Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-12-02T20:41:42.978Z Has data issue: false hasContentIssue false

The action of rennets on the caseins: I. Rennin action on β-casein-B in solution

Published online by Cambridge University Press:  01 June 2009

L. K. Creamer
Affiliation:
New Zealand Dairy Research Institute, Palmerston North, New Zealand
O. E. Mills
Affiliation:
New Zealand Dairy Research Institute, Palmerston North, New Zealand
E. L. Richards
Affiliation:
Department of Chemistry and Biochemistry, Massey University, Palmerston North, New Zealand

Summary

A study of the hydrolysis of β-casein-B by crystalline rennin or rennet extract at pH 6·5, using a disk electrophoresis technique, showed that 3 bonds in β-casein are appreciably more sensitive than the others to rennin proteolysis, and that these bonds are probably located near the C-terminus of the protein. The most susceptible bond is hydrolysed, at 10°C, about 200 times faster than any other bond, whilst at 37°C it is hydrolysed 60 times faster. A study of the hydrolysis of this bond showed that its rate of hydrolysis at 37°C and pH 6·5 is decreased by either increased ionic strength or increased calcium ion concentration at constant ionic strength. Conformational changes in the substrate are probably responsible for these effects.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1971

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

Bakri, M. B. A. (1968). Thesis, Washington State University.Google Scholar
Bernhard, S. A. & Gutfreund, H. (1970). Phil. Trans. R. Soc. B., 257, 105.Google Scholar
Davis, B. J. (1964). Ann. N.Y. Acad. Sci. 121, 404.CrossRefGoogle Scholar
Fox, P. F. (1969 a). J. Dairy Sci. 52, 1214.CrossRefGoogle Scholar
Fox, P. F. (1969 b). J. Dairy Res. 36, 427.CrossRefGoogle Scholar
Garnier, J. (1966). J. molec. Biol. 19, 586.CrossRefGoogle Scholar
Herskovits, T. T. (1966). Biochemistry, Easton 5, 1018.CrossRefGoogle Scholar
Lawrence, R. C. & Creamer, L. K. (1969). J. Dairy Res. 36, 11.CrossRefGoogle Scholar
Ledford, R. A., Chen, J. H. & Nath, K. R. (1968). J. Dairy Sci. 51, 792.CrossRefGoogle Scholar
Ledford, R. A., O'sullivan, A. C. & Nath, K. R. (1966). J. Dairy Sci. 49, 1098.CrossRefGoogle Scholar
Lindqvist, B. (1963). Dairy Sci. Abstr. 25, 257, 299.Google Scholar
Lindqvist, B. & Storgårds, T. (1960). Acta chem. scand. 14, 757.CrossRefGoogle Scholar
Manson, W. & Annan, W. D. (1970). 18th Int. Dairy Congr., Sydney 1E, 33.Google Scholar
Mickelsen, R. & Fish, N. L. (1970). J. Dairy Sci. 53, 704.CrossRefGoogle Scholar
Mills, O. E. (1970). Thesis, Massey University.Google Scholar
Noelken, M. & Reibstein, M. (1968). Archs Biochem. Biophys. 123, 397.CrossRefGoogle Scholar
Ornstein, L. (1964). Ann. N.Y. Acad. Sci. 121, 321.CrossRefGoogle Scholar
Peterson, R. F. & Kopfler, F. C. (1966). Biochem. biophys. Res. Commun. 22, 388.CrossRefGoogle Scholar
Peterson, R. F., Nauman, L. W. & Mcmeekin, T. L. (1958). J. Am. chem. Soc. 80, 95.CrossRefGoogle Scholar