title: Enzymatic synthesis of gamma-glutamylvaline to improve the bitter taste of valine.
abstract: The taste of several bitter amino acids is reduced, sourness produced, and preference increased by gamma-glutamylization. An enzymatic method for synthesizing gamma-Glu-Val involving bacterial gamma-glutamyltranspeptidase (GGT) was developed. The optimum reaction conditions for the synthesis of gamma-Glu-Val were 20 mM Gln, 300 mM Val, and 0.04 U/ml GGT, pH 10. After 3-hr incubation at 37 degrees C, 17.6 mM gamma-Glu-Val was obtained, with the yield being 88%. gamma-Glu-Val was purified on a Dowex 1 x 8 column and then identified by NMR.
authors.affiliation: Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Kenji
authors.initials: K
authors.lastname: Kato
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Kumagai
mesh_terms: D004151:Dipeptides / Q000096:biosynthesis*; D004926:Escherichia coli / Q000201:enzymology; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D013649:Taste; D014633:Valine; D005723:gamma-Glutamyltransferase / Q000378:metabolism
chemical_list: D004151:Dipeptides; C482621:gamma-glutamylvaline; D005723:gamma-Glutamyltransferase; D014633:Valine