Figure 6.

Deuterium exchange in the PLAT domain in 15-LOX-2 upon lipid binding. Addition of the substrate and product to 15-LOX-2 resulted in unexpected decreases in the level of H/D exchange in the PLAT domain. H/D exchange was performed for 15-LOX-2 in four different states: (1) 15-LOX-2 with Ca²⁺ present (blue squares), (2) 15-LOX-2 with Ca²⁺ and AA present (green diamonds), (3) 15-LOX-2 with Ca²⁺ and 15-HpETE present (red circles), and (4) chelating agent treated 15-LOX-2 with AA present (black triangles). The exchange profiles for peptides exhibiting changes of >10% after exchange for 2 min are shown: (A) peptide 67–87, (B) peptide 54–66, and (C) peptide 45–52.