Reaction catalyzed by adenylosuccinate lyase (4.3.2.2)

		=			+
	(S)-2-[5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamido]succinate	=		fumarate	+		5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide