Table 1. Crystallographic statistics.

Data
PDB accession code	3H53	3H54	3H55	3IGU
Ligand soak	None	GalNAc	Gal	F2-α-Gal-TNP
X-ray source	Rotating anode	Rotating anode	BNL X6A	BNL X6A
Wavelength, Å	1.54	1.54	0.979	0.980
Space Group	C2	C2	C2	C2
Cell a, b, c in Å	153.5, 114.3, 68.4	153.4, 114.2, 68.3	153.9, 114.5, 68.4	151.6, 113.6, 68.4
Cell α, β, γ in °	90., 96.1, 90.	90., 95.6, 90.	90., 96.2, 90.	90., 96.1, 90.
Resolution, Å (last shell)	50-2.01 (2.08-2.01)	50-2.2 (2.28-2.2)	50-1.9 (1.97-1.9)	50-2.15 (2.23-2.15)
No. of Observations (last shell)	772,346 (60,051)	356,155 (24,762)	319,671 (32,173)	265,173 (21,625)
Unique Observations (last shell)	77,785 (7,283)	59,205 (5,733)	87,369 (8,937)	62,455 (6,056)
Completeness, % (last shell)	99.3 (93.0)	99.1 (95.9)	95.8 (98.2)	99.7 (97.4)
Multiplicity (last shell)	9.9 (8.2)	6.0 (4.2)	3.7 (3.6)	4.2 (3.5)
Rsym (last shell)	0.085 (0.610)	0.106 (0.674)	0.117 (0.698)	0.078 (0.634)
<I/σI> (last shell)	29.0 (3.2)	15.9 (2.0)	10.1 (1.7)	17.6 (1.8)
Refinement
Rwork / Rfree	0.161/0.194	0.165/0.205	0.196/0.235	0.164/0.199
No. of Atoms: Protein	6192	6192	6192	6192
Carbohydrate	237	267	285	240
Water	735	655	898	675
Other	102	90	26	90
Average B factor, Å2: Protein	26.0	33.3	20.8	26.0
Ligand	43.8	37.0	21.7	40.1
Ramachandran: Favored	90.8%	90.1%	89.6%	89.9%
Allowed	8.4%	9.2%	9.5%	9.5%
Generous	0.5%	0.5%	0.6%	0.3%
Forbidden	0.3%	0.3%	0.3%	0.3%
RMS Deviations: Bonds, Å	0.007	0.007	0.007	0.007
Angles, °	1.05	1.11	1.09	1.10

R_sym=Σ_hΣ_i|I_h,i-<I_h>|/Σ_hΣ_i|I_h,i|, where I_h,i is the i^th intensity measurement of reflection h and <I_h> is the average intensity of that reflection.

R_work, R_free=Σ_h|F_P-F_C|/Σ_h|F_P|, where F_C is the calculated and F_P is the observed structure factor amplitude of reflection h for the working or free set, respectively.

Ramachandran statistics are calculated in PROCHECK.