Colneleic acid

Faueonnier, M. L., Williams, T. D., Marlier, M., Welti, R. (2003b). Potato tuber phospholipids contain colneleic acid in the 2-position. FEBS Fett., 538, 155-158. 

T. Galliard et al. Novel divinyl ether fatty acids in extracts of Solanum tuberosum, Chem. Phys. Lipids, 1973, 11, 173-180. L. Crombie et al, An isotopic study of the enzymic conversion of linoleic acid into colneleic acid and carbon chain fracture the origin of shorter chain aldehydes. J. Chem. Soc. (Perkin 1) 1991, 567-575. A. GrechMn, Prog. Recent developments in the biochemistry of the plant lipoxygenase pathway, Progress in Lipid Research, 1998, 37, 317-352. 

Fatty acid hydroperoxides generated by plant lipoxygenases from linoleic and linolenic acids are known to serve as substrates for a divinyl ether synthase which produces divinyl ether fatty acids. Up to date divinyl ethers were detected only within the plant kingdom. The discovery of that class of compounds dates back to 1972, when the structures of two ether C18 fatty acids generated by homogenates of the potato tuber wee described. These compounds, named colneleic acid (from linoleic acid) and colnelenicacid (from linolenic acid), could be also produced in potato leaves and tomato roots by rearrangement of 9-hydroperoxides. 

A novel enzyme system, so far only identified in potato tubers, converts the 9-hydroperoxides of linoleic and linolenic acids to divinyl ether derivatives (colneleic and colnelenic acids, respectively) in which an atom of oxygen is inserted into the fatty acid chain (Galliard and Phillips, 1972 Galliard... 

Colneleic and colnelenic acids are degraded by oxidative cleavage of the ether to form aldehydic fragments. The. degradation is catalyzed by an enzyme in potato tubers but also occurs in the presence of Fe " ions and some nonheme proteins, e.g., ferredoxin. 

Isomers of colneleic and colnelenic acids were isolated from homogenates of leaves of Clematis vitalba (Ranunculaceae). 

Up to now this reaction has only been observed with extracts of potato tubers. The 9-hydroperoxy isomers of linoleic and linolenic acids appear to be the exclusive substrates for the reaction. During the reaction one of the hydroperoxy oxygen atoms is inserted into the fatty acid chain to form a divinyl ether linkage. The products from linoleic and linolenic acids have been termed colneleic and colnelenic acids, respectively (5) (Fig. 2). 

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