| Registro completo |
| Provedor de dados: |
J. Venom. Anim. Toxins incl. Trop. Dis.
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| País: |
Brazil
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| Título: |
Purification and n-terminal sequencing of two presynaptic neurotoxic PLA2, neuwieditoxin-I and neuwieditoxin-II, from Bothrops neuwiedi pauloensis (jararaca pintada) venom
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| Autores: |
Borja-Oliveira,C. R.
Kassab,B. H.
Soares,A. M.
Toyama,M. H.
Giglio,J. R.
Marangoni,S.
Re,L.
Rodrigues-Simioni,L.
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| Data: |
2007-01-01
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| Ano: |
2007
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| Palavras-chave: |
Chick biventer cervicis
Loose patch clamp
Nerve-muscle preparation
Neuromuscular junction
Neurotoxicity
PLA2 neurotoxin
Presynaptic action
Bothrops neuwiedi pauloensis
Neuwieditoxin-I
Neuwieditoxin-II
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| Resumo: |
Two presynaptic phospholipases A2 (PLA2), neuwieditoxin-I (NeuTX-I) and neuwieditoxin-II (NeuTX-II), were isolated from the venom of Bothrops neuwiedi pauloensis (BNP). The venom was fractionated using molecular exclusion HPLC (Protein-Pak 300SW column), followed by reverse phase HPLC (µBondapak C18 column). Tricine-SDS-PAGE in the presence or absence of dithiothreitol showed that NeuTX-I and NeuTX-II had a molecular mass of approximately 14 kDa and 28kDa, respectively. At 10µg/ml, both toxins produced complete neuromuscular blockade in indirectly stimulated chick biventer cervicis isolated preparation without inhibiting the response to acetylcholine, but NeuTX-II reduced the response to KCl by 67.0±8.0% (n=3; p<0.05). NeuTX-I and NeuTX-II are probably responsible for the presynaptic neurotoxicity of BNP venom in vitro. In fact, using loose patch clamp technique for mouse phrenic nerve-diaphragm preparation, NeuTX-I produced a calcium-dependent blockade of acetylcholine release and caused appearance of giant miniature end-plate potentials (mepps), indicating a pure presynaptic action. The N-terminal sequence of NeuTX-I was DLVQFGQMILKVAGRSLPKSYGAYGCYCGWGGRGK (71% homology with bothropstoxin-II and 54% homology with caudoxin) and that of NeuTX-II was SLFEFAKMILEETKRLPFPYYGAYGCYCGWGGQGQPKDAT (92% homology with Basp-III and 62% homology with crotoxin PLA2). The fact that NeuTX-I has Q-4 (Gln-4) and both toxins have F-5 (Phe-5) and Y-28 (Tyr-28) strongly suggests that NeuTX-I and NeuTX-II are Asp49 PLA2.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992007000100008
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| Editor: |
Centro de Estudos de Venenos e Animais Peçonhentos
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| Relação: |
10.1590/S1678-91992007000100008
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| Formato: |
text/html
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| Fonte: |
Journal of Venomous Animals and Toxins including Tropical Diseases v.13 n.1 2007
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| Direitos: |
info:eu-repo/semantics/openAccess
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