Comparison of the Effects on Bovine Serum Albumin Induced by Different Forms of Vanadium.

Various forms of vanadium coexist in vivo, and the behavior mechanism is different. An investigation of the separate and simultaneous binding of three vanadium forms with bovine serum albumin (BSA) was performed. VO(acac)2/NaVO3/VOSO4 bound to site I of BSA, and their binding constants were 4.26 × 105, 9.18 × 103, and 4.31 × 102 L mol-1 at 298 K, respectively. VO(acac)2 had the strongest binding ability to BSA and had the most influence on the secondary structure of BSA and the microenvironment of around amino acid residues. The effect of NaVO3 and VOSO4 coexistence on the binding of VO(acac)2 to BSA was therefore further investigated. Both NaVO3 and VOSO4 had an effect on the binding of VO(acac)2 and BSA, with NaVO3 having the most noticeable effect. NaVO3 interfered with the binding process of VO(acac)2 and BSA, increased the binding constant, and changed the binding forces between them. Competition and allosteric effect may be responsible for the change of binding process between VO(acac)2 and BSA in the presence of NaVO3/VOSO4.