416 |
| oxiagin from the naja oxiana cobra venom is the first reprolysin inhibiting the classical pathway of complement. | a basic glycoprotein oxiagin with molecular mass of 49.8 kda was isolated from the venom of central asian cobra naja oxiana. partial amino acid sequence determination has shown that oxiagin belongs to reprolysins, a subfamily of animal metalloproteinases possessing a characteristic multidomain structure. oxiagin was found to inhibit the classical pathway of the complement system. a study of the oxiagin influence on the different stages of the classical pathway showed that it inhibited the format ... | 2005 | 15829304 |
| cancer cell injury by cytotoxins from cobra venom is mediated through lysosomal damage. | cytotoxins from cobra venom are known to manifest cytotoxicity in various cell types. it is widely accepted that the plasma membrane is a target of cytotoxins, but the mechanism of their action remains obscure. using the confocal spectral imaging technique, we show for the first time that cytotoxins from cobra venom penetrate readily into living cancer cells and accumulate markedly in lysosomes. cytotoxins ct1 and ct2 from naja oxiana, ct3 from naja kaouthia and ct1 from naja haje are demonstrat ... | 2005 | 15847607 |
| polyclonal antibodies against native weak toxin naja kaouthia discriminate native weak toxins and some other three-fingered toxins against their denaturated forms. | polyclonal antibodies obtained by immunization of rabbits with native form of weak toxin (wtx) from cobra naja kaouthia venom efficiently interacted with wtx and a weak toxin from naja oxiana venom, but not so with their denaturated forms. these antibodies could also bind with lower affinity other groups of three-fingered toxins: long-chain alpha-neurotoxins, muscarinic toxins and cytotoxins, but practically did not bind short-chain alpha-neurotoxins. the efficiency of toxin-antibody interaction ... | 2005 | 15925395 |
| a model for short alpha-neurotoxin bound to nicotinic acetylcholine receptor from torpedo californica: comparison with long-chain alpha-neurotoxins and alpha-conotoxins. | short-chain alpha-neurotoxins from snakes are highly selective antagonists of the muscle-type nicotinic acetylcholine receptors (nachr). although their spatial structures are known and abundant information on topology of binding to nachr is obtained by labeling and mutagenesis studies, the accurate structure of the complex is not yet known. here, we present a model for a short alpha-neurotoxin, neurotoxin ii from naja oxiana (ntii), bound to torpedo californica nachr. it was built by comparative ... | 2005 | 16290328 |
| the trna-like structure of turnip yellow mosaic virus rna: structural organization of the last 159 nucleotides from the 3' oh terminus. | the secondary structure of the isolated trna-like sequence (n=159) present at the 3' oh terminus of turnip yellow mosaic virus rna has been established from partial nuclease digestion with s1 nuclease and t1, cl(3), and naja oxiana rnases. the fragment folds into a 6-armed structure with two main domains. the first domain, of loose structure and nearest the 5' oh terminus, is composed of one large arm which extends into the coat protein cistron. the second, more compact domain, is composed of th ... | 1982 | 16453415 |
| protective action of snake venom naja naja oxiana at spinal cord hemisection. | based on data accumulated regarding the neuroprotective action of proline-rich-peptide-1 (prp-1, a fragment of neurophysin vasopressin associated hypothalamic glycoprotein consisting of 15 amino acid residues) on neurons survival and axons regeneration and taking into the account that lvv-hemorphin-7 (lvv-h7, an opioid peptide, widely distributed in different cell types of various tissues of intact rats, including those of the nervous and immune systems) derived from the proteolytic processing o ... | 2007 | 17451057 |
| bacterial expression, nmr, and electrophysiology analysis of chimeric short/long-chain alpha-neurotoxins acting on neuronal nicotinic receptors. | different snake venom neurotoxins block distinct subtypes of nicotinic acetylcholine receptors (nachr). short-chain alpha-neurotoxins preferentially inhibit muscle-type nachrs, whereas long-chain alpha-neurotoxins block both muscle-type and alpha7 homooligomeric neuronal nachrs. an additional disulfide in the central loop of alpha- and kappa-neurotoxins is essential for their action on the alpha7 and alpha3beta2 nachrs, respectively. design of novel toxins may help to better understand their sub ... | 2007 | 17576769 |
