Figure 3.—

Schematic of IS150 insertions in the uspA/B intergenic region. Block arrows indicate the direction of transcription for each gene and are to scale except for the IS150 element. Eight of the 15 FTG populations had at least one tested clone with an IS150 insertion in the exact same position and orientation, 34 bp upstream of the uspB start codon. This insertion generated a 3-bp duplication at the target site and is 95 bp downstream of the putative uspB promoter (σ^S). The IS150 element has at least one possible promoter-like sequence directed outward (Schwartz et al. 1988) toward uspB. See supplemental Table 5 for information on the location of this mutation and the number of mutated clones in each population.