Fig. 4

Replacement of the PabI family of RM system with hrgC. a Distribution of the PabI homolog vs. hrgC gene in each population of H. pylori. Only strains that have been completely sequenced and deposited in RefSeq were counted. Analyzed strains are documented in Additional file 2: Table S2. b Genome map comparison around hrgC genes. Orthologous genes are shown as boxes with the same color and pattern. White boxes represent hrgC genes. c Distribution of the PabI homolog vs. hrgC gene in East Asia subgroups of H. pylori. Only strains reported in Yahara et al. [17] are analyzed. d Alignment of HrgC proteins. The C-terminal 15 residues of the Escherichia HrgC protein are omitted. Roman numbers right of the H. pylori and H. acinonychis strain names indicate the hrgC lineages shown in Fig. 5. Accession numbers are as follows. Puno120, AEN15115; F30, BAJ56916; OK310, BAM98251; oki102, AHN34853; HpA-14, WP_000301367; G27, ACI26869; Sheeba, YP_665190; Fusobacterium, YP_008019852; Bacillus, EJS64418; Escherichia, AIT14382. e Geographic distribution of hrgC gene. Three lineages of hrgC are colored differently. Green arrows indicate two human migration routes