Research of binding reaction mechanism for adenosine in traditional Chinese medicine with serum albumin / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the binding mechanism between adenosine (Ade), an active component of some traditional Chinese medicines, and human serum albumin (USA). METHODS: The binding constant K and binding sites n were obtained by using fluorescence and UV absorption spectroscopy. In addition, the reaction mechanism was discussed. The energy transfer parameters of the reaction system were determined as was the effect of Ade on HSA's conformation on the basis of Fōrster theory. The binding reaction model of HSA with Ade was constructed through molecular simulation and compared with the experiment results. RESULTS: Ade could bind HSA to form static complex. The binding constant (K) was 1.39 × 10 L3 · mol-1 and binding sites (n) was 0.94. The binding distance r between Ade and HSA was very short, which indicated the phenomenon of energy transfer. Ade changed the hydrophobic environment of the binding domain in HSA and caused certain changes for micro area conformation. Computer molecular docking technology showed that the interactions of Ade with HSA were mainly hydrophobic interaction and hydrogen bonding between purine ring of Ade and amino acid residues of HSA. CONCLUSION: The theoretical calculation and experiment results were in consistency, which provided certain reference for the study of pharmacological mechanism for the active ingredient of some traditional Chinese medicines, adenosine. Copyright 2012 by the Chinese Pharmaceutical Association.