| l-amino acid oxidase from naja naja oxiana venom. | a new l-amino acid oxidase (laao) was isolated from the central asian cobra naja naja oxiana venom by size exclusion, ion exchange and hydrophobic chromatography. the n-terminal sequence and the internal peptide sequences share high similarity with other snake venom l-amino acid oxidases, especially with those isolated from elapid venoms. the enzyme is stable at low temperatures (-20 degrees c, -70 degrees c) and loses its activity by heating at 70 degrees c. specific substrates for the isolated ... | 2008 | 18294891 |
| cytotoxic activity of acetylcholine receptor ligands. | acetylcholine receptor ligands were studied for cytotoxicity in k562 human erythroid leukemia tumor cells. cytotoxicity of carbachol, an agonist of acetylcholine receptors, atropine, an antagonist of muscarinic acetylcholine receptor, neurotoxin 11 (nt ii) from naja naja oxiana cobra venom and tubocurarine, antagonists of acetylcholine receptor of nicotinic type was exhibited in the 10-7-10-5 m concentration range. several cytolytic processes, two for carbachol and three for other ligands, corre ... | 1997 | 19856291 |
| bacterial production and refolding from inclusion bodies of a "weak" toxin, a disulfide rich protein. | the gene for the "weak" toxin of naja kaouthia venom was expressed in escherichia coli. "weak" toxin is a specific inhibitor of nicotine acetylcholine receptor, but mechanisms of interaction of similar neurotoxins with receptors are still unknown. systems previously elaborated for neurotoxin ii from venom of the cobra naja oxiana were tested for bacterial production of "weak" toxin from n. kaouthia venom. constructs were designed for cytoplasmic production of n. kaouthia "weak" toxin in the form ... | 2009 | 19916927 |
| investigation of ligand-binding sites of the acetylcholine receptor using photoactivatable derivatives of neurotoxin ii from naja naja oxiana. | several photoaffinity derivatives of neurotoxin ii from the venom of the central asian cobra naja naja oxiana have been prepared. after reaction of the 125i-labeled derivatives with the nicotinic acetylcholine receptor from electric organ, the alpha-subunit of the nachr is almost exclusively labeled by the derivative carrying the photoactivatable group in position lys46. in contrast to this, a reactive group at lys26 predominantly labels the gamma- and delta-subunits, while the alpha- and beta-s ... | 2006 | 1525162 |
| mechanism of platelet effects of cardiotoxins from naja nigricollis crawshawii (spitting cobra) snake venom. | four cardiotoxins isolated from naja nigricollis crawshawii venom show inhibition of platelet aggregation when tested on whole blood aggregation in an electronic aggregometer. a similar inhibitory effect is observed by adding hemolyzed erythrocytes to whole blood before initiation of aggregation with collagen. qualitatively, adp-induced aggregation in whole blood appears to be different from collagen-induced aggregation in that the change in impedance is smaller than that induced by collagen. th ... | 2011 | 3194895 |
| [isolation of highly purified ribonuclease from cobra (naja oxiana) venom]. | dialysis, gel-chromatography on sephadex g-75 (superfine) and chromatography on sulphoethylcellulose give high yield (68 per cent) of 162-fold purified ribonuclease from cobra venom. in ion-exchange chromatography, ribonuclease is eluted in two fractions. the fraction with the highest specific activity has a molecular weight of 15900 and is homogeneous in 15 per cent polyacrilamide gel electrophoresis at ph 8.9. electrophoresis at ph 4.3 reveals a minor fast component of this fraction which also ... | 1995 | 173425 |
| [studies of complex lipids. synthesis of ionophore derivatives of diphosphatidylglycerol (cardiolipin)]. | synthesis of cardiolipin analogues containing an ionophore residue in the fatty acid moiety is described. the ionophore, dibenzo-18-crown-6, has been incorporated into second position of the glycerol residue by acylating mono- and dilysocardiolipin with a modified fatty acid anhydride. lyso-derivatives of cardiolipin have been prepared by enzymatic hydrolysis of beef heart cardiolipin by snake venom phospholipase a2 (naja naja oxiana). | 2011 | 3219123 |
