Stereochemical parameters

The table below lists some the stereochemical parameters of Morris et al. (1992), derived from high-resolution protein structures.
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Stereochemical parameter     |    Mean value   |    St. dev.
--------------------------------------------------------------
                             |                 |                 
Phi-psi in most favoured     |                 |                 
regions of Ramachandran plot |       >90%      |                 
                             |                 |                 
Chi1 dihedral angle:         |                 |                 
   gauche minus              |    64.1 degrees |  15.7 degrees
   trans                     |   183.6 degrees |  16.8 degrees
   gauce plus                |   -66.7 degrees |  15.0 degrees
                             |                 |                 
Chi2 dihedral angle          |   177.4 degrees |  18.5 degrees
                             |                 |                 
Proline phi torsion angle    |   -65.4 degrees |  11.2 degrees
                             |                 |                 
Helix phi torsion angle      |   -65.3 degrees |  11.9 degrees
Helix psi torsion angle      |   -39.4 degrees |  11.3 degrees
                             |                 |                 
Chi3 (S-S bridge):           |                 |                 
   right-handed              |    96.8 degrees |  14.8 degrees
   left-handed               |   -85.8 degrees |  10.7 degrees
                             |                 |                 
Disulphide bond separation   |     2.0A        |   0.1A
                             |                 |                 
Omega dihedral angle         |   180.0 degrees |   5.8 degrees
                             |                 |                 
Main-chain hydrogen          |                 |                 
bond energy (kcal/mol)*      |    -2.03        |   0.75            
                             |                 |                 
C-alpha chirality: zeta      |                 |                 
`virtual' torsion angle      |    33.9 degrees |   3.5 degrees
(Calpha-N-C-Cbeta            |                 |                 
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* Evaluated using the Kabsch & Sander (1983) method.