pKa values of 30873399 Asp, Glu, His and Lys residues in 197146 soluble proteins.
pKa values of 3306058 Asp, Glu, His and Lys residues in 12602 transmembrane proteins.
pKa values of 2367154 Asp, Glu, His and Lys residues in 23337 protein-nucleic acid (PN), protein-protein (PP),and protein-ligand (PL_refined and PL_other) complexes.