Hi, I am doing a RDC-refinement of an RNA molecule. I predicted the axial component and the rhombicity of the alignment tensor by relating to the gyration tensor. [Wu, B.; Petersen, M.;Girard, F.; Tessari, M.;Wijmenga S.S. (2006): J.Biomol. NMR, 35, pp. 103-115]
In Xplor I incorporated these values: sani coef 0.0 -51.72 0.14 (first number is addition (a0), second number anisotropy, and third rhombicity) In my refinement script I have a floating alignment tensor. After refinement I do a backcalculation, and see a correlation between the experimental and backcalculated values of 0.997 ! If I look at the structures, I see the Ayy is along the longest axis of the molecule (mine is 'rod'-shaped). What happens? And how can I fix this ? Azz should be along the longest axis of the molecule. And the backcalculation should also see this 'error'. Greetings, Ramon -- R.M. van der Werf E-mail: R.vanderWerf at nmr.ru.nl Radboud university of Nijmegen Dept. Biophysical Chemistry (NMR)
