Structural insight into the substrate- and dioxygen-binding manner in the catalytic cycle of rieske nonheme iron oxygenase system, carbazole 1,9a-dioxygenase

Table 3 Average bond lengths (Å) between nonheme iron and atoms in the catalytic cycle

State^a	H183	H187	D333	D333	CAR	CAR	Peroxide	Peroxide
State^a	NE2	NE2	OD1	OD2	C1	C9a	O1	O2
(1) Resting	2.1	2.2	2.1	2.8	–	–	–	–
(Oxy: Fd^rest)	2.1	2.2	2.1	2.8	–	–	–	–
(2) Reduced	2.1	2.1	2.0	2.6	–	–	–	–
(Oxy: Fd^red)	2.1	2.1	2.0	2.6	–	–	–	–
(2’) CAR-bound	2.1	2.3	2.0	2.6	4.3	4.2	–	–
(Oxy: Fd^CAR)	2.1	2.3	2.0	2.6	4.3	4.2	–	–
(3) Reduced CAR-bound	2.2	2.1	A^b:1.9	A^b:2.7	4.6	4.7	–	–
(Oxy: Fd^red-CAR)	2.2	2.1	B&C^b:2.0	B&C^b:2.2	4.6	4.7	–	–
(3’) Oxygen-bound	2.1	2.1	2.0	2.7	–	–	2.6	2.0
(Oxy: Fd^O2)	2.1	2.1	2.0	2.7	–	–	2.6	2.0
(4) CAR- and oxygen-bound	2.1	2.1	1.9	2.6	4.6	4.5	A^b:2.5	A^b:1.9
(Oxy: Fd^CAR-O2)							B&C^b:1.8	B&C^b:1.8

ISSN: 1472-6807