Studies on the Substrate Specificity of Soybean Lipoxygenase-1 Using an Entire Series of (ω3 Z,ω6 Z ,ω9 Z)-C12~ C22-Trienoic Acids and -Trienols

Substrate recognition mechanism of soybean lipoxygenase-1 (L -1) was studied by using an entire series of (ω3Z,ω6Z,ω9Z)-C12~C22-trienoic acids and -trienols. The maximum activity of L-1 was obtained with C20-trienoic acid of all the substrates used. Among trienols, the maximum activity was obtained with C15-trienol. Analysis of the products obtained by the reaction of these substrates with L-1 revealed that trienoic acids were oxygenated mostly at ω6 position independently on the chain length. The hydroperoxy group at ω6 was introduced at (S)-configuration with over 98% enantioselectivity. Although the products formed from most trienols were also selectively oxygenated at ω6 position, only C15-trienol was oxygenated at both ω6 and ω10 positions in the ratio of ω6/ω10 = 48/52.