γ-Glutamyl transpeptidase-catalyzed synthesis of naturally occurring flavor enhancers

Speranza, Giovanna; Morelli, Carlo F.

doi:10.1016/j.molcatb.2012.03.014

Cited by 36 publications

(43 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recycling of immobilized ekGGT was performed by evaluating over time the residual activity of the enzyme in the synthesis of γ‐glutamylmethionine in Tris‐HCl buffer (pH 9, 0.05 M) . After each reaction cycle (3 days), the reaction mixture was filtered under reduced pressure and the immobilized biocatalyst was re‐used for the following reaction runs.…”

Section: Resultsmentioning

confidence: 99%

“…5 U of OCGLX‐agarose‐ekGGT were added to a L‐methionine solution (333 mM) in Tris‐HCl buffer (pH 9, 0.05 M) in the presence of a 10 % molar excess GSH. After 72 hours, the reaction product was isolated by preparative ion exchange chromatography in 42 % yield. This result was consistent with the data obtained by using the non‐immobilized enzyme …”

Section: Resultsmentioning

confidence: 99%

“…Although being nearly tasteless in themselves, kokumi compounds are able to elicit strong taste sensations, especially when associated with protein‐rich food, thus acting as true flavor enhancers . Despite their simple chemical structure, the synthesis of γ‐glutamyl derivatives through the classical peptide chemistry is troublesome due to the need of protection and deprotection steps . Therefore, an enzymatic approach does represent an appealing solution for their supply.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Immobilization of γ‐Glutamyl Transpeptidase from Equine Kidney for the Synthesis of kokumi Compounds

et al. 2019

Self Cite

View full text Add to dashboard Cite

γ‐Glutamyl transpeptidase from equine kidney (ekGGT, E.C. 2.3.2.2) is an intrinsic membrane enzyme which transfers the γ‐glutamyl moiety of glutathione to amino acids and peptides, thus producing γ‐glutamyl derivatives. An immobilization study of ekGGT was carried out with the aim to develop a robust biocatalyst for the synthesis of γ‐glutamyl amino acids which are known as kokumi compounds. Heterofunctional octyl‐glyoxyl‐agarose resulted in a high immobilization yield and activity recovery (93 % and 88 %, respectively). Immobilized ekGGT retained more than 95 % activity under reaction conditions (Tris‐HCl, pH 9, 0.05 M) after 6 days, whereas the residual activity after 6 reaction cycles (18 days) was 85 %. The synthesis of γ‐glutamylmethionine catalyzed by octyl‐glyoxyl‐agarose‐ekGGT afforded the product in 42 % yield (101 mg). The immobilized ekGGT was characterized by Raman spectroscopy. The immobilization protocol developed for ekGGT could be of general applicability to membrane proteins.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Immobilization of γ‐Glutamyl Transpeptidase from Equine Kidney for the Synthesis of kokumi Compounds

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…S1). Its enzymatic activity, expressed as lmoles of p-nitroaniline liberated through the transpeptidation reaction with GPNA as the donor and glycylglycine as the acceptor at pH 8.5 and 22°C [32][33][34][35][36][37][38][39][40][41] pH-activity profile pH-rate profiles for the hydrolase and the transpeptidase activities were determined with the standard method, with GPNA as the donor and glycylglycine as the acceptor [13,32,41]. We found that the hydrolase activity reached a maximum at a pH of~9, and then decreased, giving a bell-shaped curve.…”

Section: Resultsmentioning

confidence: 99%

“…We reported recently the chemoenzymatic synthesis of c-glutamyl derivatives of methionine and S-substituted cysteines as examples of flavor enhancers found in plants of the genus Allium [39]. The synthesis relied on the use of an enzyme of mammalian origin, so the obtained products were not suitable for human use.…”

mentioning

confidence: 99%

pH‐Dependent hydrolase, glutaminase, transpeptidase and autotranspeptidase activities of Bacillus subtilis γ‐glutamyltransferase

et al. 2013

Self Cite

View full text Add to dashboard Cite

c-Glutamyltransferases (c-GTs) are heterodimeric enzymes that catalyze the transfer of a c-glutamyl group from a donor species to an acceptor molecule in a transpeptidation reaction through the formation of an intermediate c-glutamyl enzyme. In our search for a c-GT from a generally recognized as safe microorganism suitable for the production of c-glutamyl derivatives with flavor-enhancing properties intended for human use, we cloned and overexpressed the c-GT from Bacillus subtilis. In this study, we report the behavior of B. subtilis c-GT in reactions involving glutamine as the donor compound and various acceptor amino acids. The common thread emerging from our results is a strong dependence of the hydrolase, transpeptidase and autotranspeptidase activities of B. subtilis c-GT on pH, also in relation to the pK a of the acceptor amino acids. Glutamine, commonly referred to as a poor acceptor molecule, undergoes rapid autotranspeptidation at elevated pH, affording oligomeric species, in which up to four c-glutamyl moieties are linked to a single glutamine. Moreover, we found that D-glutamine is also recognized both as a donor and as an acceptor substrate. Our results prove that the B. subtilis c-GT-catalyzed transpeptidation reaction is feasible, and the observed activities of c-GT from B. subtilis could be interpreted in relation to the known ability of the enzyme to process the polymeric material c-polyglutamic acid.

show abstract

Enzymatic Synthesis of γ‐Glutamyl Dipeptides Catalysed by Mutant E. coli γ‐Glutamyltransferases

et al. 2022

Self Cite

View full text Add to dashboard Cite

γ‐Glutamyltransferases (GGTs) from different sources have been proposed in recent times as biocatalysts for the enzymatic synthesis of naturally occurring γ‐glutamyl derivatives with flavor‐enhancer properties and interesting biological activities. Although the enzymatic approach is considered as a viable alternative to both the troublesome and low‐yielding extraction from natural sources and synthesis through peptide chemistry requiring protection/deprotection steps, yields are not completely satisfactory, due to the intervention of GGT‐catalysed hydrolysis and autotranspeptidation side‐reactions. Here, the design and the use as biocatalyst for preparative purposes of two mutants of E. coli GGT are described. The design of mutants was pursued by docking‐guided identification of residues putatively involved in interaction with the acceptor substrate, thus probably representing a first identification of residues constituting the still elusive and poorly characterized acceptor substrate binding site of the enzyme.

show abstract

γ-Glutamyl transpeptidase-catalyzed synthesis of naturally occurring flavor enhancers

Cited by 36 publications

References 38 publications

Immobilization of γ‐Glutamyl Transpeptidase from Equine Kidney for the Synthesis of kokumi Compounds

Immobilization of γ‐Glutamyl Transpeptidase from Equine Kidney for the Synthesis of kokumi Compounds

pH‐Dependent hydrolase, glutaminase, transpeptidase and autotranspeptidase activities of Bacillus subtilis γ‐glutamyltransferase

Enzymatic Synthesis of γ‐Glutamyl Dipeptides Catalysed by Mutant E. coli γ‐Glutamyltransferases

Contact Info

Product

Resources

About