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7. Efficient Production of Flavonoid Glucuronides in Escherichia coliUsing Flavonoid O-Glucuronosyltransferases Characterized from Marchantia polymorpha

Author

Du, Ni-Hong, Xiong, Rui-Lin, Zhu, Ting-Ting, Liu, Xin-Yan, Zhang, Jiao-Zhen, Fu, Jie, Wang, Hai-Long, Lou, Hong-Xiang, and Cheng, Ai-Xia

Abstract

As a model liverwort, Marchantia polymorphacontains various flavone glucuronides with cardiovascular-promoting effects and anti-inflammatory properties. However, the related glucuronosyltransferases have not yet been reported. In this study, two bifunctional UDP-glucuronic acid/UDP-glucose:flavonoid glucuronosyltransferases/glucosyltransferases, MpUGT742A1 and MpUGT736B1, were identified from M. polymorpha. Extensive enzymatic assays found that MpUGT742A1 and MpUGT736B1 exhibited efficient glucuronidation activity for flavones, flavonols, and flavanones and showed promiscuous regioselectivity at positions 3, 6, 7, 3′, and 4′. These enzymes catalyzed the production of a variety of flavonoid glucuronides with medicinal value, including apigenin-7-O-glucuronide and scutellarein-7-O-glucuronide. With the use of MpUGT736B1, apigenin-4′-O-glucuronide and apigenin-7,4′-di-O-glucuronide were prepared by scaled-up enzymatic catalysis and structurally identified by NMR spectroscopy. MpUGT742A1 also displayed glucosyltransferase activity on the 7-OH position of the flavanones using UDP-glucose as the sugar donor. Furthermore, we constructed four recombinant strains by combining the pathway for increasing the UDP-glucuronic acid supply with the two novel UGTs MpUGT742A1 and MpUGT736B1. When apigenin was used as a substrate, the extracellular apigenin-4′-O-glucuronide and apigenin-7,4′-di-O-glucuronide production obtained from the Escherichia colistrain BB2 reached 598 and 81 mg/L, respectively. Our study provides new candidate genes and strategies for the biosynthesis of flavonoid glucuronides.

Published
2024
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15. Additional file 1 of Identification of a flavonoid C-glycosyltransferase from fern species Stenoloma chusanum and the application in synthesizing flavonoid C-glycosides in Escherichia coli

Author

Ni, Rong, Liu, Xin-Yan, Zhang, Jiao-Zhen, Fu, Jie, Tan, Hui, Zhu, Ting-Ting, Zhang, Jing, Wang, Hai-Long, Lou, Hong-Xiang, and Cheng, Ai-Xia

Abstract

Additional file 1: Fig. S1. The possible biosynthetic pathways for C-glycosylflavones. F2H: flavanone 2-hydroxylase; FNS: flavone synthase; CGT: C-glycosyltransferase. Fig. S2. SDS-PAGE analysis of recombinant proteins. M: Weight marker, Lane 1: pET32a, Lane 2: ScGT1, Lane 3: ScGT2, Lane 4: ScGT3, Lane 5: ScGT4, Lane 6: ScCGT1-H26A, Lane 7: ScCGT1-L143T, Lane 8: ScCGT1-P164T, Lane 9: ScCGT1-L301G, Lane 10: ScCGT1-D141I/P142D, Lane 11: ScCGT1-4T (S108D/H109P/V110F/L111F). Fig. S3. Sugar donor selectivity of ScCGT1. A. HPLC chromatograms of the glycosylation reactions using UDP-galactose as sugar donor. B. Typical negative ion MS and MS2 spectra of product 1b. C. HPLC chromatograms of the glycosylation reactions using UDP-glucuronic acid as sugar donor. D. Structures of the sugar donors. E. Relative activity of glycosylated products (1a and 1b) using three sugar donors. Phloretin was used as the acceptor substrate (1, phloretin; Gal, UDP-galactose; GlcA, UDP-glucuronic acid; Glc, UDP-glucose; MS:mass spectrometry; MS2: tandem mass spectrometry). Fig. S4. Sequence alignment of ScCGT1 with CGTs from other plants. The UGTs’ signature PSPG motifs were enclosed in a red box. The abbreviations for species and accession numbers are listed in Additional file 2: Table S2. Fig. S5. Enzymatic characteristics of purified recombinant ScCGT1. Effect of various pH (A) and temperature (B) on the enzyme activities of ScCGT1 using phloretin as substrates, UDP-glucose as sugar donor. Fig. S6. Kinetic analysis of ScCGT1 and ScCGT1-P164T mutant. (1, phloretin; 2, 2-hydroxynaringenin; Glc, UDP-glucose). Fig. S7. The effect of varying the concentration of naringenin on the production of vitexin (2b) and isovitexin (2c). Fig. S8. Subcellular localization of ScCGT1. Sub-cellular localization of vector pGWB5 and the products of the transgenes ScCGT1-GFP in transiently transformed tobacco leaf discs. The GFP signal appears green and the chlorophyll signal is red.

