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Hi Smith, 2-3 A is not atomic resolution, so you cannot meaningfully measure distances between individual atoms in your model at this resolution, I think (I guess it is safer to say that you can measure these distances, technically, but their meaning is not going to be straightforward to interpret). Pavel On 7/21/15 20:10, Smith Liu wrote:
Dear Pavel,
Related to Joel's question, suppose the resolution is about 2-3 A, and I have added H (should be modelled "H")for the refinement. If I want to measure the H-bond length between the NE2 and H of OH of Tyr, I need to measure the distance between NE2 and the "modelled H" of OH of Tyr. Is this "modelled H" position reliable for the length measurement of the H-bond?
Best regards.
Smith
At 2015-07-22 10:04:39, "Pavel Afonine"
wrote: Hi Joel,
as was suggested main.nqh_flips=False should disable this.
However I'm puzzled about this. NQH flips functionality is designed to flip these residues such that the clashes are minimized and plausible H-bonding is achieved. So I wonder why it is not working in your case?
Would it be possible to send me input files (off list) so that I can reproduce this and investigate. Also please indicate HIS in question.
Thanks, Pavel
On 7/21/15 02:07, Joel Tyndall wrote:
Hi all,
We are trying to optimise a histidine interaction where NE2 would ideally make a hydrogen bond with an adjacent tyrosine hydroxyl. The starting point contains the hydrogen bond. However upon refinement the ring flips (chi2 x 180 degrees) to place the CE1 adjacent to the tyrosine hydroxyl.
Is it possible to stop this as I see no reason why phenix.refine would want to do this
Regards
Joel