Figure 4.

Steady-state kinetics of oxidation of alkyl sulfates and fatty acids by P450_BM-3. Measurements were based on rates of oxidation of NADPH and the lines show hyperbolic fits to the data points. A. Dodecyl sulfate (C₁₂SO₄): k_cat 980 ± 20 min⁻¹, K_m 28 ± 1 μM; k_cat/K_m 36 ± 2 μM⁻¹ min⁻¹ (7.7 × 10⁵ M⁻¹ s⁻¹). B. Tetradecyl sulfate (C₁₄SO₄): k_cat 1940 min⁻¹, K_m 4.2 ± 0.6 μM, k_cat/K_m 460 ± 60 μM⁻¹ min⁻¹ (3 × 10⁶ M⁻¹ s⁻¹). C. Palmitic acid: k_cat 220 ± 20 min⁻¹, K_m 67 ± 8 μM, k_cat/K_m 3.3 ± 0.3 × 10⁵ μM⁻¹ min⁻¹ (5.5 × 10⁴ M⁻¹ s⁻¹). D. N-Palmitoylglycine: k_cat 595 ± 40 min⁻¹, K_m 9 ± 2 μM, k_cat/K_m 66 ± 12 μM min⁻¹ (1.1 × 10⁶ M⁻¹s⁻¹).