Xanthomonas

Xanthomonas is a genus of Proteobacteria, many of which cause plant diseases.

The Xanthomonas genus has been subject of numerous taxonomic and phylogenetic studies and was first described as Bacterium vesicatorium as a pathogen of pepper and tomato in 1921. Dowson later reclassified the bacterium as Xanthomonas campestris and proposed the genus Xanthomonas.Xanthomonas was first described as a monotypic genus and further research resulted in the division into two groups, A and B. Later work using DNA:DNA hybridization has served as a framework for the general Xanthomonas species classification. Other tools, including multilocus sequence analysis and amplified fragment-length polymorphism, have been used for classification within clades. While previous research has illustrated the complexity of the Xanthomonas genus, recent research appears to have resulted in a clearer picture. More recently, genome-wide analysis of multiple Xanthomonas strains mostly supports the previous phylogenies.