Reaction catalyzed by 5a,11a-dehydrotetracycline reductase (1.3.98.4)

		+		reduced 7,8-didemethyl-8-hydroxy-5-deazariboflavin	=			+
	7-chloro-5a,11a-dehydrotetracycline	+		reduced 7,8-didemethyl-8-hydroxy-5-deazariboflavin	=		7-chlorotetracycline	+		oxidized 7,8-didemethyl-8-hydroxy-5-deazariboflavin