Ceruloplasmin

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ceruloplasmin

[sə¦rül·ō¦plaz·mən]
(biochemistry)
The copper-binding serum protein in human blood.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Ceruloplasmin

 

a copper-containing protein of the α2-globulin fraction of blood plasma. It was first discovered and isolated by the Swedish scientists C. Holmberg and C. Laurell in 1948. Its content in human plasma is 0.2–0.3 mg/ml. Ceruloplas-min, which has a molecular weight of 130,000, is bound to 60–99 percent of all the plasma copper ions. Its two molecular forms differ in the number of carbohydrate chains, which consist of galactose, mannose, fucose, N-acetylglucosamine, and sialic-acid residues. Ceruloplasmin has some catalytic activity, oxidizing polyamines, polyphenols, and ascorbic acid (vitamin C). It also takes part in hematopoiesis and the transport of copper to sites where other copper-containing proteins, such as cytochromoe oxidases, are synthesized. In addition, it apparently participates in the regulation of the level of biogenic amines.

There exist genetically determined variants of ceruloplasmin caused by the presence of mutant alleles. The level of ceruloplas-min in blood serum increases nonspecifically during pregnancy, infections, anemias, and malignancies but decreases during the Wilson-Konovalov disease and some other diseases.

N. N. CHERNOV

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Automated measurement of serum ferroxidase activity.
Bergamini et al., "PON-1 and ferroxidase activities in older patients with mild cognitive impairment, late onset Alzheimer's disease or vascular dementia," Clinical Chemistry and Laboratory Medicine, vol.
After export, it is reoxidized from Fe(II) to Fe(III) by the membrane-bound ferroxidase hephaestin and possibly by intestinal ceruloplasmin [38].
di Patti et al., "Ferroxidase activity is required for the stability of cell surface ferroportin in cells expressing GPI-ceruloplasmin," The EMBO Journal, vol.
Wielkoszynski, "Raspberry seed extract effect on the ferroxidase activity of ceruloplasmin isolated from plasma," Food Chemistry, vol.
The expression of several genes involved in iron metabolism including lactotransferrin, ceruloplasmin ferroxidase, lipocalin 2 and ferroportin [12] upregulate during uterine growth and differentiation.
Whole cell protein was extracted and protein concentration was determined by Lowry method to proceed for ferroxidase assay by using a method as previously described.
Examples of proteins found in higher organisms include hemoglobin, cytochrome P450 and catalase .Most of the iron ([Fe.sup.2+]) is oxidized to ([Fe.sup.3+]) by the ferroxidase activity of ceruloplasmin (Cp) and /or spontaneous oxidization and then bind to transferrin and to be acquired by the cells.
In human plasma, more than 95% of total copper is associated with ceruloplasmin (Cp), copper carrier and a ferroxidase that is also responsible for iron metabolism, while less than 5% of copper ions are associated with other proteins (Heilman and Gitlin 2002).
Association of haptoglobin phenotypes with ceruloplasmin ferroxidase activity in AY-thalassemia major.