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Chen Y, Han Y, Tong H. Amino acids and flavonoids analysis reveals quality constituents difference among different albino tea resources. Food Chem 2024; 449:139200. [PMID: 38574523 DOI: 10.1016/j.foodchem.2024.139200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 03/24/2024] [Accepted: 03/29/2024] [Indexed: 04/06/2024]
Abstract
Albino tea has attracted increased attention due to its unique flavor. To reveal the difference in key metabolites constituting the important quality of different tea resources, amino acids and flavonoids profiles in three albino resources with different degrees of albinism and one normal green variety were comprehensively investigated. K-means analysis revealed 35 amino acids were significantly enriched in 'Jibai', while 3 and 2 were specifically accumulated in 'Huangjinya' and 'Anjibaicha', respectively. Based on OPLS-DA models, 40, 31 and 45 significantly differential flavonoids were determined in 'Huangjinya', 'Anjibaicha' and 'Jibai' compared to 'Fudingdabaicha', and most were down-regulated. Among them, 10, 5 and 13 differential flavonoids were exclusively found in 'Huangjinya', 'Anjibaicha' and 'Jibai', respectively, which may contribute to unique quality for different resources. The differential flavonoids and amino acids involved in their metabolic pathways were obviously different among four resources, resulting in the difference in tea quality and flavor.
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Affiliation(s)
- Yingjuan Chen
- Department of Tea Science, College of Food Science, Southwest University, Chongqing 400715, China.
| | - Yuxin Han
- Department of Tea Science, College of Food Science, Southwest University, Chongqing 400715, China
| | - Huarong Tong
- Department of Tea Science, College of Food Science, Southwest University, Chongqing 400715, China
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Fan YG, Zhao TT, Xiang QZ, Han XY, Yang SS, Zhang LX, Ren LJ. Multi-Omics Research Accelerates the Clarification of the Formation Mechanism and the Influence of Leaf Color Variation in Tea ( Camellia sinensis) Plants. PLANTS (BASEL, SWITZERLAND) 2024; 13:426. [PMID: 38337959 PMCID: PMC10857240 DOI: 10.3390/plants13030426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/24/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024]
Abstract
Tea is a popular beverage with characteristic functional and flavor qualities, known to be rich in bioactive metabolites such as tea polyphenols and theanine. Recently, tea varieties with variations in leaf color have been widely used in agriculture production due to their potential advantages in terms of tea quality. Numerous studies have used genome, transcriptome, metabolome, proteome, and lipidome methods to uncover the causes of leaf color variations and investigate their impacts on the accumulation of crucial bioactive metabolites in tea plants. Through a comprehensive review of various omics investigations, we note that decreased expression levels of critical genes in the biosynthesis of chlorophyll and carotenoids, activated chlorophyll degradation, and an impaired photosynthetic chain function are related to the chlorina phenotype in tea plants. For purple-leaf tea, increased expression levels of late biosynthetic genes in the flavonoid synthesis pathway and anthocyanin transport genes are the major and common causes of purple coloration. We have also summarized the influence of leaf color variation on amino acid, polyphenol, and lipid contents and put forward possible causes of these metabolic changes. Finally, this review further proposes the research demands in this field in the future.
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Affiliation(s)
- Yan-Gen Fan
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271018, China; (Y.-G.F.); (T.-T.Z.); (Q.-Z.X.); (X.-Y.H.)
| | - Ting-Ting Zhao
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271018, China; (Y.-G.F.); (T.-T.Z.); (Q.-Z.X.); (X.-Y.H.)
| | - Qin-Zeng Xiang
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271018, China; (Y.-G.F.); (T.-T.Z.); (Q.-Z.X.); (X.-Y.H.)
| | - Xiao-Yang Han
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271018, China; (Y.-G.F.); (T.-T.Z.); (Q.-Z.X.); (X.-Y.H.)
| | - Shu-Sen Yang
- Yipinming Tea Planting Farmers Specialized Cooperative, Longnan 746400, China;
| | - Li-Xia Zhang
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271018, China; (Y.-G.F.); (T.-T.Z.); (Q.-Z.X.); (X.-Y.H.)
| | - Li-Jun Ren
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271018, China; (Y.-G.F.); (T.-T.Z.); (Q.-Z.X.); (X.-Y.H.)
