Data/hora: 07/06/2024 07:25:12

Provedor de dados: 	5	
País: 	France	
Título: 	Proteinaceous exotoxins of shrimp-pathogenic isolates of Vibrio penaeicida and Vibrio nigripulchritudo	
Autores: 	Aguirre-guzman, Gabriel; Labreuche, Yannick; Ansquer, Dominique; Espiau, Benoit; Levy, Peva; Ascencio, Felipe; Saulnier, Denis.	
Data: 	2003	
Ano: 	2003	
Palavras-chave: 	Pathogenicity; Exotoxin; Shrimp; Litopenaeus stylirostris; Vibrio nigripulchritudo; Vibrio penaeicida.	
Resumo: 	The pathogenicity of two V. penaeicida strains, AM101 and KH-1, with different geographic origin, and V. nigripulchritudo strain AM102, were investigated in juvenile blue shrimp species Litopenaeus stylirostris. Alive bacteria and protein fractions (PFs) obtained from cell-free supernatants (CFS) were used in experimental challenges. Strains AM102, AM101, and KH-1 produced respectively 60, 54 and 12% mortality at 96h after infection using 104 cfu mL-1 of bacterial suspension. Exocellular toxin-like factors were evidenced in CFS from the New Caledonian strains (AM102 and AM101) but not the Japanese strain (KH-1). At 48h post injection of each CFS, mortality rates were respectively 96,98 and 5% when these strains were cultivated at 20°C, whereas only O,16 and 5% mortality rates were observed when these strains were cultivated at 30°C. Clear differences in pathogenicity between both V. penaeicida strains of distinct geographic origin (AM101 and KH-1) were thus emphasized. Protein fractions were obtained from CFS of all the strains tested in this study and cultivated at 20°C, by ammonium sulphate precipitation. Whatever the used strain, significantly higher mortalities were produced with PFs obtained with 0-40% of ammonium sulphate saturation, in respect to those produced with PFs60 and PFs80. Shrimp injected with PFs40 from strains AM102, AM101 and KH-1, and at a 20-µg org-1 dose produced respectively 100, 90 and 60% mortality 46h after the challenge. The strain AM101 showed a mediam lethal dose of approximately 5µg protein org-1 (1-1.25 µg protein g-1 body weight) 59h after injection. The PFs40 from New Caledonian strains were fond sensitive to heating and proteinase K treatments, reinforcing thus the hypothesis of their proteinaceous nature. Surprisingly, PFs40 from each bacterial strain displayed similar protein bands by SDS-PAGE suggesting that the tested strains share a common exotoxic compound regardless their distinct geographic origin or species.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/2003/publication-2807.pdf	
Editor: 	Universidad Autonoma de Baja California	
Relação: 	http://archimer.ifremer.fr/doc/00000/2807/	
Formato: 	application/pdf	
Fonte: 	Ciencias Marinas (Universidad Autonoma de Baja California), 2003 , Vol. 29 , N. 1 , P. 77-88	
Fonte: 	Universidad Autonoma de Baja California