putrescine + S-adenosyl-L-methionine = N-methylputrescine + S-adenosyl-L-homocysteine + H(+)
putrescine + s-adenosyl-l-methionine = n-methylputrescine + s-adenosyl-l-homocysteine + h(+)
putrescine + S-adenosyl-L-methionine = N-methylputrescine + S-adenosyl-L-homocysteine + H(+)
putrescine + s-adenosyl-l-methionine = n-methylputrescine + s-adenosyl-l-homocysteine + h(+)