Isolation and characterisation of transposon-induced mutants of Erwinia carotovora subsp. atroseptica exhibiting reduced virulence

@article{Hinton2004IsolationAC,
  title={Isolation and characterisation of transposon-induced mutants of Erwinia carotovora subsp. atroseptica exhibiting reduced virulence},
  author={Jay C. D. Hinton and Julie M. Sidebotham and L. J. Hyman and Michel C. M. P{\'e}rombelon and George P. C. Salmond},
  journal={Molecular and General Genetics MGG},
  year={2004},
  volume={217},
  pages={141-148}
}
SummaryThe blackleg pathogen Erwinia carotovora subsp. atroseptica (Eca) causes an economically important disease of potatoes. We selected a genetically amenable Eca strain for the genetic analysis of virulence. Tn5 mutagenesis was used to generate nine mutants which exhibited reduced virulence (Rvi-) of strain SCRI1043. Following physiological characterisation, mutants were divided into three classes: (1) auxotrophs; (2) extracellular enzyme mutants; and (3) a growth rate mutant. The isolation… 
Two mobile Pectobacterium atrosepticum prophages modulate virulence.
TLDR
Deletion of the entire prophages, both separately and in combination, did not affect the growth rate or the secretion of plant cell wall-degrading enzymes, but swimming motility was decreased and the virulence of prophage deletion strains in the potato host was decreased.
Exploitation of a new flagellatropic phage of Erwinia for positive selection of bacterial mutants attenuated in plant virulence: towards phage therapy
Aims:  To isolate and characterize novel bacteriophages for the phytopathogen, Erwinia carotovora ssp. atroseptica (Eca), and to isolate phage‐resistant mutants attenuated in virulence.
Bacterial diseases of potatoes: from classical phytobacteriology to molecular pathogenicity
  • G. Salmond
  • Biology
    Netherlands Journal of Plant Pathology
  • 2005
TLDR
Advances in the molecular biological analysis of several bacterial pathogens are helping to understand the major aspects of virulence mechanisms, but to date such information is not sufficiently useful to allow us to intervene rationally in these potato diseases, except by the standard practises of good husbandry.
Genome wide identification of genes required for bacterial plant infection by Tn-seq
TLDR
Tn-seq is used for the first time in a plant pathogenic bacteria to identify genes required for the multiplication of Dickeya dadantii in chicory and it is shown that D.Dadantii flagellin is glycosylated and that this modification confers fitness to the bacteria during plant infection.
Expression of pehA-bla gene fusions in Erwinia carotovora subsp. carotovora and isolation of regulatory mutants affecting polygalacturonase production
TLDR
The PehR−1 as well as PehA−1 mutants exhibited a reduced virulence phenotype suggesting that polygalacturonase is a virulence factor in Ecc, and two classes of regulatory mutants were obtained by this selection.
Identification of the central quorum sensing regulator of virulence in the enteric phytopathogen, Erwinia carotovora: the VirR repressor
TLDR
It is demonstrated that the VirR regulatory pathway is present and functional in both blackleg and soft rotting species of Erwinia, and evidence that VirR acts to prevent the production of virulence factors at low cell density is provided.
Identification by Tn‐seq of Dickeya dadantii genes required for survival in chicory plants
TLDR
This study demonstrated that the biosynthetic pathways of leucine, cysteine and lysine were essential for bacterial survival in the plant and that RsmC and GCPA were important in the regulation of the infection process, as the mutants ∆rsmC and ∆gcpA were hypervirulent.
RelA-Dependent (p)ppGpp Production Controls Exoenzyme Synthesis in Erwinia carotovora subsp. atroseptica
TLDR
It is concluded that nutrient limitation is a potent environmental cue that triggers (p)ppGpp-dependent exoenzyme production in E. carotovora subsp.
Use of a pooled transposon mutation grid to demonstrate roles in disease development for Erwinia carotovora subsp. atroseptica putative type III secreted effector (DspE/A) and helper (HrpN) proteins.
TLDR
An arrayed set of Tn5 insertional mutants was constructed and pooled to allow rapid isolation of mutants for any given gene by polymerase chain reaction screening, and this novel approach was used to obtain mutations in two structural genes (hrcC and hrcV) and the effector gene dspE/A, and the helper gene hrpN.
A metabolic regulator modulates virulence and quorum sensing signal production in Pectobacterium atrosepticum.
TLDR
The metJ mutant strains showed pleiotropic transcriptional impacts affecting approximately a quarter of the genome and genes involved in methionine biosynthesis were most highly upregulated but many virulence-associated transcripts were also upregulated.
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TLDR
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TLDR
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