Nethaji Janeshawari Gallage
University of Copenhagen, Denmark
Title: The elucidation and bioengineering of the vanillin biosynthesis in the vanilla orchid
Biography
Biography: Nethaji Janeshawari Gallage
Abstract
Vanilla and its key flavour component vanillin, is a universally appreciated flavour, a global delicacy and probably the most popular plant natural product, being derived from the seedpods of the orchid Vanilla planifolia and other related Vanilla species. The flavour and fragrance profile of the vanilla extract contains more than 200 components. Vanillin (3-methoxy-4-hydroxybenzaldehyde) is the main flavor compound in the vanilla extract and is the basis and an additive of sweets, ice creams, soft drinks and many more products in the food, beverage and pharmaceutical industry. Despite its popularity, the biosynthetic pathway of vanillin has remained elusive until now. Our studies during last 4 years reveal how the vanilla orchid produces the most popular aroma compound in the world. A single hydratase/lyase type enzyme designated vanillin synthase (VpVAN) catalyzes direct conversion of ferulic acid and its glucoside into vanillin and its glucoside, respectively. The enzyme shows high sequence similarity to cysteine proteinases and is strictly specific to the substitution pattern at the aromatic ring. Transient expression of VpVAN in tobacco and stable expression in barley in combination with the action of endogenous alcohol dehydrogenases and UGTs result in vanillyl alcohol glucoside formation from endogenous ferulic acid (Gallage et al., 2014 Nature communications, Gallage and Møller 2015, Molecular plant).