Table 1. Structural statistics

Data collection
Dataset	Native high res.	Native	Hg derivative	Pt derivative
X-ray source	ESRF (BM30A)	Rotating anode	Rotating anode	Rotating anode
Wavelength	0.9793 Å	1.5418 Å	1.5418 Å	1.5418 Å
Resolution	20.0–1.72 Å	20.0–2.23 Å	20.0–2.23 Å	20.0–2.23 Å
Completeness*	99.4% (99.0%)	96.3% (94.2%)	98.0% (96.2%)	99.2% (94.2%)
Observed reflections	190,082	57,883	70,001	56,944
Unique reflections	25,771	11,678	22,034	23,026
R_merge^†	8.3	4.1	3.1	2.6
Unit cell dimensions
a	109.0 Å	109.4 Å	107.8 Å	109.0 Å
b	43.0 Å	43.0 Å	42.7 Å	43.0 Å
c	53.8 Å	54.1 Å	53.2 Å	54.0 Å
β	104.1°	104.4°	104.0°	104.3°

Refinement	Native high res.
R_cryst^‡	14.4
R_free^‡	19.0			Native high res.
Unique reflections			Overall B-factor	16.021
Working set	24,460		rms deviation from ideality
Test set	1,306		Length	0.017 Å²
Number of atoms			Angles	1.63°
Protein	2,066
Solvent	295

*Highest resolution shell in parentheses.

^{†R_merge = 100 ´
Σ_hΣ_i|I_h,_i – I_h|/ Σ_hΣ_i I_h,i, where I_h is the mean intensity of symmetry-related reflections, I_h,i.
^{‡R_factor = 100 ´
Σ_hkl|F_obs – F_calc| / Σ_hklF_obs, where R_free is calculated for a randomly chosen 5% of reflections (F > 0) omitted from refinement, and R_cryst is calculated for the remaining 95% of reflections (F > 0) included in refinement.}}