摘要:Thyroid hormone, thyroxine (T4) binding to glycosylated human serum albumin (G-HSA), and native human serum albumin (HSA) were studied as a function of pH using the fluorescence method. T4 binding affinity for G-HSA was remarkably reduced in an alkaline pH as compared with the native HSA. The thermodynamic parameters for binding are estimated at pH 7.5 : (a) for G-HSA, ΔG=-8.50±0.04 kcal mol-1 (30°C), ΔH=-5.2 kcal mol-1, ΔS=+11 e. u. ; (b) for HSA, ΔG=-8.89±0.04 kcal mol-1 (30°C), ΔH=-3.5 kcal mol-1, ΔS=+18 e. u. These results suggest that the glycosylation of HSA causes a variation in the electrostatic interaction between T4 and HSA.
关键词:thyroid hormone;thyroxine;hormone binding;human serum albumin;glycosylated human serum albumin;fluorescence