Summary of data collection and refinement statistics.

aValues in parentheses correspond to highest resolution shell.bRmerge = Σ Σ |I(k)−|/Σ I(k) where I(k) and represent the intensity values of the individual measurements and the corresponding mean values. The summation is over all unique measurements.cRwork = Σ ∥Fobs|−k|Fcalc∥/|Fobs| where Fobs and Fcalc are the observed and calculated structure factors, respectively. Rfree is the sum extended over a subset of reflections (4.2%) excluded from all stages of the refinement.dAs calculated using MOLPROBITY [82].eMaximum-Likelihood based coordinate error as determined by PHENIX [64].Summary of data collection and refinement statistics.