scholarly journals Metabolism of methionine and biosynthesis of caffeine in the tea plant (Camellia sinensis L.)

1976 ◽  
Vol 160 (2) ◽  
pp. 171-179 ◽  
Author(s):  
T Suzuki ◽  
E Takahashi
Keyword(s):  
Nucleic Acids ◽  
Gradient Centrifugation ◽  
Tea Plant ◽  
Shoot Tips ◽  
Purine Nucleotides ◽  
Unknown Compound ◽  
Caffeine Biosynthesis ◽  
Tea Shoot ◽  
Tea Plants ◽  
Almost All

1. Caffeine biosynthesis was studied by following the incorporation of 14C into the products of L-[Me-14C]methionine metabolism in tea shoot tips. 2. After administration of a ‘pulse’ of L-[Me-14C]methionine, almost all of the L-[Me-14C]methionine supplied disappeared within 1 h, and 14C-labelled caffeine synthesis increased throughout the experimental periods, whereas the radioactivities of an unknown compound and theobromine were highest at 3 h after the uptake of L-[Me-14C]methionine, followed by a steady decrease. There was also slight incorporation of the label into 7-methylxanthine, serine, glutamate and aspartate, disappearing by 36 h after the absorption of L-[Me-14C]methionine. 3. The radioactivities of nucleic acids derived from L-[Me-14C]methionine increased rapidly during the first 12 h incubation period and then decreased steadily. Sedimentation analysis of nucleic acids by sucrose-gradient centrifugation showed that methylation of nucleic acids in tea shoot tips occurred mainly in the tRNA fraction. The main product among the methylated bases in tea shoot tips was identified as 1-methyladenine. 4. The results indicated that the purine ring in caffeine is derived from the purine nucleotides in the nucleotide pool rather than in nucleic acids. A metabolic scheme to show the production of caffeine and related methylxanthines from the nucleotides in tea plants is discussed.

scholarly journals Metabolism of xanthine and hypoxanthine in the tea plant (Thea sinensis L.)

1975 ◽  
Vol 146 (1) ◽  
pp. 79-85 ◽  
Author(s):  
T Suzuki ◽  
E Takahashi
Keyword(s):  
De Novo ◽  
Tea Plant ◽  
Shoot Tips ◽  
Purine Nucleotides ◽  
Purine Salvage ◽  
Nucleotide Synthesis ◽  
Caffeine Biosynthesis ◽  
Tea Shoot ◽  
Tea Plants ◽  
Almost All

1. The metabolism of xanthine and hypoxanthine in excised shoot tips of tea was studied with micromolar amounts of [2(-14)C]xanthine or [8(-14)C]hypoxanthine. Almost all of the radioactive compounds supplied were utilized by tea shoot tips by 30 h after their uptake. 2. The main products of [2(-14)C]xanthine and [8(-14)C]hypoxanthine metabolism in tea shoots were urea, allantoin and allantoic acid. There was also incorporation of the label into theobromine, caffeine and RNA purine nucleotides. 3. The results indicate that tea plants can catabolize purine bases by the same pathways as animals. It is also suggested that tea plants have the ability to snythesize purine nucleotides from glycine by the pathways of purine biosynthesis de novo and from hypoxanthine and xanthine by the pathway of purine salvage. 4. The results of incorporation of more radioactivity from [8(-14)C]hypoxanthine than from [2(-14)C]xanthine into RNA purine nucleotides and caffeine suggest that hypoxanthine is a more effective precursor of caffeine biosynthesis than xanthine. The formation of caffeine from hypoxanthine is a result of nucleotide synthesis via the pathway of purine salvage.

scholarly journals Metabolism of methylamine in the tea plant (Thea sinensis L.)

1973 ◽  
Vol 132 (4) ◽  
pp. 753-763 ◽  
Author(s):  
Takeo Suzuki
Keyword(s):  
Experimental Period ◽  
Tea Plant ◽  
Shoot Tips ◽  
Purine Nucleotides ◽  
Period 2 ◽  
Tea Plants

1. The metabolism of methylamine in excised shoot tips of tea was studied with micromolar amounts of [14C]methylamine. Of the [14C]methylamine supplied 57% was utilized by tea shoots during the 10h experimental period. 2. The main products of [14C]methylamine metabolism in tea shoots were serine, γ-glutamylmethylamide, theobromine, caffeine and CO2. There was also incorporation of the label into glutamate, aspartate, RNA purine nucleotides and S-adenosylmethionine. 3. The formation of methylamine from γ-glutamylmethylamide was confirmed by feeding tea shoots with γ-glutamyl[14C]methylamide. The products of γ-glutamyl[14C]methylamide metabolism in tea plants were serine, theobromine, caffeine, glutamate and aspartate. 4. The results indicate that the oxidation of methylamine to formaldehyde is the first step of methylamine utilization. Labelled formaldehyde released by the metabolism of methylamine leads to the incorporation of the label into metabolites on the C1 pathways of this compound. It is also suggested that formaldehyde is further oxidized via formate to CO2. 5. The role of γ-glutamylmethylamide in methylamine metabolism in tea plants is discussed. 6. Results support the view that theobromine is the immediate precursor of caffeine.

