pH-induced conformational transitions of bovine serum albumin investigated by ultraviolet derivative spectroscopy
导数紫外光谱法研究pH诱导牛血清蛋白构象变化

The fine absorption bands of three aromatic amino acid residues,Tryptophan (Trp),Tyrosine (Tyr),and Phenylalanine (Phe),of bovine serum albumin (BSA) were studied by ultraviolet second derivative spectroscopy.The conformation transitions of BSA at pH 2.3-12 were analyzed along with the absorption spectrum of the peptide bonds.It is observed that there exist obvious conformation transitions around the isoelectric point (pH 4.7) of BSA.The transitions are subtle between pH 5.7 and pH 10 but distinct in strong acidity(pH 2.3) and alkaline(pH 12) environments. Meanwhile,the concentration of BSA has certain effect on the conformation transition.