Macromolecular recognition: discrimination between human and bovine serum albumins by cyclodextrins.

The interactions of cyclodextrins (CDs) with human serum albumin (HSA) and bovine serum albumin (BSA) were investigated by two-dimensional nuclear Overhauser effect spectroscopy (2D NOESY), steady state fluorescence, isothermal titration calorimetry, and circular dichroism spectroscopy. 2D NOESY indicates that α-CD and β-CD, but not γ-CD, interact with the aromatic amino acid residues on HSA. On the other hand, the 2D NOESY signals between CDs and BSA are not significantly correlated. Hence, CDs can discriminate the subtle protein structural differences of HSA and BSA.