scholarly journals Further investigation of the biosynthesis of caffeine in tea plants (Camellia sinensis L.). Methylation of transfer ribonucleic acid by tea leaf extracts

1976 ◽  
Vol 160 (2) ◽  
pp. 181-184 ◽  
Author(s):  
T Suzuki ◽  
E Takahashi
Keyword(s):  
Nucleic Acids ◽  
Ammonium Acetate ◽  
Tea Leaves ◽  
Leaf Extracts ◽  
Thiol Compounds ◽  
Caffeine Biosynthesis ◽  
Trna Methyltransferase ◽  
Tea Plants ◽  
Tea Leaf

1. The tRNA methyltransferase activity in vitro of leaves, cotyledons and roots of 85-day-old tea seedlings was studied. 2. The activity of extracts prepared from tea leaves with Polycar AT (insoluble polyvinylpyrrolidine) had optimum pH7.7 and was greatly influenced by thiol compounds, but only slightly by metal ions and ammonium acetate. 3. The activities of extracts, expressed per mg of protein, were as follows: roots greater than leaves greater than cotyledons. The only methylated base isolated after incubation with these preparations was 1-methyladenine. 4. The results did not support the view of involvement of methylation of nucleic acids in caffeine biosynthesis in tea plants. In contrast, it is suggested that theophylline is synthesized from the specific methylated precursor in nucleic acids, namely 1-methyladenylic acid, via 1-methylxanthine.

scholarly journals Metabolic Changes of Amino Acids and Flavonoids in Tea Plants in Response to Inorganic Phosphate Limitation

2018 ◽  
Vol 19 (11) ◽  
pp. 3683 ◽  
Author(s):  
Santosh KC ◽  
Meiya Liu ◽  
Qunfeng Zhang ◽  
Kai Fan ◽  
Yuanzhi Shi ◽  
...  
Keyword(s):  
Amino Acids ◽  
Inorganic Phosphate ◽  
Tea Plant ◽  
Phosphate Limitation ◽  
P Limitation ◽  
Metabolic Genes ◽  
Expression Of Genes ◽  
Tea Plants ◽  
Change Response ◽  
Tof Ms

The qualities of tea (Camellia sinensis) are not clearly understood in terms of integrated leading molecular regulatory network mechanisms behind inorganic phosphate (Pi) limitation. Thus, the present work aims to elucidate transcription factor-dependent responses of quality-related metabolites and the expression of genes to phosphate (P) starvation. The tea plant organs were subjected to metabolomics analysis by GC×GC-TOF/MS and UPLC-Q-TOF/MS along with transcription factors and 13 metabolic genes by qRT-PCR. We found P starvation upregulated SPX2 and the change response of Pi is highly dependent on young shoots. This led to increased change in abundance of carbohydrates (fructose and glucose), amino acids in leaves (threonine and methionine), and root (phenylalanine, alanine, tryptophan, and tyrosine). Flavonoids and their glycosides accumulated in leaves and root exposed to P limitation was consistent with the upregulated expression of anthocyanidin reductase (EC 1.3.1.77), leucoanthocyanidin dioxygenase (EC 1.4.11.19) and glycosyltransferases (UGT78D1, UGT78D2 and UGT57L12). Despite the similar kinetics and high correlation response of Pi and SPX2 in young shoots, predominating theanine and other amino acids (serine, threonine, glutamate, valine, methionine, phenylalanine) and catechin (EGC, EGCG and CG) content displayed opposite changes in response to Pi limitation between Fengqing and Longjing-43 tea cultivars.

scholarly journals Molecular Identification and Characterization of Hydroxycinnamoyl Transferase in Tea Plants (Camellia sinensis L.)

