title: Full Genome Sequence Analysis of Two Isolates Reveals a Novel Xanthomonas Species Close to the Sugarcane Pathogen Xanthomonas albilineans.
abstract: Xanthomonas albilineans is the bacterium responsible for leaf scald, a lethal disease of sugarcane. Within the Xanthomonas genus, X. albilineans exhibits distinctive genomic characteristics including the presence of significant genome erosion, a non-ribosomal peptide synthesis (NRPS) locus involved in albicidin biosynthesis, and a type 3 secretion system (T3SS) of the Salmonella pathogenicity island-1 (SPI-1) family. We sequenced two X. albilineans-like strains isolated from unusual environments, i.e., from dew droplets on sugarcane leaves and from the wild grass Paspalum dilatatum, and compared these genomes sequences with those of two strains of X. albilineans and three of Xanthomonas sacchari. Average nucleotide identity (ANI) and multi-locus sequence analysis (MLSA) showed that both X. albilineans-like strains belong to a new species close to X. albilineans that we have named "Xanthomonas pseudalbilineans". X. albilineans and "X. pseudalbilineans" share many genomic features including (i) the lack of genes encoding a hypersensitive response and pathogenicity type 3 secretion system (Hrp-T3SS), and (ii) genome erosion that probably occurred in a common progenitor of both species. Our comparative analyses also revealed specific genomic features that may help X. albilineans interact with sugarcane, e.g., a PglA endoglucanase, three TonB-dependent transporters and a glycogen metabolism gene cluster. Other specific genomic features found in the "X. pseudalbilineans" genome may contribute to its fitness and specific ecological niche.
authors.affiliation: CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France. isabelle.pieretti@cirad.fr.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Pieretti
authors.affiliation: CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France. stephane.cociancich@cirad.fr.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cociancich
authors.affiliation: INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France. pcrott@ufl.edu.|CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France. pcrott@ufl.edu.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Bolot
authors.affiliation: INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France. pcrott@ufl.edu.|CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France. pcrott@ufl.edu.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Carrère
authors.affiliation: CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France. alexandre.morisset@outlook.com.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Morisset
authors.affiliation: CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France. philippe.rott@cirad.fr.
authors.forename: Philippe
authors.initials: P
authors.lastname: Rott
authors.affiliation: CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France. monique.royer@cirad.fr.
authors.forename: Monique
authors.initials: M
authors.lastname: Royer
keywords: ANI; MLSA; Xanthomonas albilineans; novel “Xanthomonas pseudalbilineans” species