. 2014 Aug 5;53(36):5759–5770. doi: 10.1021/bi500767x

Table 2. Relevant Active-Site Bond Lengths (in Å) and Angles (in Degrees) As Derived from the QM/MM-Optimized Models and the 2.00 Å Resolution Crystal Structure of Cys-Bound Fe(II)CDO.

species	Fe–His₈₆	Fe–His₈₈	Fe–His₁₄₀	Fe–S_Cys	Fe–N_Cys	Fe–X^a	His₈₆–Fe–X
Cys-Fe(II)CDO, 4JTO^b	1.893	2.199	2.110	2.291	2.262	n.a.	n.a.
(OH^–/Cys)-Fe(III)CDO	2.347	2.135	2.238	2.436	2.252	1.899	168.6
(H₂O/Cys)-Fe(III)CDO	2.148	2.221	2.100	2.446	2.175	2.219	169.1
Cys-Fe(III)CDO	2.116	2.147	2.109	2.436	2.170	n.a.	n.a.
(N₃^–/Cys)-Fe(III)CDO^c	2.073	2.154	1.994	2.261	2.069	1.930	177.6

X refers to the ligating atom of the sixth ligand (hydroxide, water, or azide) bound to iron.

Crystal structure at 2.00 Å resolution, ref (23).

Optimized as an S = ¹/₂ species.