| use of some snake venoms in the diagnostics of paroxysmal nocturnal hemoglobinuria (pnh). | the crude toxin of agkistrodon piscivorus was found to produce hemolysis of pnh erythrocytes by way of complement activation, however the degree of pnh blood cell lysis was lower than in other techniques used. the crude toxins of naja naja and naja oxiana cause much higher hemolysis though lower hemolysis takes place in normal blood cells. in some normal persons and different blood diseases it is responsible for high hemolysis even when the complement is absent. from naja naja toxin a fraction c ... | 1985 | 2410338 |
| [complement and noncomplement hemolysis of blood cells in patients with various blood diseases after the administration of the crude toxins of agkistrodon piscivorus, naja naja, naja oxiana]. | | 1984 | 6515308 |
| the influence of cytotoxins from central asian cobra venom and melittin from bee venom on the thermodynamic properties of phospholipid bilayer. | the interaction of cytotoxin vc1 and vc5 from central asian cobra and melittin from the bee venom with multilayer liposomes prepared from dimiristoylphosphatidylcholine with an addition of phosphatidic acid have been studied by the method of differential scanning calorimetry. incorporation of vc1, vc5 and melittin into the lipid resulted in pronounced changes in the thermodynamic properties of the lipid. polypeptides studied induced lateral phase separation in the lipid. interaction between mole ... | 1987 | 3666427 |
| antibacterial activity of isolated immunodominant proteins of naja naja (oxiana) venom. | the aim of this study is to investigate antibacterial effects of immunodominant proteins isolated from the venom of naja naja oxiana snake against staphylococcus aureus, escherichia coli, bacillus subtilis and pseudomonas aeruginosa. the innate immune system is an important line of defense against bacterial diseases. antibacterial peptides and proteins produced by snake venoms have recently attracted significant attention due to their relevance to bacterial diseases and the potential of being co ... | 2017 | 28496483 |
| [complement-inhibiting acidic factors from the venom of central asian cobra naja naja oxiana]. | two anticomplementic factors isolated from the venom of the central asian cobra naja naja oxiana by chromatography on deae-sepharose cl-6b and subsequent gel filtration on sephacryl s-200 were studied. of these, five factors (cfa-ia, cfa-ib, cfa-ic, cfa-iia and cfa-iib), cfa-ib had been characterized earlier, while cfa-ia was assigned to a previously identified h-cof factor. it was shown that cfa-ic has a molecular mass of 3900 da; its content in the venom amounts to 2.6 mg/g of dry venom. this ... | 1989 | 2633805 |
| variation in yield and lethality of venoms from iranian snakes. | the dangerous venomous terrestrial snakes of iran belong to three groups: the elapidae (cobras); the viperinae (true vipers); the crotalinae (pit vipers). geographical distribution of each species was determined. studies on the venoms extracted from the following iranian snakes, oxus cobra, naja naja oxiana, levantine viper (afyi), vipera lebetina, carpet viper, echis carinatus, persian horned viper, pseudocerastes persicus, latifii viper, vipera latifii, mountain viper, vipera xanthina and cauc ... | 1984 | 6474490 |
| factor v activation and inactivation by venom proteases. | blood coagulation factor v is a single-chain glycoprotein with m(r) = 330,000 which plays an important role in the procoagulant and anticoagulant pathways. thrombin activates factor v into factor va, a two-chain molecule which is composed of a heavy (m(r) = 105,000) and a light chain (m(r) = 71,000/74,000). factor va accelerates factor xa-catalysed prothrombin activation more than 1,000-fold and under physiological conditions the cofactor activity of factor va in prothrombin activation is down-r ... | 2017 | 11910191 |
| ten years of snakebites in iran. | many species of venomous snakes are found in iran. the most medically important species which are responsible for the most snakebite incidents in iran belong to the viperidae family, including vipera lebetina, echis carinatus, pseudocerastes persicus, vipera albicornuta and the elapidae family, especially naja naja oxiana. at least one kind of venomous snake is found in each of the 31 provinces, and many provinces have more than one venomous species. as a result, snakebite is a considerable heal ... | 2014 | 25193748 |
