L-Glutamine → Glycine methyl ester

The synthesis reaction was carried out by incubating a reaction liquid containing 100 mM test amino acid methyl ester, 150 mM L-glutamine, 100 mM borate buffer (pH 9.0), 10 mM EDTA and enzyme (0.05 U/ml) for 3 hours at 25° C., followed by determination of the quantity of the produced peptides by HPLC. As a result, 52.19 mM glycyl-L-glutamine was produced in the case of using glycine methyl ester as the L-amino acid methyl ester, 5.94 mM L-valyl-L-glutamine was produced in the case of using L-valine methyl ester, 0.59 mM L-isoleucyl-L-glutamine was produced in the case of using L-isoleucyl-L-glutamine, 4.31 mM L-methionyl-L-glutamine was produced in the case of using L-methionine methyl ester, 3.67 mM L-phenylalanyl-L-glutamine was produced in the case of using L-phenylalanine methyl ester, 40.44 mM L-seryl-L-glutamine was produced in the case of using L-serine methyl ester, 3.85 mM L-threonyl-L-glutamine was produced in the case of using L-threonine methyl ester, 0.23 mM L-glutaminyl-L-glutamine was produced in the case of using L-glutamine methyl ester, 1.24 mM L-tyrosyl-L-glutamine was produced in the case of using L-tyrosine methyl ester, 6.52 mM L-arginyl-L-glutamine was produced in the case of using L-arginine methyl ester, and 8.22 mM L-aspartyl-α-L-glutamine was produced in the case of using L-aspartic acid-α-methyl ester. In addition, peptides composed of the corresponding amino acids and L-glutamines were also confirmed to be produced in the case of using L-leucine methyl ester, L-asparagine methyl ester, L-lysine methyl ester, L-aspartic acid-β-methyl ester, L-aspartic acid-α,β-dimethyl ester or L-glutamic acid-γ-methyl ester as the amino acid methyl ester (determination of quantity of these was not performed since no standard preparation was available).