Table S1. X-ray data collection statistics

Space Group

P3121

Resolution () (outer bin range)

32 - 2.6 (2.74-2.6)

Completeness

0.97 (0.86)

Multiplicity

10.2 (9.3)

Wilson plot B (2)

65

Rmerge*

0.134 (1.005)

Rmeas **

0.141 (1.066)

<<I>/<s>>

17.2(2.7)

Refinement Statistics

R factor ***  (working set)

0.230

RFree

0.305

<B> (2) (mean, overall)

57

Nreflections (Nfree)

7786 (867)

Natoms (Nwater)

1808 (37)

Rmsd bond length ()

0.013

Values in parentheses apply to the highest resolution shell

* Rmerge = SSi |Ih - Ihi| / SSi Ih , where Ih is the mean intensity for reflection h

** Rmeas = S(n/n-1)Si |Ih - Ihi| / SSi Ih , the multiplicity weighted Rmerge

***   R = S|FP-Fcalc|/SFP