@article{fdi:010084634,
  title = {{P}henotypic and molecular-phylogenetic analyses reveal distinct features of crown gall-associated {X}anthomonas strains},
  author = {{M}afakheri, {H}. and {T}aghavi, {S}. {M}. and {Z}arei, {S}. and {R}ahimi, {T}. and {H}asannezhad, {M}. {S}. and {P}ortier, {P}. and {F}ischer-{L}e {S}aux, {M}. and {D}imkic, {I}. and {K}oebnik, {R}alf and {K}uzmanovic, {N}. and {O}sdaghi, {E}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n summer 2019, widespread occurrence of crown gall disease caused by {A}grobacterium spp. was observed on commercially grown ornamental plants in southern {I}ran. {B}eside agrobacteria, pale yellow-pigmented {G}ram-negative strains resembling the members of {X}anthomonas were also associated with crown gall tissues on weeping fig ({F}icus benjamina) and {A}maranthus sp. plants. {T}he purpose of the present study was to characterize the crown gall-associated {X}anthomonas strains using plant inoculation assays, molecular-phylogenetic analyses, and comparative genomics approaches. {P}athogenicity tests showed that the {X}anthomonas strains did not induce disease symptoms on their host of isolation. {H}owever, the strains induced hypersensitive reaction on tobacco, geranium, melon, squash, and tomato leaves via leaf infiltration. {M}ultilocus sequence analysis suggested that the strains belong to {G}lade {IA} of {X}anthomonas, phylogenetically close to {X}anthomonas translucens, {X}. theicoia, and {X}. hyacinthi. {A}verage nucleotide identity and digital {DNA}-{DNA} hybridization values between the whole-genome sequences of the strains isolated in this study and reference {X}anthomonas strains are far below the accepted thresholds for the definition of prokaryotic species, signifying that these strains could be defined as two new species within {G}lade {IA} of {X}anthomonas. {C}omparative genomics showed that the strains isolated from crown gall tissues are genetically distinct from {X}. translucens, as almost all the type {III} secretion system genes and type {III} effectors are lacking in the former group. {T}he data obtained in this study provide novel insight into the breadth of genetic diversity of crown gall-associated bacteria and pave the way for research on gall-associated {X}anthomonas-plant interactions. {IMPORTANCE} {T}umorigenic agrobacteria-members of the bacterial family {R}hizobiaceae-cause crown gall and hairy root diseases on a broad range of plant species. {T}hese bacteria are responsible for economic losses in nurseries of important fruit trees and ornamental plants. {T}he microclimate of crown gall and their accompanying microorganisms has rarely been studied for the microbial diversity and population dynamics of gall-associated bacteria. {H}ere, we employed a series of biochemical tests, pathogenicity assays, and molecular-phylogenetic analyses, supplemented with comparative genomics, to elucidate the biological features, taxonomic position, and genomic repertories of five crown gallassociated {X}anthomonas strains isolated from weeping fig and {A}maranthus sp. plants in {I}ran. {T}he strains investigated in this study induced hypersensitive reactions ({HR}) on geranium, melon, squash, tobacco, and tomato leaves, while they were nonpathogenic on their host of isolation. {P}hylogenetic analyses and whole-genome-sequence-based average nucleotide identity ({ANI})/digital {DNA}-{DNA} hybridization (d{DDH}) calculations suggested that the {X}anthomonas strains isolated from crown gall tissues belong to two taxonomically unique clades closely related to the {G}lade {IA} species of the genus, i.e, {X}. translucens, {X} hyacinthi, and {X}. theicola.},
  keywords = {{A}grobacterium sp. ; {A}maranthus sp. ; clade {I} {X}anthomonas ; {F}icus benjamina ; {T}3{SS} ; weeping fig},
  booktitle = {},
  journal = {{M}icrobiology {S}pectrum},
  volume = {10},
  numero = {1},
  pages = {e00577--21 [18 p.]},
  ISSN = {2165-0497},
  year = {2022},
  DOI = {10.1128/spectrum.00577-21},
  URL = {https://www.documentation.ird.fr/hor/fdi:010084634},
}