title: Binding of sugar phosphates, inositol phosphates and phosphorylated amino acids to actin.
abstract: Binding of biological phosphate compounds to actin was investigated by the effect of these compounds on the critical concentration of the pointed ends of gelsolin-capped actin filaments. According to this assay millimolar concentrations of glucose 6-phosphate and the bisphosphorylated sugars fructose 1,6-bisphosphate, fructose 2,6-bisphosphate, glucose 1,6-bisphosphate, sedoheptulose 1,7-bisphosphate and 2,3-bisphosphoglycerate were found to associate with actin. Glycerophosphoinositol phosphates bound to actin if they were present in millimolar concentrations, and if carbon atom 4 of the inositol ring was phosphorylated and carbon atom 5 was free of phosphate. Also phosphoserine and phosphotyrosine were found to interact with actin. Most of the actin-binding compounds stabilized actin filaments by decreasing the critical concentration suggesting that these compounds had a higher affinity for the subunits along actin filaments than for actin monomers. However, 2,3-bisphosphoglycerate and fructose 2,6-bisphosphate increased the critical concentration probably because these sugar phosphates bound to actin monomers thereby inhibiting actin polymerization.
authors.affiliation: Institute of Physiological Chemistry, Ruhr-University Bochum, Federal Republic of Germany.
authors.forename: A
authors.initials: A
authors.lastname: Gaertner
authors.forename: G W
authors.initials: GW
authors.lastname: Mayr
authors.forename: A
authors.initials: A
authors.lastname: Wegner
mesh_terms: D000199:Actins / Q000378:metabolism*; D000596:Amino Acids / Q000378:metabolism*; D001665:Binding Sites; D002135:Calcium-Binding Proteins; D005454:Fluorescence Polarization; D018260:Gelsolin; D007295:Inositol Phosphates / Q000378:metabolism*; D008840:Microfilament Proteins; D010766:Phosphorylation; D013403:Sugar Phosphates / Q000378:metabolism*
chemical_list: D000199:Actins; D000596:Amino Acids; D002135:Calcium-Binding Proteins; D018260:Gelsolin; D007295:Inositol Phosphates; D008840:Microfilament Proteins; D013403:Sugar Phosphates