8CM8

Galectin-8 N-terminal carbohydrate recognition domain in complex with 4-(bromophenyl)phthalazinone D-galactal ligand

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	DIAMOND BEAMLINE I24
Synchrotron site	Diamond
Beamline	I24
Temperature [K]	100
Detector technology	PIXEL
Collection date	2021-09-18
Detector	DECTRIS PILATUS3 X 6M
Wavelength(s)	0.99990
Spacegroup name	P 21 21 21
Unit cell lengths	54.710, 62.280, 84.750
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	50.186 - 1.220
R-factor	0.17119
Rwork	0.169
R-free	0.21391
Structure solution method	MOLECULAR REPLACEMENT
RMSD bond length	0.015
RMSD bond angle	1.914
Data reduction software	xia2 (0.3.6.3)
Data scaling software	Aimless (0.7.7)
Phasing software	PHASER (2.7.14)
Refinement software	REFMAC (5.8.0403)

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	50.190	1.252
High resolution limit [Å]	1.220	1.220
Rmerge	0.076	0.050
Rmeas	0.079	0.054
Rpim	0.023	0.022
Number of reflections	82202	6317
<I/σ(I)>	13.5
Completeness [%]	99.9	99.9
Redundancy	11.9	9

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, HANGING DROP	8	293.5	A co-crystal with lactose, grown from 12 mg/ml galectin-8N in 10 mM lactose, 10 mM Tris/HCl pH 8.0, 1 mM TCEP and 150 mM sodium chloride mixed with 25% (w/v) PEG 2000 MME) in a hanging drop, was used to soak the compound by transferring crystals in three steps to soaking drops. These were 2 uL drops with a soaking solution of 20% ethylene glycol, 25% PEG 2000 MME, 10 mM Tris pH 8, 1 mM TCEP, 50 mM NaCl, and 2 mM compound 10. The incubation times in the first two drops were about 10 min and in the third drop about 24 h. Then the crystals were transferred to a cryo solution with the same constituents and flash-frozen in liquid nitrogen.