Data/hora: 11/06/2024 03:45:53

Provedor de dados: 	80	
País: 	Brazil	
Título: 	Purification of an L-amino acid oxidase from Bungarus caeruleus (Indian krait) venom	
Autores: 	More,SS; Kiran,KM; Veena,SM; Gadag,JR.	
Data: 	2010-01-01	
Ano: 	2010	
Palavras-chave: 	L-amino acid oxidase; Bungarus caeruleus; Platelet aggregation.	
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.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992010000100007	
Editor: 	Centro de Estudos de Venenos e Animais Peçonhentos	
Relação: 	10.1590/S1678-91992010005000002	
Formato: 	text/html	
Fonte: 	Journal of Venomous Animals and Toxins including Tropical Diseases  v.16 n.1 2010	
Fonte: 	info:eu-repo/semantics/openAccess