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2.
Toxicon ; 30(8): 925-30, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1523685

RESUMO

We describe a procedure for molecular mass determination of hyaluronidases present in animal venoms from different families. Hyaluronidases can be revealed, following their electrophoretic separation in sodium dodecyl sulfate-polyacrylamide gel containing hyaluronic acid, by incubating the gel in Triton X-100 to remove sodium dodecyl sulfate and restore in situ enzyme activity. This method allows the detection of as little as 0.025 turbidity-reducing units after 2 hr incubation. All the hyaluronidases from the analyzed invertebrate venoms had a mass below 50,000 and showed only one component, while those from vertebrate venoms were more than 60,000 and in many instances contained more than one form.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Hialuronoglucosaminidase/análise , Peçonhas/química , Animais , Peso Molecular , Dodecilsulfato de Sódio , Peçonhas/enzimologia , Peçonhas/isolamento & purificação
3.
Toxicon ; 29(1): 119-24, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2028470

RESUMO

Dimethyl-DL-2,3-distearoyloxy-propyl-2'-hydroxy-ethylammonium++ + (Rosenthal's inhibitor) was coupled to carboxyhexyl-Sepharose 4B, through carbodiimide chemistry. Phospholipase A2 from Heloderma horridum horridum and Crotalus adamanteus bind to the immobilized ligand in the presence of Ca2+ and can be easily eluted under acidic conditions or in the presence of a chelating agent, respectively. This affinity media proved to be effective also in the purification of a Ca2(+)-independent phospholipase A1 from vespid venom.


Assuntos
Venenos de Crotalídeos/química , Lagartos , Fosfolipases A/isolamento & purificação , Peçonhas/química , Venenos de Vespas/química , Animais , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Ligantes , Fosfolipases A/antagonistas & inibidores , Fosfolipases A1 , Fosfolipases A2 , Sefarose , Estearatos
4.
Comp Biochem Physiol B ; 89(1): 153-61, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2451580

RESUMO

1. Several toxic polypeptides were found in the venom of the scorpion Centruroides limpidus limpidus. Comparative studies of the potency of the venom in different strains of mice were conducted. 2. A new type of toxin (component II.9), specific for crustaceans (crayfish and isopods), was isolated from this scorpion and was shown to have the following N-terminal amino acid sequence: Lys-Lys-Asp-Gly-Tyr-Leu-Val-Asn-Lys-Tyr-Thr-Gly-Cys-Lys-Val-Asn-Cys- Tyr-Lys-Leu-Gly-Glu-Asn-Lys-Phe-Cys-Asn-Arg-Glu-. 3. A polypeptide toxic to mice (component II.6) from this venom was shown to have the following N-terminal sequence: Lys-Glu-Gly-Tyr-Leu-Val-Asn-His-Ser-Thr-Gly-Cys-Lys-Tyr- Glu-Cys-Tyr-Lys-Leu-Gly-Asp-Asn-Asp-Tyr-Cys-Leu-Arg-Glu-Cys-Lys-. 4. In cultured chick dorsal root ganglion cells, 1 microM of toxin II.6 was shown to reduce the size of sodium currents and to slow-down their activation-inactivation kinetics. The toxin had also a depressive action on the classical Ca2+ current activated at high membrane potentials (greater than 0 mV).


Assuntos
Venenos de Escorpião/isolamento & purificação , Sequência de Aminoácidos , Animais , Galinhas , Estimulação Elétrica , Eletrofisiologia , Canais Iônicos/efeitos dos fármacos , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Venenos de Escorpião/toxicidade , Escorpiões , Solubilidade
5.
Biochemistry ; 25(10): 2927-33, 1986 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-3087412

