Table 3 Functional groupings of essential genes which are significantly represented in Campylobacter strains and species. Table shows the COG letter code and description and if the COG is significantly over-represented within essential genes compared to the whole genome for each strain tested in this study. Significance was called using Fisher's exact test with a p-value of less than 0.05. ns denotes not significant, * denotes P ≤ 0.05, ** denotes P ≤ 0.01, *** denotes P ≤ 0.001, **** denotes P ≤ 0.0001
