Open AccessSurface polysaccharides and quorum sensing are involved in the attachment and survival of X anthomonas albilineans on sugarcane leaves
Author(s) -
Mensi Imene,
Daugrois JeanHeinrich,
Pieretti Isabelle,
Gargani Daniel,
Fleites Laura A.,
Noell Julie,
Bonnot Francois,
Gabriel Dean W.,
Rott Philippe
Publication year - 2016
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1111/mpp.12276
Subject(s) - quorum sensing , biology , pathogen , mutant , biofilm , microbiology and biotechnology , phyllosphere , polysaccharide , bacteria , gene , biochemistry , genetics
Summary X anthomonas albilineans , the causal agent of sugarcane leaf scald, is a bacterial plant pathogen that is mainly spread by infected cuttings and contaminated harvesting tools. However, some strains of this pathogen are known to be spread by aerial means and are able to colonize the phyllosphere of sugarcane before entering the host plant and causing disease. The objective of this study was to identify the molecular factors involved in the survival or growth of X . albilineans on sugarcane leaves. We developed a bioassay to test for the attachment of X . albilineans on sugarcane leaves using tissue‐cultured plantlets grown in vitro . Six mutants of strain XaFL07 ‐1 affected in surface polysaccharide production completely lost their capacity to survive on the sugarcane leaf surface. These mutants produced more biofilm in vitro and accumulated more cellular poly‐β‐hydroxybutyrate than the wild‐type strain. A mutant affected in the production of small molecules (including potential biosurfactants) synthesized by non‐ribosomal peptide synthetases ( NRPSs ) attached to the sugarcane leaves as well as the wild‐type strain. Surprisingly, the attachment of bacteria on sugarcane leaves varied among mutants of the rpf gene cluster involved in bacterial quorum sensing. Therefore, quorum sensing may affect polysaccharide production, or both polysaccharides and quorum sensing may be involved in the survival or growth of X . albilineans on sugarcane leaves.