| purification and characterization of a mutant human platelet phospholipase a2 expressed in escherichia coli. cleavage of a fusion protein with cyanogen bromide. | both methionine residues in phospholipase a2 (pla2) from porcine pancreas have been replaced by leucines with retention of full enzymatic activity. the methionine-less mutant has been expressed as a cro-lacz fusion protein in escherichia coli, from which a pro-pla2 was liberated by chemical cleavage with cnbr. the general applicability of cnbr cleavage of proteins lacking methionine residue(s) was demonstrated by replacing the single met8 in human platelet phospholipase a2 (hp-pla2) by a leucine ... | 1992 | 1730245 |
| hemolytic activity of thionin from pyrularia pubera nuts and snake venom toxins of naja naja species: pyrularia thionin and snake venom cardiotoxin compete for the same membrane site. | pyrularia thionin (p. thionin) is a strongly basic peptide of 47 amino acids which is hemolytic, cytotoxic and neurotoxic. it shows the greatest hemolytic activity toward human erythrocytes. rabbit, guinea pig and pig erythrocytes show decreasing activity in that order, and little or no activity is shown with sheep, horse, cow or mouse erythrocytes. crotalus venoms are inactive, but the venoms from naja naja atra, naja naja ceylonicus and naja naja melanoleuca and, more specifically, cardiotoxin ... | 1989 | 2749751 |
| properties of some 3-nitrotyrosyl elapid venom cardiotoxins. | nitration of the invariant tyr-22 in hemachatus haemachates cardiotoxin 12b did not greatly decrease lethality, and the haemolytic potency towards guinea-pig erythrocytes remained unchanged. this residue is thus non-essential for cardiotoxin to exert its biological action. nitration of naja haje annulifera and naja melanoleuca cardiotoxins vii1 decreased but did not abolish the lethalities and haemolytic potencies. thus tyr-25 and tyr-51 were concluded to have no direct functional role in cardio ... | 1987 | 3569641 |
| interaction of human plasma lecithin:cholesterol acyltransferase and venom phospholipase a2 with apolipoprotein a-i recombinants containing nonhydrolyzable diether phosphatidylcholines. | partially reassembled high density lipoproteins (r-hdl) composed of apolipoprotein a-i and nonhydrolyzable analogues of phosphatidylcholine have been prepared, and their physical properties and reactivities as substrates for lecithin: cholesterol acyltransferase and three phospholipases were tested. the stereo-chemical pairs l-dmpc-ether (1,2-o-ditetradecyl-sn-glycero-3-phosphorylcholine) and d-dmpc-ether (2,3-o-ditetradecyl-sn-glycero-1-phosphoryline) or l-dmpc (1,2-dimyristoyl-sn-glycero-3-pho ... | 1985 | 3930483 |
| neuromuscular blocking activity of snake (naja melanoleuca, hallowel) venom. | | 1974 | 4460285 |
| electrophysiological analysis of the presynaptic action of beta-bungarotoxin in the central nervous system. | in view of previously reported actions of beta-bungarotoxin (beta-butx) on central brain synaptosomes, the effects on this toxin on the electrical activity of two brain slice preparations have been examined in vitro. beta-butx initially suppresses the synaptic component of the field responses to electrical stimulation in olfactory cortex and hippocampal slices. intracellular recordings demonstrate that this synaptic depression occurs without detectable reduction in the sensitivity of the postsyn ... | 1982 | 6281937 |
| biochemical and pharmacological properties of cardiotoxins isolated from cobra venom. | it has been established that cardiotoxins isolated from elapidae snakes tend to be contaminated with phospholipase. after a thorough comparison of the methods available for the separation of these two components, both hydrophobic and immunoaffinity chromatography have been found to be convenient and effective methods. with cardiotoxins isolated from naja naja siamensis we observed that as the contaminating phospholipase was removed, the cardiotoxins were converted from relatively powerful haemol ... | 1982 | 7080031 |
| interaction of phospholipase a2 and phospholipid bilayers. | binding of phospholipase a2 from porcine pancreas and from naja melanoleuca venom to vesicles of 1,2-di(tetradecyl)-rac-glycero-3-phosphocholine (diether-pc14) is studied in the presence and absence of 1-tetradecanoyl-sn-glycero-3-phosphocholine and myristic acid. the bound enzyme coelutes with the vesicles during gel filtration through a nonequilibrated sephadex g-100 column, modifies the phase transition behavior of bilayers, and exhibits an increase in fluorescence intensity accompanied by a ... | 1982 | 7104328 |
