FIG 2 .

Induction of tolerance genes is toxic above 10 µM IPTG. E. coli DH1 harboring each of the 40 genes cloned into pBbA5k was induced with 0, 10, 50, 100, and 250 µM IPTG and grown for 21 h. For each strain, the OD₆₀₀ was measured and normalized to growth without IPTG. The only concentration of IPTG that did not decrease growth across all strains was 10 µM IPTG; thus, all subsequent tolerance assays were performed with 10 µM IPTG. For OD₆₀₀ data for a specific strain, see Fig. S1 in the supplemental material.