Figure 1.

Characteristics of the pangenome of the Brucella genus. (A) The pangenome composition. (B) The numbers of core gene families, accessory gene families and strain-specific genes in each strain. (C) The accumulation curves of the pangenome and core genome of the Brucella genus. The blue curve shows an open pangenome; the deduced pangenome size was y = 474.62x^0.48 + 2333.18. The red curve shows the core genome, and the deduced core genome size was y = 1404.61e^–0.01x + 1397.95. (D) The tanglegram shows the differences in the topological structures between the core tree and the pan tree. A core tree was created based on core single-copy orthologues. The pan tree was created based on a binary panmatrix (gene presence/absence matrix). (E) The accumulation curves of the pan-Chr I and pan-Chr II of the Brucella genus. The dark color represents Chr I, while the light color represents Chr II. (F) The distribution and COG functional characteristics of the core and accessory gene families on Chr I and Chr II. * t–test p < 0.05.