Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| note on crotalus adamanteus. | 1893 | 17729788 | |
| an experimental glomerular lesion caused by venom (crotalus adamanteus). | the venom of crotalus adamanteus when administered intravenously to rabbits in properly graded doses causes lesions of the glomerulus of tile kidney which may be either hemorrhagic or exudative in character. both types of lesion are usually associated but either one or the other may predominate. the hemorrhagic lesion, which may be confined to the glomerular tuft, or, by rupture of the latter, may involve the capsular space, is a peculiar localization of the hemorrhage so common in other parts o ... | 1909 | 19867264 |
| the coagulation of blood by snake venoms and its physiologic significance. | nine of the 17 venoms here tested were found capable of coagulating citrated blood or plasma. as has been believed by most workers in the field, 7 of these 9 coagulant venoms convert fibrinogen to an insoluble modification resembling fibrin (bothrops atrox, bothrops jararaca, bothrops nummifera, crotalus adamanteus, crotalus horridus, crotalus terrificus basiliscus, crotalus terrificus terrificus). the optimum ph for this coagulation was determined for 3 of these, and was found in each case to b ... | 1937 | 19870622 |
| case of serious florida diamondback rattlesnake (crotalus adamanteus) bite. | 1954 | 13211946 | |
| acute toxicity and treatment of intoxications due to crotalus adamanteus (rattlesnake venom). | 1958 | 13559236 | |
| hematologic effects of crotalus adamanteus (rattlesnake) venom. | 1959 | 14435756 | |
| the treatment of diamondback rattlesnake bite (crotalus adamanteus), vitamin k an adjunct. | 1960 | 13683476 | |
| crystalline l-amino acid oxidase of crotalus adamanteus. | 1960 | 13843884 | |
| studies on the biologic relationship of endotoxin and other toxic proteins. ii. enhancement of susceptibility to snake venom by endotoxin. | 1. injections of sublethal quantities of agkistrodon piscivorus venom into endotoxin-treated rabbits produces a consistent early death. 2. the endotoxin-induced hypersusceptibility state (eihs) to venom is produced by intravenous, intradermal, and intraperitoneal administration of endotoxin. the latency and duration of the eihs vary with the route of administration. 3. eihs is induced by as little as 1 gamma of endotoxin administered intravenously. although the degree of susceptibility was no gr ... | 1962 | 13916025 |
| a new acute phase protein elicited in mice by streptolysin o and other toxic or infectious agents. | a new acute phase plasma component has been found in mice exposed to certain toxic materials and pathogenic bacteria. the abnormal component, detected by immunodiffusion employing absorbed antiserum, was chiefly studied in plasma of streptolysin o-treated mice where it appears within 24 hours after intravenous administration of a sublethal dose of the toxin. the new factor is a protein having the electrophoretic mobility of a slow alpha2-globulin. it is devoid of lipid and separate from the stre ... | 1965 | 4158436 |
| 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 |
| phospholipase a properties of several snake venom preparations. | the hydrolytic properties of the venoms of seven species of snakes,crotalus adamanteus, ancistrodon contortrix, naja naja, bothrops atrox, ophiophagus hannah, crotalus atrox andvipera russeli, were studied with purified lecithins and mixtures of lecithins of known fatty acid and class composition as substrates.the relative rates of hydrolysis of the fatty acids by the above venoms were studied by analysis of the products of the reaction at intervals during the course of the reaction. of the seve ... | 1966 | 17805626 |
| the diagnosis, symptoms, treatment and sequella of envenomation by crotalus adamanteus and genus agkistrodon. | 1966 | 6004039 | |
| on the reaction mechanism of crotalus adamanteus l-amino acid oxidase. | 1967 | 6067195 | |
| the influence of the esterification of the 3'(2') hydroxyl group of trna on the hydrolysis by venom phosphodiesterase (crotalus adamanteus) was studied. it was shown that this esterification does not change the rate of hydrolysis. at ph 7-8, no significant differences were observed either when the alpha amino group of the attached amino acid was free or blocked, or when the aminoacid contained a free carboxyl group or a second amino group (glutamic acid or lysine). aminoacyl-amp or oligopeptidyl ... | 1968 | 11945280 | |
| diagnosis, symptoms, treatment and sequelae of envenomation by crotalus adamanteus and genus ancistrodon. | 1968 | 5646640 | |
| venom neutralization by rattlesnake serum albumin. | the blood serum of the eastern diamond back rattlesnake (crotalus adamanteus) neutralizes lethal doses of c. adamanteus venom in mice. the protective capacity of the serum is associated with the serum albumin, rather than the immunoglobulin fraction of the blood. neither the serum nor its albumin fraction form precipitin bands on immunophoresis against venom. | 1969 | 5783711 |
| studies on phospholipase a. i. isolation and characterization of two enzymes from crotalus adamanteus venom. | 1969 | 5777339 | |
| afibrinogenemia in man following the bite of a rattlesnake (crotalus adamanteus). | 1969 | 5822979 | |
| thrombic enzyme from crotalus adamanteus. | 1970 | 4194151 | |
| purification and properties of a thrombin-like enzyme from the venom of crotalus adamanteus (eastern diamondback rattlesnake). | 1971 | 5132665 | |
| spectral peculiarities of the monomer-dimer transition of the phospholipases a 2 of crotalus adamanteus venom. | 1971 | 5168612 | |
