Cant you more or less get a good idea of the occupancy from an anomalous difference map? You dont say what your wavelength is, but Tb and ca will probably have very different anomalous signals. With 1.3A data you should get a very clear map -I use the Ss to give a measure of expected signal then look at the Tb? Ca? sites to get an indication.. Eleanor
On Wed, 5 Mar 2025 at 13:07, Miha Pavšič <miha.pav...@fkkt.uni-lj.si> wrote: > Dear all, > > I have a question regarding alternative ion occupancy refinement > (anomalous). > > We are working with a dataset from a metal ion binding protein with two > ion binding sites, one predominantly occupied by Tb(III), the other by > Ca(II). Dataset contains anomalous signal, collected at 1.3 Å wavelength. > The expected occupancy (Tb+Ca) at each of the sites is believed to be 1 or > very close to 1. I am wondering if it is possible to somehow refine > (phenix.refine) using anomalous data a model with two alternative ions at > each site (i.e. Tb and Ca), or just place the predominant one at each of > the two sites and call it a day? > > Any hints much appreciated! > > Best regards, > Miha > > -- > Assoc. Prof. Miha Pavšič > University of Ljubljana, Faculty of Chemistry and Chemical Technology, > Chair of Biochemistry > Večna pot 113, SI-1000 Ljubljana, Slovenia > > ######################################################################## > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 > > This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a > mailing list hosted by www.jiscmail.ac.uk, terms & conditions are > available at https://www.jiscmail.ac.uk/policyandsecurity/ > ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
