THE RELATION OF THE SECONDARY STRUCTURE OF PEPSIN 65 



2. Pepsin does not contain large helical regions but has essentially a 

 "random coil" configuration. This lack of any repeating or periodically 

 organized structure as a helical conformation represents, however, does 

 not exclude that each amino acid residue is in a specific or unique location. 



3. We should like to propose that in the case of pepsin hydrophobic 

 bonds play a considerable role in determining the secondary structure of 

 this enzyme. 



Acknowledgment 



This work was supported in part by Grant A2449 of the United States 

 Public Health Service. 



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