Open AccessIdentification of a response regulator involved in surface attachment, cell–cell aggregation, exopolysaccharide production and virulence in the plant pathogen X ylella fastidiosa
Author(s) -
Voegel Tanja M.,
Doddapaneni Harshavardhan,
Cheng Davis W.,
Lin Hong,
Stenger Drake C.,
Kirkpatrick Bruce C.,
Roper M. Caroline
Publication year - 2013
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.12004
Subject(s) - xylella fastidiosa , biology , biofilm , mutant , virulence , histidine kinase , response regulator , gene , two component regulatory system , transcriptional regulation , pathogen , microbiology and biotechnology , genetics , gene expression , bacteria
Summary X ylella fastidiosa , the causal agent of P ierce's disease of grapevine, possesses several two‐component signal transduction systems that allow the bacterium to sense and respond to changes in its environment. Signals are perceived by sensor kinases that autophosphorylate and transfer the phosphate to response regulators ( RRs ), which direct an output response, usually by acting as transcriptional regulators. In the X . fastidiosa genome, 19 RRs were found. A site‐directed knockout mutant in one unusual RR, designated XhpT , composed of a receiver domain and a histidine phosphotransferase output domain, was constructed. The resulting mutant strain was analysed for changes in phenotypic traits related to biofilm formation and gene expression using microarray analysis. We found that the xhpT mutant was altered in surface attachment, cell–cell aggregation, exopolysaccharide ( EPS ) production and virulence in grapevine. In addition, this mutant had an altered transcriptional profile when compared with wild‐type X . fastidiosa in genes for several biofilm‐related traits, such as EPS production and haemagglutinin adhesins.