Fig. 3

COG category distribution within S. Napoli genomes vs all Clade A genomes. Distribution of COG categories in S. Napoli (left panel): core genes (yellow) and accessory genes (gray). Distribution of COG categories in the entire Salmonella dataset (right panel): core genes (orange) and accessory genes (blue). Results are reported after genes with no COG category assigned were removed. x-axis represents the percentage of genes belonging to each category. Among the categorized genes, the S. Napoli core genome dataset shows several categories having a similar occurrence, with none of them dominating over the others. Conversely, the S. Napoli accessory genome is largely composed by genes, whose products could be assigned to the X (Mobilome: prophages, transposons), G (Carbohydrate transport and metabolism) and L (Replication, recombination and repair) COG categories. These results suggest that the accessory genome comprises both mobile elements, often involved in virulence/pathogenicity, and genes involved in core metabolic functions and defense mechanisms. No relevant difference in COGs occurrence distribution can be highlighted when comparing the S. Napoli dataset and the entire datatset: similar patterns can be found both in core- and accessory- genome COG frequency distribution