title: Pyrophosphate may be involved in regulation of bacterial glycogen synthesis.
abstract: Inorganic pyrophosphate is a potent inhibitor of the enzyme that catalyzes synthesis of the glucosyl donor for Escherichia coli glycogen synthesis, ADP-glucose pyrophosphorylase. The Ki is determined to be 40 microM and the substrate ATP, the activator, fructose 1,6-P2 or the allosteric inhibitor, AMP do not greatly affect the inhibition. PPi exhibits mixed type inhibition with the other substrate, glucose 1-P. The potential regulation of glycogen synthesis by PPi is discussed.
mesh_terms: D000245:Adenosine Diphosphate Glucose / Q000096:biosynthesis; D002250:Carbon Radioisotopes; D011756:Diphosphates / Q000494:pharmacology; D004926:Escherichia coli / Q000201:enzymology*; D051599:Glucose-1-Phosphate Adenylyltransferase; D005958:Glucosephosphates / Q000378:metabolism; D006003:Glycogen / Q000096:biosynthesis*; D007700:Kinetics; D009713:Nucleotidyltransferases / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; D011756:Diphosphates; D005958:Glucosephosphates; D000245:Adenosine Diphosphate Glucose; D006003:Glycogen; C031590:glucose-1-phosphate; D009713:Nucleotidyltransferases; D051599:Glucose-1-Phosphate Adenylyltransferase