title: Enzymic mechanism of starch breakdown in germinating rice seeds : 15. Immunochemical study on multiple forms of amylase.
abstract: The formation of multiple forms of amylases in germinating rice (Oryza sativa L. cv Kimmaze) grains was examined by means of isoelectric focusing, cross-immunoelectrophoresis, and rocket-line immunoelectrophoresis followed by a reaction of enzymic characterization by using beta-limit dextrin or starch as substrate. The constituents detected by isoelectric focusing were identified as three electrophoretically heterogeneous antigens. The major alpha-amylase bands A and B corresponded to a same antigen, the main portion of which was produced within 2 days' germination. The bulk of alpha-amylase D appeared between 2 and 4 days' germination. Component E, a debranching enzyme according to its action on the beta-limit dextrin, already exists in the ungerminated seeds; its amount decreases within the first 2 days of germination and increases again thereafter.Evidence showing that beta-amylase (band C) is produced by the scutellum at an early stage of germination was provided. The enzyme appeared in a suspension of the scutellum after a prolonged incubation.
authors: Research Institute for Biochemical Regulation, School of Agriculture, Nagoya University, Chikusa, Nagoya 464, Japan.
authors: J
authors: J
authors: Daussant
authors: S
authors: S
authors: Miyata
authors: T
authors: T
authors: Mitsui
authors: T
authors: T
authors: Akazawa