Table S2.

Data collection and refinement statistics

Space group	P 21
Unit cell parameters
a, b, c, Å	48.783, 43.244, 61.234
α, β, γ, °	90, 111.52, 90
Resolution range, Å	45.38–1.55 (1.58–1.55)*
Rmerge, %	5.3 (49.9)
CC1/2, %	99.9 (76.7)
<I/σ(I)>	14.0 (2.1)
No. of reflections	113,930 (5,098)
No. of unique reflections	34,495 (1,686)
Multiplicity	3.3 (3.0)
Completeness, %	99.4 (99.0)
Rwork/Rfree†, %	15.68/18.77
rmsd from ideal
Bond lengths, Å	0.006
Bond angles, °	1.269
Average isotropic B factors, Å2
Main chain	13.03
Side chain	17.81
Water molecules	28.98
Ligands: BME, PGE, P6G	35.84
Ramachandran plot‡, %
Residues in favored regions	98.7
Residues in allowed regions	1.3
Outliers	0.0
Rotamer‡ outliers	1.0

^*Values in parentheses are for the highest-resolution shell.

^†R_free is calculated using a random 5% of data excluded from the refinement.

^‡Ramachandran and rotamer analysis was carried out using Molprobity.