Regio‐ and Stereospecific Prenylation of Flavonoids by Sophora flavescens Prenyltransferase

Abstract

Prenylflavonoids are valuable natural products that are widely distributed in plants. They often possess divergent biological properties, including phytoestrogenic, anti‐bacterial, anti‐tumor, and anti‐diabetic activities. The reaction catalyzed by prenyltransferases represents a Friedel–Crafts alkylation of the flavonoid skeleton in the biosynthesis of natural prenylflavonoids and often contributes to the structural diversity and biological activity of these compounds. However, only a few plant flavonoid prenyltransferases have been identified thus far, and these prenyltransferases exhibit strict substrate specificity and low catalytic efficiency. In this article, a flavonoid prenyltransferase from Sophora flavescens, SfFPT, has been identified that displays high catalytic efficiency with high regiospecificity acting on C‐8 of structurally different types of flavonoid (i.e., flavanone, flavone, flavanonol, and dihydrochalcone, etc.). Furthermore, SfPFT exhibits strict stereospecificity for levorotatory flavanones to produce (2S)‐prenylflavanones. This study is the first to demonstrate the substrate promiscuity and stereospecificity of a plant flavonoid prenyltransferase in vitro. Given its substrate promiscuity and high catalytic efficiency, SfFPT can be used as an environmentally friendly and efficient biological catalyst for the regio‐ and stereospecific prenylation of flavonoids to produce bioactive compounds for potential therapeutic applications.

Molecular Characterization and Phylogenetic Analysis of Two Novel Regio-specific Flavonoid Prenyltransferases from Morus alba and Cudrania tricuspidata

“…Therefore, we initially hypothesized that the FPTs of M. alba would cluster together with the leguminous FPTs and used degenerated primer pairs based on these FPTs to clone the candidate gene(s). Similar cloning strategies proved to be successful in the isolation of SfFPT and GuA6DT from S. flavescens and Glycyrrhiza uralensis in our previous work (14,15). However, after RT-PCR and RACE, we failed to achieve active PTs.…”

“…The microsomal fractions of YPH499 expressing pESC-HIS-MaIDT and pESC-HIS-CtIDT were prepared as previously described (14,15) and resuspended in 100 mM Tris-HCl (pH 9.0). The total protein concentration was determined by the Bradford method (30).…”

“…tricuspidata-To increase understanding of the diversity of the FPTs in moraceous plants, a cell suspension culture of C. tricuspidata was chosen for further study. Due to the absence of genetic information about C. tricuspidata, homologous PCR was used to clone candidate gene(s) as previously described (14,15). Similarly, degenerated primer pairs based on the conserved regions of the leguminous FPTs failed to produce an active FPT.…”

“…These observations indicated that FPTs existed in the cell suspension cultures of each of the two plants. Therefore, in our ongoing work on plant FPTs (14,15), cell suspension cultures of M. alba and C. tricuspidata were selected as materials from which to isolate non-Leguminosae FPTs.…”

A Stilbenoid-Specific Prenyltransferase Utilizes Dimethylallyl Pyrophosphate from the Plastidic Terpenoid Pathway

“…This enzyme catalyzes the dimethylallylation of glycinol at position 4 to produce the precursor of the phytoalexin, glyceollin I (Akashi et al, 2009). More recently, GuA6DT, a flavone prenyltransferase, was identified in another legume species, liquorice (Glycyrrhiza uralensis; Li et al, 2014), and SfFPT characterized from S. flavescens displays high catalytic efficiency of C-8 prenylation on different types of flavonoids, including flavanone, flavone, and flavanonol (Chen et al, 2013).…”