I think Goodhart's Law applies here (see the Wikipedia page):
When a measure becomes a target, it ceases to be a good measure.

From memory I believe Randy Read and George Sheldrick have commented that
Ramachandran plots are a good measure of structure quality, and therefore should
not be used explicitly at the modelling stage. Some residues may be difficult
if they have more than one backbone conformation or are just mobile, but
expressly holding them in favoured regions of the Ramachandran plot is not a good
idea. The most interesting proteins are of course enzymes, and the Ramachandran
outliers are often among the most interesting active site residues. So you may be trying
to eliminate something which is actually more important than a low Rfactor.

The idea of limiting data use may seem counter-intuitive, but to take another
example from economics, John Cowperthwaite was in charge of Hong Kong's
financial affairs in the 1960s. He attributed the success of the economy under his
tenure to his adamant refusal to collect any economic data whatsoever!


On Feb 26, 2015, at 2:08 AM, Michael Murphy wrote:

> Does anyone know of a way to adjust Ramachandran angles so that they fall within the preferred range? Either in Coot or possibly some online server? I have been trying to do it manually without much success, I was wondering whether there might another way to do it. -Thanks