The glutamic acid and aspartic acid residues give the ring its hydrophilic character, as well as its negative charge. Conversely, the valine residue extends down, facing the fatty acid chain, to form a major hydrophobic domain.
The amino acid composition of the ring influences its overall charge and hydrophobicity. Glutamic acid and aspartic acid are negatively charged, while valine's hydrophobic character contributes to a distinct region within the structure.