Spectral and kinetic studies on the binding of trithiomolybdate to bovine and canine serum albumin in vitro: the interaction with copper.
Spectral studies showed that copper and trithiomolybdate participated in a three-way interaction with bovine and canine serum albumin. The interaction with the proteins was affected by increased pH and ionic strength. Kinetic studies of binding equilibria indicated that [35S] trithiomolybdate bound to both albumins at a single site. The affinity of the site, but not the capacity of the protein, was increased by copper. It was concluded that the site was distinct from the N-terminal copper (and nickel) binding site, which is present on BSA but absent from CSA. Whether or not the N-terminal site has a role in copper transport is discussed. Reversible thiomolybdate-copper-protein interactions of this type may play a fundamental role in the pathogenesis of Mo-induced syndromes, since as the normal binding patterns are perturbed the interprotein equilibria are altered and the copper distribution patterns are modified.
Woods
M
M
Biochemistry Department, Trinity College, Dublin, Ireland.
Mason
J
J
D000818:Animals; D002417:Cattle; D003300:Copper / Q000097:blood*; D004285:Dogs; D007700:Kinetics; D008982:Molybdenum / Q000097:blood*; D011485:Protein Binding; D012709:Serum Albumin / Q000378:metabolism*; D013045:Species Specificity; D013053:Spectrophotometry
D012709:Serum Albumin; C034540:trithiomolybdic acid; D003300:Copper; D008982:Molybdenum