Figure 5.
Turnover rates of bimodular chimeric PKSs harboring a chimeric chain elongation interface. Bimodular PKSs comprised of LDD(4),(5) KS1-AT1-SZ3, and variable SZ4-KRn-ACPn-Modulen+1-TE constructs. Construct design and the predicted triketide lactone products are shown next to the measured turnover rate of each system. All initial rate data was obtained at 2 μM enzyme concentration and nonlimiting concentrations of propionyl-CoA, methylmalonyl-CoA, malonyl-CoA (RIFS M2 is malonyl specific), and NADPH. Turnover analysis was performed on two individually purified proteins per construct (back and white dots). Measurements were performed in triplicate, and the grand mean is indicated.