Ceruloplasmin and other copper binding components of blood plasma and their functions: an update

Abstract

We know that blood plasma contains many proteins and also other components that bind copper. The largest contributor to copper in the plasma is ceruloplasmin, which accounts for 40-70 percent. Apart from ceruloplasmin and albumin, most of these components have not been studied extensively, and even for ceruloplasmin and albumin, much remains to be discovered. New components with new functions, and new functions of known components are emerging, some warranting reconsideration of earlier findings. The author's laboratory has been actively involved in research on this topic. This review summarizes and updates our knowledge of the nature and functions of ceruloplasmin and the other known and emerging copper-containing molecules (principally proteins) in this fluid, to better understand how they contribute to copper homeostasis and consider their potential significance to health and disease.

Role of Calprotectin in Withholding Zinc and Copper from Candida albicans

“…Typical laboratory growth media, whether they are chemically defined or more complex (e.g., YPD), cannot readily replicate the metal environment of an animal host, although animal serum is expected to contain many of the natural sources. Much of the Cu in circulatory serum is transported via the globular proteins ceruloplasmin, transcuprein, and albumin (68). Interestingly, albumin, with an affinity for Cu K d of Ն10 Ϫ11 M (69, 70), can directly bind C. albicans and serve as a nitrogen source for the fungus (71,72) and may very well serve as a source of metals.…”

Speciation of Metal Complexes of Medicinal Interest: Relationship between Solution Equilibria and Pharmaceutical Properties

“…α2-macroglobulin and transcuprein also bind some copper in serum. They have high affinity binding sites for copper, higher than in HSA [27]. They guarantee fast exchangeable copper pool for the tissues [27,29].…”

“…Its serum level is 1.5-2.7 µM and 40-70% of the copper is bound to this protein [26,27]. 6-7 Cu/protein are tightly bound and buried in the ceruloplasmin in different environments mostly in non-exchangeable copper pool [27][28]. 20% of serum Cu(II) is bound to HSA almost exclusively at the specific ATCUN binding site [26,27,29].…”

“…6-7 Cu/protein are tightly bound and buried in the ceruloplasmin in different environments mostly in non-exchangeable copper pool [27][28]. 20% of serum Cu(II) is bound to HSA almost exclusively at the specific ATCUN binding site [26,27,29]. The albumin bound copper means the exchangeable pool, which can deliver the metal ion to most of the cells.…”

“…The largest part of the copper is bound in the oxidation state of two in ceruloplasmin. Its serum level is 1.5-2.7 µM and 40-70% of the copper is bound to this protein [26,27]. 6-7 Cu/protein are tightly bound and buried in the ceruloplasmin in different environments mostly in non-exchangeable copper pool [27][28].…”