Final answer:
Hydrogen bonding is the most important interaction in enhancing the solubility of macromolecules in water.
Step-by-step explanation:
The most important interaction in enhancing the solubility of macromolecules in water is hydrogen bonding. Water molecules have strong intermolecular forces of hydrogen bonding, and this allows them to attract and surround macromolecules with exposed polar chemical groups, such as proteins and nucleic acids. Hydrogen bonding between water molecules and the polar groups of macromolecules helps to dissolve them in water.