Interaction between cytochrome c and DNA: conformation, peroxidase activity and molecular dynamics simulation

A mixed system of cytochrome c (Cyt c, a typical hemoprotein) and DNA was constructed and the interaction between Cyt c and DNA were analyzed by experiment and molecular dynamics (MD) simulation methods, respectively. On the one hand, the experimental results showed: 1. The peroxidase activity of the mixed system was significantly enhanced relative to the Cyt c in 50 mM phosphate buffer solution at 25ºC. 2. UV-Vis spectra study found that, compared with the Cyt c solution, the absorbance of the Cyt c-DNA mixed system increased significantly at 280 nm, while the absorbance decreased at 405 nm, indicating that the overall structure of Cyt c in the mixed system became loose, and the structure around heme group became more compact. 3. Circular Dichroism (CD) studies showed that there was a weak interaction between DNA and Cyt c in the mixed system, which had little effects on the secondary structures of Cyt c. On the other hand, MD simulation results showed: 1. DNA and Cyt c were combined b...