Identification of the lipoxygenase gene family from Vitis vinifera and biochemical characterisation of two 13-lipoxygenases expressed in grape berries of Sauvignon Blanc

Abstract

Lipoxygenases (LOXs) are a group of non-haem iron-containing dioxygenases that catalyse oxygenation of polyunsaturated fatty acids (PUFAs) and lipids, and initiate the formation of biologically active compounds known as oxylipins. Several plant oxylipins comprise important flavours and aromas in food and beverages. Analysis of the grape (Vitis vinifera L.) genome revealed that the grape LOX family consists of 18 individual members. Phylogenetic analysis places all except one of the identified grape LOXs into either a type II 13-LOX cluster or the type I 9-LOX cluster. Four LOX genes (VvLOXA, VvLOXO, VvLOXC, VvLOXD), representative of the major LOX groupings observed in the phylogenetic analyses, were selected for analysis of patterns of transcript abundance in berry tissues. VvLOXA and VvLOXO represent putative 13-LOXs, while VvLOXC represents a putative 9-LOX. VvLOXD represents a unique LOX that differs significantly from other characterised plant LOXs. All four LOXs exhibited a complex pattern of gene expression. Across all developmental stages, VvLOXA was the most abundant LOX and was expressed predominantly in berry skins. The expression pattern of VvLOXC and -D are more evenly distributed between seeds, pulp and skin, while VvLOXO is mostly expressed in the seed. Mechanical wounding and infection of berries with Botrytis cinerea Pers.: Fr resulted in rapid accumulation of VvLOXC and -O transcripts. VvLOXA expression decreased in diseased berries. Biochemical analysis of VvLOXA and -O recombinant proteins confirmed that these LOX genes encode functional 13-LOXs that exhibit different pH and temperature optima. Both enzymes showed activity with linoleic, linolenic and arachidonic acids.

The onset of grapevine berry ripening is characterized by ROS accumulation and lipoxygenase-mediated membrane peroxidation in the skin

“…Pinot Noir LOX was found predominantly in the thylakoid-enriched fraction, which was then used for tryptic digestion and MS analyses (Additional file 2). nanoLC/MS sequencing identified one peptide unambiguously matching Vv06s0004g01510, a 13-LOX differing at only five out of 901 residues from the recently described Sauvignon Blanc LOXA [41]. This result was confirmed by comparative MALDI-TOF/MS analysis performed on this fraction and on recombinant Vv06s0004g01510 protein.…”

Gene-Metabolite Networks of Volatile Metabolism in Airen and Tempranillo Grape Cultivars Revealed a Distinct Mechanism of Aroma Bouquet Production

“…Four LOX genes VvLOXA, VvLOXO, VvLOXC, and VvLOXD from the white grape cultivar Sauvignon Blanc have been isolated and characterized (Podolyan et al, 2010). The recombinant LOXA-TP and LOXO-TP proteins have been expressed and both enzymes were able to convert LnA into 13(S)-hydroperoxyoctadecatrienoic acid and LA into 13(S)- hydroperoxyoctadecadienoic acid.…”

Optimal hypobaric treatment delays ripening of honey peach fruit via increasing endogenous energy status and enhancing antioxidant defence systems during storage

“…However, in kiwifruit, most of the LOX genes showed decreased expression levels during the late stages of fruit development (Zhang et al, 2006). VvLOXC transcript abundance steadily declined during the initial stages of grape berry growth (Podolyan et al, 2010). Therefore, more information is needed on LOX gene expression in peach fruit induced by hypobaric treatment.…”