Discovery and characterization of tannase genes in plants: roles in hydrolysis of tannins

Abstract

Plant tannins, including condensed tannins (CTs) and hydrolyzable tannins (HTs), are widely distributed in the plant kingdom. To date, tannase (TA)is a type of tannin acyl-hydrolase hydrolyzing HTs, CT monomer gallates and depsideshas been reported in microbes only. Whether plants express TA remains unknown.Herein, we report plant TA genes. A native Camellia sinensis TA (CsTA) is identified from leaves. Six TAs are cloned from tea, strawberry (Fragaria 9 ananassa, Fa) and four other crops. Biochemical analysis shows that the native CsTA and six recombinant TAs hydrolyze tannin compounds, depsides and phenolic glycosides.Transcriptional and metabolic analyses reveal that the expression of CsTA is oppositely associated with the accumulation of galloylated catechins. Moreover, the transient overexpression and RNA interference of FaTA are positively associated with the accumulation of ellagitannins in strawberry fruit. Phylogenetic analysis across different kingdoms shows that 29 plant TA homologs are clustered as a plant-specific TA clade in class I carboxylesterases. Further analysis across the angiosperms reveals that these TA genes are dispersed in tanninrich plants, which share a single phylogenetic origin c. 120 million yr ago.Plant TA is discovered for the first time in the plant kingdom and is shown to be valuable to improve tannin compositions in plants.

Metabolism of Gallic Acid and Its Distributions in Tea (Camellia sinensis) Plants at the Tissue and Subcellular Levels

“…9 ( Figure 2 C). This phenomenon may be ubiquitous in tea plants, as the same tendency was also observed in another tea cultivar [ 18 ].…”

“…Recently, metabolomics has further confirmed that the same phenomena also occurs in tea plants [ 16 , 17 ]. For example, among main aroma compounds responsible for tea quality, the contents of terpene volatiles, such as monoterpenes and sesquiterpenes, change significantly with growing season [ 18 ]. In different seasons, different metabolites accumulate in plants with the potential aim of adapting to variational environments.…”

Genome-Wide Analysis of Serine Carboxypeptidase-Like Acyltransferase Gene Family for Evolution and Characterization of Enzymes Involved in the Biosynthesis of Galloylated Catechins in the Tea Plant (Camellia sinensis)

“…On the other hand, hydrolyzable tannins, including PGG (pentagalloylglucose) and EGCG, can be readily hydrolyzed enzymatically to generate series of galloylated glucose derivatives, such as di-, tri-, tetra-, and mono-galloylglucoses, as well as gallic acid and catechins, respectively, by many organisms, such as plants and microbes (Jana et al, 2014;Dai et al, 2020;Zhao et al, 2020). Indeed, our assay showed that empty vector control displayed significant hydrolysis of PGG (Figure 7).…”

HAK/KUP/KT family potassium transporter genes are involved in potassium deficiency and stress responses in tea plants (Camellia sinensis L.): expression and functional analysis

“…With this method, functional characterization of the “in root” genes could be carried out in vivo in the tea plant [ 56 ]. More recently, a native C. sinensis Tannase gene (CsTA) was identified for the first time in plant kingdom [ 57 ]. The transcriptional and metabolic analyses revealed that the expression of CsTA negatively regulated the accumulation of galloylated catechins [ 57 ].…”

“…More recently, a native C. sinensis Tannase gene (CsTA) was identified for the first time in plant kingdom [ 57 ]. The transcriptional and metabolic analyses revealed that the expression of CsTA negatively regulated the accumulation of galloylated catechins [ 57 ]. Moreover, Dong et al(2020) showed that six amino acid permeases in tea plant exhibited theanine transport activity, and suggested a role for CsAPP1 in transporting theanine from roots toward new shoots [ 58 ].…”