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Huang R, Wang Z, Wen W, Yao M, Liu H, Li F, Zhang S, Ni D, Chen L. Comprehensive dissection of variation and accumulation of free amino acids in tea accessions. HORTICULTURE RESEARCH 2024; 11:uhad263. [PMID: 38304331 PMCID: PMC10833077 DOI: 10.1093/hr/uhad263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 11/26/2023] [Indexed: 02/03/2024]
Abstract
Free amino acids (FAAs) positively determine the tea quality, notably theanine (Thea), endowing umami taste of tea infusion, which is the profoundly prevalent research in albino tea genetic resources. Therefore, 339 tea accessions were collected to study FAAs level for deciphering its variation and accumulation mechanism. Interestingly, alanine (Ala) and Thea which had the highest diversity index (H') value among three varieties of Camellia sinensis (L.) O. Kuntze were significantly higher than wild relatives (P < 0.05). The intraspecific arginine (Arg) and glutamine (Gln) contents in C. sinensis var. assamica were significantly lower than sinensis and pubilimba varieties. Moreover, the importance of interdependencies operating across FAAs and chlorophyll levels were highlighted via the cell ultrastructure, metabolomics, and transcriptome analysis. We then determined that the association between phytochrome interacting factor 1 (CsPIF1) identified by weighted gene co-expression network analysis (WGCNA) and Thea content. Intriguingly, transient knock-down CsPIF1 expression increased Thea content in tea plant, and the function verification of CsPIF1 in Arabidopsis also indicated that CsPIF1 acts as a negative regulator of Thea content by mainly effecting the genes expression related to Thea biosynthesis, transport, and hydrolysis, especially glutamate synthase (CsGOGAT), which was validated to be associated with Thea content with a nonsynonymous SNP by Kompetitive Allele-Specific PCR (KASP). We also investigated the interspecific and geographical distribution of this SNP. Taken together, these results help us to understand and clarify the variation and profile of major FAAs in tea germplasms and promote efficient utilization in tea genetic improvement and breeding.
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Affiliation(s)
- Rong Huang
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhihua Wang
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Weiwei Wen
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Mingzhe Yao
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Haoran Liu
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Fang Li
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Shuran Zhang
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
| | - Dejiang Ni
- College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Liang Chen
- Key Laboratory of Biology, Genetics and Breeding of Special Economic Animals and Plants, Ministry of Agriculture and Rural Affairs; Tea Research Institute of the Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
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Li H, Song K, Zhang X, Wang D, Dong S, Liu Y, Yang L. Application of Multi-Perspectives in Tea Breeding and the Main Directions. Int J Mol Sci 2023; 24:12643. [PMID: 37628823 PMCID: PMC10454712 DOI: 10.3390/ijms241612643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/29/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
Tea plants are an economically important crop and conducting research on tea breeding contributes to enhancing the yield and quality of tea leaves as well as breeding traits that satisfy the requirements of the public. This study reviews the current status of tea plants germplasm resources and their utilization, which has provided genetic material for the application of multi-omics, including genomics and transcriptomics in breeding. Various molecular markers for breeding were designed based on multi-omics, and available approaches in the direction of high yield, quality and resistance in tea plants breeding are proposed. Additionally, future breeding of tea plants based on single-cellomics, pangenomics, plant-microbe interactions and epigenetics are proposed and provided as references. This study aims to provide inspiration and guidance for advancing the development of genetic breeding in tea plants, as well as providing implications for breeding research in other crops.
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Affiliation(s)
| | | | | | | | | | | | - Long Yang
- College of Plant Protection and Agricultural Big-Data Research Center, Shandong Agricultural University, Tai’an 271018, China
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Chang M, Ma J, Sun Y, Tian L, Liu L, Chen Q, Zhang Z, Wan X, Sun J. γ-Glutamyl-transpeptidase CsGGT2 functions as light-activated theanine hydrolase in tea plant (Camellia sinensis L.). PLANT, CELL & ENVIRONMENT 2023; 46:1596-1609. [PMID: 36757089 DOI: 10.1111/pce.14561] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 01/31/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
Theanine is an important secondary metabolite endowing tea with umami taste and health effects. It is essential to explore the metabolic pathway and regulatory mechanism of theanine to improve tea quality. Here, we demonstrated that the expression patterns of CsGGT2 (γ-glutamyl-transpeptidase), participated in theanine synthesis in vitro in our previous research, are significantly different in the aboveground and underground tissues of tea plants and regulated by light. Light up-regulated the expression of CsHY5, directly binding to the promoter of CsGGT2 and acting as an activator of CsGGT2, with a negative correlation with theanine accumulation. The enzyme activity assays and transient expression in Nicotiana benthamiana showed that CsGGT2, acting as bifunctional protein, synthesize and degrade theanine in vitro and in planta. The results of enzyme kinetics, Surface plasmon resonance (SPR) assays and targeted gene-silencing assays showed that CsGGT2 had a higher substrate affinity of theanine than that of ethylamine, and performed a higher theanine degradation catalytic efficiency. Therefore, light mediates the degradation of theanine in different tissues by regulating the expression of the theanine hydrolase CsGGT2 in tea plants, and these results provide new insights into the degradation of theanine mediated by light in tea plants.