| cross neutralization of dangerous snake venoms from africa and the middle east using the vacsera polyvalent antivenom. egyptian organization for biological products & vaccines. | this study was performed to assess the ability of polyvalent snake venom anti-serum, produced by the egyptian organization for biological products & vaccines (vacsera), to neutralize several toxic activities of snake venoms, not only of those included in the antivenom mixture, but also some additional venoms of snakes from egyptian, african, and middle eastern habitats. in general, the results revealed that polyvalent snake venom anti-serum from vacsera is highly effective in neutralizing egypti ... | 2002 | 12503876 |
| procoagulant activities in venoms from central asian snakes. | the venoms from central asian snakes (echis carinatus, echis multisquamatus, vipera ursini, vipera lebetina, agkistrodon halys halys and naja naja oxiana) contain several enzymes with amidolytic- and procoagulant activity. we have characterized the activities and the mol. wts of the venom enzymes that are able to convert a number of commercially available chromogenic substrates for activated coagulation factors. the chromogenic substrate cleavage patterns obtained for the crude venoms may be hel ... | 1991 | 1830705 |
| immunological properties of antivenins. ii. univalent naja haje antivenin. | a purified naja haje antivenin was tested against egyptian n. haje and n. nigricollis venoms, indian n. naja venom, iranian n. naja oxiana, vipera lebetina, and v. persica venoms, and echis carinatus venom from both iran and egypt. the different elapid venoms, with the exception of that of n. naja oxiana, showed a considerable number of identical and similar precipitin components by immunodiffusion and immunoelectrophoresis. on the other hand, only a few identical and partially identical lines w ... | 1976 | 816220 |
| [stages of the development of the embryos of snakes by the time of oviposition]. | embryos of 6 species of snakes--ptyas mucosus (l.), elaphe dione (pall.), psammophis lineolatum (brandt), natrix tesselata (laur), naja oxiana (eichw.), vipera lebetina turanica (cernov) and v. l. obtusa--at the stage of egg laying are described morphologically. different species of snakes are shown to lay the eggs containing embryos of different degrees of maturation. this series of transitions at the embryonic age (up to the time of egg viviparity) is connected with ecological peculiarities of ... | 1976 | 1037475 |
| [fibrinogen/fibrin-specific enzymes from copperhead (agkistrodon halys halys) and cobra (naja oxiana eichwald) snake venoms]. | ability of fractions of cobra's (naja oxiana eichwald) and copperhead snake's (agkistrodon halys halys) venoms to hydrolyze fibrinogen/fibrin was studied. in cobra's snake a component with molecular mass of nearly 60 kda was found to hydrolyze a-chain of fibrinogen but failed to hydrolyze casein/azocasein and fibrin. a fibrinogen-specific metalloproteinase, the enzyme was inhibited by edta. cobra's venom reduced the mass of donor's fresh blood clots. the copperhead snake's venom and the fraction ... | 2016 | 27420616 |
| [1h-nmr study of the naja naja oxiana neurotoxin ii and its spin-labeled derivatives. conformation of "short" neurotoxins]. | in 1h nmr spectra of neurotoxin ii n. n. oxiana the chemical shift ph-dependences in h2o and 2h2o solutions were studied, and also the deuterium exchange rates and chemical shift temperature gradients were measured for the amide protons. the spin probe method was applied to assess the degree of exposure into solvent of the amide and side chain protons. with the purpose of establishing mutual disposition of certain neurotoxin ii groupings, nuclear overhauser effect was studied in the 1h nmr spect ... | 1983 | 6679788 |
| the 1h nuclear-magnetic-resonance spectra of neurotoxin i and cardiotoxin vii4 from naja mossambica mossambica. | two toxins from the venom of naja mossambica mossambica, neurotoxin i and cardiotoxin vii4, were investigated in aqueous solution by high-resolution 1h nuclear magnetic resonance (nmr) techniques at 360 mhz. the spectral characterization of the proteins included determination of the number of slowly exchanging amide protons which can be observed in 2h2o solution, measurement of the amide proton chemical shifts and exchange rates, characterization of the aromatic spin systems and the internal mob ... | 1978 | 33043 |
| heart place and tail length evaluation in naja oxiana, macrovipera lebetina, and montivipera latifii. | to evaluate a) heart place and tail length, b) their correlations with other biometrics, c) sexual differences in those features, in regard to cardiovascular system in a number of snakes from iran, about which there is little information. | 2014 | 25312108 |