| preparation of neurotoxic 3h-beta-bungarotoxin: demonstration of saturable binding to brain synapses and its inhibition by toxin i. | 1. homogeneous beta-bungarotoxin, isolated from the venom of bungarus multicinctus was radiolabelled with n-succinimidyl-[2.3-(3) h]propionate. stable, di-propionylated material was obtained which was tritiated on both subunits and had a specific radioactivity of 102 ci/mmol. 2. after separation from unlabelled toxin by isoelectric focussing, it was shown to exhibit significant biological activity in both the peripheral and central nervous systems but had negligible phospholipase a2 activity tow ... | 1982 | 7173209 |
| a three-compartment open pharmacokinetic model can explain variable toxicities of cobra venoms and their alpha toxins. | the pharmacokinetic profiles of labelled naja melanoleuca, naja nivea, naja nigricollis and naja haje venoms and their alpha neurotoxins were determined following rapid i.v. injection into rabbits. the data obtained fitted a triexponential equation characteristic of a three-compartment open pharmacokinetic model comprising a central compartment 'blood', a rapidly equilibrating 'shallow' tissue compartment and a slowly equilibrating 'deep' tissue compartment. the distribution half-lives for the s ... | 1996 | 8896193 |
| surface properties of native human plasma lipoproteins and lipoprotein models. | plasma lipoprotein surface properties are important but poorly understood determinants of lipoprotein catabolism. to elucidate the relation between surface properties and surface reactivity, the physical properties of surface monolayers of native lipoproteins and lipoprotein models were investigated by fluorescent probes of surface lipid fluidity, surface lateral diffusion, and interfacial polarity, and by their reactivity to naja melanoleuca phospholipase a2 (pla2). native lipoproteins were hum ... | 1998 | 9533698 |
| enzymatic properties of rat group iia and v phospholipases a(2) compared. | group iia and v phospholipases a(2) (pla(2)s) are known to play a role in inflammatory responses. we have constructed a bacterial expression vector for rat group iia and v pla(2)s, over-expressed, folded and purified the proteins with the aim to study and compare the properties of the enzymes in detail. for zwitterionic phospholipid micelles, both enzymes display optimum activity at ph 8. 0 and absolutely require ca(2+) for enzymatic activity. in the presence of substrate, group v pla(2) has a h ... | 1999 | 10477825 |
| antibacterial properties of kwazulu natal snake venoms. | the objective was to ascertain whether local snake venoms have antibacterial properties. the venoms of the common night adder (causus rhombeatus), gaboon adder (bitis gabonica), puff adder (bitis arietans), black mamba (dendroaspis polylepis), eastern green mamba (dendroaspis augusticeps), forest cobra (naja melanoleuca), snouted cobra (naja annulifera) and mozambique spitting cobra (naja mossambica) were collected and, by gel diffusion, tested against the bacteria staphylococcus aureus, escheri ... | 2000 | 10775753 |
| [comparative titration of three antivenin serums used against sub-saharan african snakes]. | the standardisation of serotherapy is necessary in africa mainly because of the frequency of envenomations and the lack of alternative treatments. comparative titrations of fav-afrique (aventis pasteur), polyvalent serum (serum institute of india = sii) and polyvalent antivenin (south african vaccine fabricants ltd = saimr) were carried out on venoms of echis ocellatus from cameroun, e. ocellatus from mali, e. leucogaster and naja melanoleuca. the 50% protective doses (ed50) of the antivenoms we ... | 2002 | 12404855 |
| naja melanoleuca cobra venom contains two forms of complement-depleting factor (cvf). | two forms of complement-depleting cobra venom factor (cvfm1 and cvfm2), possessing molecular masses of 142.6 kda (cvfm1) and 143.1 kda (cvfm2), according to maldi mass-spectrometry, were isolated from the naja melanoleuca cobra venom. as shown by polyacrylamide gel electrophoresis in the presence of sds, both forms similarly to factor from the naja kaouthia cobra venom (cvfk) consist of three polypeptide chains with molecular masses of about 70, 50, and 30 kda, the two large subunits being glyco ... | 2005 | 16054663 |
