Data/hora: 04/06/2024 02:19:43

Provedor de dados: 	Institutional Archive of Ifreme (ArchiMer)	
País: 	France	
Título: 	Identification de marqueurs génétiques de la virulence chez Vibrio nigripulchritudo, un pathogène de crevettes pénéides en Nouvelle-Calédonie	
Autores: 	Reynaud, Yann.	
Data: 	2008-04-08	
Ano: 	2008	
Palavras-chave: 	Plasmide; SSH; Épidémiology; Virulence; Shrimp; Vibriosis; Vibrio nigripulchritudo; Plasmide; SSH; Épidémiologie; Virulence; Crevette; Vibriose; Vibrio nigripulchritudo.	
Resumo: 	Since 1997, a new pathology seasonally occurs in new caledonian shrimp farms during the warm season and was named Summer Syndrome. Diseased Litopenaeus stylirostris shrimp suffer from a septicemic vibriosis which was attributed to V. nigripulchritudo. Preliminary studies based on a collection of V. nigripulchritudo strains have brought to light different virulence levels according to experimental infections results; three virulence statuses were defined: highly (HP), moderately (MP) and non pathogenic (NP). The aim of this work was to genetically characterize virulent V. nigripulchritudo strains. In a first step the genetic diversity of 58 V. nigripulchritudo strains was analyzed by MLST and AP-PCR, revealing a cluster of HP and MP strains, characterized by a low genetic variability and that includes all Summer Syndrome-associated isolates. This confirms the emergence of one cluster of pathogenic V. nigripulchritudo simultaneously with the emergence of the Summer Syndrome ; in a second step, 368 genetic markers of virulence were identified by a Suppressive Subtractive Hybridization performed between the genomes of a HP strain and a genetically close, NP isolate; the distribution of the screened SSH fragments was studied in 58 V. nigripulchritudo isolates by macro-array: 78 DNA fragments were selected, allowing to characterize clusters identified and pathogenic statuses; 13 are specific of the HP strains involved in Summer Syndrome. Interestingly, 10 of these markers are carried by a plasmid pSFn1 that contains sequences highly similar to those of a plasmid pAK1, detected in Vibrio shilonii, a coral pathogen. The origin and consequences of this plasmid acquisition are discussed.	
Tipo: 	Text	
Idioma: 	Francês	
Identificador: 	http://archimer.ifremer.fr/doc/2008/these-3906.pdf	
Editor: 	Université de Paris 6 – Pierre et Marie Curie	
Relação: 	http://archimer.ifremer.fr/doc/00000/3906/	
Formato: 	application/pdf