On Tue, 2012-01-10 at 18:30 +0000, Theresa H. Hsu wrote:
> Thank you for the interesting replies so far.
>
> Please let me ask a related question - at what resolution should we stop
> efforts to get better diffracting crystals? Are there *biological* questions
> that a model with 1.8-2.0 A resolution (with combination of complementary
> methods like spectroscopy) cannot answer than a model with < 1 A?
>
> Theresa
Most of the time one does not need ultrahigh resolution to answer a
"biological question". Some examples of the opposite:
1. Anisotropic B-factors may provide some insight regarding
directionality of the protein dynamics
2. Unrestrained refinement at ultrahigh resolution allows to delineate
protonation states (e.g. by looking at the covalent bonds, sometimes you
can convince yourself that the density corresponding to the hydrogen is
actually present)
3. Alternate conformations may be clarified.
4. Improved precision allows to correlate changes in hydrogen/metal
bonds to enzymatic activity.
What, in broad terms, is your "biological question"? Knowing that would
allow for a more specific answer.
Cheers,
Ed.
--
"Hurry up before we all come back to our senses!"
Julian, King of Lemurs