| cardiotoxins: functional role of local conformational changes. | cardiotoxins (cts) from snake venoms are a family of homologous highly basic proteins that have extended hydrophobic patterns on their molecular surfaces. cts are folded into three β-structured loops stabilized by four disulfide bridges. being well-structured in aqueous solution, most of these proteins are membrane-active, although the exact molecular mechanisms of ct-induced cell damage are still poorly understood. to elucidate the structure-function relationships in cts, a detailed knowledge o ... | 2017 | 29053272 |
| [interaction of cardiotoxin a5 with a membrane: role of conformational heterogeneity and hydrophilic properties]. | the hypothesis that local conformational differences of snake venom cardiotoxins (cytotoxins, cts) may play a significant role in their interaction with membrane was tested by molecular modeling of the behavior of the ct a5 from the venom of naja atra in water and at the water-membrane interface. two models of the ct a5 spatial structure are known: the first was obtained by x-ray analysis and the second, by nmr studies in solution. a molecular dynamics (md) analysis demonstrated that loop ii of ... | 2017 | 14743531 |
| [major complement inhibiting factors from the venom of the central asian cobra naja naja oxiana]. | the properties of two anticomplementic factors isolated by cm-sepharose chromatography from the basic non-adsorbed on deae-sepharose fraction of the central asian cobra naja naja oxiana venom, were studied. of these three factors (cfb-i, cfb-ii and cfb-iii) the latter had been characterized earlier. cfb-i was shown to be a protein with an n-terminal asp and a molecular mass of about 39 kda (data from gel chromatography); its content in the venom is 3.6 mg/g of dry venom. the protein inhibits mai ... | 1989 | 2627558 |
| anionic lipids: determinants of binding cytotoxins from snake venom on the surface of cell membranes. | the cytotoxic properties of cytotoxins (cts) from snake venom are mediated by their interaction with the cell membrane. the hydrophobic pattern containing the tips of loops i-iii and flanked by polar residues is known to be a membrane-binding motif of cts. however, this is not enough to explain the difference in activity among various cts which are similar in sequence and in 3d structure. the mechanism of further ct-membrane interaction leading to pore formation and cell death still remains unkn ... | 2010 | 22649646 |
| photochemically induced nuclear polarization study of exposed tyrosines, tryptophans, and histidines in postsynaptic neurotoxins and in membranotoxins of elapid and hydrophid snake venoms. | the accessibility of surface tyrosines, histidines, and tryptophans in snake venom neurotoxins (short and long) and in membranotoxins to excited triplet 10-(carboxyethyl)-flavin was studied by photochemically induced dynamic nuclear polarization at 270 mhz. trp-29 is accessible in the short neurotoxins--erabutoxins a, b, and c and cobrotoxin--and also in the long neurotoxins--alpha-cobratoxin and alpha-bungarotoxin. tyr-25 is practically inaccessible in all neurotoxins. tyr-39 in cobrotoxin and ... | 1984 | 6498168 |
| the 1h nuclear-magnetic-resonance spectra and spatial structure of the naja mossambica mossambica neurotoxin iii. | the proton nmr spectra at 300 mhz of neurotoxin iii from venom of naja mossambica mossambica are reported. by the use of double resonance techniques, ph dependence chemical shifts, isotope labeling technique, and comparison with homologous neurotoxins all proton signals in the aromatic and methyl regions as well as epsilon-ch2 proton signals of some lysine residues have been assigned to individual amino acid residues and their spatial microenvironment has been determined. the results deduced on ... | 1981 | 7297555 |
| naja naja oxiana venom fraction selectively induces ros-mediated apoptosis in human colorectal tumor cells by directly targeting mitochondria | objective: to investigate the selective effect of naja naja oxiana crude venom and its fractions on human colorectal cancer mitochondria to activate apoptosis signaling. methods: cells and mitochondria isolated from human cancerous and normal colorectal tissues exposed to n. oxiana crude venom and its fractions obtained from size-exclusion chromatography and then mitochondrial parameters related to up-stream cell death signalling such as reactive oxygen species formation, mmp, mitochondrial swel ... | 2017 | 28843256 |
