Hydrophobic scale: a second parameter to elucidating various specific ligand-protein interactions

In the sequence Fourier analysis (SFA) of specific interactions such as those between fibroblast growth factors (FGFs)/FGF receptors (FGFRs), bone morphogenetic proteins (BMPs)/BMP receptors (BMPRs), or tumor repressor protein p53/mouse double minute 2 homolog (MDM2), the characteristic frequency peak(s) could be observed with the hydrophobic scale for 20 amino acids as well as 4 nucleotides as the physicochemical parameter, but not successfully with the absolute electronegativity scale. This result implies that these two independent scales should be appropriately selected in various specific ligand-protein interactions, though the critical difference has to be determined.