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The Sub‐picomolar Cu 2+ Dissociation Constant of Human Serum Albumin
Author(s) -
BossakAhmad Karolina,
Frączyk Tomasz,
Bal Wojciech,
Drew Simon C.
Publication year - 2020
Publication title -
chembiochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 126
eISSN - 1439-7633
pISSN - 1439-4227
DOI - 10.1002/cbic.201900435
Subject(s) - chemistry , tripeptide , potentiometric titration , human serum albumin , circular dichroism , dissociation constant , copper , divalent , titration , electron paramagnetic resonance , ligand (biochemistry) , crystallography , inorganic chemistry , nuclear magnetic resonance , chromatography , biochemistry , peptide , organic chemistry , receptor , electrode , physics
The apparent affinity of human serum albumin (HSA) for divalent copper has long been the subject of great interest, due to its presumed role as the major Cu 2+ ‐binding ligand in blood and cerebrospinal fluid. Using a combination of electronic absorption, circular dichroism and room‐temperature electron paramagnetic resonance spectroscopies, together with potentiometric titrations, we competed the tripeptide GGH against HSA to reveal a conditional binding constant of log c K CuCu ( HSA )=13.02±0.05 at pH 7.4. This rigorously determined value of the Cu 2+ affinity has important implications for understanding the extracellular distribution of copper.