Neoxanthin
Encyclopedia
Neoxanthin is a carotenoid
and xanthophyll
. In plants, it is an intermediate in the biosynthesis
of the plant hormone abscisic acid
. It is produced from violaxanthin
by the action of neoxanthin synthase
.
Carotenoid
Carotenoids are tetraterpenoid organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some bacteria, and some types of fungus. Carotenoids can be synthesized fats and other basic organic metabolic building...
and xanthophyll
Xanthophyll
Xanthophylls are yellow pigments that form one of two major divisions of the carotenoid group. The name is from Greek xanthos + phyllon , due to their formation of the yellow band seen in early chromatography of leaf pigments...
. In plants, it is an intermediate in the biosynthesis
Biosynthesis
Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...
of the plant hormone abscisic acid
Abscisic acid
Abscisic acid , also known as abscisin II and dormin, is a plant hormone. ABA functions in many plant developmental processes, including bud dormancy. It is degraded by the enzyme -abscisic acid 8'-hydroxylase.-Function:...
. It is produced from violaxanthin
Violaxanthin
Violaxanthin is a natural xanthophyll pigment with an orange color found in a variety of plants including pansies. It is biosynthesized from zeaxanthin by epoxidation. As a food additive it used under the E number E161e as a food coloring; it is not approved for use in the EU or USA however is...
by the action of neoxanthin synthase
Neoxanthin synthase
In enzymology, a neoxanthin synthase is an enzyme that catalyzes the chemical reaction:Hence, this enzyme has one substrate, violaxanthin, and one product, neoxanthin....
.