Crystal structures of a halophilic archaeal malate synthase from Haloferax volcanii and comparisons with isoforms A and G

Table 1 Crystallographic Data and Refinement Statistics

	Native^a	Pb Derivative	Glyoxylate Complex	Ternary Complex
Data Collection
Unit cell dimensions
a = b (Å)	156.4	155.4	155.0	154.8
c (Å)	141.5	139.5	141.8	142.1
α = β (°)	90	90	90	90
γ (°)	120	120	120	120
Resolution (Å)	30-2.70	30-2.10	20-2.51	30-1.95
	(2.80-2.70)	(2.18-2.10)	(2.59-2.51)	(2.02-1.95)
Number of observations
Total	104,473	271,479	75,347	401,261
Unique	18,255	73,241^b	22,203	47,508
Redundancy	5.7 (5.7)	3.7 (3.6)^b	3.4 (3.2)	8.4 (7.8)
Complete (%)	100.0 (100.0)	99.5 (100.0)	98.8 (97.3)	100.0 (100.0)
R_sym^c	0.090 (0.383)	0.103 (0.374)	0.096 (0.453)	0.099 (0.806)
<I/σ(I)>	14.2 (4.2)	11.5 (3.3)	8.7 (2.5)	15.2 (2.3)
Wilson B factor (Å²)	68.6	33.6	56.0	33.5
Figure of Merit from SOLVE		0.36
Figure of Merit after RESOLVE		0.71
Cullis R factor		0.74
R_iso/R_ano		0.285/0.054
Refinement
R_work^d	0.1984		0.1921	0.2029
R_free^e	0.2626		0.2476	0.2390
R.m.s. deviations
Bond lengths (Å)	0.014		0.017	0.017
Bond angles (°)	2.27		2.07	2.47
Mean isotropic B factor (Å²)	58.34		58.33	47.65
Φ/Ψ angles^f
Most favored (%)	89		86.3	91.8
Additional allowed (%)	11		13	7.9
Generously allowed (%)	0		0.3 (Thr 276)	0.3 (Glu 24)
Disallowed (%)	0		0.3 (Glu 24)	0

Values in parentheses are for the high-resolution shell. ^aAt 3 mM glyoxylate, 13 mM Mg²⁺. ^bFriedel mates treated as independent reflections for anomalous phasing. ^cR_sym = Σ_hkl |I - <I>|/Σ_hkl (I), where I is the observed intensity, and <I> is the average intensity for multiple observations of symmetry related reflections. ^dR_work is the R_factor for 95% of data used during refinement, where R_factor = Σ_hkl ||F_o|-|F_c||/Σ_hkl|F_o|. ^eR_free is the R_factor for 5% of the data not used in refinement. ^fFor non-Gly and non-Pro residues only.

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