Titre : | Analysis of plasmid diversity in 96 Rhodococcus equi strains isolated in Normandy (France) and sequencing of the 87-kb type I virulence plasmid (2010) |
Auteurs : | F. Duquesne ; L. Hebert ; C. Sevin ; M.F. Breuil ; Jackie Tapprest ; C. Laugier ; S. Petry |
Type de document : | Article : texte imprimé |
Dans : | FEMS MICROBIOLOGY LETTERS (n311, 2010-01-01) |
Article en page(s) : | p.76-81 |
Langues: | Anglais |
Mots-clés : |
Equivoc Autopsie ; Biologie ; Environnement ; Épidémiologie ; Normandie ; Rhodococcose |
Résumé : | To characterize the potential epidemiological relationship between the origin of Rhodococcus equi strains and the type of their virulence plasmids, we performed a comparative analysis of virulence plasmid types encountered in 96 R. equi strains isolated from (1) autopsid horses, (2) organic samples (horse faeces, manure and straw) and (3) environmental samples. Our results revealed no clear epidemiological link between virulence plasmid type and the origin of R. equi strains isolated from horse-related environments. To understand this result, we determined the nucleotide sequence of the second most frequently isolated virulence plasmid type : a 87-kb type I (pVAPA116) plasmid and compared it with the previously sequenced (and most commonly encountred) 87-kb type I (pVAPA1037) plasmid. Our results show that the divergence between these two plasmids is manly due to the presence of three allelic exchange loci, resulting in the delection of two genes and the insertion of three genes in pVAPA116 compared with pVAPA1037. In conclusion, it appears that the divergence between the two sequenced rhodococcal virulence plasmids is not associated with the vap pathogenicity island and may result from a evolutionary process driven by a mobility-related invertase/resolvase invA-like gene. |
Cote du document numérique : | 15958 |
Classement cheval : | F05/F15 |