FIG. 4.

The presence of IVSs for the 16 SARC strains representing the eight Salmonella subgroups; genetic distance was determined as described in the legend to Fig. 3 (7). The total number of IVSs in helix 25 and helix 45 was determined by PCR to detect IVSs and also by analysis of RNA to show fragmentation; the inferred number of IVSs from both methods was the same for each strain. Species and SARC numbers are listed in Table 2.