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1.
1. A marine hyaluronidase was purified 261-fold from the stonefish (Synanceja horrida) crude venom using Sephacryl S-200 HR and heparin affinity-gel chromatography. 2. Stonefish hyaluronidase has a pI of 9.2, a mol. wt of 62,000 and it was purified to a very high spec. act. of 1.6 x 10(6) NFU/mg protein. 3. It was heat sensitive and was inhibited by Cu2+, Hg2+ and heparin. 4. Stonefish hyaluronidase did not contain any haemorrhagic or lethal activity. 5. The N-terminal sequence of stonefish hyaluronidase has been determined to be A-P-S-X-D-E-G-N-K-K-A-D-N-L-L-V-K-K-I-N.  相似文献   

2.
Crystals of stonustoxin have been obtained and diffract to 3.4 A resolution. Stonustoxin is a protein lethal factor isolated from the venom of the stonefish, Synanceja horrida. The crystals belong to the tetragonal space group P422, with unit cell constants a = b = 109.0 A, c = 245.7 A. A native stonustoxin molecule has two subunits, designated alpha and beta, respectively, and there is one stonustoxin molecule per asymmetric unit.  相似文献   

3.
Yew WS  Khoo HE 《Biochimie》2000,82(3):251-257
Stonustoxin (SNTX) is a pore-forming cytolytic lethal factor, isolated from the venom of the stonefish Synanceja horrida, that has potent hemolytic activity. The role of tryptophan residues in the hemolytic activity of SNTX was investigated. Oxidation of tryptophan residues of SNTX with N-bromosuccinimide (NBS) resulted in loss of hemolytic activity. Binding of 8-anilino-1-naphthalenesulphonate (ANS) to SNTX resulted in occlusion of tryptophan residues that resulted in loss of hemolytic activity. Circular dichroism and fluorescence studies indicated that ANS binding resulted in a conformational change of SNTX, in particular, a relocation of surface tryptophan residues to the hydrophobic interior. NBS-modification resulted in oxidised surface tryptophan residues that did not relocate to the hydrophobic interior. These results suggest that native surface tryptophan residues play a pivotal role in the hemolytic activity of STNX, possibly by being an essential component of a hydrophobic surface necessary for pore-formation. This study is the first report on the essentiality of tryptophan residues in the activity of a lytic and lethal factor from a fish venom.  相似文献   

4.
Some biological and neurochemical properties of the venom of stonefish (Syanceja horrida) were investigated. The venom exhibited oedema-inducing, haemolytic, hyaluronidase, thrombin-like, alkaline phosphomonoesterase, 5' nucleotidase, acetylcholinesterase, phosphodiesterase, arginine esterase, and arginine amidase activities. Recalcification clotting time, prothrombin, and kaolin-cephalin clotting times were increased 1.7-2.3- and 2.4-fold respectively. The LD50 (i.v. mouse) was 300 micrograms/Kg. Its effects on uptake and stimulation of neurotransmitter synthesis and release were observed in rat brain synaptosomes. In the presence of 100 micrograms venom, uptake of [methyl-3H] choline in rat brain synaptosomes was inhibited 70%, while that of 4-amino-n-[U-14C] butyric acid was inhibited 20%. The toxin also stimulated the release of [3H]-acetylcholine from the synaptosomes.  相似文献   

5.
Liew HC  Khoo HE  Moore PK  Bhatia M  Lu J  Moochhala SM 《Life sciences》2007,80(18):1664-1668
Stonustoxin (SNTX) is a 148 kDa, dimeric, hypotensive and lethal protein factor isolated from the venom of the stonefish Synanceja horrida. SNTX (10-320 ng/ml) progressively causes relaxation of endothelium-intact, phenylephrine (PE)-precontracted rat thoracic aortic rings. The SNTX-induced vasorelaxation was inhibited by L-N(G)-nitro arginine methyl ester (L-NAME), suggesting that nitric oxide (NO) contributes to the SNTX-induced response. Interestingly, D, L-proparglyglycine (PAG) and beta-cyano-L-alanine (BCA), irreversible and competitive inhibitors of cystathionine-gamma-lyase (CSE) respectively, also inhibited SNTX-induced vasorelaxation, indicating that H(2)S may also play a part in the effect of SNTX. The combined use of L-NAME with PAG or BCA showed that H(2)S and NO act synergistically in effecting SNTX-induced vasorelaxation.  相似文献   