| anticancer activity a of caspian cobra (naja naja oxiana) snake venom in human cancer cell lines via induction of apoptosis. | cancer is the leading cause of death worldwide. current anticancer drugs involve various toxic side effects; efforts are ongoing to develop new anticancer agents especially from the screening of natural compounds. present study investigated cytotoxic effects and mode of cell death induced by the caspian cobra venom in some human cancer cell lines. cytotoxic effects of snake venom toxins (svt) were investigated via monitoring of morphological changes, mtt, trypan blue exclusion and ldh release as ... | 2016 | 28228809 |
| naja naja oxiana cobra venom cytotoxins cti and ctii disrupt mitochondrial membrane integrity: implications for basic three-fingered cytotoxins. | cobra venom cytotoxins are basic three-fingered, amphipathic, non-enzymatic proteins that constitute a major fraction of cobra venom. while cytotoxins cause mitochondrial dysfunction in different cell types, the mechanisms by which cytotoxins bind to mitochondria remain unknown. we analyzed the abilities of cti and ctii, s-type and p-type cytotoxins from naja naja oxiana respectively, to associate with isolated mitochondrial fractions or with model membranes that simulate the mitochondrial lipid ... | 2015 | 26091109 |
| study on camel igg purification: a new approach to prepare naja naja oxiana antivenom as passive immunization for therapy. | a combined process of ammonium sulfate precipitation (salting out) and ion-exchange chromatography on deae-sepharose cl-6b was used to prepare camel antivenom (igg) against naja naja oxiana for therapy. in the ammonium sulfate precipitation, the best condition for fractionation of igg from the other proteins in camel serum was 55% precipitate. the camel igg presented as 2 bands with molecular masses of 250 and 100 kda, the latter corresponding to heavy chain igg, on 10% gel electrophoresis. a tr ... | 2014 | 24642472 |
| protective effects of hypothalamic proline-rich peptide and cobra venom naja naja oxiana on dynamics of vestibular compensation following unilateral labyrinthectomy. | we tested the action of proline-rich peptide (prp-1) and cobra venom naja naja oxiana (nox) on deiters' nucleus neurons at 3rd, 15th and 35th days after unilateral labyrinthectomy (ul). early and late tetanic, post-tetanic potentiation and depression of deiters'neurons to bilateral high frequency stimulation of hypothalamic supraoptic and paraventricualar nuclei was studied. the analysis of spike activity was carried out by mean of on-line selection and special program. the complex averaged peri ... | 2010 | 20703940 |
| preparation of chitosan nanoparticles containing naja naja oxiana snake venom. | hydrophilic nanoparticles have received much attention for delivery of therapeutic peptides, proteins, and antigens. chitosan (cs) is a biodegradable and nontoxic polysaccharide, as a carrier for drug delivery. the study purpose was to evaluate the influence of a number of factors on the encapsulation of naja naja oxiana (indian or speckled cobra) venom and loading capacity, as well as to investigate the physicochemical structure of nanoparticles. cs nanoparticles were produced based on the ioni ... | 2010 | 19616121 |
| loop 3 of short neurotoxin ii is an additional interaction site with membrane-bound nicotinic acetylcholine receptor as detected by solid-state nmr spectroscopy. | the contact area of neurotoxin ii from naja naja oxiana when interacting with the membrane-bound nicotinic acetylcholine receptor from torpedo californica was determined by solid-state, magic-angle spinning nmr spectroscopy. for this purpose, the carbon signals for more than 90% of the residues of the bound neurotoxin were assigned. differences between the solution and solid-state chemical shifts of the free and bound form of the toxin are confined to distinct surface regions. loop ii of the sho ... | 2009 | 19447114 |
| solution structure of long neurotoxin ntx-1 from the venom of naja naja oxiana by 2d-nmr spectroscopy. | the nmr solution structures of ntx-1 (pdb code 1w6b and bmrb 6288), a long neurotoxin isolated from the venom of naja naja oxiana, and the molecular dynamics simulation of these structures are reported. calculations are based on 1114 noes, 19 hydrogen bonds, 19 dihedral angle restraints and secondary chemical shifts derived from 1h to 13c hsqc spectrum. similar to other long neurotoxins, the three-finger like structure shows a double and a triple stranded beta-sheet as well as some flexible regi ... | 2004 | 15606783 |
