Biosynthesis of ferulic acid 4-O-glucoside and feruloyl glucoside using Escherichia coli harboring regioselective glucosyltransferases

Twelve candidate uridine diphosphate-dependent glucosyltransferases (UGTs) from Arabidopsis thaliana were screened to identify UGTs that synthesized ferulic acid 4- O -glucoside or feruloyl glucoside, respectively. We used biotransformation using E. coli harboring each UGT. E. coli harboring AtUGT71C1 could synthesize feruloyl glucoside with a conversion rate of 1.8 μM/h. E. coli harboring AtUGT72E2 showed the best conversion rate for converting ferulic acid into ferulic acid glucoside, at 15.8 μM/h. Molecular docking analysis of ferulic acid into the modeled structures of AtUGT71C1 and AtUGT72E2 was used to elucidate the different conversion rates of ferulic acid into corresponding glucoside.