LPS and O-antigen synthesis. (A) Model representing LPS and O-antigen synthesis in Xanthomonas. Each of the numbers in this panel correspond to the same numbers in panel B. The model is based on the one described by Vorholter et al.  for X. campestris. Genes for products 12, 14, 17 and 18 are absent from XAC, XauB and XauC. (B) Genomic context of the LPS synthesis-related genes in XAC and X. campestris. The flanking regions (in pink) are conserved. The central region is not conserved between X. campestris on the one hand and XAC, XauB and XauC on the other. Moreover there is a group of genes that is shared and syntenic between the CC-species (in orange) and another (in green) that is specific to XAC (XACSR18). (C) A XAC mutant for gene wzt showed a different virulence pattern . The wzt homolog in XauB and XauC does not have the C-terminal portion when compared to the XAC wzt gene. (D) Region XACSR1 contains several genes related to LPS biosynthesis. Numbers above gene arrows correspond to the annotations immediately below in this panel.