| two forms of cytotoxin ii (cardiotoxin) from naja naja oxiana in aqueous solution: spatial structures with tightly bound water molecules. | 1h-nmr spectroscopy data, such as noe intraprotein and (bound water)/protein contacts, 3j coupling constants and deuterium exchange rates were used to determine the in-solution spatial structure of cytotoxin ii from naja naja oxiana snake venom (ctii). exploiting information from two 1h-nmr spectral components, shown to be due to cis/trans isomerization of the val7-pro8 peptide bond, spatial structures of ctii minor and major forms (1 : 6) were calculated using the torsion angle dynamics algorit ... | 1999 | 10429199 |
| benzophenone-type photoactivatable derivatives of alpha-neurotoxins and alpha-conotoxins in studies on torpedo nicotinic acetylcholine receptor. | by chemical modification of different lysine residues, benzoylbenzoyl (bzbz) groups were introduced into neurotoxin ii naja naja oxiana (nt-ii), a short-chain snake venom alpha-neurotoxin, while p-benzoylphenylalanyl (bpa) residue was incorporated in the course of peptide synthesis at position 11 of alpha-conotoxin g1, a neurotoxic peptide from marine snails. although the crosslinking yields for iodinated bzbz derivatives of nt-ii and for bpa analogue of g1 to the membrane-bound torpedo californ ... | 2014 | 10071785 |
| [secondary structure and conformational heterogeneity of naja naja oxiana cytotoxin ii]. | the proton resonances of cytotoxin ii from naja naja oxiana were sequentially assigned in 2d 1h nmr spectra for all of its 60 amino acid residues of both major and minor components of the spectra. the presence of the minor component was shown to be due to a conformational heterogeneity of the cytotoxin. the proton-deuterium exchange rates of amide groups were measured in 2h2o at a ph of 5.0 and at 10 degrees c. experimental data obtained (d-connectivities, h-nc alpha-h coupling constants and lon ... | 1996 | 8929219 |
| [refinement of the spatial structure of neurotoxin ii from naja naja oxiana venom]. | a set of 19 conformations of the neurotoxin ii from naja naja oxiana was determined by conformational energy minimization using constraints derived from experimental 1h nmr data. the pairwise average root-mean-square deviations were 0.86 a for the backbone heavy atoms and 1.48 a for all heavy atoms of these conformations. a model of the neurotoxin ii dimer is proposed to account for the relatively slow deuterium exchange rates of the val45 and leu51 amide protons, which are exposed to the solven ... | 1995 | 8540898 |
| photolabeling reveals the proximity of the alpha-neurotoxin binding site to the m2 helix of the ion channel in the nicotinic acetylcholine receptor. | a photoactivatable derivative of neurotoxin ii from naja naja oxiana containing a 125i-labeled p-azidosalicylamidoethyl-1,3'-dithiopropyl label at lys-25 forms a photo-induced cross-link with the delta subunit of the membrane-bound torpedo californica nicotinic acetylcholine receptor (achr). the cross-linked radioactive receptor peptide was isolated by reverse-phase hplc after tryptic digestion of the labeled delta subunit. the sequence of this peptide, delta-(260-277), and the position of the l ... | 1995 | 7543679 |
| synthesis of nitrodiazirinyl derivatives of neurotoxin ii from naja naja oxiana and their interaction with the torpedo californica nicotinic acetylcholine receptor. | five singly modified nitrodiazirine derivatives of neurotoxin ii (nt-ii) from naja naja oxiana were obtained after nt-ii reaction with n-hydroxysuccinimide ester of (2-nitro-4-[3-(trifluoromethyl)-3h-diazirin-3yl]phenoxy)acet ic acid followed by chromatographic separation of the products. to localize the label positions, each derivative was first uv-irradiated and then subjected to reduction, carboxymethylation, and trypsinolysis. tryptic digests were separated by reversed phase-hplc, the labele ... | 1995 | 7662107 |
| a new class of photoactivatable and cleavable derivatives of neurotoxin ii from naja naja oxiana. synthesis, characterisation, and application for affinity labelling of the nicotinic acetylcholine receptor from torpedo californica. | a new series of photoactivatable and cleavable derivatives of neurotoxin ii from the cobra naja naja oxiana is investigated which can be used for mapping the surface topology of the nicotinic acetylcholine receptor from torpedo electric tissue. the preparation and characterisation of five toxin derivatives, each with a radioactive 125i-azidosalicylamidoethyl-1,3'-dithiopropyl group in a defined position within the primary structure, are described. the photoinduced cross-linking reaction of the t ... | 1995 | 7737199 |