| [biogeographical distribution of snakes in cameroon: the case of venomous snakes]. | a preliminary analysis of the distribution of snakes captured in cameroon between 1999 and 2004 is presented in this study. this work helps to provide a better understanding of the distribution of the venomous snakes. the main focus of this study was to identify regions of high diversity of venomous species, a useful step towards developing a national strategy of snakebite care and antivenom distribution. we recorded 4,910 specimens of 150 species from 361 localities throughout cameroon. among t ... | 2005 | 16402580 |
| paraspecific neutralization of the venom of african species of cobra by an equine antiserum against naja melanoleuca: a comparative study. | venoms of snakes belonging to the same genera tend to share biochemical, toxinological and antigenic characteristics. accordingly, paraspecific neutralization of venom lethality by experimental antisera and commercial antivenoms has been reported. we studied the spectrum of neutralization of lethality of an experimental monovalent equine antiserum against the strongly neurotoxic african forest cobra (naja melanoleuca) when tested against venoms of most species of african naja, both neuro and cyt ... | 2009 | 19673073 |
| amino acid sequence of a presynaptic neurotoxin from the venom of notechis scutatus scutatus (australian tiger snake). | the complete amino acid sequence of notexin, a presynaptic neurotoxin from the venom of notechis scutatus scutatus (australian tiger snake), has been elucidated. the protein consists of a single chain of 119 amino acids cross-linked by seven disulfide bridges and has a formula weight of 13,578. the main fragmentation of the peptide chain was accomplished with a staphylococcal protease specific for glutamoyl bonds. a cyanogen bromide fragment and tryptic peptides were used to align the five major ... | 1996 | 1158892 |
| the oxidation of methionine and its effect of the properties of cardiotoxin vii1 from naja melanoleuca venom. | methionine residues 24 and 26 of cardiotoxin vii1 from naja melanoleuca were oxidised to sulphoxides using n-chlorosuccinimide at ph 8.5. the number of equivalents of oxidant required for complete oxidation suggested that the methionine side-chains existed in a relatively "exposed" conformational state in cardiotoxin. the oxidised cardiotoxin was devoid of lethality. it was also non-haemolytic, both on its own and in the presence of phospholipase a2. however, it was still able to precipitate wit ... | 1999 | 96866 |
| evaluation of antimicrobial and antiviral activities of different venoms. | animals' venomous secretions or peptides obtained from those secretions are used in the development of new therapeutic agents. the aims of this study were to investigate antimicrobial and antiviral activity of four different venoms obtained from the frog named bufo arenarum and the snakes crotalus atrox, causus rhombeatus and naja melanoleuca. | 2016 | 26743517 |
| molecular cloning and characterization of a complement-depleting factor from king cobra, ophiophagus hannah. | cobra venom factor (cvf) is an anti-complement factor existing in cobra venom. cvf proteins have been purified from the venoms of naja haje, naja siamensis, naja atra, naja kaouthia, naja naja, naja melanoleuca and austrelaps superbus, but only three full-length cdna sequences of cvf are available. in the present work, a cobra venom factor termed ovf was purified from the crude venom of ophiophagus hannah by successive gel filtration, ion-exchange and heparin affinity chromatography steps. the p ... | 2012 | 22561424 |
| [mortality from snake bites, wild and domestic animal bites and arthropod stings in the savannah zone of eastern senegal]. | from 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern senegal. of 4,228 deaths registered during this period, 26 were brought on by snakebites, 4 by invertebrate stings and 8 by other wild or domestic animals. the average annual mortality rate from snakebite was 14 deaths per 100,000 population. among persons aged 1 year or more, 0.9% (26/2,880) of deaths were caused by snakebite and this cause represented ... | 2002 | 12404858 |