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Affiliation(s)
- Manman Chang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Jingyu Ma
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Ying Sun
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Liying Tian
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Linlin Liu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Qi Chen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Zhaoliang Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
| | - Jun Sun
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
- College of Horticulture, Anhui Agricultural University, Hefei City, Anhui Province, People's Republic of China
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Chang M, Ma J, Sun Y, Fu M, Liu L, Chen Q, Zhang Z, Song C, Sun J, Wan X. Role of Endophytic Bacteria in the Remobilization of Leaf Nitrogen Mediated by CsEGGT in Tea Plants ( Camellia sinensis L.). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5208-5218. [PMID: 36970979 DOI: 10.1021/acs.jafc.2c08909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
As an important economic plant, tea (Camellia sinensis) has a good economic value and significant health effects. Theanine is an important nitrogen reservoir, and its synthesis and degradation are considered important for nitrogen storage and remobilization in tea plants. Our previous research indicated that the endophyte CsE7 participates in the synthesis of theanine in tea plants. Here, the tracking test confirmed that CsE7 tended to be exposed to mild light and preferentially colonized mature tea leaves. CsE7 also participated in glutamine, theanine, and glutamic acid circulatory metabolism (Gln-Thea-Glu) and contributed to nitrogen remobilization, mediated by the γ-glutamyl-transpeptidase (CsEGGT) with hydrolase preference. The reisolation and inoculation of endophytes further verified their role in accelerating the remobilization of nitrogen, especially in the reuse of theanine and glutamine. This is the first report about the photoregulated endophytic colonization and the positive effect of endophytes on tea plants mediated and characterized by promoting leaf nitrogen remobilization.
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Affiliation(s)
- Manman Chang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Jingyu Ma
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Ying Sun
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Maoyin Fu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Linlin Liu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Qi Chen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Zhaoliang Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Chuankui Song
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Jun Sun
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
- College of Horticulture, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei City, Anhui Province 230036, P. R. China
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Chen Z, Lin S, Chen T, Han M, Yang T, Wang Y, Bao S, Shen Z, Wan X, Zhang Z. Haem Oxygenase 1 is a potential target for creating etiolated/albino tea plants ( Camellia sinensis) with high theanine accumulation. HORTICULTURE RESEARCH 2023; 10:uhac269. [PMID: 37533676 PMCID: PMC10390853 DOI: 10.1093/hr/uhac269] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/01/2022] [Indexed: 08/04/2023]
Abstract
Theanine content is highly correlated with sensory quality and health benefits of tea infusion. The tender shoots of etiolated and albino tea plants contain higher theanine than the normal green tea plants and are valuable materials for high quality green tea processing. However, why these etiolated or albino tea plants can highly accumulate theanine is largely unknown. In this study, we observed an Arabidopsis etiolated mutant hy1-100 (mutation in Haem Oxygenase 1, HO1) that accumulated higher levels of glutamine (an analog of theanine). We therefore identified CsHO1 in tea plants and found CsHO1 is conserved in amino acid sequences and subcellular localization with its homologs in other plants. Importantly, CsHO1 expression in the new shoots was much lower in an etiolated tea plants 'Huangkui' and an albino tea plant 'Huangshan Baicha' than that in normal green tea plants. The expression levels of CsHO1 were negatively correlated with theanine contents in these green, etiolated and albino shoots. Moreover, CsHO1 expression levels in various organs and different time points were also negatively correlated with theanine accumulation. The hy1-100 was hypersensitive to high levels of theanine and accumulated more theanine under theanine feeding, and these phenotypes were rescued by the expression of CsHO1 in this mutant. Transient knockdown CsHO1 expression in the new shoots of tea plant using antisense oligonucleotides (asODN) increased theanine accumulation. Collectively, these results demonstrated CsHO1 negatively regulates theanine accumulation in tea plants, and that low expression CsHO1 likely contributes to the theanine accumulation in etiolated/albino tea plants.
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Affiliation(s)
| | | | - Tingting Chen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Mengxue Han
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Tianyuan Yang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Yan Wang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Shilai Bao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
- School of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhougao Shen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
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Yang J, Zhou H, Liu Y, Wang H, Xu Y, Huang J, Lei P. Chemical constituents of green teas processed from albino tea cultivars with white and yellow shoots. FOOD CHEMISTRY: MOLECULAR SCIENCES 2022; 5:100143. [PMID: 36389341 PMCID: PMC9640954 DOI: 10.1016/j.fochms.2022.100143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/21/2022] [Accepted: 10/29/2022] [Indexed: 11/06/2022]
Abstract
Green teas produced from white (NB) and yellow (HJY) shoots have distinct flavor. Concentrations of non-galloylated catechins and amino acids are high in NB teas. HJY green teas contain high concentration of galloylated catechins. CsTA and CsPDX2.1 (involved in catabolism) are highly expressed in HJY tea shoots. Total concentration of volatile compounds is higher in HJY than in NB green teas.
