guanosine(18) in tRNA + S-adenosyl-L-methionine = 2'-O-methylguanosine(18) in tRNA + S-adenosyl-L-homocysteine + H(+)
guanosine(18) in trna + s-adenosyl-l-methionine = 2'-o-methylguanosine(18) in trna + s-adenosyl-l-homocysteine + h(+)
"tRNA (guanosine(18)-2'-O)-methyltransferase"
"trna (guanosine(18)-2'-o)-methyltransferase"