title: Isolation and Characterization of the Amyloplast Envelope-Membrane from Cultured White-Wild Cells of Sycamore (Acer pseudoplatanus L.).
abstract: To study the characteristic features of the amyloplast, a uniquely differentiated plastid-type which synthesizes and accumulates reserve starch, in comparison with those of the chloroplast, these two types of plastids were isolated from white-wild and green-mutant protoplasts of cultured sycamore (Acer pseudoplatanus L.) cells, respectively. The intactness of the isolated amyloplast preparations was 70%. Electron microscopic ultrastructural analysis of both plastid types revealed unique structural features of the green-mutant chloroplasts, including well developed grana membranes and abundant ribosomal particles and plastoglobuli. After osmotic rupture of the isolated amyloplasts and chloroplasts, a clear separation of the envelope-membranes was achieved by discontinuous sucrose density gradient centrifugation. Although the visible absorption spectra of the envelope lipid components were indistinguishable between the amyloplasts and chloroplasts, the envelope-membrane polypeptide patterns were clearly distinct as judged by denaturing electrophoresis. By immunoblotting analysis using the specific antiserum raised against the pea chloroplast 29-kilodalton Pi-translocator, the amount of this carrier-protein (31-kilodalton) in the white-wild amyloplast envelope-membranes was estimated to be at least 10-fold less than in the green-mutant envelopes.
authors: Research Institute for Biochemical Regulation, School of Agriculture, Nagoya University, Chikusa, Nagoya 464, Japan.
authors: J
authors: J
authors: Ngernprasirtsiri
authors: P
authors: P
authors: Harinasut
authors: D
authors: D
authors: Macherel
authors: K
authors: K
authors: Strzalka
authors: T
authors: T
authors: Takabe
authors: T
authors: T
authors: Akazawa
authors: K
authors: K
authors: Kojima