Green tea processed from albino tea varieties often has umami taste and fresh aroma. This study identified green teas made from two types of albino tea cultivar, one having the white shoots (called Naibai, NB) and the other having the yellow shoots (called Huangjinya, HJY). Taste compounds analyses showed that galloylated catechins were highly concentrated in HJY green teas, whereas non-galloylated catechins and amino acids were more abundant in NB green teas. CsTA (involved in the catabolism of galloylated catechins) showed high expression in HJY tea shoots, resulting in gallic acid as a precursor for β-glucogallin biosynthesis being abundant in HJY. CsPDX2.1 (responsible for theanine hydrolyzation) had a lower expression level in NB than HJY shoots. Fatty acid–derived volatiles (FADVs), glycosidically bound volatiles (GBVs) and carotenoid–derived volatiles (CDVs) were highly concentrated in HJY green teas, whereas amino acids–derived volatiles were highly concentrated in NB green teas.
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Chen T, Ma J, Li H, Lin S, Dong C, Xie Y, Yan X, Zhang S, Yang T, Wan X, Zhang Z. CsGDH2.1 negatively regulates theanine accumulation in late-spring tea plants ( Camellia sinensis var. sinensis). HORTICULTURE RESEARCH 2022; 10:uhac245. [PMID: 36643747 PMCID: PMC9832843 DOI: 10.1093/hr/uhac245] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 10/23/2022] [Indexed: 06/17/2023]
Abstract
Theanine, a unique and the most abundant non-proteinogenic amino acid in tea plants, endows tea infusion with the umami taste and anti-stress effects. Its content in tea correlates highly with green tea quality. Theanine content in new shoots of tea plants is high in mid-spring and greatly decreases in late spring. However, how the decrease is regulated is largely unknown. In a genetic screening, we observed that a yeast mutant, glutamate dehydrolase 2 (gdh2), was hypersensitive to 40 mM theanine and accumulated more theanine. This result implied a role of CsGDH2s in theanine accumulation in tea plants. Therefore, we identified the two homologs of GDH2, CsGDH2.1 and CsGDH2.2, in tea plants. Yeast complementation assay showed that the expression of CsGDH2.1 in yeast gdh2 mutant rescued the theanine hypersensitivity and hyperaccumulation of this mutant. Subcellular localization and tissue-specific expression showed CsGDH2.1 localized in the mitochondria and highly expressed in young tissues. Importantly, CsGDH2.1 expression was low in early spring, and increased significantly in late spring, in the new shoots of tea plants. These results all support the idea that CsGDH2.1 regulates theanine accumulation in the new shoots. Moreover, the in vitro enzyme assay showed that CsGDH2.1 had glutamate catabolic activity, and knockdown of CsGDH2.1 expression increased glutamate and theanine accumulation in the new shoots of tea plants. These findings suggested that CsGDH2.1-mediated glutamate catabolism negatively regulates theanine accumulation in the new shoots in late spring, and provides a functional gene for improving late-spring green tea quality.
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Affiliation(s)
| | | | | | - Shijia Lin
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Chunxia Dong
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Yunxia Xie
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Xiaomei Yan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Shupei Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Tianyuan Yang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
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Li J, Xiao Y, Zhou X, Liao Y, Wu S, Chen J, Qian J, Yan Y, Tang J, Zeng L. Characterizing the cultivar-specific mechanisms underlying the accumulation of quality-related metabolites in specific Chinese tea (Camellia sinensis) germplasms to diversify tea products. Food Res Int 2022; 161:111824. [DOI: 10.1016/j.foodres.2022.111824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 08/03/2022] [Accepted: 08/19/2022] [Indexed: 12/25/2022]
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Xu YX, Yang L, Lei YS, Ju RN, Miao SG, Jin SH. Integrated transcriptome and amino acid profile analyses reveal novel insights into differential accumulation of theanine in green and yellow tea cultivars. TREE PHYSIOLOGY 2022; 42:1501-1516. [PMID: 35146518 DOI: 10.1093/treephys/tpac016] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 02/04/2022] [Indexed: 06/14/2023]
Abstract
Tea cultivars with yellow- or white-leaf variations have a high economic value due to their high amino acid (especially theanine) concentration. However, the dynamic changes of amino acid components (especially theanine) and related gene expression during new shoot development in these cultivars are still unclear. In this study, 264 tea samples from four representative varieties picked during the harvest period in spring were analyzed for their amino acid profiles. The dynamic change rules of ethylamine and 19 amino acids were summarized in normal green and yellow cultivars during new shoot development. Interestingly, the theanine concentration in the yellow cultivar was significantly higher than that in the green cultivar, and increased gradually as the leaves matured until they reached a maximum in the one bud and three leaves stage. The amino acid concentration in the leaves of the yellow cultivar increased significantly with leaf position, which was generally in contrast to the normal green cultivar. Transcriptome and correlation analyses revealed that CsGS1, CsPDX2, CsGGP5, CsHEMA3 and CsCLH4 might be the key genes potentially responsible for the differential accumulation of theanine in green and yellow tea cultivars. These results provide further information for the utilization and improvement of tea plants.
