Comparison of the FeHm-regulated genes in Rd KW20, NTHi R2866 and Hib 10810. (A) Genes that are repressible by iron and heme. (B) Genes that are inducible by iron and heme. The number under each isolate name indicates the total number of genes determined to be regulated for that isolate under the appropriate conditions. Numbers in parentheses indicate the number of genes that are regulated that are distinct to those isolates i.e. the gene is not present in the genome of the other isolate(s). The data show that there is a core set of 37 genes that are present in and regulated in all three isolates for both the FeHm-repressible and the FeHm-inducible gene sets.