Comparison of type III secretion system cluster, its associated type III effector genes and helper genes of three draft genomes with already sequenced xanthomonads. Type III secretion gene clusters in five strains are shown. Boxes of the same colour indicate orthologous genes. Genes of special interest discussed in the paper are labeled. Xp has near identical hrp cluster as Xcv; Xv and Xg contain mosaic hrp cluster with organization and gene content similar to Xcc, but associated effectors are similar to Xcv along with novel effector gene associated with the cluster.