Three given polypeptides $(\mathrm{P},\mathrm{Q}$ and $\mathrm{R})$, of same size and same $\mathrm{pI}(7.2)$, have a single aspartic acid in each of them. In polypeptide $\mathrm{P}$, the aspartic acid residue is on the surface. In polypeptide $\mathrm{Q}$, it is surrounded by negatively charged residues, whereas in polypeptide $\mathrm{R}$ it is deeply buried in a hydrophobic core. $\mathrm{pKa}$ of the side chain carboxylate of free (in solution) aspartic acid is $3.65$. The polypeptides are in a buffer of $\mathrm{pH}$ $7.4$. The change in $\mathrm{pKa}$ of the aspartic acid side chain carboxylate in the polypeptides $\mathrm{P}, \mathrm{Q}$ and $\mathrm{R}$ is likely to