6.
Anticomplement factor (cobra venom factor) from the venom of Naja naja atra was purified by means of successive chromatography on DEAE-cellulose, Sephadex G-200 and Sepharose CL-6B. The purified anticomplement factor was homogeneous as judged by polyacrylamide discontinuous gel electrophoresis at pH 9.4. The yield from 3.0 g of the crude venom was approx. 28 mg. The molecular weight was estimated to be about 156 000 by SDS-polyacrylamide gel electrophoresis. The isoelectric point was about 5.2. SDS-polyacrylamide gel electrophoresis of the anticomplement factor in the presence of dithiothreitol demonstrated that the molecule possesses three different polypeptide chains cross-linked covalently to one another by disulfide bridge(s). By SDS-polyacrylamide gel electrophoresis, the molecular weight of each subunit was determined to be approx. 77000, 47500 and 29 000, respectively. All subunits were stained with Coomassie brilliant blue G-250 and periodate-Schiff reagent, indicating these subunits to be glycoprotein. Distribution of the anticomplement factor in various snake venoms, which shows cross-reactivity against the anti-Naja naja atra anticomplement factor antiserum, was examined. From the results, all venoms belonging to cobra family in the Elapidae tested so far were found to contain such cross-reactivity.  相似文献   

7.
The nerve growth factor (NGF) from Naja naja (cobra) venom has been purified and its structure compared to the NGF from mouse submaxillary gland. A two-step purification procedure has been devised, consisting of a gel filtration step in 1 M acetic acid followed by chromatography of the active pool on carboxymethylcellulose at pH 5. The molecular weight of the native protein was found to be 28000, and this value was reduced by approximately one-half under denaturing conditions. These values are comparable to those obtained for mouse 2.5S or betaNGF. Tryptic peptide maps of S-[14C]carboxymethyl NGF gave the number of labeled peptides expected for a structure composed of two identical or very similar subunits. Thus, the quaternary structures of mouse and cobra NGF are the same. Cyanogen bromide (CNBr) treatment of Naja naja NGF produced three fragments, of which two were purified to homogeneity. These fragments and the whole protein were analyzed in the automated protein Sequencer. The amino-terminal CNBr fragment of the protein was also subjected to digestion by thermolysin and the resultant peptides were purified and characterized. These data plus those from the characterization of the tryptic peptides provided the basis of the construction of a tentative primary structure of Naja naja NGF which is approximately 60% identical with mouse NGF.  相似文献   

8.
Two proteins with phospholipase A(2) (PLA(2)) activity were purified to homogeneity from Bothrops leucurus (white-tailed-jararaca) snake venom through three chromatographic steps: Conventional gel filtration on Sephacryl S-200, ion-exchange on Q-Sepharose and reverse phase on Vydac C4 HPLC column. The molecular mass for both enzymes was estimated to be approximately 14 kDa by SDS-PAGE. The N-terminal sequences (48 residues) show that one enzyme presents lysine at position 48 and the other an aspartic acid in this position, and therefore they were designated blK-PLA(2) and blD-PLA(2) respectively. blK-PLA(2) presented negligible levels of PLA(2) activity as compared to that of blD-PLA(2). The PLA(2) activity of both enzymes is Ca(2+)-dependent. blD-PLA(2) did not have any effect upon platelet aggregation induced by arachidonic acid, ADP or collagen, but strongly inhibits coagulation and is able to stimulate Ehrlich tumor growth but not angiogenesis.  相似文献   

9.
A lethal toxin was isolated from the venom of Heloderma h. horridum by gel filtration and ion-exchange chromatography. Molecular weight of the purified toxin was determined to be 28 kDa under reducing and nonreducing conditions. Biological activity, assayed by i.v. routes of injection, shows an LD50 for this preparation of 0.135 micrograms/g. Additionally, the toxin possesses an inhibitory effect on direct electrical stimulation of the isolated mouse hemi-diaphragm. However, neither hemorrhagic nor hemolytic activities were detected. Phospholipase A2 activity, proteolytic activity and arginine esterolytic activity were absent. The amino acid composition of the lethal toxin and the NH2-terminal sequence up to residue number 33 were determined. Neither show similarities to other components from H. h. horridum venom.  相似文献   

