| Registro completo |
| Provedor de dados: |
J. Venom. Anim. Toxins incl. Trop. Dis.
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| País: |
Brazil
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| Título: |
Purification of an L-amino acid oxidase from Bungarus caeruleus (Indian krait) venom
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| Autores: |
More,SS
Kiran,KM
Veena,SM
Gadag,JR
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| Data: |
2010-01-01
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| Ano: |
2010
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| Palavras-chave: |
L-amino acid oxidase
Bungarus caeruleus
Platelet aggregation
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| Resumo: |
Snake venoms are rich in enzymes such as phospholipase A2, proteolytic enzymes, hyaluronidases and phosphodiesterases, which are well characterized. However, L-amino acid oxidase (LAO EC.1.4.3.2) from snake venoms has not been extensively studied. A novel L-amino acid oxidase from Bungarus caeruleus venom was purified to homogeneity using a combination of ion-exchange by DEAE-cellulose chromatography and gel filtration on Sephadex® G-100 column. The purified monomer of LAO showed a molecular mass of 55 ±1 kDa estimated by SDS-PAGE. The specific activity of purified LAO was 6,230 ± 178 U/min/mg, versus 230 ± 3.0 U/min/mg for the whole desiccated venom, suggesting a 27-fold purification with a 25% yield. Optimal pH and temperature for maximum purified enzyme activity were 6.5 and 37ºC, respectively. Platelet aggregation studies show that purified LAO inhibited ADP-induced platelet aggregation dose-dependently at 0.01 to 0.1 µM with 50% inhibitory concentration (IC50) of 0.04 µM, whereas at a 0.08 µM concentration it did not induce appreciable aggregation on normal platelet-rich plasma (PRP). The purified protein catalyzed oxidative deamination of L-amino acids while the most specific substrate was L-leucine. The purified LAO oxidizes only L-forms, but not D-forms of amino acids, to produce H2O2. The enzyme is important for the purification and determination of certain amino acids and for the preparation of α-keto acids.
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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=S1678-91992010000100007
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| Editor: |
Centro de Estudos de Venenos e Animais Peçonhentos
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| Relação: |
10.1590/S1678-91992010005000002
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| Formato: |
text/html
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| Fonte: |
Journal of Venomous Animals and Toxins including Tropical Diseases v.16 n.1 2010
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| Direitos: |
info:eu-repo/semantics/openAccess
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