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Affiliation(s)
- Yan-Xia Xu
- Jiyang College, Zhejiang A&F University, 66 Puyang Road, Zhuji, Zhejiang 311800, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A &F University, 666 Wusu Street, Lin'an, Zhejiang 311300, China
| | - Long Yang
- Jiyang College, Zhejiang A&F University, 66 Puyang Road, Zhuji, Zhejiang 311800, China
| | - Yun-Sheng Lei
- Jiyang College, Zhejiang A&F University, 66 Puyang Road, Zhuji, Zhejiang 311800, China
| | - Rui-Na Ju
- Jiyang College, Zhejiang A&F University, 66 Puyang Road, Zhuji, Zhejiang 311800, China
| | - Shu-Gang Miao
- Jiyang College, Zhejiang A&F University, 66 Puyang Road, Zhuji, Zhejiang 311800, China
| | - Song-Heng Jin
- Jiyang College, Zhejiang A&F University, 66 Puyang Road, Zhuji, Zhejiang 311800, China
- The Nurturing Station for the State Key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, 666 Wusu Street, Lin'an, Zhejiang 311300, China
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Zhou B, Chen Y, Zeng L, Cui Y, Li J, Tang H, Liu J, Tang J. Soil nutrient deficiency decreases the postharvest quality-related metabolite contents of tea (Camellia sinensis (L.) Kuntze) leaves. Food Chem 2022; 377:132003. [PMID: 35008025 DOI: 10.1016/j.foodchem.2021.132003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 11/10/2021] [Accepted: 11/27/2021] [Indexed: 11/04/2022]
Abstract
The long-term cultivation of tea plants without fertilization can severely decrease yield, but it remains unclear whether this soil nutrient deficiency affects tea quality. In this study, tea plants (Camellia sinensis (L.) Kuntze) cultivated in unfertilized soil for 11 years were analyzed. The soil nutrient deficiency down-regulated protochlorophyllide oxidoreductase-encoding gene expression, which adversely affected chlorophyll biosynthesis, ultimately leading to leaf etiolation. Because of decreased synthesis and increased degradation in response to nutrient deficiency, l-theanine content decreased to 11.4% of the control level, which increased the phenol-ammonia ratio and decreased taste quality. Soil nutrient deficiency also decreased the abundance of many aroma compounds (e.g., green leaf volatile, linalool and its oxides, and methyl salicylate). Thus, nutrient deficiency adversely influences tea color, taste, and aroma. This study provides researchers and tea growers with important information regarding the effects of soil nutrient deficiency on tea quality and the rational fertilization of tea gardens.
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Affiliation(s)
- Bo Zhou
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China
| | - Yiyong Chen
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China
| | - Lanting Zeng
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
| | - Yingying Cui
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China
| | - Jianlong Li
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China
| | - Hao Tang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China
| | - Jiayu Liu
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China
| | - Jinchi Tang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, No. 6 Dafeng Road, Tianhe District, Guangzhou 510640, China.
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13
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Lin S, Chen Z, Chen T, Deng W, Wan X, Zhang Z. Theanine metabolism and transport in tea plants ( Camellia sinensis L.): advances and perspectives. Crit Rev Biotechnol 2022; 43:327-341. [PMID: 35430936 DOI: 10.1080/07388551.2022.2036692] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Theanine, a tea plant-specific non-proteinogenic amino acid, is the most abundant free amino acid in tea leaves. It is also one of the most important quality components of tea because it endows the "umami" taste, relaxation-promoting, and many other health benefits of tea infusion. Its content in tea leaves is directly correlated with the quality and price of green tea. Theanine biosynthesis primarily occurs in roots and is transported to new shoots in tea plants. Recently, great advances have been made in theanine metabolism and transport in tea plants. Along with the deciphering of the genomic sequences of tea plants, new genes in theanine metabolic pathway were discovered and functionally characterized. Theanine transporters were identified and were characterized on the affinity for: theanine, substrate specificity, spatiotemporal expression, and the role in theanine root-to-shoot transport. The mechanisms underlying the regulation of theanine accumulation by: cultivars, seasons, nutrients, and environmental factors are also being rapidly uncovered. Transcription factors were identified to be critical regulators of theanine biosynthesis. In this review, we summarize the progresses in theanine: biosynthesis, catabolism, and transport processes. We also discuss the future studies on theanine in tea plants, and application of the knowledge to crops to synthesize theanine to improve the health-promoting quality of non-tea crops.
