Hi, I saw the same thing once and the cause was that the crystal had been hideously over-exposed during data collection. As a result, essentially all the spots at lower than 2.5A resolution were overloaded. The Wilson plot was thus more or less flat at medium to high resolution and accordingly the Wilson B was very low (less than 1A**2). As in your case, the first indication of the problem was that the atomic B-factors were refining to ridiculously low values (although of course REFMAC was only doing the right thing). Hope that helps, Joe
> Hi Bill, > > if you put a water oxygen in place where a heavier atom is, then water > oxygen's B-factor will refine to a value close to zero. This is the > feature > that we currently use as one of many criteria to develop automatic > identification and building of metals. > > Overall Wilson B-factor of 0.6A**2 tells that there is something weird > about > the data. What is the resolution? > > Pavel. > > PS> As Nat mentioned, PHENIX related questions are best to send to PHENIX > (and not CCP4) mailing list: > http://www.phenix-online.org/ > > > On Mon, Dec 20, 2010 at 7:34 AM, Zhibing Lu <billz...@gmail.com> wrote: > >> Hi All, >> Recently I solved a structure in which some water molecules have >> Bfactors >> at 0 and overall wilson Bfactor is 0.654 based on PHENIX refinement. Is >> it >> possible? >> Bill Lu >> >
