Potentiometric determination of formation constants of copper(II)/bile acid/peptide in aqueous solution.
A potentiometric method was used to study the equilibria in aqueous solution for the systems copper(II)/bile acid salt/peptide [bile acid salt-sodium cholate or glycocholate; and peptide-glutamic acid (glutamate), glutamine or glutamylglutamic acid], specifically to assess cooperative binding between small peptides and bile acids in the presence of copper(II). The results obtained suggest large cooperativity in formation of ternary complexes with amino acids when they are coordinated to copper(II) as bidentate ligands.
de Castro
B
B
CEQUP/Departamento de Química, Faculdade de Ciências, Universidade do Porto, Portugal.
Lima
J L
JL
Reis
S
S
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D001647:Bile Acids and Salts / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D008024:Ligands; D008823:Micelles; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D011199:Potentiometry; D011485:Protein Binding; D012996:Solutions
D000596:Amino Acids; D001647:Bile Acids and Salts; D007202:Indicators and Reagents; D008024:Ligands; D008823:Micelles; D010455:Peptides; D012996:Solutions; D003300:Copper