RESUMO

A phospholipase A2 was isolated from the venom of the mexican beaded lizard (Heloderma horridum horridum) by phenyl-Sepharose chromatography followed by Sephadex G-75 gel filtration and two additional steps on ion exchange resins (DE-32 cellulose). The affinity chromatographic method (PC-Sepharose 4B) reported for the isolation of other phospholipases [Rock, Ch. O., & Snyder, F. (1975) J. Biol. Chem. 250, 2564-2566; King, T. P., Alagon, A. C., Kwan, J., Sobotka, A. K., & Lichteinstein, L. M. (1983) Mol. Immunol. 20, 297-308; King, T. P., Kochoumian, L., & Joslyn, A. (1984) Arch. Biochem. Biophys. 230, 1-12] was uneffective for the separation of this enzyme. The monomeric form of the Heloderma phospholipase has an apparent Mr of 18 000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 19 060 as calculated from amino acid analysis. It also contains on the order of 7% carbohydrates per mole of enzyme. The N-terminal amino acid sequence was shown to be very different from that of phospholipases isolated from mammalian pancreas and crotalids and elapids snake venoms. The first 39 amino acid residues at the N-terminal region have 56% homology with bee venom phospholipase but differ from the bee phospholipase in that its isoelectric point is acidic (pI = 4.5), instead of basic, and it has approximately 50 amino acid residues more in the molecule. The specificity of the enzyme is mainly A2 type with possible residual B-type activity. The enzymatic activity is Ca2+-dependent. Half-cystine alignment of the Heloderma phospholipase sequence with those of other known phospholipases shows the lack of an octadecapeptide at the N-terminal region, the existence of an extra hexapeptide at positions 42-47, and an exact correspondence of Heloderma Gly-12, Gly-14, His-36, and Asp-37 with Gly-30, Gly-32, His-48, and Asp-49 from other phospholipases shown to be important for Ca2+ binding (( Dijkstra, B. W., Drenth, J., Kalk, K. H., & Vandermaalen, P. J. (1978) J. Mol. Biol. 124, 53-60 )).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fosfolipases A/isolamento & purificação , Fosfolipases/isolamento & purificação , Peçonhas/isolamento & purificação , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Carboidratos/análise , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Imunodifusão , Imunoeletroforese , Lagartos , Fosfolipases A/metabolismo , Fosfolipases A2 , Especificidade da Espécie
6.
Mol Immunol ; 20(3): 297-308, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6865952

RESUMO

The major proteins of yellowjacket venoms have been isolated and characterized immuno-chemically. They consist of hyaluronidase, phospholipase, and antigen 5. Venoms from three species of yellowjacket were studied. Vespula germanica, V. maculifrons, and V. vulgaris. The phospholipases could be isolated in good yield only when affinity chromatography was used to minimize limited proteolysis. A kallikrein-like peptidase was found present in the yellowjacket venom. Phospholipases from these three species were immunochemically indistinguishable from each other, as were their antigen 5s. Sera from individuals sensitive to yellowjacket venom contained IgE and IgG specific for antigen 5 and phospholipase.


Assuntos
Venenos de Abelha/imunologia , Proteínas/imunologia , Venenos de Vespas/imunologia , Aminoácidos/análise , Animais , Antígenos/imunologia , Antígenos/isolamento & purificação , Cromatografia de Afinidade , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Humanos , Hialuronoglucosaminidase/imunologia , Hialuronoglucosaminidase/isolamento & purificação , Imunoglobulina E/análise , Imunoglobulina G/análise , Imunoglobulina G/biossíntese , Camundongos , Fosfolipases/imunologia , Fosfolipases/isolamento & purificação , Proteínas/isolamento & purificação
7.
Toxicon ; 20(2): 463-75, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7080053

