label: guanosine(37) in tRNA + S-adenosyl-L-methionine = N(1)-methylguanosine(37) in tRNA + S-adenosyl-L-homocysteine + H(+)
label_lc: guanosine(37) in trna + s-adenosyl-l-methionine = n(1)-methylguanosine(37) in trna + s-adenosyl-l-homocysteine + h(+)