| high mortality from snakebite in south-eastern senegal. | over 24 years, from 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern senegal. of 4228 deaths registered during this period, 26 were caused by snakebite, 4 by invertebrate stings and 8 by other wild or domestic animals. the average annual mortality rate from snakebite was 14 deaths per 100,000 population. among persons aged > or = 1 year, 0.9% (26/2880) of deaths were caused by snakebite and this cause repr ... | 2004 | 11579888 |
| [biochemical variations of west african snake venoms]. | electrophoretic patterns of bitis gabonica, bitis nasicornis, bitis arietans venoms have shown specific and individual variations; neither physiological nor seasonal differences were noticed. immunoelectrophoretic study of naja melanoleuca and naja nigricollis individual venoms revealed a variation in neurotoxin concentration from one venom to another. deletion of some minor fractions is noticed in few venoms. the authors think it of major interest to work on individual venoms. | 2013 | 7285271 |
| naja melanoleuca (forest cobra) venom. the amino acid sequence of phospholipase a, fraction de-iii. | reduced and s-carboxymethylated phospholipase a (fraction de-iii) from naja melanoleuca venom was digested with trypsin, chymotrypsin and thermolysin. the resulting peptides were purified by ion-exchange chromatography on deae-cellulose, gel filtration on sephadex g-25 or g-50 and chromatography and electrophoresis on paper. the amino acid sequences of the intact enzyme and the pur peptides were determined by the edman procedure, either through the use of the automatic sequencer or by manual man ... | 1975 | 1122291 |
| the complete amino-acid sequence of a basic phospholipase a2 in the venom of bungarus fasciatus. | a basic phospholipase a2 (pla2) was isolated and purified from the venom of bungarus fasciatus. four kinds of enzymes, lysyl endopeptidase, endoproteinase asp-n, endoproteinase glu-c and trypsin, were employed to elucidate the complete primary structure by means of gas-phase sequencing. the amino-acid sequence reveals 118 amino-acid residues containing seven pairs of half-cystine. it has 78% and 61% structural identities with pla2 from bungarus multicinctus and naja melanoleuca de-ii, respective ... | 1988 | 3072971 |
| evidence for existence of venom 5' nucleotidase in multiple forms through inhibition of concanavalin a. | pharmacologically active 5' nucleotidase is a ubiquitously distributed enzyme in snake venoms. in this study the effect of concanavalin a (con-a) on different snake venoms 5' nucleotidase activity is tested in order to know the protein nature which will ultimately help in purification of the enzyme with high yield. con-a inhibited naja naja, naja kauthia, naja melanoleuca, naja naja sputatrix, agistrodon halys blomhoffii, bothrops asper and oxyranus scutellas venom 5' nucleotidase activity at di ... | 2010 | 20941753 |
| ophidian l-amino acid oxidase. the nature of the enzyme-substrate complexes. | 1. to investigate the kinetics of ophidian l-amino acid oxidase, v and k(m) were determined for phenylalanines that were substituted in every ring position with groups of various size and reactivity, and for a few ring-substituted tryptophans and histidines. the venom of one representative from each of three major classes of poisonous snakes, naja melanoleuca, vipera russelli and crotalus adamanteus, served as a source of the ophidian l-amino acid oxidase. both crude and crystalline enzyme from ... | 1965 | 14335813 |
| [preliminary results of an herpetology investigation in sugar cane plantation in democratic republic of congo]. | out of the 3,000 species of snakes described in the world, 163 are currently known from d.r. of congo. we performed a systematic survey in sugar-cane plantations of the sugar company of kwilu-ngongo (bas-congo), located at 160 km south-west from kinshasa and exploiting nearly 10,000 ha. the plantation is divided into 3 sectors in the middle of which we deposited barrels filled of formaldehyde. all the employees of the sugar company of kwilu-ngongo were requested to collect encountered snakes and ... | 2005 | 16402584 |
| 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 |
