Answer:
Based on the information provided, we can predict that the active site of the HIV protease enzyme is lined with negatively charged amino acid residues. The negatively charged active site of the enzyme is likely to form ionic bonds with the positively charged or polar regions of the substrate molecule, which would allow the substrate molecule to bind to the enzyme's active site.
Ionic bonds are formed between two oppositely charged ions, in this case, between the negatively charged active site of the enzyme and the positively charged or polar regions of the substrate molecule. Ionic bonds are relatively strong and can contribute to the stability of the enzyme-substrate complex. Other types of bonds that may also form between the enzyme and substrate include hydrogen bonds, hydrophobic interactions, and van der Waals interactions, depending on the specific amino acid residues present in the active site and the chemical properties of the substrate.