RESUMO

The venom from the lizards Heloderma horridum horridum and Heloderma horridum alvarezi was obtained at a protein concentration of 80 mg/ml with a pH value of 6.9-7.0. The volume of venom obtained is approximately 0.5 ml per extraction. The i.p. LD50 value in mice for both sub-species is 2 mg/kg body weight. The electrophoretic pattern of the venom applied to polyacrylamide gels shows at least 18 protein bands and this pattern is constant for the same animal during all 12 months of the year, although different animals from the same population may present a slightly different pattern. The venom has the following enzymatic activities: phospholipase A, hyaluronidase, and Bz-Arg-OEt and Bz-Tyr-OEt hydrolase. Some of the venom components can be selectively and reversibly precipitated at acidic pH (4.7). The venom is very immunogenic and the sheep anti-sera against both sub-species cross-react quite extensively. A Bz-Arg-OEt hydrolase was purified from the venom of H. h. horridum by column chromatography in Sephadex G-75 followed by two steps on DEAE-cellulose columns at two different pH values (7.55 and 8.6). The last step was chromatography in a phenyl-sepharose column. The molecular weight of this enzyme, as obtained by SDS-gel electrophoresis, is approx. 65,000.


Assuntos
Hidrolases de Éster Carboxílico/isolamento & purificação , Lagartos , Peçonhas/isolamento & purificação , Animais , Eletroforese em Gel de Poliacrilamida , Dose Letal Mediana , Lagartos/metabolismo , Camundongos , Peso Molecular , Peçonhas/imunologia , Peçonhas/toxicidade
8.
Biochim Biophys Acta ; 669(2): 183-92, 1981 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-7284435

RESUMO

This paper reports on spectroscopic studies of six toxins from the Latin American scorpions Centruroides noxius Hoffmann, Centruroides elegans Thorell and Tityus serrulatus Lutz and Mello. The isolation and purification of five of these toxins was described previously. The preparation of toxin II.9.2.2 from the venom of C. noxius is first described here. Circular dichroism and nuclear magnetic resonance spectra indicate similarities and differences between these scorpion toxins and previously characterized snake toxins. While there is evidence that the toxins from scorpions and snakes both contain extended beta-sheet secondary structures, the spectral properties of the scorpion toxins are overall of a different type from those of snake toxins. Among the six scorpion toxins those from T. serrulatus have spectral properties markedly different from those of the Centruroides species. Furthermore, thermal denaturation and amide proton exchange measurements showed that the globular structures of the Tityus toxins were markedly less stable and less rigid than those of the Centruroides toxins.


Assuntos
Venenos de Escorpião/isolamento & purificação , Aminoácidos/análise , Animais , Cromatografia em Gel , Cromatografia por Troca Iônica , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Proteica , Venenos de Escorpião/toxicidade , Especificidade da Espécie
9.
Biochemistry ; 19(18): 4341-5, 1980 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-7417409

RESUMO

2-Iminothiolane, a cyclic thioimidate, is known to react readily with amino groups of proteins to give amidinated derivatives containing reactive sulfhydryl groups. In this report it will be shown that 2-iminothiolane also reacts with hydroxyl and sulfhydryl groups. Such a reaction with hydroxyl groups can be used to introduce sulfhydryl groups into polysaccharides. When this reaction is carried out in the presence of 4,4'-dithiodipyridine, polysaccharides containing 4-dithiopyridyl groups can be prepared. These activated polysaccharides couple easily via intermolecular disulfide bond formation with proteins containing thiol or 4-dithiopyridyl groups. The resulting polysaccharide--protein conjugates have good stability, and they are useful reagents for different biochemical applications such as the purification of proteins containing thiol groups and affinity chromatography.


Assuntos
Alérgenos , Imidoésteres , Proteínas de Plantas , Pólen , Polissacarídeos , Antígenos de Plantas , Fenômenos Químicos , Química , Cromatografia de Afinidade , Soros Imunes , Cinética , Proteínas/isolamento & purificação , Sefarose/análogos & derivados , Compostos de Sulfidrila
10.
Biochem J ; 185(3): 695-704, 1980 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7387631

