Summary
Changes in amylase isozyme patterns on polyacrylamide gels were followed during maturation in grains of Deba Abed barley. Early stage seeds contained a single, high-mobility enzyme (Band A) which had an estimated molecular weight of 4.2×104 and a high activity with β-limit dextrin as a substrate. It was shown, by dissection, that Band A was confined to the aleurone layer and probably represented the initial product of amylase synthesis.
This form was succeeded, in mid-course, by a less mobile form (Band B), a β-amylase with a molecular weight of approximately 1.3×105. Late-dough stage grains contained a complex of low-mobility β-amylase bands which were shown, by papain digestion, to be protein-bound forms of Band B.
The changes are discussed on the basis of a unified series consisting of elaborated forms of the initial Band A type of activity.
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References
Andrews, P.: Estimation of the molecular weights of proteins by sephadex gel filtration. Biochem. J. 91, 222–233 (1964).
Bernfeld, P.: Amylases α and β. Methods in enzymology, vol. 1 p. 149–158. New York: Academic Press 1955.
Coddington, A., Fincham, J. R. S., Sundaram, T. K.: Multiple active varieties of Neurospora glutamate dehydrogenase formed by hybridisation between two inactive mutant proteins in vivo and in vitro. J. molec. Biol. 17, 503–512 (1966).
Duffus, C. M.: α-amylase activity in the developing barley grain and its dependence upon gibberellic acid. Phytochem. 8, 1205–1209 (1969).
Engel, C.: The distribution of amylase, proteinase and esterase in resting cereals. Rec. Trav. chim. Pays-Bas 64, 318–320 (1945).
Englard, S., Singer, T. P.: Physicochemical studies on β-amylase. J. biol. Chem. 187, 213–220 (1950).
Evers, A. D.: Development of the endosperm of wheat. Ann. Bot., N.S. 34, 547–555 (1970).
Jacobsen, J. V., Scandalios, J. G., Varner, J. E.: Multiple forms of amylase induced by gibberellic acid in isolated barley aleurone layers. Plant Physiol. 45, 367–371 (1970).
Lowry, O. H., Rosebrough, N. J., Lewis-Farr, A., Randall, R. J.: Protein measurement with the folin phenol reagent. J. biol. Chem. 193, 265–275 (1951).
May, L. H., Buttrose, M. S.: Physiology of cereal grain. II. Starch granule formation in the developing barley kernel. Aust. J. biol. Sci. 12, 146–159 (1959).
Olered, R.: Development of α-amylase and falling number in wheat and rye during ripening. Thesis No 23. Agric. Coll. of Sweden, Uppsala. 1–101 (1967).
Paleg, L. G.: Physiological effects of gibberellic acid. 2. On starch hydrolysing enzymes of barley endosperm. Plant Physiol. 35, 902–906 (1960).
Price, G. M.: An apparatus for the electrophoresis of proteins on polyacrylamide gel. Lab. Pract. 17, 467–470 (1968).
Rowsell, E. V., Goad, L. J.: The constituent of wheat binding latent β-amylase. Biochem. J. 84, 73 P (1962).
Schwimmer, S., Balls, A. K.: Isolation and properties of crystalline α-amylase from germinated barley. J. biol. Chem. 179, 1063–1074 (1949).
Varner, J. E.: Gibberellic acid controlled synthesis of α-amylase in barley endosperm. Plant. Physiol. 39, 413–415 (1964).
Whelan, W. J.: Formation, mobilisation and transformation of carbohydrates. Starch and similar polysaccharides. Encyclop. of Plant Physiol., vol. VI, p. 154–240. Berlin-Göttingen-Heidelberg: Springer 1958.
Yomo, J.: Studies on the α-amylase activating substance. IV. On the amylase activating action of gibberellin. Hakko Kyokaishi. 18, 600–602 (1960).
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Stoddart, J.L. Sequential changes in amylase isozymes during grain maturation in barley. Planta 97, 70–82 (1971). https://doi.org/10.1007/BF00388407
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DOI: https://doi.org/10.1007/BF00388407