The Sub-picomolar Cu2+ Dissociation Constant of Human Serum Albumin
The Sub-picomolar Cu2+ Dissociation Constant of Human Serum Albumin
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DOI：
10.1002/cbic.201900435
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发表时间：
2019-10-29
期刊：
影响因子：
3.2
通讯作者：
Drew, Simon C.
中科院分区：
文献类型：
--
作者：
Bossak-Ahmad, Karolina;Fraczyk, Tomasz;Drew, Simon C.
人血清白蛋白 (HSA) 对二价铜的表观亲和力长期以来一直是人们极大兴趣的主题，因为人们推测它是血液和脑脊液中主要的 Cu2+ 结合配体。结合使用电子吸收、圆二色性和室温电子顺磁共振光谱，以及电位滴定，我们将三肽 GGH 与 HSA 进行竞争，揭示了在 pH 7.4 下 log KCuCu(HSA)=13.02 +/- 0.05 的条件结合常数。这种严格确定的 Cu2+ 亲和力值对于了解铜的细胞外分布具有重要意义。
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 Cu2+-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 KCuCu(HSA)=13.02 +/- 0.05 at pH 7.4. This rigorously determined value of the Cu2+ affinity has important implications for understanding the extracellular distribution of copper.