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There was an update by E&H in 2001 in the International Tables Vol F.
There are a small number of modifications to the 1991 values in the
update as well as the addition of several conformational variabilities.
If I understand correctly, Refmac and Phenix use the 2001 values,
with the only conformational variability being some changes with
cis-peptide bonds.  Shelxl still uses E&H 1991.

Dale Tronrud

On 01/14/13 09:54, Ed Pozharski wrote:
> To what extent "modern" geometric restraints have been upgraded over
> original Engh&Huber?  And where I can find a consensus set of values
> (with variances)?
>
> For example, Fisher et al., Acta D68:800 discusses how histidine angles
> change with protonation, and refers to Engh&Huber when it says that
> ND1-CE1-NE2 goes from 111.2 to 107.5 when histidine acquires positive
> charge (Fig.6).  But angle table (Table 3) in original Engh&Huber from
> 1991 does not have any 107.5 value and seems to suggest that the numbers
> should rather be 111.7+-1.3 and 108.4+-1.0, respectively.
>
> I understand that these values are derived from structural databases and
> thus can be frequently updated.  Is there some resource where "most
> current" values would be listed?
>
> Cheers,
>
> Ed.
>