The genome sequence of the plant pathogen Xylella fastidiosa. The Xylella fastidiosa Consortium of the Organization for Nucleotide Sequencing and Analysis

Nature. 2000 Jul 13;406(6792):151-9. doi: 10.1038/35018003.


Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Adhesion
  • Bacterial Proteins / metabolism
  • Biological Transport
  • Chromosome Mapping
  • Citrus / microbiology
  • DNA Repair
  • DNA, Bacterial
  • Energy Metabolism
  • Genome, Bacterial*
  • Molecular Sequence Data
  • Nicotiana / microbiology
  • Plants / microbiology*
  • Plants, Toxic
  • Protein Biosynthesis
  • Pseudomonadaceae / genetics*
  • Pseudomonadaceae / metabolism
  • Pseudomonadaceae / pathogenicity
  • Sequence Analysis, DNA*
  • Transcription, Genetic
  • Virulence / genetics


  • Bacterial Proteins
  • DNA, Bacterial

Associated data

  • GENBANK/AE003849
  • GENBANK/AE003850
  • GENBANK/AE003851