Regiospecific synthesis of prenylated flavonoids by a prenyltransferase cloned from Fusarium oxysporum

Weiliang Rong,Bao Yang,Xiaoman Yang,Hongshun Yang,Jiali Yang,Yueming Jiang,Ze Yun

doi:10.1038/srep24819

Abstract

Due to their impressive pharmaceutical activities and safety, prenylated flavonoids have a high potent to be applied as medicines and nutraceuticals. Biocatalysis is an effective technique to synthesize prenylated flavonoids. The major concern of this technique is that the microbe-derived prenyltransferases usually have poor regiospecificity and generate multiple prenylated products. In this work, a highly regiospecific prenyltransferase (FoPT1) was found from Fusarium oxysporum. It could recognize apigenin, naringenin, genistein, dihydrogenistein, kampferol, luteolin and hesperetin as substrates, and only 6-C-prenylated flavonoids were detected as the products. The catalytic efficiency of FoPT1 on flavonoids was in a decreasing order with hesperetin >naringenin >apigenin >genistein >luteolin >dihydrogenistein >kaempferol. Chalcones, flavanols and stilbenes were not active when acting as the substrates. 5,7-Dihydroxy and 4-carbonyl groups of flavonid were required for the catalysis. 2,3-Alkenyl was beneficial to the catalysis whereas 3-hydroxy impaired the prenylation reaction. Docking studies simulated the prenyl transfer reaction of FoPT1. E186 was involved in the formation of prenyl carbonium ion. E98, F89, F182, Y197 and E246 positioned apigenin for catalysis.

Highlights

Due to their impressive pharmaceutical activities and safety, prenylated flavonoids have a high potent to be applied as medicines and nutraceuticals
Prenylated flavonoids are an important class of phenolics, which combine a flavonoid skeleton with a lipophilic prenyl side chain
In planta, prenylated flavonoids are considered as phytoalexins[5], compounds that play key roles in physiological behaviors when defending against pathogenic microorganisms

Summary

Fusarium oxysporum

Xiaoman Yang1,2,*, Jiali Yang1,2,*, Yueming Jiang[1], Hongshun Yang[3], Ze Yun[1], Weiliang Rong1 & Bao Yang[1]. A highly regiospecific prenyltransferase (FoPT1) was found from Fusarium oxysporum It could recognize apigenin, naringenin, genistein, dihydrogenistein, kampferol, luteolin and hesperetin as substrates, and only 6-C-prenylated flavonoids were detected as the products. Enzyme assays were performed in reaction system vessels (200 μl) containing 50 mM Tris-HCl (pH 7.5), 10 mM divalent cations, 500 μM flavonoid substrates, 1 mM DMAPP and 180 μg of recombinant FoPT1. To prepare the enzymatic products for structure elucidation, the reaction volume was scaled up to 10 mL, containing 50 mM Tris-HCl (pH 7.5), 10 mM CaCl2, 500 μM flavonoid substrates (apigenin, dihydrogenistein, genistein, hesperitin, kaempferol, luteolin and naringenin), 1 mM DMAPP and 9 mg of recombinant FoPT1. Regular molecular dynamics simulation for 12 ns was conducted

Results and Discussion

Conclusions

Author Contributions

Additional Information