TY  - JOUR
AU  - Pédron, Jacques
AU  - Van Gijsegem, Frédérique
PY  - 2019
DA  - 2019/11/26
TI  - Diversity in the Bacterial Genus <i>Dickeya</i> Grouping Plant Pathogens and Waterways Isolates
JO  - OBM Genetics
SP  - 098
VL  - 03
IS  - 04
AB  - Background: The Dickeya genus comprises aggressive soft rot plant pathogens with wide geographic distribution and host ranges.  Ten Dickeya species have been characterised. Seven of them (D. chrysanthemi, D. dadantii, D. dianthicola, D. fangzhongdai, D. solani, D. paradisiaca, D. zeae) group causative agents of maceration-associated diseases that impact a wide variety of crops and ornamentals. As well as isolates from water sources. The three remaining species (D. aquatica, D. lacustris, D. undicola) have recently been isolated only from water sources, so far. Here, we analysed the Dickeya genetic diversity in relation to species affiliation and habitats. 
Methods: We compared the genomes of 59 Dickeya strains, isolated from various hosts and from different environments, to determine their relatedness both at the genetic level (ANI) and concerning their pan-genome content as well as the occurrence of orthologous or species/strain specific gene families by SiLix analysis.
Results: Our study revealed the large conservation of virulence-associated genes in most Dickeya species (including “water-specific” ones), identified the genome-specific traits of the various species and highlighted the intra-species diversities.  At the species level, a contrasting diversity is observed with some species grouping highly related strains while other are much more diverse or at the limit of subdivision in separate species. This is not related to diversity in habitat or geographical origin neither in the extent of the species accessory genome or the number of strain-specific genes.  
Conclusions: The Dickeya genus pangenome analysis did not highlight strain clustering following host/environment of isolation and the different Dickeya species present few specific characteristics and even less specific gene losses that are frequently found in specialized human pathogens, reflecting the broad host range of this genus. No “water-specific” genes were identified pointing to Dickeya spread via waterways and thus irrigation water as a potential threat for economically important crops
SN  - 2577-5790
UR  - https://doi.org/10.21926/obm.genet.1904098
DO  - 10.21926/obm.genet.1904098
ID  - Pédron2019
ER  -