Components of the type IV secretion system (T4SS) identified in C. jejuni. Panels: (A) Identification of C. jejuni homologs to the structural components of the H. pylori Cag T4SS. Colors represent the percentage of protein identity for those proteins present as indicated in the figure legend. (B) Identification of potential T4SS genes in C. jejuni str. 81-176 genome that is represented by the chromosome, pVir and pTet; identical colors on pVir and pTet represent T4SS genes that encode for the same T4SS structural component, whereas different colors encode for T4SS structural genes unique to that particular plasmid. (C) Percentage of the >54,000 genomes in the PubMLST database that contain at least 2000 bp of the Campylobacter plasmid (pVir, pTet, or pCC31) that potentially encodes T4SS structural components.