Schiffer-Edmundson helical wheel

Schiffer, M., and Edmundson, A, B. Use of helical wheels to represent the structures of proteins and to identify segments with helical potential. Biophys. J. 7, 121-135 (1967). 

Schiffer and Edmundson observed that nonpolar residues within a helical i on of a protein show a significant tendency to form nonpolar clusters. This finding vras illustrated by means of a so-called helical wheel (Fig. 5). 

Approaches considering stereochemical aspects are the wheel representation of helical regions by Schiffer and Edmundson and a secondary structure prediction heme... 

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