Hydroperoxide lyase cascade in pea seedlings: Non-volatile oxylipins and their age and stress dependent alterations

• Published in: Phytochemistry (Oxford) 2011-04, Vol.72 (4-5), p.356-364
• Main Authors: Mukhtarova, Lucia S., Mukhitova, Fakhima K., Gogolev, Yuri V., Grechkin, Alexander N.
• Format: Article
• Language: English
• Subjects: acids; Aldehyde-Lyases - metabolism; allene; Cytochrome P-450 Enzyme System - metabolism; ethers; gas chromatography; Gas Chromatography-Mass Spectrometry; Humans; Hydroperoxide lyase; Intramolecular Oxidoreductases - metabolism; leaves; Lipoxygenase pathway; Lipoxygenases - metabolism; mass spectrometry; Molecular Structure; oxides; Oxylipins - chemistry; Oxylipins - metabolism; Oxylipins profiles; Pea (Pisum sativum L.); peas; Pisum sativum; Pisum sativum - enzymology; plant age; Plant Proteins - metabolism; roots; seedlings; Seedlings - enzymology; Stress response
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2011.01.013

The lipoxygenase pathway in pea seedlings operates predominantly through the hydroperoxide lyase cascade and produces the age- and stress-dependent array of oxylipins including some compounds, e.g. the 4-hydroxy-traumatic acid. [Display omitted] ► Lipoxygenase pathway in pea seedlings operates through the hydroperoxide lyase route. ► 4-Hydroxy-traumatic acid and three other new oxylipins have been identified. ► Oxylipin profiles exhibit the significant age and stress dependent alterations. ► Azelaic acid is specifically accumulated during the plant–bacteria interaction. The profiles of non-volatile oxylipins of pea (Pisum sativum) seedlings were examined by gas chromatography–mass spectrometry after invitro incubation with α-linolenic acid. The 13-lipoxygenase/hydroperoxide lyase (HPL) products were predominant in the leaves, while the roots possess both 13- and 9-HPL products. Allene oxide synthase (AOS) and divinyl ether synthase (DES) products were not detected in the leaves or in the roots of any age. The HPL cascade produces a diversity of oxylipins, including the compounds (2E)-4-hydroxy-traumatic, (10E)-9,12-dihydroxy-10-dodecenoic and 9,12-dihydroxydodecanoic acids, as well as (2E)-4-hydroxy-2-nonenoic acid, which has not yet been detected in plants. Oxylipin patterns were altered by infection, water deficit, as well as by plant age. Infection caused the specific strong accumulation of azelaic (nonane-1,9-dioic) acid in the leaves. The azelaic acid content in the aged (14 and 18day-old) leaves was significantly higher than in the younger leaves. Water deficit induced the accumulation of (2E)-4-hydroxy-2-nonenoic acid and (2E)-traumatic acid in the roots. Results demonstrate that: (1) the HPL cascade is the predominant branch of the lipoxygenase pathway in pea seedlings; (2) the HPL products may have the regulatory role both in growth control and adaptation.