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Affiliation(s)
- Shijia Lin
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, PR China
| | - Ziping Chen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, PR China
| | - Tingting Chen
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, PR China
| | - Weiwei Deng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, PR China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, PR China
| | - Zhaoliang Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, PR China
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14
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Cheng H, Wu W, Liu X, Wang Y, Xu P. Transcription factor CsWRKY40 regulates L-theanine hydrolysis by activating the CsPDX2.1 promoter in tea leaves during withering. HORTICULTURE RESEARCH 2022; 9:uhac025. [PMID: 35184176 PMCID: PMC9055099 DOI: 10.1093/hr/uhac025] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/17/2022] [Accepted: 01/26/2022] [Indexed: 05/11/2023]
Abstract
L-Theanine is a crucial secondary metabolite in tea and positively determines the potential quality and health benefits of tea products. Previous work found the content of L-theanine decreased during withering process, while the specific mechanism is still unknown. Here, weighted gene co-expression network analysis (WGCNA) was performed based on the transcriptome data obtained previously. The key hydrolysis gene CsPDX2.1 in L-theanine metabolism and seven candidate transcription factors were screened out. Among those transcription factors, CsWRKY40 presented the strongest activation on the CsPDX2.1 promoter (373.18-fold) by binding to W box element based on the dual luciferase assay and EMSA results. Meanwhile, CsWRKY40 protein was located in the nucleoplasm, while CsPDX2.1 was found in both the nucleoplasm and cytoplasm. Furthermore, it was confirmed that the water loss of tea leaves was the critical factor affecting the contents of ABA and L-theanine by activating the expression of CsPDX2.1 and CsPDX2.1 based on the analysis of the withering model, water-retention model and water-loss model. Our results provide a new insight into revealing the regulation mechanism of L-theanine hydrolysis metabolism.
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Affiliation(s)
- Haiyan Cheng
- Institute of Tea Science, Zhejiang University, Hangzhou 310058, Zhejiang, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, Zhejiang, China
| | - Wei Wu
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Xiaofen Liu
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Yuefei Wang
- Institute of Tea Science, Zhejiang University, Hangzhou 310058, Zhejiang, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, Zhejiang, China
| | - Ping Xu
- Institute of Tea Science, Zhejiang University, Hangzhou 310058, Zhejiang, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, Zhejiang, China
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15
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Yu P, Huang H, Zhao X, Zhong N, Zheng H. Dynamic variation of amino acid content during black tea processing: A review. FOOD REVIEWS INTERNATIONAL 2022. [DOI: 10.1080/87559129.2021.2015374] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Penghui Yu
- Tea Research Institute, Hunan Academy of Agricultural Sciences, Changsha, China
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, China
- National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, China
| | - Hao Huang
- Tea Research Institute, Hunan Academy of Agricultural Sciences, Changsha, China
| | - Xi Zhao
- Tea Research Institute, Hunan Academy of Agricultural Sciences, Changsha, China
| | - Ni Zhong
- Tea Research Institute, Hunan Academy of Agricultural Sciences, Changsha, China
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, China
- National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, Hunan Agricultural University, Changsha, China
| | - Hongfa Zheng
- Tea Research Institute, Hunan Academy of Agricultural Sciences, Changsha, China
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16
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Fu X, Liao Y, Cheng S, Deng R, Yang Z. Stable Isotope-Labeled Precursor Tracing Reveals that l-Alanine is Converted to l-Theanine via l-Glutamate not Ethylamine in Tea Plants In Vivo. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:15354-15361. [PMID: 34904439 DOI: 10.1021/acs.jafc.1c06660] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Tea plants (Camellia sinensis) specifically produce l-theanine, which contributes to tea function and taste. Ethylamine is a limiting factor differentiating l-theanine accumulation between tea and other plants. Ethylamine has long been assumed to be derived from l-alanine in tea. In this study, the l-alanine content in tea root cells was mainly located in vacuoles and mitochondria using a nonaqueous fractionation technique, while alanine decarboxylase in tea (CsADC) was located in the cytoplasm. Although CsADC was able to catalyze l-alanine decarboxylation to produce ethylamine in vitro, it may not provide the same enzyme activity in tea plants. Stable isotope-labeled precursor tracing in tea plants discovered that l-alanine is not a direct precursor of ethylamine but a precursor of l-glutamate, which is involved in l-theanine biosynthesis in tea. Cortex with epidermis from root tissue was the main location of ethylamine. In summary, l-alanine is converted to l-theanine via l-glutamate not ethylamine in tea plants in vivo.
