Table 1. Data collection and refinement statistics.

PDB code	5G28* (type A crystal)	5G54* (type B crystal)	5G2A* (Br ion crystal)	5G2D* (T102N)	5G2C* (T102D)
Data collection
Space group	C121	C121	C121	C121	C121
a, b, c (Å)	102.76, 49.40, 69.33	102.72, 49.43, 77.03	102.77, 48.85, 69.36	103.25, 49.45, 78.40	103.44, 50.03, 77.79
α, β, γ (°)	90, 109.85, 90	90, 131.16, 90	90, 110.13, 90	90, 131.89, 90	90, 131.47, 90
Resolution (Å)	65.21–1.57 (1.62–1.57)†	40.00–2.0 (2.05–2.0)†	65.13–2.17 (2.21–2.17)†	58.36–1.80 (1.83–1.80)†	58.28–2.31 (2.34–2.31)†
Rmerge (%)	11.1 (65.9)†	10.2 (69.3)†	5.9 (20.9)†	7.0 (39.3)†	6.0 (31.3)†
I/σI	30.81 (4.23)†	11.1 (1.65)†	35.46 (7.59)†	22.67 (2.57)†	14.43 (1.86)†
Completeness (%)	97.4 (93.06)†	99.3 (96.4)†	99.0 (98.8)†	97.1 (81.9)†	94.5 (73.5)†
Redundancy	4.4 (2.7)†	5.6 (4.9)†	5.8 (3.9)†	4.6 (2.4)†	4.3 (2.0)†
Refinement
Resolution (Å)	65.21–1.57	40.0–2.0	65.13–2.17	58.36–1.80	58.28–2.31
No. of reflections	42,520	18,695	16,316	25,345	11,889
Rwork/Rfree (%)	15.40/19.38	17.60/22.52	15.31/20.71	17.51/20.52	19.45/23.88
No. of atoms
Protein	2,072	2,105	2,072	2,095	2,101
Retinal	20	20	20	20	20
Water	136	84	59	93	15
Lipid fragments	99	101	—	108	108
Chloride	2	2	2	2	1
B factors (Å2)
Protein	23.82	19.03	29.22	22.87	29.27
Retinal	15.57	11.06	21.66	17.02	22.14
Water	39.86	34.65	40.69	40.63	37.52
Lipid fragments	48.21	44.54	—	48.38	47.48
Chloride ions	32.77	38.75	Br− (67.85)	40.97	58.43
r.m.s. deviations
Bond lengths (Å)	0.026	0.018	0.021	0.023	0.019
Bond angles (°)	1.92	1.98	1.83	1.90	1.91
Crystal size (μm)	50 × 50 × 50	30 × 30 × 30	50 × 50 × 50	50 × 50 × 50	50 × 50 × 50
Radiation dose (MGy)	0.04	0.12	0.04	0.04	0.04

PDB, Protein Data Bank; r.m.s., root mean squared.

^*Number of crystal used for data collection: 1.

^†Highest-resolution shell is shown in parenthesis.