Reaction catalyzed by 5-oxopent-3-ene-1,2,5-tricarboxylate decarboxylase (4.1.1.68)

		=			+
	(3E,5R)-5-carboxy-2-oxohept-3-enedioate	=		(2Z,4Z)-2-hydroxyhepta-2,4-dienedioate	+		CO2