| [fragments 183-198 and 125-145 of the alpha-subunits of the torpedo californica nicotinic acetylcholinergic receptor binds alpha-bungarotoxin and neurotoxin ii from naja naja oxiana]. | interaction of the mono[125i]iodinated alpha-bungarotoxin and neurotoxin ii naja naja oxiana with the synthetic peptides corresponding to the fragments of the alpha-subunit of nicotinic acetylcholine receptor from torpedo californica was studied. it was found that both toxins bind to the fragments alpha 186-198, alpha 183-198 and alpha 125-145 adsorbed to the 96-well p.e.t.g. assay plates (costar). acm-groups on cys residues did not prevent toxin binding by the peptides studied. determination of ... | 1995 | 7748208 |
| [structure of peptide fragments of the complex (lys(abz)26) neurotoxin ii from naja naja oxiana cross-linked with the nicotinic acetylcholine receptor from torpedo californica]. | after irradiating the acetylcholine receptor complex with the title neurotoxin derivative, the labeled delta-subunit was separated by preparative sds-page, reduced-carboxymethylated and cleaved with lysc endoproteinase. one of the radioactive peptides isolated by hplc was further purified by electrophoresis in a tricin gel. edman degradation of the radioactive fractions yielded the sequence of the delta-subunit fragment starting from phe148. the aspn-cleavage of the radioactive peptide from the ... | 1994 | 7826405 |
| relationship between the binding sites for an alpha-conotoxin and snake venom neurotoxins in the nicotinic acetylcholine receptor from torpedo californica. | photoinduced cross-links between the iodinated lys26-p-azidobenzoyl derivative of neurotoxin ii from naja naja oxiana cobra venom and nicotinic acetylcholine receptor from torpedo californica (achr) have been studied in the presence of alpha-conotoxin gi from the marine snail c. geographus. preincubation of the achr-enriched membranes with increasing concentrations of alpha-conotoxin gi protects first the gamma subunit from photolabelling and then the delta subunit, the ic50 values being 0.76 an ... | 1994 | 7801351 |
| two-dimensional 1h-nmr study of the spatial structure of neurotoxin ii from naja naja oxiana. | the spatial structure of neurotoxin ii from the venom of the central asian cobra naja naja oxiana was determined by two-dimensional 1h-nmr techniques and computational analysis. nearly complete proton resonance assignments for 61 amino acid residues have been made using two-dimensional (2d) homonuclear total correlated spectroscopy, 2d homonuclear double-quantum-filtered correlated spectroscopy and 2d homonuclear noe spectroscopy (noesy) experiments. the cross-peak volumes in noesy spectra spin- ... | 1993 | 8504813 |
| three-dimensional structure of neurotoxin-1 from naja naja oxiana venom at 1.9 a resolution. | neurotoxin-1 from naja naja oxiana venom (ntx-1) has been crystallized by vapor diffusion in sitting drops. the crystals have cell dimensions of a = 25.2 a, b = 75.6 a, c = 35.9 a, and are in space group p2(1)2(1)2(1). three-dimensional data to 1.9 a have been recorded by a syntex p2(1) automatic diffractometer. the atomic structure of the toxin has been determined by molecular replacement using the alpha-cobratoxin (alpha-ctx) as the search model. the position of 534 non-hydrogen protein atoms ... | 1993 | 8458425 |
| mapping the functional topography of a receptor. | photoactivatable derivatives of the alpha-neurotoxin ii from naja naja oxiana are useful tools for investigating the three dimensional architecture of the extra-membrane part of the nicotinic acetylcholine receptor from the electric tissue of torpedo californica. three derivatives, carrying an azidobenzoyl group in position lys-15, lys-26, and lys-46, respectively, are shown to react differently within the receptor's quaternary structure. especially the lys-26 and lys-46 derivatives can be used ... | 2007 | 1299215 |
| anionic subsites of the catalytic center of acetylcholinesterase from torpedo and from cobra venom. | a peptide of acetylcholinesterase (acchoease; acetylcholine acetylhydrolase, ec 3.1.1.7) from the venom of the cobra naja naja oxiana labeled by the affinity reagent n,n-dimethyl-2-phenylaziridinium (dpa) has been identified. the sequence is gly-ala-glu-met-trp-asn-pro-asn. in acchoease from torpedo californica, a homologous peptide was labeled and isolated. its sequence is ser-gly-ser-glu-met-trp-asn-pro-asn, representing positions 79 through 87. in both cases labeling can be prevented by 0.1 m ... | 1991 | 2068091 |