| evidence that the phospholipase a 2 of crotalus adamanteus venom are dimers. | 1971 | 5168611 | |
| evidence for o-acyl cleavage during hydrolysis of 1,2-diacyl-sn-glycero-3-phosphorylcholine by the phospholipase a 2 of crotalus adamanteus venom. | 1971 | 5168779 | |
| a kinetic study of the phospholipase a 2 (crotalus adamanteus) catalyzed hydrolysis of 1,2-dibutyryl-sn-glycero-3-phosphorylcholine. | 1972 | 5062536 | |
| a purified procoagulant enzyme from the venom of the eastern diamondback rattlesnake (crotalus adamanteus): in vivo and in vitro studies. | 1972 | 4623612 | |
| distribution and excretion of 3h-venoms of crotalus adamanteus, crotalusatrox, and agkistrodon piscivorus and 3h-serum of lampropeltis getulus in rats. | 1972 | 5058627 | |
| crotalus adamanteus basic protein toxin: electron microscopic evaluation of myocardial damage. | 1973 | 4125228 | |
| effects of chemical modification on the activity of crotalus adamanteus phospholipase a 2 . evidence for an essential amino group. | 1973 | 4734661 | |
| spectral perturbations of crotalus adamanteus phospholipase a 2 induced by divalent cation binding. | 1973 | 4734660 | |
| purification of exonuclease (phosphodiesterase) from the venom of crotalus adamanteus. | 1974 | 4374207 | |
| rapid purification of phospholipase a2 from crotalus adamanteus venom by affinity chromatography. | we have used alkyl ether analogs of ethanolamine and choline phospholipids as ligands to purify phospholipase a2 (ec 3.1.1.4) from crotalus adamanteus venom by affinity chromatography. one of the affinity columns was prepared with rac-1-(9-carboxy)nonyl-2-hexadecylglycero-3-phosphocholine linked to ah-sepharose 4b via the carboxyl group. specific adsorption of phospholipase a2 to this column was achieved in buffer containing ca2+, and the enzyme was eluted in buffer containing edta. the two enzy ... | 1975 | 1171865 |
| crotalus adamanteus phospholipase a2-alpha: subunit structure. nh2-terminal sequence, and homology with other phospholipases. | 1975 | 1124937 | |
| a simple method for preparation of snake venom phosphodiesterase almost free from 5'-nucleotidase. | a simple method, involving nad+-sepharose chromatography, was developed for the preparation of snake venom phosphodiesterase (ec 3.1.4.1) almost free from 5'-nucleotidase (ec 3.1.3.5). using an nad+-sepharose 4b column, phosphodiesterase was eluted in the unadsorbed fraction, whereas 5'nucleotidase was strongly adsorbed. the latter enzyme was desorbed when 0.2 m sodium bicarbonate buffer containing 1mm beta-nadh was used as a solvent. the affinity column could be used at least four times without ... | 1975 | 168189 |
| a simple and high yield purification of crotalus adamanteus phospholipases a2. | a new, high yield, procedure for the purification of the phospholipases a2 of crotalus adamanteus venom is described. the procedure involves precipitation of the bulk of venom proteins with 50% isopropanol, precipitation of the enzymes from the isopranol soluble material with neodynium chloride, and final purification on deae cellulose. an overall yield of approximately 80% is achieved. | 1975 | 237535 |
| kinetic study of the hydrolysis of lecithin monolayers by crotalus adamanteus alpha-phospholipase a2. monomer--dimer equilibrium. | 1975 | 1133380 | |
| postitional specificity of fatty acids in pyrophosphatidic acid from cryptococcus neoformans. | pyrophosphatidic acid isolated from cryptococcus neoformans was degraded to phosphatidic acid in aqueous pyridine. the phosphatidic acid was hydrolyzed by phospholipase a (ec 3.1.1.4) of crotalus adamanteus to lysophosphatidic acid and 2-positioned fatty acids. from the analyses of the fatty acid composition of pyrophosphatidic acid and its degraded products (phosphatidid acid, lysophosphatidic acid, and fatty acid), it was concluded that most of the saturated fatty acids of pyrophosphatidic a ... | 1975 | 168186 |
| organization of phospholipids in human red cell membranes as detected by the action of various purified phospholipases. | 1. the action of eight purified phospholipases on intact human erythrocytes has been investigated. four enzymes, e.g. phospholipases a2 from pancreas and crotalus adamanteus, phospholipase c from bacillus cereus, and phospholipase d from cabbage produce neither haemolysis nor hydrolysis of phospholipids in intact cells. on the other hand, both phospholipases a2 from bee venom and naja naja cause a non-haemolytic breakdown of more than 50% of the lecithin, while sphingomyelinase c from staphyloco ... | 1975 | 169915 |
| relation between various phospholipase actions on human red cell membranes and the interfacial phospholipid pressure in monolayers. | the action of purified phospholipases on monomolecular films of various interfacial pressures is compared with the action on erythrocyte membranes. the phospholipases which cannot hyorolyse phospholipids of the intact erythrocyte membrane, phospholipase c from bacillus cereus, phospholipase a2 from pig pancreas and crotalus adamanteus and phospholipase d from cabbage, can hydrolyse phospholipid monolayers at pressure below 31 dynes/cm only. the phospholipases which can hydrolyse phospholipids of ... | 1975 | 1174576 |
| phospholipase a2 as a probe of phospholipid distribution in erythrocyte membranes. factors influencing the apparent specificity of the reaction. | the action of snake venom phospholipases a2 in intact human erythrocytes was investigated in detail. the basis phospholipase from agkistrodon halys blomhifii was found to induce both hydrolysis of membrane phospholipids and total cell hemolysis under certain experimental conditions. the hydrolytic action of the basic enzyme was found to consist of two sequential events: (a) hydrolysis of 70% of the total cell ph osphatidylcholine without any evident hemolysis; and (b) complete hydrolysis of the ... | 1975 | 54 |
