Figure 4.

In vitro aerobactin pathway turnover frequency. A, standard curve relating HPLC A_{218 nm} to aerobactin mass. The data points were fit with a linear regression best-fit line. B, overlaid A_{218 nm} HPLC traces of the aerobactin peak at progressive in vitro reconstitution reaction times using 8 μm enzymes. C, progress curves of the aerobactin reconstitution at three enzyme concentrations (2, 4, and 8 μm). The linear regions were fit with regression lines to estimate pathway velocity.