Ramachandran plot torsion angles

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MrGenetic
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Can torsion angles were affected by repulsive effect of aminoacid interactions between side chains?
Can torsion angles were affected by hydrophilic or hydrophilic interactions between side chains?
I know that protein levels were affected by them but torsion angles is suspicious for me
 
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MrGenetic said:
Can torsion angles were affected by repulsive effect of aminoacid interactions between side chains?
Can torsion angles were affected by hydrophilic or hydrophilic interactions between side chains?
Yes, of course, they are more affected with stronger interactions.
On a single chain there are more interaction between the polar or non polar groups.
Two single chain that are close can interact, and exercise a repulsive effect on each other, if there are polar groups.

You wrote twice hydrophilic, but I suppose you wanted to say hydrophobic or hydrophilic.
Anyway, an aminoacid, in a solution can have different reactions, it depend on how the solution is.
In any case, they solution can affect the torsion angles.
 
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The plot is a way to visualize energetically allowed regions for backbone dihedral angles ψ against φ of amino acid residues in protein structure. The stability of some sidechain dihedral angles are affected by the values φ and ψ. Not all.

From wikipedia
When the two intersecting planes are described in terms of Cartesian coordinates by the two equations:
643b42eaa74a2227e2553755864d2b99daf5b9b3

602aef36c9617f4947bad06846f6cfcd1784b311

the dihedral angle, φ between them is given by:

$$cos ⁡ φ = | a 1 a 2 + b 1 b 2 + c 1 c 2 | a 1 2 + b 1 2 + c 1 2 a 2 2 + b 2 2 + c 2 2 . {\displaystyle \cos \varphi ={\frac {\left\vert a_{1}a_{2}+b_{1}b_{2}+c_{1}c_{2}\right\vert }{{\sqrt {a_{1}^{2}+b_{1}^{2}+c_{1}^{2}}}{\sqrt {a_{2}^{2}+b_{2}^{2}+c_{2}^{2}}}}}.} $$

Here is a link about the ability to predict those dihedral angles and a library of functions to do so. Best I can do:
http://www.sciencedirect.com/science/article/pii/S0022283683711708?via=ihub