Transcriptome of Dickeya dadantii Infecting Acyrthosiphon pisum Reveals a Strong Defense against Antimicrobial Peptides. - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue PLoS ONE Année : 2013

Transcriptome of Dickeya dadantii Infecting Acyrthosiphon pisum Reveals a Strong Defense against Antimicrobial Peptides.

Résumé

The plant pathogenic bacterium Dickeya dadantii has recently been shown to be able to kill the aphid Acyrthosiphon pisum. While the factors required to cause plant disease are now well characterized, those required for insect pathogeny remain mostly unknown. To identify these factors, we analyzed the transcriptome of the bacteria isolated from infected aphids. More than 150 genes were upregulated and 300 downregulated more than 5-fold at 3 days post infection. No homologue to known toxin genes could be identified in the upregulated genes. The upregulated genes reflect the response of the bacteria to the conditions encountered inside aphids. While only a few genes involved in the response to oxidative stress were induced, a strong defense against antimicrobial peptides (AMP) was induced. Expression of a great number of efflux proteins and transporters was increased. Besides the genes involved in LPS modification by addition of 4-aminoarabinose (the arnBCADTEF operon) and phosphoethanolamine (pmrC, eptB) usually induced in Gram negative bacteria in response to AMPs, dltBAC and pbpG genes, which confer Gram positive bacteria resistance to AMPs by adding alanine to teichoic acids, were also induced. Both types of modification confer D. dadantii resistance to the AMP polymyxin. A. pisum harbors symbiotic bacteria and it is thought that it has a very limited immune system to maintain these populations and do not synthesize AMPs. The arnB mutant was less pathogenic to A. pisum, which suggests that, in contrast to what has been supposed, aphids do synthesize AMP.
Fichier principal
Vignette du fichier
journal.pone.0054118.pdf (517.66 Ko) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-00781257 , version 1 (25-01-2013)

Identifiants

Citer

Denis Costechareyre, Jean-François Chich, Jean-Marc Strub, Yvan Rahbé, Guy Condemine. Transcriptome of Dickeya dadantii Infecting Acyrthosiphon pisum Reveals a Strong Defense against Antimicrobial Peptides.. PLoS ONE, 2013, 8 (1), pp.e54118. ⟨10.1371/journal.pone.0054118⟩. ⟨hal-00781257⟩
431 Consultations
186 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More