“…It follows that it is not the considerations concerning the secondary structure of protamine but rather the turns of the chain due to the presence of proline and glycine residues, and intramolecular interactions that shape the the tertiary structure of the molecule. (14,17,58) In contrast to the earlier view, it could be imagined that the conformation of oligoarginine stretches is relatively free and could be adjusted when bound to DNA. In short, it can be supposed that nonbasic amino acids determine the internal structure of the protamine molecule, whereas basic residues are responsible for the interaction with DNA.…”