label: phosphoethanolamine + S-adenosyl-L-methionine => N-methylethanolamine phosphate + S-adenosyl-L-homocysteine + H(+)
label_lc: phosphoethanolamine + s-adenosyl-l-methionine => n-methylethanolamine phosphate + s-adenosyl-l-homocysteine + h(+)