Reaction catalyzed by 4,4'-diapophytoene desaturase (4,4'-diapolycopene-forming) (1.3.8.2)

		+		FAD	=			+		FADH2
	all-trans-4,4'-diapophytofluene	+		FAD	=		all-trans-4,4'-diapo-zeta-carotene	+		FADH2