FIG 2.

The AirSR TCS regulates the production of STX. All the strains were cultured for 24 h at 37° with shaking. S. aureus strains were cultured with 200 μM IPTG (A), 500 ng/ml ATc (B), and 250 ng/ml ATc (C). The OD₆₀₀ was measured after washing. STX was extracted in methanol, and the OD₄₅₀ was measured. Relative STX values were calculated as follows: OD₄₅₀/OD₆₀₀. The data represent the means ± standard errors of the mean (SEM) of the results of at least three independent experiments. JSAS909 is WCUH29 with an airS antisense RNA-expressing plasmid.