Interaction Between Bovine Serum Albumin And Two Kinds Of Antidiabetic Drugs And Role Of H143 In The Rusticyanin

The serum albumin is the most abundant protein in plasma, which possesses endogenous metabolites and medicinal molecules in storage and transportation and can be combined with a variety of endogenous and exogenous molecules by forming complexes to achieve the physiological functions in plasma. The study of the interaction between Antidiabetic drugs and serum albumin is important reference value for pharmacokinetics, pharmaceutics and clinic medicine. Rusticyanin is a principal component in the iron respiratory electron transport chain of Acidithiobacillus ferrooxidans.To study the property of Rusticyanin(RUS) could provide a basis for the research of copper protein family like Ceruloplasmin.The reaction mechanism of antidiabetic drugs(PIO and MET) with protein were studied by fluorescence spectroscopy(FS) and UV-vis spectroscopy(UV) and interaction of molecules with bovine serum albumin(BSA) were investigated.The experimental results showed the interaction information of antidiabetic drugs with BSA,is useful for reforming drug structure and synthesizing new drugs.Role of His143 in the electron transfer of RUS was studied by UV,molecular modeling and site-directed mutagenesis.The main process and achievements of this paper as follow:1.The interaction of PIO with BSA were studied by fluorescence and UV-vis spectroscopy.The quenching mechanism of fluorescence of BSA by PIO was investigated,the result showed the quenching mechanism was dynamic quenching.The binding constant K and binding sites number n were measured by fluorescence quenching method.Thermodynamic parameters obtained from measured data(?G??H??S) and principal binding and principal binding was hydrophobic force.2.The interactions of MET with BSA had been investigated with the use of spectrofluorimetry.The quenching mechanism of fluorescence of BSA with MET was found to be dynamic quenching.The binding constant K and binding sites number n were measured by fluorescence quenching method.The principal driving forces were hydrogen bond and van der Waals force between MET and BSA,and the Autodock verified the result further.3.The property of His143 of RUS was studied with the use of UV-vis spectroscopy and molecular modeling.His143 was found to be a important residue for the electron transfer in RUS, according to site-directed mutagenesis, SDS-PAGEanalysis,UV-scanning results.Molecular structure modeling for RUS and the mutant His143 G protein revealed that the imidazole group of His143 formed a hydrophobic barrier to protect the copper from exposing to solvent.