Functional Tn5393-like transposon in the R plasmid pRAS2 from the fish pathogen Aeromonas salmonicida subspecies salmonicida isolated in Norway.
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ABSTRACT:
SUBMITTER: L'Abee-Lund TM
PROVIDER: S-EPMC92499 | biostudies-literature | 2000 Dec
REPOSITORIES: biostudies-literature
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Functional Tn5393-like transposon in the R plasmid pRAS2 from the fish pathogen Aeromonas salmonicida subspecies salmonicida isolated in Norway.
Applied and environmental microbiology 20001201 12
Tn5393c containing strA-strB was identified as part of R plasmid pRAS2 from the fish pathogen Aeromonas salmonicida subsp. salmonicida. This is the first time an intact and active transposon in the Tn5393 family has been reported in an ecological niche other than an agricultural habitat. ...[more]
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Project description:A recently described typing system based on sequence variation in the virulence array protein (vapA) gene, encoding the A-layer surface protein array, allows unambiguous subtyping of Aeromonas salmonicida. In the present study, we compile A-layer typing results from a total of 675 A. salmonicida isolates, recovered over a 59-year period from 50 different fish species in 26 countries. Nine novel A-layer types (15-23) are identified, several of which display a strong predilection towards certain fish hosts, including e.g. Cyprinidae and Pleuronectidae species. Moreover, we find indications that anthropogenic transport of live fish may have aided the near global dissemination of two cyprinid-associated A-layer types. Comparison of whole genome phylogeny and A-layer typing for a subset of strains further resulted in compatible tree topologies, indicating the utility of vapA as a phylogenetic as well as an epizootiological marker in A. salmonicida. A Microreact project (microreact.org/project/r1pcOAx9m) has been created, allowing public access to the vapA analyses and relevant metadata. In sum, the results generated provide valuable insights into the global population structure of A. salmonicida, particularly in relation to its piscine host spectrum and the geographic distribution of these hosts.
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