Pervasive, genome-wide positive selection leading to functional divergence in the bacterial genus Campylobacter

Distribution of the positively selected genes in the 14 tested lineages of Campylobacter. The genes and lineages were sorted following a correspondence analysis. (Black dots) Genes under positive selection, (gray circles of different diameters, bottom) number of lineages under positive selection (PS) for a specific gene. (CCF) C. consisus, C. curvus, and C. fetus ancestral lineage; (JCU) C. jejuni, C. coli, and C. upsaliensis ancestral lineage; (CC) C. consisus and C. curvus ancestral lineage; (CCFH) C. consisus, C. curvus, C. fetus, and C. hominis ancestral lineage; (JC) C. jejuni and C. coli ancestral lineage; (JCUL) C. jejuni, C. coli, C. upsaliensis, and C. lari ancestral lineage.