10.
The nerve growth factor from Bungarus multicinctus venom was purified by means of successive chromatography on Sephadex G-50, carboxymethyl-cellulose, carboxymethyl-Sephadex C-50 and Sephadex G-50. The purified nerve growth factor was homogeneous by polyacrylamide disc gel electrophoresis. The molecular weight was estimated to be about 21 000 by gel filtration. Compared with the nerve growth factors from the venoms of other Elapidae, namely Naja naja and Naja naja atra, this protein showed high isoelectric point of approximately pH 10. A characteristic of the nerve growth factor of B. multicinctus venom is that the protein consisted of two subunits of equal molecular weight which are linked covalently to each other by a disulfide bridge. The purified B. multicintus nerve growth factor elicited its maximal neurite outgrowth from embryonic dorsal root ganglia at the concentration interval from 30 to 100 ng/ml.  相似文献   

11.
A procedure for the purification of phosphodiesterase from Crotalus venom on DEAE-cellulose at alkaline pH is described. The enzyme gives a single band in polyacrylamide gels and is free of contaminating nucleolytic enzymes. The molecular weight is about 115000. Concentration in an Amicon ultrafiltrator gave a highly concentrated active enzyme. Phosphodiesterase is relatively stable and can be stored at 4 degrees C in the presence of Mg2 and serum albumin for years. For the detection of contaminating endonuclease, an assay was used in which tRNA was the substrate and possible internal breaks were detected in polyacrylamide gel after denaturation. With bis(p-nitrophenyl) phosphate as substrate, 15mM Mg2 was necessary for optimal activity. The reaction remained linear for at least 15 min at 22 degrees C. At 45 degrees C, the liberation of p-nitrophenol was highest within 25 min of incubation. At 75 degrees C, inactivation of the enzyme occurred after 4 min.  相似文献   

12.
13.
Two polypeptides (designated DTX-A and DTX-B) were purified from crude snake venom of Dendroaspis angusticeps using gel filtration, cation exchange colum chromatography and cation exchange high performance liquid chromatography, and their blocking actions of K+ channels were investigated in rat brain synaptosomes. Both DTX-A and DTX-B inhibited the voltage-dependent 42K efflux from the synaptosomes. DTX-A blocked 42K efflux of both the rapidly inactivating phase (component T) and the slowly inactivating phase (component S). The inhibitory effect of DTX-A on component T was pronounced compared with that on component S. However, DTX-B selectively blocked 42K efflux of component S. The molecular weights of DTX-A and DTX-B were estimated to be ca 10,000 by SDS-polyacrylamide gel electrophoresis. The amino acid composition of these toxins is different from that of polypeptide purified from the venom of D. angusticeps (-, β, γ- and δ-DTX). These results suggest that DTX-A and DTX-B are new polypeptides which block voltage-dependent K+ channels selectively, and that they are useful tools for investigating the K+ channel.  相似文献   

14.
15.
A basic serine protease which is active on casein and fibrinogen was purified from Bothrops moojeni venom using a single step chromatography on a CM-Sepharose fast flow column. The enzyme, MOO3, was not hemorrhagic and presented only a trace of blood-clotting activity. Synthetic chromogenic substrates (azoacasein and azoalbumin) where not hydrolyzed by MOO3. Using polyacrylamide gel electrophoresis at pH 4.3, MOO3 showed as a single protein band. Using sodium dodecyl sulfate-polyacrylamide electrophoresis, MOO3 behaved as a single-chain protein with an approximate mol. weight of 27,000, both in the presence and absence of beta-mercaptoethanol. Its pI was 7.8 by electrofocusing. The enzyme did not contain neutral carbohydrates and its N-terminal amino acid was alanine. The amino acid composition showed 249 residues/mole, a high content of hydrophilic amino acids and 14 half-cystine residues, which should account for 7 disulfide bonds. The protease cleaved the A-alpha chain faster than the B-beta of bovine fibrinogen and showed no effect on the delta-chain. Specific esterolytic activity of MOO3 on alpha-N-tosyl-l-arginine methyl ester was 29.64 mumol min-1 x mg-1. MOO3 represented 1.42% (w/w) of the initial desiccated venom. Its proteolytic activity was inhibited by beta-mercaptoethanol, leupeptin, phenylmethylsulphonyl fluoride and ethylenediamine tetraacetate.  相似文献   

