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…

Screening sensory-directed methodology for the selection of non-saccharomyces wine yeasts based on perceived aroma quality

The present work contributes by developing a rapid sensory-directed methodology for the screening and selection of high quality wines with different sensory profiles Therefore, Verdejo and Tempranillo musts were fermented with 50 different yeasts each under controlled laboratory conditions. Resulting samples were firstly categorized according to five levels of quality by a panel of wine professionals (Sáenz-Navajas, Ballester et al. 2013). Higher quality samples were described by flash profiling by a semi-trained panel
(Valentin, Chollet et al. 2012) and most distinctive samples were screened by gas chromatography-olfactometry (GC-O) (López, Aznar et al. 2002).

Read More

Impact of some agronomic practices on grape skins anthocyanin content

Wine colour is the first quality characteristic to be assessed, especially regarding red wines. Anthocyanins are very well known to be the main responsible compounds for red wine colour. Red cultivars can synthesize and accumulate anthocyanins in berry skin to express their colour. However, anthocyanin accumulation is often influenced by a series of factors, such as genetic regulation, phytohormones, environmental conditions and viticultural management.

Read More

Prediction of the production kinetics of the main fermentative aromas in alcoholic fermentation

Fermentative aromas (especially esters and higher alcohols) highly impact the organoleptic profile of young and white wines. The production of these volatile compounds depends mainly on temperature and Yeast Available Nitrogen (YAN) content in the must. Available dynamic models predict the main reaction
(bioconversion of sugar into ethanol and CO2 production) but none of them considers the production kinetics of fermentative aroma compounds during the process of fermentation. We determined the production kinetics of the main esters and higher alcohols for different values of initial YAN content and temperature, using an innovative online monitoring Gas Chromatography device.

Read More

Influence of wood chips addition during alcoholic fermentation on wine phenolic composition

This study investigates the effect of wood chips addition during the alcoholic fermentation on the phenolic
composition of the produced wines. A series of wood chips, originating from American, French, Slavonia
oak and Acacia were added at the beginning of wine alcoholic fermentation. Besides, a mixture consisting
of 50% French and 50% Americal oak chips were added during the experimentation. The wine samples
were analyzed one month after the end of malolactic fermentation, examining various chemical
parameters such as total anthocyanins, total phenolic content, tannins combined with protein (BSA) and
ellagitannin content.

Read More

Red wine substituted esters involved in fruity aromatic expression: an enantiomeric approach to understand their sensory impact and their pathway formation

Among red wines ethyl esters, those from short hydroxylated and branched-chain aliphatic acids constitute a family with a particular behavior and sensory importance. They have been previously discussed in the literature [1] and recent studies have established that some of them were strongly involved in of red wines’ fruity aroma [2]. As some among them have an asymmetrical carbon atom, it seemed important to separate their different enantiomers to obtain an accurate assessment of their organoleptic impact. Three chiral esters have been identified, presenting alkyl and/or hydroxyle substituants: ethyl 2-hydroxy-4-methylpentanoate, ethyl 2-methylbutanoate, and ethyl 3-hydroxybutanoate.

Read More