Table 2. Electron-density map correlation coefficients.

Electron-density maps were recalculated using fixed 300 × 300 × 300 grids for the calculation of correlation coefficients to avoid interpolation errors. We re-ran noncrystallographic symmetry averaging using matrices and masks derived at 3.1 Å resolution as well as using matrices and masks derived at 2.5 Å resolution. The experimental maps are calculated using unweighted 2F _obs − F _ave as coefficients and phases derived from averaged maps.

		Correlation coefficient (%)
3.1 Å experimental versus 2.5 Å experimental phases
3.1 Å map	3.1 Å map	68.9
3.1 Å map	2.8 Å map	66.1
3.1 Å map	2.5 Å map	64.5
2.5 Å experimental versus 2.5 Å experimental phases
3.1 Å map	2.8 Å map	94.2
3.1 Å map	2.5 Å map	91.3
2.8 Å map	2.5 Å map	93.6
2.5 Å experimental versus 2.5 Å calculated phases†
2.5 Å map	2.5 Å map	76.8
3.1 Å map	3.1 Å map	74.8
3.1 Å map	2.5 Å map	78.7

^†Amplitudes and phases for weighted 2F _obc − F _calc maps were prepared by the refinement program REFMAC, where F _calc are the calculated structure factors from final refined atomic model.