Proteopedia:Featured EDU/1
From Proteopedia
| Tutorial: The Ramachandran principle, phi (φ) and psi (ψ) angles in proteins | 
| Eric Martz | 
| 
 The Ramachandran Principle says that alpha helices, beta strands, and turns are the most likely conformations for a polypeptide chain to adopt, because most other conformations are impossible due to steric collisions between atoms. Check Show Clashes to see where non-bonded atoms are overlapping, and thus in physically impossible positions. (This model simulation allows two atoms to overlap, unlike real atoms.)  | 

