. Author manuscript; available in PMC: 2012 Dec 20.

Published in final edited form as: Biochemistry. 2011 Nov 22;50(50):10819–10828. doi: 10.1021/bi201193j

Table 1.

Fits obtained to the EXAFS of the M314H variant of peptidylglycine monooxygenase

	F^a	No^b	R (Å)^c	DW (Å²)	No^b	R (Å)^c	DW (Å²)	No^b	R (Å)^c	DW (Å²)	−E₀
Oxidized Proteins

		Cu-N(His) ^d			Cu-O/N ^e			Cu-S
pH 7 fit A	0.403	2.5	1.96	0.015	1.5	1.96 ^e	0.015				5.20
fit B	0.478	3	1.97	0.014	1	1.96^e	0.014				4.56
fit C	0.332	2.5	1.96	0.015	1.5	1.96^e	0.015
					0.5	2.33	0.006				4.98
Reduced Proteins
		Cu-N(His1) ^d			Cu-O/N			Cu-S
pH 7 fit A	0.580	2.5	1.91	0.018	0.5	2.49	0.016				0.79
pH 7 fit B	0.664	2.5	1.90	0.018							0.57
pH 3.5	0.543	2.0	1.90	0.017				0.5	2.25	0.007	0.92

F is a least-squares fitting parameter defined as $F^{2} = \frac{1}{N} \sum_{i = 1}^{N} k^{6} {(D a t a - M o d e l)}^{2}$

Coordination numbers are generally considered accurate to ± 25%

In any one fit, the statistical error in bond-lengths is ±0.005 Å. However, when errors due to imperfect background subtraction, phase-shift calculations, and noise in the data are compounded, the actual error is probably closer to ±0.02 Å.

Fits modeled histidine coordination by an imidazole ring, which included single and multiple scattering contributions from the second shell (C2/C5) and third shell (C3/N4) atoms respectively. The Cu-N-Cx angles were as follows: Cu-N-C2 126°, Cu-N-C3 −126°, Cu-N-N4 163°, Cu-N-C5 −163°.

First-shell distances of the Cu-N(His) and Cu-N/O (non-His) shells were constrained to be equal in fits to the oxidized proteins.