label: 5-methyluridine(341) in tmRNA + S-adenosyl-L-homocysteine + H(+) => uridine(341) in tmRNA + S-adenosyl-L-methionine
label_lc: 5-methyluridine(341) in tmrna + s-adenosyl-l-homocysteine + h(+) => uridine(341) in tmrna + s-adenosyl-l-methionine