Hi, I try to model the structure of a protein-ligand complex with Xplor-NIH using pseudo contact shifts (PCSs) as NMR restraints and the PARArestraints module of Xplor. Therefore, I immobilized a paramagnetic tag to the protein C-terminus carrying a lanthanide ion. I could determine the PCS tensor values very accurately with the program Numbat (developed by the group of G. Otting, ANS Canberra). For the calculation in Xplor-NIH I use the xpcs module. Unfortunately, it seems that the xpcs function can calculate the PCS only with respect to one lanthanide ion at one time. However, the protein is dimeric and thus the PCS values should be the sum for the two lanthanide positions. Do you have an idea how I can perform the calculation considering both lanthanides together? I tried e.g. an ambiguous assignment (OR statement) in the PCS input table which however leads to an error. Any help would be really appreciated. Thanks a lot.
Best regards Georg -- Georg Künze Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstraße 16-18, 04107 Leipzig http://www.uni-leipzig.de/~biophys<http://www.uni-leipzig.de/%7Ebiophys> Tel.: +49(0)-341 9715744 Mail: [email protected] _______________________________________________ Xplor-nih mailing list [email protected] https://dcb.cit.nih.gov/mailman/listinfo/xplor-nih
