Dear Francesco,
are you certain that nucleotide are properly managed by the software
that you use for refinement ?
And at this resolution , you should be able to see ions and water in
relation with DNA are they already modeled ? More about the refinement
strategy itself did you use TLS ?
I ask more question than I give answer (sorry), but it's to better
understand the problem.
Nicolas
On 22/08/2016 11:56, Francesco Papi wrote:
> 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
|