| kinetic study of the action of snake venom phospholipase a2 on human serum high density lipoprotein 3. | the hydrolysis of the phospholipids of intact human serum high density lipoprotein 3 (hdl3) by pure alpha-phospholipase a2 from crotalus adamanteus was studied by ph-stat titration. the enzyme quantitatively hydrolyzed phosphatidylcholine and phosphatidylethanolamine and left sphinogomyelin intact, yielding a stable and water-soluble modified hdl. lysophospholipids and free fatty acids, the products of hydrolysis, remained in the lipoprotein. when 1 mol of defatted bovine serum albumin/mol of su ... | 1976 | 5436 |
| vinylglycine and proparglyglycine: complementary suicide substrates for l-amino acid oxidase and d-amino acid oxidase. | proparglyglycine (2-amino-4-pentynoate) and vinylglycine (2-amino-3-butenoate) have been examined as substrates and possible inactivators of two flavo enzymes, d-amino acid oxidase from pig kidney and l-amino acid oxidase from crotalus adamanteus venom. vinylglycine is rapidly oxidized by both enzymes but only l-amino acid oxidase is inactivated under assay conditions. the loss of activity probably involves covalent modification of an active site residue rather than the flavin adenine dinucleoti ... | 1976 | 8082 |
| translocation and binding of adenine nucleotides by rat liver mitochondria partially depleted of phospholipids. | 1. rat liver mitochondria were partially depleted of their phospholipids using phospholipase a prepared from porcine pancreas (substrate specificity, cardiolipin greater than phosphatidylethanolamine greater than phosphatidylcholine) or from crotalus adamanteus venom (substrate specificity, phosphatidylethanolamine = phosphatidylcholine greater than cardiolipin). 2. removal of only about 1% of the mitochondrial phospholipid with the pancreatic enzyme leads to 50% and 25% losses in adp and atp tr ... | 1976 | 1259954 |
| positional and fatty acid specificity of monoacyl- and diacylglycerol 3-phosphate formation by rabbit heart microsomes. | fatty acid selectivity of acyl-coa:glycerol-3-phosphate acyltransferase (ec 2.3.1.15) and acyl-coa:monoacylglycerol-3-phosphate acyltransferase (ec 2.3.1.52) of the microsomal fraction prepared from rabbit heart was studied. 1. the rate of acylation of glycerol 3-phosphate was increased proportionally with the concentration of acyl-coa. the maximum rate was reached at 0.3 mumol acyl-coa per ml. palmitoyl-, oleoyl- and linoleoyl-coa all served equally well as acyl donors, and produced approximate ... | 1976 | 952977 |
| effects of local anaesthetics on phospholipases. | 1. the effects of six local anaesthetics have been studied on the activities of soluble phospholipases a2 (ec 3.1.1.4) and lysophospholipase (ec 3.1.1.5). 2. phospholipase a2 activity in human seminal plasma towards sonicated radioactively-labelled phosphatidylethanolamine was slightly stimulated a low and inhibited at high concentrations of all anaesthetic compounds employed. the order of decreasing potency was chlorpromazine, dibucaine, tetracaine, lidocaine, cocaine and procaine. in line with ... | 1976 | 952985 |
| characterization of a thrombin-like enzyme from crotalus adamanteus (eastern diamondback rattlesnake) [proceedings]. | 1976 | 1014024 | |
| enzymatic reactions of methionine sulfoximine. conversion to the corresponding alpha-imino and alpha-keto acids and to alpha-ketobutyrate and methane sulfinimide. | l-methionine sulfoximine is a substrate of l-amino acid oxidase (crotalus adamanteus), glutamine transaminase, and gamma-cystathionase. in the reaction catalyzed by l-amino acid oxidase, methionine sulfoximine is converted to aplph-imino-gamma-methylsulfoximinylbutyrate, which undergoes rapid gamma elimination yielding methane sulfinimide and 2-imino-3-butenoic acid. methane sulfinimide is converted to methane sulfonamide, methane sulfinic acid, and methane sulfonic acid; 2-imino-3-butenoic acid ... | 1976 | 977592 |
| an endonuclease activity of venom phosphodiesterase specific for single-stranded and superhelical dna. | a homogeneous preparation of venom phosphodiesterase from crotalus adamanteus possesses an intrinsic endonuclease activity, specific for superhelical (form i) and single-stranded dna. the phosphodiesterase degrades single-stranded t7 dna by endonucleolytic cleavages. duplex t7 dna is hydrolyzed by the liberation of acid-soluble products simultaneously from the 3' and 5' termini but without demonstrable internal scissions in duplex regions. since venom phosphodiesterase is known to hydrolyze olig ... | 1977 | 200616 |
| amino acid sequence of phospholipase a2-alpha from the venom of crotalus adamanteus. a new classification of phospholipases a2 based upon structural determinants. | the complete amino acid sequence of crotalus adamanteus venom phospholipase a2-alpha has been determined by analysis of the five tryptic peptides from the citraconylated, reduced, and s-[14c]carboxamidomethylated enzyme. earlier studies (tsao, f. h. c., keim, p. s., and heinrikson, r. l. (1975) arch. biochem. biophys. 167, 706) provided the information necessary to align the tryptic fragments so that secondary cleavage procedures to establish overlaps were unnecessary. the subunit in the phospho ... | 1977 | 873920 |
