Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

DsbA plays a critical and multi-faceted role in the production of secreted virulence factors by Erwinia carotovora

ABSTRACT: Erwinia carotovora subsp. atroseptica (Eca) is an enterobacterial phytopathogen causing economically-significant soft rot disease. Pathogenesis is mediated by multiple secreted virulence factors, many of which are secreted by the Type II (Out) secretion system. DsbA catalyses the introduction of disulphide bonds into periplasmic and secreted proteins. In this study, the extracellular proteome (secretome) of wild type Eca SCRI1043 and dsbA and out mutants was analysed by spectral counting mass spectrometry. This revealed that dsbA inactivation had a huge impact on the secretome and identified diverse DsbA- and Out-dependent secreted proteins, representing known, predicted and novel candidate virulence factors. Further characterisation of the dsbA mutant showed that secreted enzyme activities, motility, production of the quorum sensing signal and virulence were absent or greatly reduced. The impact of DsbA on secreted virulence factor production was mediated at multiple levels, including impacting on the Out secretion system and the virulence gene regulatory network. Transcriptome analyses revealed that the abundance of a broad, but defined, set of transcripts, including many virulence factors, was altered in the dsbA mutant, identifying a new virulence regulon responsive to extracytoplasmic conditions. In conclusion, DsbA plays a crucial, multi-faceted role in the pathogenesis of Eca. Keywords: Mutant comparison RNA samples used for genome-wide transcriptional profiling using microarrays: RNA was hybridised to four Eca genomic arrays, with each array hybridising one wild type and one dsbA mutant sample (from four independent cultures of each strain) and incorporating a dye-swap (i.e. wild type labelled with Cy3 in 2/4 and with Cy5 in 2/4).

ORGANISM(S): Pectobacterium carotovorum

SUBMITTER: Pete Hedley

PROVIDER: E-GEOD-10647 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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DsbA plays a critical and multifaceted role in the production of secreted virulence factors by the phytopathogen Erwinia carotovora subsp. atroseptica.

Coulthurst Sarah J SJ Lilley Kathryn S KS Hedley Peter E PE Liu Hui H Toth Ian K IK Salmond George P C GP

The Journal of biological chemistry 20080618 35

Erwinia carotovora subsp. atroseptica is an enterobacterial phytopathogen causing economically significant soft rot disease. Pathogenesis is mediated by multiple secreted virulence factors, many of which are secreted by the type II (Out) secretion system. DsbA catalyzes the introduction of disulfide bonds into periplasmic and secreted proteins. In this study, the extracellular proteome (secretome) of wild type E. carotovora subsp. atroseptica SCRI1043, and dsbA and out mutants, was analyzed by s ...[more]

PMID: 18562317

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Dataset Information

DsbA plays a critical and multi-faceted role in the production of secreted virulence factors by Erwinia carotovora

Publications

DsbA plays a critical and multifaceted role in the production of secreted virulence factors by the phytopathogen Erwinia carotovora subsp. atroseptica.

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