Phylogenetic analysis of a gene cluster encoding an additional, rhizobial-like type III secretion system that is narrowly distributed among Pseudomonas syringae strains.
BMC Microbiol
; 12: 188, 2012 Sep 02.
Article
em En
| MEDLINE
| ID: mdl-22937899
ABSTRACT
BACKGROUND:
The central role of Type III secretion systems (T3SS) in bacteria-plant interactions is well established, yet unexpected findings are being uncovered through bacterial genome sequencing. Some Pseudomonas syringae strains possess an uncharacterized cluster of genes encoding putative components of a second T3SS (T3SS-2) in addition to the well characterized Hrc1 T3SS which is associated with disease lesions in host plants and with the triggering of hypersensitive response in non-host plants. The aim of this study is to perform an in silico analysis of T3SS-2, and to compare it with other known T3SSs.RESULTS:
Based on phylogenetic analysis and gene organization comparisons, the T3SS-2 cluster of the P. syringae pv. phaseolicola strain is grouped with a second T3SS found in the pNGR234b plasmid of Rhizobium sp. These additional T3SS gene clusters define a subgroup within the Rhizobium T3SS family. Although, T3SS-2 is not distributed as widely as the Hrc1 T3SS in P. syringae strains, it was found to be constitutively expressed in P. syringae pv phaseolicola through RT-PCR experiments.CONCLUSIONS:
The relatedness of the P. syringae T3SS-2 to a second T3SS from the pNGR234b plasmid of Rhizobium sp., member of subgroup II of the rhizobial T3SS family, indicates common ancestry and/or possible horizontal transfer events between these species. Functional analysis and genome sequencing of more rhizobia and P. syringae pathovars may shed light into why these bacteria maintain a second T3SS gene cluster in their genome.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Filogenia
/
Família Multigênica
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Pseudomonas syringae
/
Sistemas de Secreção Bacterianos
Idioma:
En
Revista:
BMC Microbiol
Assunto da revista:
MICROBIOLOGIA
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Grécia