| thrombin-like enzyme from the venom of crotalus adamanteus (eastern diamondback rattlesnake). | 1977 | 854881 | |
| heterogeneity of exonuclease from the venom of crotalus adamanteus. | 1977 | 912500 | |
| search for relationships among the hemolytic, phospholipolytic, and neurotoxic activities of snake venoms. | several snake venom neurotoxins are larger and more complex than the well-studied group of postsynaptic toxins exemplified by alpha-bungarotoxin. several of these, exemplified by beta-bungarotoxin, show phospholipase a2 activity (phosphatide 2-acylhydrolase, ec 3.1.1.4) when tested in the presence of detergents. the high hemolytic activity of crotoxin, the neurotoxin of crotalus durissus terrificus, in the presence of lecithin has been attributed to this activity. the phospholipase a2 activity o ... | 1978 | 273221 |
| low concentrations of indomethacin inhibit phospholipase a2 of rabbit polymorphonuclear leukocytes. | inhibition of prostaglandin synthesis by indomethacin, a drug with anti-inflammatory properties, has been attributed to its action on fatty acid cyclooxygenase. however, prostaglandin synthesis would also be inhibited if precursor fatty acids were not supplied. we find that indomethacin inhibits phospholipase a2 (phosphatide 2-acylhydrolase, ec 3.1.1.4) of rabbit polymorphonuclear leukocytes in dose-dependent fashion. inhibition is immediate and readily detected at 1 micrometer. the extent of in ... | 1978 | 275865 |
| purification and some properties of two proteinases from crotalus adamanteus venom that inactivate human alpha 1-proteinase inhibitor. | two proteinases (proteinases i and ii) have been purified from crotalus adamanteus venom to the stage of electrophoretic homogeneity and proteinase ii has been crystallized. the proteinase differ slightly in molecular weight and amino acid composition. both are metalloenzymes requiring zn2+ or ca2+, or both; neither requires thiol compounds for activation. the proteinases are free of esterolytic activity against benzoly-l-arginine ethyl ester and benzoyl--tyrosine ethyl ester. proteinase ii clea ... | 1978 | 309470 |
| characterization of the inactive fragment resulting from limited proteolysis of human alpha1-proteinase inhibitor by crotalus adamanteus proteinase ii. | the inactive 50,000-dalton fragment of human plasma alpha1-proteinase inhibitor resulting from limited proteolysis of the inhibitor by crotalus adamanteus proteinase ii has been isolated and partially characterized. the amino acid composition of the inactivated inhibitor indicates the loss of a peptide fragment from the intact inhibitor. both intact and inactivated inhibitor contain cooh-terminal lysine. however, the nh2 terminus of the intact inhibitor is glx, whereas that of inactivated inhibi ... | 1979 | 447652 |
| trans fatty acids: positional specificity in brain lecithin. | fifteen-day-old rats were divided into three groups: one group received an intracerebral injection of 5 microci of 9-trans,12-trans [1-(14)c] octadecadienoic acid; the second group was given 5 microci of the same compound plus an equal wt of nonradioactive all cis arachidonic acid; the third group was given 5 microci of 9-trans [1-(14)c] octadecenoic acid. all animals were sacrificed 8 hr after injection. glycerophosphocholine (gpc) was isolated and partically deacylated with phospholipase a2 fr ... | 1979 | 449627 |
| in vitro actions of some antibiotics on phospholipases. | the effects of some antibiotics on activities of phospholipase a2, b and c were investigated in vitro. tetracyclines, macrolides, chloramphenicol and carbenicillin inhibited the activity of crotalus adamanteus phospholipase a2 towards phospholipids of egg-yolk emulsions. when the ability to inhibit the activity of penicillium notatum phospholipase b towards mixed micelles of phosphatidylcholine and triton x-100 was investigated, polymyxin b was found to be inhibitory while chloramphenicol and ca ... | 1979 | 541266 |
| effect of purified phospholipases on the binding of tetrodotoxin to axon plasma membrane. | the role of phospholipids in the binding of [3h]tetrodotoxin to garfish olfactory nerve axon plasma membrane was studied by the use of purified phospholipases. treatment of the membranes with low concentrations of either phospholipase a2 (crotalus adamanteus and naja naja) or phospholipase c (bacillus cereus and clostridium perfringens) resulted in a marked reduction in tetrodotoxin binding activity. a 90% reduction in the activity occurred with about 45% hydrolysis of membrane phospholipids by ... | 1979 | 39172 |
| crystalline basic protein from venom of crotalus adamanteus. | 1979 | 1145639 | |
| incorporation of 3h from delta-(l-alpha-amino (4,5-3h)adipyl)-l-cysteinyl-d-(4,4-3h)valine into isopenicillin n. | 1. delta-(l-alpha-amino[4,5-3h]adipyl)-l-cysteinyl-d-[4,4-3h]valine has been synthesized from its constituent amino acids, the l-alpha-amino[4,5-3h]adipic acid being obtained by reduction with 3h2 of methyl 5-acetamido-5,5-diethoxycarbonylpent-2-enoate and subsequent decarboxylation and hydrolysis. 2. in a cell-free system prepared by lysis of protoplasts of cephalosporium acremonium 3h was incorporated from the doubly labelled tripeptide into a compound that behaved like penicillin n or isopeni ... | 1979 | 575040 |
| a new method for purification of the thrombin-like enzyme from the venom of the eastern diamondback rattlesnake. | 1979 | 505414 | |
