Dear Roberto, Overnight I recall an additional point:- In chemical crystallography, where standard uncertainties are routinely avaliable for the molecular model from the full matrix inversion in the model refinement, it is of course possible to keep extending your resolution until your bond distance and angles su values go up. Thus if you distrust or do not wish to slavishly follow a Journal's Notes for Authors, such as for Acta Crystallographica Section C to which I referred yesterday, you can, in this way, check yourself the good sense of the data quality criteria required. [This is a similar test to the one that Phil mentioned yesterday ie with respect to scrutinising electron density maps for your protein ie do they show more detail by adding more diffraction data.] Best wishes, John
On Thu, Mar 3, 2011 at 11:29 AM, Roberto Battistutta <roberto.battistu...@unipd.it> wrote: > Dear all, > I got a reviewer comment that indicate the "need to refine the structures at > an appropriate resolution (I/sigmaI of >3.0), and re-submit the revised > coordinate files to the PDB for validation.". In the manuscript I present > some crystal structures determined by molecular replacement using the same > protein in a different space group as search model. Does anyone know the > origin or the theoretical basis of this "I/sigmaI >3.0" rule for an > appropriate resolution? > Thanks, > Bye, > Roberto. > > > Roberto Battistutta > Associate Professor > Department of Chemistry > University of Padua > via Marzolo 1, 35131 Padova - ITALY > tel. +39.049.8275265/67 > fax. +39.049.8275239 > roberto.battistu...@unipd.it > www.chimica.unipd.it/roberto.battistutta/ > VIMM (Venetian Institute of Molecular Medicine) > via Orus 2, 35129 Padova - ITALY > tel. +39.049.7923236 > fax +39.049.7923250 > www.vimm.it > -- Professor John R Helliwell DSc
