Effects of selected two noble metal ions in medicine on the structure and activity of bovine serum albumin: A multi-spectral studies

In the present study, the toxic influence of two metallic ions on serum albumin was studied by using fluorescence, UV/vis, circular dichroism spectroscopy, and molecular docking , with the aim of delineating the effects of Pt(II) and Au(III) ions on the secondary and tertiary structure , the transportation function, the thermal stability, and the esterase-like activity of bovine serum albumin (BSA). The conformational change occurring in protein structure was monitored by CD and fluorescence spectroscopy . Pt(II) and Au(III) could react with some functional groups of BSA, making the secondary structure change and increasing the microenvironment around Tyr residues of BSA. The content of α-helix decreased remarkably and the contents of β-sheet, and random coil increased with increasing concentration of Pt(II) or Au(III) ion. Compared with Pt(II) ion, Au(III) ion is more likely to damage the tertiary structure of BSA and a higher number of Tyr residues are affected in Au(III)-BSA system. The fluorescence and UV/vis spectral results indicated the formation of Pt(II)-BSA and Au(III)-BSA complexes. In addition, metal ion binding decreased the ANS binding ability, the reversibility of the thermal unfolding process and the esterase-like activity of BSA. Therefore, this paper is expected to improve the toxicity evaluation mechanism of platinum and gold ions.