preferred_name: 2 L-methionine + H(+) => S-methyl-L-methionine + L-homocysteine
preferred_name_lc: 2 l-methionine + h(+) => s-methyl-l-methionine + l-homocysteine
label: 2 L-methionine + H(+) => S-methyl-L-methionine + L-homocysteine
label_lc: 2 l-methionine + h(+) => s-methyl-l-methionine + l-homocysteine