Published
2022
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16. Additional file 2 of Identification of a flavonoid C-glycosyltransferase from fern species Stenoloma chusanum and the application in synthesizing flavonoid C-glycosides in Escherichia coli

Author

Ni, Rong, Liu, Xin-Yan, Zhang, Jiao-Zhen, Fu, Jie, Tan, Hui, Zhu, Ting-Ting, Zhang, Jing, Wang, Hai-Long, Lou, Hong-Xiang, and Cheng, Ai-Xia

Abstract

Additional file 2: Table S1. The sequences of UGT genes in S. chusanum. Table S2. Accession numbers of amino acid sequences used for glycosyltransferases phylogenetic reconstruction. Table S3. The conversion rate generated by the phloretin or naringenin to produce the corresponding C-glycosides at the 100 μM substrate concentration. Table S4. The kinetic parameters of recombinant ScCGT1 and other CGTs using phloretin (1) or 2-hydroxynaringenin (2) as substrate and UDP-glucose as the sugar donor. Table S5. The primers were used for qRT-PCR analysis. Table S6. The primers were used to obtain the full length of ScGTs genes. Table S7. Sequences of specific primers for PCR. Table S8. The primers were used for the site-directed mutagenesis vector construction. Table S9. The primers used for plasmid constructions (into pETDuet-1 vector). Table S10. Primers for sub-cellular localization analysis.

Published
2022
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17. Interaction of PKR with STCS1: an indispensable step in the biosynthesis of lunularic acid in Marchantia polymorpha.

Author

Zhu, Ting‐Ting, Sun, Chun‐Jing, Liu, Xin‐Yan, Zhang, Jiao‐Zhen, Hou, Xu‐Ben, Ni, Rong, Zhang, Jing, Cheng, Ai‐Xia, and Lou, Hong‐Xiang

Subjects
CHALCONE synthase, BIOSYNTHESIS, RING formation (Chemistry), NICOTIANA benthamiana, PROTEIN-protein interactions, VASCULAR plants, PHLORETIN
Abstract

Summary: Unlike bibenzyls derived from the vascular plants, lunularic acid (LA), a key precursor for macrocyclic bisbibenzyl synthesis in nonvascular liverworts, exhibits the absence of one hydroxy group within the A ring. It was hypothesized that both polyketide reductase (PKR) and stilbenecarboxylate synthase 1 (STCS1) were involved in the LA biosynthesis, but the underlined mechanisms have not been clarified.This study used bioinformatics analysis with molecular, biochemical and physiological approaches to characterize STCS1s and PKRs involved in the biosynthesis of LA.The results indicated that MpSTCS1s from Marchantia polymorpha catalyzed both C2→C7 aldol‐type and C6→C1 Claisen‐type cyclization using dihydro‐p‐coumaroyl‐coenzyme A (CoA) and malonyl‐CoA as substrates to yield a C6‐C2‐C6 skeleton of dihydro‐resveratrol following decarboxylation and the C6‐C3‐C6 type of phloretin in vitro. The protein–protein interaction of PKRs with STCS1 (PPI‐PS) was revealed and proved essential for LA accumulation when transiently co‐expressed in Nicotiana benthamiana. Moreover, replacement of the active domain of STCS1 with an 18‐amino‐acid fragment from the chalcone synthase led to the PPI‐PS greatly decreasing and diminishing the formation of LA. The replacement also increased the chalcone formation in STCS1s.Our results highlight a previously unrecognized PPI in planta that is indispensable for the formation of LA. See also the Commentary on this article by Davies & Andre, 237: 371–373. [ABSTRACT FROM AUTHOR]

Published
2023
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29. MOESM4 of Functional characterization of a liverworts bHLH transcription factor involved in the regulation of bisbibenzyls and flavonoids biosynthesis

Author

Zhao, Yu, Zhang, Yu-Ying, Liu, Hui, Xiao-Shuang Zhang, Ni, Rong, Piao-Yi Wang, Shuai Gao, Lou, Hong-Xiang, and Cheng, Ai-Xia

Abstract

Additional file 4: Figure S2. HPLC profiles of bibenzyls from PabHLH1 transgenic P. appendiculatum thallus (D) and the corresponding standards (A-C). (A) The internal standard is baicalein; (B) LA, Lunularic acid and RC, Riccardin C; (C) RD, Riccardin D. UV spectra of (E) LA, (G) RC, and (I) RD standard; UV spectra of the bibenzyls extracted from PabHLH1 transgenic line, LA (F), RC (H) and RD (J).

Published
2019
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33. Identification and evolutionary analysis of chalcone isomerase-fold proteins in ferns.