| venom exonuclease. ii. amino acid composition and carbohydrate, metal ion and lipid content in the crotalus adamanteus venom exonuclease. | exonuclease from crotalus adamanteus venom has only threonine as n-terminimal amono acid residue. it was examined for its amino acid composition, -sh and s-s groups. it has no free -sh groups and seven s-s bonds. the analysis of the carbohydrate residues in the enzyme proves that it is a glycoprotein. it contains neutral sugars (9.2%), amino sugars (1.9%) and ten sialic acid residues per molecule. the venom exonuclease is a metalloenzyme. this is proven by the existence of mg2+, zn2+ and ca2+ an ... | 1980 | 6246960 |
| defibrination syndrome following bites by the eastern diamondback rattlesnake. | 1980 | 7351526 | |
| studies on the complex between human alpha 2-macroglobulin and crotalus adamanteus proteinase ii. release of active proteinase from the complex. | proteinase ii from crotalus adamanteus venom formed a complex with human alpha 2-macroglobulin in which approx. 1.7 mol of enzyme were bound per mol inhibitor. the complex did not enzymatically inactivate human alpha 1 proteinase inhibitor. however, active proteinase ii was released from the complex in the presence of a high molecular weight proteinase fraction from c. adamanteus venom. the alpha 2-macroglobulin-proteinase ii complex was also unstable during incubation in serum, and the enzyme r ... | 1980 | 6160877 |
| uptake of phospholipid-depleted chylomicrons by the perfused rat liver. | 1. rat lymph chylomicrons were depleted of their surface phospholipids by treatment with pure phospholipase a2 from crotalus adamanteus venom. 2. about 80% of the phospholipids could be removed from the chylomicrons without any apparent effect on their size, neutral lipid composition or qualitative profile of their tetramethylurea-soluble apoproteins. 3. phospholipid-depleted chylomicrons were rapidly taken up whole by liver cells when perfused through isolated rat liver preparations. the rate o ... | 1980 | 7236241 |
| phospholipase a2 activity on mixed lipid monolayers: inhibition and activation of phospholipases a2 from porcine pancreas and crotalus adamanteus by anionic and neutral amphiphiles. | 1981 | 7325675 | |
| identification of the cleavage sites resulting from enzymatic inactivation of human antithrombin iii by crotalus adamanteus proteinase ii in the the presence and absence of heparin. | 1981 | 7034776 | |
| venom exonuclease. iii. immunochemical characterization and modification by specific antibody. | the immunoelectrophoretic purity of the exonuclease preparation, isolated from crotalus adamanteus venom according to a procedure previously published (dolapchiev, l.b., sulkowski, e. and laskowski, m., sr. (1974) biochem. biophys. res. commun. 61, 271-281), is reported. the enzyme showed one precipitin line against antibody prepared against partially purified venom. the exonuclease is unstable in dilute (1.25 microgram/ml and below) solutions. bovine serum albumin stabilized the enzyme nonspeci ... | 1981 | 6163475 |
| modification of the tetrodotoxin receptor in electrophorus electricus by phospholipase a2. | the effects of phospholipase a2 treatment on the tetrodotoxin receptors in electrophorus electricus was studied. (1) the binding of [3h]tetrodotoxin to electroplaque membranes was substantially reduced by treatment of the membranes with low concentrations of phospholipase a2 from a number of sources, including bee venom, vipera russelli and crotalus adamanteus and by beta-bungarotoxin. (2) phospholipase a2 from bee venom and from c. adamanteus both caused extensive hydrolysis of electroplaque me ... | 1981 | 6268164 |
| early management of bites by the eastern diamondback rattlesnake (crotalus adamanteus): studies in monkeys (macaca fascicularis). | monkeys were injected subcutaneously with 6 mg of crotalus adamanteus venom and a solid phase radioimmunoassay was used to measure levels of venom in plasma and urine. when no attempt was made to retard venom movement from the site of injection, plasma levels as high as 1,300 ng/ml occurred within 15 min of injection and progressive swelling developed in the injected limb. when first aid was employed (firm pressure to the injection site and immobilization of limb with a splint), plasma levels re ... | 1981 | 7235137 |
| the stereochemical course of hydrolysis catalysed by snake venom 5'-nucleotide phosphodiesterase. | adenosine 5'-(s)-[16o,17o,18o]phosphate was pyrophosphorylated by the combined action of adenylate kinase and pyruvate kinase. the isotopomers of adenosine 5'-[alpha-16o,17o,18o]triphosphate were hydrolysed by venom 5'-nucleotide phosphodiesterase (crotalus adamanteus) in h2(17)o. analysis by 31p nuclear magnetic resonance spectroscopy of the resulting adenosine 5'-[16o,17o,18o]phosphate, after cyclization and esterification, showed that the hydrolysis occurs with retention of configuration at p ... | 1981 | 6280670 |
| a further examination of the active form of crotalus adamanteus phospholipase a2. | the phospholipase a2 from crotalus adamanteus venom has been shown to be active as the dimer or 30 000 molecular weight species, at concentrations used for enzyme assay (0.1--10 microgram/ml). gel filtration of the enzyme in the presence of ca2+ and monomeric concentrations of the substrate dihexanoylphosphatidylcholine showed that all the protein migrated as a 30 000 molecular weight species. active enzyme sedimentation velocity experiments using the same conditions gave s020,w=2.85 +/- 0.05 s, ... | 1981 | 7225406 |
| fibrinolytic and fibrinogen clotting enzymes present in the venoms of western diamondback rattlesnake, crotalus atrox, eastern diamondback rattlesnake, crotalus adamanteus, and southern pacific rattlesnake, crotalus viridis helleri. | 1981 | 7222089 | |
