Figure 5.

Substrate specificities of recombinant wild-type castor Δ9–18:0-ACP desaturase (left) and the mutant L118W (right) assayed with 14:0-, 16:0-, and 18:0-ACPs. Partially purified enzymes from E. coli were assayed as described in Methods. The maximum reaction rate (100%) was 823 nmol min⁻¹ mg⁻¹ protein for the wild-type enzyme and 28.8 nmol min⁻¹ mg⁻¹ protein for the L118W mutant.