label: 5-methoxycarbonylmethoxyuridine(34) in tRNA + S-adenosyl-L-homocysteine => 5-carboxymethoxyuridine(34) in tRNA + S-adenosyl-L-methionine
label_lc: 5-methoxycarbonylmethoxyuridine(34) in trna + s-adenosyl-l-homocysteine => 5-carboxymethoxyuridine(34) in trna + s-adenosyl-l-methionine