Binding and the nature of Cu(II) ion interaction with nucleosomes

Abstract

The energetics of Cu (II) ion binding to mononucleosomes from C3HA mice liver and ascitic hepatoma 22A cells was determined from their binding isotherms by equilibrium dialysis and pulse high frequency inductively coupled plasma atomic emission spectroscopy. Anticooperative binding of copper ions with normal and tumor mononucleosomes were observed under various NaCl concentrations (0.002; 0.02; 0.2 M). The binding constants of Cu(II) ion with normal mononucleosomes in 0.002, 0.02, 0.2 M NaCl are 6.10×10 4,5.22×10 4,4.31×10 4 respectively. The binding constants of Cu(II) ion with tumor mononucleosomes in 0.002, 0.02, 0.2 M NaCl are 6.68×10 4,6.12×10 4,4.82×10 4 respectively.