| impairment of platelet aggregation by echis colorata venom mediated by l-amino acid oxidase or h2o2. | echis colorata bites cause impairment of platelet aggregation and hemostatic disorders. the mechanism by which the snake venom inhibits platelet aggregation was studied. upon fractionation, aggregation impairment activity and l-amino acid oxidase activity were similarly separated from the crude venom, unlike other venom enzymes. preparations of l-amino acid oxidase from e. colorata and from crotalus adamanteus replaced effectively the crude e. colorata venom in impairment of platelet aggregation ... | 1982 | 7164017 |
| differential inhibitory effects by phospholipase a2 on guanylate and adenylate cyclases of tetrahymena plasma membranes. | phospholipid composition of tetrahymena plasma membranes was modified by phospholipase a2-treatment and its effects on the activities of the two membrane-bound cyclases (adenylate and guanylate) were studied. phospholipase a2 from crotalus adamanteus was found to hydrolyze preferentially phosphatidylethanolamine of isolated plasma membranes. in the phospholipase a2-treated membranes in which 45% of total phosphatidylethanolamine was converted to its lysolipid, adenylate cyclase activity was to a ... | 1982 | 6129336 |
| kallikrein-like activity of crotalase, a snake venom enzyme that clots fibrinogen. | during the amino acid sequence determination of crotalase (ec 3.4.21.30), the thrombin-like enzyme from the venom of crotalus adamanteus (eastern diamondback rattlesnake), we found that, in addition to the expected structural homology with bovine thrombin (ec 3.4.21.5), there was even greater homology with porcine pancreatic kallikrein (ec 3.4.21.8). in exploring further the similarities between crotalase and kallikrein, several striking observations were made. first, crotalase was rapidly and s ... | 1982 | 7043462 |
| local necrotizing effect of snake venoms on skin and muscle: relationship to serum creatine kinase. | twenty-five snake venoms were tested for their ability to induce an increase of serum creatine kinase (ck) level after i.m. injection (0.125-1.0 mg/kg) into rates. of six australian elapid venoms only those from pseudechis colletti guttatus and p. australis produced a steep rise of ck-activity (30-70 times the normal value) 4 and 16 hr after injection (0.5 mg/kg). viperid and crotalid venoms had only slight effects (2-5 times the normal value) even in doses of 1.0 mg/kg except for a sample of cr ... | 1983 | 6623487 |
| facilitation of phospholipase a2 activity by mastoparans, a new class of mast cell degranulating peptides from wasp venom. | the effect of mastoparan, ile-asn-leu-lys-ala-leu-ala-ala-leu-ala-lys-lys-ile-leunh2, and related peptides on the release of arachidonic acid from egg yolk lecithin liposomes, rat peritoneal mast cells, and cultured human fibroblasts was studied. in unsonicated liposomes, labeled with 1-stearoyl-2[1-14c]arachidonyl-sn-glycero-3-phosphocholine, 5 x 10(-5) m mastoparan caused a 12-, 15-, and 50-fold increase in the production of arachidonic acid catalyzed by phospholipase a2 from bee venom, easter ... | 1983 | 6643447 |
| phospholipids chiral at phosphorus. preparation and spectral properties of chiral thiophospholipids. | the thiophospholipid 1,2-dipalmitoyl-sn-glycero-3-thiophosphocholine (dppsc) was shown to be a mixture of two diastereomers by 31p nuclear magnetic resonance. the isomer that resonates at the lower field in cdcl3 (56.12 ppm) was designated as isomer a and the other (resonates at 56.07 ppm) as isomer b. phospholipase a2 from four different sources (bee venom, naja naja venom, crotalus adamanteus venom, and porcine pancreas) was shown to hydrolyze the isomer b of dppsc specifically, whereas phosph ... | 1983 | 6688028 |
| mechanism of defibrination in humans after envenomation by the eastern diamondback rattlesnake. | we prospectively studied the hemostatic system of ten persons bitten by the eastern diamondback rattlesnake (crotalus adamanteus) during 1978-1980. blood was drawn when the patients arrived in the emergency room and every 6 hr thereafter. all envenomated victims developed incoagulable blood (defined by a thrombin time greater than or equal to 120 sec, normal less than 20 sec). platelet counts and plasma levels of antithrombin iii and factors ii and viii were not drastically altered, which distin ... | 1983 | 6859033 |
| kallikrein-like enzymes from crotalus atrox venom. | the symptoms which immediately follow envenomation by many crotalid snakes include hypotension, hypovolemia, hemoconcentration, and shock. we have isolated and characterized two proteases (ei and eii) from the venom of crotalus atrox which may be involved in the onset of these symptoms. ei and eii have molecular weights of 27,500 and 29,200 and isoelectric points of 4.7 and 4.3, respectively. specific esterolytic activities of ei and eii on n alpha-p-tosyl-l-arginine methyl ester are 51.5 mumol ... | 1983 | 6355088 |
| venom exonuclease. iv. intrinsic fluorescence of the exonuclease from crotalus adamanteus venom. | the intrinsic fluorescence of the exonuclease isolated from crotalus adamanteus venom, was studied. the position of its maximum at 335 nm and half-width of the emission band 55 nm (lambda exc. 295 nm) suggested the existence of at least two types of tryptophan residues in the enzyme molecule. differential analysis of the fluorescence spectra obtained by excitation at 280 and 295 nm revealed about 12.5% contribution of the tyrosine fluorescence in the overall emission excited at 280 nm. the envir ... | 1983 | 6306968 |
