Hello Sun,
Roman Hillig and I refined a mixture of ADP+PO4 and ATP in the active site of ARL2 - it is enough to exclude all contacts of the superposing ligands and let the occupancies refine. The protocol we followed is described in:
Hanzal-Bayer M, Renault L, Roversi P, Wittinghofer A, Hillig RC.
Free in PMC
The complex of Arl2-GTP and PDE delta: from structure to function.
EMBO J. 2002 May 1;21(9):2095-106.
Best of luck!
Pietro
<[log in to unmask]> writes:
> Hello everyone,
>
> I have a structure of intermediate state in which about half amount of ATP decomposed to AMP and pyrophosphate. The ATP and AMP + pyrophosphate have little difference in conformation, sharing the same electron density.
>
> I just gave them different residue ID and did the TLS and restrained refinement in CCP4i. It is hard to tell from the R-factor because they are only a very small part of the whole structure. Can anyone tell whether it is the correct way to do?
>
> Any suggestions are greatly appreciated.
>
> Thank you very much!
>
> Sincerely,
>
> Sun Tang
>
>
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