Author

Ni, Rong, Zhu, Ting-Ting, Zhang, Xiao-Shuang, Wang, Piao-Yi, Sun, Chun-Jing, Qiao, Ya-Nan, Lou, Hong-Xiang, and Cheng, Ai-Xia

Subjects
ISOMERASES, PROTEINS, FERNS, SEQUENCE alignment, BIOSYNTHESIS, CHALCONE synthase
Abstract

The distribution of type I and II chalcone isomerases (CHIs) in plants is highly family specific. We have previously reported that ancient land plants, such as the liverworts and Selaginella moellendorffii , harbor type II CHIs. To better understand the function and evolution of CHI-fold proteins, transcriptomic data obtained from 52 pteridophyte species were subjected to sequence alignment and phylogenetic analysis. The residues determining type I/II CHI identity in the pteridophyte CHIs were identical to those of type I CHIs. The enzymatic characterization of a sample of 24 CHIs, representing all the key pteridophyte lineages, demonstrated that 19 of them were type I enzymes and that five exhibited some type II activity due to an amino acid mutation. Two pteridophyte chalcone synthases (CHSs) were also characterized, and a type IV CHI (CHIL) was demonstrated to interact physically with CHSs and CHI, and to increase CHS activity by decreasing derailment products, thus enhancing flavonoid production. These findings suggest that the emergence of type I CHIs may have coincided with the divergence of the pteridophytes. This study deepens our understanding of the molecular mechanism of CHIL as an enhancer in the flavonoid biosynthesis pathway. [ABSTRACT FROM AUTHOR]

Published
2020
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41. Epoxidation of styrene catalyzed by manganese (III) porphyrins supported on chloromethylated polystyrene resin bearing crown ether groups

Author

You Jing‐Song, Cheng Ai‐Xia, Lan Zhong‐Wei, Yu Xiaoqi, and Xiao You‐Fa

Subjects
inorganic chemicals, chemistry.chemical_classification, Kinetics, chemistry.chemical_element, General Chemistry, Manganese, Porphyrin, Catalysis, Styrene, chemistry.chemical_compound, chemistry, Sodium hypochlorite, Polymer chemistry, Organic chemistry, heterocyclic compounds, Polystyrene, Crown ether
Abstract

Metalloporphyrins and crown ether groups were simultaneously supported on chloromethylated polystyrene resin to produce a series of polymer-supported catalysts. The synthesis of these catalysts has been studied. The influence of pH, concentrations of NaOCl and phase transfer catalysts on the epoxidation of styrene catalyzed by these catalysts has also been investigated. The experimental results show that manganese(III) porphyrin bound to chloromethylated polystyrene which bears crown ether groups is effective catalysts for the epoxidation of styrene by sodium hypochlorite. The introduction of crown ether groups increases the catalytic efficiency of supported metalloporphyrins. The kinetics of epoxidation catalyzed by supported manganese(III) porphyrins obeys Michaelis-Menten equation—the characteristic of enzyme-driven reaction.

Published
2010

47. Identification of chalcone isomerase in the basal land plants reveals an ancient evolution of enzymatic cyclization activity for synthesis of flavonoids.

Author

Cheng, Ai‐Xia, Zhang, Xuebin, Han, Xiao‐Juan, Zhang, Yu‐Ying, Gao, Shuai, Liu, Chang‐Jun, and Lou, Hong‐Xiang

Subjects
*FLAVONOIDS, *CHALCONES, *RING formation (Chemistry), *VASCULAR plants, *ARABIDOPSIS, *BRYOPHYTES
Abstract

* Flavonoids ubiquitously distribute to the terrestrial plants and chalcone isomerase (CHI)-catalyzed intramolecular and stereospecific cyclization of chalcones is a committed step in the production of flavonoids. However, so far the bona fide CHIs are found only in vascular plants, and their origin and evolution remains elusive. * We conducted transcriptomic and/or genomic sequence search, subsequent phylogenetic analysis, and detailed biochemical and genetic characterization to explore the potential existence of CHI proteins in the basal bryophyte liverwort species and the lycophyte Selaginella moellendorffii. * We found that both liverwort and Selaginella species possess canonical CHI-fold proteins that cluster with their corresponding higher plant counterparts. Among them, some members exhibited bona fide CHI activity, which catalyze stereospecific cyclization of both 6'-hydroxychalcone and 6'-deoxychalcone, yielding corresponding 5-hydroxy and 5-deoxyflavanones, resembling the typical type II CHIs currently known to be 'specific' for legume plants. Expressing those primitive bona fide CHIs in the Arabidopsis chi mutant restores the seed coat transparent testa phenotype and the accumulation of flavonoids. * These findings, in contrast to our current understanding of the evolution of enzymatic CHIs, suggest that emergence of the bona fide type II CHIs is an ancient evolution event that occurred before the divergence of liverwort lineages. [ABSTRACT FROM AUTHOR]

Published
2018
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