| the preparation of 3-nitrotyrosyl derivatives of three elapid venom cardiotoxins. | nitration studies using tetranitromethane were conducted on the tyrosine residues of cardiotoxins, naja melanoleuca vii1, naja haje annulifera vii1 and hemachatus haemachates toxin 12b. various partially and fully nitrated derivatives were formed. analysis of the products of nitrating naja melanoleuca vii1 showed that the average relative reactivities of the three tyrosine residues were tyr-25 greater than tyr-22 greater than tyr-51. it was significant that tyr-51 could be easily modified in bot ... | 1980 | 7417487 |
| naja haje haje (egyptian cobra) venom. some properties and the complete primary structure of three toxins (cm-2, cm-11 and cm-12). | three toxins (cm-2, cm-11 and cm-12) were purified from naja haje haje (egyptian cobra) venom. whereas toxin cm-11 contains 65 amino acid residues and five intrachain disulphide bridges, toxin cm-2 and cm-12 comprise, respectively, 61 and 62 residues but both contain four disulphide bridges. the complete primary structures of the three toxins have been established. the sequence and the invarient amino acid residues of cm-2 resemble those of part of a long neurotoxin, a short neurotoxin and a cyt ... | 1978 | 710433 |
| the purification and amino acid sequence of toxin cm-13b from naja haje annulifera (egyptian cobra) venom. | toxin cm-13b was purified from the venom of naja haje annulifera by gel filtration on sephadex g-50 and by ion-exchange chromatography on cm-cellulose. the toxin comprises 65 amino acid residues and is cross-linked by five disulphide bridges. the complete amino acid sequence of toxin cm-13b was elucidated. the reduced and s-carboxymethylated toxin was digested with trypsin and chymotrypsin and the peptides purified by deae-cellulose chromatography and chromatography or electrophoresis on paper. ... | 1975 | 1213685 |
| amino-acid sequence of toxin iii of naja haje. | the complete amino acid sequence of toxin iii of naja haje (72 residues) has been established mainly by use of a protein sequenator (identification of 70 residues). the two c-terminal residues have been determined by digestion with carboxypeptidases a and b. addition of succinylated protein or peptide greatly improved the performance of the sequenator for the edman degradation of peptides: on one peptide (39 residues) degradation went to step 34 with a protein program and on two peptides (10 and ... | 1975 | 1183429 |
| exploring the venom of the forest cobra snake: toxicovenomics and antivenom profiling of naja melanoleuca. | a toxicovenomic analysis of the venom of the forest cobra, n. melanoleuca, was performed, revealing the presence of a total of 52 proteins by proteomics analysis. the most abundant proteins belong to the three-finger toxins (3ftx) (57.1wt%), which includes post-synaptically acting α-neurotoxins. phospholipases a2(pla2) were the second most abundant group of proteins (12.9wt%), followed by metalloproteinases (svmps) (9.7wt%), cysteine-rich secretory proteins (crisps) (7.6wt%), and kunitz-type ser ... | 2017 | 27593527 |
| [the severity of a snake bite. apropos of 3 case reports in the congo]. | three observations of sanke-bite that occurred in the congo are reported: the bite of an aglyph colubridae (philothamnus nitidus loveridgee) that was severe; the bite of an atheris s.p. with moderate symptoms; the bite of a naja melanoleuca remained totally asymptomatic. | 1992 | 1417162 |
| schumanniofoside, the antisnake venom principle from the stem bark of schumanniophyton magnificum harms. | the methanol extract of the stem bark of schumanniophyton magnificum and schumanniofoside, a chromone alkaloidal glycoside isolated from it, reduced the lethal effect of black cobra (naja melanoleuca) venom in mice. this effect is greatest when the venom is mixed and incubated with the extract or schumanniofoside. it is thought that the mode of action is by oxidative inactivation of the venom. | 1986 | 3560994 |
| interaction of native and modified naja melanoleuca phospholipases a2 with the fluorescent probe 8-anilinonaphtalene-1-sulfonate. | the fluorescent probe 8-anilinonaphtalene-1-sulfonate (ans) binds at the active site of the naja melanoleuca snake venom phospholipase a2, thus protecting the enzyme against active-site-directed chemical modification. both hydrophobic and electrostatic interactions are involved in the binding. at ph 7.5, a binding constant of 100 microm was determined, which improved twofold upon addition of the enzymatic cofactor ca2+. the ph dependence of the ans binding in the absence and presence of ca2+ ion ... | 1984 | 6714237 |
