Fatty acid hydroperoxides biotransformation by potato tuber cell-free extracts

• Published in: Journal of plant physiology Vol. 159; no. 10; pp. 1055 - 1060
• Main Authors: Fauconnier, Marie-Laure, Delcarte, Jerôme, Jaziri, Mondher, Jardin, Patrick d.u., Marlier, Michel
• Format: Journal Article Web Resource
• Language: English
• Published: Jena Elsevier GmbH 01.10.2002; Elsevier; Elsevier Science Ltd
• Subjects: aldehyde; Bioconversions. Hemisynthesis; Biological and medical sciences; Biologie végétale (sciences végétales, sylviculture, mycologie...); Biotechnology; fatty acid hydroperoxide; Fundamental and applied biological sciences. Psychology; heterolytic and homolytic hydroperoxide cleavage; hydroperoxide lyase; Life sciences; Methods. Procedures. Technologies; Phytobiology (plant sciences, forestry, mycology...); potato tuber; Sciences du vivant; Solanum tuberosum L; aldehyde; potato tuber; Solanum tuberosum L; heterolytic and homolytic hydroperoxide cleavage; hydroperoxide lyase; fatty acid hydroperoxide; Enzyme; Solanum tuberosum; Reaction product; Hydroperoxide; Fatty acids; Characterization; Dicotyledones; Biotransformation; Angiospermae; Tuber; Spermatophyta; Oxidoreductases; Tuber plant; Solanaceae; Lipoxygenase; Cell free system
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1078/0176-1617-00681

Cleavage of 13-HPOD, 13-HPOT, 9-HPOD and 9-HPOT by potato tuber cell-free extracts was investigated. 13-HPOD and 13-HPOT enzymes were degraded almost completely while 9-HPOD and 9-HPOT were partially transformed. GC-MS analysis of the volatile compounds formed during the reactions revealed that ( Z)-3 hexenal, (E)-2-hexenal, pentenols and dimers of pentene were obtained from 13-HPOT while from 13-HPOD hexanal and pentan-1-ol were formed. No volatile was found when 9-HPO isomers were used as substrate, but colneleic acid was produced. When Triton X-100 was omitted in the extraction buffer, only pentenols and dimers of pentene were identified from 13-HPOT and pentan-1-ol from 13-HPOD. Our results reveal that potato tubers that contain Lox, which forms mainly 9-HPO, are able to metabolise the four HPO isomers. Moreover, 13-HPO cleaving activities are due to two distinct enzymatic systems based on, respectively, homolytic and heterolytic mechanisms. The fact that oxygenation of reaction medium dramatically decreases the amount of product resulting from homolytic cleavage strengthens the hypothesis of an anaerobic reaction due to Lox.