Hello, I have a refined 1.8A structure that I wonder if I could squeeze out some anisotropy information. I did TLS refinement on the protein, and it helped my Rfree. But I would like to ask a biological question based on the thermal movement of only a few waters (7 total). In theory, that is not adding a lot of parameters for anisotropy refinement because I am not refining anisotropy of the whole protein. Correct me if I am wrong. So,
1) How do I use Refmac to refine anisotropic B's on only 7 waters? There is an option to use "mixed" for B factor refinement, but I don't know how to define the atoms. 2) If this can be done, given my resolution, how much confidence can I put in my anisotropy refinement of those waters? In another word, if I do see thermal ellipsoids of the waters, are they believable? And if I don't, is it because my resolution isn't high enough to see it anyways? I have a total of ~1700 atoms, and ~24000 unique reflections at 1.8A resolution. Thanks! Joseph
