6-thioguanine + S-adenosyl-L-methionine <=> 6-methylthioguanine + S-adenosyl-L-homocysteine + H(+)
6-thioguanine + s-adenosyl-l-methionine <=> 6-methylthioguanine + s-adenosyl-l-homocysteine + h(+)
6-thioguanine + S-adenosyl-L-methionine <=> 6-methylthioguanine + S-adenosyl-L-homocysteine + H(+)
6-thioguanine + s-adenosyl-l-methionine <=> 6-methylthioguanine + s-adenosyl-l-homocysteine + h(+)