Macrowine 2021
IVES 9 IVES Conference Series 9 Cytochrome P450 CYP71BE5 from grapevine (Vitis vinifera) catalyzes the formation of the spicy aroma compound, (-)-rotundone

Cytochrome P450 CYP71BE5 from grapevine (Vitis vinifera) catalyzes the formation of the spicy aroma compound, (-)-rotundone

Abstract

(-)-Rotundone, an oxygenated sesquiterpene, is a potent odorant molecule with a characteristic spicy aroma existing in various plants including grapes1. It is considered as a significant compound notably in wines and grapes because of its low sensory threshold (16 ng L-1 in red wine, 8 ng L-1 in water) and aroma properties. (-)-Rotundone was first identified in red wine made from the grape cultivar Syrah (regionally called Shiraz) in Australia1, and then it was found in several grape varieties such as Duras, Grüner Veltliner, Schioppettino and Vespolina from Europe2, 3. Several environmental factors affecting the accumulation of (-)-Rotundone during the grape maturation, were reported such as ambient temperature4, soil properties and topography5, soil moisture from irrigation and light exposure in the bunch zone by leaf removal2. However, the biosynthetic pathway of (-)-rotundone in grapevine has been unclarified to date. In this study, we report the identification of VvSTO2 as a α-guaiene 2-oxidase which can transform α-guaiene to (-)-rotundone in the grape cultivar Syrah6. It is a cytochrome P450 (CYP) belonging to the CYP 71BE subfamily, which overlaps with the very large CYP71D family and, to the best of our knowledge, this is the first functional characterization of an enzyme from this family. VvSTO2 generated (-)-rotundone as the major reaction product with α-guaiene, and presumably (2R)-rotundol and (2S)-rotundol as the intermediate compounds to synthesize (-)-rotundone were found at trace levels in vitro enzyme assay. This result suggests that this enzyme can catalyze a one-step oxidation of α-guaiene to (-)-rotundone or a two-step oxidation via a rapid second oxidation from (2R)-rotundol and (2S)-rotundol to (-)-rotundone. VvSTO2 was expressed at a higher level in the Syrah grape exocarp (skin) in accord with the localization of (-)-rotundone accumulation in grape berries. α-Guaiene was also detected in the Syrah grape exocarp at an extremely high concentration. These findings suggest that (-)-rotundone accumulation is regulated by the VvSTO2 expression along with the availability of α-guaiene as a precursor. VvSTO2 expression during grape maturation was considerably higher in Syrah grape exocarp compared to Merlot grape exocarp, consistent with the patterns of α-guaiene and (-)-rotundone accumulation. On the basis of these findings, we propose that VvSTO2 may be a key enzyme in the biosynthesis of (-)-rotundone in grapevines by acting as a α-guaiene 2-oxidase. [References] [1] Wood, C., et al. 2008. J. Agric. Food Chem. 56, 3738-44. [2] Geffroy, O., et al. 2014. Aust. J. Grape Wine Res. 20, 401-408. [3] Mattivi, F., et al. 2011. Rapid Commun. Mass Spectrom. 25, 483-8. [4] Caputi, L., et al. 2011. J. Agric. Food Chem. 59, 5565-71. [5] Scarlett, N.J., et al. 2014. Aust. J. Grape Wine Res. 20, 214-222. [6] Takase, H., et al. 2015. J. Exp. Bot, in press.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Hideki Takase*, Akira Shinohara, Akira Shinohara, Gen Ikoma, Hideyuki Shinmori, Hironori Kobayashi, Hironori Matsuo, Hiroshi Saito, Kanako Sasaki, Ryoji Takata

*Research Laboratories for Wine

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Sensory and nephelometric analysis of tannin fractions obtained by ultrafiltration of red wines

The assessment of red wine mouthfeel relies primarily on the sensory description of its tannic properties. This evaluation could be improved by gaining a better understanding of the physicochemical properties of these tannins. Hence, the objectives of the present study were threefold: (1) to gain an insight into the sensory properties of subpopulations of proanthocyanidic tannins of different molecular sizes obtained through several ultrafiltration steps, (2) to quantify the kinetics of haze formation of these proanthocyanidic tannins in a dynamic polyvinylpyrrolidone (PVP) precipitation test, (3) to determine whether a correlation exists between the sensory and the precipitation data.

Read More

Anti/prooxidant activity of wine polyphenols in reactions of adrenaline auto-oxidation

Adrenaline (epinephrine) belongs to catecholamine class. It is a neurotransmitter and both a hormone which is released by the sympathetic nervous system and adrenal medulla in response to a range of stresses in order to regulate blood pressure, cardiac stimulation, relaxation of smooth muscles and other physiological processes. Adrenaline exhibits an effective antioxidant capacity (1). However, adrenalin is capable to auto-oxidation and in this case it generates toxic reactive oxygen intermediates and adrenochrome. Under in vitro conditions, auto-oxidation of adrenaline occurs in an alkaline medium (2).

Read More

Anthropogenic factors in modulations of fungal populations from grapes to wines and their repercussions on wine characteristics

The effects of anthropogenic activities on vineyard (different plant protections) and in winery
(pressing/clarification step, addition of sulfur dioxide) on fungal populations from grape to wine were studied. The studied anthropogenic activities modify the fungal diversity. Thus, lower biodiversity of grapes from organic modality was measured for the three vintages considered compared to biodiversity from ecophyto modality and conventional modality. The pressing / clarification steps strongly modify fungal populations and the influence of the winery flora is highlighted.

Read More

Improving the phenolic composition of cv tempranillo wines by blending grapes of different ripening state

The aim of this work was to reduce the alcohol content of Tempranillo wine. Tempranillo wines were produced by grapes harvested at different ripening dates (August 11 which was 21 oBrix and September 28 with 25 oBrix). At the second date, the Tempranillo wines were elaborated as follows: grapes were destemmed, crushed and collected into 50 L stainless-steel vats. Before preferementative maceration in cold, 50 % (M1) and 70 % (M2) of the must have been replaced by the same percentage of must from the first harvest. In addition, a control wine (C) was performed with only grapes from the second harvest.

Read More

Effect of nanofiltration on the chemical composition and wine quality

In Enology the conventional processes of filtration for clarification and stabilization are giving place to alternative membrane processes, including nanofiltration (NF). Furthermore, the increased alcohol content in wines recorded in recent years became an important issue for all the main wine producing countries. Among techniques available to the wine industry to reduce the ethanol content, NF is certainly one of the newest. This study is focused on the evaluation of NF influence on wine physical-chemical composition, including mineral content, which in accordance to our best knowledge is a novelty.

Read More