FIGURE 8.

Comparison of the aerobic and anaerobic reactions of soybean LOX-1 with 15S-HPETE. Aerobic reaction is initiated by the H-7 and H-10 hydrogen abstractions (pro-R hydrogens, designated as in arachidonic acid rather than 15S-HPETE) with 15S-HPETE in the reversed orientation, antarafacial oxygenation giving the 5S,15S-diHPETE and 8S,15S-diHPETE products, respectively (6, 44, 45). Anerobically, analogous hydrogen abstractions can account for formation of the cyclopropyl epoxide and 14,15-LTA₄, respectively, followed by non-enzymatic hydrolysis to give the stable diol end products.