Hostname: page-component-745bb68f8f-mzp66 Total loading time: 0 Render date: 2025-01-11T20:57:44.082Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of calcium on the stability of mares' milk lysozyme

Published online by Cambridge University Press:  01 June 2009

Richard L. J. Lyster
Richard L. J. Lyster
Affiliation:
Department of Food Science and Technology, Whiteknights, PO Box 226, University of Reading, Reading RG2 9AP, UK
Get access Rights & Permissions [Opens in a new window]

Summary

The three aspartic acid residues that form part of the Ca-binding site of mares' milk lysozyme have apparent pK values of 4·9, 4·3 and 4·1. The fluorescence of tryptophan has been used to compare the denaturation of mares' milk lysozyme by guanidinium chloride at various concentrations of Ca with that of hens' egg-white lysozyme (EC 3.2.1.17) and α-lactalbumin. Fluorescence revealed an intermediate stage in the denaturation of mares' milk lysozyme. The Ca-free form of mares' milk lysozyme is slightly more stable than that of α-lactalbumin, but its interaction with Ca is similar to that of α-lactalbumin, since only the native state binds Ca. Three-state models of denaturation can usefully be displayed on a ternary diagram.

Type
Original Articles
Information
Journal of Dairy Research , Volume 59 , Issue 3 , August 1992 , pp. 331 - 338
Copyright
Copyright © Proprietors of Journal of Dairy Research 1992

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

Acharya, K. R., Stuart, D. I., Walker, N. P. C., Lewis, M. & Phillips, D. C. 1989 Refined structure of baboon α-lactalbumin at 1–7 A resolution. Journal of Molecular Biology 208 99–127CrossRefGoogle ScholarPubMed
Buss, D. H. 1971 Isolation and partial characterization of lysozyme from baboon milk. Biochimica et Biophysica Acta 236 587–592CrossRefGoogle ScholarPubMed
Desmet, J., Hanssens, I. & Van Cauwelaert, F. 1987 Comparison of the binding of Na+ and Ca2+ to bovine α-lactalbumin. Biochimica et Biophysica Acta 912 211–219CrossRefGoogle ScholarPubMed
Desmet, J., Van Dael, H., Van Cauwelaert, F., Nitta, K. & Sugai, S. 1989 Comparison of the binding of Ca2+ and Mn2+ to bovine α-lactalbumin and equine lysozyme. Journal of Inorganic Biochemistry 37 185–191CrossRefGoogle ScholarPubMed
Ewbank, J. J. & Creighton, T. E. 1991 The molten globule protein conformation probed by disulphide bonds. Nature 350 518–520CrossRefGoogle ScholarPubMed
Haezbrouck, P., Morozova, L. & Van Cauwelaert, F. 1991 The thermal stability of equine and pigeon lysozymes. Journal of Inorganic Biochemistry 43 395CrossRefGoogle Scholar
Ikeguchi, M., Kuwajima, K., Mitani, M. & Sugai, S. 1986 a Evidence for identity between the equilibrium unfolding intermediate and a transient folding intermediate: a comparative study of the folding reactions of α-lactalbumin and lysozyme. Biochemistry 25 6965–6972CrossRefGoogle Scholar
Ikeguchi, M., Kuwajima, K. & Sugai, S. 1986 b Ca2+ -induced alteration in the unfolding behavior of α-lactalbumin. Journal of Biochemistry 99 1191–1201CrossRefGoogle ScholarPubMed
Kronman, M. J. 1989 Metal-ion binding and the molecular conformational properties of α-lactalbumin. Critical Reviews in Biochemistry and Molecular Biology 24 565–667CrossRefGoogle ScholarPubMed
McKenzie, H. A. & White, F. H. 1991 Lysozyme and α-lactalbumin: structure, function and interrelationships. Advances in Protein Chemistry 41 173–315CrossRefGoogle ScholarPubMed
Nitta, K., Tsuge, H., Shimazaki, K. & Sugai, S. 1988 Calcium-binding lysozymes. Biological Chemistry Hoppe-Seyler 369 671–675CrossRefGoogle ScholarPubMed
Nitta, K., Tsuge, H., Sugai, S. & Shimazaki, K. 1987 The calcium-binding property of equine lysozyme. FEBS Letters 223 405–408CrossRefGoogle ScholarPubMed
Nozaka, M., Kuwajima, K., Nitta, K. & Sugai, S. 1978 Detection and characterization of the intermediate on the folding pathway of human α-lactalbumin. Biochemistry 17 3753–3758CrossRefGoogle ScholarPubMed
Nozaki, Y. 1972 The preparation of guanidine hydrochloride. Methods in Enzymology 26 43–50CrossRefGoogle ScholarPubMed
Pfeil, W. & Privalov, P. L. 1976 Thermodynamic investigations of proteins. III. Thermodynamic description of lysozyme. Biophysical Chemistry 4 41–50CrossRefGoogle ScholarPubMed
Quarfoth, G. J. & Jenness, R. 1975 Isolation, composition and functional properties of α-lactalbumins from several species. Biochimica et Biophysica Acta 379 476–487CrossRefGoogle ScholarPubMed
Stuart, D. I., Acharya, K. R., Walker, N. P. C., Smith, S. G., Lewis, M. & Phillips, D. C. 1986 α Lactalbumin possesses a novel calcium binding loop. Nature 324 84–87CrossRefGoogle ScholarPubMed
Tsuge, H., Koseki, K., Miyano, M., Shimazaki, K., Chuman, T., Matsumoto, T., Noma, M., Nitta, K. & Sugai, S. 1991 A structural study of calcium-binding equine lysozyme by two-dimensional ′H-NMR. Biochimica et Biophysica Acta 1078 77–84CrossRefGoogle Scholar
Wetlaufer, D. B. 1962 Ultraviolet spectra of proteins and amino acids. Advances in Protein Chemistry 17 303–390CrossRefGoogle Scholar