| characterization of phospholipases a2 of naja melanoleuca snake venom modified at the n-terminal region. | in phospholipase a2 from naja melanoleuca snake venom all four lysines were converted into the epsilon-amidinated derivatives without reaction of the alpha-amino group. the amidinated phospholipase (ampa) showed high enzymatic activity. starting from ampa, chemical modification reactions were carried out at the alpha-amino function. this group was blocked with a tert-butyloxycarbonyl or a phenylthiocarbamyl group. furthermore the polypeptide chain was shortened by one residue by removing the n-t ... | 1984 | 6421576 |
| interaction of phospholipase a2 from naja melanoleuca snake venom with monomeric substrate analogs. activation of the enzyme by protein-protein or lipid-protein interactions? | unlike porcine pancreatic phospholipase a2, the enzyme from naja melanoleuca does not display biphasic kinetic behaviour at substrate concentrations around the critical micelle concentration. this snake venom enzyme was further investigated by direct binding studies using n-tridecylphosphocholine. binding of this substrate analog to the enzyme was monitored by using equilibrium gel filtration, equilibrium dialysis and ultraviolet difference spectroscopy. it is concluded that, in the presence of ... | 1983 | 6840082 |
| chemical modification of lys-6 in phospholipase a2 from naja melanoleuca snake venom. | phospholipase a2 isolated from naja melanoleuca snake venom was modified with 4-chloro-3,5-dinitrobenzoate. the modification reaction was accelerated by the cofactor ca2+. micellar concentrations of the substrate analog n-tetradecylphosphocholine retarded the inactivation of the enzyme. modification resulted in the incorporation of one mole dinitrobenzoate/mole of protein. the modified residue could be identified as lys-6 in the amino acid sequence of the enzyme. although the modified enzyme sti ... | 1983 | 6404627 |
| snake venom toxins. the primary structure of protein s4c11. a neurotoxin homologue from the venom of forest cobra (naja melanoleuca). | six minor protein constituents (s4c10-s4c15) have been isolated from the venom of naja melanoleuca. the complete amino acid sequence of s4c11 has been established and indicates that it is a homologue of the neurotoxins which are found in elapid venoms. the other proteins appear from the amino acid compositions to be homologues of the cyto- or cardiotoxins found in cobra venoms. protein s4c11 has a low toxicity, failing to kill mice at an intravenous dose of 20 mug/g body weight. the sequence of ... | 1975 | 1164509 |
| the primary structure of a major polypeptide component from the venom of naja melanoleuca. | the venom of the forest cobra, naja melanoleuca, contains a number of homologous polypeptides containing between 60 and 71 amino acid resides. the primary structure of a major component (approx. 10% by weight of the crude venom) has been determined unambiguously. the molecule contians 61 amino acid residues and four disulphide bridges. it has not effect on neuromuscular transmission or the excitatory or inhibitory responses to acetylcholine of molluscan neurons. the molecule is similar to, but n ... | 1975 | 1175634 |
| [three neurotoxins of naja melanoleuca venom]. | a serological study of three fractions extracted from naja melanoleuca venom has demonstrated that one of these fractions belongs to the serological group i according to the classification we have established. it is a curary-like "short" toxin (61 amino-acid residues, 8 half cystine). the second and the third fractions belong to the serological group iii, i.e., to the group of "long curary-like toxins" (71 amino-acids residues, 10 half cystines). | 1975 | 807371 |
| the amino acid sequence of phospholipase a, fractions de-i and de-ii. | the complete amino acid sequences of phospholipase a (fractions de-i and de-ii) from naja melanoleuca (forest cobra) have been elucidated. the reduced and s-carboxymethylated isoenzyme were digested with trypsin and thermolysin and the peptides were purified by ion-exchange chromatography, gel filtration and chromatography or electrophoresis on paper. the edman procedure, either through the use of the automatic sequencer or by manual manipulation, was employed to obtain the sequences of the inta ... | 1975 | 1122292 |
