Hosta

In enzymology, a flavonol synthase (EC 1.14.11.23) is an enzyme that catalyzes the following chemical reaction :

dihydroflavonol + 2-oxoglutarate + O
₂ a flavonol + succinate + CO
₂ + H₂O

The 3 substrates of this enzyme are dihydroflavonol, 2-oxoglutarate, and O₂, whereas its 4 products are flavonol, succinate, CO₂, and H₂O.

This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O
₂ as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O
₂ with 2-oxoglutarate as one donor, and incorporation of one atom of oxygen into each donor. The systematic name of this enzyme class is dihydroflavonol,2-oxoglutarate:oxygen oxidoreductase. This enzyme participates in flavonoid biosynthesis.

References

• Wellmann F, Lukacin R, Moriguchi T, Britsch L, Schiltz E, Matern U (2002). "Functional expression and mutational analysis of flavonol synthase from Citrus unshiu". Eur. J. Biochem. 269 (16): 4134–42. doi:10.1046/j.1432-1033.2002.03108.x. PMID 12180990.
• Lukacin R, Wellmann F, Britsch L, Martens S, Matern U (2003). "Flavonol synthase from Citrus unshiu is a bifunctional dioxygenase". Phytochemistry. 62 (3): 287–92. doi:10.1016/S0031-9422(02)00567-8. PMID 12620339.
• Martens S, Forkmann G, Britsch L, Wellmann F, Matern U, Lukacin R (2003). "Divergent evolution of flavonoid 2-oxoglutarate-dependent dioxygenases in parsley". FEBS Lett. 544 (1–3): 93–8. doi:10.1016/S0014-5793(03)00479-4. PMID 12782296.
• CJ; Nakajima, J; Welford, RW; Yamazaki, M; Saito, K; Schofield, CJ (2004). "Mechanistic studies on three 2-oxoglutarate-dependent oxygenases of flavonoid biosynthesis: anthocyanidin synthase, flavonol synthase, and flavanone 3beta-hydroxylase". J. Biol. Chem. 279 (2): 1206–16. doi:10.1074/jbc.M309228200. PMID 14570878.