Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-26T12:33:39.848Z Has data issue: false hasContentIssue false

A preliminary study by gel filtration and ultracentrifugation of the interaction of bovine milk caseins with detergents

Published online by Cambridge University Press:  01 June 2009

G. C. Cheeseman
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading

Summary

The detergents sodium dodecyl sulphate and octyl phenoxy polyethoxyethanol interact with casein and cause dissociation of the high-molecular-weight casein aggregates. It is presumed that the detergent binds with hydrophobic regions in the casein molecule. The size of the complexes formed between detergents and αs1-casein, β-casein and κ-casein, as estimated by gel filtration and sedimentation velocity experiments, suggests that the caseins were complexed as monomers.

During gel filtration under non-reducing conditions, detergent-κ-casein complexes were separated from other major components because of their conversion through formation of disulphide bonds into high-molecular-weight aggregates. This reaction, which did not occur in sedimentation velocity experiments, was presumably facilitated by the changes in the equilibrium between the individual caseins during gel filtration.

Sedimentation velocity experiments showed that a ratio of about 40 detergent molecules to 1 casein molecule was required to give the smallest casein-detergent complex.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1968

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Anacker, E. W., Rush, R. M. & Johnson, J. S. (1964). J. phys. Chem. 68, 81.CrossRefGoogle Scholar
Nakai, S., Wilson, H. K. & Herreid, E. O. (1966). J. Dairy Sci. 49, 1331.CrossRefGoogle Scholar
Payens, T. A. J. & Schmidt, D. G. (1965). Biochim. biophys. Acta 109, 492.Google Scholar
Yaguchi, M., Davies, D. T. & Kim, Y. K. (1968). J. Dairy Sci. 51, 4.CrossRefGoogle Scholar
Yaguchi, M. & Tarassuk, N. P. (1967). J. Dairy Sci. 50, 1985.CrossRefGoogle Scholar
Zittle, C. A. & Custer, J. H. (1963). J. Dairy Sci. 46, 1183.CrossRefGoogle Scholar