RESUMO

The water-soluble venom of Bothrops asper Garman (San Juan Evangelista, Veracruz, México) showed 15 polypeptide bands on polyacrylamide-gel electrophoresis. This material exhibited phospholipase, hyaluronidase, N-benzoyl-l-arginine ethyl hydrolase, N-benzoyl-l-tyrosine ethyl hydrolase and phosphodiesterase activity, but no alkaline phosphatase or acid phosphatase activity. Fractionation on Sephadex G-75 afforded seven protein fractions, which were apparently less toxic than the whole venom (LD(50)=4.3mug/g mouse wt.). Subsequent separation of the phospholipase-positive fraction (II) on DEAE-cellulose with potassium phosphate buffers (pH7.55) gave several fractions, two being phospholipase-positive (II.6 and II.8). These fractions were further purified on DEAE-cellulose columns with potassium phosphate buffers (pH8.6). Fraction II.8.4 was rechromatographed in the same DEAE-cellulose column, giving a pure protein designated phospholipase 1. The fraction II.6.3 was further separated by gel disc electrophoresis yielding two more pure proteins designated phospholipase 2 and phospholipase 3. Analysis of phospholipids hydrolysed by these enzymes have shown that all three phospholipases belong to type A(2). Amino acid analysis has shown that phospholipase A(2) (type 1) has 97 residues with a calculated mol.wt. of 10978+/-11. Phospholipase A(2) (type 2) has 96 residues with a mol.wt. of 10959+/-11. Phospholipase A(2) (type 3) has 266 residues with 16 half-cystine residues and a calculated mol.wt of 29042+/-31. Automated Edman degradation showed the N-terminal sequence to be: Asx-Leu-Trp-Glx-Phe-Gly-Glx-Met-Met-Ser-Asx-Val- Met-Arg-Lys-Asx-Val-Val-Phe-Lys-Tyr-Leu- for phospholipase A(2) (type 2).


Assuntos
Venenos de Crotalídeos , Fosfolipases A/isolamento & purificação , Fosfolipases/isolamento & purificação , Aminoácidos/análise , Cromatografia DEAE-Celulose , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Ácidos Graxos/análise
13.
Biochem J ; 179(3): 603-6, 1979 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-475771

RESUMO

A phospholipase A2 was purified from the Mexican coral snake Micrurus fulvius microgalbieus (Brown and Smith). Gel filtration of the soluble crude venom on Sephadex g-50 resolved five fractions, of which fraction II had 98% of the total phospholipase activity. This fraction was rechromatographed on a CM-cellulose column that resolved eight fractions, four of which had an important phospholipase activity. The first fraction (II-1) was homogeneous by polyacrylamide-gel electrophoresis and displayed a phospholipase specific activity of 920 units/mg of protein. The apparent molecular weight as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was approx. 14000. The amino acid analysis revealed the presence of 119 amino acid residues, with 12 half-cystines. the N-terminal sequence was shown to be Ser-Leu-Leu-Asx-Phe-Lys-Asx-Met-Ile-Glu-Ser-Thr..., which is homologous with that of phospholipases from other snake venoms.


Assuntos
Venenos Elapídicos/análise , Fosfolipases/isolamento & purificação , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Cromatografia em Gel , Cromatografia por Troca Iônica , Camundongos , Peso Molecular
14.
Comp Biochem Physiol B ; 64(2): 231-4, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-318305

RESUMO

1. The venoms of 22 species of arthropods, saurians, elapids and crotalids were studied concerning the phospholipase activity and the presence of a direct and an indirect lytic effect upon human red cells. 2. The venoms from the spiders Latrodectus and "tarantula", and the venoms from the scorpions of the genus Centruroides are not haemolytic and do not have phospholipase activity. 3. Only the venoms of Apis mellifera and Naja naja siamensis have shown direct lytic effect. 4. All other venoms studied have an indirect haemolytic effect associated to a phospholipase activity, but there is indication that other agents might be implicated in the haemolytic processes.


Assuntos
Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Fosfolipases/análise , Peçonhas/toxicidade , Animais , Artrópodes , Humanos , Técnicas In Vitro , Venenos de Serpentes/farmacologia , Venenos de Serpentes/toxicidade , Solventes , Especificidade da Espécie , Peçonhas/farmacologia
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