In:
Environmental Microbiology, Wiley, Vol. 17, No. 11 ( 2015-11), p. 4189-4199
Kurzfassung:
Oyster diseases caused by pathogenic vibrios pose a major challenge to the sustainability of oyster farming. In F rance, since 2012 a disease affecting specifically adult oysters has been associated with the presence of V ibrio aestuarianus. Here, by combining genome comparison, phylogenetic analyses and high‐throughput infections of strains isolated before or during the recent outbreaks, we show that virulent strains cluster into two V . aestuarianus lineages independently of the sampling dates. The bacterial lethal dose was not different between strains isolated before or after 2012. Hence, the emergence of a new highly virulent clonal strain is unlikely. Each lineage comprises nearly identical strains, the majority of them being virulent, suggesting that within these phylogenetically coherent virulent lineages a few strains have lost their pathogenicity. Comparative genomics allowed the identification of a single frameshift in a non‐virulent strain. This mutation affects the varS gene that codes for a signal transduction histidine‐protein kinase. Genetic analyses confirmed that varS is necessary for infection of oysters and for a secreted metalloprotease expression. For the first time in a V ibrio species, we show here that VarS is a key factor of pathogenicity.
Materialart:
Online-Ressource
ISSN:
1462-2912
,
1462-2920
DOI:
10.1111/emi.2015.17.issue-11
DOI:
10.1111/1462-2920.12699
Sprache:
Englisch
Verlag:
Wiley
Publikationsdatum:
2015
ZDB Id:
2020213-1
SSG:
12