2-aminobut-2-enoate + hydrogen sulfide + H(+) => L-homocysteine
2-aminobut-2-enoate + hydrogen sulfide + h(+) => l-homocysteine
2-aminobut-2-enoate + hydrogen sulfide + H(+) => L-homocysteine
2-aminobut-2-enoate + hydrogen sulfide + h(+) => l-homocysteine