Dear crystallographers,
I am working on a ligand-DNA structure. Although the structure seems
completed and well localized in the electronic density maps, Rfree is
stuck around 32%. Data are good up to 1.5 angstrom resolution. Pointless
and ctruncate analyses haven't shown neither twinning nor NCS. I have
checked again the space group and it seems ok (Zanuda). I have tried to
run some EDM methods but R and R free don't change significantly. To be
honest, I do not understrand where the problem is. Do you have any
suggestions?
Thank you
Best regards
Francesco Papi
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