20+ Million Readerbase
Indexed In
  • Open J Gate
  • Genamics JournalSeek
  • Academic Keys
  • JournalTOCs
  • CiteFactor
  • Ulrich's Periodicals Directory
  • Access to Global Online Research in Agriculture (AGORA)
  • Electronic Journals Library
  • Centre for Agriculture and Biosciences International (CABI)
  • RefSeek
  • Directory of Research Journal Indexing (DRJI)
  • Hamdard University
  • EBSCO A-Z
  • OCLC- WorldCat
  • Scholarsteer
  • SWB online catalog
  • Virtual Library of Biology (vifabio)
  • Publons
  • Geneva Foundation for Medical Education and Research
  • Euro Pub
  • Google Scholar
Share This Page
Journal Flyer
Flyer image

Abstract

Characterization of Xylella fastidiosa popP Gene Required for Pathogenicity

Xiangyang Shi and Hong Lin

Xylella fastidiosa (Xf) possess a two component regulatory system (TCS) PopP-PopQ which differentially regulates genes in response to environmental stimuli. To elucidate the role of popP in the pathogenicity of X. fastidiosa causing Pierce’s disease (PD) of grapevine, a site-directed deletion method and chromosome-based genetic complementation strategy were employed to create popP deletion mutant XfΔpopP and its complementary strain XfΔpopP-C. In vitro studies showed that while all strains had similar growth curves, XfΔpopP showed significant reduction in cell-cell aggregation and cell-matrix adherence. Biofilm production of XfΔpopP was about 42% less than that of wild type X. fastidiosa and XfΔpopP-C. No symptoms were observed in grapevines inoculated with XfΔpopP, whereas grapevines inoculated with wild type X. fastidiosa and XfΔpopP-C showed typical PD symptoms. Several biofilm-related genes and genes involving protein secretary systems were down regulated in XfΔpopP in compared with wild type X. fastidiosa and XfΔpopP-C. These in vitro and in planta assay results provide strong evidence that the role of PopP is required for pathogenicity of X. fastidiosa on grapevine.