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A glyco-phosphoprotein in human milk

Published online by Cambridge University Press:  01 June 2009

Norihiro Azuma
Affiliation:
Department of Agricultural Chemistry, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan
Kunio Yamauchi
Affiliation:
Department of Agricultural Chemistry, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan

Summary

A highly glycosylated phosphoprotein (HGPP) was isolated from a human casein fraction by reversed-phase high-performance liquid chromatography. This component contained carbohydrates to ∼ 38·2% (w/w) and phosphorus to ∼ 1·6% (w/w). The molecular weight of this HGPP as estimated by sodium dodecyl sulphate–polyacrylamide gel electrophoresis ∼ 41000. Ultracentrifugal analysis revealed that the sedimentation coefficient of the HGPP was 2·6S in a 10 mM-imidazole-HCl buffer at pH 7·0 and 27 °C, but this component interacted with human κ-casein and formed a complex with s = 10·4S.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1987

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References

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