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Affiliation(s)
- Xiumin Fu
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
| | - Yinyin Liao
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
| | - Sihua Cheng
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
| | - Rufang Deng
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
| | - Ziyin Yang
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China
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17
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Yu Y, Kou X, Gao R, Chen X, Zhao Z, Mei H, Li J, Jeyaraj A, Thangaraj K, Periakaruppan R, Zhuang J, Chen X, Arkorful E, Li X. Glutamine Synthetases Play a Vital Role in High Accumulation of Theanine in Tender Shoots of Albino Tea Germplasm "Huabai 1". JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:13904-13915. [PMID: 34775761 DOI: 10.1021/acs.jafc.1c04567] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Theanine (N-ethyl-γ-l-glutamine) is a special nonprotein amino acid that contributes to the umami taste and health function of tea. Although recent studies on tea breeding have focused on albino tea because of its umami taste, a factor of higher theanine concentration, the mechanism of biosynthesis of l-theanine is still unclear. In this study, four glutamine synthetase genes (CsGSs) were obtained and functionally characterized by overexpressing them in Arabidopsis. The enzyme activities of the purified CsGS proteins from Escherichia coli were detected. The results showed that CsGSs have a dual function in the synthesis of glutamine and theanine in vivo and in vitro. Interestingly, l-theanine was abundantly synthesized in the tender shoots of "Huabai 1". In the white tender shoots, the cytosol CsGS1.2 might exhibit increased expression to compensate for decreasing levels of chloroplast CsGS2, which plays a vital role in high accumulation of theanine in "Huabai 1". In addition, CsGS2 was most likely the key l-theanine synthases in green tissues of tea. The present findings will provide basis for and considerably broaden the scope of understanding the function of CsGSs and the mechanism of l-theanine accumulation in the tender shoots of "Huabai 1", and will be useful for breeding and screening tea with high l-theanine content.
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Affiliation(s)
- Ying Yu
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Xiaobing Kou
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Ruoshi Gao
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Xuefei Chen
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Zhen Zhao
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Huiling Mei
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jianjie Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Anburaj Jeyaraj
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Kuberan Thangaraj
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Rajiv Periakaruppan
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Jing Zhuang
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Xuan Chen
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
| | - Emmanuel Arkorful
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Nara 630-0192, Japan
| | - Xinghui Li
- College of Horticulture, Nanjing Agricultural University, Weigang No.1, Nanjing 210095, China
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18
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19
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Production of l-Theanine by Escherichia coli in the Absence of Supplemental Ethylamine. Appl Environ Microbiol 2021; 87:AEM.00031-21. [PMID: 33741612 DOI: 10.1128/aem.00031-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/09/2021] [Indexed: 11/20/2022] Open
Abstract
l-Theanine is a nonproteinogenic amino acid present almost exclusively in tea plants and is beneficial for human health. For industrial production, l-theanine is enzymatically or chemically synthesized from glutamine/glutamate (or a glutamine/glutamate derivative) and ethylamine. Ethylamine is extremely flammable and toxic, which complicates and increases the cost of operational procedures. To solve these problems, we developed an artificial biosynthetic pathway to produce l-theanine in the absence of supplemental ethylamine. For this purpose, we identified and selected a novel transaminase (NCBI:protein accession number AAN70747) from Pseudomonas putida KT2440, which catalyzes the transamination of acetaldehyde to produce ethylamine, as well as γ-glutamylmethylamide synthetase (NCBI:protein accession number AAY37316) from Pseudomonas syringae pv. syringae B728a, which catalyzes the condensation of l-glutamate and ethylamine to produce l-theanine. Expressing these genes in Escherichia coli W3110S3GK and enhancing the production capacity of acetaldehyde and l-alanine achieved successful production of l-theanine without ethylamine supplementation. Furthermore, the deletion of ggt, which encodes γ-glutamyltranspeptidase (EC 2.3.2.2), achieved large-scale production of l-theanine by attenuating its decomposition. We show that an alanine decarboxylase-utilizing pathway represents a promising route for the fermentative production of l-theanine. Our study reports efficient methods to produce l-theanine in the absence of supplemental ethylamine.IMPORTANCE l-Theanine is widely used in food additives and dietary supplements. Industrial production of l-theanine uses the toxic and highly flammable precursor ethylamine, raising production costs. In this study, we used Escherichia coli to engineer two biosynthetic pathways that produce l-theanine from glucose and ammonia in the absence of supplemental ethylamine. This study establishes a foundation for safely and economically producing l-theanine.
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20
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Chen Y, Wang F, Wu Z, Jiang F, Yu W, Yang J, Chen J, Jian G, You Z, Zeng L. Effects of Long-Term Nitrogen Fertilization on the Formation of Metabolites Related to Tea Quality in Subtropical China. Metabolites 2021; 11:metabo11030146. [PMID: 33801425 PMCID: PMC8000315 DOI: 10.3390/metabo11030146] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/25/2021] [Accepted: 02/25/2021] [Indexed: 12/31/2022] Open
Abstract
As a main agronomic intervention in tea cultivation, nitrogen (N) application is useful to improve tea yield and quality. However, the effects of N application on the formation of tea quality-related metabolites have not been fully studied, especially in long-term field trials. In this study, a 10-year field experiment was conducted to investigate the effect of long-term N application treatments on tea quality-related metabolites, their precursors, and related gene expression. Long-term N application up-regulated the expression of key genes for chlorophyll synthesis and promoted its synthesis, thus increasing tea yield. It also significantly increased the contents of total free amino acids, especially l-theanine, in fresh tea leaves, while decreasing the catechin content, which is conducive to enhancing tea liquor freshness. However, long-term N application significantly reduced the contents of benzyl alcohol and 2-phenylethanol in fresh tea leaves, and also reduced (E)-nerolidol and indole in withered leaves, which were not conducive to the formation of floral and fruity aroma compounds. In general, an appropriate amount of N fertilizer (225 kg/hm2) balanced tea yield and quality. These results not only provide essential information on how N application affects tea quality, but also provide detailed experimental data for field fertilization.
