A review of the biology of calcium phosphate sequestration with special reference to milk

Lenton, S., Nylander, T., Teixeira, S. C.M. and Holt, C. (2015) A review of the biology of calcium phosphate sequestration with special reference to milk. Dairy Science and Technology, 95(1), pp. 3-14. (doi: 10.1007/s13594-014-0177-2)

Abstract

In milk, a stable fluid is formed in which sequestered nanoclusters of calcium phosphate are substructures in casein micelles. As a result, calcium and phosphate concentrations in milk can be far in excess of their solubility. Variations of calcium, phosphate and casein concentrations in milks, both within and among species, are mainly due to the formation of the nanocluster complexes. Caseins evolved from tooth and bone proteins well before the evolution of lactation. It has therefore been suggested that the role of caseins in milk is an adaptation of an antecedent function in the control of some aspect of biomineralisation. There is new evidence that nanocluster-type complexes are also present in blood serum and, by implication, in many other closely related biofluids. Because such fluids are stable but nevertheless supersaturated with respect to the bone and tooth mineral hydroxyapatite, they allow soft and mineralised tissues to co-exist in the same organism with relative ease. An appreciable concentration of nanocluster complexes exists in fresh saliva. Such saliva may stabilise tooth mineral and help to repair demineralised lesions. In the extracellular matrix of bone, nanocluster complexes may be involved in directing the amorphous calcium phosphate to intrafibrillar spaces in collagen where they can mature into oriented apatite crystals. Thus, evidence is accumulating that calcium phosphate sequestration by phosphopeptides to form equilibrium complexes, first observed in milk, is more generally important in the control of physiological calcification.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Holt, Dr Carl
• Authors: Lenton, S., Nylander, T., Teixeira, S. C.M., and Holt, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Dairy Science and Technology
• Publisher: Springer Verlag
• ISSN: 1958-5586
• ISSN (Online): 1958-5594
• Copyright Holders: Copyright © 2014 The Authors
• First Published: First published in Dairy Science and Technology 95(1):3-14
• Publisher Policy: Reproduced under a Creative Commons License