Resonance energy transfer, pH-induced folded states and the molecular interaction of human serum albumin and icariin.

摘要: Icariin is a flavonol glycoside with wide range of pharmacological and biological activities. The functions flavonoid compounds mainly originate from their binding to proteins. mode interaction icariin human serum albumin (HSA) has been characterized by fluorescence spectroscopy far- near-UV circular dichroism (CD) under different pH conditions. Fluorescence quenching studies showed that the affinity HSA in buffer solution at values is: Ka (pH 4.5) > 3.5) 9.0) 7.0). Red-edge excitation shift (REES) revealed had an obvious effect on mobility tryptophan microenvironment addition made REES more distinct. static mechanism number sites (n ≈ 1) were obtained data three temperatures (298, 304 310 K). Both ∆H0 < 0 ∆Ѕ0 suggested hydrogen bonding van der Waal's major driving forces mechanism, this was also confirmed molecular simulation results. distance r between donor acceptor (icariin) calculated based Forster non-radiation energy transfer theory. We found little impact icariin. Far- CD further indicated influence complexation process alteration protein conformation upon binding. Copyright © 2015 John Wiley & Sons, Ltd.