Pacbio sequencing of copper-tolerant Xanthomonas citri reveals presence of a chimeric plasmid structure and provides insights into reassortment and shuffling of transcription activator-like effectors among X. citri strains.

Background: Xanthomonas citri, a causal agent of citrus canker, has been a well-studied model system due to recent availability of whole genome sequences of multiple strains from different geographical regions. Major limitations in our understanding of the evolution of pathogenicity factors in X. citri strains sequenced by short-read sequencing methods have been tracking plasmid reshuffling among strains due to inability to accurately assign reads to plasmids, and analyzing repeat regions among strains.

Recent advances in the understanding of Xanthomonas citri ssp. citri pathogenesis and citrus canker disease management.

Taxonomic status: Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Xanthomonadales; Family Xanthomonadaceae; Genus Xanthomonas; Species Xanthomonas citri ssp. citri (Xcc). Host range: Compatible hosts vary in their susceptibility to citrus canker (CC), with grapefruit, lime and lemon being the most susceptible, sweet orange being moderately susceptible, and kumquat and calamondin being amongst the least susceptible.

Molecular characterization of XopAG effector AvrGf2 from Xanthomonas fuscans ssp. aurantifolii in grapefruit.

Xanthomonas fuscans ssp. aurantifolii group C strains exhibit host specificity on different citrus species. The strains possess a type III effector, AvrGf2, belonging to the XopAG effector gene family, which restricts host range on citrus.