2018 ◽  
Vol 19 (12) ◽  
pp. 3938 ◽  
Author(s):  
Chi-Hui Sun ◽  
Chin-Ying Yang ◽  
Jason Tzen
Keyword(s):  
Abiotic Stress ◽  
Amino Acid ◽  
Camellia Sinensis ◽  
Polymerase Chain Reaction Analysis ◽  
Coffea Canephora ◽  
Tea Plant ◽  
Amino Acid Sequences ◽  
Hibiscus Cannabinus ◽  
Expression Level ◽  
Tea Plants

Tea (Camellia sinensis L.) contains abundant secondary metabolites, which are regulated by numerous enzymes. Hydroxycinnamoyl transferase (HCT) is involved in the biosynthesis pathways of polyphenols and flavonoids, and it can catalyze the transfer of hydroxyconnamoyl coenzyme A to substrates such as quinate, flavanol glycoside, or anthocyanins, thus resulting in the production of chlorogenic acid or acylated flavonol glycoside. In this study, the CsHCT gene was cloned from the Chin-Shin Oolong tea plant, and its protein functions and characteristics were analyzed. The full-length cDNA of CsHCT contains 1311 base pairs and encodes 436 amino acid sequences. Amino acid sequence was highly conserved with other HCTs from Arabidopsis thaliana, Populus trichocarpa, Hibiscus cannabinus, and Coffea canephora. Quantitative real-time polymerase chain reaction analysis showed that CsHCT is highly expressed in the stem tissues of both tea plants and seedlings. The CsHCT expression level was relatively high at high altitudes. The abiotic stress experiment suggested that low temperature, drought, and high salinity induced CsHCT transcription. Furthermore, the results of hormone treatments indicated that abscisic acid (ABA) induced a considerable increase in the CsHCT expression level. This may be attributed to CsHCT involvement in abiotic stress and ABA signaling pathways.

scholarly journals Effect of Inorganic and Organic Liquid Fertilizer Application with Different Application Frequency on Growth of Yielding Tea

2021 ◽  
pp. 83-90
Author(s):  
Faris Nur Fauzi Athallah ◽  
Restu Wulansari ◽  
Eko Pranoto ◽  
Muhammad Alimin
Keyword(s):  
Tap Water ◽  
Organic Liquid ◽  
Block Design ◽  
Organic Fertilizer ◽  
Tea Plant ◽  
Organic Fertilizers ◽  
Liquid Form ◽  
Liquid Fertilizer ◽  
Tea Plants ◽  
Inorganic And Organic

Input factor is one of the determinator the quality and response of the tea plant growth. Inorganic fertilizer input still dominates in Indonesian plantations due to the lack of comprehensive evaluation of organic fertilizers, especially in liquid form. This study aims to determine the effect of inorganic and organic liquid fertilizer applications and the frequency of their application on the growth of tea plants. The experiment was carried out based on a Randomized Block Design (RBD) consisting of six treatment combinations, including tap water application once a week, tap water once every two weeks, 1% urea once a week, 1% urea every two weeks, 1% POC once a week and 1% POC once every two weeks. Experiments were carried out on yielding tea plants with the 3rd year of pruning stage. The parameters observed were shoot production (kg/plot), weight of banji and pekoe (g/100g) and the ratio of banji/pekoe. The results showed that the application of urea foliar fertilizer and liquid organic fertilizer with different application frequencies did not have a significant effect on each observed parameter. Application of 1% liquid organic fertilizer once every two weeks has the potential to increase tea productivity by showing a relatively high production of tea (6,88 kg/plot) compared to other treatments.

scholarly journals Functional Analyses of Flavonol Synthase Genes From Camellia sinensis Reveal Their Roles in Anther Development

2021 ◽  
Vol 12 ◽  
Author(s):  
Yufeng Shi ◽  
Xiaolan Jiang ◽  
Linbo Chen ◽  
Wei-Wei Li ◽  
Sanyan Lai ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Developmental Stages ◽  
Expression Patterns ◽  
Reproductive Organs ◽  
Tea Plant ◽  
Functional Verification ◽  
Metabolic Characteristics ◽  
Metabolic Properties ◽  
Tea Plants ◽  
Functional Analyses

Flavonoids, including flavonol derivatives, are the main astringent compounds of tea and are beneficial to human health. Many researches have been conducted to comprehensively identify and characterize the phenolic compounds in the tea plant. However, the biological function of tea flavonoids is not yet understood, especially those accumulated in floral organs. In this study, the metabolic characteristics of phenolic compounds in different developmental stages of flower buds and various parts of the tea flower were investigated by using metabolomic and transcriptomic analyses. Targeted metabolomic analysis revealed varying accumulation patterns of different phenolic polyphenol compounds during flowering; moreover, the content of flavonol compounds gradually increased as the flowers opened. Petals and stamens were the main sites of flavone and flavonol accumulation. Compared with those of fertile flowers, the content of certain flavonols, such as kaempferol derivatives, in anthers of hybrid sterile flowers was significantly low. Transcriptomic analysis revealed different expression patterns of genes in the same gene family in tea flowers. The CsFLSb gene was significantly increased during flowering and was highly expressed in anthers. Compared with fertile flowers, CsFLSb was significantly downregulated in sterile flowers. Further functional verification of the three CsFLS genes indicated that CsFLSb caused an increase in flavonol content in transgenic tobacco flowers and that CsFLSa acted in leaves. Taken together, this study highlighted the metabolic properties of phenolic compounds in tea flowers and determined how the three CsFLS genes have different functions in the vegetative and reproductive organs of tea plants. Furthermore, CsFLSb could regulated flavonol biosynthesis in tea flowers, thus influencing fertility. This research is of great significance for balancing the reproductive growth and vegetative growth of tea plants.

