Hi Jessica,
those "relatively decent R-values of 28%/31%" may not really indicate that your model is good. Take a look at http://strucbio.biologie.uni-konstanz.de/ccp4wiki/index.php/R-factors#what_kinds_of_problems_exist_with_these_indicators.3F . It cites Phil Evans and Garib Murshudov's paper http://journals.iucr.org/d/issues/2013/07/00/ba5190/index.html which shows that refining a perfect model against pure noise for a perfect twin will give you R-values of 29.1%. So I'd expect a good model to give much lower R-values against data that are better than noise.
In light of this, it is maybe not a surprise that the solvent B factors appear weird.
best wishes,
Kay
On Wed, 1 Jun 2016 20:48:41 +0000, Jessica Bruhn <[log in to unmask]> wrote:
>I was wondering if anyone had any explanations or tips for fixing things. This dataset was highly anisotropic, so I ellipsoidally truncated
> my data (2.6A, 3.5A and 3.7A in each direction). This dataset is also twinned with a 49% twin fraction. Despite all of that, I was able to build
> a relatively decent structure (28%/31%) that agrees well with the same protein in a different space group.
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