| intraspecific variation in content of a basic toxin in eastern diamondback rattlesnake (crotalus adamanteus) venom. | venom samples from four specimens of crotalus adamanteus from the same litter were analyzed for the content of a basic toxin by gel filtration. whereas the venoms of two snakes were essentially free of the toxin, two other contained about 5% and 11% toxin (w/w). the individual absence or presence of the toxin in the venom was constant, suggesting a genetically determined variation. | 1984 | 6523512 |
| properties of the arginine esterases from bitis nasicornis (horned adder) venom. | five forms of arginine esterase (de-2 to de-6) were purified from bitis nasicornis venom by gel filtration on sephadex g-50, followed by ion exchange chromatography on cm-cellulose and deae-sepharose. they contain 17.6 to 23.1% of carbohydrate, 242 to 244 amino acids including 14 half-cystine residues and have molecular masses of about 38 kda. the enzymes have a high esterolytic activity towards n alpha-benzoyl-l-arginine ethyl ester but show no proteolytic activity against azocoll and no clotti ... | 1984 | 6569850 |
| a simple and versatile affinity column for phospholipase a2. | an affinity adsorbent for phospholipase a2 (ec 3.1.1.4) was prepared by reacting 10-o-p-toluenesulfonyldecane-1-o-phosphocholine with ah-sepharose 4b. phospholipases a2 bind to the immobilized ligand in the presence of ca2+ and can be eluted with buffers containing edta. this principle held not only for soluble phospholipase a2 from porcine pancreas and crotalus adamanteus, but proved also effective in the purification of phospholipases a2 solubilized from the membranes of rat liver mitochondria ... | 1984 | 6421328 |
| conversion of 6-mercaptopurine to 6-thioguanylic acid in l-1210 cells and human leukemia cells. | the metabolism of 6-mercaptopurine (6-mp) in l-1210 mouse leukemia cells and human chronic myelocytic leukemia cells (cml cells) was examined. the acid-soluble fractions obtained from cells incubated with [8-14c]6-mp were chromatographed on a dowex-1 formate resin column using a formic acid linear gradient elution system. chromatography of the extract of l-1210 cells revealed four principal radioactive peaks. the fraction containing the third peak was hydrolyzed by snake venom 5'-nucleotidase (c ... | 1985 | 2858424 |
| determination of the protein content of crystals formed by mastigocladus laminosus c-phycocyanin, chroomonas spec. phycocyanin-645 and modified human fibrinogen using an improved ficoll density gradient method. | we demonstrated for several protein crystals of known protein content that the simple ficoll density gradient method for crystal density determination as described by westbrook (1976) often leads to quite erroneous results. in particular, the apparent density of loosely packed crystals can show a tremendous change within the first minutes of measurement. in order to derive the correct protein content the apparent crystal density must be followed as a function of time and has to be extrapolated b ... | 1985 | 3924073 |
| aggregation studies on fluorescein-coupled cobra venom phospholipase a2. | phospholipase a2 from naja naja naja venom (indian cobra) undergoes a concentration-dependent aggregation, and at an assay concentration of 1 microgram ml-1, it exists as a monomer. however, there is some evidence that the enzyme is actually active as a dimer or higher order aggregate. previous attempts to determine the aggregation state of the enzyme under actual assay conditions were thwarted by experimental difficulties due in part to the low enzyme concentrations required. this aggregation h ... | 1985 | 3936540 |
| activation, aggregation, and product inhibition of cobra venom phospholipase a2 and comparison with other phospholipases. | the kinetics of phospholipid hydrolysis by cobra venom phospholipase a2 were examined and compared to those of phospholipase a2 from porcine pancreas, crotalus adamanteus (rattlesnake) venom, and bee venom. only the enzyme from naja naja naja (cobra) venom was found to be activated significantly by phosphorylcholine-containing compounds when hydrolyzing phosphatidylethanolamine. the cobra venom enzyme was also the only one in which these activators induced protein aggregation. the parallel speci ... | 1985 | 4030786 |
| biosynthetic incorporation of cis-parinaric acid into radioactive sn-3-phosphatidic acid. | isolated guinea pig liver microsomal membranes catalyzed the incorporation of naturally occurring cis-parinaric acid into sn-3-[u-14c]glycerophosphate. this resulted in the formation of sn-3-[14c](parinaroyl)phosphatidic acid, which was isolated by chelex-100 and deae-cellulose column chromatography and further purified by sephadex-g 25. the sn-3-[14c](parinaroyl)phosphatidic acid thus obtained exhibited absorption and fluorescence spectra substantially different from the cis-parinaric acid. dis ... | 1985 | 4034509 |
| purification and partial characterization of the hemorrhagic factor from the venom of crotalus adamanteus (eastern diamondback rattlesnake). | a proteinase from crotalus adamanteus venom has been isolated to the stage of electrophoretic homogeneity by chromatography of the crude venom on cm-sepharose, phenyl-sepharose, ultrogel aca 44 and deae-sepharose. the proteinase accounts for 100% of the detectable hemorrhagic activity in the venom, and the name c. adamanteus proteinase h is suggested. proteinase h is a single chain glycoprotein with a molecular weight of 85,700. proteinase h is active on casein and hide powder azure, but does no ... | 1985 | 2414864 |
