1.6.6.1	nitrate reductase (NADH)	transferred to EC 1.7.1.1	
1.6.6.10	nitroquinoline-N-oxide reductase	transferred to EC 1.7.1.9	
1.6.6.11	hydroxylamine reductase (NADH)	transferred to EC 1.7.1.10	
1.6.6.12	4-(dimethylamino)phenylazoxybenzene reductase	transferred to EC 1.7.1.11	
1.6.6.13	N-hydroxy-2-acetamidofluorene reductase	transferred to EC 1.7.1.12	
1.6.6.2	nitrate reductase [NAD(P)H]	transferred to EC 1.7.1.2	
1.6.6.3	nitrate reductase (NADPH)	transferred to EC 1.7.1.3	
1.6.6.4	nitrite reductase [NAD(P)H]	transferred to EC 1.7.1.4	
1.6.6.5	Recommended Name never specified	transferred to EC 1.7.99.3	
1.6.6.6	hyponitrite reductase	transferred to EC 1.7.1.5