Hostname: page-component-77c89778f8-fv566 Total loading time: 0 Render date: 2024-07-18T19:50:07.638Z Has data issue: false hasContentIssue false

A modified form of lactoperoxidase isolated from milk cultures of streptococcus cremoris or Streptococcus lactis

Published online by Cambridge University Press:  01 June 2009

A. Pickering
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading
J. D. Oram
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading
B. Reiter
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading

Summary

Lactoperoxidase activity has been measured in whey form fresh milk and from milk cultured with Str. cremoris or Str. lactis. It was found that with benzidine as hydrogen donor, the optimum H2O2 concentration in whey from fresh milk was 10–4M, whereas in whey from cultured milk it was greater than 10–2M. The lactic acid streptococci appeared to modify lactoperoxidase. The modified form of the enzyme resembled lactoperoxidase in its absorption spectrum, its inhibition by fluoride and cyanide, its chromatographic behaviour on IRC50 resin and its activation energy of heat denaturation, but differed in its heat and pH stability, and its optimum hydrogen peroxide concentration for reaction with benzidine or o-dianisidine.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1962

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

Keilin, D. & Hartree, E. F. (1951). Biochem. J. 49, 88.CrossRefGoogle Scholar
Keilin, D. & Nicholls, P. (1958). Biochim. biophys. Acta, 29, 302.CrossRefGoogle Scholar
Kiermeier, F. & Kayser, C. (1960). Z. Lebensmitt Untersuch. 113, 203.CrossRefGoogle Scholar
Maehly, A. C. & Chance, B. (1954). In Glick, D., Methods of Biochemical Analysis, Vol. 1. New York: Interscience Publishers, Inc.CrossRefGoogle Scholar
Martin, A. P., Neufeld, H. A., Lucas, F. V. & Stotz, E. (1958). J. biol. Chem. 233, 206.CrossRefGoogle Scholar
Morrison, M., Hamilton, H. B. & Stotz, E. (1957). J. biol. Chem. 228, 767.CrossRefGoogle Scholar
Polis, B. D. & Shmukler, H. W. (1953). J. biol. Chem. 201, 475.CrossRefGoogle Scholar
Portmann, A. & Auclair, J. E. (1959). Lait, 39, 147.CrossRefGoogle Scholar
Woerner, F. (1961). Z. LebensmittUntersuch. 114, 106.Google Scholar
Wright, R. C. & Tramer, J. (1958). J. Dairy Res. 25, 104.CrossRefGoogle Scholar