16.
Hyaluronidase from Propionibacterium acnes has been purified 13,000-fold from the culture supernatant to homogeneity (as determined by polyacrylamide disc gel electrophoresis). The molecular weight of the purified enzyme was 85,110 as determined by gel filtration. The purified enzyme had a pH optimum at 6.4, was stable between pH 5 and 5.8 and was completely inactivated after 15 min at 50 degrees C. Preliminary studies suggested that the enzyme is active against chondroitin 4- and 6-sulphates, but not against dermatan sulphate. Analysis by paper chromatography of the reaction products from the degradation of hyaluronic acid by bacterial, testicular and P. acnes enzymes suggested that the P. acnes enzyme is similar in its mode of action to other bacterial hyaluronate lyases. The enzyme from P. acnes may thus be tentatively classified as a hyaluronate lyase.  相似文献   

17.
delta-(L-alpha-Aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) was purified from Streptomyces clavuligerus by a combination of salt precipitation, ultrafiltration, and anion-exchange chromatography. The final purified material gave two protein bands with molecular weights of 283,000 and 32,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Electrophoresis in nondenaturing gels gave a single protein band with an estimated molecular weight of 560,000. These results suggest that ACVS is a multimer composed of nonidentical subunits.  相似文献   

18.
Cob(I)alamin adenosyltransferase (EC 2.5.1.17) was purified to homogeneity from extracts of a Pseudomonas denitrificans recombinant strain and sequenced at its N terminus. It is a homodimer (each unit with an Mr of 28,000) encoded by cobO. The enzyme adenosylated all of the corrinoids isolated from this microorganism but did not adenosylate cobyrinic acid.  相似文献   

19.
Hemorrhagic factor II (LHF-II) was isolated from Lachesis muta muta (Bushmaster snake) venom using column chromatographies on Sephadex G-100, CM-Sepharose CL-6B and two cycles on Sephadex G-50. This preparation was devoid of phospholipase A2 as well as of the enzymes active on arginine synthetic substrates (TAME and BAPNA) which are present in the crude venom. LHF-II was homogeneous by SDS-polyacrylamide gel electrophoresis, immunodiffusion and immunoelectrophoresis. Also, a single symmetrical boundary with a value of 2.59 S was obtained by ultracentrifugation. LHF-II contains 180 amino acid residues, has a molecular weight of 22,300, and an isoelectric point of 6.6. It contains one gatom zinc and two gatoms calcium per mol protein. The hemorrhagic factor possesses proteolytic activity toward various substrates such as, casein, dimethylcasein, hide powder azure, fibrinogen and fibrin. It hydrolyzes selectively the A alpha-chain of fibrinogen, leaving the B beta- and gamma-chains unaffected. LHF-II is activated by Ca2+ and inhibited by Zn2+. The hemorrhagic as well as the proteinase activity is inhibited by cysteine and by metal chelators such as EDTA, EGTA and 1,10-phenanthroline. Inhibitors of serine proteinases such as phenylmethanesulfonyl fluoride (PMSF) and soybean trypsin inhibitor (SBTI) have no effect on the hemorrhagic factor.  相似文献   

20.
Recombinant human differentiation-stimulating factor (rhD-factor) has been isolated to greater than 95% purity from Chinese hamster ovary cells. RhD-factor is a glycoprotein with an apparent molecular weight of 45.6 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. On gel filtration in 6 M guanidine-hydrochloride, rhD-factor elutes with an apparent molecular weight of 21.5 kDa; it elutes with an apparent molecular weight of 44.8 kDa under neutral pH (native) conditions. The amino-terminal sequence (12 residues) is consistent with the expected sequence derived from the genomic DNA sequence. Recombinant D-factor is heavily glycosylated with 30% by weight neutral sugar and 12% sialic acid. The ED50 for rhD-factor was 0.25 ng/ml. Trifluoromethanesulfonic acid-deglycosylated rhD-factor has a biological activity comparable to that of the native recombinant protein (ED50 = 0.40 ng/ml). The biological activity of rhD-factor was stable at pH 1 for 40 h, in 6 M guanidine-HCl containing buffers with or without reducing agent, and in 1% SDS. Carboxymethylation of D-factor after reduction totally destroyed biological activity.  相似文献   

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