title: Purification and characterization of adenosine diphosphate glucose pyrophosphorylase from maize/potato mosaics.
abstract: Adenosine diphosphate glucose pyrophosphorylase (AGPase) catalyzes a rate-limiting step in starch biosynthesis. The reaction produces ADP-glucose and pyrophosphate from glucose-1-P and ATP. Investigations from a number of laboratories have shown that alterations in allosteric properties as well as heat stability of this enzyme have dramatic positive effects on starch synthesis in the potato (Solanum tuberosum) tuber and seeds of important cereals. Here, we report the characterization of purified recombinant mosaic AGPases derived from protein motifs normally expressed in the maize (Zea mays) endosperm and the potato tuber. These exhibit properties that should be advantageous when expressed in plants. We also present an in-depth characterization of the kinetic and allosteric properties of these purified recombinant AGPases. These data point to previously unrecognized roles for known allosteric effectors.
authors.affiliation: Department of Biochemistry and Molecular Biology , University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Susan K
authors.initials: SK
authors.lastname: Boehlein
authors.forename: Aileen K
authors.initials: AK
authors.lastname: Sewell
authors.forename: Joanna
authors.initials: J
authors.lastname: Cross
authors.forename: Jon D
authors.initials: JD
authors.lastname: Stewart
authors.forename: L Curtis
authors.initials: LC
authors.lastname: Hannah
mesh_terms: D000595:Amino Acid Sequence; D016384:Consensus Sequence; D051599:Glucose-1-Phosphate Adenylyltransferase; D008969:Molecular Sequence Data; D009030:Mosaicism; D009713:Nucleotidyltransferases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010957:Plasmids; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D011198:Solanum tuberosum / Q000201:enzymology* / Q000235:genetics; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics
chemical_list: D021122:Protein Subunits; D011994:Recombinant Proteins; D009713:Nucleotidyltransferases; D051599:Glucose-1-Phosphate Adenylyltransferase