Ultrasound enhanced biosynthesis of L-theanine from L-glutamine and ethylamine by recombinant γ-glutamyltranspeptidase

Xu, Lisheng; Han, Fangkai; Zhang, Xingtao; Yu, Qiaoling

doi:10.1016/j.biortech.2020.123251

Cited by 11 publications

(19 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…42 Recently, several mutant GGTs were utilized to enhance the L-theanine production. 49,70 Besides, Xu et al 70 found that ultrasound increased the Ltheanine production by 2.61 times. As discussed above, there are a number of advantages in using GGT for producing L-theanine, including higher conversion rate, shorter reaction time, and no requirement for ATP.…”

Section: Methods For L-theanine Productionmentioning

confidence: 99%

See 1 more Smart Citation

From Tea Leaves to Factories: A Review of Research Progress in l-Theanine Biosynthesis and Production

Chen

Wang

Yuan

et al. 2021

J. Agric. Food Chem.

View full text Add to dashboard Cite

l-Theanine is the most popular nonprotein amino acid contained in tea leaves. It is one of the umami components of green tea, contributing to the unique flavor of tea. Because of its various health functions, l-theanine has been commercially developed as a valuable ingredient easily used for various applications in food and pharmaceutical industries. Nowadays, l-theanine is mass-produced by plant extraction, chemical synthesis, or enzymatic transformation in factories. This review embodies the available up to date information on the l-theanine synthesis metabolism in the tea plant as well as approaches to produce it, placing emphasis on the biotransformation of l-theanine. It also gives insight into the challenges of l-theanine production on a large scale, as well as directions for future research. This review comprehensively summarizes information on l-theanine to provide an approach for an in-depth study of l-theanine production.

show abstract

Section: Methods For L-theanine Productionmentioning

confidence: 99%

“…coli GGT of the SUMO fusion system, 41 g/L of l -theanine was produced from 0.267 M l -glutamine and 2 M ethylamine after 24 h reaction . Recently, several mutant GGTs were utilized to enhance the l -theanine production. , Besides, Xu et al found that ultrasound increased the l -theanine production by 2.61 times.…”

Section: Methods For L-theanine Productionmentioning

confidence: 99%

From Tea Leaves to Factories: A Review of Research Progress in l-Theanine Biosynthesis and Production

Chen

Wang

Yuan

et al. 2021

J. Agric. Food Chem.

View full text Add to dashboard Cite

show abstract

“…This synthetic scheme resulted in the generation of relatively low as well as "benign" waste (mostly water), being also characterized by a small C-footprint, as highlighted by complete E-factor and E + -factor. It is worth noting that the latter metrics is far below the values calculated for the enzymatic route by Xu et al [26] and the fully chemical route. [16] On the other hand, this enzymatic synthesis of l-Th occurs in water at room temperature without the need for any additives but the reactants (l-glutamine and ethylamine) at the spontaneous pH (11.6), resulting in very high yield (93 %) and purity (99 %).…”

Section: Discussionmentioning

confidence: 58%

“…Although reaction engineering has been widely applied to date, most of the studies with isolated (immobilized) enzymes were carried out without product isolation, as recently reviewed by Liu et al [24] . On the other hand, in recent years, protein engineering has been also exploited to maximize the transpeptidation activity, while suppressing the enzyme side‐activities (i. e., donor hydrolysis and autotranspeptidation, poly‐glutamylation) [25–27] …”

Section: Introductionmentioning

confidence: 99%

l‐Theanine Goes Greener: A Highly Efficient Bioprocess Catalyzed by the Immobilized γ‐Glutamyl Transferase from Bacillus subtilis

et al. 2023

View full text Add to dashboard Cite

l-Theanine (l-Th) was synthesized by simply mixing the reactants (l-glutamine and ethylamine in water) at 25 °C and Bacillus subtilis γ-glutamyl transferase (BsGGT) covalently immobilized on glyoxyl-agarose according to a methodology previously reported by our research group; neither buffers, nor other additives were needed. Ratio of l-glutamine (donor) to ethylamine (acceptor), pH, enzymatic units (IU), and reaction time were optimized (molar ratio of donor/acceptor = 1 : 8, pH 11.6, 1 IU mL À 1 , 6 h), furnishing l-Th in 93 % isolated yield (485 mg, 32.3 g L À 1 ) and high purity (99 %), after a simple filtration of the immobilized biocatalyst, distillation of the volatiles (unreacted ethylamine) and direct lyophilization. Immobilized BsGGT was re-used (four reaction cycles) with 100 % activity retention. This enzymatic synthesis represents a straightforward, fast, high-yielding, and easily scalable approach to l-Th preparation, besides having a favorable green chemistry metrics.

show abstract

“…Addition of fixed amounts of glutamine and ethylamine after constant intervals resulted in a final yield of 53.5 g/L with a conversion rate of 63% after 16 h (Yang T. et al, 2019). Recently, the use of ultrasound power of 100 W has been reported to increase theanine yield by 2.61-fold using E. coli K-12 GGT with a conversion rate of 89.1% (Xu et al, 2020). Interestingly, in a recent report by Sun et al (2019), endophytic bacteria present in Camellia sinensis has been shown to contribute toward the production of L-theanine.…”

Section: L-theaninementioning

confidence: 99%

Bacterial Gamma-Glutamyl Transpeptidase, an Emerging Biocatalyst: Insights Into Structure–Function Relationship and Its Biotechnological Applications

et al. 2021

View full text Add to dashboard Cite

Gamma-glutamyl transpeptidase (GGT) enzyme is ubiquitously present in all life forms and plays a variety of roles in diverse organisms. Higher eukaryotes mainly utilize GGT for glutathione degradation, and mammalian GGTs have implications in many physiological disorders also. GGTs from unicellular prokaryotes serve different physiological functions in Gram-positive and Gram-negative bacteria. In the present review, the physiological significance of bacterial GGTs has been discussed categorizing GGTs from Gram-negative bacteria like Escherichia coli as glutathione degraders and from pathogenic species like Helicobacter pylori as virulence factors. Gram-positive bacilli, however, are considered separately as poly-γ-glutamic acid (PGA) degraders. The structure–function relationship of the GGT is also discussed mainly focusing on the crystallization of bacterial GGTs along with functional characterization of conserved regions by site-directed mutagenesis that unravels molecular aspects of autoprocessing and catalysis. Only a few crystal structures have been deciphered so far. Further, different reports on heterologous expression of bacterial GGTs in E. coli and Bacillus subtilis as hosts have been presented in a table pointing toward the lack of fermentation studies for large-scale production. Physicochemical properties of bacterial GGTs have also been described, followed by a detailed discussion on various applications of bacterial GGTs in different biotechnological sectors. This review emphasizes the potential of bacterial GGTs as an industrial biocatalyst relevant to the current switch toward green chemistry.

show abstract

Ultrasound enhanced biosynthesis of L-theanine from L-glutamine and ethylamine by recombinant γ-glutamyltranspeptidase

Cited by 11 publications

References 34 publications

From Tea Leaves to Factories: A Review of Research Progress in l-Theanine Biosynthesis and Production

From Tea Leaves to Factories: A Review of Research Progress in l-Theanine Biosynthesis and Production

l‐Theanine Goes Greener: A Highly Efficient Bioprocess Catalyzed by the Immobilized γ‐Glutamyl Transferase from Bacillus subtilis

Bacterial Gamma-Glutamyl Transpeptidase, an Emerging Biocatalyst: Insights Into Structure–Function Relationship and Its Biotechnological Applications

Contact Info

Product

Resources

About