Biochemical Genetics

, Volume 13, Issue 9–10, pp 733–742 | Cite as

Molecular nature of β-Galactosidase from different tissues in two strains of the house mouse

  • Reza Seyedyazdani
  • Ylva Floderus
  • Lars-G. Lundin


One inbred mouse strain, C57BL/Kl, has high galactosidase activities in all tissues, while another strain, DBA/2/Kl, has low activities determined by the Bgs locus. β-Galactosidase from these two strains was partly purified by a five-step procedure: acidification, ammonium sulfate precipitation, gel filtration at two pHs, and isoelectric focusing. No qualitative differences were found between the enzyme preparations from the two strains. They had identical heat inactivation curves, pH optima, molecular weights, and isoelectric points, and the Km values were very similar. It thus seems that this genetic difference in enzyme activity probably cannot be explained by a variation of the galactosidase-specific activity but rather reflects a difference in number of enzyme molecules. Eight different isoenzymes were separated from liver, kidney, and spleen. Each isoenzyme has a different electrophoretic mobility and there is a stepwise increase in molecular weight from 143,000 to 380,000 beginning with the protein having the lowest isoelectric point. A likely interpretation is that the isoenzymes bind a smaller polypeptide in varying numbers in addition to the enzymatic polypeptide per se.

Key words

β-galactosidase house mouse isoenzymes genetic variation molecular properties tissue differences 


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  1. Felton, J., Meisler, M., and Paigen, K. (1974). A locus determining β-galactosidase activity in the mouse. J. Biol. Chem. 2493267.Google Scholar
  2. Ganschow, R., and Schimke, R. T. (1968). Genetic control of catalase in inbred mice. In San Pietro, A., Lamborg, M. R., and Kenney, F. T. (eds.), Regulatory Mechanisms for Protein Synthesis in Mammalian Cells, Academic Press, New York, p. 377.Google Scholar
  3. Ganschow, R., and Schimke, R. T. (1969). Independent genetic control of the catalytic activity and the rate of degradation of catalase in mice. J. Biol. Chem. 2444649.Google Scholar
  4. Kint, J. A., Dacremont, G., Carton, D., Orye, E., and Hooft, C. (1973). Mucopolysaccharidosis: Secondarily induced abnormal distribution of lysosomal isoenzymes. Science 181352.Google Scholar
  5. Lowry, O. H., Rosenbrough, N. J., Farr, A. L., and Randall, R. J. (1951). Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193265.Google Scholar
  6. Lundin, L.-G. (1970). Genetical Variation of Hydrolases in the Mouse, Institute for Medical Genetics of the University of Uppsala, Uppsala, Sweden.Google Scholar
  7. Lundin, L.-G., and Seyedyazdani, R. (1973) Mendelian inheritance of variations in β-galactosidase activities in the house mouse. Biochem. Genet 10351.Google Scholar
  8. Paigen, K., and Felton, J. (1971). Genetic factors affecting enzyme activity. In Mitrich, E. (ed.), Regulation of Cell Metabolism: Organizational and Pharmacological Aspects on the Molecular Level, Academic Press, New York, p. 185.Google Scholar
  9. Rechcigl, M., Jr., and Heston, W. E. (1967). Genetic regulation of enzyme activity in mammalian system by the alteration of the rate of enzyme degradation. Biochem. Biophys. Res. Commun. 27119.Google Scholar
  10. Reisfeld, R. A., Lewis, U. J., and Williams, D. E. (1962). Disc electrophoresis of basic proteins and peptides on polyacrylamide gels. Nature 195281.Google Scholar
  11. Seyedyazdani, R., and Lundin, L.-G. (1973). Association between β-galactosidase activities and coat color in mice. J. Hered. 64295.Google Scholar
  12. Swank, R. T., and Paigen, K. (1973). Biochemical and genetic evidence for a macromolecular β-glucuronidase complex in microsomal membranes. J. Mol. Biol. 77371.Google Scholar

Copyright information

© Plenum Publishing Corporation 1975

Authors and Affiliations

  • Reza Seyedyazdani
    • 1
  • Ylva Floderus
    • 1
  • Lars-G. Lundin
    • 1
  1. 1.The Institute for Medical GeneticsUppsalaSweden

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