ABSTRACT
The regular structures assumed by the polypeptide serve the purpose of maintaining the total concentration of hydrogen bonds in the solution. The accessible surface areas tabulated are for the entire amino acid in a polypeptide, both side-chain and backbone segments. The neutral, but hydrophilic, amino acids glutamine and asparagine are straightforward examples of the effect of the hydrogen bonds formed with water in the unfolded polypeptide on the location of that amino acid in the folded polypeptide. In a protein, at any particular location in the amino acid sequence, the peptide bond is either trans in every molecule of that particular protein or cis in every molecule of that particular protein. The volume occupied by the atoms in a molecule of protein can be calculated by summing all of its individual atomic volumes defined by the van der Waals surface, and the actual volume of the molecule can be calculated from its partial specific volume and its molecular weight.