| two new inhibitors of phospholipase a2 produced by penicillium chermesinum. taxonomy, fermentation, isolation, structure determination and biological properties. | plastatin and the known fungal metabolite, luteosporin, have been isolated from fermentations of penicillium chermesinum as inhibitors of porcine pancreatic phospholipase a2 (pla2). structure 1 for plastatin was deduced from its spectroscopic properties. plastatin and luteosporin inhibited pancreatic pla2 competitively with ki values of 0.89 microm and 12.8 microm, respectively. pla2 preparations from naja naja and crotalus adamanteus were not significantly inhibited by plastatin and luteosporin ... | 1985 | 3839502 |
| purification and partial characterization of a high molecular weight metalloproteinase from the venom of crotalus adamanteus (eastern diamondback rattlesnake). | chromatography of crotalus adamanteus venom on cm-sepharose, cibacron blue-sepharose and phenyl-sepharose, followed by gel filtration on ultrogel aca 44, has resulted in the isolation in homogeneous condition of a metalloproteinase active on casein and hide powder azure. the proteinase has an alkaline isoelectric point, and the trivial name proteinase b ('basic proteinase') is suggested to distinguish it from previously characterized c. admanteus metalloproteinases. proteinase b is a single chai ... | 1985 | 3911494 |
| comparison of two methods for proteolytic enzyme detection in snake venom. | an acrylamide gel system containing fibrinogen was used to detect proteolytic enzymes in snake venoms. proteolytic activity was observed as a clear area on a blue background after electrophoresis and overnight incubation in tris buffer, prior to staining with coomassie blue. venoms from eastern and western diamondback and west coast mexican rattlesnakes, crotalus adamanteus, c. atrox and c. basiliscus basiliscus, respectively, and southern copperhead, agkistrodon contortrix contortrix, were anal ... | 1986 | 3087029 |
| a complete amino acid sequence for the basic subunit of crotoxin. | the complete amino acid sequence of the basic subunit of crotoxin from the venom of crotalus durissus terrificus has been determined. fragmentation of the protein was achieved by using cyanogen bromide and arginine- and lysine-specific endoproteases. sixteen glx and asx residues reported by fraenkel-conrat et al. (1980) in natural toxins (d. eaker and t. wadstrom, eds.), pp. 561-567, pergamon, oxford.) have been resolved as glu or gln and asp or asn residues, respectively. most of the remaining ... | 1986 | 3753003 |
| cross-reactivity and neutralization by rabbit antisera raised against crotoxin, its subunits and two related toxins. | antisera were raised against intact crotoxin (crotalus durissus terrificus), mojave toxin (crotalus scutulatus scutulatus) and concolor toxin (crotalus viridis concolor), as well as the subunits of crotoxin. double immunodiffusion and enzyme-linked immunosorbent assays (elisa) demonstrated antigenic similarity between these three purified toxins and their subunits. additionally, when crotoxin antisera were pre-incubated with each of the three toxins before injection, the lethal activity of all w ... | 1986 | 3095955 |
| amino acid sequence of trimeresurus flavoviridis phospholipase a2. | the amino acid sequence of phospholipase a2 from the venom of trimeresurus flavoviridis (the habu snake) was determined. the enzyme subunit has a molecular weight of 13,764 and consists of a single polypeptide chain of 122 amino acids and seven disulfide bonds. the fragmentation was conducted by digesting the reduced and s-carboxymethylated derivative of the protein with achromobacter protease i, chymotrypsin, and trypsin, respectively. achromobacter protease i peptides were used for alignment a ... | 1986 | 3514593 |
| helodermatine, a kallikrein-like, hypotensive enzyme from the venom of heloderma horridum horridum (mexican beaded lizard). | we have purified and characterized the major n-benzoyl-l-arginine ethyl ester hydrolase from the venom of heloderma horridum horridum. the enzyme belongs to the serine proteinase family, and its activity vs. peptide amide substrates and human high-molecular-weight kininogen suggests a similarity to the family of kallikreins. this interpretation is corroborated by its reactivity with the natural inhibitors soybean trypsin inhibitor and kunitz-type bovine pancreatic trypsin inhibitor (aprotinin). ... | 1986 | 3537191 |
| antitumor action of crotalase, a defibrinogenating snake venom enzyme. | recent reports have shown that malignant cells release a variety of factors that modulate the tumor microenvironment. these factors, after release or shedding, work in concert to produce extravasation of fibrinogen from surrounding blood vessels with subsequent fibrin deposition around the tumor cells. this fibrin deposit could act to mask the tumor from the host's immune surveillance system. fibrin deposits have been observed by investigators in the vicinity of various malignant tumors of man a ... | 1986 | 3538422 |
| the action of various venoms on escherichia coli. | the antibacterial activity of honeybee venom (apis mellifera), three snake venoms (naja naja sputatrix, vipera russellii and crotalus adamanteus) and the polypeptide melittin was investigated against escherichia coli. minimum inhibitory concentration values, cell lysis and alterations in cell permeability were determined and action against e. coli was in the order: a. mellifera venom greater than melittin greater than n. naja sputatrix venom much greater than v. russellii venom greater than c. a ... | 1986 | 3542922 |