Conversion of dihomo-gamma-linolenic acid to mono- and dihydroxy acids by potato lipoxygenase: evidence for the formation of 8,9-leukotriene A3

• Published in: Archives of biochemistry and biophysics Vol. 279; no. 2; pp. 211 - 217
• Main Authors: Reddy, C.C. (University of Linkoping, Linkoping, Sweden), Bertler, C, Hammarstrom, S
• Format: Journal Article
• Language: English
• Published: United States 01.06.1990
• Subjects: 8,11,14-Eicosatrienoic Acid - metabolism; ACIDE LINOLENIQUE; ACIDO LINOLENICO; ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; Chromatography, High Pressure Liquid; ENZYMIC ACTIVITY; Fatty Acids, Unsaturated - metabolism; Hydroxyeicosatetraenoic Acids - metabolism; Leukotriene A4; Leukotrienes - biosynthesis; LINOLENIC ACID; Lipoxygenase - metabolism; METABOLISM; METABOLISME; METABOLISMO; OXIDACION; OXIDATION; oxidation products; Oxidation-Reduction; OXIDOREDUCTASES; OXIDORREDUCTASAS; OXYDATION; OXYDOREDUCTASE; reaction mechanism; SOLANUM TUBEROSUM; Solanum tuberosum - enzymology; Spectrophotometry, Ultraviolet; SRS-A - analogs & derivatives; SRS-A - metabolism
• ISSN: 0003-9861; 1096-0384

Evidence for the formation of a positional isomer of leukotriene (LT) C3 (8,9-LTC3) from dihomo-gamma-linolenic acid has been published (Hammarström, S. J. Biol. Chem. 256, 7712-7714, 1981). This report describes the conversion of dihomo-gamma-linolenic acid to a postulated intermediate in former reaction, 8,9-LTA3, by purified lipoxygenase from potato tubers. 8(S)-Hydroperoxyeicosatrienoic acid (8(S)-HPETrE) was the most abundant dioxygenation product formed followed by 11-, 15-, and 12-HPETrEs (in decreasing order of abundance). In addition, 8(S),15(S)- plus 8(S), 15(R)-dihydroperoxyeicosatetraenoic acid (DiHPE-TrE) (EZE), and 8(S),15(S)- plus 8(S),15(R)-dihydroxy-eicosatetraenoic acid (DiHETrE) (EEE) were generated. Under anaerobic conditions only the latter two isomers of 8,15-DiHETrE (EEE) were obtained from 8-HPETrE. The results suggest that 8,9-LTA3 is synthesized by the sequential action of 8- and 11-lipoxygenase activities associated with the potato enzyme.