Table 2. Comparison of Calculated Geometric Parameters of the ES Complex for the Wild-Type Enzyme and Y194F Mutant with Available X-ray Structures of AHL Lactonases.

	bond length (Å)
	wild type (ES)	Y194F (ES)	2A7M (11) (apo)	2BTN (12) (apo)	2BR6 (12) (EI)	wild type (16) (EP)
Zn1−Zn2	3.49 ± 0.11	3.51 ± 0.11	3.3	3.4	3.4	3.7
Zn2−Oδ1(Asp108)	2.34 ± 0.13	2.36 ± 0.14	2.3	2.3	2.3	2.8
Zn1−Oδ2(Asp191)	2.90 ± 0.18	3.08 ± 0.29	2.6	2.6	2.6	2.4
Zn2−Oδ2(Asp191)	2.22 ± 0.08	2.21 ± 0.08	2.0	2.1	2.1	2.1
Zn2−Oδ1(Asp191)	3.04 ± 0.15	3.07 ± 0.15	3.3	3.2	3.2	2.7
Zn1−Nε2(His104)	2.05 ± 0.06	2.04 ± 0.06	2.1	2.3	2.3	2.1
Zn1−Nδ1(His106)	2.09 ± 0.08	2.07 ± 0.07	2.2	2.3	2.3	2.1
Zn1−Nε2(His169)	2.02 ± 0.06	2.02 ± 0.06	2.1	2.3	2.2	2.1
Zn2−Nε2(His109)	2.01 ± 0.06	2.03 ± 0.06	2.0	2.2	2.1	2.1
Zn2−Nε2(His235)	2.01 ± 0.06	2.02 ± 0.06	2.1	2.2	2.2	2.0
Zn1−Ow	1.99 ± 0.06	1.98 ± 0.05	2.0	2.1	2.0	—a
Zn2−Ow	2.14 ± 0.08	2.12 ± 0.07	2.0	2.2	2.2	—a
O2−Zn2	3.79 ± 0.32	4.83 ± 0.54	—a	—a	—a	—a
Ow−Oδ2(Asp108)	2.77 ± 0.09	2.78 ± 0.10	2.9	2.6	2.5	—a
Hw−Oδ2(Asp108)	1.84 ± 0.10	1.84 ± 0.11	—a	—a	—a	—a
C1−Ow	2.58 ± 0.36	3.74 ± 0.63	—a	—a	—a	—a
O1−HO(Tyr194)	1.82 ± 0.20	—a	—a	—a	—a	—a
O3−Ob	2.73 ± 0.15	2.76 ± 0.23	—a	—a	—a	2.6
O3−Hb1	1.79 ± 0.17	1.81 ± 0.26	—a	—a	—a	—a
O3−N(Phe107)	4.05 ± 0.73	4.05 ± 0.74	—a	—a	—a	3.8
O3−HN(Phe107)	3.11 ± 0.27	3.16 ± 0.74	—a	—a	—a	—a
Ob−N(Phe107)	3.12 ± 0.27	3.12 ± 0.37	—a	—a	—a	3.0
Ob−HN(Phe107)	2.24 ± 0.33	2.25 ± 0.46	—a	—a	—a	—a

^aValue not applicable.