Abstract
Various reagents which prevent enzyme inhibition by phenolic compounds were tested in attempts to improve the medium used to extract the Li-controlled enzyme activities from white clover leaves. The addition of 50 mm diethyldithiocarbamate to the extraction medium gave a fivefold increase in the enzyme activity of LiLi white clover extracts against p-nitrophenyl β-d-glucoside, linamarin-lotaustralin, and p-nitrophenyl β-d-galactoside. These three substrates were used in tests on the effect of genotype on enzyme activity. An absence of dominance at the Li locus was demonstrated, with a dosage effect of Li alleles on enzyme activity. A new Li allele was identified in the Lili clone, C11, which had low levels of enzyme activity. In crosses with two lili clones, Li(C11)li progeny were produced with activity levels similar to those of the C11 parent. Inhibition and heat-inactivation tests suggest that the lili clone, D4, produces an altered form of β-glucosidase which may also be present in LiLi plants. The nature of the Li locus is discussed.
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References
Anderson, J. W. (1968). Extraction of enzymes and subcellular organelles from plant tissues. Phytochemistry 71973.
Atwood, S. S. (1941). Controlled self- and cross-pollination of Trifolium repens. J. Am. Soc. Agron. 33538.
Butler, G. W., Bailey, R. W., and Kennedy, L. D. (1965). Studies on the glucosidase “linamarase.” Phytochemistry 4369.
Corkill, L. (1940). Cyanogenesis in white clover (Trifolium repens L.). I. Cyanogenesis in single plants. New Zeal. J. Sci. Tech. B2265.
Corkill, L. (1942). Cyanogenesis in white clover (Trifolium repens L.). V. The inheritance of cyanogenesis. New Zeal. J. Sci. Tech. B23178.
Dixon, M., and Webb, E. C. (1964). The Enzymes, 2nd ed., Longmans, London.
Duerksen, J. D., and Halvorson, H. O. (1958). Purification and properties of an inducible β-glucosidase of yeast. J. Biol. Chem. 2331113.
Haskins, F. A., and Gorz, H. J. (1965). Absence of dominance of the B gene in influencing β-glucosidase activity in Melilotus alba. Genetics 51733.
Hughes, M. A. (1968). Studies on the β-glucosidase system of Trifolium repens L. J. Exptl. Bot. 19427.
Loomis, W. D., and Battaile, J. (1966). Plant phenolic compounds and the isolation of plant enzymes. Phytochemistry 5423.
Maher, E. P. (1970). Studies on cyanogenesis in white clover. Ph.D. thesis, University of Newcastle upon Tyne.
Mehta, S. L., Srivastava, K. N., Mali, P. C., and Naik, M. S. (1972). Changes in the nucleic acid and protein fractions in opaque-2 maize kernels during development. Phytochemistry 11937.
Melville, J., Coop, I. E., Doak, B. W., and Reifer, I. (1940). Cyanogenesis in white clover (Trifolium repens L.). IV. Methods of determination. New Zealand J. Sci. Tech. B22144.
Morton, R. K. (1955). Methods of extraction of enzymes from animal tissues. In Colowick, S. P., and Kaplan, N. O. (eds.), Methods in Enzymology, Vol. 1, Academic Press, New York, p. 25.
Nelson, O. E., Jr. (1967). Biochemical genetics of higher plants. Ann. Rev. Genet. 1245.
Pirie, N. W. (1959). Leaf proteins. Ann. Rev. Plant Physiol. 1033.
Williams, W. (1954). An emasculation technique for certain species of Trifolium. Agron. J. 46182.
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Maher, E.P., Hughes, M.A. Studies on the nature of the Li locus in Trifolium repens L. II. The effect of genotype on enzyme activity and properties. Biochem Genet 8, 13–26 (1973). https://doi.org/10.1007/BF00485553
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DOI: https://doi.org/10.1007/BF00485553