Hello Ning-- > For our protein, only N-H RDCs is used for refinement calculations, > we get the good Q value of 0.216 and good correlation between > experimental RDCs and predicted RDCs, we also get the good Q value > of 0.11 with the only HACA RDCs for refinement calculations(scale > factor is 1 relative to NH ) and good correlation between > experimental RDCs and predicted RDCs, and the force constant for RDC > ranged from 0.02 to 0.2, please find the picture1. but, if these two > RDC constraints are used together(scale factor for HACA RDC is used > 1), only for NH RDCs, the correlation became worse, CAHA RDC has > good correlation, and the Q values for all RDCs is around 0.4, > please find the picture2. How can I figure it out? >
Are you following eginput/gb1_rdc/refine.py? You must use proper scaling when mixing RDCs involving different nuclei. The function scale_toNH is usually used for this purpose. You may also need to first call rdcPotTools.correctGyromagneticSigns(). This is documented in https://nmr.cit.nih.gov/xplor-nih/doc/current/python/ref/rdcPotTools.html, and more explanation is available here: G.A. Bermejo and C.D. Schwieters, ``Protein Structure Elucidation from NMR Data with the Program Xplor-NIH,'' Methods Mol Biol. 1688, 311-340 (2018). best regards-- Charles ######################################################################## To unsubscribe from the XPLOR-NIH list, click the following link: http://list.nih.gov/cgi-bin/wa.exe?SUBED1=XPLOR-NIH&A=1