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Affiliation(s)
- Yuzhen Chen
- Tea Research Institute, Fujian Academy of Agricultural Sciences, No. 104 Pudang Road, Xindian Town, Jin’an District, Fuzhou 350012, China; (Y.C.); (F.W.); (Z.W.); (F.J.)
- National Agricultural Experimental Station for Soil Quality, No. 1 Hutouyang Road, Shekou Town, Fu’an 355015, China
| | - Feng Wang
- Tea Research Institute, Fujian Academy of Agricultural Sciences, No. 104 Pudang Road, Xindian Town, Jin’an District, Fuzhou 350012, China; (Y.C.); (F.W.); (Z.W.); (F.J.)
- National Agricultural Experimental Station for Soil Quality, No. 1 Hutouyang Road, Shekou Town, Fu’an 355015, China
| | - Zhidan Wu
- Tea Research Institute, Fujian Academy of Agricultural Sciences, No. 104 Pudang Road, Xindian Town, Jin’an District, Fuzhou 350012, China; (Y.C.); (F.W.); (Z.W.); (F.J.)
- National Agricultural Experimental Station for Soil Quality, No. 1 Hutouyang Road, Shekou Town, Fu’an 355015, China
| | - Fuying Jiang
- Tea Research Institute, Fujian Academy of Agricultural Sciences, No. 104 Pudang Road, Xindian Town, Jin’an District, Fuzhou 350012, China; (Y.C.); (F.W.); (Z.W.); (F.J.)
- National Agricultural Experimental Station for Soil Quality, No. 1 Hutouyang Road, Shekou Town, Fu’an 355015, China
| | - Wenquan Yu
- Fujian Academy of Agricultural Sciences, No. 247 Wusi Road, Gulou District, Fuzhou 350013, China;
| | - Jie Yang
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China; (J.Y.); (J.C.); (G.J.)
| | - Jiaming Chen
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China; (J.Y.); (J.C.); (G.J.)
| | - Guotai Jian
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China; (J.Y.); (J.C.); (G.J.)
| | - Zhiming You
- Tea Research Institute, Fujian Academy of Agricultural Sciences, No. 104 Pudang Road, Xindian Town, Jin’an District, Fuzhou 350012, China; (Y.C.); (F.W.); (Z.W.); (F.J.)
- National Agricultural Experimental Station for Soil Quality, No. 1 Hutouyang Road, Shekou Town, Fu’an 355015, China
- Correspondence: (Z.Y.); (L.Z.)
| | - Lanting Zeng
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China; (J.Y.); (J.C.); (G.J.)
- Correspondence: (Z.Y.); (L.Z.)
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21
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Liao Y, Zhou X, Zeng L. How does tea ( Camellia sinensis) produce specialized metabolites which determine its unique quality and function: a review. Crit Rev Food Sci Nutr 2021; 62:3751-3767. [PMID: 33401945 DOI: 10.1080/10408398.2020.1868970] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Tea (Camellia sinensis) is both a plant and a foodstuff. Many bioactive compounds, which are present in the final tea product and related to its quality or functional properties, are produced during the tea manufacturing process. However, the characteristic secondary metabolites, which give tea its unique qualities and are beneficial to human health, are produced mainly in the leaves during the process of plant growth. Therefore, it is important to understand how tea leaves produce these specialized metabolites. In this review, we first compare the common metabolites and specialized metabolites in tea, coffee, cocoa, and grape and discuss the occurrence of characteristic secondary metabolites in tea. Progress in research into the formation of these characteristic secondary metabolites in tea is summarized, including establishing a biological database and genetic transformation system, and the biosynthesis of characteristic secondary metabolites. Finally, speculation on future research into the characteristic secondary metabolites of tea is provided from the viewpoints of the origin, resources, cultivation, and processing of tea. This review provides an important reference for future research on the specialized metabolites of tea in terms of its characteristics.
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Affiliation(s)
- Yinyin Liao
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaochen Zhou
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Lanting Zeng
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.,Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou, China
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22
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Liao Y, Fu X, Zeng L, Yang Z. Strategies for studying in vivo biochemical formation pathways and multilevel distributions of quality or function-related specialized metabolites in tea (Camellia sinensis). Crit Rev Food Sci Nutr 2020; 62:429-442. [DOI: 10.1080/10408398.2020.1819195] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Yinyin Liao
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiumin Fu
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Lanting Zeng
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou, China
| | - Ziyin Yang
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou, China
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