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Composition and structure of micellar calcium phosphate

Published online by Cambridge University Press:  01 June 2009

Carl Holt ,
Mathea J. J. M. van Kemenade ,
Lowell S. Nelson Jr ,
Lindsay Sawyer ,
John E. Harries ,
Raymond T. Bailey  and
David W. L. Hukins
Carl Holt
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK.
Mathea J. J. M. van Kemenade
Affiliation:
Van't Hoff Laboratory, University of Utrecht, 3584 CH, Utrecht, The Netherlands.
Lowell S. Nelson Jr
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK. Department of Medical Biophysics, University of Manchester, Manchester M13 9PT, UK.
Lindsay Sawyer
Affiliation:
Department of Biochemistry, University of Edinburgh, Edinburgh EH8 9XD, UK.
John E. Harries
Affiliation:
SERC Daresbury Laboratory, Warrington WA4 4AD, UK.
Raymond T. Bailey
Affiliation:
Department of Chemistry, University of Strathclyde, Glasgow Gl 1XL, UK
David W. L. Hukins
Affiliation:
Department of Medical Biophysics, University of Manchester, Manchester M13 9PT, UK.
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Summary

Micellar calcium phosphate has the chemical composition and physicochemical properties that are consistent with it being a complex of the phosphate centres of casein with an acidic amorphous calcium phosphate. Similar acidic amorphous calcium phosphates have been prepared in the laboratory and for these, as well as for micellar calcium phosphate, the most appropriate crystalline model compound from which the short-range structure may be derived is brushite, CaHPO4.2H2O. The predicted secondary structures around sites of phosphorylation in the Ca2+-sensitive caseins often comprise an α-hclix-loop-α-helix motif with the sites of phosphorylation in the loop region. This motif may be important in linking the colloidal calcium phosphate with casein in native casein micelles.

Type
Original Articles
Information
Journal of Dairy Research , Volume 56 , Issue 3: Special Issue: Proceedings of the Hannah Research Institute Casein Conference , May 1989 , pp. 411 - 416
Copyright
Copyright © Proprietors of Journal of Dairy Research 1989

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References

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