| naja melanoleuca (forest cobra) venom. purification and some properties of phospholipases a. | three phospholipases a (fractions de-i, de-ii and de-iii) were purified from naja melanoleuca (forest cobra) venom by a combination of gel filtration on sephadex g-50 and chromatography on deae-cellulosemthe purified phospholipases a were homogeneous by various physicochemical criteria. whereas fraction de-i contains 118 amino acid residues, fractions de-ii and de-iii comprise 119 residues. the three enzymes are cross-linked by seven disulphide bridges, have asparagine as n-terminal amino acid a ... | 1975 | 1122290 |
| snake venom toxins. the primary structures of two novel cytotoxin homologues from the venom of forest cobra (naja melanoleuca). | | 1974 | 4842298 |
| the separation of neurotoxin from the venom of naja melanoleuca and the primary sequence determination. | | 1974 | 4830190 |
| snake venom toxins. the amino acid sequences of toxins b and d from naja melanoleuca venom. | | 1972 | 4112538 |
| [properties of 3 toxins isolated from the venom of one of the elapidae: naja melanoleuca]. | | 1972 | 4625148 |
| effects of three cobra venoms on blood coagulation, platelet aggregation, and fibrinolysis. | the effects of the venoms of naja melanoleuca, naja nigricollis, and ophiophagus hannah on blood coagulation, platelet aggregation, and fibrinolysis were studied in vitro. all three venoms were shown to be anticoagulant. this action appeared to be due to an effect on both the extrinsic and blood thromboplastin mechanisms. platelet aggregation in chandler's tubes and adenosine diphosphate reactivity were inhibited by the three venoms, although in the case of ophiophagus hannah venom they were inh ... | 1969 | 5814735 |
| distinctive distribution of secretory phospholipases a₂ in the venoms of afro-asian cobras (subgenus: naja, afronaja, boulengerina and uraeus). | the protein abundances of phospholipases a₂ in cobra venom proteomes appear to vary among cobra species. to determine the unique distribution of snake venom phospholipases a₂ (svpla₂) in the cobras, the svpla₂ activities for 15 cobra species were examined with an acidimetric and a colorimetric assay, using egg yolk suspension and 4-nitro-3-octanoyloxy benzoic acid (noba) as the substrate. the colorimetric assay showed significant correlation between svpla₂ enzymatic activities with the svpla₂ pr ... | 2019 | 30769779 |
| snake venoms promote stress-induced senescence in human fibroblasts. | snake venoms are widely studied in terms of their systemic toxicity and proteolytic, hemotoxic, neurotoxic, and cytotoxic activities. however, little is known about snake-venom-mediated effects when used at low, noncytotoxic concentrations. in the current study, two human fibroblast cell lines of different origin, namely wi-38 fetal lung fibroblasts and bj foreskin fibroblasts were used to investigate snake-venom-induced adaptive response at a relatively noncytotoxic concentration (0.01 µg/ml). ... | 2019 | 30317566 |
| retraction note: severe viperidae envenomation complicated by a state of shock, acute kidney injury, and gangrene presenting late at the emergency department: a case report. | the authors have retracted this case report [1] because the head of the snake shown in figure 1 and described as being that of a viper (echis occellatus) is identical to the head of a snake shown in figure 1 of a different case report [2] where it was identified as being naja melanoleuca, a member of the elapidae family. | 2020 | 32228476 |
| integration of nuclear and mitochondrial gene sequences and morphology reveals unexpected diversity in the forest cobra (naja melanoleuca) species complex in central and west africa (serpentes: elapidae). | cobras are among the most widely known venomous snakes, and yet their taxonomy remains incompletely understood, particularly in africa. here, we use a combination of mitochondrial and nuclear gene sequences and morphological data to diagnose species limits within the african forest cobra, naja (boulengerina) melanoleuca. mitochondrial dna sequences reveal deep divergences within this taxon. congruent patterns of variation in mtdna, nuclear genes and morphology support the recognition of five sep ... | 2018 | 30314221 |