Hamberg M
Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
Lipids. 1998 Nov;33(11):1061-71. doi: 10.1007/s11745-998-0306-7.
[1-14C]alpha-Linolenic acid was incubated with a particulate fraction of homogenate of leaves of the meadow buttercup (Ranunculus acris L.). The main product was a divinyl ether fatty acid, which was identified as 12-[1'(Z),3'(Z)-hexadienyloxy]-9(Z),11(E)-dodecadienoic acid. Addition of glutathione peroxidase and reduced glutathione to incubations of alpha-linolenic acid almost completely suppressed formation of the divinyl ether acid and resulted in the appearance of 13(S)-hydroxy-9(Z), 11(E),15(Z)-octadecatrienoic acid as the main product. This result, together with the finding that 13(S)-hydroperoxy-9(Z), 11(E),15(Z)-octadecatrienoic acid served as an efficient precursor of the divinyl ether fatty acid, indicated that divinyl ether biosynthesis in leaves of R. acris occurred by a two-step pathway involving an omega6-lipoxygenase and a divinyl ether synthase. Incubations of isomeric hydroperoxides derived from alpha-linolenic and linoleic acids with the enzyme preparation from R. acris showed that 13(S)-hydroperoxy-9(Z),11(E)-octadecadienoic acid was transformed into the divinyl ether 12-[1'(Z)-hexenyloxy]-9(Z), 11(E)-dodecadienoic acid. In contrast, neither the 9(S)-hydroperoxides of linoleic or alpha-linolenic acids nor the 13(R)-hydroperoxide of alpha-linolenic acid served as precursors of divinyl ethers.
将[1-¹⁴C]α-亚麻酸与毛茛（毛茛属）叶片匀浆的微粒部分一起温育。主要产物是一种二乙烯基醚脂肪酸，其被鉴定为12-[1'(Z),3'(Z)-己二烯氧基]-9(Z),11(E)-十二碳二烯酸。在α-亚麻酸温育体系中添加谷胱甘肽过氧化物酶和还原型谷胱甘肽几乎完全抑制了二乙烯基醚酸的形成，并导致13(S)-羟基-9(Z),11(E),15(Z)-十八碳三烯酸作为主要产物出现。这一结果，连同13(S)-氢过氧-9(Z),11(E),15(Z)-十八碳三烯酸作为二乙烯基醚脂肪酸的有效前体这一发现，表明毛茛叶片中二乙烯基醚的生物合成通过一个两步途径发生，该途径涉及ω6-脂氧合酶和二乙烯基醚合酶。将源自α-亚麻酸和亚油酸的异构氢过氧化物与毛茛的酶制剂一起温育表明，13(S)-氢过氧-9(Z),11(E)-十八碳二烯酸转化为二乙烯基醚12-[1'(Z)-己烯氧基]-9(Z),11(E)-十二碳二烯酸。相反，亚油酸或α-亚麻酸的9(S)-氢过氧化物以及α-亚麻酸的13(R)-氢过氧化物均不作为二乙烯基醚的前体。
