Hi,
I have a structure with 3 different resolutions, 2.3A, 2.4A, 2.5A, the
qualities seem normal, not good but also not too bad.
The B factors along a,b,c axis have notable difference, for example B(a)=80,
B(b)=30, B(c)=20. We used molecular
replacement to solve the structure. For the 2.3A data, the final Rfree is
0.265 from phenix.refine without tls since tls will
increase the Rfree much. But for the 2.4A data, the Rfree wonnot low down to
0.32, though the map seems not bad(with
only a few solvent atoms). And for the 2.5A data the Rfree is even higher
than 0.4. For all of them I used thinshell and
followed the same procedure:
MR-->rigid body refinement-->restrain
refinement-->phenix.autobuild-->manually check-->phenix.refine(ordered
solvent)
And autobuild can always build more than 80% residues with mostly side
chains.
This is not a big structure with no more than 1000 residues in 2
molecules. I wonder why the R values keep so high.
Do I need to run anisotropic refinement for such resolutions? Or any other
reasons?
Thanks!
