Document Type
Article
Author ORCID Identifier
Owen M. Price https://orcid.org/0000-0001-5894-9022
Joan Hevel https://orcid.org/0000-0002-9559-4635
Jixun Zhan https://orcid.org/0000-0003-0200-9183
Journal/Book Title
Applied Microbiology and Biotechnology
Publication Date
12-7-2021
Award Number
NSF, Division of Chemical, Bioengineering, Environmental, and Transport Systems (CBET) 2044558
Funder
NSF, Division of Chemical, Bioengineering, Environmental, and Transport Systems (CBET)
Publisher
Springer
Volume
106
Abstract
Glycosylation is an effective way to improve the water solubility of natural products. In this work, a novel glycosyltransferase gene (BbGT) was discovered from Beauveria bassiana ATCC 7159 and heterologously expressed in Escherichia coli. The purified enzyme was functionally characterized through in vitro enzymatic reactions as a UDP-glucosyltransferase, converting quercetin to five monoglucosylated and one diglucosylated products. The optimal pH and temperature for BbGT are 35 ℃ and 8.0, respectively. The activity of BbGT was stimulated by Ca2+, Mg2+, and Mn2+, but inhibited by Zn2+. BbGT enzyme is flexible and can glycosylate a variety of substrates such as curcumin, resveratrol, and zearalenone. The enzyme was also expressed in other microbial hosts including Saccharomyces cerevisiae, Pseudomonas putida, and Pichia pastoris. Interestingly, the major glycosylation product of quercetin in E. coli, P. putida, and P. pastoris was quercetin-7-O-β-D-glucoside, while the enzyme dominantly produced quercetin-3-O-β-D-glucoside in S. cerevisiae. The BbGT-harboring E. coli and S. cerevisiae strains were used as whole-cell biocatalysts to specifically produce the two valuable quercetin glucosides, respectively. The titer of quercetin-7-O-β-D-glucosides was 0.34 ± 0.02 mM from 0.83 mM quercetin in 24 h by BbGT-harboring E. coli. The yield of quercetin-3-O-β-D-glucoside was 0.22 ± 0.02 mM from 0.41 mM quercetin in 12 h by BbGT-harboring S. cerevisiae. This work thus provides an efficient way to produce two valuable quercetin glucosides through the expression of a versatile glucosyltransferase in different hosts.
First Page
227
Last Page
245
Recommended Citation
Ren, J., Tang, W., Barton, C.D. et al. A highly versatile fungal glucosyltransferase for specific production of quercetin-7-O-β-D-glucoside and quercetin-3-O-β-D-glucoside in different hosts. Appl Microbiol Biotechnol 106, 227–245 (2022). https://doi.org/10.1007/s00253-021-11716-x
Comments
This is a post-peer-review, pre-copyedit version of an article published in Applied Microbiology. The final authenticated version is available online at: https://doi.org/10.1007/s00253-021-11716-x