. Author manuscript; available in PMC: 2012 Feb 1.

Published in final edited form as: J Biol Inorg Chem. 2010 Oct 31;16(2):285–297. doi: 10.1007/s00775-010-0725-z

Table 2.

Fits obtained to the Cu and Se EXAFS of reconstituted Cu(I) and Cu(II) proteins of H135 mutants by curve-fitting using the program EXCURV 9.2

Sample/fit	F^a	Cu–S			Cu–Se			−E₀
Sample/fit	F^a	No^b	R (Å)^c	DW (Å²)	No^b	R (Å)^c	DW (Å²)	−E₀
Copper EXAFS
Cu(I)Met	0.282	2.7	2.22	0.013				1.92
Cu(I)SeM	0.472	2	2.24	0.009	0.6	2.38	0.010	4.20
Cu(II)Met^d	0.321	3	2.22	0.012				1.89
Cu(II)SeM^d	0.391	2	2.21	0.009	1.0	2.36	0.011	2.00

Sample/fit	F^a	Se–C			Se–Cu^d			−E₀
Sample/fit	F^a	No^b	R (Å)^c	DW (Å²)	No^b	R (Å)^c	DW (Å²)	−E₀
Selenium EXAFS
Cu(I)SeM	0.718	2	1.96	0.005	1.2	2.39	0.009	5.96
Cu(II)SeM	1.031	2	1.95	0.005	1.0	2.36	0.011	5.04

F is a least-squares fitting parameter defined as $F^{2} = \frac{1}{N} \sum_{i = 1}^{N} k^{6} {(Data - Model)}^{2}$

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

Shell occupancy values have been renormalized by multiplying by 4 (the total number of methionines, both coordinating and noncoordinating, in the protein) so as to represent the number of Cu scatterers interacting with the coordinated Se atom