Generally during these rigorous bb debates I prefer to stay silent and absorb all the information possible so that I can make an informed decision later on. I fear that I am compelled to contribute in this instance. In regards to the "does this make a difference in the biological interpretation stage" issue, I can state that it does. In my comparatively miniscule career I have run into this issue three times. The first two address Adrian's point...
And (b) even if they do, is this continual improvement even worthwhile? I > am always depressed at how little a model changes from an initial build to > the final one, even when the rfree drops from 35 to 23. All that work! - and > my biological interpretation would have been almost the same at the > beginning as at the end. > In one instance I adopted an orphaned structure and ran it through a slightly more advanced refinement protocol (on the same structure factors) and ended up with a completely different story than the one I started with [1]. Another researcher in my grad lab identified mis-oriented catalytic residues in an existing structure from EDS server maps which affects the biochemistry of the catalytic mechanism [2]. In another case I decided that I would reprocess some images that I had originally indexed and scaled in my "Ooo buttons clicky clicky" stage of learning crystallography and the improved structure factors revealed a alternate conformations for both a critical loop and ligand orientation [3]. And this was all in the last 4 years. So I would posit that the answer is yes there are significant biological insights to be had with the capacity to reassess data in any form. Katherine [1] J Phys Chem Lett. 2010 Oct 7;1(19):2898-2902 [2] Acta Crystallogr D Biol Crystallogr. 2009 Mar;65(Pt 3):294-6. [3] Manuscript in progress ------------ Katherine Sippel, PhD Postdoctoral Associate Baylor College of Medicine