scholarly journals Effects of Exogenous 6-Benzyladenine on Dwarfing, Shoot Branching, and Yield of Tea Plant (Camellia sinensis)

HortScience ◽  
2018 ◽  
Vol 53 (5) ◽  
pp. 651-655 ◽  
Author(s):  
Liping Zhang ◽  
Chen Shen ◽  
Jipeng Wei ◽  
Wenyan Han
Keyword(s):  
Plant Height ◽  
Camellia Sinensis ◽  
Photosynthetic Rate ◽  
Tea Plant ◽  
Shoot Branching ◽  
Tea Plants ◽  
Lateral Branches ◽  
Spring Yield

6-Benzyladenine (6-BA) is a safe and efficient cytokinin. The adult tea plants of the cv. Longjing 43 were used in this study. The foliar portion of tea bushes were sprayed with different concentrations (50, 100, 200, or 400 mg·L−1) of 6-BA after heavy pruning, when three to four leaves grew out in late May. The effects of 6-BA application on the growth of the new shoots and lateral branches were quantified. After 5 months, treatments with 50, 100, 200, or 400 mg·L−1 6-BA suppressed plant height by 11.0%, 18.0%, 21.0%, or 22.0%, respectively; 6-BA at 100, 200, or 400 mg·L−1 decreased the number of lateral branches by 20.0%, 23.0%, or 18.0%, respectively. Meanwhile, treatments with 50, 200, or 400 mg·L−1 6-BA increased the length of lateral branches by 38.0%, 79.0%, or 81.0% respectively; 200 mg·L−1 6-BA increased the diameter of lateral branches by 8.0%. In addition, after 2 months, 50 or 200 mg·L−1 6-BA did not significantly affect the growth of functional leaves, 50, 100, or 200 mg·L−1 6-BA did not significantly affect photosynthetic rate (Pn) as compared with the control. Furthermore, 200 or 400 mg·L−1 6-BA significantly increased spring tea yield by 28.9% or 13.3%, respectively as compared with the control. In conclusion, 6-BA at the four concentrations promoted dwarfing and the formation of productive lateral branches and increased the spring yield, and 200 mg·L−1 6-BA exerted the best comprehensive effect.

scholarly journals Low Caffeine Content in Novel Grafted Tea with Camellia sinensis as Scions and Camellia oleifera as Stocks

2015 ◽  
Vol 10 (5) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Wei-Wei Deng ◽  
Min Li ◽  
Chen-Chen Gu ◽  
Da-Xiang Li ◽  
Lin-Long Ma ◽  
...  
Keyword(s):  
Camellia Sinensis ◽  
Expression Patterns ◽  
Tea Plant ◽  
Protein Accumulation ◽  
Tea Leaves ◽  
Qrt Pcr ◽  
Caffeine Content ◽  
Caffeine Synthase ◽  
Specificity And Sensitivity ◽  
Tea Plants

Caffeine, a purine alkaloid, is a major secondary metabolite in tea leaves. The demand for low caffeine tea is increasing in recent years, especially for health reasons. We report a novel grafted tea material with low caffeine content. The grafted tea plant had Camellia sinensis as scions and C. oleifera as stocks. The content of purine alkaloids was determined in the leaves of one-year-old grafted tea plants by HPLC. We also characterized caffeine synthase (CS), a key enzyme involved in caffeine biosynthesis in tea plants, at the expression level. The expression patterns of CS were examined in grafted and control leaves by Western blot, using a self-prepared polyclonal antibody with high specificity and sensitivity. The expression of related genes ( TCS1, tea caffeine synthase gene, GenBank accession No. AB031280; sAMS, SAM synthetase gene, AJ277206; TIDH, IMP dehydrogenase gene, EU106658) in the caffeine biosynthetic pathway was investigated by qRT-PCR. HPLC showed that the caffeine content was only 38% as compared with the non-grafted tea leaves. Immunoblotting analysis showed that CS protein decreased by half in the leaves of grafted tea plants. qRT-PCR revealed no significant changes in the expression of two genes in the upstream pathway ( sAMS and TIDH), while the expression of TCS1 was greatly decreased (50%). Taken together, these data revealed that the low caffeine content in the grafted tea leaves is due to low TCS1 expression and CS protein accumulation.

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